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Microbial community structure and functional metabolic diversity are associated with organic carbon availability in an agricultural soil 被引量:6
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作者 LI Juan LI Yan-ting +3 位作者 YANG Xiang-dong ZHANG Jian-jun LIN Zhi-an ZHAO Bing-qiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第12期2500-2511,共12页
Exploration of soil environmental characteristics governing soil microbial community structure and activity may improve our understanding of biogeochemical processes and soil quality. The impact of soil environmental ... Exploration of soil environmental characteristics governing soil microbial community structure and activity may improve our understanding of biogeochemical processes and soil quality. The impact of soil environmental characteristics especially organic carbon availability after 15-yr different organic and inorganic fertilizer inputs on soil bacterial community structure and functional metabolic diversity of soil microbial communities were evaluated in a 15-yr fertilizer experiment in Changping County, Beijing, China. The experiment was a wheat-maize rotation system which was established in 1991 including four different fertilizer treatments. These treatments included: a non-amended control(CK), a commonly used application rate of inorganic fertilizer treatment(NPK); a commonly used application rate of inorganic fertilizer with swine manure incorporated treatment(NPKM), and a commonly used application rate of inorganic fertilizer with maize straw incorporated treatment(NPKS). Denaturing gradient gel electrophoresis(DGGE) of the 16 S r RNA gene was used to determine the bacterial community structure and single carbon source utilization profiles were determined to characterize the microbial community functional metabolic diversity of different fertilizer treatments using Biolog Eco plates. The results indicated that long-term fertilized treatments significantly increased soil bacterial community structure compared to CK. The use of inorganic fertilizer with organic amendments incorporated for long term(NPKM, NPKS) significantly promoted soil bacterial structure than the application of inorganic fertilizer only(NPK), and NPKM treatment was the most important driver for increases in the soil microbial community richness(S) and structural diversity(H). Overall utilization of carbon sources by soil microbial communities(average well color development, AWCD) and microbial substrate utilization diversity and evenness indices(H' and E) indicated that long-term inorganic fertilizer with organic amendments incorporated(NPKM, NPKS) could significantly stimulate soil microbial metabolic activity and functional diversity relative to CK, while no differences of them were found between NPKS and NPK treatments. Principal component analysis(PCA) based on carbon source utilization profiles also showed significant separation of soil microbial community under long-term fertilization regimes and NPKM treatment was significantly separated from the other three treatments primarily according to the higher microbial utilization of carbohydrates, carboxylic acids, polymers, phenolic compounds, and amino acid, while higher utilization of amines/amides differed soil microbial community in NPKS treatment from those in the other three treatments. Redundancy analysis(RDA) indicated that soil organic carbon(SOC) availability, especially soil microbial biomass carbon(Cmic) and Cmic/SOC ratio are the key factors of soil environmental characteristics contributing to the increase of both soil microbial community structure and functional metabolic diversity in the long-term fertilization trial. Our results showed that long-term inorganic fertilizer and swine manure application could significantly improve soil bacterial community structure and soil microbial metabolic activity through the increases in SOC availability, which could provide insights into the sustainable management of China's soil resource. 展开更多
关键词 long-term fertilization regimes organic amendment soil microbial community structure microbial functional metabolic activity carbon substrate utilization
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Altered intrinsic functional connectivity of the primary visual cortex in youth patients with comitant exotropia: a resting state fMRI study 被引量:14
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作者 Pei-Wen Zhu Xin Huang +5 位作者 Lei Ye Nan Jiang Yu-Lin Zhong Qing Yuan Fu-Qing Zhou Yi Shao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第4期668-673,共6页
AIM: To evaluate the differences in the functional connectivity(FC) of the primary visual cortex(V1) between the youth comitant exotropia(CE) patients and health subjects using resting functional magnetic reson... AIM: To evaluate the differences in the functional connectivity(FC) of the primary visual cortex(V1) between the youth comitant exotropia(CE) patients and health subjects using resting functional magnetic resonance imaging(f MRI) data.METHODS: Totally, 32 CEs(25 males and 7 females) and 32 healthy control subjects(HCs)(25 males and 7 females) were enrolled in the study and underwent the MRI scanning. Two-sample t-test was used to examine differences in FC maps between the CE patients and HCs. RESULTS: The CE patients showed significantly less FC between the left brodmann area(BA17) and left lingual gyrus/cerebellum posterior lobe, right middle occipital gyrus, left precentral gyrus/postcentral gyrus and right inferior parietal lobule/postcentral gyrus. Meanwhile, CE patients showed significantly less FC between right BA17 and right middle occipital gyrus(BA19, 37).CONCLUSION: Our findings show that CE involves abnormal FC in primary visual cortex in many regions, which may underlie the pathologic mechanism of impaired fusion and stereoscopic vision in CEs. 展开更多
关键词 comitant exotropia functional connectivity primary visual cortex spontaneous activity
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Evidence of cortical reorganization of language networks after stroke with subacute Broca's aphasia:a blood oxygenation level dependent-functional magnetic resonance imaging study 被引量:8
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作者 Wei-hong Qiu Hui-xiang Wu +7 位作者 Qing-lu Yang Zhuang Kang Zhao-cong Chen Kui Li Guo-rong Qiu Chun-qing Xie Gui-fang Wan Shao-qiong Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第1期109-117,共9页
Aphasia is an acquired language disorder that is a common consequence of stroke.The pathogenesis of the disease is not fully understood,and as a result,current treatment options are not satisfactory.Here,we used blood... Aphasia is an acquired language disorder that is a common consequence of stroke.The pathogenesis of the disease is not fully understood,and as a result,current treatment options are not satisfactory.Here,we used blood oxygenation level-dependent functional magnetic resonance imaging to evaluate the activation of bilateral cortices in patients with Broca's aphasia 1 to 3 months after stroke.Our results showed that language expression was associated with multiple brain regions in which the right hemisphere participated in the generation of language.The activation areas in the left hemisphere of aphasia patients were significantly smaller compared with those in healthy adults.The activation frequency,volumes,and intensity in the regions related to language,such as the left inferior frontal gyrus(Broca's area),the left superior temporal gyrus,and the right inferior frontal gyrus(the mirror region of Broca's area),were lower in patients compared with healthy adults.In contrast,activation in the right superior temporal gyrus,the bilateral superior parietal lobule,and the left inferior temporal gyrus was stronger in patients compared with healthy controls.These results suggest that the right inferior frontal gyrus plays a role in the recovery of language function in the subacute stage of stroke-related aphasia by increasing the engagement of related brain areas. 展开更多
关键词 nerve regeneration functional magnetic resonance imaging cortical functional connectivity language regions neuroplasticity Perisylvian language regions brain activation right hemisphere picture-naming task neural regeneration
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Botulinum toxin type A plus rehabilitative training for improving the motor function of the upper limbs and activities of daily life in patients with stroke and brain injury 被引量:1
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作者 Fei Guo Wei Yue +2 位作者 Li Ren Yumiao Zhang Jing Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第9期859-861,共3页
BACKGROUND:Botulinum toxin type A(BTX-A)is mostly to be used to treat various diseases of motor disorders,whereas its effect on muscle spasm after stroke and brain injury needs further observation.OBJECTIVE:To observe... BACKGROUND:Botulinum toxin type A(BTX-A)is mostly to be used to treat various diseases of motor disorders,whereas its effect on muscle spasm after stroke and brain injury needs further observation.OBJECTIVE:To observe the effect of BTX-A plus rehabilitative training on treating muscle spasm after stroke and brain injury.DESIGN:A randomized controlled observation.SETTINGS:Department of Rehabilitation,Department of Neurology and Department of Neurosurgery,the Second Hospital of Hebei Medical University.PARTICIPANTS:Sixty inpatients with brain injury and stroke were selected from the Department of Rehabilitation,Department of Neurology and Department of Neurosurgery,the Second Hospital of Hebei Medical University from January 2001 to August 2006.They were all confirmed by CT and MRI,and had obvious increase of spastic muscle strength in upper limbs,their Ashworth grades were grade 2 or above.The patients were randomly divided into treatment group(n=30)and control group(n=30).METHODS:①Patients in the treatment group undertook comprehensive rehabilitative trainings,and they were administrated with domestic BTX-A,which was provided by Lanzhou Institute of Biological Products,Ministry of Health(S10970037),and the muscles of flexion spasm were selected for upper limbs,20-25 IU for each site.②Patients in the treatment group were assessed before injection and at 1 and 2 weeks,1 and 3 months after injection respectively,and those in the control group were assessed at corresponding time points.The recovery of muscle spasm was assessed by modified Ashworth scale(MAS,grade 0-Ⅳ;Grade 0 for without increase of muscle strength;GradeⅣfor rigidity at passive flexion and extension);The recovery of motor function of the upper limbs was evaluated with Fugl-Meyer Assessment(FMA,total score was 226 points,including 100 for exercise,14 for balance,24 for sense,44 for joint motion,44 for pain and 66 for upper limb);The ADL were evaluated with Barthel index,the total score was 100 points,60 for mild dysfunction,60-41 for moderate dysfunction,<40 for severe dysfunction).MAIN OUTCOME MEASURES:Changes of MAS grade,FMA scores and Barthel index before and after BTX-A injection.RESULTS:All the 60 patients with brain injury and stroke were involved in the analysis of results.①FMA scores of upper limbs:The FMA score in the treatment group at 2 weeks after treatment was higher than that before treatment[(14.98±10.14),(13.10±9.28)points,P<0.05],whereas there was no significant difference at corresponding time point in the control group.The FMA scores at 1 and 3 months in the treatment group[(23.36±10.69),(35.36±11.36)points]were higher than those in the control group[(20.55±10.22),(30.33±10.96)points,P<0.01].②MAS grades of upper limbs:There were obviously fewer cases of gradeⅢin MAS at 2 weeks after treatment than before treatment in the treatment group(0,9 cases,P<0.05),whereas there was no obvious difference in the control group.There were obviously fewer cases of gradeⅢin MAS at 2 weeks and 1 month after treatment in the treatment group(0,0 case)than the control group(5,2 cases,P<0.01).③Barthel index of upper limbs:The Barthel index at 2 weeks after treatment was higher than that before treatment in the treatment group[(30.36±22.25),(28.22±26.21)points,P<0.05],whereas there was no significant difference in the control group.The Barthel indexes at 1 and 3 months after treatment in the treatment group were obviously higher than those in the control group[(20.55±10.22),(30.33±10.96)points,P<0.01].CONCLUSION:BTX-A has obvious efficacy on decreasing muscle tension after stroke and brain injury,and relieving muscle spasm;Meanwhile,the combination with rehabilitative training can effectively ameliorate the motor function of upper limbs and ADL of the patients. 展开更多
关键词 Botulinum toxin type A plus rehabilitative training for improving the motor function of the upper limbs and activities of daily life in patients with stroke and brain injury TYPE
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Effect of Preparation Process of Functional Polymer Active Materials on Properties of Gadolinium Ion Selective Electrode
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作者 车吉泰 闫美兰 +1 位作者 林安 张万喜 《Journal of Rare Earths》 SCIE EI CAS CSCD 1991年第3期226-227,共2页
Recently we have studied the rare earth ion-selective electrodes with active materials of the func-tional polymers and found that the process chosen for the functional polymers had an effect on the propertiesof gadoli... Recently we have studied the rare earth ion-selective electrodes with active materials of the func-tional polymers and found that the process chosen for the functional polymers had an effect on the propertiesof gadolinium ion selective electrode besides the effects of their structures.1.Effect of preparation process of the grafted polymers on the properties ofgadolinium ion selective electrodesThe electrode membranes which consist of functional polymers as active materials were prepared by re-action of gadolinium chloride with the radiation grafted clmer of acrlic acid and polystyrene of which 展开更多
关键词 functional polymer active materials Gadolinium ion selective electrode Grafted polymers
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EFFECT OF STRUCTURE OF FUNCTIONAL POLYMER ACTIVE MATERIALS ON PROPERTIES OF GADOLINIUM ION SELECTIVE ELECTRODE
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作者 车吉泰 闫美兰 张万喜 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第3期189-193,共5页
In this paper,the functional polymeric active materials were prepared by the grafting copolymerization and their structure and properties were studied.The results show that the structure and properties of these ac- ti... In this paper,the functional polymeric active materials were prepared by the grafting copolymerization and their structure and properties were studied.The results show that the structure and properties of these ac- tive materials have the relative large effects on the properties of gadolinium ion selective electrodes. 展开更多
关键词 HDPE EFFECT OF STRUCTURE OF functional POLYMER ACTIVE MATERIALS ON PROPERTIES OF GADOLINIUM ION SELECTIVE ELECTRODE
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Characterization and Functionalisation of Activated Carbon for the Enhancement of Enzyme Catalyst Activity
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作者 Nassereldeen A Kabbashi Yara Hunud Abia Kadouf +3 位作者 Ibrahim Adebayo Bello Elwathig M.Saeed Lubna Mohamed Musa Nassereldeen Ahmed Kabbashi 《材料科学与工程(中英文B版)》 2021年第2期81-87,共7页
Background and objective:Activated carbon is commonly used as an immobilisation matrix due to its large surface area,making it a highly desirable matrix for use in immobilising enzymes as preparation for use on the in... Background and objective:Activated carbon is commonly used as an immobilisation matrix due to its large surface area,making it a highly desirable matrix for use in immobilising enzymes as preparation for use on the industrial scale.The objective of this research is to determine the effectiveness of different acids for functionalisation on immobilisation capacity and also to characterize the functionalized activated carbon for the functional groups present.Materials and methods:Activated carbon was functionalised with three acids(hydrochloric acid,nitric acid and sulphuric acid)along with a control sample washed with distilled water.Immobilisation capacity was calculated with hydrochloric acid functionalized activated carbon(HCl-FAC)giving the highest immobilization capacity(6.022 U/g).Characterisation of the functionalised activated carbon was conducted using FT-IR(Fourier Transform Infra-Red)spectroscopy analysis of the samples with the aim of analyzing the various functional groups present to determine the sample with distinct characteristics thus telling the degree of adsorption of lipase onto the activated carbon powder.Results:HNO3-FAC(functionalized activated carbon)showed a very distinct pattern as a larger number of surface functional groups emerged.The immobilisation on a matrix ensures thermal stability and increased reusability of the enzyme.Therefore,in this research,lipase sourced from Candida antarctica was immobilised on acid functionalised activated carbon.The best acid for functionalisation was found to be hydrochloric acid.Conclusion:Due to the very distinct patterns shown by the FT-IR spectrum of the HNO3-FAC after a fair comparison with others,it allows for a larger number of surface functional groups which will definitely enhance the stability of the enzyme lipase. 展开更多
关键词 Activated carbon CHARACTERIZATION functionalized activated carbon enzyme activity
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FUNCTIONALIZED CYCLODEXSTRINS BEARING AM INOALKYLIMINO GROUPS AS ACTIVE CENTERS TO CATALYZE ALDOL CONDENSATIONS
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作者 De Qi YUAN Ru Gang XIE Hua Ming ZHAO 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第8期617-620,共4页
Efficient catalysis of functinnatized β-cyctodextrins bearing aninoatkytimino groups for atdot condensations of nitrobenzatdehydes and acetone has been effected and substantiated by preparative experiments
关键词 NBA functionalIZED CYCLODEXSTRINS BEARING AM INOALKYLIMINO GROUPS AS ACTIVE CENTERS TO CATALYZE ALDOL CONDENSATIONS AS AM
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Functional magnetic resonance imaging evidence for activated functional brain areas following acupoint needling in the extremities
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《Neural Regeneration Research》 SCIE CAS CSCD 2012年第3期223-223,共1页
Totally three articles focusing on functional magnetic resonance imaging features of brain function in the activated brain regions of stroke patients undergoing acupuncture on the healthy limbs and healthy controls un... Totally three articles focusing on functional magnetic resonance imaging features of brain function in the activated brain regions of stroke patients undergoing acupuncture on the healthy limbs and healthy controls undergoing acupuncture on the lower extremities are published in three issues. We hope that our readers find these papers useful to their research. 展开更多
关键词 functional magnetic resonance imaging evidence for activated functional brain areas following acupoint needling in the extremities
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Theoretical Study on the C-H Activation in Decarbonylation of Acetaldehyde by NiL_2(L=SO_3CH_3) Using Density Functional Theory
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作者 刘红飞 JIA Tiekun MIN Xinmin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第6期1170-1172,共3页
Density functional theory calculations were carried out to explore the potential energy surface(PES) associated with the gas-phase reaction of Ni L2(L=SO3CH3) with acetone. The geometries and energies of the react... Density functional theory calculations were carried out to explore the potential energy surface(PES) associated with the gas-phase reaction of Ni L2(L=SO3CH3) with acetone. The geometries and energies of the reactants, intermediates, products and transition states of the triplet ground potential energy surfaces of [Ni, O, C2, H4] were obtained at the B3LYP/6-311++G(d,p) levels in C,H,O atoms and B3LYP/ Lanl2 dz in Ni atom. It was found through our calculations that the decabonylation of acetaldehyde contains four steps including encounter complexation, C-C activation, aldehyde H-shift and nonreactive dissociation. The results revealed that C-C activation induced by Ni L2(L=SO3CH3) led to the decarbonylation of acetaldehyde. 展开更多
关键词 density functional theory decarbonylation transition state energy C-C activation
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What Information Gap Activities can Teach Us in TESOL
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作者 Ling Zhang 《Sino-US English Teaching》 2004年第4期66-72,共7页
Starting from presenting and analyzing some information gap activities during the previous teaching experience, this article has inferred the major roles of information gap activities. Some strategies to implement the... Starting from presenting and analyzing some information gap activities during the previous teaching experience, this article has inferred the major roles of information gap activities. Some strategies to implement the information gap activities are also recommended together with the functions of the instructors via these activities. What information gap activities can teach us in TESOL (teaching English for speakers of other languages) is that information gap activities contribute to setting up a climate of a mutual autonomous learning style both for the learners and the instructors, and these activities activate a diversity in the learning atmosphere. 展开更多
关键词 information gap activities roles strategies functions mutual autonomous learning style
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DnCNN-RM:an adaptive SAR image denoising algorithm based on residual networks
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作者 OU Hai-ning LI Chang-di +3 位作者 ZENG Rui-bin WU Yan-feng LIU Jia-ning CHENG Peng 《中国光学(中英文)》 北大核心 2025年第5期1209-1218,共10页
In the field of image processing,the analysis of Synthetic Aperture Radar(SAR)images is crucial due to its broad range of applications.However,SAR images are often affected by coherent speckle noise,which significantl... In the field of image processing,the analysis of Synthetic Aperture Radar(SAR)images is crucial due to its broad range of applications.However,SAR images are often affected by coherent speckle noise,which significantly degrades image quality.Traditional denoising methods,typically based on filter techniques,often face challenges related to inefficiency and limited adaptability.To address these limitations,this study proposes a novel SAR image denoising algorithm based on an enhanced residual network architecture,with the objective of enhancing the utility of SAR imagery in complex electromagnetic environments.The proposed algorithm integrates residual network modules,which directly process the noisy input images to generate denoised outputs.This approach not only reduces computational complexity but also mitigates the difficulties associated with model training.By combining the Transformer module with the residual block,the algorithm enhances the network's ability to extract global features,offering superior feature extraction capabilities compared to CNN-based residual modules.Additionally,the algorithm employs the adaptive activation function Meta-ACON,which dynamically adjusts the activation patterns of neurons,thereby improving the network's feature extraction efficiency.The effectiveness of the proposed denoising method is empirically validated using real SAR images from the RSOD dataset.The proposed algorithm exhibits remarkable performance in terms of EPI,SSIM,and ENL,while achieving a substantial enhancement in PSNR when compared to traditional and deep learning-based algorithms.The PSNR performance is enhanced by over twofold.Moreover,the evaluation of the MSTAR SAR dataset substantiates the algorithm's robustness and applicability in SAR denoising tasks,with a PSNR of 25.2021 being attained.These findings underscore the efficacy of the proposed algorithm in mitigating speckle noise while preserving critical features in SAR imagery,thereby enhancing its quality and usability in practical scenarios. 展开更多
关键词 SAR images image denoising residual networks adaptive activation function
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A Scoping Review on the Application of FAS in Postoperative Active Pain Management Among Surgical Patients in China
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作者 Yuying Hu Yingge Tong +4 位作者 Huiqing Jin Wenqian Cheng Mengyu Xin Ke Ni Xiang Pan 《Journal of Clinical and Nursing Research》 2025年第10期199-208,共10页
Objective:To conduct a scoping review on the application status of the Functional Activity Score(FAS)in postoperative active pain management in China,providing a reference for its standardized and normative promotion.... Objective:To conduct a scoping review on the application status of the Functional Activity Score(FAS)in postoperative active pain management in China,providing a reference for its standardized and normative promotion.Methods:Computerized searches of Chinese and English databases were performed to collect studies published by Chinese scholars from 2005 to July 2025 on the application of FAS in postoperative active pain management.After strict screening,the basic characteristics,application fields,assessment models,evaluation timing,types of functional activities,and clinical outcomes of the included literature were systematically analyzed.Results:A total of 18 studies were included,involving surgical types such as thoracic surgery,general surgery,and orthopedics.All studies adopted FAS combined with the Numeric Rating Scale(NRS)for assessment,with evaluation timing mostly concentrated within 72 hours postoperatively.The selected functional activities primarily included respiration-related and limb movements.Evaluation indicators covered pain control,functional recovery,complications,adverse events,patient experience,and tool assessment,with most studies reporting positive outcomes.Conclusion:FAS can effectively enhance pain control and promote functional recovery in postoperative active pain management in China,demonstrating high clinical value.However,existing studies exhibit inconsistencies in assessment criteria,selection of activity types,and research quality. 展开更多
关键词 Activity pain functional activity score Pain management Scoping review Surgical nursing
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Med-ReLU: A Parameter-Free Hybrid Activation Function for Deep Artificial Neural Network Used in Medical Image Segmentation
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作者 Nawaf Waqas Muhammad Islam +3 位作者 Muhammad Yahya Shabana Habib Mohammed Aloraini Sheroz Khan 《Computers, Materials & Continua》 2025年第8期3029-3051,共23页
Deep learning(DL),derived from the domain of Artificial Neural Networks(ANN),forms one of the most essential components of modern deep learning algorithms.DL segmentation models rely on layer-by-layer convolution-base... Deep learning(DL),derived from the domain of Artificial Neural Networks(ANN),forms one of the most essential components of modern deep learning algorithms.DL segmentation models rely on layer-by-layer convolution-based feature representation,guided by forward and backward propagation.Acritical aspect of this process is the selection of an appropriate activation function(AF)to ensure robustmodel learning.However,existing activation functions often fail to effectively address the vanishing gradient problem or are complicated by the need for manual parameter tuning.Most current research on activation function design focuses on classification tasks using natural image datasets such asMNIST,CIFAR-10,and CIFAR-100.To address this gap,this study proposesMed-ReLU,a novel activation function specifically designed for medical image segmentation.Med-ReLU prevents deep learning models fromsuffering dead neurons or vanishing gradient issues.It is a hybrid activation function that combines the properties of ReLU and Softsign.For positive inputs,Med-ReLU adopts the linear behavior of ReLU to avoid vanishing gradients,while for negative inputs,it exhibits the Softsign’s polynomial convergence,ensuring robust training and avoiding inactive neurons across the training set.The training performance and segmentation accuracy ofMed-ReLU have been thoroughly evaluated,demonstrating stable learning behavior and resistance to overfitting.It consistently outperforms state-of-the-art activation functions inmedical image segmentation tasks.Designed as a parameter-free function,Med-ReLU is simple to implement in complex deep learning architectures,and its effectiveness spans various neural network models and anomaly detection scenarios. 展开更多
关键词 Medical image segmentation U-Net deep learning models activation function
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Implicit neural representation based on optoelectronic periodic nonlinear activation
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作者 Jiawei Gu Yulong Huang +2 位作者 Zijie Chen Mu Ku Chen Zihan Geng 《Advanced Photonics Nexus》 2025年第6期132-140,共9页
Implicit neural representation(INR)networks break through the accuracy and resolution limitations of traditional discrete representations by modeling high-dimensional data as continuously differentiable implicit neura... Implicit neural representation(INR)networks break through the accuracy and resolution limitations of traditional discrete representations by modeling high-dimensional data as continuously differentiable implicit neural networks,enabling lossless compression and efficient reconstruction of details in a compact form.However,an optical-assisted INR network has yet to be demonstrated.INR networks require high nonlinearity,whereas implementing analog nonlinear activation in photonic neural networks is a challenge.Inspired by the inherent physical properties of modulators,we propose an optoelectronic nonlinear activation and implement it on the image reconstruction task.Simulations and experiments demonstrate that the proposed optoelectronic periodic neural network can represent images and perform image reconstruction with excellent results.This approach empowers complex image reconstruction with high-frequency details and reduces the amount of required hardware.Our method enables the development of compact,efficient optoelectronic neural networks,utilizing repeatable modular units for scalable and practical high-performance computing.It can enable scene generation and compression in biomedicine,autonomous driving,and augmented reality/virtual reality. 展开更多
关键词 optical neural network optical signal processing nonlinear activation function
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Electrochemically reduced graphene oxide with enhanced electrocatalytic activity toward tetracycline detection 被引量:4
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作者 胥燕燕 高明明 +4 位作者 张国辉 王新华 李佳佳 王曙光 桑元华 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第11期1936-1942,共7页
An electrochemically reduced graphene oxide sample, ERGO_0.8v, was prepared by electrochemical reduction of graphene oxide (GO) at -0.8 V, which shows unique electrocatalytic activity toward tetracycline (TTC) det... An electrochemically reduced graphene oxide sample, ERGO_0.8v, was prepared by electrochemical reduction of graphene oxide (GO) at -0.8 V, which shows unique electrocatalytic activity toward tetracycline (TTC) detection compared to the ERGO-12v (GO applied to a negative potential of-1.2 V), GO, chemically reduced GO (CRGO)-modified glassy carbon electrode (GC) and bare GC electrodes. The redox peaks of TTC on an ERGO-0.8v-modifled glass carbon electrode (GC/ERGO-0.8v) were within 0-0.5 V in a pH 3.0 buffer solution with the oxidation peak current correlating well with TTC concentration over a wide range from 0.1 to 160 mg/L Physical characterizations with Fourier transform infrared (FT-IR), Raman, and X-ray photoelectron spectroscopies (XPS) demonstrated that the oxygen-containing functional groups on GO diminished after the electrochemical reduction at -0.8 V, yet still existed in large amounts, and the defect density changed as new sp2 domains were formed. These changes demonstrated that this adjustment in the number of oxygen-containing groups might be the main factor affecting the electrocatalytic behavior of ERGO. Additionally, the defect density and sp2 domains also exert a profound influence on this behavior. A possible mechanism for the TTC redox reaction at the GC/ERGO-0.8v electrode is also presented. This work suggests that the electrochemical reduction is an effective method to establish new catalytic activities of GO by setting appropriate parameters. 展开更多
关键词 Electrochemically reduced graphene oxide Electrochemical detection Tetracycline Electrocatalytic activity Oxygen-containing functional groups
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Progress on the melanoidins produced by the Maillard reaction of fermented food and traditional Chinese medicine
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作者 Guang-Zhen Cao Si-Yi Zhang +4 位作者 Yao-Song Yang Qing He Xin-Xian Song Fei Long Teng Peng 《Food and Health》 2024年第4期10-18,共9页
FMs(Food-borne melanoidins)are brown high molecular weight polymers formed by the Mailiard reaction between carbohydrates and nitrogen-containing compounds during the processing of food or Traditional Chinese Medicine... FMs(Food-borne melanoidins)are brown high molecular weight polymers formed by the Mailiard reaction between carbohydrates and nitrogen-containing compounds during the processing of food or Traditional Chinese Medicine(TCM),and are widely found in food-borne products such as TCM concoctions,bakery,brewing,soy sauce,ferment and other food-borne products.FMs not only have a variety of biological activities,such as antioxidant,antibacterial,immunomodulation,regulation of intestinal flora,etc.,and can change the color,aroma and taste of food.The diversity of its components has become a research hotspot at home and abroad in recent years,with a wide range of application prospects.Therefore,this paper summarizes the existing information on FMs at home and abroad,mainly describes their preparation process,physicochemical properties,structural characteristics and functional activity research progress.Typical FMs,such as coffee,biscuits,wine and soy sauce in daily food,and Polygonatum,Perilla oil,Black ginseng,and Red jujube in T,were highlighted.Summarising the current status of research between the chemistry and pharmacodynamics of relevant FMs and presenting challenges and future recommendations for melanoidin research.In future research on FMs,one should pay more attention to basic research,especially isolation and purification and generation mechanisms,to further demonstrate the biological activity of FMs in vivo and in clinical trials.Thus,the potential value of its existence is deeply exploited to meet the needs of technology,production and health. 展开更多
关键词 Food-borne melanoidins Physical and chemical properties Structure functional activities Application prospects
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Chip-Based High-Dimensional Optical Neural Network 被引量:9
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作者 Xinyu Wang Peng Xie +1 位作者 Bohan Chen Xingcai Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第12期570-578,共9页
Parallel multi-thread processing in advanced intelligent processors is the core to realize high-speed and high-capacity signal processing systems.Optical neural network(ONN)has the native advantages of high paralleliz... Parallel multi-thread processing in advanced intelligent processors is the core to realize high-speed and high-capacity signal processing systems.Optical neural network(ONN)has the native advantages of high parallelization,large bandwidth,and low power consumption to meet the demand of big data.Here,we demonstrate the dual-layer ONN with Mach-Zehnder interferometer(MZI)network and nonlinear layer,while the nonlinear activation function is achieved by optical-electronic signal conversion.Two frequency components from the microcomb source carrying digit datasets are simultaneously imposed and intelligently recognized through the ONN.We successfully achieve the digit classification of different frequency components by demultiplexing the output signal and testing power distribution.Efficient parallelization feasibility with wavelength division multiplexing is demonstrated in our high-dimensional ONN.This work provides a high-performance architecture for future parallel high-capacity optical analog computing. 展开更多
关键词 Integrated optics Optical neural network High-dimension Mach-Zehnder interferometer Nonlinear activation function Parallel high-capacity analog computing
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Complex-Valued Neural Networks:A Comprehensive Survey 被引量:8
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作者 ChiYan Lee Hideyuki Hasegawa Shangce Gao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第8期1406-1426,共21页
Complex-valued neural networks(CVNNs)have shown their excellent efficiency compared to their real counterparts in speech enhancement,image and signal processing.Researchers throughout the years have made many efforts ... Complex-valued neural networks(CVNNs)have shown their excellent efficiency compared to their real counterparts in speech enhancement,image and signal processing.Researchers throughout the years have made many efforts to improve the learning algorithms and activation functions of CVNNs.Since CVNNs have proven to have better performance in handling the naturally complex-valued data and signals,this area of study will grow and expect the arrival of some effective improvements in the future.Therefore,there exists an obvious reason to provide a comprehensive survey paper that systematically collects and categorizes the advancement of CVNNs.In this paper,we discuss and summarize the recent advances based on their learning algorithms,activation functions,which is the most challenging part of building a CVNN,and applications.Besides,we outline the structure and applications of complex-valued convolutional,residual and recurrent neural networks.Finally,we also present some challenges and future research directions to facilitate the exploration of the ability of CVNNs. 展开更多
关键词 Complex activation function complex backpropagation algorithm complex-valued learning algorithm complex-valued neural network deep learning
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A unique 3D microporous MOF constructed by cross-linking 1D coordination polymer chains for effectively selective separation of CO_(2)/CH4 and C_(2)H_(2)/CH_(4) 被引量:4
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作者 Yu-Pei Xia Chen-Xue Wang +1 位作者 Mei-Hui Yu Xian-He Bu 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第3期1153-1156,共4页
Selective separation of CO_(2)/CH_(4)and C2 H_(2)/CH_(4)are promising for their high-purity industrial demand and scientific research on account of the similar molecular radius and physical properties.In this work,a u... Selective separation of CO_(2)/CH_(4)and C2 H_(2)/CH_(4)are promising for their high-purity industrial demand and scientific research on account of the similar molecular radius and physical properties.In this work,a unique 3 D microporous MOF material[Cu(SiF6)(sdi)2]·solvents(1,sdi=1,1’-sulfonyldiimidazole)was successfully constructed by cross-linking 1 D coordination polymer chains.The dense functional active sites on the inner walls of the channel of la can provide strong binding affinities to CO_(2),C2 H_(2),and thus effectively improve the gas separation performance of CO_(2)/CH_(4)and C2 H_(2)/CH_(4). 展开更多
关键词 Metal-organic framework Cross-linking Selective separation Dense functional active site
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