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Chinese Physics B 2024年第4期33卷 640-648页

作者：陈登辉羊志付新宇秦申奥严岩王传奎李宗良邱帅 Shandong Key Laboratory of medical Physics and image Processing&Shandong Provincial engineering and Technical Center of Light Manipulations School of Physics and ElectronicsShandong Normal UniversityJinan 250358China

Orientation-dependent transport properties induced by anisotropic molecules are enticing in single-molecule junctions.Here,using the first-principles method,we theoretically investigate spin transport properties and photoresponse characteristics in trimesic acid magnetic single-molecule junctions with different molecular adsorption orientations and electrode contact sites.The transport calculations indicate that a single-molecule switch and a significant enhancement of spin transport and photoresponse can be achieved when the molecular adsorption orientation changes from planar geometry to upright geometry.The maximum spin polarization of current and photocurrent in upright molecular junctions exceeds 90%.Moreover,as the Ni tip electrode moves,the tunneling magnetoresistance of upright molecular junctions can be increased to 70%.The analysis of the spin-dependent PDOS elucidates that the spinterfaces between organic molecule and ferromagnetic electrodes are modulated by molecular adsorption orientation,where the molecule in upright molecular junctions yields higher spin polarization.Our theoretical work paves the way for designing spintronic devices and optoelectronic devices with anisotropic functionality base on anisotropic molecules.

关键词： molecular spintronics spin polarization tunneling magnetoresistance photocurrent single-molecule junctions

Constructing a biofunctionalized 3D-printed gelatin/sodium alginate/chitosan tri-polymer complex scaffold with improvised biological andmechanical properties for bone-tissue engineering

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Bio-Design and Manufacturing 2024年第1期7卷 57-73页

作者： Amit Kumar Singh Krishna Pramanik Amit Biswas Centre of Excellence in Tissue engineering Department of Biotechnology and Medical EngineeringNational Institute of TechnologyRourkela 769008India

Sodium alginate(SA)/chitosan(CH)polyelectrolyte scaffold is a suitable substrate for tissue-engineering application.The present study deals with further improvement in the tensile strength and biological properties of this type of scaffold to make it a potential template for bone-tissue regeneration.We experimented with adding 0%–15%(volume fraction)gelatin(GE),a protein-based biopolymer known to promote cell adhesion,proliferation,and differentiation.The resulting tri-polymer complex was used as bioink to fabricate SA/CH/GEmatrices by three-dimensional(3D)printing.Morphological studies using scanning electron microscopy revealed the microfibrous porous architecture of all the structures,which had a pore size range of 383–419μm.X-ray diffraction and Fourier-transform infrared spectroscopy analyses revealed the amorphous nature of the scaffold and the strong electrostatic interactions among the functional groups of the polymers,thereby forming polyelectrolyte complexes which were found to improve mechanical properties and structural stability.The scaffolds exhibited a desirable degradation rate,controlled swelling,and hydrophilic characteristics which are favorable for bone-tissue engineering.The tensile strength improved from(386±15)to(693±15)kPa due to the increased stiffness of SA/CH scaffolds upon addition of gelatin.The enhanced protein adsorption and in vitro bioactivity(forming an apatite layer)confirmed the ability of the SA/CH/GE scaffold to offer higher cellular adhesion and a bone-like environment to cells during the process of tissue regeneration.In vitro biological evaluation including the MTT assay,confocal microscopy analysis,and alizarin red S assay showed a significant increase in cell attachment,cell viability,and cell proliferation,which further improved biomineralization over the scaffold surface.In addition,SA/CH containing 15%gelatin designated as SA/CH/GE15 showed superior performance to the other fabricated 3D structures,demonstrating its potential for use in bone-tissue engineering.

关键词： Scaffold Biomaterial Sodium alginate Chitosan Gelatin 3D printing Tissue engineering

Enhancement of Solar PV Panel Efficiency Using Double Integral Sliding Mode MPPT Control

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Tsinghua Science and Technology 2024年第1期29卷 271-283页

作者： Immadisetty Rahul Raju Hariharan department of Electrical and Electronics engineering Saveetha School of EngineeringSaveetha Institute of Medical and Technical Sciences(SIMATS)Chennai 602105India

The extraction of maximum power from the solar panels,using the sliding mode control scheme,becomes popular for partial weather atmospheric conditions due to its effective dynamic duty cycle ratio.However,the sliding mode control scheme was sophisticated with single integral and double integral sliding mode control scheme,which offer enhanced maximum power extraction and support enhanced solar panel efficiency in partial weather conditions.The operation of the sliding mode control scheme depends on the selection of a sliding surface selection based on the atmospheric weather condition,which enables the effective sliding duty cycle ratio operation for the DC/DC boost converter.The duty cycle ratio of the sliding mode control resembles the usual dynamic behavior to achieve enhanced efficiency compared to the various maximum power point tracking(MPPT)schemes.The major limitation of the sliding mode control scheme is to achieve the steady state voltage error of the solar panel in minimum settling time duration.The single integral sliding mode control scheme achieves the expected steady state voltage error limit but fails to achieve minimum settling time duration.Hence,the single integral sliding mode control is extended to a double integral sliding mode control scheme to achieve both steady state voltage error limits within the minimum settling time duration.This double integral sliding mode control scheme allows us to obtain the higher sliding surface duty cycle ratio which acts as the input signal to the boost converter.This activates the enhanced stable and reliable system operation,and nullifies the lacuna of maximum solar panel efficiency under partial weather conditions.Hence,this paper aims to present the design and performance operation of the double integral sliding mode(DISM)MPPT control scheme.To validate the performance analysis of the proposed DISM MPPT control scheme,the MATLAB/Simulink model is designed and verified.Also,the performance analysis of the proposed DISM MPPT control scheme is compared with

关键词： maximum power point tracking(MPPT)schemes sliding mode controller(SMC) double integral sliding mode controller(DISMC) pulse width modulation(PWM) photovoltaic(PV)system

Weakly Supervised Object Localization with Background Suppression Erasing for Art Authentication and Copyright Protection

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Machine Intelligence Research 2024年第1期21卷 89-103页

作者： Chaojie Wu Mingyang Li Ying Gao Xinyan Xie Wing W.Y.Ng Ahmad Musyafa School of Computer Science and engineering South China University of TechnologyGuangzhou 511442China Guangdong Provincial Key Laboratory of Artificial Intelligence in medical image Analysis and Application Guangdong Provincial People's HospitalGuangzhou 510180China

The problem of art forgery and infringement is becoming increasingly prominent,since diverse self-media contents with all kinds of art pieces are released on the Internet every day.For art paintings,object detection and localization provide an efficient and ef-fective means of art authentication and copyright protection.However,the acquisition of a precise detector requires large amounts of ex-pensive pixel-level annotations.To alleviate this,we propose a novel weakly supervised object localization(WSOL)with background su-perposition erasing(BSE),which recognizes objects with inexpensive image-level labels.First,integrated adversarial erasing(IAE)for vanilla convolutional neural network(CNN)dropouts the most discriminative region by leveraging high-level semantic information.Second,a background suppression module(BSM)limits the activation area of the IAE to the object region through a self-guidance mechanism.Finally,in the inference phase,we utilize the refined importance map(RIM)of middle features to obtain class-agnostic loc-alization results.Extensive experiments are conducted on paintings,CUB-200-2011 and ILSVRC to validate the effectiveness of our BSE.

关键词： Weakly supervised object localization erasing method deep learning computer vision art authentication and copyright protection

Visualizing Wallerian degeneration in the corticospinal tract after sensorimotor cortex ischemia in mice

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Neural Regeneration Research 2024年第3期19卷 636-641页

作者： Jiao Mu Liufang Hao Zijue Wang Xuyang Fu Yusen Li Fei Hao Hongmei Duan Zhaoyang Yang Xiaoguang Li Beijing Key Laboratory for Biomaterials and Neural Regeneration School of Biological Science and Medical EngineeringBeihang UniversityBeijingChina department of Neurobiology School of Basic Medical SciencesCapital Medical UniversityBeijingChina

Stroke can cause Wallerian degeneration in regions outside of the brain,particularly in the corticospinal tract.To investigate the fate of major glial cells and axons within affected areas of the corticospinal tract following stroke,we induced photochemical infarction of the sensorimotor cortex leading to Wallerian degeneration along the full extent of the corticospinal tract.We first used a routine,sensitive marker of axonal injury,amyloid precursor protein,to examine Wallerian degeneration of the corticospinal tract.An antibody to amyloid precursor protein mapped exclusively to proximal axonal segments within the ischemic cortex,with no positive signal in distal parts of the corticospinal tract,at all time points.To improve visualization of Wallerian degeneration,we next utilized an orthograde virus that expresses green fluorescent protein to label the corticospinal tract and then quantitatively evaluated green fluorescent protein-expressing axons.Using this approach,we found that axonal degeneration began on day 3 post-stroke and was almost complete by 7 days after stroke.In addition,microglia mobilized and activated early,from day 7 after stroke,but did not maintain a phagocytic state over time.Meanwhile,astrocytes showed relatively delayed mobilization and a moderate response to Wallerian degeneration.Moreover,no anterograde degeneration of spinal anterior horn cells was observed in response to Wallerian degeneration of the corticospinal tract.In conclusion,our data provide evidence for dynamic,pathogenic spatiotemporal changes in major cellular components of the corticospinal tract during Wallerian degeneration.

关键词： corticospinal tract green fluorescent protein microglia spinal anterior horn cells stroke virus trace Wallerian degeneration

The advantages of multi-level omics research on stem cell-based therapies for ischemic stroke

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Neural Regeneration Research 2024年第9期19卷 1998-2003页

作者： Yiqing Wang Chuheng Chang Renzhi Wang Xiaoguang Li Xinjie Bao 4+4 Doctor medical Program Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingChina department of Neurosurgery Peking Union Medical College HospitalPeking Union Medical CollegeChinese Academy of Medical SciencesBeijingChina Beijing Key Laboratory for Biomaterials and Neural Regeneration School of Biological Science and Medical EngineeringBeihang UniversityBeijingChina department of Neurobiology School of Basic Medical SciencesCapital Medical UniversityBeijingChina

Stem cell transplantation is a potential therapeutic strategy for ischemic stroke. However, despite many years of preclinical research, the application of stem cells is still limited to the clinical trial stage. Although stem cell therapy can be highly beneficial in promoting functional recovery, the precise mechanisms of action that are responsible for this effect have yet to be fully elucidated. Omics analysis provides us with a new perspective to investigate the physiological mechanisms and multiple functions of stem cells in ischemic stroke. Transcriptomic, proteomic, and metabolomic analyses have become important tools for discovering biomarkers and analyzing molecular changes under pathological conditions. Omics analysis could help us to identify new pathways mediated by stem cells for the treatment of ischemic stroke via stem cell therapy, thereby facilitating the translation of stem cell therapies into clinical use. In this review, we summarize the pathophysiology of ischemic stroke and discuss recent progress in the development of stem cell therapies for the treatment of ischemic stroke by applying multi-level omics. We also discuss changes in RNAs, proteins, and metabolites in the cerebral tissues and body fluids under stroke conditions and following stem cell treatment, and summarize the regulatory factors that play a key role in stem cell therapy. The exploration of stem cell therapy at the molecular level will facilitate the clinical application of stem cells and provide new treatment possibilities for the complete recovery of neurological function in patients with ischemic stroke.

关键词： ischemic stroke mesenchymal stem cells metabolomics multilevel omics neural stem/progenitor cells neuroinflammation pathophysiology proteomics stem cell therapy transcriptomes

Performance and Emission Characteristics of a CRDI Diesel Engine Fuelled by SiO_(2) Nanoparticle-Waste Fat Biodiesel Blends

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 56-66页

作者： Babu Aurtherson P Dinesh Babu Munuswamy Ravikumar Jayabal Yuvarajan Devarajan department of Mechanical engineering Mahat Amma Institute of Engineering and TechnologyPudukkottaiTamil NaduIndia department of Mechanical engineering Rajalakshmi Institute of TechnologyChennaiTamil NaduIndia department of Thermal engineering Saveetha School of EngineeringSaveetha Institute of Medical and Technical SciencesChennaiTamil NaduIndia

This study investigates the use of waste fat biodiesel(WFB)from the leather industry as a substitute for diesel fuel.Specifically,it examines the diesel engine performance of WFB,a blend of WFB and diesel(B50),and different blends of WFB and silicon dioxide(SiO_(2))nanoparticles(B50SiO_(2)40,B50SiO_(2)80,and B50SiO_(2)120μg/g).The results indicate that the B50SiO_(2)120 blend increases brake thermal efficiency by 10.03%compared to pure biodiesel but falls 1.93%short of neat diesel.Furthermore,the B50SiO_(2)120 mixture reduces smoke,hydrocarbon,and carbon monoxide emissions by 31.87%,34.14%,and 43.97%respectively,compared to diesel.However,the B50SiO_(2)120 blend shows a 4.91%increase in nitrogen oxide emissions compared to diesel.

关键词： waste fat transesterification biodiesel silicon dioxide emission

Advances in extracellular vesicle-based combination therapies for spinal cord injury

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Neural Regeneration Research 2024年第2期19卷 369-374页

作者： Tingting Wang Guohao Huang Zhiheng Yi Sihan Dai Weiduan Zhuang Shaowei Guo department of Neurology The First Affiliated Hospital of Shantou University Medical CollegeShantouGuangdong ProvinceChina department of Biomedical engineering Shantou UniversityShantouGuangdong ProvinceChina

Spinal cord injury is a severe insult to the central nervous system that causes persisting neurological deficits.The currently available treatments involve surgical,medical,and rehabilitative strategies.However,none of these techniques can markedly reverse neurological deficits.Recently,extracellular vesicles from various cell sources have been applied to different models of spinal cord injury,thereby generating new cell-free therapies for the treatment of spinal cord injury.However,the use of extracellular vesicles alone is still associated with some notable shortcomings,such as their uncertainty in targeting damaged spinal cord tissues and inability to provide structural support to damaged axons.Therefore,this paper reviews the latest combined strategies for the use of extracellular vesicle-based technology for spinal cord injury,including the combination of extracellular vesicles with nanoparticles,exogenous drugs and/or biological scaffold materials,which facilitate the targeting ability of extracellular vesicles and the combinatorial effects with extracellular vesicles.We also highlight issues relating to the clinical transformation of these extracellular vesicle-based combination strategies for the treatment of spinal cord injury.

关键词： biomaterials combination therapy drug delivery exosomes extracellular vesicles functional recovery hydrogels scaffolds spinal cord injury tissue engineering

Response Evaluation Using Contrast-Enhanced Ultrasound for Unresectable Advanced Hepatocellular Carcinoma Treated With Tyrosine Kinase Inhibitors Plus Anti-PD-1 Antibody Therapy

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Falcon Optimization Algorithm-Based Energy Efficient Communication Protocol for Cluster-Based Vehicular Networks

Ultrasound in Medicine and Biology 2024年第1期50卷 142-149页

作者： Zhao C.-K. Guan X. Pu Y.-Y. Zhou B.-Y. Wang L.-F. Sun Y.-K. Yin H.-H. Xia H.-S. Wang X. Han H. Xu H.-X. department of Ultrasound Zhongshan Hospital Institute of Ultrasound in Medicine and Engineering Fudan University Shanghai China Shanghai Institute of medical Imaging Shanghai China Central Laboratory and department of medical Ultrasound Sichuan Academy of Medical Sciences Sichuan Provincial People's Hospital University of Electronic Science and Technology of China Chengdu China

Objective: The aim of the work described here was to evaluate the role of contrast-enhanced ultrasound (CEUS) in response evaluation for unresectable advanced hepatocellular carcinoma (HCC) treated with tyrosine kinase inhibitors (TKIs) plus anti-programmed cell death protein-1 (PD-1) antibody therapy. Methods: A prospective cohort of consecutive patients with HCC who received combined TKI/anti-PD-1 antibody treatment for unresectable HCC between January 2022 and October 2022 was included in this study. The patients underwent unenhanced ultrasound (US) and CEUS examinations before treatment and at follow-up. Changes in the largest diameters of the target tumor on unenhanced US and the largest diameters of the enhancing target tumors on CEUS were evaluated. Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 with unenhanced US and magnetic resonance imaging/computed tomography (MRI/CT) and modified RECIST (mRECIST) with CEUS and CEMRI/CT were used to assess treatment response. Results: A total of 24 HCC patients (23 men and 1 woman; mean age: 56.5 ± 8.5 y; Barcelona Clinic Liver Cancer stage C, 62.5%; 29 intrahepatic target tumors) were studied. Calculations of degree of necrosis in the target tumors revealed no significant differences between CEUS and CEMRI/CT (44.5 ± 36.2% vs. 45.3 ± 36.8%, p = 0.862). As for the differentiation of responders from non-responders, the agreement between RECIST version 1.1 of unenhanced US and mRECIST-CEUS was poor (κ coefficient = 0.233). Meanwhile, there was a high degree of concordance between mRECIST-CEUS and mRECIST-CEMRI/CT (κ coefficient = 0.812). Conclusion: CEUS proved to be superior to baseline US and is comparable to CEMRI/CT in defining treatment outcome for combined TKI/anti-PD-1 antibody therapy. © 2023 World Federation for Ultrasound in Medicine & Biology

关键词： Anti-angiogenic therapy Anti-PD-1 antibody Contrast-enhanced ultrasound Hepatocellular carcinoma

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Computers, Materials & Continua 2024年第3期78卷 4243-4262页

作者： Youseef Alotaibi B.Rajasekar R.Jayalakshmi Surendran Rajendran department of Software engineering College of ComputingUmm Al-Qura UniversityMakkah21955Saudi Arabia department of Electronics and Communication engineering Sathyabama Institute of Science and TechnologyChennai600119India department of Computer Science and engineering Panimalar Engineering CollegeChennai600123India department of Computer Science and engineering Saveetha School of EngineeringSaveetha Institute of Medical and Technical ScienceChennai602105India

Rapid development in Information Technology(IT)has allowed several novel application regions like large outdoor vehicular networks for Vehicle-to-Vehicle(V2V)transmission.Vehicular networks give a safe and more effective driving experience by presenting time-sensitive and location-aware data.The communication occurs directly between V2V and Base Station(BS)units such as the Road Side Unit(RSU),named as a Vehicle to Infrastructure(V2I).However,the frequent topology alterations in VANETs generate several problems with data transmission as the vehicle velocity differs with time.Therefore,the scheme of an effectual routing protocol for reliable and stable communications is significant.Current research demonstrates that clustering is an intelligent method for effectual routing in a mobile environment.Therefore,this article presents a Falcon Optimization Algorithm-based Energy Efficient Communication Protocol for Cluster-based Routing(FOA-EECPCR)technique in VANETS.The FOA-EECPCR technique intends to group the vehicles and determine the shortest route in the VANET.To accomplish this,the FOA-EECPCR technique initially clusters the vehicles using FOA with fitness functions comprising energy,distance,and trust level.For the routing process,the Sparrow Search Algorithm(SSA)is derived with a fitness function that encompasses two variables,namely,energy and distance.A series of experiments have been conducted to exhibit the enhanced performance of the FOA-EECPCR method.The experimental outcomes demonstrate the enhanced performance of the FOA-EECPCR approach over other current methods.

关键词： Vehicular networks communication protocol clustering falcon optimization algorithm routing