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Perera GS, Rahman MA, Blazevski A, Wood A, Walia S, Bhaskaran M, Sriram S. Rapid Conductometric Detection of SARS-CoV-2 Proteins and Its Variants Using Molecularly Imprinted Polymer Nanoparticles. Adv Mater Technol 2022; 8:2200965. [PMID: 36718387 PMCID: PMC9877662 DOI: 10.1002/admt.202200965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 08/20/2022] [Indexed: 06/18/2023]
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) biosensors have captured more attention than the conventional methodologies for SARS-CoV-2 detection due to having cost-effective platforms and fast detection. However, these reported SARS-CoV-2 biosensors suffer from drawbacks including issues in detection sensitivity, degradation of biomaterials on the sensor's surface, and incapability to reuse the biosensors. To overcome these shortcomings, molecularly imprinted polymer nanoparticles (nanoMIPs) incorporated conductometric biosensor for highly accurate, rapid, and selective detection of two model SARS-CoV-2 proteins: (i) receptor binding domain (RBD) of the spike (S) glycoprotein and (ii) full length trimeric spike protein are introduced. In addition, these biosensors successfully responded to several other SARS-CoV-2 RBD spike protein variants including Alpha, Beta, Gamma, and Delta. Our conductometric biosensor selectively detects the two model proteins and SARS-CoV-2 RBD spike protein variant samples in real-time with sensitivity to a detection limit of 7 pg mL-1 within 10 min of sample incubation. A battery-free, wireless near-field communication (NFC) interface is incorporated with the biosensor for fast and contactless detection of SARS-CoV-2 variants. The smartphone enabled real-time detection and on-screen rapid result for SARS-CoV-2 variants can curve the outbreak due to its ability to alert the user to infection in real time.
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Affiliation(s)
- Ganganath S. Perera
- Functional Materials and Microsystems Research Group and the Micro Nano Research FacilityRMIT UniversityMelbourneVIC3001Australia
| | - Md. Ataur Rahman
- Functional Materials and Microsystems Research Group and the Micro Nano Research FacilityRMIT UniversityMelbourneVIC3001Australia
| | - April Blazevski
- Functional Materials and Microsystems Research Group and the Micro Nano Research FacilityRMIT UniversityMelbourneVIC3001Australia
| | | | - Sumeet Walia
- Functional Materials and Microsystems Research Group and the Micro Nano Research FacilityRMIT UniversityMelbourneVIC3001Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and the Micro Nano Research FacilityRMIT UniversityMelbourneVIC3001Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and the Micro Nano Research FacilityRMIT UniversityMelbourneVIC3001Australia
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Nirantar S, Patil B, Tripathi DC, Sethu N, Narayanan RV, Tian J, Bhaskaran M, Walia S, Sriram S. Metal-Air Field Emission Devices - Nano Electrode Geometries Comparison of Performance and Stability. Small 2022; 18:e2203234. [PMID: 36094789 DOI: 10.1002/smll.202203234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 07/31/2022] [Indexed: 06/15/2023]
Abstract
Air-channel devices have a special advantage due to the promise of vacuum-like ballistic transport in air, radiation insensitivity, and nanoscale size. Here, achieving high current at low voltage along with considerable mechanical stability is a primary issue. The comparative analysis of four planar and metallic electrode-pair geometries at 10 nm channel length is presented. The impact of nano-electrode-pair geometries on overall device performance is investigated. Air-channel devices are operated at the ultra-low voltage of 5 mV to demonstrate the device dynamics of air-channel devices at low power. Investigations focus on the direct tunneling (DT) mechanism which is dominant in the low-voltage regime. Comparative analysis of different electrode-pair geometries reveals two orders of magnitude increment in the current just by modulating the electrode-pair structure. Theoretical analysis suggests that the emission current is directly related to the active junction area within the metal-air-metal interface at the direct tunneling regime. The geometry-dependent mechanical stability of different electrode pairs is compared by imaging biasing triggered nanoscale structural changes and pulsed biasing stress analysis. The results and claims are confirmed and consolidated with the statistical analysis. Experimental investigations provide strong directions for high-performance and stable devices. In-depth theoretical discussions will enable the accurate modeling of emerging low-power, high-speed, radiation-hardened nanoscale vacuum electronics.
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Affiliation(s)
- Shruti Nirantar
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
- School of Engineering, RMIT University, GPO Box 2476, Melbourne, Victoria, 3001, Australia
| | - Basanagounda Patil
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
| | - Durgesh C Tripathi
- Faculty of Electrical Engineering, Technion - Israel Institute of Technology, Haifa, 3200003, Israel
| | - Nilamani Sethu
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
- School of Engineering, RMIT University, GPO Box 2476, Melbourne, Victoria, 3001, Australia
| | - Ramakrishnan V Narayanan
- Department of Micro and Nanoelectronics, Vellore Institute of Technology, Vellore, Tamil Nadu, 632014, India
| | - Jie Tian
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
- School of Engineering, RMIT University, GPO Box 2476, Melbourne, Victoria, 3001, Australia
| | - Sumeet Walia
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
- School of Engineering, RMIT University, GPO Box 2476, Melbourne, Victoria, 3001, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
- School of Engineering, RMIT University, GPO Box 2476, Melbourne, Victoria, 3001, Australia
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MATUROSTRAKUL B, Bhaskaran M, Jang H, Nair V, Nair G, Abate M, Teperman L, Grodstein E. POS-781 THROMBOTIC MICROANGIOPATHY IN RENAL TRANSPLANT RECIPIENT WITH NPHS 2 GENE MUTATION. Kidney Int Rep 2022. [DOI: 10.1016/j.ekir.2022.01.817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Rahman MA, Cai L, Tawfik SA, Tucker S, Burton A, Perera G, Spencer MJS, Walia S, Sriram S, Gutruf P, Bhaskaran M. Nicotine Sensors for Wearable Battery-Free Monitoring of Vaping. ACS Sens 2022; 7:82-88. [PMID: 34877860 DOI: 10.1021/acssensors.1c01633] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Nicotine, an addictive substance in tobacco products and electronic cigarettes (e-cigs), is recognized for increasing the risk of cardiovascular and respiratory disorders. Careful real-time monitoring of nicotine exposure is critical in alleviating the potential health impacts of not just smokers but also those exposed to second-hand and third-hand smoke. Monitoring of nicotine requires suitable sensing material to detect nicotine selectively and testing under free-living conditions in the standard environment. Here, we experimentally demonstrate a vanadium dioxide (VO2)-based nicotine sensor and explain its conductometric mechanisms with compositional analysis and density functional theory (DFT) calculations. For real-time monitoring of nicotine vapor from e-cigarettes in the air, the sensor is integrated with an epidermal near-field communication (NFC) interface that enables battery-free operation and data transmission to smart electronic devices to record and store sensor data. Collectively, the technique of sensor development and integration expands the use of wearable electronics for real-time monitoring of hazardous elements in the environment and biosignals wirelessly.
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Affiliation(s)
- Md. Ataur Rahman
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria 3001, Australia
| | - Le Cai
- Department of Biomedical Engineering, University of Arizona, Tucson, Arizona 85721, United States
| | - Sherif Abdulkader Tawfik
- ARC Centre of Excellence in Exciton Science, School of Science, RMIT University, Melbourne, Victoria 3001, Australia
- Institute for Frontier Materials, Deakin University, Geelong, Victoria 3216, Australia
| | - Stuart Tucker
- Department of Biomedical Engineering, University of Arizona, Tucson, Arizona 85721, United States
| | - Alex Burton
- Department of Biomedical Engineering, University of Arizona, Tucson, Arizona 85721, United States
| | - Ganganath Perera
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria 3001, Australia
| | | | - Sumeet Walia
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria 3001, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria 3001, Australia
| | - Philipp Gutruf
- Department of Biomedical Engineering, BIO5 Institute, Department of Electrical Engineering, University of Arizona, Tucson, Arizona 85721, United States
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria 3001, Australia
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You X, Ako RT, Lee WSL, Bhaskaran M, Sriram S, Fumeaux C, Withayachumnankul W. Terahertz transmissive half-wave metasurface with enhanced bandwidth: publisher's note. Opt Lett 2021; 46:4640. [PMID: 34525069 DOI: 10.1364/ol.441390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Indexed: 06/13/2023]
Abstract
This publisher's note contains corrections to Opt. Lett.46, 4164 (2021)OPLEDP0146-959210.1364/OL.431285.
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You X, Ako RT, Lee WSL, Bhaskaran M, Sriram S, Fumeaux C, Withayachumnankul W. Terahertz transmissive half-wave metasurface with enhanced bandwidth. Opt Lett 2021; 46:4164-4167. [PMID: 34469965 DOI: 10.1364/ol.431285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 07/13/2021] [Indexed: 06/13/2023]
Abstract
Polarization conversion is useful for studies of chiral structures in biology and chemistry, and for polarization diversity in communications. It is conventionally realized with wave plates, which, however, present challenges due to limited material availability, as well as narrow bandwidth and low efficiency at terahertz frequencies. To enhance bandwidth and efficiency, the concept of the Huygens' metasurface is adopted here for a transmissive half-wave plate. The half-wave metasurface is designed following the optimal frequency-independent circuit parameters provided by a broadband semi-analytical approach. Simulation results of an optimal design suggest that a 15-dB extinction ratio can be sustained from 219 GHz to 334 GHz, corresponding to a fractional bandwidth of 41.6%. The measured results indicate that the fabricated structure enables a 15-dB extinction ratio from 220 GHz to 303 GHz, with a cross-polarization transmission efficiency above 76.7% for both linear and circular polarizations. This half-wave metasurface design can be readily integrated into compact terahertz systems for diverse applications.
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Kayani ABA, Kuriakose S, Monshipouri M, Khalid FA, Walia S, Sriram S, Bhaskaran M. UV Photochromism in Transition Metal Oxides and Hybrid Materials. Small 2021; 17:e2100621. [PMID: 34105241 DOI: 10.1002/smll.202100621] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 03/11/2021] [Indexed: 06/12/2023]
Abstract
Limited levels of UV exposure can be beneficial to the human body. However, the UV radiation present in the atmosphere can be damaging if levels of exposure exceed safe limits which depend on the individual the skin color. Hence, UV photochromic materials that respond to UV light by changing their color are powerful tools to sense radiation safety limits. Photochromic materials comprise either organic materials, inorganic transition metal oxides, or a hybrid combination of both. The photochromic behavior largely relies on charge transfer mechanisms and electronic band structures. These factors can be influenced by the structure and morphology, fabrication, composition, hybridization, and preparation of the photochromic materials, among others. Significant challenges are involved in realizing rapid photochromic change, which is repeatable, reversible with low fatigue, and behaving according to the desired application requirements. These challenges also relate to finding the right synergy between the photochromic materials used, the environment it is being used for, and the objectives that need to be achieved. In this review, the principles and applications of photochromic processes for transition metal oxides and hybrid materials, photocatalytic applications, and the outlook in the context of commercialized sensors in this field are presented.
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Affiliation(s)
- Aminuddin Bin Ahmad Kayani
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Australia
| | - Sruthi Kuriakose
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Australia
| | - Mahta Monshipouri
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Australia
| | | | - Sumeet Walia
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Australia
- School of Engineering, RMIT University, Melbourne, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Australia
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Tan TC, Srivastava YK, Ako RT, Wang W, Bhaskaran M, Sriram S, Al-Naib I, Plum E, Singh R. Active Control of Nanodielectric-Induced THz Quasi-BIC in Flexible Metasurfaces: A Platform for Modulation and Sensing. Adv Mater 2021; 33:e2100836. [PMID: 34050568 DOI: 10.1002/adma.202100836] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 04/02/2021] [Indexed: 06/12/2023]
Abstract
A bound state in the continuum (BIC) is a nonradiating state of light embedded in the continuum of propagating modes providing drastic enhancement of the electromagnetic field and its localization at micro-nanoscale. However, access to such modes in the far-field requires symmetry breaking. Here, it is demonstrated that a nanometric dielectric or semiconductor layer, 1000 times thinner than the resonant wavelength (λ/1000), induces a dynamically controllable quasi-bound state in the continuum (QBIC) with ultrahigh quality factor in a symmetric metallic metasurface at terahertz frequencies. Photoexcitation of nanostrips of germanium activates ultrafast switching of a QBIC resonance with 200% transmission intensity modulation and complete recovery within 7 ps on a low-loss flexible substrate. The nanostrips also form microchannels that provide an opportunity for BIC-based refractive index sensing. An optimization model is presented for (switchable) QBIC resonances of metamaterial arrays of planar symmetric resonators modified with any (active) dielectric for inverse metamaterial design that can serve as an enabling platform for active micro-nanophotonic devices.
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Affiliation(s)
- Thomas CaiWei Tan
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
- Centre for Disruptive Photonic Technologies, The Photonics Institute, Nanyang Technological University, Singapore, 637371, Singapore
| | - Yogesh Kumar Srivastava
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
- Centre for Disruptive Photonic Technologies, The Photonics Institute, Nanyang Technological University, Singapore, 637371, Singapore
| | - Rajour Tanyi Ako
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC 3000, Australia
| | - Wenhao Wang
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
- Centre for Disruptive Photonic Technologies, The Photonics Institute, Nanyang Technological University, Singapore, 637371, Singapore
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC 3000, Australia
- ARC Centre of Excellence for Transformative Meta-Optical Systems, RMIT University, Melbourne, VIC 3000, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC 3000, Australia
- ARC Centre of Excellence for Transformative Meta-Optical Systems, RMIT University, Melbourne, VIC 3000, Australia
| | - Ibraheem Al-Naib
- Biomedical Engineering Department, College of Engineering, Imam Abdulrahman Bin Faisal University, Dammam, 34212, Saudi Arabia
| | - Eric Plum
- Centre for Photonic Metamaterials & Optoelectronics Research Centre, Zepler Institute, University of Southampton, Southampton, SO17 1BJ, UK
| | - Ranjan Singh
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
- Centre for Disruptive Photonic Technologies, The Photonics Institute, Nanyang Technological University, Singapore, 637371, Singapore
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Heda R, Yazawa M, Shi M, Bhaskaran M, Aloor FZ, Thuluvath PJ, Satapathy SK. Non-alcoholic fatty liver and chronic kidney disease: Retrospect, introspect, and prospect. World J Gastroenterol 2021; 27:1864-1882. [PMID: 34007127 PMCID: PMC8108029 DOI: 10.3748/wjg.v27.i17.1864] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 03/07/2021] [Accepted: 04/07/2021] [Indexed: 02/06/2023] Open
Abstract
With the growing prevalence of obesity and diabetes in the United States and across the world, a rise in the overall incidence and prevalence of non-alcoholic fatty liver disease (NAFLD) is expected. The risk factors for NAFLD are also associated with the development of chronic kidney disease (CKD). We review the epidemiology, risk factors, genetics, implications of gut dysbiosis, and specific pathogenic mechanisms linking NAFLD to CKD. Mechanisms such as ectopic lipid accumulation, cellular signaling abnormalities, and the interplay between fructose consumption and uric acid accumulation have led to the emergence of potential therapeutic implications for this patient population. Transplant evaluation in the setting of both NAFLD and CKD is also reviewed. Potential strategies for surveillance and management include the monitoring of comorbidities, the use of non-invasive fibrosis scoring systems, and the measurement of laboratory markers. Lastly, we discuss the management of patients with NAFLD and CKD, from preventative measures to experimental interventions.
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Affiliation(s)
- Rajiv Heda
- Department of Internal Medicine, Tulane University School of Medicine, New Orleans, LA 70112, United States
| | - Masahiko Yazawa
- Department of Nephrology and Hypertension, St. Marianna University School of Medicine, Kawasaki 216-8511, Japan
| | - Michelle Shi
- Department of Internal Medicine, Donald and Barbara Zucker School of Medicine, Northwell Health, Manhasset, NY 11030, United States
| | - Madhu Bhaskaran
- Department of Nephrology, Northwell Health/Zucker School of Medicine at Hosftra, Manhasset, NY 11030, United States
| | - Fuad Zain Aloor
- Department of Internal Medicine, Baylor College of Medicine, Houston, TX 77030, United States
| | - Paul J Thuluvath
- Institute of Digestive Health & Liver Diseases, Mercy Medical Center, Baltimore, MD 21202, United States
| | - Sanjaya K Satapathy
- Department of Internal Medicine, Donald and Barbara Zucker School of Medicine, Northwell Health, Manhasset, NY 11030, United States
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Adnani H, Khatri A, Agrawal N, Molmenti E, Bhaskaran M. COVID-19 in an Asymptomatic Renal Transplant Recipient Employed in the Health Care Setting: A Case Report. Int J Angiol 2021; 31:289-291. [PMID: 36588866 PMCID: PMC9803529 DOI: 10.1055/s-0041-1725183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
During the ongoing pandemic, there have been varying presentations of coronavirus disease 2019 (COVID-19) infection, with the concern that patients who are immunosuppressed (due to underlying medical conditions and/or therapies) are at higher risk of severe disease. We report the case of an elderly renal transplant recipient working in a long-term health care facility who was being monitored by weekly surveillance testing and tested positive for COVID-19 by polymerase chain reaction (PCR) testing, despite having no clinical symptoms. He recovered with supportive care, despite being on multiple long-term immunosuppressant drugs and having multiple comorbidities. Additionally, it was found that he did not mount an antibody response, when he tested negative by serologic testing. Through this case, we wish to highlight the unique clinical scenario of asymptomatic patients who may have an underwhelming immune response to COVID-19, but may nevertheless be an important source of dissemination. We further discuss the probable mechanism of such asymptomatic presentations in immunosuppressed patients, while reinforcing the importance of self-isolation of COVID-19 patients (particularly in asymptomatic health care workers).
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Affiliation(s)
- Harsha Adnani
- The Feinstein Institute for Medical Research, Northwell Health, Manhasset, New York,Address for correspondence Harsha Adnani, MBBS The Feinstein Institute for Medical Research, Northwell Health350 Community Dr, Manhasset, NY 11030
| | - Akshay Khatri
- Division of Infectious Diseases, Department of Medicine, Northwell Health, Manhasset, New York
| | - Nirav Agrawal
- The Feinstein Institute for Medical Research, Northwell Health, Manhasset, New York
| | - Ernesto Molmenti
- Department of Surgery, North Shore University Hospital, Northwell Health, Manhasset, New York
| | - Madhu Bhaskaran
- Division of Nephrology and Transplant Nephrology, Department of Medicine, Northwell Health, Manhasset, New York
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Ahmed T, Tahir M, Low MX, Ren Y, Tawfik SA, Mayes ELH, Kuriakose S, Nawaz S, Spencer MJS, Chen H, Bhaskaran M, Sriram S, Walia S. Fully Light-Controlled Memory and Neuromorphic Computation in Layered Black Phosphorus. Adv Mater 2021; 33:e2004207. [PMID: 33205523 DOI: 10.1002/adma.202004207] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 10/06/2020] [Indexed: 06/11/2023]
Abstract
Imprinting vision as memory is a core attribute of human cognitive learning. Fundamental to artificial intelligence systems are bioinspired neuromorphic vision components for the visible and invisible segments of the electromagnetic spectrum. Realization of a single imaging unit with a combination of in-built memory and signal processing capability is imperative to deploy efficient brain-like vision systems. However, the lack of a platform that can be fully controlled by light without the need to apply alternating polarity electric signals has hampered this technological advance. Here, a neuromorphic imaging element based on a fully light-modulated 2D semiconductor in a simple reconfigurable phototransistor structure is presented. This standalone device exhibits inherent characteristics that enable neuromorphic image pre-processing and recognition. Fundamentally, the unique photoresponse induced by oxidation-related defects in 2D black phosphorus (BP) is exploited to achieve visual memory, wavelength-selective multibit programming, and erasing functions, which allow in-pixel image pre-processing. Furthermore, all-optically driven neuromorphic computation is demonstrated by machine learning to classify numbers and recognize images with an accuracy of over 90%. The devices provide a promising approach toward neurorobotics, human-machine interaction technologies, and scalable bionic systems with visual data storage/buffering and processing.
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Affiliation(s)
- Taimur Ahmed
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Muhammad Tahir
- Department of Physics, Colorado State University, Fort Collins, CO, 80523, USA
| | - Mei Xian Low
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Yanyun Ren
- Center for Advanced Optoelectronic Functional Materials Research and Key Laboratory for UV Light-Emitting Materials and Technology, Northeast Normal University, Ministry of Education, Changchun, 130024, China
| | | | - Edwin L H Mayes
- School of Science, RMIT University, Melbourne, VIC, 3001, Australia
| | - Sruthi Kuriakose
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Shahid Nawaz
- Department of Physics, University of California, Berkeley, CA, 94720, USA
| | | | - Hua Chen
- Department of Physics, Colorado State University, Fort Collins, CO, 80523, USA
- School of Advanced Materials Discovery (SAMD), Colorado State University, Fort Collins, CO, 80523, USA
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
- ARC Centre of Excellence for Transformative Meta-Optical Systems, RMIT University, Melbourne, VIC, 3001, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
- ARC Centre of Excellence for Transformative Meta-Optical Systems, RMIT University, Melbourne, VIC, 3001, Australia
| | - Sumeet Walia
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
- School of Engineering, RMIT University, Melbourne, VIC, 3001, Australia
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Perera GS, Ahmed T, Heiss L, Walia S, Bhaskaran M, Sriram S. Rapid and Selective Biomarker Detection with Conductometric Sensors. Small 2021; 17:e2005582. [PMID: 33502115 DOI: 10.1002/smll.202005582] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 11/18/2020] [Indexed: 06/12/2023]
Abstract
The biomarker detection in human body fluids is crucial as biomarkers are important in diagnosing diseases. Conventional invasive techniques for biomarker detection are associated with infection, tissue damage, and discomfort. Non-invasive devices are an attractive alternative. Here, metal oxide (oxygen-deficient zinc oxide, ZnO) based conductometric sensors with two-terminal electrodes for rapid detection of biomarkers in real-time, are presented. This platform can be engineered for non-invasive, sensitive, and on-demand selective detection of biomarkers based on surface functionalization. The three novelties in this biosensing technique include an on-demand target selection device platform, short (<10 min) incubation times, and real-time monitoring of the biomarker of interest by electrical (resistance change) measurements. Cardiac inflammatory biomarkers interleukin 6 (IL-6) and C-reactive protein (CRP) are used as the model antigens. The devices can detect 100× lower concentration of IL-6 than healthy levels in human saliva and sweat and 1000× and ≈50× lower CRP concentrations than healthy levels in human saliva and sweat, respectively. The devices show high selectivity for IL-6 and CRP antigens when tested with a mixture of biomarkers. This sensor platform can be extended to selective measurements for viruses or DNA screening, which enables a new category of compact and rapid point-of-care medical devices.
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Affiliation(s)
- Ganganath S Perera
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
| | - Taimur Ahmed
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
| | - Leah Heiss
- School of Design, RMIT University, Melbourne, Victoria, 3001, Australia
| | - Sumeet Walia
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
- School of Engineering, RMIT University, Melbourne, Victoria, 3001, Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
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13
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Jandovitz N, Nair V, Grodstein E, Molmenti E, Fahmy A, Abate M, Bhaskaran M, Teperman L. Hepatitis C-positive donor to negative recipient kidney transplantation: A real-world experience. Transpl Infect Dis 2021; 23:e13540. [PMID: 33259125 DOI: 10.1111/tid.13540] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 11/03/2020] [Accepted: 11/22/2020] [Indexed: 12/21/2022]
Abstract
BACKGROUND Several studies have shown that transplanting a hepatitis C virus (HCV)-negative recipients with a HCV-positive donor is feasible in a research setting. In February 2018, we began transplanting HCV-negative recipients with HCV-positive donors as standard of care. METHODS All patients, except those with previously cured HCV and those with cirrhosis, were consented for HCV NAT-positive donor kidneys. After transplantation, patients were tested for HCV RNA until viremic. A direct-acting antiviral (DAA) agent was prescribed based on genotype and insurance approval. Sustained virologic response (SVR) at weeks 4 and 12 was recorded. Renal function and death censored graft survival at 1 year were evaluated and compared to recipients of HCV NAT-negative kidneys. RESULTS A total of 25 HCV NAT-positive donor kidney transplants from February to October 2018 were performed. All patients received basiliximab and maintained with tacrolimus, mycophenolate mofetil, and prednisone. Median time from viremia to start of DAA was 13 (8-22) days. The most common genotype was 1a (60%), followed by 3a (28%). The most commonly prescribed DAA was ledipasvir/sofosbuvir (56%), followed by velpatasvir/sofosbuvir (32%), and then glecaprevir/pibrentasvir (12%). All patients achieved initial SVR12, except one. One patient had a mixed-genotype infection requiring retreatment to achieve SVR12. Death censored graft survival was 96%. Recipients of HCV NAT-positive organs compared to HCV NAT-negative organs received younger donors (mean 35 ± 8.9 vs 45.1 ± 15.7 years; P < .01) and spent less time on the waitlist (median 479 (93-582) vs 1808 (567-2263) days; P = .02). CONCLUSION HCV NAT-negative recipients can be safely and successfully transplanted with HCV NAT-positive donor kidneys outside of a research protocol. Access to DAA and timely administration of therapy is important and an insurance approval process within the transplant center can be beneficial to patients. A case of mixed-genotype infection was presented, and although not as common, can be successfully treated. HCV organs can expand the organ pool and should no longer be considered experimental. The use of these organs in HCV-negative recipient's decreases waiting time, have excellent outcomes, and should be considered standard of care.
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Affiliation(s)
- Nicholas Jandovitz
- Department of Pharmacy, North Shore University Hospital -Northwell Health, Manhasset, NY, USA.,Department of Surgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
| | - Vinay Nair
- Department of Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
| | - Elliot Grodstein
- Department of Surgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
| | - Ernesto Molmenti
- Department of Surgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
| | - Ahmed Fahmy
- Department of Surgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
| | - Mersema Abate
- Department of Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
| | - Madhu Bhaskaran
- Department of Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
| | - Lewis Teperman
- Department of Surgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
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14
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Khatri AM, Berlinrut I, Koshy R, Bhaskaran M. Cytomegalovirus Viremia in Renal Transplant Recipients After Influenza Vaccination. Cureus 2020; 12:e9680. [PMID: 32923273 PMCID: PMC7486015 DOI: 10.7759/cureus.9680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Vaccination with the inactivated influenza vaccine is routinely recommended for all patients before and after transplant, with reduction in complications noted in transplant recipients. The vaccine is relatively well tolerated with few mild side effects. Cytomegalovirus (CMV) infection can reactivate in both solid organ transplant and hematopoietic stem cell transplant recipients, with some patients progressing to disease. There are multiple factors known to contribute to reactivation and subsequent CMV disease, however vaccination has not been reported as a specific risk factor. We report on two renal transplant recipients who were seen to develop CMV viremia and CMV disease after receiving the Influenza vaccine. We review the literature regarding viremia occurring after vaccination in HIV patients (a similar group of immunocompromised patients).
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Affiliation(s)
| | | | - Robin Koshy
- Infectious Diseases, Northwell Health, Manhasset, USA
| | - Madhu Bhaskaran
- Nephrology and Transplant Nephrology, Northwell Health, Manhasset, USA
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15
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Nair V, Jandovitz N, Hirsch JS, Nair G, Abate M, Bhaskaran M, Grodstein E, Berlinrut I, Hirschwerk D, Cohen SL, Davidson KW, Dominello AJ, Osorio GA, Richardson S, Teperman LW, Molmenti EP. COVID-19 in kidney transplant recipients. Am J Transplant 2020; 20:1819-1825. [PMID: 32351040 PMCID: PMC7267603 DOI: 10.1111/ajt.15967] [Citation(s) in RCA: 181] [Impact Index Per Article: 45.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 04/22/2020] [Accepted: 04/25/2020] [Indexed: 01/25/2023]
Abstract
There is minimal information on coronavirus disease 2019 (COVID-19) in immunocompromised individuals. We have studied 10 patients treated at 12 adult care hospitals. Ten kidney transplant recipients tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by polymerase chain reaction, and 9 were admitted. The median age was 57 (interquartile range [IQR] 47-67), 60% were male, 40% Caucasian, and 30% Black/African American. Median time from transplant to COVID-19 testing was 2822 days (IQR 1272-4592). The most common symptom was fever, followed by cough, myalgia, chills, and fatigue. The most common chest X-ray and computed tomography abnormality was multifocal patchy opacities. Three patients had no abnormal findings. Leukopenia was seen in 20% of patients, and allograft function was stable in 50% of patients. Nine patients were on tacrolimus and a mycophenolic antimetabolite, and 70% were on prednisone. Hospitalized patients had their antimetabolite agent stopped. All hospitalized patients received hydroxychloroquine and azithromycin. Three patients died (30%), and 5 (50%) developed acute kidney injury. Kidney transplant recipients infected with COVID-19 should be monitored closely in the setting of lowered immunosuppression. Most individuals required hospitalization and presenting symptoms were similar to those of nontransplant individuals.
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Affiliation(s)
- Vinay Nair
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead, New York, USA
| | - Nicholas Jandovitz
- North Shore University Hospital, Northwell Health, Manhasset, New York, USA
| | - Jamie S. Hirsch
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead, New York, USA,Institute of Health Innovations and Outcomes Research, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, New York, USA,Department of Information Services, Northwell Health, New Hyde Park, New York, USA
| | - Gayatri Nair
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead, New York, USA
| | - Mersema Abate
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead, New York, USA
| | - Madhu Bhaskaran
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead, New York, USA
| | - Elliot Grodstein
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead, New York, USA
| | - Ilan Berlinrut
- North Shore University Hospital, Northwell Health, Manhasset, New York, USA,Long Island Jewish Medical Center, Northwell Health, New Hyde Park, New York, USA
| | - David Hirschwerk
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead, New York, USA
| | - Stuart L. Cohen
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead, New York, USA,Institute of Health Innovations and Outcomes Research, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, New York, USA
| | - Karina W. Davidson
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead, New York, USA,Institute of Health Innovations and Outcomes Research, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, New York, USA
| | - Andrew J. Dominello
- Institute of Health Innovations and Outcomes Research, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, New York, USA
| | - Gabrielle A. Osorio
- Institute of Health Innovations and Outcomes Research, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, New York, USA
| | - Safiya Richardson
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead, New York, USA,Institute of Health Innovations and Outcomes Research, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, New York, USA
| | - Lewis W. Teperman
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead, New York, USA
| | - Ernesto P. Molmenti
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead, New York, USA,Institute of Health Innovations and Outcomes Research, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, New York, USA,Correspondence Ernesto P. Molmenti
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16
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Arash A, Tawfik SA, Spencer MJS, Kumar Jain S, Arash S, Mazumder A, Mayes E, Rahman F, Singh M, Bansal V, Sriram S, Walia S, Bhaskaran M, Balendhran S. Electrically Activated UV-A Filters Based on Electrochromic MoO 3-x. ACS Appl Mater Interfaces 2020; 12:16997-17003. [PMID: 32203662 DOI: 10.1021/acsami.9b20916] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Chromism-based optical filters is a niche field of research, due to there being only a handful of electrochromic materials. Typically, electrochromic transition metal oxides such as MoO3 and WO3 are utilized in applications such as smart windows and electrochromic devices (ECD). Herein, we report MoO3-x-based electrically activated ultraviolet (UV) filters. The MoO3-x grown on indium tin oxide (ITO) substrate is mechanically assembled onto an electrically activated proton exchange membrane. Reversible H+ injection/extraction in MoO3-x is employed to switch the optical transmittance, enabling an electrically activated optical filter. The devices exhibit broadband transmission modulation (325-800 nm), with a peak of ∼60% in the UV-A range (350-392 nm). Comparable switching times of 8 s and a coloration efficiency of up to 116 cm2 C-1 are achieved.
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Affiliation(s)
- Aram Arash
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC 3001, Australia
| | | | | | - Shubhendra Kumar Jain
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC 3001, Australia
| | - Saba Arash
- Department of Physics and Astronomy, University of South Carolina, Columbia, South Carolina 29208, United States of America
| | - Aishani Mazumder
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC 3001, Australia
| | - Edwin Mayes
- RMIT Microscopy and Microanalysis Facility, School of Sciences, RMIT University, Melbourne, VIC 3001, Australia
| | - Fahmida Rahman
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC 3001, Australia
| | - Mandeep Singh
- Sir Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory (NBRL), School of Sciences, RMIT University, Melbourne, VIC 3001, Australia
| | - Vipul Bansal
- Sir Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory (NBRL), School of Sciences, RMIT University, Melbourne, VIC 3001, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC 3001, Australia
| | - Sumeet Walia
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC 3001, Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC 3001, Australia
| | - Sivacarendran Balendhran
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC 3001, Australia
- School of Physics, The University of Melbourne, Parkville, VIC 3010, Australia
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17
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Gangadharan K, Parameswaranunni R, Merzkani M, Molmenti E, Bhaskaran M. Renal Transplantation after Transcatheter Aortic Valve Replacement: Case Report. Int J Angiol 2020; 29:55-57. [PMID: 32132818 DOI: 10.1055/s-0038-1670665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
Patients with chronic kidney disease (CKD) have an increased likelihood of developing calcific aortic stenosis (AS). These patients also often suffer from multiple comorbidities, potentially making them high-risk surgical candidates and limiting their treatment options. Transcatheter aortic valve replacement (TAVR) is the recommended therapeutic approach for severe AS in patients who are not suitable candidates for surgical aortic valve replacement (SAVR). TAVR is being increasingly considered as a viable alternative to SAVR. As such, its applications in patients with CKD and other chronic diseases, as well as methods to optimize peri- and postoperative results are of great interest and significance. We present the case of a successful renal transplant procedure, performed within a year following a TAVR, in a 52-year-old man who suffered from multiple comorbidities.
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Affiliation(s)
| | | | - Massini Merzkani
- Department of Nephrology, North Shore University Hospital, Manhasset, New York
| | - Ernesto Molmenti
- Department of Surgery, North Shore University Hospital, Manhasset, New York
| | - Madhu Bhaskaran
- Department of Nephrology, North Shore University Hospital, Manhasset, New York
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18
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You X, Upadhyay A, Cheng Y, Bhaskaran M, Sriram S, Fumeaux C, Withayachumnankul W. Ultra-wideband far-infrared absorber based on anisotropically etched doped silicon. Opt Lett 2020; 45:1196-1199. [PMID: 32108804 DOI: 10.1364/ol.382458] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 01/18/2020] [Indexed: 06/10/2023]
Abstract
Far-infrared absorbers exhibiting wideband performance are in great demand in numerous applications, including imaging, detection, and wireless communications. Here, a nonresonant far-infrared absorber with ultra-wideband operation is proposed. This absorber is in the form of inverted pyramidal cavities etched into moderately doped silicon. By means of a wet-etching technique, the crystallinity of silicon restricts the formation of the cavities to a particular shape in an angle that favors impedance matching between lossy silicon and free space. Far-infrared waves incident on this absorber experience multiple reflections on the slanted lossy silicon side walls, being dissipated towards the cavity bottom. The simulation and measurement results confirm that an absorption beyond 90% can be sustained from 1.25 to 5.00 THz. Furthermore, the experiment results suggest that the absorber can operate up to at least 21.00 THz with a specular reflection less than 10% and negligible transmission.
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19
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Rahman MA, Tawfik SA, Ahmed T, Spencer MJS, Walia S, Sriram S, Bhaskaran M. Differential Work-Function Enabled Bifunctional Switching in Strontium Titanate Flexible Resistive Memories. ACS Appl Mater Interfaces 2020; 12:7326-7333. [PMID: 31976656 DOI: 10.1021/acsami.9b20585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Multifunctional electronic memories capable of demonstrating both analog and digital switching on-demand are extremely attractive for miniaturization of electronics without significant drain on energy consumption. Simultaneously translating functionality onto mechanically conformable platforms will further enhance their suitability. Here, we demonstrate the ability to engineer multifunctionality in strontium titanate (STO)-based resistive random-access memories (ReRAM) on a flexible polyimide platform. By utilizing different bottom electrodes of various work functions while the top electrode is fixed, differential work functions are induced in STO, to induce bipolar or complementary switching behaviors whenever required. This work-function difference-induced bifunctional switching on the flexible platform reveals a streamlined route for achieving flexible artificial neural networks, high density integration, and logic operation using a single ReRAM.
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Affiliation(s)
- Md Ataur Rahman
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility , RMIT University , Melbourne , Victoria 3001 , Australia
| | | | - Taimur Ahmed
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility , RMIT University , Melbourne , Victoria 3001 , Australia
| | - Michelle J S Spencer
- School of Science , RMIT University , GPO Box 2476, Melbourne , Victoria 3001 , Australia
| | - Sumeet Walia
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility , RMIT University , Melbourne , Victoria 3001 , Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility , RMIT University , Melbourne , Victoria 3001 , Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility , RMIT University , Melbourne , Victoria 3001 , Australia
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20
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Rahman F, Zavabeti A, Rahman MA, Arash A, Mazumder A, Walia S, Sriram S, Bhaskaran M, Balendhran S. Dual Selective Gas Sensing Characteristics of 2D α-MoO 3-x via a Facile Transfer Process. ACS Appl Mater Interfaces 2019; 11:40189-40195. [PMID: 31590483 DOI: 10.1021/acsami.9b11311] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Metal oxide-based gas sensor technology is promising due to their practical applications in toxic and hazardous gas detection. Orthorhombic α-MoO3 is a planar metal oxide with a unique layered structure, which can be obtained in a two-dimensional (2D) form. In the 2D form, the larger surface area-to-volume ratio of the material facilitates significantly higher interaction with gas molecules while exhibiting exceptional transport properties. The presence of oxygen vacancies results in nonstoichiometric MoO3 (MoO3-x), which further enhances the charge carrier mobility. Here, we study dual gas sensing characteristics and mechanism of 2D α-MoO3-x. Herein, conductometric dual gas sensors based on chemical vapor deposited 2D α-MoO3-x are developed and demonstrated. A facile transfer process is established to integrate the material into any arbitrary substrate. The sensors show high selectivity toward NO2 and H2S gases with response and recovery rates of 295.0 and 276.0 kΩ/s toward NO2 and 28.5 and 48.0 kΩ/s toward H2S, respectively. These gas sensors also show excellent cyclic endurance with a variation in ΔR ∼ 112 ± 1.64 and 19.5 ± 1.13 MΩ for NO2 and H2S, respectively. As such, this work presents the viability of planar 2D α-MoO3-x as a dual selective gas sensor.
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21
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Ahmed T, Walia S, Mayes ELH, Ramanathan R, Bansal V, Bhaskaran M, Sriram S, Kavehei O. Time and rate dependent synaptic learning in neuro-mimicking resistive memories. Sci Rep 2019; 9:15404. [PMID: 31659247 PMCID: PMC6817848 DOI: 10.1038/s41598-019-51700-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 10/01/2019] [Indexed: 12/27/2022] Open
Abstract
Memristors have demonstrated immense potential as building blocks in future adaptive neuromorphic architectures. Recently, there has been focus on emulating specific synaptic functions of the mammalian nervous system by either tailoring the functional oxides or engineering the external programming hardware. However, high device-to-device variability in memristors induced by the electroforming process and complicated programming hardware are among the key challenges that hinder achieving biomimetic neuromorphic networks. Here, a simple hybrid complementary metal oxide semiconductor (CMOS)-memristor approach is reported to implement different synaptic learning rules by utilizing a CMOS-compatible memristor based on oxygen-deficient SrTiO3-x (STOx). The potential of such hybrid CMOS-memristor approach is demonstrated by successfully imitating time-dependent (pair and triplet spike-time-dependent-plasticity) and rate-dependent (Bienenstosk-Cooper-Munro) synaptic learning rules. Experimental results are benchmarked against in-vitro measurements from hippocampal and visual cortices with good agreement. The scalability of synaptic devices and their programming through a CMOS drive circuitry elaborates the potential of such an approach in realizing adaptive neuromorphic computation and networks.
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Affiliation(s)
- Taimur Ahmed
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia.
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia.
| | - Sumeet Walia
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Edwin L H Mayes
- RMIT Microscopy and Microanalysis Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Rajesh Ramanathan
- Sir Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, VIC, 3001, Australia
| | - Vipul Bansal
- Sir Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, VIC, 3001, Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia.
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia.
| | - Omid Kavehei
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia.
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia.
- Faculty of Engineering, The University of Sydney, NWS, 2006, Sydney, Australia.
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22
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Nair V, Sheikh F, Hirschwerk D, Fahmy A, Bhaskaran M, Grodstein E, Winnick A, Maki R, Teperman L, Molmenti E. An unusual case of Kaposi sarcoma masquerading as cystitis in a kidney transplant recipient. Transpl Infect Dis 2019; 21:e13132. [DOI: 10.1111/tid.13132] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 05/28/2019] [Accepted: 06/09/2019] [Indexed: 12/01/2022]
Affiliation(s)
- Vinay Nair
- Department of Medicine Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset New York
| | - Fatima Sheikh
- Department of Medicine Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset New York
| | - David Hirschwerk
- Department of Medicine Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset New York
| | - Ahmed Fahmy
- Department of Surgery Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset New York
| | - Madhu Bhaskaran
- Department of Medicine Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset New York
| | - Elliot Grodstein
- Department of Surgery Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset New York
| | - Aaron Winnick
- Department of Surgery Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset New York
| | - Robert Maki
- Department of Medicine Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset New York
| | - Lewis Teperman
- Department of Surgery Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset New York
| | - Ernesto Molmenti
- Department of Surgery Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset New York
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23
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Ahmed T, Kuriakose S, Mayes ELH, Ramanathan R, Bansal V, Bhaskaran M, Sriram S, Walia S. Optically Stimulated Artificial Synapse Based on Layered Black Phosphorus. Small 2019; 15:e1900966. [PMID: 31018039 DOI: 10.1002/smll.201900966] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Indexed: 06/09/2023]
Abstract
The translation of biological synapses onto a hardware platform is an important step toward the realization of brain-inspired electronics. However, to mimic biological synapses, devices till-date continue to rely on the need for simultaneously altering the polarity of an applied electric field or the output of these devices is photonic instead of an electrical synapse. As the next big step toward practical realization of optogenetics inspired circuits that exhibit fidelity and flexibility of biological synapses, optically-stimulated synaptic devices without a need to apply polarity-altering electric field are needed. Utilizing a unique photoresponse in black phosphorus (BP), here reported is an all-optical pathway to emulate excitatory and inhibitory action potentials by exploiting oxidation-related defects. These optical synapses are capable of imitating key neural functions such as psychological learning and forgetting, spatiotemporally correlated dynamic logic and Hebbian spike-time dependent plasticity. These functionalities are also demonstrated on a flexible platform suitable for wearable electronics. Such low-power consuming devices are highly attractive for deployment in neuromorphic architectures. The manifestation of cognition and spatiotemporal processing solely through optical stimuli provides an incredibly simple and powerful platform to emulate sophisticated neural functionalities such as associative sensory data processing and decision making.
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Affiliation(s)
- Taimur Ahmed
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Sruthi Kuriakose
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Edwin L H Mayes
- RMIT Microscopy and Microanalysis Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Rajesh Ramanathan
- Sir Ian Potter NanoBioSensing Facility and NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, VIC, 3001, Australia
| | - Vipul Bansal
- Sir Ian Potter NanoBioSensing Facility and NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, VIC, 3001, Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Sumeet Walia
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
- School of Engineering, RMIT University, Melbourne, VIC, 3001, Australia
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24
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Nirantar S, Ahmed T, Ren G, Gutruf P, Xu C, Bhaskaran M, Walia S, Sriram S. Metal-Air Transistors: Semiconductor-Free Field-Emission Air-Channel Nanoelectronics. Nano Lett 2018; 18:7478-7484. [PMID: 30441900 DOI: 10.1021/acs.nanolett.8b02849] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Scattering-free transport in vacuum tubes has always been superior to solid-state transistors. It is the advanced fabrication with mass production capability at low cost which drove solid-state nanoelectronics. Here, we combine the best of vacuum tubes with advanced nanofabrication technology. We present nanoscale, metal-based, field emission air channel transistors. Comparative analysis of tungsten-, gold-, and platinum-based devices is presented. Devices are fabricated with electron beam lithography, achieving channel lengths less than 35 nm. With this small channel length, vacuum-like carrier transport is possible in air under room temperature and pressure. Source and drain electrodes have planar, symmetric, and sharp geometry. Because of this, devices operate in bidirection with voltages <2 V and current values in few tens of nanoamperes range. The experimental data shows that influential operation mechanism is Fowler-Nordheim tunnelling in tungsten and gold devices, while Schottky emission in platinum device. The presented work enables a technology where metal-based switchable nanoelectronics can be created on any dielectric surface with low energy requirements.
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Affiliation(s)
- Shruti Nirantar
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility , RMIT University , Melbourne , VIC 3000 , Australia
| | - Taimur Ahmed
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility , RMIT University , Melbourne , VIC 3000 , Australia
| | - Guanghui Ren
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility , RMIT University , Melbourne , VIC 3000 , Australia
| | - Philipp Gutruf
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility , RMIT University , Melbourne , VIC 3000 , Australia
| | - Chenglong Xu
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility , RMIT University , Melbourne , VIC 3000 , Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility , RMIT University , Melbourne , VIC 3000 , Australia
| | - Sumeet Walia
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility , RMIT University , Melbourne , VIC 3000 , Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility , RMIT University , Melbourne , VIC 3000 , Australia
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25
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Rahman F, Ahmed T, Walia S, Mayes E, Sriram S, Bhaskaran M, Balendhran S. Reversible resistive switching behaviour in CVD grown, large area MoO x. Nanoscale 2018; 10:19711-19719. [PMID: 30141809 DOI: 10.1039/c8nr04407d] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Non-volatile resistive memory devices are theorized to be the most promising pathway towards analog memory and neuromorphic computing. Two-dimensional MoO3 is a versatile planar transition metal oxide, whose properties can be readily tuned, making it anywhere from a wide bandgap semiconductor to a semi-metal. Successful integration of such a planar metal oxide into resistive memory can enable adaptive and low power memory applications. Here, we investigate the non-volatile and reversible resistive switching behaviour of oxygen deficient MoOx in a cross-point metal/insulator/metal (MIM) architecture. Layered MoOx films are synthesised using chemical vapour deposition (CVD) and reveal excellent resistive switching performance with relatively low electroforming and operating voltages. Switching ratios of ∼103 and stable data retention of >104 s are achieved. As such, this work demonstrates the viability of MoOx as a resistive memory element and paves the way for future two-dimensional resistive memory technologies.
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Affiliation(s)
- Fahmida Rahman
- Functional Materials and Microsystem Research Group and Micro Nano Research Facility, RMIT University, Melbourne, Victoria 3000, Australia.
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26
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Ahmed T, Walia S, Mayes ELH, Ramanathan R, Guagliardo P, Bansal V, Bhaskaran M, Yang JJ, Sriram S. Data related to the nanoscale structural and compositional evolution in resistance change memories. Data Brief 2018; 21:18-24. [PMID: 30310835 PMCID: PMC6176844 DOI: 10.1016/j.dib.2018.09.087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 04/26/2018] [Accepted: 09/28/2018] [Indexed: 11/30/2022] Open
Abstract
The data included in this article provides additional supplementary information on our recent publication describing “Inducing tunable switching behavior in a single memristor” [1]. Analyses of micro/nano-structural and compositional changes induced in a resistive oxide memory during resistive switching are carried out. Chromium doped strontium titanate based resistance change memories are fabricated in a capacitor-like metal-insulator-metal structure and subjected to different biasing conditions to set memory states. Transmission electron microscope based cross-sectional analyses of the memory devices in different memory states are collected and presented.
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Affiliation(s)
- Taimur Ahmed
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC 3001, Australia
| | - Sumeet Walia
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC 3001, Australia
| | - Edwin L H Mayes
- RMIT Microscopy and Microanalysis Facility, RMIT University, Melbourne, VIC 3001, Australia
| | - Rajesh Ramanathan
- Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, VIC 3001, Australia
| | - Paul Guagliardo
- Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, Perth, WA 6009, Australia
| | - Vipul Bansal
- Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, VIC 3001, Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC 3001, Australia
| | - J Joshua Yang
- Department of Electrical and Computer Engineering, University of Massachusetts, Amherst, MA 01003, USA
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC 3001, Australia
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27
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Zou W, González A, Jampaiah D, Ramanathan R, Taha M, Walia S, Sriram S, Bhaskaran M, Dominguez-Vera JM, Bansal V. Skin color-specific and spectrally-selective naked-eye dosimetry of UVA, B and C radiations. Nat Commun 2018; 9:3743. [PMID: 30254260 PMCID: PMC6156228 DOI: 10.1038/s41467-018-06273-3] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 08/28/2018] [Indexed: 12/19/2022] Open
Abstract
Spectrally-selective monitoring of ultraviolet radiations (UVR) is of paramount importance across diverse fields, including effective monitoring of excessive solar exposure. Current UV sensors cannot differentiate between UVA, B, and C, each of which has a remarkably different impact on human health. Here we show spectrally selective colorimetric monitoring of UVR by developing a photoelectrochromic ink that consists of a multi-redox polyoxometalate and an e- donor. We combine this ink with simple components such as filter paper and transparency sheets to fabricate low-cost sensors that provide naked-eye monitoring of UVR, even at low doses typically encountered during solar exposure. Importantly, the diverse UV tolerance of different skin colors demands personalized sensors. In this spirit, we demonstrate the customized design of robust real-time solar UV dosimeters to meet the specific need of different skin phototypes. These spectrally-selective UV sensors offer remarkable potential in managing the impact of UVR in our day-to-day life.
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Affiliation(s)
- Wenyue Zou
- Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, VIC, 3000, Australia
| | - Ana González
- Departamento de Química Inorgánica and Instituto de Biotecnología, Universidad de Granada, Granada, 18071, Spain
| | - Deshetti Jampaiah
- Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, VIC, 3000, Australia
| | - Rajesh Ramanathan
- Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, VIC, 3000, Australia
| | - Mohammad Taha
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3000, Australia
| | - Sumeet Walia
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3000, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3000, Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3000, Australia
| | - José M Dominguez-Vera
- Departamento de Química Inorgánica and Instituto de Biotecnología, Universidad de Granada, Granada, 18071, Spain.
| | - Vipul Bansal
- Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, VIC, 3000, Australia.
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28
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Sun M, Taha M, Walia S, Bhaskaran M, Sriram S, Shieh W, Unnithan RR. A Photonic Switch Based on a Hybrid Combination of Metallic Nanoholes and Phase-change Vanadium Dioxide. Sci Rep 2018; 8:11106. [PMID: 30038382 PMCID: PMC6056514 DOI: 10.1038/s41598-018-29476-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 07/12/2018] [Indexed: 11/11/2022] Open
Abstract
A photonic switch is an integral part of optical telecommunication systems. A plasmonic bandpass filter integrated with materials exhibiting phase transition can be used as a thermally reconfigurable optical switch. This paper presents the design and demonstration of a broadband photonic switch based on an aluminium nanohole array on quartz utilising the semiconductor-to-metal phase transition of vanadium dioxide. The fabricated switch shows an operating range over 650 nm around the optical communication C, L, and U band with maximum 20%, 23% and 26% transmission difference in switching in the C band, L band, and U band, respectively. The extinction ratio is around 5 dB in the entire operation range. This architecture is a precursor for developing micron-size photonic switches and ultra-compact modulators for thin film photonics.
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Affiliation(s)
- Miao Sun
- Electrical & Electronic Engineering Department, University of Melbourne, Parkville, 3010, Australia.
| | - Mohammad Taha
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, GPO Box 2476, Melbourne, Victoria, 3001, Australia
| | - Sumeet Walia
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, GPO Box 2476, Melbourne, Victoria, 3001, Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, GPO Box 2476, Melbourne, Victoria, 3001, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and the Micro Nano Research Facility, RMIT University, GPO Box 2476, Melbourne, Victoria, 3001, Australia
| | - William Shieh
- Electrical & Electronic Engineering Department, University of Melbourne, Parkville, 3010, Australia
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29
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Lee WSL, Ako RT, Low MX, Bhaskaran M, Sriram S, Fumeaux C, Withayachumnankul W. Dielectric-resonator metasurfaces for broadband terahertz quarter- and half-wave mirrors. Opt Express 2018; 26:14392-14406. [PMID: 29877478 DOI: 10.1364/oe.26.014392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 05/13/2018] [Indexed: 06/08/2023]
Abstract
Polarization conversion of terahertz waves is important for applications in imaging and communications. Conventional wave plates used for polarization conversion are inherently bulky and operate at discrete wavelengths. As a substitute, we employ reflective metasurfaces composed of subwavelength resonators to obtain similar functionality but with enhanced performance. More specifically, we demonstrate low-order dielectric resonators in place of commonly used planar metallic resonators to achieve high radiation efficiencies. As a demonstration of the concept, we present firstly, a quarter-wave mirror that converts 45° incident linearly polarized waves into circularly polarized waves. Next, we present a half-wave mirror that preserves the handedness of circularly polarized waves upon reflection, and in addition, rotates linearly polarized waves by 90° upon reflection. Both metasurfaces operate with high efficiency over a measurable relative bandwidth of 49% for the quarter-wave mirror and 53% for the half-wave mirror. This broadband and high efficiency capabilities of our metasurfaces will allow to leverage maximum benefits from a vast terahertz bandwidth.
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30
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Taha M, Walia S, Ahmed T, Headland D, Withayachumnankul W, Sriram S, Bhaskaran M. Insulator-metal transition in substrate-independent VO 2 thin film for phase-change devices. Sci Rep 2017; 7:17899. [PMID: 29263388 PMCID: PMC5738395 DOI: 10.1038/s41598-017-17937-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 11/24/2017] [Indexed: 11/30/2022] Open
Abstract
Vanadium has 11 oxide phases, with the binary VO2 presenting stimuli-dependent phase transitions that manifest as switchable electronic and optical features. An elevated temperature induces an insulator-to-metal transition (IMT) as the crystal reorients from a monoclinic state (insulator) to a tetragonal arrangement (metallic). This transition is accompanied by a simultaneous change in optical properties making VO2 a versatile optoelectronic material. However, its deployment in scalable devices suffers because of the requirement of specialised substrates to retain the functionality of the material. Sensitivity to oxygen concentration and larger-scale VO2 synthesis have also been standing issues in VO2 fabrication. Here, we address these major challenges in harnessing the functionality in VO2 by demonstrating an approach that enables crystalline, switchable VO2 on any substrate. Glass, silicon, and quartz are used as model platforms to show the effectiveness of the process. Temperature-dependent electrical and optical characterisation is used demonstrating three to four orders of magnitude in resistive switching, >60% chromic discrimination at infrared wavelengths, and terahertz property extraction. This capability will significantly broaden the horizon of applications that have been envisioned but remained unrealised due to the lack of ability to realise VO2 on any substrate, thereby exploiting its untapped potential.
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Affiliation(s)
- Mohammad Taha
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia.
| | - Sumeet Walia
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
| | - Taimur Ahmed
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
| | - Daniel Headland
- School of Electrical and Electronic Engineering, The University of Adelaide, South Australia, 5005, Australia
| | - Withawat Withayachumnankul
- School of Electrical and Electronic Engineering, The University of Adelaide, South Australia, 5005, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3001, Australia.
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31
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Ahmed T, Walia S, Kim J, Nili H, Ramanathan R, Mayes ELH, Lau DWM, Kavehei O, Bansal V, Bhaskaran M, Sriram S. Transparent amorphous strontium titanate resistive memories with transient photo-response. Nanoscale 2017; 9:14690-14702. [PMID: 28944813 DOI: 10.1039/c7nr04372d] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Transparent non-volatile memory devices are desirable for realizing visually-clear integrated systems for information storage. Optical transparency provides advantages in applications such as smart glass electronic devices and wearable electronics. However, achieving high transparency limits the choice of active layers as well as the electrodes; thereby, constraining device processing and performance. Here, we demonstrate bilayer transparent memory cells using room temperature deposited amorphous strontium titanate as the functional material and indium tin oxide electrodes. The entire device is fabricated on glass, making the system highly transparent (>85%) in the visible spectrum. The devices exhibit switching ratios of over two orders of magnitude with measured retention of 105 s and endurance 104 cycles. Through the cross-sectional microstructural analyses it is shown that the asymmetric interfaces and distribution of oxygen vacancies in the bilayer oxide stack are responsible for defining the bipolar resistive switching behaviors. A photoluminescence mapping technique is employed to map the evolution of oxygen vacancies and pinpoint the location of the conductive filament. A transient response to optical excitation (using UV and blue light) is demonstrated in the high resistance state which indicates their potential as multifunctional memories for future transparent electronics.
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Affiliation(s)
- Taimur Ahmed
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, Australia.
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32
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Walia S, Balendhran S, Ahmed T, Singh M, El-Badawi C, Brennan MD, Weerathunge P, Karim MN, Rahman F, Rassell A, Duckworth J, Ramanathan R, Collis GE, Lobo CJ, Toth M, Kotsakidis JC, Weber B, Fuhrer M, Dominguez-Vera JM, Spencer MJS, Aharonovich I, Sriram S, Bhaskaran M, Bansal V. Ambient Protection of Few-Layer Black Phosphorus via Sequestration of Reactive Oxygen Species. Adv Mater 2017; 29:1700152. [PMID: 28497880 DOI: 10.1002/adma.201700152] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2017] [Revised: 03/24/2017] [Indexed: 05/26/2023]
Abstract
Few-layer black phosphorous (BP) has emerged as a promising candidate for next-generation nanophotonic and nanoelectronic devices. However, rapid ambient degradation of mechanically exfoliated BP poses challenges in its practical deployment in scalable devices. To date, the strategies employed to protect BP have relied upon preventing its exposure to atmospheric conditions. Here, an approach that allows this sensitive material to remain stable without requiring its isolation from the ambient environment is reported. The method draws inspiration from the unique ability of biological systems to avoid photo-oxidative damage caused by reactive oxygen species. Since BP undergoes similar photo-oxidative degradation, imidazolium-based ionic liquids are employed as quenchers of these damaging species on the BP surface. This chemical sequestration strategy allows BP to remain stable for over 13 weeks, while retaining its key electronic characteristics. This study opens opportunities to practically implement BP and other environmentally sensitive 2D materials for electronic applications.
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Affiliation(s)
- Sumeet Walia
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Sivacarendran Balendhran
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Taimur Ahmed
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Mandeep Singh
- Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, 3000, Victoria, Australia
| | - Christopher El-Badawi
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, 2007, NSW, Australia
| | - Mathew D Brennan
- School of Science, RMIT University, Melbourne, 3001, Victoria, Australia
| | - Pabudi Weerathunge
- Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, 3000, Victoria, Australia
| | - Md Nurul Karim
- Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, 3000, Victoria, Australia
| | - Fahmida Rahman
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Andrea Rassell
- School of Media and Communication, RMIT University, Melbourne, 3000, Victoria, Australia
| | - Jonathan Duckworth
- School of Media and Communication, RMIT University, Melbourne, 3000, Victoria, Australia
| | - Rajesh Ramanathan
- Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, 3000, Victoria, Australia
| | - Gavin E Collis
- CSIRO Manufacturing, CSIRO, Bayview Avenue, Clayton, 3168, Victoria, Australia
| | - Charlene J Lobo
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, 2007, NSW, Australia
| | - Milos Toth
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, 2007, NSW, Australia
| | - Jimmy Christopher Kotsakidis
- School of Physics and Monash Centre for Atomically Thin Materials, Monash University, Clayton, 3800, Victoria, Australia
| | - Bent Weber
- School of Physics and Monash Centre for Atomically Thin Materials, Monash University, Clayton, 3800, Victoria, Australia
| | - Michael Fuhrer
- School of Physics and Monash Centre for Atomically Thin Materials, Monash University, Clayton, 3800, Victoria, Australia
| | - Jose M Dominguez-Vera
- Departamento de Química Inorganica, Instituto de Biotecnologia, Universidad de Granada, E-18071, Granada, Spain
| | | | - Igor Aharonovich
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, 2007, NSW, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, VIC, 3001, Australia
| | - Vipul Bansal
- Ian Potter NanoBioSensing Facility, NanoBiotechnology Research Laboratory, School of Science, RMIT University, Melbourne, 3000, Victoria, Australia
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33
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Lee WSL, Kaltenecker K, Nirantar S, Withayachumnankul W, Walther M, Bhaskaran M, Fischer BM, Sriram S, Fumeaux C. Terahertz near-field imaging of dielectric resonators. Opt Express 2017; 25:3756-3764. [PMID: 28241587 DOI: 10.1364/oe.25.003756] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
As an alternative to metallic resonators, dielectric resonators can increase radiation efficiencies of metasurfaces at terahertz frequencies. Such subwavelength resonators made from low-loss dielectric materials operate on the basis of oscillating displacement currents. For full control of electromagnetic waves, it is essential that dielectric resonators operate around their resonant modes. Thus, understanding the nature of these resonances is crucial towards design implementation. To this end, an array of silicon resonators on a quartz substrate is designed to operate in transmission at terahertz frequencies. The resonator dimensions are tailored to observe their low-order modes of resonance at 0.58 THz and 0.61 THz respectively. We employ a terahertz near-field imaging technique to measure the complex near-fields of this dielectric resonator array. This unique method allows direct experimental observation of the first two fundamental resonances.
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34
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Jayaschandran V, Rajendran PP, Khanal M, Krishnan P, Ramadas P, Alex A, Nambiar L, Hirschwerk DA, McGowan JP, Ali N, Basu A, Bhaskaran M, Molmenti EP. Plausible Role of Acute HIV Infection Mediated Immune Activation in Causing Renal Allograft Rejection: A Case Report. Int J Angiol 2016; 25:e12-e13. [PMID: 28031642 DOI: 10.1055/s-0034-1371760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
Current research states that AIDS pathogenesis has its roots in a chronic activation of immune system secondary to human immunodeficiency virus (HIV)-induced proliferation of T cells, B cells, NK cells, and macrophages. Immune activation due to acute HIV infection can be highly detrimental to allograft survival in a renal transplant recipient. In this report, we describe a 32-year-old African-American male patient who underwent a second live donor renal transplant, following which he developed acute allograft rejection coincident with newly acquired HIV seropositivity.
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Affiliation(s)
| | | | - Mamata Khanal
- Department of Transplant Program, North Shore University Hospital, New York
| | - Prathik Krishnan
- Department of Transplant Program, North Shore University Hospital, New York
| | - Poornima Ramadas
- Department of Transplant Program, North Shore University Hospital, New York
| | - Asha Alex
- Department of Transplant Program, North Shore University Hospital, New York
| | - Lakshmi Nambiar
- Department of Transplant Program, North Shore University Hospital, New York
| | - David A Hirschwerk
- Department of Infectious Disease Medicine, North Shore University Hospital, New York
| | - Joseph P McGowan
- Department of Infectious Disease Medicine, North Shore University Hospital, New York
| | - Nicole Ali
- Department of Transplant Program, North Shore University Hospital, New York
| | - Amit Basu
- Department of Transplant Program, North Shore University Hospital, New York
| | - Madhu Bhaskaran
- Department of Transplant Program, North Shore University Hospital, New York
| | - Ernesto P Molmenti
- Department of Transplant Program, North Shore University Hospital, New York
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35
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Nili H, Ahmed T, Walia S, Ramanathan R, Kandjani AE, Rubanov S, Kim J, Kavehei O, Bansal V, Bhaskaran M, Sriram S. Microstructure and dynamics of vacancy-induced nanofilamentary switching network in donor doped SrTiO 3-x memristors. Nanotechnology 2016; 27:505210. [PMID: 27861164 DOI: 10.1088/0957-4484/27/50/505210] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Donor doping of perovskite oxides has emerged as an attractive technique to create high performance and low energy non-volatile analog memories. Here, we examine the origins of improved switching performance and stable multi-state resistive switching in Nb-doped oxygen-deficient amorphous SrTiO3 (Nb:a-STO x ) metal-insulator-metal (MIM) devices. We probe the impact of substitutional dopants (i.e., Nb) in modulating the electronic structure and subsequent switching performance. Temperature stability and bias/time dependence of the switching behavior are used to ascertain the role of substitutional dopants and highlight their utility to modulate volatile and non-volatile behavior in a-STO x devices for adaptive and neuromorphic applications. We utilized a combination of transmission electron microscopy, photoluminescence emission properties, interfacial compositional evaluation, and activation energy measurements to investigate the microstructure of the nanofilamentary network responsible for switching. These results provide important insights into understanding mechanisms that govern the performance of donor-doped perovskite oxide-based memristive devices.
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Affiliation(s)
- Hussein Nili
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, VIC 3001, Australia
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36
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Daeneke T, Clark RM, Carey BJ, Ou JZ, Weber B, Fuhrer MS, Bhaskaran M, Kalantar-Zadeh K. Reductive exfoliation of substoichiometric MoS2 bilayers using hydrazine salts. Nanoscale 2016; 8:15252-15261. [PMID: 27491834 DOI: 10.1039/c6nr04327e] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Substoichiometric molybdenum disulphide (MoSx) nanosheets are successfully synthesised following a novel reductive route using hydrazine salts. The resulting two dimensional crystals are found to be highly monodispersed in thickness, forming exclusively 1.9 ± 0.2 nm thick bilayers. The lateral dimensions of the nanosheets are governed by the precursor bulk particle's size. Exploring a range of hydrazine derivatives with various degrees of steric hindrance leads to the conclusion that intercalation does not occur during the process and that exfoliation is instead facilitated by the reduction of Mo centres leading to the exfoliation of substoichiometric bilayers with distorted lattices. The lattice distortion is found to be persistent across all samples with XPS analysis pointing towards a S to Mo ratio of 1.2. The resulting material features an electronic bandgap of 2.1 eV, which is wider than that of pristine monolayer MoS2 with relatively longer radiative decay time.
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Affiliation(s)
- Torben Daeneke
- School of Engineering, RMIT University, 124 Latrobe Street, 3000 Melbourne, Australia.
| | - Rhiannon M Clark
- School of Engineering, RMIT University, 124 Latrobe Street, 3000 Melbourne, Australia.
| | - Benjamin J Carey
- School of Engineering, RMIT University, 124 Latrobe Street, 3000 Melbourne, Australia.
| | - Jian Zhen Ou
- School of Engineering, RMIT University, 124 Latrobe Street, 3000 Melbourne, Australia.
| | - Bent Weber
- School of Physics & Astronomy, Monash University, 20 Research Way, 3800 Clayton, Australia
| | - Michael S Fuhrer
- School of Physics & Astronomy, Monash University, 20 Research Way, 3800 Clayton, Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group, School of Engineering, RMIT University, 124 Latrobe Street, 3000 Melbourne, Australia
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Zou C, Gutruf P, Withayachumnankul W, Zou L, Bhaskaran M, Sriram S, Fumeaux C. Nanoscale TiO 2 dielectric resonator absorbers. Opt Lett 2016; 41:3391-3394. [PMID: 27472576 DOI: 10.1364/ol.41.003391] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We demonstrate a narrow-band plasmonic absorber based on a uniform array of nanoscale cylindrical dielectric resonators (DRs) on a metallic substrate at visible frequencies. Under a normally incident plane-wave excitation, the DRs resonate in their horizontal magnetic dipolar mode, which can be seen as localized plasmonic hot spots. Such a localized resonance also couples incident waves into surface plasmon polaritons (SPPs) bidirectionally, and perfect absorption is achieved by creating SPP standing waves. The simulation shows perfect absorption at 633 nm and 1.8% relative bandwidth with >90% absorption, while the measurement demonstrates maximum absorption of 90% at 636 nm. Both simulation and measurement results are analyzed with coupled mode theory. An additional numerical study elaborates on the dependence of absorption on the resonator size, period, and incidence angle.
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Gutruf P, Zou C, Withayachumnankul W, Bhaskaran M, Sriram S, Fumeaux C. Mechanically Tunable Dielectric Resonator Metasurfaces at Visible Frequencies. ACS Nano 2016; 10:133-141. [PMID: 26617198 DOI: 10.1021/acsnano.5b05954] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Devices that manipulate light represent the future of information processing. Flat optics and structures with subwavelength periodic features (metasurfaces) provide compact and efficient solutions. The key bottleneck is efficiency, and replacing metallic resonators with dielectric resonators has been shown to significantly enhance performance. To extend the functionalities of dielectric metasurfaces to real-world optical applications, the ability to tune their properties becomes important. In this article, we present a mechanically tunable all-dielectric metasurface. This is composed of an array of dielectric resonators embedded in an elastomeric matrix. The optical response of the structure under a uniaxial strain is analyzed by mechanical-electromagnetic co-simulations. It is experimentally demonstrated that the metasurface exhibits remarkable resonance shifts. Analysis using a Lagrangian model reveals that strain modulates the near-field mutual interaction between resonant dielectric elements. The ability to control and alter inter-resonator coupling will position dielectric metasurfaces as functional elements of reconfigurable optical devices.
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Affiliation(s)
| | - Chengjun Zou
- School of Electrical and Electronic Engineering, The University of Adelaide , Adelaide, South Australia 5005, Australia
| | - Withawat Withayachumnankul
- School of Electrical and Electronic Engineering, The University of Adelaide , Adelaide, South Australia 5005, Australia
- Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology , Ookayama, Merguro-ku, Tokyo 152-8552, Japan
| | | | | | - Christophe Fumeaux
- School of Electrical and Electronic Engineering, The University of Adelaide , Adelaide, South Australia 5005, Australia
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39
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Kokila M, Bhaskaran M. Structural Changes in Amyloplast During Storage of Bioprimed Corh 4 Rice Hybrid. Appl Biol Res 2016. [DOI: 10.5958/0974-4517.2016.00014.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Headland D, Nirantar S, Withayachumnankul W, Gutruf P, Abbott D, Bhaskaran M, Fumeaux C, Sriram S. Terahertz Magnetic Mirror Realized with Dielectric Resonator Antennas. Adv Mater 2015; 27:7137-7144. [PMID: 26450363 DOI: 10.1002/adma.201503069] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 08/20/2015] [Indexed: 06/05/2023]
Abstract
Single-crystal silicon is bonded to a metal-coated substrate and etched in order to form an array of microcylinder passive terahertz dielectric resonator antennas (DRAs). The DRAs exhibit a magnetic response, and hence the array behaves as an efficient artificial magnetic conductor (AMC), with potential for terahertz antenna and sensing applications.
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Affiliation(s)
- Daniel Headland
- School of Electrical & Electronic Engineering, The University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - Shruti Nirantar
- Functional Materials and Microsystems Research Group, School of Electrical and Computer Engineering, RMIT University, Melbourne, Victoria, 3000, Australia
- Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3000, Australia
| | - Withawat Withayachumnankul
- School of Electrical & Electronic Engineering, The University of Adelaide, Adelaide, South Australia, 5005, Australia
- Functional Materials and Microsystems Research Group, School of Electrical and Computer Engineering, RMIT University, Melbourne, Victoria, 3000, Australia
- Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Ookayama, 152-8552, Meguro-ku, Tokyo, Japan
| | - Philipp Gutruf
- Functional Materials and Microsystems Research Group, School of Electrical and Computer Engineering, RMIT University, Melbourne, Victoria, 3000, Australia
- Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3000, Australia
| | - Derek Abbott
- School of Electrical & Electronic Engineering, The University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group, School of Electrical and Computer Engineering, RMIT University, Melbourne, Victoria, 3000, Australia
- Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3000, Australia
| | - Christophe Fumeaux
- School of Electrical & Electronic Engineering, The University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group, School of Electrical and Computer Engineering, RMIT University, Melbourne, Victoria, 3000, Australia
- Micro Nano Research Facility, RMIT University, Melbourne, Victoria, 3000, Australia
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41
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Clark RM, Carey BJ, Daeneke T, Atkin P, Bhaskaran M, Latham K, Cole IS, Kalantar-Zadeh K. Two-step synthesis of luminescent MoS(2)-ZnS hybrid quantum dots. Nanoscale 2015; 7:16763-16772. [PMID: 26399979 DOI: 10.1039/c5nr04790k] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A surfactant assisted technique has been used to promote the exfoliation of molybdenum disulphide (MoS2) in a water-ethanol mixture, to avoid the use of harsh organic solvents, whilst still producing sufficient concentration of MoS2 in suspension. The exfoliated flakes are converted into MoS2 quantum dots (QDs), through a hydrothermal procedure. Alternatively, when the flakes are processed with precursors for zinc sulphide (ZnS) synthesis, a simultaneous break-down and composite growth is achieved. The products are separated by centrifugation, into large ZnS spheres (200-300 nm) and small MoS2-ZnS hybrid QD materials (<100 nm), of which, the latter show favorable optical properties. Two concurrent photoluminescent (PL) peaks are seen at 380 and 450 nm, which are assigned to MoS2 and ZnS components of QDs, respectively. The PL emission from MoS2-ZnS QDs is of high energy and is more intense than the bare MoS2 flakes or QDs, with a quantum yield as high as 1.96%. The emission wavelength is independent from the excitation wavelength and does not change over time. Due to such properties, the developed hybrid QDs are potentially suitable for imaging and sensing applications.
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Affiliation(s)
- Rhiannon M Clark
- School of Electrical and Computer Engineering, RMIT University, Melbourne, Victoria 3001, Australia.
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Gutruf P, Zeller E, Walia S, Nili H, Sriram S, Bhaskaran M. Stretchable and Tunable Microtectonic ZnO-Based Sensors and Photonics. Small 2015; 11:4532-4539. [PMID: 26044575 DOI: 10.1002/smll.201500729] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 05/10/2015] [Indexed: 06/04/2023]
Abstract
The concept of realizing electronic applications on elastically stretchable "skins" that conform to irregularly shaped surfaces is revolutionizing fundamental research into mechanics and materials that can enable high performance stretchable devices. The ability to operate electronic devices under various mechanically stressed states can provide a set of unique functionalities that are beyond the capabilities of conventional rigid electronics. Here, a distinctive microtectonic effect enabled oxygen-deficient, nanopatterned zinc oxide (ZnO) thin films on an elastomeric substrate are introduced to realize large area, stretchable, transparent, and ultraportable sensors. The unique surface structures are exploited to create stretchable gas and ultraviolet light sensors, where the functional oxide itself is stretchable, both of which outperform their rigid counterparts under room temperature conditions. Nanoscale ZnO features are embedded in an elastomeric matrix function as tunable diffraction gratings, capable of sensing displacements with nanometre accuracy. These devices and the microtectonic oxide thin film approach show promise in enabling functional, transparent, and wearable electronics.
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Affiliation(s)
- Philipp Gutruf
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, 3001, Victoria, Australia
| | - Eike Zeller
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, 3001, Victoria, Australia
| | - Sumeet Walia
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, 3001, Victoria, Australia
| | - Hussein Nili
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, 3001, Victoria, Australia
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, 3001, Victoria, Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group and Micro Nano Research Facility, RMIT University, Melbourne, 3001, Victoria, Australia
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Molmenti EP, Alex A, Rosen L, Alexander M, Nicastro J, Yang J, Siskind E, Alex L, Sameyah E, Bhaskaran M, Ali N, Basu A, Sachdeva M, Agorastos S, Rajendran P, Krishnan P, Ramadas P, Amodu L, Cagliani J, Rehman S, Kressel A, Sethna CB, Sotiropoulos GC, Radtke A, Sgourakis G, Schwarz R, Fishbane S, Bellucci A, Coppa G, Rilo H, Molmenti CL. Recipient Criteria Predictive of Graft Failure in Kidney Transplantation. Int J Angiol 2015; 25:29-38. [PMID: 26900309 DOI: 10.1055/s-0035-1563605] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Several classifications systems have been developed to predict outcomes of kidney transplantation based on donor variables. This study aims to identify kidney transplant recipient variables that would predict graft outcome irrespective of donor characteristics. All U.S. kidney transplant recipients between October 25,1999 and January 1, 2007 were reviewed. Cox proportional hazards regression was used to model time until graft failure. Death-censored and nondeath-censored graft survival models were generated for recipients of live and deceased donor organs. Recipient age, gender, body mass index (BMI), presence of cardiac risk factors, peripheral vascular disease, pulmonary disease, diabetes, cerebrovascular disease, history of malignancy, hepatitis B core antibody, hepatitis C infection, dialysis status, panel-reactive antibodies (PRA), geographic region, educational level, and prior kidney transplant were evaluated in all kidney transplant recipients. Among the 88,284 adult transplant recipients the following groups had increased risk of graft failure: younger and older recipients, increasing PRA (hazard ratio [HR],1.03-1.06], increasing BMI (HR, 1.04-1.62), previous kidney transplant (HR, 1.17-1.26), dialysis at the time of transplantation (HR, 1.39-1.51), hepatitis C infection (HR, 1.41-1.63), and educational level (HR, 1.05-1.42). Predictive criteria based on recipient characteristics could guide organ allocation, risk stratification, and patient expectations in planning kidney transplantation.
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Affiliation(s)
- Ernesto P Molmenti
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York; Department of Medicine, Hofstra North Shore-LIJ School of Medicine, New York
| | - Asha Alex
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York
| | - Lisa Rosen
- The Feinstein Institute for Medical Research, Hofstra North Shore-LIJ School of Medicine, New York
| | - Mohini Alexander
- Department of Medicine, Hofstra North Shore-LIJ School of Medicine, New York
| | - Jeffrey Nicastro
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York
| | - Jingyan Yang
- Mailman School of Public Health, Columbia University, New York
| | - Eric Siskind
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York
| | - Leesha Alex
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York
| | - Emil Sameyah
- The Feinstein Institute for Medical Research, Hofstra North Shore-LIJ School of Medicine, New York
| | - Madhu Bhaskaran
- Department of Medicine, Hofstra North Shore-LIJ School of Medicine, New York
| | - Nicole Ali
- Department of Medicine, Hofstra North Shore-LIJ School of Medicine, New York
| | - Amit Basu
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York
| | - Mala Sachdeva
- Department of Medicine, Hofstra North Shore-LIJ School of Medicine, New York
| | | | - Prejith Rajendran
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York
| | - Prathik Krishnan
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York
| | - Poornima Ramadas
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York
| | - Leo Amodu
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York
| | - Joaquin Cagliani
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York
| | - Sameer Rehman
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York
| | - Adam Kressel
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York
| | - Christine B Sethna
- Department of Pediatrics, Hofstra North Shore-LIJ School of Medicine, New York
| | - Georgios C Sotiropoulos
- Department of General, Visceral and Transplantation Surgery, University Hospital Essen, Essen, Germany
| | - Arnold Radtke
- Department of General and Visceral Surgery, University Hospital Muenster, Albert-Schweitzer-Campus, Muenster, Germany
| | - George Sgourakis
- Department of General Surgery, Red Cross Hospital, Athens, Greece
| | - Richard Schwarz
- Department of Medicine, Hofstra North Shore-LIJ School of Medicine, New York
| | - Steven Fishbane
- Department of Medicine, Hofstra North Shore-LIJ School of Medicine, New York
| | - Alessandro Bellucci
- Department of Medicine, Hofstra North Shore-LIJ School of Medicine, New York
| | - Gene Coppa
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York
| | - Horacio Rilo
- Department of Surgery, Hofstra North Shore-LIJ School of Medicine, New York
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Krishnan P, Ramadas P, Rajendran PP, Madhavan P, Alex A, Jayaschandran V, Humayun SG, Ali N, Sachdeva M, Flecha A, Basu A, Bhaskaran M, Molmenti EP. Effects of Parvovirus B19 Infection in Renal Transplant Recipients: A Retrospective Review of Three Cases. Int J Angiol 2015; 24:87-92. [PMID: 26060378 DOI: 10.1055/s-0034-1371759] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
Parvovirus B19 (PVB19) is a DNA virus which causes clinically relevant infection in renal transplant recipients (RTR) leading to significant morbidity. Manifestations include erythropoietin resistant anemia, proteinuria, and glomerulosclerosis in the allograft. Severe infection may require administration of intravenous immunoglobulin, reduction in immunosuppression and transfusions. The major challenge in managing and preventing the infection in RTR involves the act of balancing the decreased level of immunosuppression and the risk of rejection. The objective of this article is to understand the importance of PVB19 infection and its outcome in RTR. We reviewed the medical records of three RTR with confirmed PVB19 infection and recorded patient information including demographics, clinical and laboratory data, management, and outcome. The average time of occurrence of PVB19 infection as transplant was 8.6 weeks and they presented with symptomatic anemia. Elevated creatinine values were noted in two of them. Following treatment, anemia improved and creatinine values returned to baseline. One of them developed an early relapse and had to be treated once again similarly. We emphasize the importance of maintaining a high index of suspicion for PVB19 infection in patients with anemia in the posttransplant phase, especially in patients on higher doses of immunosuppressants. Early and proper treatment can prevent worsening clinical condition and possible effects on the allograft.
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Affiliation(s)
- Prathik Krishnan
- Department of Transplant Program, North Shore University Hospital, Boulevard, Manhasset, New York
| | - Poornima Ramadas
- Department of Transplant Program, North Shore University Hospital, Boulevard, Manhasset, New York
| | - Prejith P Rajendran
- Department of Transplant Program, North Shore University Hospital, Boulevard, Manhasset, New York
| | - Parvathy Madhavan
- Department of Transplant Program, North Shore University Hospital, Boulevard, Manhasset, New York
| | - Asha Alex
- Department of Transplant Program, North Shore University Hospital, Boulevard, Manhasset, New York
| | - Vivek Jayaschandran
- Department of Transplant Program, North Shore University Hospital, Boulevard, Manhasset, New York
| | - Shaesta G Humayun
- Department of Anesthesiology, Brookdale University Hospital and Medical Center, Boulevard, Manhasset, New York
| | - Nicole Ali
- Department of Transplant Program, North Shore University Hospital, Boulevard, Manhasset, New York
| | - Mala Sachdeva
- Department of Nephrology, North Shore University Hospital, Boulevard, Manhasset, New York
| | - Antonette Flecha
- Department of Transplant Program, North Shore University Hospital, Boulevard, Manhasset, New York
| | - Amit Basu
- Department of Transplant Program, North Shore University Hospital, Boulevard, Manhasset, New York
| | - Madhu Bhaskaran
- Department of Transplant Program, North Shore University Hospital, Boulevard, Manhasset, New York
| | - Ernesto P Molmenti
- Department of Transplant Program, North Shore University Hospital, Boulevard, Manhasset, New York
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Wang Y, Ou JZ, Chrimes AF, Carey BJ, Daeneke T, Alsaif MMYA, Mortazavi M, Zhuiykov S, Medhekar N, Bhaskaran M, Friend JR, Strano MS, Kalantar-Zadeh K. Plasmon resonances of highly doped two-dimensional MoS₂. Nano Lett 2015; 15:883-890. [PMID: 25562610 DOI: 10.1021/nl503563g] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The exhibition of plasmon resonances in two-dimensional (2D) semiconductor compounds is desirable for many applications. Here, by electrochemically intercalating lithium into 2D molybdenum disulfide (MoS2) nanoflakes, plasmon resonances in the visible and near UV wavelength ranges are achieved. These plasmon resonances are controlled by the high doping level of the nanoflakes after the intercalation, producing two distinct resonance peak areas based on the crystal arrangements. The system is also benchmarked for biosensing using bovine serum albumin. This work provides a foundation for developing future 2D MoS2 based biological and optical units.
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Affiliation(s)
- Yichao Wang
- School of Electrical and Computer Engineering, RMIT University , Melbourne, Victoria 3000, Australia
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Balendhran S, Walia S, Nili H, Sriram S, Bhaskaran M. Elemental analogues of graphene: silicene, germanene, stanene, and phosphorene. Small 2015; 11:640-52. [PMID: 25380184 DOI: 10.1002/smll.201402041] [Citation(s) in RCA: 273] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Revised: 09/09/2014] [Indexed: 05/22/2023]
Abstract
The fascinating electronic and optoelectronic properties of free-standing graphene has led to the exploration of alternative two-dimensional materials that can be easily integrated with current generation of electronic technologies. In contrast to 2D oxide and dichalcogenides, elemental 2D analogues of graphene, which include monolayer silicon (silicene), are fast emerging as promising alternatives, with predictions of high degree of integration with existing technologies. This article reviews this emerging class of 2D elemental materials - silicene, germanene, stanene, and phosphorene--with emphasis on fundamental properties and synthesis techniques. The need for further investigations to establish controlled synthesis techniques and the viability of such elemental 2D materials is highlighted. Future prospects harnessing the ability to manipulate the electronic structure of these materials for nano- and opto-electronic applications are identified.
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Affiliation(s)
- Sivacarendran Balendhran
- Functional Materials and Microsystems Research Group, RMIT University, Melbourne, Victoria, 3001, Australia
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47
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Walia S, Shah AK, Stoddart PR, Bhaskaran M, Sriram S. Electric field induced surface-enhanced Raman spectroscopy for multianalyte detection. Phys Chem Chem Phys 2015; 17:7095-9. [DOI: 10.1039/c4cp04912h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
This work demonstrates the ability to detect and isolate an analyte from a multianalyte mixture by SERS sensing.
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Affiliation(s)
- Sumeet Walia
- Functional Materials and Microsystems Research Group
- RMIT University
- Melbourne
- Australia
- Micro Nano Research Facility
| | - Aditya K. Shah
- Functional Materials and Microsystems Research Group
- RMIT University
- Melbourne
- Australia
- Micro Nano Research Facility
| | - Paul R. Stoddart
- Faculty of Engineering and Industrial Science
- Swinburne University of Technology
- Hawthorn
- Australia
| | - Madhu Bhaskaran
- Functional Materials and Microsystems Research Group
- RMIT University
- Melbourne
- Australia
- Micro Nano Research Facility
| | - Sharath Sriram
- Functional Materials and Microsystems Research Group
- RMIT University
- Melbourne
- Australia
- Micro Nano Research Facility
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48
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Madhavan P, Jairath S, Sukumaran N, Sagar A, Molmenti E, Natarajan B, Basu A, Ali N, Bhaskaran M. Kidney transplant access in the southeast: middle view. Am J Transplant 2014; 14:2669-70. [PMID: 25219445 DOI: 10.1111/ajt.12980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- P Madhavan
- North Shore LIJ Health System, Renal Transplant Center, New York, NY
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49
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Siskind E, Maloney C, Akerman M, Alex A, Ashburn S, Barlow M, Siskind T, Bhaskaran M, Ali N, Basu A, Molmenti E, Ortiz J. An analysis of pancreas transplantation outcomes based on age groupings--an update of the UNOS database. Clin Transplant 2014; 28:990-4. [PMID: 24954160 DOI: 10.1111/ctr.12407] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/17/2014] [Indexed: 12/27/2022]
Abstract
INTRODUCTION Previously, increasing age has been a part of the exclusion criteria used when determining eligibility for a pancreas transplant. However, the analysis of pancreas transplantation outcomes based on age groupings has largely been based on single-center reports. METHODS A UNOS database review of all adult pancreas and kidney-pancreas transplants between 1996 and 2012 was performed. Patients were divided into groups based on age categories: 18-29 (n = 1823), 30-39 (n = 7624), 40-49 (n = 7967), 50-59 (n = 3160), and ≥60 (n = 280). We compared survival outcomes and demographic variables between each age grouping. RESULTS Of the 20 854 pancreas transplants, 3440 of the recipients were 50 yr of age or above. Graft survival was consistently the greatest in adults 40-49 yr of age. Graft survival was least in adults age 18-29 at one-, three-, and five-yr intervals. At 10- and 15-yr intervals, graft survival was the poorest in adults >60 yr old. Patient survival and age were found to be inversely proportional; as the patient population's age increased, survival decreased. CONCLUSION Pancreas transplants performed in patients of increasing age demonstrate decreased patient and graft survival when compared to pancreas transplants in patients <50 yr of age.
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Affiliation(s)
- Eric Siskind
- Department of Transplantation, North Shore Long Island Jewish Health System, Hofstra University School of Medicine, Manhasset, NY, USA
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50
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Siskind E, Maloney C, Ashburn S, Akerman M, Siskind T, Goldberg L, Bhaskaran M, Basu A, Molmenti E, Ortiz J. The use of venous jump grafts in pancreatic transplantation - no difference in patient or allograft outcomes - an update of the UNOS database. Clin Transplant 2014; 28:883-8. [PMID: 24930804 DOI: 10.1111/ctr.12397] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/11/2014] [Indexed: 12/17/2022]
Abstract
Venous jump grafts are used in pancreas transplantation to salvage a pancreas with a short portal vein or to facilitate an easier anastomosis. There have been no large studies evaluating the safety of venous jump grafts in pancreas transplantation. We analyzed the UNOS database to determine whether venous jump grafts are associated with graft loss or patient death. Data from UNOS on all adult pancreas transplant recipients 1996-2012 were analyzed. Venous extension grafts were used in 2657 cases; they were not in 18 124. Kaplan-Meier/product-limit estimates analysis demonstrated similar patient survival (p < 0.641) and death-censored graft survival (p < 0.351) at one, three, five,10, and 15 yr between subjects with and without venous jump grafts. There was a statistically significant difference in one-yr unadjusted patient survival between the venous extension graft (94.9%) and the no-venous extension graft (95.8%) groups (p < 0.045) and a borderline difference in one-yr graft survival between the venous extension graft (84.1%) and the no-venous extension graft (82.6%) groups (p < 0.055). There was no significant difference in patient survival or allograft survival at the three-, five-, 10-, and 15-yr intervals. The use of venous jump grafts is not associated with increased graft loss or mortality.
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Affiliation(s)
- Eric Siskind
- Department of Transplantation, North Shore Long Island Jewish Health System, Hofstra University School of Medicine, Manhasset, NY, USA
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