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Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity
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作者 Moawiah M.Naffaa 《Neural Regeneration Research》 SCIE CAS 2025年第6期1565-1581,共17页
Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inh... Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. Moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased complexity and restructuring of neural network structures, as well as the addition of new granule granule cells that aid in olfactory adaptation. Additionally, the manuscript underscores the importance of employing precise methodologies to elucidate the specific roles of adult neurogenesis amidst conflicting data and varying experimental paradigms. Understanding these processes is essential for gaining insights into the complexities of olfactory function and behavior. 展开更多
关键词 network adaptability NEUROGENESIS neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity
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基于双随机森林的发热待查智能诊断方法
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作者 杜建超 丁俊瑶 +5 位作者 赵梦楠 连建奇 陈天艳 WU Yuan 周云 石磊 《生物医学工程学进展》 CAS 2024年第3期197-205,共9页
在机器学习预测模型中,不平衡数据集会降低少数类的预测准确性。针对发热待查数据集的不平衡特性,该文提出了一种基于K-Means聚类欠采样的双随机森林病因预测方法。首先通过K-Means聚类欠采样构建一个平衡数据集,并在此基础上创建一个基... 在机器学习预测模型中,不平衡数据集会降低少数类的预测准确性。针对发热待查数据集的不平衡特性,该文提出了一种基于K-Means聚类欠采样的双随机森林病因预测方法。首先通过K-Means聚类欠采样构建一个平衡数据集,并在此基础上创建一个基于CART投票机制的随机森林预测模型。然后对初始数据集用同样的方法创建一个随机森林预测模型。最后将两个随机森林预测模型联合,使用两者的CART一起投票预测。该文提出的方法增加了CART的数量,在保持原有数据集特性的同时,提高了少数类的投票权重。在发热待查数据集上的实验表明,该文所提方法不仅改善了少数类的预测性能,对其他类别的预测性能也有一定程度的提升。 展开更多
关键词 智能诊断 机器学习 发热待查 随机森林 不平衡数据集
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The neurovascular unit-on-a-chip:modeling ischemic stroke to stem cell therapy 被引量:1
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作者 Seonghun Kim Minjun Kim +1 位作者 Gerald A.Grant Wonjae Lee 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1431-1432,共2页
The neurovascular unit and stem cell therapy in ischemic stroke:Ischemic stroke,accounts for approximately 85% of all stroke incidents and is a major global health burden.It is the leading cause of disability and deat... The neurovascular unit and stem cell therapy in ischemic stroke:Ischemic stroke,accounts for approximately 85% of all stroke incidents and is a major global health burden.It is the leading cause of disability and death worldwide,posing immense societal and economic challenges due to the long-term care required for stro ke survivors and the significant healthcare costs associated with its treatment and management(Amarenco et al.,2009). 展开更多
关键词 DEATH UNIT
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治疗相关神经内分泌前列腺癌机制研究与靶向治疗新进展
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作者 黄教悌 胡菁 韩博 《北京大学学报(医学版)》 CAS CSCD 北大核心 2024年第4期557-561,共5页
前列腺癌是男性泌尿生殖系统最常见的恶性肿瘤,我国前列腺癌新发病例临床分期偏晚,Gleason级别较高,临床上多表现为进展期前列腺癌,已失去手术机会[1]。雄激素剥夺治疗(androgen deprivation therapy,ADT)是进展期前列腺癌的主要治疗手... 前列腺癌是男性泌尿生殖系统最常见的恶性肿瘤,我国前列腺癌新发病例临床分期偏晚,Gleason级别较高,临床上多表现为进展期前列腺癌,已失去手术机会[1]。雄激素剥夺治疗(androgen deprivation therapy,ADT)是进展期前列腺癌的主要治疗手段,可显著抑制前列腺癌的进展,但是几乎所有患者在治疗12~18个月后进展为更具侵袭性的去势抵抗性前列腺癌(castration resistant prostate cancer,CRPC)[2]。 展开更多
关键词 神经内分泌前列腺癌 谱系可塑性 肿瘤异质性 靶向治疗
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Preface 被引量:1
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作者 Andrea Bertozzil Ron Fedkiw +5 位作者 Frederic Gibou Chiu-Yen Kao Chi-Wang Shu Richard Tsai Wotao Yin Hong-Kai Zhao 《Communications on Applied Mathematics and Computation》 EI 2024年第2期755-756,共2页
During April 20-22,2022,colleagues and friends gathered at the Institute of Pure&Applied Mathematics(IPAM),at the University of California at Los Angeles to celebrate Professor Stanley Osher's 8Oth birthday in... During April 20-22,2022,colleagues and friends gathered at the Institute of Pure&Applied Mathematics(IPAM),at the University of California at Los Angeles to celebrate Professor Stanley Osher's 8Oth birthday in a conference focusing on recent developments in"Optimization,Shape analysis,High-dimensional differential equations in science and Engineering,and machine learning Research(OSHER)"This conference hosted in-person talks by mathematicians,scientists,and industrial professionals worldwide.Those who could not attend extended their warm regards and expressed their appreciation for Professor Osher. 展开更多
关键词 Stanley gathered BIRTHDAY
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Downstaging strategies for unresectable hepatocellular carcinoma
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作者 Georgia Sofia Karachaliou Nikolaos Dimitrokallis Dimitrios P Moris 《World Journal of Gastroenterology》 SCIE CAS 2024年第20期2731-2733,共3页
A significant number of patients with hepatocellular carcinoma(HCC)are usually diagnosed in advanced stages,that leads to inability to achieve cure.Palliative options are focusing on downstaging a locally advanced dis... A significant number of patients with hepatocellular carcinoma(HCC)are usually diagnosed in advanced stages,that leads to inability to achieve cure.Palliative options are focusing on downstaging a locally advanced disease.It is wellsupported in the literature that patients with HCC who undergo successful conversion therapy followed by curative-intent surgery may achieve a significant survival benefit compared to those who receive chemotherapy alone or those who are successfully downstaged with conversion therapy but not treated with surgery.Hepatic artery infusion chemotherapy can be a potential downstaging strategy,since recent studies have demonstrated excellent outcomes in patients with colorectal liver metastatic disease as well as primary liver malignancies. 展开更多
关键词 Unresectable hepatocellular carcinoma Hepatic arterial infusion chemotherapy DOWNSTAGING Hepatocellular carcinoma
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Innovative pathways allow safe discharge of mild acute pancreatitis from the emergency room
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作者 Darshan J Kothari Sunil G Sheth 《World Journal of Gastroenterology》 SCIE CAS 2024年第11期1475-1479,共5页
Acute pancreatitis(AP)is a leading cause of gastrointestinal-related hospitalizations in the United States,resulting in 300000 admissions per year with an estimated cost of over$2.6 billion annually.The severity of AP... Acute pancreatitis(AP)is a leading cause of gastrointestinal-related hospitalizations in the United States,resulting in 300000 admissions per year with an estimated cost of over$2.6 billion annually.The severity of AP is determined by the presence of pancreatic complications and end-organ damage.While moderate/severe pancreatitis can be associated with significant morbidity and mortality,the majority of patients have a mild presentation with an uncomplicated course and mortality rate of less than 2%.Despite favorable outcomes,the majority of mild AP patients are admitted,contributing to healthcare cost and burden.In this Editorial we review the performance of an emergency department(ED)pathway for patients with mild AP at a tertiary care center with the goal of reducing hospitalizations,resource utilization,and costs after several years of implementation of the pathway.We discuss the clinical course and outcomes of mild AP patients enrolled in the pathway who were successfully discharged from the ED compared to those who were admitted to the hospital,and identify predictors of successful ED discharge to select patients who can potentially be triaged to the pathway.We conclude that by implementing innovative clinical pathways which are established and reproducible,selected AP patients can be safely discharged from the ED,reducing hospitalizations and healthcare costs,without compromising clinical outcomes.We also identify a subset of patients most likely to succeed in this pathway. 展开更多
关键词 Emergency department Mild pancreatitis PATHWAYS HOSPITALIZATION PREDICTORS
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Direct anterior compared to posterior approach for hip hemiarthroplasty following femoral neck fractures
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作者 Kevin A Wu Alexandra N Krez Albert T Anastasio 《World Journal of Orthopedics》 2024年第6期605-607,共3页
The differences in complication rates between the direct anterior and posterior approaches for hemiarthroplasty in elderly patients with femoral neck fractures are not yet fully understood.Dislocation,a severe complic... The differences in complication rates between the direct anterior and posterior approaches for hemiarthroplasty in elderly patients with femoral neck fractures are not yet fully understood.Dislocation,a severe complication associated with increased mortality and often requiring additional surgery,may occur less frequently with the direct anterior approach compared to the posterior approach.Careful consideration of patient demographics is essential when planning the surgical approach.Future research in this area should focus on robust randomized controlled trials involving elderly patients recovering from femoral neck fractures. 展开更多
关键词 Direct anterior approach Posterior approach HEMIARTHROPLASTY Femoral neck fractures ARTHROPLASTY DISLOCATION Surgical technique
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Subsequent total joint arthroplasty: Are we learning from the first stage?
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作者 Christine Jiang Wu Colin Penrose +3 位作者 Sean Patrick Ryan Michael Paul Bolognesi Thorsten Markus Seyler Samuel Secord Wellman 《World Journal of Orthopedics》 2024年第3期230-237,共8页
BACKGROUND With the increasing incidence of total joint arthroplasty(TJA),there is a desire to reduce peri-operative complications and resource utilization.As degenerative conditions progress in multiple joints,many p... BACKGROUND With the increasing incidence of total joint arthroplasty(TJA),there is a desire to reduce peri-operative complications and resource utilization.As degenerative conditions progress in multiple joints,many patients undergo multiple proce-dures.AIM To determine if both physicians and patients learn from the patient’s initial arth-roplasty,resulting in improved outcomes following the second procedure.METHODS The institutional database was retrospectively queried for primary total hip arth-roplasty(THA)and total knee arthroplasty(TKA).Patients with only unilateral THA or TKA,and patients undergoing same-day bilateral TJA,were excluded.Patient demographics,comorbidities,and implant sizes were collected at the time of each procedure and patients were stratified by first vs second surgery.Outcome metrics evaluated included operative time,length of stay(LOS),disposition,90-d readmissions and emergency department(ED)visits.RESULTS A total of 642 patients,including 364 undergoing staged bilateral TKA and 278 undergoing bilateral THA,were analyzed.There was no significant difference in demographics or comorbidities between the first and second procedure,which were separated by a mean of 285 d.For THA and TKA,LOS was significantly less for the second surgery,with 66%of patients having a shorter hospitalization(P<0.001).THA patients had significantly decreased operative time only when the same sized implant was utilized(P=0.025).The vast majority(93.3%)of patients were discharged to the same type of location following their second surgery.However,when a change in disposition was present from the first surgery,patients were significantly more likely to be discharged to home after the second procedure(P=0.033).There was no difference between procedures for post-operative readmissions(P=0.438)or ED visits(P=0.915).CONCLUSION After gaining valuable experience recovering from the initial surgery,a patient’s perioperative outcomes are improved for their second TJA.This may be the result of increased confidence and decreased anxiety,and it supports the theory that enhanced patient education pre-operatively may improve outcomes.For the surgical team,the second procedure of a staged THA is more efficient,although this finding did not hold for TKA. 展开更多
关键词 Staged total joint arthroplasty Asynchronous total joint arthroplasty Subsequent total joint arthroplasty Contralateral total joint arthroplasty Perioperative outcomes
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Smoking cessation prior to elective total joint arthroplasty results in sustained abstinence postoperatively
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作者 Billy Insup Kim Jeffrey O'Donnell +4 位作者 Colleen M Wixted Thorsten Markus Seyler William A Jiranek Michael Paul Bolognesi Sean Patrick Ryan 《World Journal of Orthopedics》 2024年第7期627-634,共8页
BACKGROUND Tobacco use is a well-documented modifiable risk factor for perioperative complications.AIM To determine the tobacco abstinence rates of patients who made cessation efforts prior to a total joint arthroplas... BACKGROUND Tobacco use is a well-documented modifiable risk factor for perioperative complications.AIM To determine the tobacco abstinence rates of patients who made cessation efforts prior to a total joint arthroplasty(TJA)procedure.METHODS A retrospective evaluation was performed on 88 self-reported tobacco users who underwent TJA between 2014-2022 and had tobacco cessation dates within 3 mo of surgery.Eligible patients were contacted via phone survey to understand their tobacco use pattern,and patient reported outcomes.A total of 37 TJA patients participated.RESULTS Our cohort was on average 61-years-old,60%(n=22)women,with an average body mass index of 30 kg/m^(2).The average follow-up time was 2.9±1.9 years.A total of 73.0%(n=27)of patients endorsed complete abstinence from tobacco use prior to surgery.Various cessation methods were used perioperatively including prescription therapy(13.5%),over the counter nicotine replacement(18.9%),cessation programs(5.4%).At final follow up,43.2%(n=16)of prior tobacco smokers reported complete abstinence.Patients who were able to maintain cessation postoperatively had improved Patient-Reported Outcomes Measurement Information System(PROMIS)-10 mental health scores(49 vs 58;P=0.01),and hip dysfunction and osteoarthritis outcome score for joint replacement(HOOS.JR)scores(63 vs 82;P=0.02).No patients in this cohort had a prosthetic joint infection or required revision surgery.CONCLUSION We report a tobacco cessation rate of 43.2%in patients undergoing elective TJA nearly 3 years postoperatively.Patients undergoing TJA who were able to remain abstinent had improved PROMIS-10 mental health scores and HOOS.JR scores.The perioperative period provides clinicians a unique opportunity to assist active tobacco smokers with cessation efforts and improve postoperative outcomes. 展开更多
关键词 Smoking cessation Total joint arthroplasty OUTCOMES Tobacco use Postoperative abstinence
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Academic productivity correlates with industry earnings in foot and ankle fellowship programs in the United States:A retrospective analysis
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作者 Albert T Anastasio Anthony N Baumann +4 位作者 Kempland C Walley Kyle J Hitchman Conor O’Neill Jonathan Kaplan Samuel B Adams 《World Journal of Orthopedics》 2024年第2期129-138,共10页
BACKGROUND The study investigates the connection between academic productivity and industry earnings in foot and ankle orthopedic surgery fellowships.Utilizing metrics like the H-index and Open Payments Database(OPD)d... BACKGROUND The study investigates the connection between academic productivity and industry earnings in foot and ankle orthopedic surgery fellowships.Utilizing metrics like the H-index and Open Payments Database(OPD)data,it addresses a gap in understanding the relationship between scholarly achievements and financial outcomes,providing a basis for further exploration in this specialized medical field.AIM To elucidate the trends between academic productivity and industry earnings across foot and ankle orthopedic surgery fellowship programs in the United States.METHODS This study is a retrospective analysis of the relationship between academic productivity and industry earnings of foot and ankle orthopedic surgery fellowships at an individual faculty and fellowship level.Academic productivity was defined via H-index and recorded from the Scopus website.Industry earnings were recorded from the OPD.RESULTS Forty-eight foot and ankle orthopedic surgery fellowships(100%of fellowships)in the United States with a combined total of 165 physicians(95.9%of physicians)were included.Mean individual physician(n=165)total life-time earnings reported on the OPD website was United States Dollar(USD)451430.30±1851084.89(range:USD 25.16-21269249.85;median:USD 27839.80).Mean physician(n=165)H-index as reported on Scopus is 14.24±12.39(range:0-63;median:11).There was a significant but weak correlation between individual physician H-index and individual physician total life-time earnings(P<0.001;Spearman’s rho=0.334)and a significant and moderate positive correlation between combined fellowship H-index and total life-time earnings per fellowship(P=0.004,Spearman’s rho=0.409).CONCLUSION There is a significant and positive correlation between academic productivity and industry earnings at foot and ankle orthopedic surgery fellowships in the United States.This observation is true on an individual physician level as well as on a fellowship level. 展开更多
关键词 Sunshine act Foot and ankle Orthopedic surgery Orthopedic fellowship Industry earnings
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Molecular characterization of canine parvovirus type 2(CPV2)reveals a high prevalence of the CPV2c genotype among dogs sufering from diarrhea
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作者 Sajid Umar Di Gao +5 位作者 Semin Kim Yixi Cheng Zhenkun Fang Qiu Zhongqi Weidong Yu Benjamin D.Anderson 《Animal Diseases》 CAS 2024年第3期198-206,共9页
Canine parvovirus 2(CPV-2)is a highly contagious virus in dogs that typically causes hemorrhagic enteritis and a high mortality rate in unvaccinated puppies.The genetic variability and antigenic diversity of CPV-2 hin... Canine parvovirus 2(CPV-2)is a highly contagious virus in dogs that typically causes hemorrhagic enteritis and a high mortality rate in unvaccinated puppies.The genetic variability and antigenic diversity of CPV-2 hinder its efective prevention of infection by vaccination.To investigate the epidemiology and genetic characteristics of CPV-2 in China,rectal swabs from afected dogs were collected from diferent animal clinics in Kunshan from 2022 to 2023.Preliminary detection and capsid gene sequencing of CPV-2 were performed using previously described primers and protocols.The overall detection rate for CPV-2 was 16.5%(33/200).A signifcant association was found between the CPV-2-positivity and clinical signs,age,breed and vaccination status.Sequence analysis revealed the presence of CPV-2c genotypes in all positive samples,which were genetically similar to other Asian CPV-2c strains.Notably,four key mutations(A5G,F267Y,Y324I and Q370R)were detected in all isolates,and one novel mutation(I447M)was detected in three CPV-2 isolates.These mutations in the CPV-2 strains could impact vaccine efcacy and the efectiveness of the virus immune evasion.Surprisingly,no recombination events were observed between the identifed CPV-2c strains and reference strains from China.Our data revealed that amino acid residues 324,426 and 440 of VP2 may under strong selection pressure.This pattern of genetic variation in the CPV-2 lineage warrants continuous laboratory-based surveillance programs in other parts of China to better understand the pattern of seasonal distribution and association between emerging genotypes and the intensity of disease severity. 展开更多
关键词 Canine parvovirus DOGS Epidemiology Genetic diversity Phylogenetic analysis
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Effectiveness of mindfulness-based interventions on the well-being of healthcare workers:a systematic review and meta-analysis
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作者 Natasha Yixuan Ong Finn Jing Jie Teo +4 位作者 Jane Zi Ying Ee Chun En Yau Julian Thumboo Hiang Khoon Tan Qin Xiang Ng 《General Psychiatry》 CSCD 2024年第3期335-344,共10页
Background Growing evidence attests to the efficacy of mindfulness-based interventions(MBIs),but their effectiveness for healthcare workers remains uncertain.Aims To evaluate the evidence for MBIs in improving healthc... Background Growing evidence attests to the efficacy of mindfulness-based interventions(MBIs),but their effectiveness for healthcare workers remains uncertain.Aims To evaluate the evidence for MBIs in improving healthcare workers’psychological well-being.Methods A systematic literature search was conducted on Medline,Embase,Cumulative Index for Nursing and Allied Health Literature,PsycINFO and Cochrane Central Register of Controlled Trials up to 31 August 2022 using the keywords‘healthcare worker’,‘doctor’,‘nurse’,‘allied health’,‘mindfulness’,‘wellness’,‘workshop’and‘program’.Randomised controlled trials with a defined MBI focusing on healthcare workers and quantitative outcome measures related to subjective or psychological well-being were eligible for inclusion.R V.4.0.3 was used for data analysis,with the standardised mean difference as the primary outcome,employing DerSimonian and Laird’s random effects model.Grading of Recommendations,Assessment,Development and Evaluation framework was used to evaluate the quality of evidence.Cochrane’s Risk of Bias 2 tool was used to assess the risk of bias in the included studies.Results A total of 27 studies with 2506 participants were included,mostly from the USA,involving various healthcare professions.MBIs such as stress reduction programmes,apps,meditation and training showed small to large effects on anxiety,burnout,stress,depression,psychological distress and job strain outcomes of the participants.Positive effects were also seen in self-compassion,empathy,mindfulness and well-being.However,long-term outcomes(1 month or longer postintervention)varied,and the effects were not consistently sustained.Conclusions MBIs offer short-term benefits in reducing stress-related symptoms in healthcare workers.The review also highlights limitations such as intervention heterogeneity,reduced power in specific subgroup analyses and variable study quality. 展开更多
关键词 NURSE SUSTAINED workers
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Advancements in Photovoltaic Panel Fault Detection Techniques
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作者 Junyao Zheng 《Journal of Materials Science and Chemical Engineering》 2024年第6期1-11,共11页
This paper examines the progression and advancements in fault detection techniques for photovoltaic (PV) panels, a target for optimizing the efficiency and longevity of solar energy systems. As the adoption of PV tech... This paper examines the progression and advancements in fault detection techniques for photovoltaic (PV) panels, a target for optimizing the efficiency and longevity of solar energy systems. As the adoption of PV technology grows, the need for effective fault detection strategies becomes increasingly paramount to maximize energy output and minimize operational downtimes of solar power systems. These approaches include the use of machine learning and deep learning methodologies to be able to detect the identified faults in PV technology. Here, we delve into how machine learning models, specifically kernel-based extreme learning machines and support vector machines, trained on current-voltage characteristic (I-V curve) data, provide information on fault identification. We explore deep learning approaches by taking models like EfficientNet-B0, which looks at infrared images of solar panels to detect subtle defects not visible to the human eye. We highlight the utilization of advanced image processing techniques and algorithms to exploit aerial imagery data, from Unmanned Aerial Vehicles (UAVs), for inspecting large solar installations. Some other techniques like DeepLabV3 , Feature Pyramid Networks (FPN), and U-Net will be detailed as such tools enable effective segmentation and anomaly detection in aerial panel images. Finally, we discuss implications of these technologies on labor costs, fault detection precision, and sustainability of PV installations. 展开更多
关键词 Photovoltaic Panels Fault Detection Deep Learning Image Processing
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一氧化氮对水稻叶片中由镧引起的氧化胁迫的缓解作用 被引量:16
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作者 肖强 茹巧美 +3 位作者 吴飞华 黄旋 裴真明 郑海雷 《中国稀土学报》 CAS CSCD 北大核心 2007年第6期745-750,共6页
研究了一氧化氮(NO)对水稻中由稀土元素镧诱导的抗氧化活性的影响。结果表明,在100μmol.L-1氯化镧处理的水稻幼苗中加入10μmol.L-1NO供体硝普钠(sodium nitroprusside,SNP),可以显著抑制镧从水稻根部向叶片的转运。镧处理显著降低超... 研究了一氧化氮(NO)对水稻中由稀土元素镧诱导的抗氧化活性的影响。结果表明,在100μmol.L-1氯化镧处理的水稻幼苗中加入10μmol.L-1NO供体硝普钠(sodium nitroprusside,SNP),可以显著抑制镧从水稻根部向叶片的转运。镧处理显著降低超氧化物歧化酶(superoxidedismutase,SOD)活性和还原型谷胱甘肽(reduced glutathione,GSH)含量,促进叶片过氧化氢(H2O2)含量上升。而NO则可明显阻断镧引起的这些效应,缓解镧引起的氧化胁迫,即NO缓解了高浓度镧对水稻的毒性。 展开更多
关键词 一氧化氮 抗氧化酶 氧化胁迫 水稻 稀土
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我国循证护理实践中证据应用概念模式的构建 被引量:48
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作者 成磊 冯升 +1 位作者 胡雁 Marrion E.Broome 《护理学杂志》 CSCD 北大核心 2019年第3期72-77,共6页
目的构建我国循证护理实践中证据应用概念模式。方法采用建构扎根理论的方法对参与我国大陆24项以证据应用为目的的循证护理实践项目的 56名人员进行了非结构式个人深入访谈,首先通过初始编码分析转录资料,然后进行聚焦编码同时收集项... 目的构建我国循证护理实践中证据应用概念模式。方法采用建构扎根理论的方法对参与我国大陆24项以证据应用为目的的循证护理实践项目的 56名人员进行了非结构式个人深入访谈,首先通过初始编码分析转录资料,然后进行聚焦编码同时收集项目相关文本资料。结果构建了以生根为核心的我国循证护理实践中证据应用过程的概念模式,包括证据应用的过程、影响因素和一线护理管理者推动证据应用的领导力三部分。结论证据应用是一个具有四个阶段的持续循环,证据应用的影响因素需持续评估,并重视护理管理者在证据应用中的作用。来自卫生保健系统中的各个层面的人士需要积极参与循证护理实践,在系统层面营造支持性的氛围,采用有针对性的应用策略,有效并可持续地使循证护理理念和证据内容在系统流程、日常护理实践和护士专业能力发展中生根。 展开更多
关键词 中国 循证实践 证据应用 护理 生根
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胞外Ca^(2+)信号——动植物中的第一信使 被引量:10
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作者 赵昕 裴真明 何奕昆 《遗传》 CAS CSCD 北大核心 2007年第3期269-275,共7页
钙离子作为重要的胞内第二信使,控制着许多细胞的功能,人们对此已经研究得比较深入。然而最近发现的一些细胞表面胞外Ca2+探测器使我们想到是否在胞外环境中,钙离子也具有信号分子的功能。钙离子传感器包括已经研究得比较清楚的胞外Ca2... 钙离子作为重要的胞内第二信使,控制着许多细胞的功能,人们对此已经研究得比较深入。然而最近发现的一些细胞表面胞外Ca2+探测器使我们想到是否在胞外环境中,钙离子也具有信号分子的功能。钙离子传感器包括已经研究得比较清楚的胞外Ca2+敏感受体—最初从甲状旁腺分离的G-耦联蛋白受体(CaR),另外,还有其他受体、通道和膜蛋白也都对胞外[Ca2+]的变化很敏感。最近从拟南芥保卫细胞中克隆到一个胞外钙离子受体蛋白(CAS),通过胞外钙离子的变化引起胞内钙离子信号。这些受体蛋白的克隆,使人们确信Ca2+在细胞中可以发挥第一信使的功能。 展开更多
关键词 CA^2+ 胞外Ca^2+敏感受体(caR) 胞外钙离子受体(CAS)
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白令海楚科奇海的海冰范围变化特征 被引量:9
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作者 胡宪敏 苏洁 +1 位作者 赵进平 Genevieve Hiltebrand 《冰川冻土》 CSCD 北大核心 2007年第1期53-60,共8页
白令海和楚科奇海位于北极太平洋一侧的海冰外缘线附近,具有较强烈的气冰海相互作用.采用滑动t检验和小波分析方法对白令海和楚科奇海1953—2004年海冰范围的年际变化、年代际变化和总体趋势变化进行分析.结果表明:20世纪70年代后期,海... 白令海和楚科奇海位于北极太平洋一侧的海冰外缘线附近,具有较强烈的气冰海相互作用.采用滑动t检验和小波分析方法对白令海和楚科奇海1953—2004年海冰范围的年际变化、年代际变化和总体趋势变化进行分析.结果表明:20世纪70年代后期,海冰范围在白令海存在显著的均值突变现象,而楚科奇海在对应阶段则表现为更明显的变频现象;在突变点前后两个时段里,阿留申低压中心低压加强、核心位置偏移以及对应风场分布的变化是导致白令海海冰范围明显缩小的主要动力原因.楚科奇海海冰范围的年际变化中存在由低频向高频变化的现象,该现象除了在局地气温变化中存在之外,在北冰洋区域风涡度、波弗特海纬向风、东西伯利亚海经向风等动力因素中也有所体现.因此,除热力因素外,动力因素引起的海冰的平流与该变频现象也存在一定的联系. 展开更多
关键词 白令海 楚科奇海 海冰范围 突变 阿留申低压
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一氧化氮在植物中的信号分子功能研究:进展和展望 被引量:21
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作者 刘维仲 张润杰 +1 位作者 裴真明 何奕昆 《自然科学进展》 北大核心 2008年第1期10-24,共15页
一氧化氮(NO)是一种生物活性分子,越来越多的证据表明它是生物体内分布最为广泛的信号分子之一.NO作为植物生长发育的一个关键调节因子,能对各种生物或非生物胁迫产生应答,在植物生长发育与环境互作的协调过程中起着中枢性的作用.近年来... 一氧化氮(NO)是一种生物活性分子,越来越多的证据表明它是生物体内分布最为广泛的信号分子之一.NO作为植物生长发育的一个关键调节因子,能对各种生物或非生物胁迫产生应答,在植物生长发育与环境互作的协调过程中起着中枢性的作用.近年来,对于一氧化氮在植物中分子功能的研究取得了较大进展,特别是其信号转导功能、对基因表达的调控和植物体内NO稳态平衡的维持等方面.文中较全面地介绍了植物体内NO的合成、功能、信号转导、对基因表达的调控以及植物体内NO动态平衡的维持等方面研究的进展,并对该领域今后的研究进行了展望. 展开更多
关键词 一氧化氯 信号转导 信号分子 稳态平衡
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老年长期照护研究综述 被引量:28
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作者 曹艳春 王建云 《社会保障研究》 CSSCI 2013年第3期56-65,共10页
本文对长期照护概念从"长期"和"照护"两个方面进行剖析,从长期照护模式分类、长期照护评估机制、法律法规和保险制度等方面介绍各国研究状况,提出我国发展长期照护制度的建议:满足照护需求,构建合理的长期照护模式... 本文对长期照护概念从"长期"和"照护"两个方面进行剖析,从长期照护模式分类、长期照护评估机制、法律法规和保险制度等方面介绍各国研究状况,提出我国发展长期照护制度的建议:满足照护需求,构建合理的长期照护模式;发展老龄产业,培养优质的长期照护人才;健全法律法规,构建长期照护保险制度;提供护理津贴,合理分担财政负担;发展评估,及时干预老年人健康状况。 展开更多
关键词 长期照护 长期护理保险 长期照护模式
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