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Unnikrishnan G, Ilzhöfer P, Scholz A, Hölzl C, Götzelmann A, Gupta RK, Zhao J, Krauter J, Weber S, Makki N, Büchler HP, Pfau T, Meinert F. Coherent Control of the Fine-Structure Qubit in a Single Alkaline-Earth Atom. Phys Rev Lett 2024; 132:150606. [PMID: 38682979 DOI: 10.1103/physrevlett.132.150606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Accepted: 03/11/2024] [Indexed: 05/01/2024]
Abstract
We report on the first realization of a novel neutral atom qubit encoded in the spin-orbit coupled metastable states ^{3}P_{0} and ^{3}P_{2} of a single ^{88}Sr atom trapped in an optical tweezer. Raman coupling of the qubit states promises rapid single-qubit rotations on par with the fast Rydberg-mediated two-body gates. We demonstrate preparation, readout, and coherent control of the qubit. In addition to driving Rabi oscillations bridging an energy gap of more than 17 THz using a pair of phase-locked clock lasers, we also carry out Ramsey spectroscopy to extract the transverse qubit coherence time T_{2}. When the tweezer is tuned into magic trapping conditions, which is achieved in our setup by tuning the tensor polarizability of the ^{3}P_{2} state via an external control magnetic field, we measure T_{2}=1.2 ms. A microscopic quantum mechanical model is used to simulate our experiments including dominant noise sources. We identify the main constraints limiting the observed coherence time and project improvements to our system in the immediate future. Our Letter opens the door for a so-far-unexplored qubit encoding concept for neutral atom-based quantum computing.
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Affiliation(s)
- G Unnikrishnan
- 5. Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
| | - P Ilzhöfer
- 5. Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
| | - A Scholz
- 5. Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
| | - C Hölzl
- 5. Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
| | - A Götzelmann
- 5. Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
| | - R K Gupta
- 5. Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
| | - J Zhao
- 5. Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
| | - J Krauter
- 5. Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
| | - S Weber
- Institute for Theoretical Physics III and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
| | - N Makki
- Institute for Theoretical Physics III and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
| | - H P Büchler
- Institute for Theoretical Physics III and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
| | - T Pfau
- 5. Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
| | - F Meinert
- 5. Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
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Satheesh Kumar B, Roshith K, Unnikrishnan G, K.S SK. Metal organic framework enroutes to mechanically stable and high proton conductive polybenzimidazole membranes. POLYMER 2023. [DOI: 10.1016/j.polymer.2023.125904] [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: 03/31/2023]
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Nashi S, Polavarapu K, Bardhan M, Anjanappa RM, Preethish-Kumar V, Vengalil S, Padmanabha H, Geetha TS, Prathyusha PV, Ramprasad V, Joshi A, Chawla T, Unnikrishnan G, Sharma P, Huddar A, Uppilli B, Thomas A, Baskar D, Mathew S, Menon D, Arunachal G, Faruq M, Thangaraj K, Nalini A. Genotype-phenotype correlation and natural history study of dysferlinopathy: a single-centre experience from India. Neurogenetics 2023; 24:43-53. [PMID: 36580222 DOI: 10.1007/s10048-022-00707-3] [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] [Received: 10/11/2022] [Accepted: 12/15/2022] [Indexed: 12/30/2022]
Abstract
Dysferlinopathies are a group of limb-girdle muscular dystrophies causing significant disability in the young population. There is a need for studies on large cohorts to describe the clinical, genotypic and natural history in our subcontinent. To describe and correlate the clinical, genetic profile and natural history of genetically confirmed dysferlinopathies. We analysed a retrospective cohort of patients with dysferlinopathy from a single quaternary care centre in India. A total of 124 patients with dysferlinopathy were included (40 females). Median age at onset and duration of illness were 21 years (range, 13-50) and 48 months (range, 8-288), respectively. The average follow-up period was 60 months (range, 12-288). Fifty-one percent had LGMD pattern of weakness at onset; 23.4% each had Miyoshi and proximo-distal type while isolated hyperCKemia was noted in 1.6%. About 60% were born to consanguineous parents and 26.6% had family history of similar illness. Twenty-three patients (18.6%) lost ambulation at follow-up; the median time to loss of independent ambulation was 120 months (range, 72-264). Single-nucleotide variants (SNVs) constituted 78.2% of patients; INDELs 14.5% and 7.3% had both SNVs and INDELs. Earlier age at onset was noted with SNVs. There was no correlation between the other clinical parameters and ambulatory status with the genotype. Thirty-seven (45.7%) novel pathogenic/likely pathogenic (P/LP) variants were identified out of a total of 81 variations. The c.3191G > A variant was the most recurrent mutation. Our cohort constitutes a clinically and genetically heterogeneous group of dysferlinopathies. There is no significant correlation between the clinico-genetic profile and the ambulatory status.
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Affiliation(s)
- Saraswati Nashi
- Department of Neurology, Neuroscience Faculty Center, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, 560029, India
| | - Kiran Polavarapu
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Canada
| | - Mainak Bardhan
- Department of Neurology, Neuroscience Faculty Center, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, 560029, India
| | - Ram Murthy Anjanappa
- Department of Neurology, Neuroscience Faculty Center, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, 560029, India
| | - Veeramani Preethish-Kumar
- Department of Neurology, Neuroscience Faculty Center, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, 560029, India
| | - Seena Vengalil
- Department of Neurology, Neuroscience Faculty Center, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, 560029, India
| | - Hansashree Padmanabha
- Department of Neurology, Neuroscience Faculty Center, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, 560029, India
| | | | - P V Prathyusha
- Department of Biostatistics, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, India
| | | | - Aditi Joshi
- CSIR-Institute of Genomics and Integrative Biology (IGIB), Delhi, India
| | - Tanushree Chawla
- Department of Neurology, Neuroscience Faculty Center, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, 560029, India
| | - Gopikirshnan Unnikrishnan
- Department of Neurology, Neuroscience Faculty Center, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, 560029, India
| | - Pooja Sharma
- CSIR-Institute of Genomics and Integrative Biology (IGIB), Delhi, India
| | - Akshata Huddar
- Department of Neurology, Neuroscience Faculty Center, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, 560029, India
| | | | - Abel Thomas
- Department of Neurology, Neuroscience Faculty Center, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, 560029, India
| | - Dipti Baskar
- Department of Neurology, Neuroscience Faculty Center, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, 560029, India
| | - Susi Mathew
- CSIR-Institute of Genomics and Integrative Biology (IGIB), Delhi, India
| | - Deepak Menon
- Department of Neurology, Neuroscience Faculty Center, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, 560029, India
| | - Gautham Arunachal
- Department of Human Genetics, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, India
| | - Mohammed Faruq
- CSIR-Institute of Genomics and Integrative Biology (IGIB), Delhi, India
| | | | - Atchayaram Nalini
- Department of Neurology, Neuroscience Faculty Center, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, 560029, India.
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Sunitha K, Mahesh S, Suchithra C, Unnikrishnan G, Reghunadhan Nair CP. Comb like amphiphilic graft copolymers bearing PDMS and PEO side chains: synthesis and solvent assisted self-assembly behavior. J Polym Res 2022. [DOI: 10.1007/s10965-022-03128-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Unnikrishnan G, Beulenkamp C, Zhang D, Zamarski KP, Landini M, Nägerl HC. Long distance optical transport of ultracold atoms: A compact setup using a Moiré lens. Rev Sci Instrum 2021; 92:063205. [PMID: 34243520 DOI: 10.1063/5.0049320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 05/26/2021] [Indexed: 06/13/2023]
Abstract
We present a compact and robust setup to optically transport ultracold atoms over long distances. Using a focus-tunable moiré lens that has recently appeared in the market, we demonstrate transport of up to a distance of 465 mm. A transfer efficiency of 70% is achieved with a negligible temperature change at 11 μK. With its high thermal stability and low astigmatism, the moiré lens is superior to fluid-based varifocal lenses. It is much more compact and stable than a lens mounted on a linear translation stage, allowing for simplified experimental setups.
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Affiliation(s)
- G Unnikrishnan
- Institut für Experimentalphysik und Zentrum für Quantenphysik, Universität Innsbruck, 6020 Innsbruck, Austria
| | - C Beulenkamp
- Institut für Experimentalphysik und Zentrum für Quantenphysik, Universität Innsbruck, 6020 Innsbruck, Austria
| | - D Zhang
- Institut für Experimentalphysik und Zentrum für Quantenphysik, Universität Innsbruck, 6020 Innsbruck, Austria
| | - K P Zamarski
- Institut für Experimentalphysik und Zentrum für Quantenphysik, Universität Innsbruck, 6020 Innsbruck, Austria
| | - M Landini
- Institut für Experimentalphysik und Zentrum für Quantenphysik, Universität Innsbruck, 6020 Innsbruck, Austria
| | - H-C Nägerl
- Institut für Experimentalphysik und Zentrum für Quantenphysik, Universität Innsbruck, 6020 Innsbruck, Austria
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Shafeeq VH, Unnikrishnan G. Matrix-filler interactions and solvent sorption features of nanohydroxyapatite (nHA) embedded ethylene-co-vinyl acetate (EVA)-millable polyurethane (MPU) blends. Phys Chem Chem Phys 2020; 22:23627-23636. [PMID: 33048089 DOI: 10.1039/d0cp04275g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the solvent sorption features and matrix filler interactions of nanohydroxyapatite (nHA) embedded ethylene-co-vinyl acetate (EVA)-millable polyurethane (MPU) blends, using toluene, xylene, and t-butylacetate as probe molecules. The EVA/MPU blends were initially loaded with different quantities of n-HA, and the interfacial interactions were evaluated through FTIR and XRD techniques. The modulation of solvent resistance was subsequently examined in terms of filler loading, temperature and molar volume of the probes. With an increase in the amount of nHA, the solvent resistance of the matrix has been found to be enhanced, with the mechanism of transport regularly deviating from the conventional Fickian mode normally followed by elastomer matrices. The Flory-Rehner equation was employed to compute the molecular mass between crosslinks (Mc) and the crosslink density (γ). The observed enhancement in the crosslink density and the degree of reinforcement has been attributed to the increased polar-polar interactions after nHA loading into the matrix. The experimentally obtained values of Mc have been compared with phantom and affine models, to identify the type of deformation happening under solvent stress. The reinforcement effect within the matrix, as a function of filler loading, has been verified by using the Kraus equation. The swelling resistance of the composites has also been verified in biological fluids in view of the possible biofield applications of the composites.
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Affiliation(s)
- V H Shafeeq
- Polymer Science and Technology Research Laboratory, Department of Chemistry, National Institute of Technology Calicut, Kerala 673607, India.
| | - G Unnikrishnan
- Polymer Science and Technology Research Laboratory, Department of Chemistry, National Institute of Technology Calicut, Kerala 673607, India.
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Shafeeq VH, Unnikrishnan G. Experimental and theoretical evaluation of mechanical, thermal and morphological features of EVA-millable polyurethane blends. J Polym Res 2020. [DOI: 10.1007/s10965-020-2027-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Kumar B. S, Sana B, Unnikrishnan G, Jana T, Kumar K. S. S. Polybenzimidazole co-polymers: their synthesis, morphology and high temperature fuel cell membrane properties. Polym Chem 2020. [DOI: 10.1039/c9py01403a] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Polybenzimidazole (PBI) random co-polymers containing alicyclic and aromatic backbones were synthesized using two different dicarboxylic acids (viz., cyclohexane dicarboxylic acid and terephthalic acid) by varying their molar ratios.
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Affiliation(s)
- Satheesh Kumar B.
- Polymers and Special Chemicals Division
- Vikram Sarabhai Space Centre
- Thiruvananthapuram-22
- India
| | | | | | - Tushar Jana
- School of Chemistry
- University of Hyderabad
- Hyderabad
- India
| | - Santhosh Kumar K. S.
- Polymers and Special Chemicals Division
- Vikram Sarabhai Space Centre
- Thiruvananthapuram-22
- India
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Satheesh Kumar B, Sana B, Unnikrishnan G, Jana T, Santhosh Kumar K. Nano-ordered aromatic/alicyclic polybenzimidazole blend membranes. REACT FUNCT POLYM 2020. [DOI: 10.1016/j.reactfunctpolym.2019.06.020] [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: 10/26/2022]
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Vintu M, Unnikrishnan G. Indolocarbazole based polymer coated super adsorbent polyurethane sponges for oil/organic solvent removal. J Environ Manage 2019; 248:109344. [PMID: 31466186 DOI: 10.1016/j.jenvman.2019.109344] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [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: 05/12/2019] [Revised: 07/13/2019] [Accepted: 07/30/2019] [Indexed: 06/10/2023]
Abstract
The synthesis of an indolocarbazole-fluorene based conjugated polymer (ICZP6), by Sonogashira coupling reaction, has been presented. The ICZP6 has then been integrated with a nano iron oxide embedded polyurethane foam (ICZP6PUF) to develop a promising adsorbent for oil/organic contaminants in aqueous systems. The anchoring ability of ICZP6 on to iron oxide PU sponge switches on significant hydrophobicity within the whole molecular assembly. The cooperative effects of ICZP6-iron oxide- PU sponge system have been highlighted in terms of structural, microscopic and wettability characteristics. The heterogeneity and hierarchical porous structure of the system offer a high adsorption capability for different types of oils and organic contaminants in water, typically in the range of 100-240 gg-1. The performance of ICZP6PUF has been confirmed by the fast (within 5-10s) and choosy removal of selected oils and organic solvents from polluted water with the aid of an external magnetic field. The adsorbed materials (oil/organic solvents) can be separated from the adsorbent by simple mechanical squeezing without causing any structural deformation or performance deterioration; with a reusability of the system over 50 cycles. The adsorption isotherm has been found to fit well with the Langmuir model with R2 = 0.9484. To extent the scope of the ICZP6PUF hybrid, an integrative logic gate has been designed.
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Affiliation(s)
- M Vintu
- Department of Chemistry, Polymer Science and Technology Research Laboratory, National Institute of Technology Calicut, NIT Campus, Calicut, 673601, Kerala, India
| | - G Unnikrishnan
- Department of Chemistry, Polymer Science and Technology Research Laboratory, National Institute of Technology Calicut, NIT Campus, Calicut, 673601, Kerala, India.
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Satheesh Kumar B, Sana B, Unnikrishnan G, Jana T, Santhosh Kumar KS. Polybenzimidazole as proton conducting filler in polydimethylsiloxane: Enhanced oxidative stability and membrane properties. J Appl Polym Sci 2019. [DOI: 10.1002/app.48151] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- B. Satheesh Kumar
- Polymers and Special Chemicals DivisionVikram Sarabhai Space Centre Thiruvananthapuram India
| | | | | | - Tushar Jana
- School of ChemistryUniversity of Hyderabad Hyderabad India
| | - K. S. Santhosh Kumar
- Polymers and Special Chemicals DivisionVikram Sarabhai Space Centre Thiruvananthapuram India
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Vintu M, Rajan VK, Unnikrishnan G, Muraleedharan K. Suzuki coupling derived indolocarbazole based macromolecule as a solid phase/solution phase sensor for Hg2+: Experimental and theoretical explorations. Eur Polym J 2019. [DOI: 10.1016/j.eurpolymj.2019.02.033] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Popp KL, Xu C, Yuan A, Hughes JM, Unnikrishnan G, Reifman J, Bouxsein ML. Trabecular microstructure is influenced by race and sex in Black and White young adults. Osteoporos Int 2019; 30:201-209. [PMID: 30397770 DOI: 10.1007/s00198-018-4729-9] [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] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 10/01/2018] [Indexed: 10/27/2022]
Abstract
UNLABELLED Lower fracture rates in Black men and women compared to their White counterparts are incompletely understood. High-resolution imaging specific to trabecular bone may provide insight. Black participants have enhanced trabecular morphology. These differences may contribute to the lower fracture risk in Black versus White individuals. INTRODUCTION Lower fracture rates in Black men and women compared to their White counterparts may be explained by favorable bone microstructure in Black individuals. Individual trabecular segmentation (ITS) analysis, which characterizes the alignment and plate- and rod-like nature of trabecular bone using high-resolution peripheral quantitative computed tomography (HR-pQCT), may provide insight into trabecular differences by race/ethnic origin. PURPOSE We determined differences in trabecular bone microarchitecture, connectivity, and alignment according to race/ethnic origin and sex in young adults. METHODS We analyzed HR-pQCT scans of 184 adult (24.2 ± 3.4 years) women (n = 51 Black, n = 50 White) and men (n = 34 Black, n = 49 White). We used ANCOVA to compare bone outcomes, and adjusted for age, height, and weight. RESULTS Overall, the effect of race on bone outcomes did not differ by sex, and the effect of sex on bone outcomes did not differ by race. After adjusting for covariates, Black participants and men of both races had greater trabecular plate volume fraction, plate thickness, plate number density, plate surface area, and greater axial alignment of trabeculae, leading to higher trabecular bone stiffness compared to White participants and women, respectively (p < 0.05 for all). CONCLUSION These findings demonstrate that more favorable bone microarchitecture in Black individuals compared to White individuals and in men compared to women is not unique to the cortical bone compartment. Enhanced plate-like morphology and greater trabecular axial alignment, established in young adulthood, may contribute to the improved bone strength and lower fracture risk in Black versus White individuals and in men compared to women.
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Affiliation(s)
- K L Popp
- Endocrine Unit, Massachusetts General Hospital, 50 Blossom Street, THR-1051, Boston, MA, 02114, USA.
- Department of Medicine, Harvard Medical School, 25 Shattuck St, Boston, MA, 02155, USA.
- Military Performance Division, United States Army Research Institute of Environmental Medicine, 10 General Greene Ave, Natick, MA, 01760, USA.
| | - C Xu
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advance Technology Research Center, United States Army Medical Research and Materiel Command, Fort Detrick, MD, 21702, USA
| | - A Yuan
- Endocrine Unit, Massachusetts General Hospital, 50 Blossom Street, THR-1051, Boston, MA, 02114, USA
| | - J M Hughes
- Military Performance Division, United States Army Research Institute of Environmental Medicine, 10 General Greene Ave, Natick, MA, 01760, USA
| | - G Unnikrishnan
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advance Technology Research Center, United States Army Medical Research and Materiel Command, Fort Detrick, MD, 21702, USA
| | - J Reifman
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advance Technology Research Center, United States Army Medical Research and Materiel Command, Fort Detrick, MD, 21702, USA
| | - M L Bouxsein
- Endocrine Unit, Massachusetts General Hospital, 50 Blossom Street, THR-1051, Boston, MA, 02114, USA
- Center for Advanced Orthopedic Studies, Beth Israel Deaconess Medical Center, and Department of Orthopedic Surgery, Harvard Medical School, One Overland Street, Boston, MA, 02215, USA
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Vintu M, Unnikrishnan G, Shiju E, Chandrasekharan K. Indolo[3,2-b]carbazole-based poly(arylene ethynylene)s through Sonogashira coupling for optoelectronic and sensing applications. J Appl Polym Sci 2018. [DOI: 10.1002/app.46940] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- M. Vintu
- Department of Chemistry; Polymer Science and Technology Research Laboratory, National Institute of Technology; Calicut 673601 Kerala India
| | - G. Unnikrishnan
- Department of Chemistry; Polymer Science and Technology Research Laboratory, National Institute of Technology; Calicut 673601 Kerala India
| | - E. Shiju
- Department of Physics; Laser and Nonlinear Optics Laboratory, National Institute of Technology; Calicut 673601 Kerala India
| | - K. Chandrasekharan
- Department of Physics; Laser and Nonlinear Optics Laboratory, National Institute of Technology; Calicut 673601 Kerala India
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Sundaramurthy A, Skotak M, Alay E, Unnikrishnan G, Mao H, Duan X, Williams ST, Harding TH, Chandra N, Reifman J. Assessment of the Effectiveness of Combat Eyewear Protection Against Blast Overpressure. J Biomech Eng 2018; 140:2677751. [PMID: 29677280 DOI: 10.1115/1.4039823] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Indexed: 11/08/2022]
Abstract
It is unclear whether combat eyewear used by U. S. Service members is protective against blast overpressures (BOPs) caused by explosive devices. Here, we investigated the mechanisms by which BOP bypasses eyewear and increases eye surface pressure. We performed experiments and developed three-dimensional (3D) finite element (FE) models of a head form (HF) equipped with an advanced combat helmet (ACH) and with no eyewear, spectacles, or goggles in a shock tube at three BOPs and five head orientations relative to the blast wave. Overall, we observed good agreement between experimental and computational results, with average discrepancies in impulse and peak-pressure values of less than 15% over 90 comparisons. In the absence of eyewear and depending on the head orientation, we identified three mechanisms that contributed to pressure loading on the eyes. Eyewear was most effective at 0 deg orientation, with pressure attenuation ranging from 50 (spectacles) to 80% (goggles) of the peak pressures observed in the no-eyewear configuration. Spectacles and goggles were considerably less effective when we rotated the HF in the counter-clockwise direction around the superior-inferior axis of the head. Surprisingly, at certain orientations, spectacles yielded higher maximum pressures (80%) and goggles yielded larger impulses (150%) than those observed without eyewear. The findings from this study will aid in the design of eyewear that provides better protection against BOP.
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Affiliation(s)
- A Sundaramurthy
- Department of Defense, Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Materiel Command, 504 Scott Street, Fort Detrick, MD 21702 e-mail:
| | - M Skotak
- Department of Biomedical Engineering, Center for Injury Biomechanics, Materials and Medicine, New Jersey Institute of Technology, University Heights, Newark, NJ 07102 e-mail:
| | - E Alay
- Department of Biomedical Engineering, Center for Injury Biomechanics, Materials and Medicine, New Jersey Institute of Technology, University Heights, Newark, NJ 07102 e-mail:
| | - G Unnikrishnan
- Department of Defense, Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Materiel Command, 504 Scott Street, Fort Detrick, MD 21702 e-mail:
| | - H Mao
- Department of Defense, Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Materiel Command, 504 Scott Street, Fort Detrick, MD 21702 e-mail:
| | - X Duan
- Department of Defense, Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Materiel Command, 504 Scott Street, Fort Detrick, MD 21702 e-mail:
| | - S T Williams
- Visual Protection and Performance Division, U.S. Army Aeromedical Research Laboratory, Bldg. 6901, Farrel Road, Fort Rucker, AL 36362 e-mail:
| | - T H Harding
- Visual Protection and Performance Division, U.S. Army Aeromedical Research Laboratory, Bldg. 6901, Farrel Road, Fort Rucker, AL 36362 e-mail:
| | - N Chandra
- Department of Biomedical Engineering, Center for Injury Biomechanics, Materials and Medicine, New Jersey Institute of Technology, University Heights, Newark, NJ 07102 e-mail:
| | - J Reifman
- Department of Defense, Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Materiel Command, 504 Scott Street, Fort Detrick, MD 21702 e-mail:
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17
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Jayadevan J, Unnikrishnan G. Novel membranes from physico-chemically modified deproteinized natural rubber latex: development, characterisation and drug permeation. NEW J CHEM 2018. [DOI: 10.1039/c8nj01523f] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Novel blend membranes from physico-chemically modified deproteinized natural rubber latex for drug release applications.
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Affiliation(s)
- Janisha Jayadevan
- Polymer Science and Technology Research Laboratory
- Dept. of Chemistry
- National Institute of Technology Calicut
- NITC Campus
- Kozhikode
| | - G. Unnikrishnan
- Polymer Science and Technology Research Laboratory
- Dept. of Chemistry
- National Institute of Technology Calicut
- NITC Campus
- Kozhikode
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18
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Abstract
We report the modulation of dielectric and dynamic mechanical features of silicone rubber (SR), the extensively employed biocompatible elastomer, by embedding it with nano-hydroxylapatite (n-HA) particles.
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Affiliation(s)
- M. Bindu
- Dept. of Chemistry
- National Institute of Technology
- Calicut-673601
- India
| | - G. Unnikrishnan
- Dept. of Chemistry
- National Institute of Technology
- Calicut-673601
- India
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19
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Sunitha K, Bhuvaneswari S, Mathew D, Unnikrishnan G, Nair CPR. Comb Polymer Network of Polydimethylsiloxane with a Novolac Stem: Synthesis via Click Coupling and Surface Morphology Architecturing by Solvents. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b02046] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | - G. Unnikrishnan
- Department
of Chemistry, National Institute of Technology, Calicut 673601, India
| | - C. P. Reghunadhan Nair
- Department
of Polymer Science and Rubber Technology, Cochin University of Science and Technology, Cochin 682022, India
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20
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Sabarish R, Unnikrishnan G. Synthesis, characterization and catalytic activity of hierarchical ZSM-5 templated by carboxymethyl cellulose. POWDER TECHNOL 2017. [DOI: 10.1016/j.powtec.2017.07.041] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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21
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Kumar S, Nando GB, Nair S, Unnikrishnan G, Sreejesh A, Chattopadhyay S. EFFECT OF ORGANICALLY MODIFIED MONTMORILLONITE CLAY ON MORPHOLOGICAL, PHYSICOMECHANICAL, THERMAL STABILITY, AND WATER VAPOR TRANSMISSION RATE PROPERTIES OF BIIR-CO RUBBER NANOCOMPOSITE. Rubber Chemistry and Technology 2015. [DOI: 10.5254/rct.14.85996] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
ABSTRACT
Rubber nanocomposites based on bromobutyl rubber (BIIR), polyepichlorohydrin rubber (CO), carbon black (CB), and organically modified montmorillonite clay (NC) were prepared via melt compounding technique. Effects of NC dosage on various properties of the developed BIIR-CO nanocomposites were studied. Morphological characteristics of the BIIR-CO nanocomposite revealed a good level of clay dispersion. Scanning electron microscopy analyses of the tensile fractured surfaces of the nanocomposites revealed the existence of a good interaction between NC-CB. Hybrid microstructure development between NC and CB, clay exfoliation, and improved filler dispersion in the quaternary nanocomposite significantly contributed to the overall enhancement of properties. The addition of nanoclay increases the modulus up to 54%, tear strength up to 20%, and other physicomechanical properties of the rubber nanocomposite. However, higher nanoclay dose results in the agglomeration of clay particles predominantly. An increase in the volume fraction of nanoclay platelets depreciates the thermal degradation of the BIIR-CO nanocomposites. The tortuous path offered by NC is pivotal in the significant reduction in the water vapor transmission rate (up to 30% reduction). Contact angle measurements reveal the importance of nanoclay dispersion in subsiding the surface hydrophilic nature of the nanocomposite.
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Affiliation(s)
- S. Kumar
- Rubber Technology Centre, Indian Institute of Technology, Kharagpur-721302, India
| | - G. B. Nando
- Rubber Technology Centre, Indian Institute of Technology, Kharagpur-721302, India
| | - Sujith Nair
- CEAT Limited, Vadodara-389350, Gujarat, India
| | | | - A. Sreejesh
- CEAT Limited, Vadodara-389350, Gujarat, India
| | - S. Chattopadhyay
- Rubber Technology Centre, Indian Institute of Technology, Kharagpur-721302, India
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22
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Dey P, Naskar K, Dash B, Nair S, Unnikrishnan G, Nando GB. Selective dispersion of carbon fillers into dynamically vulcanized rubber/plastic blends: a thermodynamic approach to evaluate polymer reinforcement and conductivity enhancement. RSC Adv 2015. [DOI: 10.1039/c4ra16941g] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Phase selective and thermodynamically controlled dispersion of filler particles into the dynamically vulcanized rubber/plastic blends depicting higher abundance of carbon black in the thermoplastic phase with the progressive filler addition.
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Affiliation(s)
- Pranab Dey
- Rubber Technology Centre
- Indian Institute of Technology Kharagpur
- Kharagpur – 721302
- India
| | - Kinsuk Naskar
- Rubber Technology Centre
- Indian Institute of Technology Kharagpur
- Kharagpur – 721302
- India
| | | | | | | | - Golok B. Nando
- Rubber Technology Centre
- Indian Institute of Technology Kharagpur
- Kharagpur – 721302
- India
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23
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Dey P, Naskar K, Nando GB, Dash B, Nair S, Unnikrishnan G. Meticulous analysis and consequences of microstructure changes on melt rheology and dynamic viscoelasticity of thermoplastic vulcanizates upon reprocessing. J Appl Polym Sci 2014. [DOI: 10.1002/app.41182] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Pranab Dey
- Rubber Technology Centre; Indian Institute of Technology Kharagpur; Kharagpur India
| | - Kinsuk Naskar
- Rubber Technology Centre; Indian Institute of Technology Kharagpur; Kharagpur India
| | - Golok B. Nando
- Rubber Technology Centre; Indian Institute of Technology Kharagpur; Kharagpur India
| | | | - Sujith Nair
- CEAT Limited; Chandrapura, Halol; Panchmahal Gujarat India
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24
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Subhash R, Unnikrishnan G, Balakrishnan D, Sudheer OV, Dhar P, Sudhindran S. Gastrointestinal intramural hematoma--analysis of clinical and radiological features for early differentiation from mesenteric ischemia. Indian J Gastroenterol 2014; 33:364-8. [PMID: 24671723 DOI: 10.1007/s12664-014-0449-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 02/13/2014] [Indexed: 02/04/2023]
Abstract
INTRODUCTION Long-term anticoagulation is associated with hemorrhage at various sites. Gastrointestinal intramural bleeds and hematomas (IMH) often mimic mesenteric ischemia (MI) due to similar clinical settings and imaging features, making early differentiation difficult. AIM To compare the demography, clinical features and imaging characteristics of patients presenting with IMH with those of MI, so as to help in evolving clinical and imaging guidelines to differentiate both early in the course of the disease. METHODS All radiologically (contrast-enhanced computed tomogram [CT]) diagnosed cases of gastrointestinal IMH from the hospital database during the period between 2006 and 2012 were retrospectively analyzed. This data was compared with the clinical and imaging features of a group of surgically confirmed MI during the same period. Patients not on anticoagulation therapy at the time of presentation and those with incomplete clinical or radiological data were excluded from the study. RESULTS There were 16 patients in IMH group and 54 patients in MI group. Clinical features like overt rectal bleeding or melena, and prolonged prothrombin time-international normalized ratio (PT-INR) more than three, and CT features like proximal location in the bowel, increased bowel wall thickness, hyperdensity on plain scan (>40 Hounsfield units (HU)), and short segment bowel involvement were significantly associated with IMH. Visualization of embolus and absent mesenteric vasculature to a segment of intestine in CT was significantly associated with MI. CONCLUSION Attention to clinical features and early CT scan can aid in early differentiation of IMH from MI, facilitating appropriate intervention early in the course of disease.
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Affiliation(s)
- R Subhash
- Department of Gastrointestinal Surgery and Liver Transplantation, Amrita Institute of Medical Sciences and Research Centre, Aims Ponekkara PO, Kochi, 682 041, India,
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25
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Dey P, Naskar K, Dash B, Nair S, Unnikrishnan G, Nando GB. Thermally cross-linked and sulphur-cured soft TPVs based on S-EB-S and S-SBR blends. RSC Adv 2014. [DOI: 10.1039/c4ra04722b] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Novel thermally cross-linked and sulphur-vulcanized TPVs based on S-EB-S and S-SBR blends have registered good mechanical and dynamic mechanical properties with reduced hardness suitable for automotive applications.
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Affiliation(s)
- Pranab Dey
- Rubber Technology Centre
- Indian Institute of Technology Kharagpur
- Kharagpur – 721302, India
| | - Kinsuk Naskar
- Rubber Technology Centre
- Indian Institute of Technology Kharagpur
- Kharagpur – 721302, India
| | | | | | | | - Golok B. Nando
- Rubber Technology Centre
- Indian Institute of Technology Kharagpur
- Kharagpur – 721302, India
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26
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Priya Dasan K, Unnikrishnan G, Purushothaman E. Mechanical, Solvent Imbibing, and Dielectric Behavior of Short Nylon Fiber/Poly(ethylene-co
-vinyl acetate) Composites. Adv Polym Technol 2013. [DOI: 10.1002/adv.21374] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- K. Priya Dasan
- Material Chemistry Division; School of Advanced Sciences; VIT University; Vellore 632 014 India
| | - G. Unnikrishnan
- Polymer Science and Technology Laboratory; NITC; Calicut 673 601 India
| | - E. Purushothaman
- Department of Chemistry; University of Calicut; Calicut 673 635 India
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27
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Elanthikkal S, Francis T, Unnikrishnan G, Varghese S, Guthrie J. Barrier properties of poly(ethylene-co-vinyl acetate)/cellulose composite membranes. POLYM ENG SCI 2012. [DOI: 10.1002/pen.23172] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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28
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Sudhindran S, Aboobacker S, Menon RN, Unnikrishnan G, Sudheer OV, Dhar P. Cost and efficacy of immunosuppression using generic products following living donor liver transplantation in India. Indian J Gastroenterol 2012; 31:20-3. [PMID: 22194185 DOI: 10.1007/s12664-011-0138-0] [Citation(s) in RCA: 12] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2010] [Accepted: 09/27/2011] [Indexed: 02/04/2023]
Abstract
BACKGROUND Cost of post liver transplant immunosuppression is a major financial burden to patients in developing countries. In India, generic varieties of various immunosuppressants are often used without any definite evidence to their efficacy. This study was aimed at studying the dosage, side effect profile and cost of post-liver transplant immunosuppression using generic products in Indian population following living donor liver transplantation (LDLT). METHODS Data on dose, cost, and toxicity of immunosuppression were retrieved retrospectively from case records of 59 patients who had undergone LDLT at our center. RESULTS Adequate immunosuppression was obtained by tacrolimus (Pangraf(®)-Panacea) of 0.04 to 0.05 mg/Kg, and mycophenolate (Mycept(®)-Panacea) of 500 to 1,000 mg; the acute rejection rate was 15% during the first month. Serum tacrolimus levels were 5.4 to 7.3 ng/mL. The cost of immunosuppression varied from Rs. 28,705 in the first month to Rs. 8,820 per month at the end of first year, amounting to an average monthly cost of Rs. 17,250. Approximately 23% and 51% of cost was for mycophenolate and for drug level measurement of tacrolimus, respectively. CONCLUSION Average cost of immunosuppression after LDLT in India is much lower than that reported elsewhere in the world, since lower drug doses are needed and cheaper generic drugs are available. This can be reduced further by decreasing the frequency of tacrolimus drug level measurement.
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Affiliation(s)
- S Sudhindran
- Amrita Institute of Medical Sciences, Elamakkara PO, Kochi, 682 026 Kerala, India.
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29
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Silviya EK, Unnikrishnan G, Varghese S, Guthrie JT. Thermal and mechanical characterization of EVA/banana fiber-derived cellulose composites. J Appl Polym Sci 2011. [DOI: 10.1002/app.35140] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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30
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Rajesh C, Manoj KC, Unnikrishnan G, Purushothaman E. Dielectric Properties of Short Nylon-6 Fiber-Reinforced NBR Composites. Adv Polym Technol 2011. [DOI: 10.1002/adv.20274] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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31
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Bhadrinath N, Unnikrishnan G, Rekha V, Kumar L. 17 an evaluation of the donor profiles and outcomes of donors in living donor liver transplant (ldlt). J Clin Exp Hepatol 2011; 1:141. [PMID: 25755346 PMCID: PMC3940368 DOI: 10.1016/s0973-6883(11)60154-0] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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32
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Kalghatgi S, Vivek S, Dattaram U, Binoj S, Nitin P, Ramachandran M, Unnikrishnan G, Dinesh B, Sudheer O, Puneet D, Subhalal N, Sudhindran S. 26 bilirubin as a predictor of early mortality after liver transplantation. J Clin Exp Hepatol 2011; 1:144-5. [PMID: 25755353 PMCID: PMC3940095 DOI: 10.1016/s0973-6883(11)60163-1] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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33
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Saraf V, Suhas R, Dattaram U, Binoj S, Menon R, Dinesh B, Unnikrishnan G, Sudheer O, Sudhindran S, Dhar P, Subhalal N. 20 predictors for need for liver transplants in acute zinc phosphide poisoning. J Clin Exp Hepatol 2011; 1:142. [PMID: 25755349 PMCID: PMC3940328 DOI: 10.1016/s0973-6883(11)60157-6] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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34
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Manoj KC, Kumari P, Unnikrishnan G. Cure characteristics, swelling behaviors, and mechanical properties of carbon black filler reinforced EPDM/NBR blend system. J Appl Polym Sci 2010. [DOI: 10.1002/app.33476] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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35
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Kumari P, Radhakrishnan CK, Unnikrishnan G, Varghese S, Sujith A. Natural Rubber/Acrylonitrile Butadiene Rubber Blend Membranes: Vapor Permeation Properties. Chem Eng Technol 2010. [DOI: 10.1002/ceat.200900268] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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36
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Kumar RA, Velayudhan KT, Ramachandran V, Bhai RS, Unnikrishnan G, Vasu K. Adsorption and removal kinetics of phosphonate from water using natural adsorbents. Water Environ Res 2010; 82:62-68. [PMID: 20112539 DOI: 10.2175/106143009x447939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The removal of phosphonate from water was studied using some natural adsorbents. Potassium phosphonate is a fungicide used for the control of Phytophthora capsici, which is prevalent in black pepper (Piper nigrum L.). Batch adsorption kinetic experiments were conducted on the adsorption of phosphonate onto the adsorbents. The concentration of phosphonate was measured on a high-performance liquid chromatograph fitted with a conductivity detector. The percentage removal of phosphonate by powdered laterite stone (PLS) from water was 40.4%, within a residence time of 15 minutes. The mechanisms of the rate of adsorption were analyzed and compared using the pseudo-second-order, Elovich, and intraparticle diffusion models. The experimental data was found to correlate well with the pseudo-second-order kinetic model, indicating adsorption as a chemisorption process. A possible reaction in the phosphonate-PLS system also has been proposed. The PLS can be used as a low-cost natural adsorbent for phosphonate removal from water.
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Affiliation(s)
- R Anil Kumar
- Department of Science and Humanities, National Institute of Technology-Calicut, Kozhikode, Kerala, India.
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37
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38
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Nair TM, Kumaran MG, Unnikrishnan G, Pillai VB. Dynamic mechanical analysis of ethylene-propylene-diene monomer rubber and styrene-butadiene rubber blends. J Appl Polym Sci 2009. [DOI: 10.1002/app.29367] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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39
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Suresh KI, Tamboli JR, Rao BS, Verma S, Unnikrishnan G. Effect of core group substituents on the monomer mesophase, photocuring, and film viscoelastic properties of mesogenic diacrylates. POLYM ADVAN TECHNOL 2008. [DOI: 10.1002/pat.1141] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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40
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Priya Dasan K, Unnikrishnan G, Purushothaman E. Solvent transport through carbon black filled poly(ethylene-co-vinyl acetate) composites. EXPRESS POLYM LETT 2008. [DOI: 10.3144/expresspolymlett.2008.45] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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41
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Kumari P, Radhakrishnan CK, George S, Unnikrishnan G. Mechanical and sorption properties of poly(ethylene-co-vinyl acetate)(EVA) compatibilized acrylonitrile butadiene rubber/natural rubber blend systems. J Polym Res 2007. [DOI: 10.1007/s10965-007-9148-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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42
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Hennelly BM, Naughton TJ, McDonald J, Sheridan JT, Unnikrishnan G, Kelly DP, Javidi B. Spread-space spread-spectrum technique for secure multiplexing. Opt Lett 2007; 32:1060-2. [PMID: 17410235 DOI: 10.1364/ol.32.001060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
A novel technique for multiplexing complex images is proposed in which each image may be demultiplexed only if a set of random encryption keys is known. The technique utilizes the ability of the double random phase encoding method to spread a signals' energy in both the space and the spatial frequency domains in a controlled manner. To multiplex, images are independently encrypted with different phase keys and then superimposed by recording sequentially on the same material. Each image is extracted by using the particular key associated with it. During decryption the energy from the other images is further spread, making it possible to minimize its effects by using suitable filters. Wigner analysis is applied to the technique, and numerical results are presented.
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Affiliation(s)
- B M Hennelly
- Department of Computer Science, National University of Ireland, Ireland.
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43
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Nair TM, Kumaran MG, Unnikrishnan G, Kunchandy S. Ageing studies of ethylene propylene diene monomer rubber/styrene butadiene rubber blends: Effects of heat, ozone, gamma radiation, and water. J Appl Polym Sci 2007. [DOI: 10.1002/app.27497] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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44
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Anusree S, Sujith A, Radhakrishnan C, Unnikrishnan G. Organic vapor permeation through natural rubber/poly(ethylene-co-vinyl acetate) blend membranes. POLYM ENG SCI 2007. [DOI: 10.1002/pen.20954] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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45
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Manoj KC, Unnikrishnan G. Cure characteristics, morphology, and mechanical properties of ethylene–propylene–diene–monomer rubber/acrylonitrile butadiene rubber blends. J Appl Polym Sci 2007. [DOI: 10.1002/app.26135] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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46
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Radhakrishnan C, Alex R, Unnikrishnan G. Thermal, ozone and gamma ageing of styrene butadiene rubber and poly(ethylene-co-vinyl acetate) blends. Polym Degrad Stab 2006. [DOI: 10.1016/j.polymdegradstab.2005.06.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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47
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Habeeb Rahiman K, Unnikrishnan G. The Behaviour of Styrene Butadiene Rubber/Acrylonitrile Butadiene Rubber Blends in the Presence of Chlorinated Hydrocarbons. J Polym Res 2006. [DOI: 10.1007/s10965-005-9038-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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48
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Padmini M, Radhakrishnan CK, Sujith A, Unnikrishnan G, Purushothaman E. Molecular transport of aliphatic hydrocarbons through styrene butadiene rubber/ethylene vinyl acetate blends. J Appl Polym Sci 2006. [DOI: 10.1002/app.23366] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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49
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Sujith A, Unnikrishnan G. Molecular Sorption by Heterogeneous Natural Rubber/Poly(ethylene-co-vinyl acetate) Blend Systems. J Polym Res 2005. [DOI: 10.1007/s10965-005-9021-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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50
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Kumar RA, Velayudhan KT, Vasu K, Ramachandran V, Bhai RS, Unnikrishnan G. Interaction of potassium phosphonate fungicide in laterite soil. J Environ Sci Eng 2005; 47:276-85. [PMID: 17051913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Potassium phosphonate is a fungicide widely used to control Phytophthora fungi species in many crops all over the world. In this paper, an attempt has been made to study the interaction of potassium phosphonate with soil under varying pH and calcium level. Several reports available in literature indicate that the phosphonate in organic form adsorb strongly on almost all mineral surfaces and natural materials like soil and sediments. The present study conducted on laterite soil of Kerala using 2 mm sieved sample indicated that phosphonate obeys Freundlich adsorption isotherm. Though at lower concentrations, Langmuir model equally fits well, deviation was observed at higher concentrations. pH and calcium content of the soil had striking influence on the interaction of the chemical with the soil. The calcium source also appeared to influence the adsorption phenomenon. Since potassium phosphonate is extensively used to control Phytophthora fungi species in black pepper (Piper nigrum) plantations in India and liming is a standard practice followed as soil amendment in acid soils to increase the soil pH, this study may help to maintain good soil quality.
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Affiliation(s)
- R Anil Kumar
- Isotope Hydrology Division, Centre for Water Resources Development and Management, Kozhikode, Kerala, India
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