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Helmy AM, Lu A, Duggal I, Rodrigues KP, Maniruzzaman M. Electromagnetic drop-on-demand (DoD) technology as an innovative platform for amorphous solid dispersion production. Int J Pharm 2024; 658:124185. [PMID: 38703932 DOI: 10.1016/j.ijpharm.2024.124185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 04/25/2024] [Accepted: 04/29/2024] [Indexed: 05/06/2024]
Abstract
Production of amorphous solid dispersions (ASDs) is an effective strategy to promote the solubility and bioavailability of poorly water soluble medicinal substances. In general, ASD is manufactured using a variety of classic and modern techniques, most of which rely on either melting or solvent evaporation. This proof-of-concept study is the first ever to introduce electromagnetic drop-on-demand (DoD) technique as an alternative solvent evaporation-based method for producing ASDs. Herein 3D printing of ASDs for three drug-polymer combinations (efavirenz-Eudragit L100-55, lumefantrine-hydroxypropyl methylcellulose acetate succinate, and favipiravir-polyacrylic acid) was investigated to ascertain the reliability of this technique. Polarized light microscopy, differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), and Fourier Transform Infrared (FTIR) spectroscopy results supported the formation of ASDs for the three drugs by means of DoD 3D printing, which significantly increases the equilibrium solubility of efavirenz from 0.03 ± 0.04 µg/ml to 21.18 ± 4.20 µg/ml, and the equilibrium solubility of lumefantrine from 1.26 ± 1.60 µg/ml to 20.21 ± 6.91 µg/ml. Overall, the reported findings show how this new electromagnetic DoD technology can have a potential to become a cutting-edge 3D printing solvent-evaporation technique for on-demand and continuous manufacturing of ASDs for a variety of drugs.
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Wu L, Yan Z, Xie J, Xu Q, Li Z. Enhancing the catalytic H 2 production performance of magnetic Ni-Fe 2O 3-C catalyst in biomass steam gasification using electromagnetic induction heating. BIORESOURCE TECHNOLOGY 2024; 402:130844. [PMID: 38754560 DOI: 10.1016/j.biortech.2024.130844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 04/23/2024] [Accepted: 05/13/2024] [Indexed: 05/18/2024]
Abstract
In this study, a novel magnetic Ni-Fe2O3-C catalyst combined with electromagnetic induction heating in biomass steam gasification was proposed to enhance H2 production. Better catalytic performance for H2 production was observed with the Ni-Fe2O3-C catalyst under induction heating, resulting in an increase in H2 yield from 735.1 to 2271.2 mL/g-biomass (a 209.1 % enhancement). SEM, TGA and XRD analysis demonstrated a significant decrease in coking deposition, caking, and particle agglomeration of the Ni-Fe2O3-C catalyst under induction heating, while maintaining more active sites. Importantly, the benefits of induction heating were also applicable to different magnetic catalysts like Ni-Al2O3-C, Ni-ZrO2-C, and Ni-MgO-C. Experimental results revealed a logarithmic correlation between the increase in H2 yields due to induction heating and the magnetic saturation (Ms) of the catalysts. The Ni-Fe2O3-C catalyst, with a high Ms of 50.9 emu/g, showed the highest catalytic activity for H2 production under induction heating in this study.
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Gonzalez L, Johnson NC, Jones VC, Taylor L, Rand J, Fong Y, Kruper L. An Observational Cohort Study Comparing Positive Margin Rates Using an Electromagnetic Navigational System Versus Wire Localization in Breast Conservation Surgery. Ann Surg Oncol 2024; 31:3669-3671. [PMID: 38381208 DOI: 10.1245/s10434-024-15028-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 01/25/2024] [Indexed: 02/22/2024]
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Fakhlaei R, Babadi AA, Sun C, Ariffin NM, Khatib A, Selamat J, Xiaobo Z. Application, challenges and future prospects of recent nondestructive techniques based on the electromagnetic spectrum in food quality and safety. Food Chem 2024; 441:138402. [PMID: 38218155 DOI: 10.1016/j.foodchem.2024.138402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/26/2023] [Accepted: 01/06/2024] [Indexed: 01/15/2024]
Abstract
Safety and quality aspects of food products have always been critical issues for the food production and processing industries. Since conventional quality measurements are laborious, time-consuming, and expensive, it is vital to develop new, fast, non-invasive, cost-effective, and direct techniques to eliminate those challenges. Recently, non-destructive techniques have been applied in the food sector to improve the quality and safety of foodstuffs. The aim of this review is an effort to list non-destructive techniques (X-ray, computer tomography, ultraviolet-visible spectroscopy, hyperspectral imaging, infrared, Raman, terahertz, nuclear magnetic resonance, magnetic resonance imaging, and ultrasound imaging) based on the electromagnetic spectrum and discuss their principle and application in the food sector. This review provides an in-depth assessment of the different non-destructive techniques used for the quality and safety analysis of foodstuffs. We also discussed comprehensively about advantages, disadvantages, challenges, and opportunities for the application of each technique and recommended some solutions and developments for future trends.
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Enrique CGG, Medel-Plaza M, Correa JJA, Sarnago H, Acero J, Burdio JM, Lucía Ó, Esteban J, Gómez-Barrena E. Biofilm on total joint replacement materials can be reduced through electromagnetic induction heating using a portable device. J Orthop Surg Res 2024; 19:304. [PMID: 38769535 PMCID: PMC11103973 DOI: 10.1186/s13018-024-04785-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Accepted: 05/07/2024] [Indexed: 05/22/2024] Open
Abstract
BACKGROUND Periprosthetic joint infection is a serious complication following joint replacement. The development of bacterial biofilms bestows antibiotic resistance and restricts treatment via implant retention surgery. Electromagnetic induction heating is a novel technique for antibacterial treatment of metallic surfaces that has demonstrated in-vitro efficacy. Previous studies have always employed stationary, non-portable devices. This study aims to assess the in-vitro efficacy of induction-heating disinfection of metallic surfaces using a new Portable Disinfection System based on Induction Heating. METHODS Mature biofilms of three bacterial species: S. epidermidis ATCC 35,984, S. aureus ATCC 25,923, E. coli ATCC 25,922, were grown on 18 × 2 mm cylindrical coupons of Titanium-Aluminium-Vanadium (Ti6Al4V) or Cobalt-chromium-molybdenum (CoCrMo) alloys. Study intervention was induction-heating of the coupon surface up to 70ºC for 210s, performed using the Portable Disinfection System (PDSIH). Temperature was monitored using thermographic imaging. For each bacterial strain and each metallic alloy, experiments and controls were conducted in triplicate. Bacterial load was quantified through scraping and drop plate techniques. Data were evaluated using non-parametric Mann-Whitney U test for 2 group comparison. Statistical significance was fixed at p ≤ 0.05. RESULTS All bacterial strains showed a statistically significant reduction of CFU per surface area in both materials. Bacterial load reduction amounted to 0.507 and 0.602 Log10 CFU/mL for S. aureus on Ti6Al4V and CoCrMo respectively, 5.937 and 3.500 Log10 CFU/mL for E. coli, and 1.222 and 0.372 Log10 CFU/mL for S. epidermidis. CONCLUSIONS Electromagnetic induction heating using PDSIH is efficacious to reduce mature biofilms of S aureus, E coli and S epidermidis growing on metallic surfaces of Ti6Al4V and CoCrMo alloys.
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Vasilaki E, Markoulakis E, Lazari D, Psaroudaki A, Barbounakis I, Antonidakis E. A Novel Low-Frequency Electromagnetic Active Inertial Sensor for Drug Detection. SENSORS (BASEL, SWITZERLAND) 2024; 24:3059. [PMID: 38793913 PMCID: PMC11125059 DOI: 10.3390/s24103059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 04/30/2024] [Accepted: 05/08/2024] [Indexed: 05/26/2024]
Abstract
The purpose of this paper is to demonstrate a new discovery regarding the interaction between materials and very low radio frequencies. Specifically, we observed a feedback response on an inertia active sensor when specific frequencies (around 2-4 kHz) are used to irradiate targeted pharmaceutical samples like aspirin or paracetamol drugs. The characteristics of this phenomenon, such as excitation and relaxation time, the relation between deceleration and a material's quantity, and signal amplitude, are presented and analyzed. Although the underlying physics of this phenomenon is not yet known, we have shown that it has potential applications in remote identification of compounds, detection, and location sensing, as well as identifying substances that exist in plants without the need for any processing. This method is fast, accurate, low-cost, non-destructive, and non-invasive, making it a valuable area for further research that could yield spectacular results in the future.
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Fichtl A, Sheikhani A, Wagner M, Kleger A, Müller M, Sturm N, Walter B, Franz AM. Implementing an electromagnetic tracking navigation system improves the precision of endoscopic transgastric necrosectomy in an ex vivo model. Sci Rep 2024; 14:10055. [PMID: 38698058 PMCID: PMC11066121 DOI: 10.1038/s41598-024-60647-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 04/25/2024] [Indexed: 05/05/2024] Open
Abstract
Endoscopic transgastric necrosectomy is crucial in the management of complications resulting from necrotizing pancreatitis. However, both real-time and visual-spatial information is lacking during the procedure, thereby jeopardizing a precise positioning of the endoscope. We conducted a proof-of-concept study with the aim of overcoming these technical difficulties. For this purpose, a three-dimensional (3D) phantom of a stomach and pancreatic necroses was 3D-printed based on spatial information from individual patient CT scans and subsequently integrated into a silicone torso. An electromagnetic (EM) sensor was adjusted inside the endoscope´s working channel. A software interface enabled real time visualization. The accuracy of this novel assistant system was tested ex vivo by four experienced interventional endoscopists who were supposed to reach seven targets inside the phantom in six different experimental runs of simulated endoscopic transgastric necrosectomy. Supported by endoscopic camera view combined with real-time 3D visualization, all endoscopists reached the targets with a targeting error ranging between 2.6 and 6.5 mm in a maximum of eight minutes. In summary, the EM tracking system might increase efficacy and safety of endoscopic transgastric necrosectomy at the experimental level by enhancing visualization. Yet, a broader feasibility study and further technical improvements are mandatory before aiming at implementation into clinical setting.
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Joseph Bassey E, Cheng JH, Sun DW. Comparative elucidation of bioactive and antioxidant properties of red dragon fruit peel as affected by electromagnetic and conventional drying approaches. Food Chem 2024; 439:138118. [PMID: 38109834 DOI: 10.1016/j.foodchem.2023.138118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 11/27/2023] [Accepted: 11/28/2023] [Indexed: 12/20/2023]
Abstract
The effects of near-infrared (NIRD), mid-infrared (MIRD), far-infrared (FIRD), microwave (MWD), and hot air drying (HAD) on drying kinetic, colour, phytochemical composition, and antioxidant activity of red dragon fruit peel (RDFP) was evaluated. Results indicated that drying methods induced varying microstructural and chemical changes on RDFP, significantly influencing moisture removal rates and phytochemical retention. The lowest drying time was observed for MWD, while MIRD presented the highest drying time. FIRD drying was more favourable for retaining TPC, TFC, betacyanin and betaxanthin, while the ascorbic acid content was better retained during MIRD and NIRD. Enhancements in ABTS, CUPRAC and reducing power were associated with FIRD, and NIRD and MIRD enhanced DPPH and HRSA. Overall, chemical modifications induced by drying improved the phytochemical and antioxidant properties but presented adversative effects on ascorbic acid and DPPH. The study presented an essential background for the optimal drying of RDFP.
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Mizushima M, Kawabori M, Yamazaki K, Egawa K, Fujimura M. Ommaya reservoir placement using ultrasound guidance via anterior fontanelle combined with frameless electromagnetic neuronavigation in patients with mucopolysaccharidosis type 2: Case reports and review of the literature. Childs Nerv Syst 2024; 40:1603-1607. [PMID: 38165414 DOI: 10.1007/s00381-023-06265-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 12/20/2023] [Indexed: 01/03/2024]
Abstract
Mucopolysaccharidosis type II (MPS II) results from the genetic deficiency of a lysosomal enzyme and is associated with central nervous system (CNS) dysfunction. In Japan, in addition to intravenous enzyme administration, intracerebroventricular enzyme delivery through the Ommaya reservoir has recently gained approval. Nevertheless, the ideal approach for safely implanting the reservoir into the narrow ventricles of infantile MPS II patients remains uncertain. In this report, we present two cases of successful reservoir placement in infantile MPS II patients using ultrasound guidance via the anterior fontanelle, coupled with flameless electromagnetic neuronavigation.
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Dürrbeck C, Gomez-Sarmiento IN, Androulakis I, Sauer BC, Kolkman-Deurloo IK, Bert C, Beaulieu L. A comprehensive quality assurance protocol for electromagnetic tracking in brachytherapy. Med Phys 2024; 51:3184-3194. [PMID: 38456608 DOI: 10.1002/mp.17017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 01/31/2024] [Accepted: 02/24/2024] [Indexed: 03/09/2024] Open
Abstract
BACKGROUND Electromagnetic tracking (EMT) systems have proven to be a valuable source of information regarding the location and geometry of applicators in patients undergoing brachytherapy (BT). As an important element of an enhanced and individualized pre-treatment verification, EMT can play a pivotal role in detecting treatment errors and uncertainties to increase patient safety. PURPOSE The purpose of this study is two-fold: to design, develop and test a dedicated measurement protocol for the use of EMT-enabled afterloaders in BT and to collect and compare the data acquired from three different radiation oncology centers in different clinical environments. METHODS A novel quality assurance (QA) phantom composed of a scaffold with supports to fix the field generator, different BT applicators, and reference sensors (sensor verification tools) was used to assess the precision (jitter error) and accuracy (relative distance errors and target registration error) of the EMT sensor integrated into an afterloader prototype. Measurements were repeated in different environments where EMT measurements are likely to be performed, namely an electromagnetically clean laboratory, a BT suite, an operating room, and, if available, a CT suite and an MRI suite dedicated to BT. RESULTS The mean positional jitter was consistently under 0.1 mm across all measurement points, with a slight trend of increased jitter at greater distances from the field generator. The mean variability of sensor positioning in the tested tandem and ring gynecological applicator was also below 0.1 mm. The tracking accuracy close to the center of the measurement volume was higher than at its edges. The relative distance error at the center was 0.2-0.3 mm with maximum values reaching 1.2-1.8 mm, but up to 5.5 mm for measurement points close to the edges. In general, similar accuracy results were obtained in the clinical environments and in all investigated institutions (median distance error 0.1-0.4 mm, maximum error 1.0-2.0 mm), however, errors were found to be larger in the CT suite (median distance error up to 1.0 mm, maximum error up to 3.6 mm). CONCLUSION The presented quality assessment protocol for EMT systems in BT has demonstrated that EMT offers a high-accuracy determination of the applicator/implant geometry even in clinical environments. In addition to that, it has provided valuable insights into the performance of EMT-enabled afterloaders across different radiation oncology centers.
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Long Z, Chi Y, Zhang X, Li H, Yang D, Li D, Jiang Z. An EM-Tracked Approach for Calibrating the 3D Pose of Flexible Endoscopes. Ann Biomed Eng 2024; 52:1435-1447. [PMID: 38402316 DOI: 10.1007/s10439-024-03469-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 02/06/2024] [Indexed: 02/26/2024]
Abstract
Flexible endoscopes are ideal instruments for visualizing and diagnosing the inner surfaces of organs via a minimally invasive incision. Calibrating a flexible endoscope is a troublesome yet inevitable process in image-based tools tracking. Aiming to simplify the calibration process, we propose an electromagnetic (EM)-tracked calibration approach that does not require any predefined poses of the EM sensor. A three-stage calibration protocol was presented in an extensor. First, the orientation of the endoscope tube was derived by conducting a circular rotation of the endoscope around its axis utilizing a pair of tightly bearing stands. Second, the 3D position of the endoscope tip was acquired by having the tip come into contact with a flat plane. Third, the pose model of the bending section was derived and transformed into the local coordinate system of the EM sensor attached to the endoscope handle. To assess the accuracy of the proposed calibration approach, two experiments were designed and performed. Experimental results indicate accuracies of 0.09 ± 0.06 deg and 0.03 ± 0.19 deg in the estimation of the endoscope tube orientation and 0.52 ± 0.29, 0.33 ± 0.11, and 0.29 ± 0.17 mm in the x, y, and z estimations of the endoscope tip position, respectively. The proposed approach is accurate and easy to operate, does not require the employment of custom calibration markers, and can be used not only in surgical training systems but also in the endoscopic-based tools tracking.
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Bouisset N, Nissi J, Laakso I, Reynolds RF, Legros A. Is activation of the vestibular system by electromagnetic induction a possibility in an MRI context? Bioelectromagnetics 2024; 45:171-183. [PMID: 38348647 DOI: 10.1002/bem.22497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Revised: 11/21/2023] [Accepted: 12/16/2023] [Indexed: 04/17/2024]
Abstract
In recent years, an increasing number of studies have discussed the mechanisms of vestibular activation in strong magnetic field settings such as occur in a magnetic resonance imaging scanner environment. Amid the different hypotheses, the Lorentz force explanation currently stands out as the most plausible mechanism, as evidenced by activation of the vestibulo-ocular reflex. Other hypotheses have largely been discarded. Nonetheless, both human data and computational modeling suggest that electromagnetic induction could be a valid mechanism which may coexist alongside the Lorentz force. To further investigate the induction hypothesis, we provide, herein, a first of its kind dosimetric analysis to estimate the induced electric fields at the vestibular system and compare them with what galvanic vestibular stimulation would generate. We found that electric fields strengths from induction match galvanic vestibular stimulation strengths generating vestibular responses. This review examines the evidence in support of electromagnetic induction of vestibular responses, and whether movement-induced time-varying magnetic fields should be further considered and investigated.
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Ball JM, Li W. Using high-resolution microscopy data to generate realistic structures for electromagnetic FDTD simulations from complex biological models. Nat Protoc 2024; 19:1348-1380. [PMID: 38332306 DOI: 10.1038/s41596-023-00947-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 11/08/2023] [Indexed: 02/10/2024]
Abstract
Finite-difference time-domain (FDTD) electromagnetic simulations are a computational method that has seen much success in the study of biological optics; however, such simulations are often hindered by the difficulty of faithfully replicating complex biological microstructures in the simulation space. Recently, we designed simulations to calculate the trajectory of electromagnetic light waves through realistically reconstructed retinal photoreceptors and found that cone photoreceptor mitochondria play a substantial role in shaping incoming light. In addition to vision research and ophthalmology, such simulations are broadly applicable to studies of the interaction of electromagnetic radiation with biological tissue. Here, we present our method for discretizing complex 3D models of cellular structures for use in FDTD simulations using MEEP, the MIT Electromagnetic Equation Propagation software, including subpixel smoothing at mesh boundaries. Such models can originate from experimental imaging or be constructed by hand. We also include sample code for use in MEEP. Implementation of this algorithm in new code requires understanding of 3D mathematics and may require several weeks of effort, whereas use of our sample code requires knowledge of MEEP and C++ and may take up to a few hours to prepare a model of interest for 3D FDTD simulation. In all cases, access to a facility supercomputer with parallel processing capabilities is recommended. This protocol offers a practical solution to a significant challenge in the field of computational electrodynamics and paves the way for future advancements in the study of light interaction with biological structures.
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Flanagan W, Becraft K, Warren H, Stavrakis AI, Bernthal NM, Hardin TJ, Clites TR. Prosthetic Limb Attachment via Electromagnetic Attraction Through a Closed Skin Envelope. IEEE Trans Biomed Eng 2024; 71:1552-1564. [PMID: 38090864 DOI: 10.1109/tbme.2023.3342652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
OBJECTIVE Current socket-based methods of prosthetic limb attachment are responsible for many of the dominant problems reported by persons with amputation. In this work, we introduce a new paradigm for attachment via electromagnetic attraction between a bone-anchored ferromagnetic implant and an external electromagnet. Our objective was to develop a design framework for electromagnetic attachment, and to evaluate this framework in the context of transfemoral amputation. METHODS We first used inverse dynamics to calculate the forces required to suspend a knee-ankle-foot prosthesis during gait. We then conducted cadaveric dissections to inform implant geometry and design a surgical methodology for covering the implant. We also developed an in silico framework to investigate how electromagnet design affects system performance. Simulations were validated against benchtop testing of a custom-built electromagnet. RESULTS The physical electromagnet matched simulations, with a root-mean-square percentage error of 4.2% between measured and predicted forces. Using this electromagnet, we estimate that suspension of a prosthesis during gait would require 33 W of average power. After 200 and 1000 steps of simulated walking, the temperature at the skin would increase 2.3 °C and 15.4 °C relative to ambient, respectively. CONCLUSION Our design framework produced an implant and electromagnet that could feasibly suspend a knee-ankle-foot prosthesis during short walking bouts. Future work will focus on optimization of this system to reduce heating during longer bouts. SIGNIFICANCE This work demonstrates the initial feasibility of an electromagnetic prosthetic attachment paradigm that has the potential to increase comfort and improve residual limb health for persons with amputation.
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Olszewski J. Electrical safety assessment of a prototype device for electromagnetic stimulation of the ear in patients with tinnitus. OTOLARYNGOLOGIA POLSKA 2024; 78:50-54. [PMID: 38623855 DOI: 10.5604/01.3001.0053.9036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
<b><br>Aim:</b> The aim of the study was to evaluate the results of electrical safety results of a prototype electromagnetic ear stimulation device in patients with tinnitus.</br> <b><br>Material and methods:</b> The electrical safety tests of the prototype device for electro- and magnetostimulation of the hearing organ were carried out at the Center for Attestation and Certification Tests in Gliwice. The tests concerned selected parameters including the PN-EN standard.</br> <b><br>Results:</b> Safety studies of the prototype electrical stimulation device for the ear in patients with tinnitus were necessary to perform the planned further preclinical studies. Obtained results regarding: identification and labeling of the device; protection against electric shock; checking protective earthing, functional earthing and potential equalization; checking the leakage current and auxiliary currents of the patient; checking the distances through the solid insulation and the use of thin insulating spacers; checking the electrical strength of the device insulation; checking protection against mechanical hazards of the device; checking the risk associated with surfaces, corners and edges, and checking the protection against excessive temperatures and other threats comply with the standard PN-EN.</br> <b><br>Conclusions:</b> No risk to the patient and medical staff. Tests of protection against mechanical hazards of the device have shown that the only movable part whose contact with the patient could cause an unacceptable risk is the fan installed inside the housing.</br>.
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Khan RI, McElhinney K, Dickson A, Kileen RP, Murphy C, O'Brien DF. Image-guided orbital surgery: a preclinical validation study using a high-resolution physical model. BMJ Open Ophthalmol 2024; 9:e001568. [PMID: 38575345 PMCID: PMC11002346 DOI: 10.1136/bmjophth-2023-001568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 03/23/2024] [Indexed: 04/06/2024] Open
Abstract
OBJECTIVE Preclinical validation study to assess the feasibility and accuracy of electromagnetic image-guided systems (EM-IGS) in orbital surgery using high-fidelity physical orbital anatomy simulators. METHODS EM-IGS platform, clinical software, navigation instruments and reference system (StealthStation S8, Medtronic) were evaluated in a mock operating theatre at the Royal Victoria Eye and Ear Hospital, a tertiary academic hospital in Dublin, Ireland. Five high-resolution 3D-printed model skulls were created using CT scans of five anonymised patients with an orbital tumour that previously had a successful orbital biopsy or excision. The ability of ophthalmic surgeons to achieve satisfactory system registration in each model was assessed. Subsequently, navigational accuracy was recorded using defined anatomical landmarks as ground truth. Qualitative feedback on the system was also attained. RESULTS Three independent surgeons participated in the study, one junior trainee, one fellow and one consultant. Across models, more senior participants were able to achieve a smaller system-generated registration error in a fewer number of attempts. When assessing navigational accuracy, submillimetre accuracy was achieved for the majority of points (16 landmarks per model, per participant). Qualitative surgeon feedback suggested acceptability of the technology, although interference from mobile phones near the operative field was noted. CONCLUSION This study suggests the feasibility and accuracy of EM-IGS in a preclinical validation study for orbital surgery using patient specific 3D-printed skulls. This preclinical study provides the foundation for clinical studies to explore the safety and effectiveness of this technology.
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Trimble EJ, Stewart K, Reinersman JM. Early comparison robotic bronchoscopy versus electromagnetic navigational bronchoscopy for biopsy of pulmonary nodules in a thoracic surgery practice. J Robot Surg 2024; 18:149. [PMID: 38564059 DOI: 10.1007/s11701-024-01898-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2024] [Accepted: 03/01/2024] [Indexed: 04/04/2024]
Abstract
Pulmonary nodules are frequently encountered in high-risk patients. Often these require biopsy which can be challenging. We relate our experience comparing use of electromagnetic navigational bronchoscopy (ENB) to a robotic bronchoscopy system (RB). A retrospective review of patients undergoing bronchoscopic biopsy from 2015 to 2021. The timeframe overlapped with transition from ENB using Veran SPiN system to RB using Ion system by Intuitive. Patient and nodule characteristics were collected. Primary end point was overall diagnostic yield which was defined by pathologic confirmation of malignancy or benign finding. Secondary outcomes included diagnostic yield based on overall size of nodules and need for further work up and testing. 116 patients underwent ENB or RB of 134 nodules. No perioperative complications occurred. Diagnostic yield of ENB was 49.5% (41/91 nodules) versus 86.1% (37/43 nodules) for RB. Average nodule size for ENB was 2.55 cm versus 1.96 cm for RB. When divided based on size, ENB had a 30% diagnostic yield for nodules 1-2 cm (11/37 nodules, mean size 1.46 cm) and 64% yield for nodules 2-3 cm (14/22 nodules, mean size 2.38 cm). RB had an 81% yield for nodules 1-2 cm (mean size 1.41 cm) and 100% yield for nodules 2-3 cm (mean 2.3 cm). RB showed superiority over ENB in early implementation trials for biopsy of suspicious pulmonary nodules. It is a safe technology allowing for increased access to all lung fields and utilization in the thoracic surgical practice will be paramount to advancing the field.
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Peker F, Ferhanoğlu O. Active distance control in multi-capsule endoscopy via closed loop electromagnetic force between capsules. Med Biol Eng Comput 2024; 62:1153-1163. [PMID: 38158548 DOI: 10.1007/s11517-023-02997-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 12/09/2023] [Indexed: 01/03/2024]
Abstract
Capsule endoscopy offers a non-invasive and patient-friendly method for imaging the gastrointestinal tract, boasting superior tissue accessibility compared to traditional endoscopy and colonoscopy. While advances have led to capsules capable of drug delivery, tactile sensing, and biopsy, size constraints often limit a single capsule from having multifunctionality. In response, we introduce multi-capsule endoscopy, where individually ingested capsules, each with unique functionalities, work collaboratively. However, synchronized navigation of these capsules is essential for this approach. In this paper, we present an active distance control strategy using a closed-loop system. This entails equipping one capsule with a sphere permanent magnet and the other with a solenoid. We utilized a Simulink model, incorporating (i) the peristalsis motion on the primary capsule, (ii) a PID controller, (iii) force dynamics between capsules through magnetic dipole approximation, and (iv) position tracking of the secondary capsule. For practical implementation, Hall effect sensors determined the inter-capsule distance, and a PID controller adjusted the solenoid's current to maintain the desired capsule spacing. Our proof-of-concept experiments, conducted on phantoms and ex vivo bovine tissues, pulled the leading capsule mimicking a typical human peristalsis speed of 1 cm/min. Results showcased an inter-capsule distance of 1.94 mm ± 0.097 mm for radii of curvature at 500 mm, 250 mm, and 100 mm, aiming for a 2-mm capsule spacing. For ex vivo bovine tissue, the achieved distance was 0.97 ± 0.28 mm against a target inter-capsule distance of 1 mm. Through the successful demonstration of precise inter-capsule control, this study paves the way for the potential of multi-capsule endoscopy in future research.
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Abalymov A, Kurochkin MA, German S, Komlev A, Vavaev ES, Lyubin EV, Fedyanin AA, Gorin D, Novoselova M. Functionalization and magnetonavigation of T-lymphocytes functionalized via nanocomposite capsules targeting with electromagnetic tweezers. NANOMEDICINE : NANOTECHNOLOGY, BIOLOGY, AND MEDICINE 2024; 57:102742. [PMID: 38460654 DOI: 10.1016/j.nano.2024.102742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 02/07/2024] [Accepted: 02/23/2024] [Indexed: 03/11/2024]
Abstract
Modification of T-lymphocytes, which are capable of paracellular transmigration is a promising trend in modern personalized medicine. However, the delivery of required concentrations of functionalized T-cells to the target tissues remains a problem. We describe a novel method to functionalize T-cells with magnetic nanocapsules and target them with electromagnetic tweezers. T-cells were modified with the following magnetic capsules: Parg/DEX (150 nm), BSA/TA (300 nm), and BSA/TA (500 nm). T-cells were magnetonavigated in a phantom blood vessel capillary in cultural medium and in whole blood. The permeability of tumor tissues to captured T-cells was analyzed by magnetic delivery of modified T-cells to spheroids formed from 4T1 breast cancer cells. The dynamics of T-cell motion under a magnetic field gradient in model environments were analyzed by particle image velocimetry. The magnetic properties of the nanocomposite capsules and magnetic T-cells were measured. The obtained results are promising for biomedical applications in cancer immunotherapy.
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Rué‐Queralt J, Fluhr H, Tourbier S, Aleman‐Gómez Y, Pascucci D, Yerly J, Glomb K, Plomp G, Hagmann P. Connectome spectrum electromagnetic tomography: A method to reconstruct electrical brain source networks at high-spatial resolution. Hum Brain Mapp 2024; 45:e26638. [PMID: 38520365 PMCID: PMC10960556 DOI: 10.1002/hbm.26638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 02/01/2024] [Accepted: 02/13/2024] [Indexed: 03/25/2024] Open
Abstract
Connectome spectrum electromagnetic tomography (CSET) combines diffusion MRI-derived structural connectivity data with well-established graph signal processing tools to solve the M/EEG inverse problem. Using simulated EEG signals from fMRI responses, and two EEG datasets on visual-evoked potentials, we provide evidence supporting that (i) CSET captures realistic neurophysiological patterns with better accuracy than state-of-the-art methods, (ii) CSET can reconstruct brain responses more accurately and with more robustness to intrinsic noise in the EEG signal. These results demonstrate that CSET offers high spatio-temporal accuracy, enabling neuroscientists to extend their research beyond the current limitations of low sampling frequency in functional MRI and the poor spatial resolution of M/EEG.
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Greco A, Smith CB, Shi X, Postigo M. Single Institution Evaluation of Electromagnetic Navigation Bronchoscopy for Diagnosis of Pulmonary Lesions. J Bronchology Interv Pulmonol 2024; 31:139-145. [PMID: 38014891 DOI: 10.1097/lbr.0000000000000957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 10/17/2023] [Indexed: 11/29/2023]
Abstract
BACKGROUND Electromagnetic navigation bronchoscopy (ENB) utilizes three-dimensional reconstructions based on computed tomography to guide the biopsy of pulmonary lesions. Various limitations have been described; however, supporting data have been limited by small sample sizes. METHODS Cases of ENB for evaluation of a pulmonary lesion at a single institution during a 1-year span were reviewed for demographics, lesion location, procedural details, and final tissue diagnosis. ENB was performed by 3 pulmonologists using the Veran platform with rapid on-site evaluation. T test or Mann-Whitney U test compared continuous variables and χ 2 or Fisher exact test compared categorical variables as appropriate. A patient with a negative or inconclusive biopsy was followed for 1 year postprocedure. RESULTS A total of 107 pulmonary lesions were evaluated. The population studied had a mean age of 67 and a median pulmonary lesion size of 26.0 mm. For malignant lesions, the pathologic diagnostic yield from ENB was 52.1% (37/71). The diagnostic yield of benign lesions was much lower at 16.7% (6/36). The overall procedural complication rate was 8.4% (9/107). Complications were more likely to occur in patients with malignant lesions. The most common complication was pneumothorax, occurring in 5.6% of all biopsies and 7.0% of patients with malignant lesions. CONCLUSION This study demonstrates significant differences in diagnostic accuracy between lesions found to be malignant versus benign. Our observed complication rate was slightly higher than other groups have reported, with a greater frequency occurring in patients with malignant lesions; however, the rate of pneumothorax was still lower than computed tomography-guided transcutaneous biopsies.
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Liu Y, Zhao X, Liu Z, Sun B, Liu X, Zhao R, Liu B, Sun Z, Men Y, Hu W, Shao ZB. Functionalized lignin nanoparticles assembled with MXene reinforced polypropylene with favorable UV-aging resistance, electromagnetic shielding effects and superior fire-safety. Int J Biol Macromol 2024; 265:130957. [PMID: 38499121 DOI: 10.1016/j.ijbiomac.2024.130957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 12/23/2023] [Accepted: 03/15/2024] [Indexed: 03/20/2024]
Abstract
Deterioration in mechanical performances and aging resistance due to the introduction of flame retardants is a major obstacle for bio-based fire-safety polypropylene (PP). Herein, we reported a kind of functionalized lignin nanoparticles assembled with MXene (MX@LNP), and applied it to construct the flame-retardant PP composites (PP-MA) with superior fire safety, excellent mechanical performance, electromagnetic shielding effects and aging resistance. Specifically, the PP-MA doped with only 18 wt% flame-retardant additives (PP-MA18) achieved the UL-94 V-0 rating. In comparison to pure PP, PP-MA18 presented a greatly decreased peak of heat release rate (pHRR), total heat rate (THR), and peak smoke production rate (pSPR) by 79.7 %, 69.0 % and 75.8 %, respectively, and satisfactory decrease in total flammable and toxic volatiles evolved. The formed fine solid microstructure of carbon residuals effectively promoted the compactness of char layers. More importantly, the nano-effect and the strong interface interaction between the complexed MX@LNP and PP enhanced the tensile strength (45.78 MPa) and elongation at break (725.95 %) of PP-MA. Additionally, the significant ultraviolet absorption and electromagnetic wave dissipation performance of MXene and lignin enabled excellent aging resistance and electromagnetic shielding effects of PP-MA compared with PP. This achieved MX@LNP afforded a novel approach for developing flame retardant materials with excellent application performance.
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Zolotukhin DB, Horkowitz A, Keidar M. Electromagnetic Nature of Distant Interaction of the Atmospheric Pressure Helium Plasma Discharge Tube with Glioblastoma Cancer Cells. ACS APPLIED MATERIALS & INTERFACES 2024; 16:13597-13610. [PMID: 38453642 DOI: 10.1021/acsami.4c00619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/09/2024]
Abstract
Atmospheric pressure coaxial gaseous discharge tubes (DTs) with helium have demonstrated potential for in vitro inactivation or sensitization of glioblastoma cancer cells. Here, we study the effect of two configurations of the DT electrode system on its electromagnetic emissivity as well as other physical factors (heating and UV emission) that form in the vicinity of this device. We demonstrate that the configuration of the DT electrodes that concentrates the discharge streamers near the top of the device has a distant (cm scale) deactivation effect on U87-MG glioblastoma cancer cells when irradiated, without measurable UV components in the DT optical emission spectra. This effect persists even through different barriers such as glass, plastic, or quartz Petri dishes but is eliminated when glass or plastic dishes are filled with water. These findings demonstrate the potential for development of noninvasive, physical-based treatment methods of deep-tissue tumors.
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Dai J, Xia X, Zhang D, He S, Wan D, Chen F, Zi Y. High-performance self-desalination powered by triboelectric-electromagnetic hybrid nanogenerator. WATER RESEARCH 2024; 252:121185. [PMID: 38295459 DOI: 10.1016/j.watres.2024.121185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 01/10/2024] [Accepted: 01/23/2024] [Indexed: 02/02/2024]
Abstract
Freshwater is an essential resource in today's world, and how to produce freshwater with low or even zero power consumption is a major challenge. Here, a desalination system powered by a triboelectric-electromagnetic hybrid nanogenerator (TEHG) is presented, which can utilize the water's own energy to remove the salt ions from itself, demonstrating a new concept of "self-desalination". At a relatively low rotation speed of 150 rpm, the system can dilute NaCl brine from 4000 ppm to 145 ppm with a high salt removal rate of 147.1 μg cm-2 min-1 and a freshwater productivity of up to 31.1 L m-2 h-1. The actual seawater can also be treated with a total ion removal efficiency of 99.6 % and a freshwater productivity of 2.7 L m-2 h-1, which is superior to other renewable-energy-powered desalination systems. More importantly, fully self-powered desalination process can be realized by manual cranking and hydrokinetic energy impact, both of which are capable of treating 1000 ppm salt feed to the drinking water level. The TEHG-powered desalination system not only provides excellent desalination performance but also addresses the challenges of power consumption and limited capacity, which offers a completely new paradigm of "self-desalination".
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Porat A, Tekinalp A, Bhosale Y, Gazzola M, Meroz Y. On the mechanical origins of waving, coiling and skewing in Arabidopsis thaliana roots. Proc Natl Acad Sci U S A 2024; 121:e2312761121. [PMID: 38446852 PMCID: PMC10945788 DOI: 10.1073/pnas.2312761121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 12/07/2023] [Indexed: 03/08/2024] Open
Abstract
By masterfully balancing directed growth and passive mechanics, plant roots are remarkably capable of navigating complex heterogeneous environments to find resources. Here, we present a theoretical and numerical framework which allows us to interrogate and simulate the mechanical impact of solid interfaces on the growth pattern of plant organs. We focus on the well-known waving, coiling, and skewing patterns exhibited by roots of Arabidopsis thaliana when grown on inclined surfaces, serving as a minimal model of the intricate interplay with solid substrates. By modeling growing slender organs as Cosserat rods that mechanically interact with the environment, our simulations verify hypotheses of waving and coiling arising from the combination of active gravitropism and passive root-plane responses. Skewing is instead related to intrinsic twist due to cell file rotation. Numerical investigations are outfitted with an analytical framework that consistently relates transitions between straight, waving, coiling, and skewing patterns with substrate tilt angle. Simulations are found to corroborate theory and recapitulate a host of reported experimental observations, thus providing a systematic approach for studying in silico plant organs behavior in relation to their environment.
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