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Practical Holography XXXVII: Displays, Materials, and Applications 2023

作者： Wang, Hui Omidi, Parsa Diop, Mamadou Carson, Jeffrey J.L. Imaging Program Lawson Health Research Institute LondonON Canada School of Biomedical Engineering The University of Western Ontario LondonON Canada Department of Medical Biophysics The University of Western Ontario LondonON Canada Department of Surgery The University of Western Ontario LondonON Canada

ISBN: (纸本)9781510659957

In this paper, we introduce an electronic speckle pattern interferometry (ESPI) method for rapid assessment of transient deformations on an opaque object. The method records the change in speckle patterns over time, which relate to the change in phase of the reflected light. The system was capable of high-speed recordings enabled by a camera capable of double exposure and external triggering. Experiments were performed on an opaque PDMS phantom to track rapid surface movements from a piezoelectric acoustic driver located at the back of phantom. Acoustic pulses of different period and amplitude were tested. In each double exposure recording cycle, the image pair were digitally subtracted to reveal the change in the speckle pattern, which represented the change in phase of the object beam relative to the reference. We developed custom software to process the data, including an algorithm to unwrap the phase maps. Experiments revealed an ultimate sensitivity to displacements of approximately 1 nm for signals ranging in period from 50 µs to 200 µs. Future work will examine the capabilities of the system with respect to surfaces with different optical absorption and scattering characteristics. © 2023 SPIE.

关键词： Phantoms

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Design and in silico validation of a human body on a chip for toxicity assessment of drugs to prevent graft-versus-host disease 18

Design and in silico validation of a human body on a chip fo...

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18th IEEE Nanotechnology Materials and Devices Conference, NMDC 2023

作者： Lira Mario, M. Casado Fanny, L. Institute of Omic Sciences and Applied Biotechnology Pontificia Universidad Catolica Del Peru Program of Biomedical Engineering PUCP-UPCH Lima15088 Peru Institute of Omic Sciences Applied Biotechnology Pontificia Universidad Catolica Del Peru Lima15088 Peru

ISBN: (纸本)9798350335460

Toxicity assessment of novel drugs requires the development of models that provide information about the behavior of the cells and the drugs. Current cytotoxicity assays rely on data generated in vitro under static conditions, different from the conditions in the human body, where everything is dynamic and connected. Here we designed a body-on-a-chip and validated its utility to provide in silico information to better design in vitro cytotoxicity assays under dynamic conditions. We focus on cellular and structural features of the integrated main organs affected by systemic toxicity (heart, liver and kidneys), assuming passive mixer conditions for drug-blood interactions using the physicochemical characteristics of a model immuno-modulating drug such as sirolimus or rapamycin. Velocity, pressure and concentration fields were characterized to calculate the values of shear stress, vortex formation and mixing *** Relevance - Chronic diseases are highly prevalent in our society and predicted to become the main burden within the next decade. The most long-term successful treatment for most of them is transplantation of the affected organ. However, the risk of developing graft-versus-host disease is still a limitation for this therapeutic approach despite the availability of drugs to modulate the immune system to tolerate the donor's presence. Therefore, the toxicity assessment of novel immune drugs for organs of interest is a high priority. © 2023 IEEE.

关键词： Shear stress

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SCUBE2 regulates adherens junction dynamics and vascular barrier function during inflammation

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Cardiovascular Research 2024年第13期120卷 1636-1649页

作者： Lin, Yuh-Charn Chang, Ya-Jen Gau, Shiang-Shin Lo, Chun-Min Yang, Ruey-Bing Department of Physiology School of Medicine College of Medicine Taipei Medical University Taipei 110301 Taiwan Institute of Biomedical Sciences Academia Sinica 128 Academia Rd. Sec. 2 Taipei 115201 Taiwan Graduate School of Biostudies Kyoto University Kyoto 6068501 Japan Institute for Integrated Cell-Material Sciences (WPI-iCeMS) Kyoto University Kyoto 6068501 Japan Department of Biomedical Engineering National Yang Ming Chiao Tung University Taipei 112304 Taiwan Biomedical Translation Research Center Academia Sinica 99 Ln. 130 Academia Rd. Sec. 1 Taipei 115201 Taiwan Ph.D. Program in Drug Discovery and Development Industry College of Pharmacy Taipei Medical University 250 Wuxing St. Taipei 110301 Taiwan

Aims: SCUBE2 (signal peptide-CUB-epidermal growth factor-like domain-containing protein 2) is a secreted or membrane-bound protein originally identified from endothelial cells (ECs). Our previous work showed that SCUBE2 forms a complex with E-cadherin and stabilizes epithelial adherens junctions (AJs) to promote epithelial phenotypes. However, it remains unclear whether SCUBE2 also interacts with vascular endothelial (VE)-cadherin and modulates EC barrier function. In this study, we investigated whether and how SCUBE2 in ECs regulates vascular barrier maintenance. Methods and results: We showed that SCUBE2 colocalized and interacted with VE-cadherin and VE-protein tyrosine phosphatase (VE-PTP) within EC AJs. Furthermore, SCUBE2 knockdown disrupted EC AJs and increased EC permeability. Expression of EC SCUBE2 was suppressed at both mRNA and protein levels via the nuclear factor-κB signalling pathway in response to pro-inflammatory cytokines or permeability-inducing agents. In line with these findings, EC-specific deletion of Scube2 (EC-KO) in mice impaired baseline barrier function and worsened vascular leakiness of peripheral capillaries after local injection of histamine or vascular endothelial growth factor. EC-KO mice were also sensitive to pulmonary vascular hyperpermeability and leucocyte infiltration in response to acute endotoxin- or influenza virus-induced systemic inflammation. Meanwhile, EC-specific SCUBE2-overexpressing mice were protected from these effects. Molecular studies suggested that SCUBE2 acts as a scaffold molecule enabling VE-PTP to dephosphorylate VE-cadherin, which prevents VE-cadherin internalization and stabilizes EC AJs. As such, loss of SCUBE2 resulted in hyperphosphorylation of VE-cadherin at tyrosine 685, which led to its endocytosis, thus destabilizing EC AJs and reducing barrier function. All of these effects were exacerbated by inflammatory insults. Conclusion: We found that SCUBE2 contributes to vascular integrity by recruiting VE-

关键词： Adherens junctions SCUBE2 Vascular permeability VE-cadherin VE-PTP

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Co-channel Interference in GSO High Throughput Multi-beam Satellite in Indonesia: Study Link Budget and Capacity Analysis

Co-channel Interference in GSO High Throughput Multi-beam Sa...

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IEEE Asia-Pacific Conference on Geoscience, Electronics and Remote Sensing Technology (AGERS)

作者： Vi Bauty Riska Utami Heroe Wijanto Miftadi Sudjai Graduate Program of Regulation and Management of Telecommunication School of Electrical Engineering Telkom University Bandung Indonesia The University Center of Excellence for Intelligent Sensing-IoT School of Electrical Engineering Telkom University Bandung Indonesia Center of Excellence in Biomedical and Healthcare Technology School of Electrical Engineering Telkom University Bandung Indonesia

ISBN: (数字)9798331543105

ISBN: (纸本)9798331543112

Current satellite technology has developed rapidly from traditional satellites to High Throughput Satellite (HTS) because it offers the advantages of multibeam antennas and reuse frequencies. Nevertheless, intersystem interference exists. This study discusses Co-Channel Interference (CCI) in the 4-reuse color scheme on an 8-beam GSO HTS with Ku-band frequencies in Indonesia. The analysis was conducted by analyzing the link budget and capacity before and after interference on the user communication side, forward downlink, and return uplink. The results of the link budget before CCI, Carrier to Noise ratio or C/N on Beam 1 to 8 ranging from 23.34 dB to 23.50 dB. And C/N on the return uplink is 18.74 dB to 19.07 dB. Then after interference, the Carrier to Noise plus Interference Ratio or C/(N+I) on the forward downlink produces 11.96 dB to 12.15 dB. While the return uplink produces C/(N+I) of 13.91 to 14.05 dB for Beam 1 to Beam 8. Because CCI decreases signal quality, the total capacity decreases where the forward downlink before interference produces 8.99 Gbps to 4.74 Gbps. The return uplink capacity of 7.09 Gbps due to interference becomes 5.27 Gbps. The purpose of further research recommendations is to analyze CCI on other reuse color schemes with a more significant number of beams and analyze appropriate mitigation techniques.

关键词： High-temperature superconductors Satellite antennas Satellites Image color analysis Prevention and mitigation Downlink Throughput Ku-band Uplink Interchannel interference

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Cardiac Fibroblast-Mediated ECM Remodeling Regulates Maturation in an in vitro Cardiac Bundle Developmental Model

SSRN

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SSRN 2024年

作者： Jang, Yongjun Kang, Myeongjin Kang, Yong Guk Lee, Dongtak Jung, Hyo Gi Yoon, Dae Sung Kim, Jongseong Park, Yongdoo Department of Biomedical Sciences College of Medicine Korea University Seoul Korea Republic of School of Biomedical Engineering Korea University Seoul Korea Republic of Interdisciplinary Program in Precision Public Health Korea University Seoul Korea Republic of

Cardiac fibroblasts play an important role in heart homeostasis, regeneration, and disease by producing extracellular matrix (ECM) proteins and remodeling enzymes. Under normal conditions, fibroblasts exist in a quiescent state and maintain homeostasis, such as tissue structure and ECM turnover. However, if they become activated upon stimuli, such as injury, aging, or mechanical stress, which can lead to disease through excessive cell proliferation and ECM production. In addition to studying fibroblasts in disease progression, their role in cardiac maturation during development and whether the mechanism of cytokine and ECM production is similar to that observed during disease progression is unclear. In this study, we examined the functional and structural maturation of cardiac tissue by modulating fibroblast activity using an in vitro model of cardiac bundle formation. In this model, human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) and human cardiac fibroblasts (CFBs) were co-cultured in a fibrin gel and their morphology, beating characteristics, beating force, and mRNA expression profiles were analyzed. The results indicated that the cardiac bundle model matured structurally and functionally through tissue contraction and collagen deposition by fibroblasts, whereas inhibition of these ECM remodeling reduced maturation. In particular, the expression of second harmonic generation (SHG) and COL1A revealed that while activated fibroblasts induce structural maturation through sustained collagen deposition, excessive collagen accumulation can reduce functional maturation. Our data suggest that collagen type I expression by cardiac fibroblasts is essential for myocardial tissue maintenance and development through ECM remodeling. Furthermore, the regulation of collagen deposition by fibroblast activity is a crucial factor that influences cardiac development and disease progression. © 2024, The Authors. All rights reserved.

关键词： Stem cells

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Biological Tissue Analysis by Mid-infrared Photoacoustic Spectroscopy Using Piezoelectric Transducer

Biological Tissue Analysis by Mid-infrared Photoacoustic Spe...

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Pacific Rim Conference on Lasers and Electro-Optics (CLEO/Pacific Rim)

作者： Ryota Sasaki Saiko Kino Yuji Matsuura Graduate School of Biomedical Engineering Tohoku University Sendai Miyagi Japan

A piezoelectric photoacoustic spectroscopy system detecting ultrasound induced by irradiation of mid-infrared laser light is developed. A photoacoustic spectrum of human skin was obtained and an investigation to impro...

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Towards a single-use, low-cost endoscope for gastroenterological diagnostics

Towards a single-use, low-cost endoscope for gastroenterolog...

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Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Alysja Woods Chi Cong Nguyen Muhammad Saif Ul Islam Nigel H Lovell Thanh Nho Do David Tsai Graduate School of Biomedical Engineering UNSW Sydney Australia Tyree Institute of Health Engineering (IHealthE) UNSW Sydney Australia School of Electrical Engineering & Telecommunications UNSW Sydney Australia

Early diagnosis and treatment of diseases in the gastrointestinal (GI) tract including colorectal cancers (CRC) via natural orifices have led to a significant increase in patient survival rates. Most screening procedures utilize image-guided techniques via a conventional endoscope. The cost of conventional endoscopes is substantial, ranging in the tens of thousands of USD or more. This presents significant burden for developing countries, which are disproportionally affected by gastroenterological diseases. Conventional endoscopes also require sterilization between use. This increases the chance of cross-infection between patients. To address these problems, this paper introduces a soft endoscope with a disposable insertion tube that can be articulated. This prototype device is hydraulically actuated, capable of a 10 mm bend radius and 180-degree bend angle. The camera system provides 110 degrees field-of-view. The component parts of this disposable endoscope costs less than 200 *** relevance—Our low-cost, single-use endoscope eliminates the sterilization step required by conventional systems, thereby reducing the risks of infection and lowering the operating costs. There is also significant scope for our device to be used beyond the human GI track, such as screening for lung or bladder cancers. Given the compact footprint, the minimal cost of the disposable parts, the proposed platform can widen cancer screening programs with quantifiable economic benefit for many patients, particularly those in developing countries.

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A Reliable Kinematic Measurement of Upper Limb Exoskeleton for VR Therapy with Visual-inertial Sensors

A Reliable Kinematic Measurement of Upper Limb Exoskeleton f...

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IEEE/ASME (AIM) International Conference on Advanced Intelligent Mechatronics

作者： Thomas M. Kwok Tong Li Haoyong Yu Integrative Sciences and Engineering Programme NUS Graduate School National University of Singapore Singapore Dept. of Biomedical Engineering National University of Singapore Singapore

Virtual reality (VR) is a powerful technology that provides a structured and safe environment for ADL training, allowing patients to have a similar experience as real-world training. However, a limited robot sensing system is proven reliable for such training. The effectiveness of current robot sensors was limited due to inherent technical problems, such as the installation challenges of encoders and IMU’s drifting, acceleration, and magnetic issues. Thus, we propose a novel and reliable sensing system consisting of absolute rotary encoders and visual-inertial sensors for the upper-limb exoskeleton in VR therapy. Our sensing system has demonstrated angle measurement for various robot joint types, including hinge, ball, and revolute joints along the limb’s longitudinal axis. Its sensing feedback can construct virtual arms that interact with virtual objects in the VR environment. In our experiments, with Vicon as the ground truth, our visual-inertial sensors achieved root-mean-square errors smaller than 2.3491° and a strong correlation (r ≥ 0. 9640, p < 0. 001). Additionally, the experiment result of seven healthy subjects indicated that subjects had similar muscle activations, joint ROM, and joint trajectories in the VR task with our sensing system, compared with the real-world task. Thus, our proposed sensing system can potentially be used in the upper-limb exoskeleton for VR therapy.

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A Review of Deep Learning for biomedical Signals:Current Applications,Advancements,Future Prospects,Interpretation,and Challenges

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Computers, Materials & Continua 2025年第6期83卷 3753-3841页

作者： Ali Mohammad Alqudah Zahra Moussavi Biomedical Engineering Program University of ManitobaWinnipegMB R3T 2N2Canada Department of Electrical and Computer Engineering University of ManitobaWinnipegMB R3T 2N2Canada

This reviewpresents a comprehensive technical analysis of deep learning(DL)methodologies in biomedical signal processing,focusing on architectural innovations,experimental validation,and evaluation *** systematically evaluate key deep learning architectures including convolutional neural networks(CNNs),recurrent neural networks(RNNs),transformer-based models,and hybrid systems across critical tasks such as arrhythmia classification,seizure detection,and anomaly *** study dissects preprocessing techniques(e.g.,wavelet denoising,spectral normalization)and feature extraction strategies(time-frequency analysis,attention mechanisms),demonstrating their impact on model accuracy,noise robustness,and computational *** results underscore the superiority of deep learning over traditional methods,particularly in automated feature extraction,real-time processing,cross-modal generalization,and achieving up to a 15%increase in classification accuracy and enhanced noise resilience across electrocardiogram(ECG),electroencephalogram(EEG),and electromyogram(EMG)*** is rigorously benchmarked using precision,recall,F1-scores,area under the receiver operating characteristic curve(AUC-ROC),and computational complexitymetrics,providing a unified framework for comparing model *** addresses persistent challenges:synthetic data generationmitigates limited training samples,interpretability tools(e.g.,Gradient-weighted Class Activation Mapping(Grad-CAM),Shapley values)resolve model opacity,and federated learning ensures privacy-compliant *** from prior reviews,this work offers a structured taxonomy of deep learning architectures,integrates emerging paradigms like transformers and domain-specific attention mechanisms,and evaluates preprocessing pipelines for spectral-temporal *** advances the field by bridging technical advancements with clinical needs,such as scalability in real-world sett

关键词： Deep learning deep models biomedical signals physiological signals biosignals

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Multiplexed Implantable 'Barcode' Platform for Continuous Oxygen and Glucose Monitoring

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IEEE Sensors Journal 2024年

作者： Chen, Zheyuan Falohun, Tokunbo Kameoka, Jun Mcshane, Michael J. Texas A&M University Department of Biomedical Engineering College StationTX77843 United States Texas A&M University Department of Electrical and Computer Engineering College StationTX77843 United States Waseda University Graduate School of Information Production and Systems Fukuoka808-0135 Japan Texas A&M University Department of Biomedical Engineering Department of Materials Science and Engineering College StationTX77843 United States

Multianalyte biosensors have been of interest in various applications, especially in healthcare areas that target a broad range of biomarkers related to various pathological diseases. However, successful examples of such sensors generally utilize electrochemical transducers, a fact which limits their use as implants due to the presence of interferents in vivo, the difficulty of transdermal signal transduction, and the difficulty of miniaturizing the electronics into an integrated biocompatible form factor suitable for implantation. In this study, we demonstrate an attractive alternative for multiplexed sensing platform based on oxidoreductase enzymes coupled with optically distinct oxygen-sensitive metalloporphyrin phosphors which are immobilized within nanofilm-coated alginate microparticles;these are embedded in discrete compartments of a single miniature biocompatible hydrogel to achieve a 'barcode' sensor device. Continuous multiplex oxygen and glucose monitoring were demonstrated through the measurement of phosphorescence lifetime changes of the metalloporphyrin phosphors when exposed to different environmental conditions. The phosphorescence lifetime exhibited a negative correlation with increases in oxygen concentration for all compartments. In contrast, the oxygen-responsive assays maintained a constant phosphorescence lifetime and the glucose-responsive assays showed increased phosphorescence lifetime when the glucose concentration increased from 0 to 400 mg/dL. This observation confirmed the desired behavior without any apparent crosstalk between the adjacent oxygen- and glucose-responsive compartments. Furthermore, the sensors demonstrated high stability during repeated glucose challenges over 10 cycles. These findings suggest that the hydrogel barcode optical sensing platform has potential for use in various situations requiring multiplexed chemical analysis such as in continuous medical monitoring. © 2001-2012 IEEE.

关键词： Phosphorescence

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