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Establishing minimum clinically important difference values for the Patient-Reported Outcomes Measurement Information System Physical Function, hip disability and osteoarthritis outcome score for joint reconstruction, and knee injury and osteoarthritis out 被引量:3
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作者 Man Hung Jerry Bounsanga +1 位作者 Maren W Voss Charles L Saltzman 《World Journal of Orthopedics》 2018年第3期41-49,共9页
AIM To establish minimum clinically important difference(MCID) for measurements in an orthopaedic patient population with joint disorders.METHODS Adult patients aged 18 years and older seeking care for joint condition... AIM To establish minimum clinically important difference(MCID) for measurements in an orthopaedic patient population with joint disorders.METHODS Adult patients aged 18 years and older seeking care for joint conditions at an orthopaedic clinic took the Patient-Reported Outcomes Measurement Information System Physical Function(PROMIS~? PF) computerized adaptive test(CAT), hip disability and osteoarthritis outcome score for joint reconstruction(HOOS JR), and the knee injury and osteoarthritis outcome score for joint reconstruction(KOOS JR) from February 2014 to April 2017. MCIDs were calculated using anchorbased and distribution-based methods. Patient reports of meaningful change in function since their first clinic encounter were used as an anchor.RESULTS There were 2226 patients who participated with a mean age of 61.16(SD = 12.84) years, 41.6% male, and 89.7% Caucasian. Mean change ranged from 7.29 to 8.41 for the PROMIS~? PF CAT, from 14.81 to 19.68 for the HOOS JR, and from 14.51 to 18.85 for the KOOS JR. ROC cut-offs ranged from 1.97-8.18 for the PF CAT, 6.33-43.36 for the HOOS JR, and 2.21-8.16 for the KOOS JR. Distribution-based methods estimated MCID values ranging from 2.45 to 21.55 for the PROMIS~? PF CAT; from 3.90 to 43.61 for the HOOS JR, and from 3.98 to 40.67 for the KOOS JR. The median MCID value in the range was similar to the mean change score for each measure and was 7.9 for the PF CAT, 18.0 for the HOOS JR, and 15.1 for the KOOS JR.CONCLUSION This is the first comprehensive study providing a wide range of MCIDs for the PROMIS? PF, HOOS JR, and KOOS JR in orthopaedic patients with joint ailments. 展开更多
关键词 Hhip DISABILITY and OSTEOARTHRITIS OUTCOME SCORE for JOINT reconstruction Patient-Reported OUTCOMES Measurement Information System Physical Function Knee injury and OSTEOARTHRITIS OUTCOME SCORE for JOINT reconstruction Minimum clinically important difference JOINT Physical function Minimum detectable change Arthroplasty Orthopaedics clinical OUTCOMES
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The potential mechanism and clinical application value of remote ischemic conditioning in stroke
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作者 Yajun Zhu Xiaoguo Li +6 位作者 Xingwei Lei Liuyang Tang Daochen Wen Bo Zeng Xiaofeng Zhang Zichao Huang Zongduo Guo 《Neural Regeneration Research》 SCIE CAS 2025年第6期1613-1627,共15页
Some studies have confirmed the neuroprotective effect of remote ischemic conditioning against stroke. Although numerous animal researches have shown that the neuroprotective effect of remote ischemic conditioning may... Some studies have confirmed the neuroprotective effect of remote ischemic conditioning against stroke. Although numerous animal researches have shown that the neuroprotective effect of remote ischemic conditioning may be related to neuroinflammation, cellular immunity, apoptosis, and autophagy, the exact underlying molecular mechanisms are unclear. This review summarizes the current status of different types of remote ischemic conditioning methods in animal and clinical studies and analyzes their commonalities and differences in neuroprotective mechanisms and signaling pathways. Remote ischemic conditioning has emerged as a potential therapeutic approach for improving stroke-induced brain injury owing to its simplicity, non-invasiveness, safety, and patient tolerability. Different forms of remote ischemic conditioning exhibit distinct intervention patterns, timing, and application range. Mechanistically, remote ischemic conditioning can exert neuroprotective effects by activating the Notch1/phosphatidylinositol 3-kinase/Akt signaling pathway, improving cerebral perfusion, suppressing neuroinflammation, inhibiting cell apoptosis, activating autophagy, and promoting neural regeneration. While remote ischemic conditioning has shown potential in improving stroke outcomes, its full clinical translation has not yet been achieved. 展开更多
关键词 Akt apoptosis autophagy cerebral perfusion cerebral vascular stenosis clinical transformation hemorrhagic stroke ischemic stroke NEUROINFLAMMATION neuroprotection Notch1 PI3K remote ischemic conditioning STROKE
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Cyberattack Ramifications, The Hidden Cost of a Security Breach
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作者 Meysam Tahmasebi 《Journal of Information Security》 2024年第2期87-105,共19页
In this in-depth exploration, I delve into the complex implications and costs of cybersecurity breaches. Venturing beyond just the immediate repercussions, the research unearths both the overt and concealed long-term ... In this in-depth exploration, I delve into the complex implications and costs of cybersecurity breaches. Venturing beyond just the immediate repercussions, the research unearths both the overt and concealed long-term consequences that businesses encounter. This study integrates findings from various research, including quantitative reports, drawing upon real-world incidents faced by both small and large enterprises. This investigation emphasizes the profound intangible costs, such as trade name devaluation and potential damage to brand reputation, which can persist long after the breach. By collating insights from industry experts and a myriad of research, the study provides a comprehensive perspective on the profound, multi-dimensional impacts of cybersecurity incidents. The overarching aim is to underscore the often-underestimated scope and depth of these breaches, emphasizing the entire timeline post-incident and the urgent need for fortified preventative and reactive measures in the digital domain. 展开更多
关键词 Artificial Intelligence (AI) Business Continuity Case Studies Copyright Cost-Benefit Analysis Credit Rating Cyberwarfare Cybersecurity Breaches Data Breaches Denial Of Service (DOS) Devaluation Of Trade Name Disaster Recovery Distributed Denial of Service (DDOS) Identity Theft Increased Cost to Raise Debt Insurance Premium Intellectual Property Operational Disruption Patent Post-Breach Customer Protection Recovery Point Objective (RPO) Recovery Time Objective (RTO) Regulatory Compliance Risk Assessment Service Level Agreement Stuxnet Trade Secret
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Clinical distribution and molecular profiling on postoperative colorectal cancer patients with different traditional Chinese medicine syndromes 被引量:1
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作者 Li-Jun Jin Ying Liu +12 位作者 Ming-Ming Zhang Xue-Meng Han Qiu-Jie Li Yu Xiang Bing-Tao Zhai Peng Chen Xia-Ying Chen Wen-Gang Wang Shui-Ping Liu Duan Ting Jiao Feng Tian Xie Xin-Bing Sui 《Traditional Medicine Research》 2020年第1期44-52,共9页
Background:Traditional Chinese medicine(TCM)syndrome,also named syndrome,are comprehensive and integral analyses of clinical information which helps to guide different individualized treatment prescriptions.Methods:Th... Background:Traditional Chinese medicine(TCM)syndrome,also named syndrome,are comprehensive and integral analyses of clinical information which helps to guide different individualized treatment prescriptions.Methods:Thirty healthy controls and 80 colorectal cancer(CRC)patients(including 33 Spleen Qi Deficiency syndrome,23 Dampness Heat syndrome,17 Blood Stasis syndrome and 7 other syndrome)were enrolled into this study.Human mRNAs were extracted from peripheral blood mononuclear cells.The gene expression for CRC patients with different TCM syndrome was determined by microarray and qRT-PCR.Results:Spleen Qi Deficiency,Dampness Heat and Blood Stasis were the most common syndromes in CRC patients.There is a significant difference was found in mRNA expression levels(especially for PIK3CA,STAT3,SOX9 and KDM5C)among Spleen Qi Deficiency,Dampness Heat and Blood Stasis syndrome groups.The higher mRNA levels of JNK1,TP53,MLH1,MSH6,PMS2,SOCS3,TCF7L2,FAM123B,PSAP,FBXW7,SALL4 and the lower expression of inflammatory cytokine IL-6 were found in Spleen Qi Deficiency group but not other syndrome types.The higher mRNA levels of KRAS,MUC16,EGFR,GRASP65,PIK3CA,MAPK7,CD24,STAT3,SLC11A1,Bcl-2,TXNDC17 and some inflammatory cytokines(IL-6,IL-23,TNF-a,CXCR4)were found in Dampness Heat group but not other syndrome types.Blood Stasis syndrome showed higher expression of SOX9,MLH1,MSH6,KDM5C,PCDH11X,PSAP and SALL4,and lower mRNA levels of PIK3CA,CD24,STAT3,CXCR4,TXNDC17 and TP53.The CRC patients with Dampness Heat syndrome might have a poor prognosis than other syndrome types.Conclusion:The identification of syndrome conditions had different impacts on CRC prognosis,and which might be related with different mRNA expression levels.Some oncogenes and pro-inflammatory cytokines were highly expressed in Dampness Heat group but not other syndrome types,suggesting that the CRC patients with Dampness Heat syndrome might have a poor prognosis.Our results prelimitarily uncovered the molecular basis of syndrome differences in CRC prognosis,a better understanding for TCM treatment of CRC. 展开更多
关键词 Traditional Chinese medicine clinical distribution Molecular profiling Colorectal cancer Syndrome differentiation Pattern diagnosis
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Analysis of DAR(1)/D/s Queue with Quasi-Negative Binomial-II as Marginal Distribution
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作者 Kanichukattu Korakutty Jose Bindu Abraham 《Applied Mathematics》 2011年第9期1159-1169,共11页
In this paper we consider the arrival process of a multiserver queue governed by a discrete autoregressive process of order 1 [DAR(1)] with Quasi-Negative Binomial Distribution-II as the marginal distribution. This di... In this paper we consider the arrival process of a multiserver queue governed by a discrete autoregressive process of order 1 [DAR(1)] with Quasi-Negative Binomial Distribution-II as the marginal distribution. This discrete time multiserver queueing system with autoregressive arrivals is more suitable for modeling the Asynchronous Transfer Mode(ATM) multiplexer queue with Variable Bit Rate (VBR) coded teleconference traffic. DAR(1) is described by a few parameters and it is easy to match the probability distribution and the decay rate of the autocorrelation function with those of measured real traffic. For this queueing system we obtained the stationary distribution of the system size and the waiting time distribution of an arbitrary packet with the help of matrix analytic methods and the theory of Markov regenerative processes. Also we consider negative binomial distribution, generalized Poisson distribution, Borel-Tanner distribution defined by Frank and Melvin(1960) and zero truncated generalized Poisson distribution as the special cases of Quasi-Negative Binomial Distribution-II. Finally, we developed computer programmes for the simulation and empirical study of the effect of autocorrelation function of input traffic on the stationary distribution of the system size as well as waiting time of an arbitrary packet. The model is applied to a real data of number of customers waiting for checkout in an airport and it is established that the model well suits this data. 展开更多
关键词 Discrete Autoregressive PROCESS of Order [DAR(1)] Multiserver ATM Multiplexer Matrix Analytic Methods MARKOV Renewal PROCESS MARKOV Regenerative Theory Teleconference Traffic Quasi-Negative Binomial distribution-II Generalized Poisson distribution Borel-Tanner distribution
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Effects of resveratrol in experimental and clinical non-alcoholic fatty liver disease 被引量:11
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作者 Sara Heebll Karen Louise Thomsen +3 位作者 Steen B Pedersen Hendrik Vilstrup Jacob George Henning Grnbk 《World Journal of Hepatology》 CAS 2014年第4期188-198,共11页
The prevalence of obesity and related conditions like non-alcoholic fatty liver disease(NAFLD) is increasing worldwide and therapeutic options are limited.Alternative treatment options are therefore intensively sought... The prevalence of obesity and related conditions like non-alcoholic fatty liver disease(NAFLD) is increasing worldwide and therapeutic options are limited.Alternative treatment options are therefore intensively sought after.An interesting candidate is the natural polyphenol resveratrol(RSV) that activates adenosinmonophosphate-activated protein kinase(AMPK) and silent information regulation-2 homolog 1(SIRT1).In addition,RSV has known anti-oxidant and anti-inflammatory effects.Here,we review the current evidence for RSVmediated effects on NAFLD and address the different aspects of NAFLD and non-alcoholic steatohepatitis(NASH) pathogenesis with respect to free fatty acid(FFA) flux from adipose tissue,hepatic de novo lipogenesis,inadequate FFA β-oxidation and additional intra- and extrahepatic inflammatory and oxidant hits.We review the in vivo evidence from animal studies and clinical trials.The abundance of animal studies reports a decrease in hepatic triglyceride accumulation,liver weight and a general improvement in histological fatty liver changes,along with a reduction in circulating insulin,glucose and lipid levels.Some studies document AMPK or SIRT1 activation,and modulation of relevant markers of hepatic lipogenesis,inflammation and oxidation status.However,AMPK/SIRT1-independent actions are also likely.Clinical trials are scarce and have primarily been performed with a focus on overweight/obese participants without a focus on NAFLD/NASH and histological liver changes.Future clinical studies with appropriate design are needed to clarify the true impact of RSV treatment in NAFLD/NASH patients. 展开更多
关键词 Non-alcoholic fatty liver disease NONALCOHOLIC STEATOHEPATITIS STEATOSIS RESVERATROL AMPactivated protein kinase Silent information regulation-2 homolog 1 ANTI-OXIDANTS Anti-inflammatory agents Animal studies clinical trial
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Prevalence and ecological factors affecting the distribution of plant-parasitic nematodes in Prunus groves in Spain
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作者 Ilenia Clavero-Camacho Antonio Archidona-Yuste +2 位作者 Carolina Cantalapiedra-Navarrete Pablo Castillo Juan Emilio Palomares-Rius 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期566-589,共24页
A wide survey was conducted to study plant-parasitic nematodes(PPNs)associated with Prunus groves in Spain.This research aimed to determine the prevalence and distribution of PPNs in Prunus groves,as well as the influ... A wide survey was conducted to study plant-parasitic nematodes(PPNs)associated with Prunus groves in Spain.This research aimed to determine the prevalence and distribution of PPNs in Prunus groves,as well as the influence of explanatory variables describing soil,climate and agricultural management in structuring the variation of PPNs community composition.A total of 218 sampling sites were surveyed and 84 PPN species belonging to 32 genera were identified based of an integrative taxonomic approach.PPN species considered as potential limiting factors in Prunus production,such as Meloidogyne arenaria,M.incognita,M.javanica,Pratylenchus penetrans and P.vulnus,were identified in this survey.Seven soil physico-chemical(C,Mg,N,Na,OM,P,pH and clay,loamy sand and sandy loam texture classes),four climate(Bio04,Bio05,Bio13 and Bio14)and four agricultural management variables(grove-use history less than 10 years,irrigation,apricot seedling rootstock,and Montclar rootstock)were identified as the most influential variables driving spatial patterns of PPNs communities.In particular,younger plantations showed higher values for species richness and diversity indices than groves cultivated for more than 20 years with Prunus spp.Our study increases the knowledge of the distribution and prevalence of PPNs associated with Prunus rhizosphere,as well as on the influence of explanatory variables driving the spatial structure PPNs communities,which has important implications for the successful design of sustainable management strategies in the future in this agricultural system. 展开更多
关键词 nematodes MELOIDOGYNE PRATYLENCHUS Paratylenchus ROOTSTOCK distribution soil grove-use ALMOND peach
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Fast-to-Clinic, Fast-to-Market in Biotech Innovation: Optimizing Chemistry Manufacturing & Controls (CMC) Excellence for Clinical and Commercial Success
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作者 Kishore Kumar Hotha 《Advances in Chemical Engineering and Science》 CAS 2024年第3期155-171,共17页
In the emerging world of biotech innovation, the fast-to-clinic/market strategy has emerged as a critical “mantra” for biotech, investors, and CDMOs. This approach addresses the escalating costs and complexities of ... In the emerging world of biotech innovation, the fast-to-clinic/market strategy has emerged as a critical “mantra” for biotech, investors, and CDMOs. This approach addresses the escalating costs and complexities of research and development by streamlining the path from concept to clinical trials and, ultimately, to market. The article delves into the intricacies of implementing a fast-to-clinic/market strategy, underlining the empowering role of strategic decision-making in preclinical and commercial stages. The plan advocates for a phase-appropriate approach, where the development decision is tailored to each phase of the product’s lifecycle. This ensures that resources are allocated efficiently, risks are managed effectively, and the product can move through the development pipeline accelerated without compromising quality or regulatory compliance. The article also discusses the role of CDMOs in facilitating rapid product development and the essential factors biotech companies must consider when selecting a partner for outsourcing. These factors include the CDMO’s expertise in navigating regulatory landscapes, technological capabilities, and ability to scale processes efficiently. Moreover, the article stresses the importance of agility and flexibility in the fast-to-clinic/market approach. Biotech companies are encouraged to adopt adaptable strategies that respond to the fast-evolving regulatory and market landscapes. 展开更多
关键词 Fast to Clinic INNOVATION CDMO CMC PREclinical FDA IND NDA ANDA BIOTECH
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Likelihood and Quadratic Distance Methods for the Generalized Asymmetric Laplace Distribution for Financial Data 被引量:1
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作者 Andrew Luong 《Open Journal of Statistics》 2017年第2期347-368,共22页
Maximum likelihood (ML) estimation for the generalized asymmetric Laplace (GAL) distribution also known as Variance gamma using simplex direct search algorithms is investigated. In this paper, we use numerical direct ... Maximum likelihood (ML) estimation for the generalized asymmetric Laplace (GAL) distribution also known as Variance gamma using simplex direct search algorithms is investigated. In this paper, we use numerical direct search techniques for maximizing the log-likelihood to obtain ML estimators instead of using the traditional EM algorithm. The density function of the GAL is only continuous but not differentiable with respect to the parameters and the appearance of the Bessel function in the density make it difficult to obtain the asymptotic covariance matrix for the entire GAL family. Using M-estimation theory, the properties of the ML estimators are investigated in this paper. The ML estimators are shown to be consistent for the GAL family and their asymptotic normality can only be guaranteed for the asymmetric Laplace (AL) family. The asymptotic covariance matrix is obtained for the AL family and it completes the results obtained previously in the literature. For the general GAL model, alternative methods of inferences based on quadratic distances (QD) are proposed. The QD methods appear to be overall more efficient than likelihood methods infinite samples using sample sizes n ≤5000 and the range of parameters often encountered for financial data. The proposed methods only require that the moment generating function of the parametric model exists and has a closed form expression and can be used for other models. 展开更多
关键词 M-ESTIMATORS CUMULANT Generating Function CHI-SQUARE Tests Generalized Hyperbolic distribution SIMPLEX Pattern Search Variance Gamma Minimum Distance VALUE at RISK Entropic VALUE at RISK European Call Option
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Clinical decision support for drug related events: Moving towards better prevention 被引量:2
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作者 Sandra L Kane-Gill Archita Achanta +1 位作者 John A Kellum Steven M Handler 《World Journal of Critical Care Medicine》 2016年第4期204-211,共8页
Clinical decision support(CDS) systems with automated alerts integrated into electronic medical records demonstrate efficacy for detecting medication errors(ME) and adverse drug events(ADEs). Critically ill patients a... Clinical decision support(CDS) systems with automated alerts integrated into electronic medical records demonstrate efficacy for detecting medication errors(ME) and adverse drug events(ADEs). Critically ill patients are at increased risk for ME, ADEs and serious negative outcomes related to these events. Capitalizing on CDS to detect ME and prevent adverse drug related events has the potential to improve patient outcomes. The key to an effective medication safety surveillance system incorporating CDS is advancing the signals for alerts by using trajectory analyses to predict clinical events, instead of waiting for these events to occur. Additionally, incorporating cutting-edge biomarkers into alert knowledge in an effort to identify the need to adjust medication therapy portending harm will advance the current state of CDS. CDS can be taken a step further to identify drug related physiological events, which are less commonly included in surveillance systems. Predictive models for adverse events that combine patient factors with laboratory values and biomarkers are being established and these models can be the foundation for individualized CDS alerts to prevent impending ADEs. 展开更多
关键词 Drug-related side effects and ADVERSE reactions DECISION support SYSTEMS clinical Medication errors Patient safety clinical pharmacy information SYSTEMS Intensive CARE units Critical CARE ADVERSE DRUG event clinical DECISION support SYSTEMS
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Epidemiological and clinical features,treatment status,and economic burden of traumatic spinal cord injury in China:a hospital-based retrospective study 被引量:2
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作者 Hengxing Zhou Yongfu Lou +32 位作者 Lingxiao Chen Yi Kang Lu Liu Zhiwei Cai David BAnderson Wei Wang Chi Zhang Jinghua Wang Guangzhi Ning Yanzheng Gao Baorong He Wenyuan Ding Yisheng Wang Wei Mei Yueming Song Yue Zhou Maosheng Xia Huan Wang Jie Zhao Guoyong Yin Tao Zhang Feng Jing Rusen Zhu Bin Meng Li Duan Zhongmin Zhang Desheng Wu Zhengdong Cai Lin Huang Zhanhai Yin Kainan Li Shibao Lu Shiqing Feng 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1126-1132,共7页
Traumatic spinal cord injury is potentially catastrophic and can lead to permanent disability or even death.China has the largest population of patients with traumatic spinal cord injury.Previous studies of traumatic ... Traumatic spinal cord injury is potentially catastrophic and can lead to permanent disability or even death.China has the largest population of patients with traumatic spinal cord injury.Previous studies of traumatic spinal cord injury in China have mostly been regional in scope;national-level studies have been rare.To the best of our knowledge,no national-level study of treatment status and economic burden has been performed.This retrospective study aimed to examine the epidemiological and clinical features,treatment status,and economic burden of traumatic spinal cord injury in China at the national level.We included 13,465 traumatic spinal cord injury patients who were injured between January 2013 and December 2018 and treated in 30 hospitals in 11 provinces/municipalities representing all geographical divisions of China.Patient epidemiological and clinical features,treatment status,and total and daily costs were recorded.Trends in the percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department and cost of care were assessed by annual percentage change using the Joinpoint Regression Program.The percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department did not significantly change overall(annual percentage change,-0.5%and 2.1%,respectively).A total of 10,053(74.7%)patients underwent surgery.Only 2.8%of patients who underwent surgery did so within 24 hours of injury.A total of 2005(14.9%)patients were treated with high-dose(≥500 mg)methylprednisolone sodium succinate/methylprednisolone(MPSS/MP);615(4.6%)received it within 8 hours.The total cost for acute traumatic spinal cord injury decreased over the study period(-4.7%),while daily cost did not significantly change(1.0%increase).Our findings indicate that public health initiatives should aim at improving hospitals’ability to complete early surgery within 24 hours,which is associated with improved sensorimotor recovery,increasing the awareness rate of clinical guidelines related to high-dose MPSS/MP to reduce the use of the treatment with insufficient evidence. 展开更多
关键词 China clinical features COSTS EPIDEMIOLOGY methylprednisolone sodium succinate METHYLPREDNISOLONE retrospective study traumatic spinal cord injury TREATMENT
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Binary Gravitational Search based Algorithm for Optimum Siting and Sizing of DG and Shunt Capacitors in Radial Distribution Systems
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作者 N. A. Khan S. Ghosh S. P. Ghoshal 《Energy and Power Engineering》 2013年第4期1005-1010,共6页
This paper presents a binary gravitational search algorithm (BGSA) is applied to solve the problem of optimal allotment of DG sets and Shunt capacitors in radial distribution systems. The problem is formulated as a no... This paper presents a binary gravitational search algorithm (BGSA) is applied to solve the problem of optimal allotment of DG sets and Shunt capacitors in radial distribution systems. The problem is formulated as a nonlinear constrained single-objective optimization problem where the total line loss (TLL) and the total voltage deviations (TVD) are to be minimized separately by incorporating optimal placement of DG units and shunt capacitors with constraints which include limits on voltage, sizes of installed capacitors and DG. This BGSA is applied on the balanced IEEE 10 Bus distribution network and the results are compared with conventional binary particle swarm optimization. 展开更多
关键词 Normal Load Flow Radial distribution System Distributed Generation SHUNT Capacitors BINARY Particle SWARM Optimization BINARY GRAVITATIONAL SEARCH Algorithm TOTAL line Loss TOTAL Voltage Deviation
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Optimal Partitioning of Distribution Networks for Micro-Grid Operation
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作者 Shane J. Kimble Divya T. Vedullapalli Elham B. Makram 《Journal of Power and Energy Engineering》 2017年第9期104-120,共17页
A great concern for the modern distribution grid is how well it can withstand and respond to adverse conditions. One way that utilities are addressing this issue is by adding redundancy to their systems. Likewise, dis... A great concern for the modern distribution grid is how well it can withstand and respond to adverse conditions. One way that utilities are addressing this issue is by adding redundancy to their systems. Likewise, distributed generation (DG) is becoming an increasingly popular asset at the distribution level and the idea of microgrids operating as standalone systems apart from the bulk electric grid is quickly becoming a reality. This allows for greater flexibility as systems can now take on exponentially more configurations than the radial, one-way distribution systems of the past. These added capabilities, however, make the system reconfiguration with a much more complex problem causing utilities to question if they are operating their distribution systems optimally. In addition, tools like Supervisory Control and Data Acquisition (SCADA) and Distribution Automation (DA) allow for systems to be reconfigured faster than humans can make decisions on how to reconfigure them. As a result, this paper seeks to develop an automated partitioning scheme for distribution systems that can respond to varying system conditions while ensuring a variety of operational constraints on the final configuration. It uses linear programming and graph theory. Power flow is calculated externally to the LP and a feedback loop is used to recalculate the solution if a violation is found. Application to test systems shows that it can reconfigure systems containing any number of loops resulting in a radial configuration. It can connect multiple sources to a single microgrid if more capacity is needed to supply the microgrid’s load. 展开更多
关键词 Distributed Generation (DG) Supervisory Control and Data Acquisition (SCADA) distribution Automation (DA) Fault Location Isolation and RESTORATION (FLISR) SELF-HEALING Network MICRO-GRID Smart Grid
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Pitfalls in spirometry: Clinical relevance
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作者 Andrea Antonelli Giulia Michela Pellegrino +1 位作者 Giuseppe Francesco Sferrazza Papa Riccardo Pellegrino 《World Journal of Respirology》 2014年第3期19-25,共7页
Spirometry is one of the functional tests most used in respiratory medicine to assess lung function in health and disease conditions.Its success is grounded on solid principles of lung mechanics that state that maxima... Spirometry is one of the functional tests most used in respiratory medicine to assess lung function in health and disease conditions.Its success is grounded on solid principles of lung mechanics that state that maximal flow on expiration is limited by the physical properties of airways and lung parenchyma.In contrast,on inspiration,flow depends on the force generated by the inspiratory muscles.Reduced expiratory forced flow and volumes usually reflect a deviation from health conditions.Yet due to a complex interplay of different obstructive and restrictive lung diseases within the multiple structural dimensions of the respiratory system,flows and volumes do not always perfectly reflect the impact of the disease on lung function.The present review is intended to shed light on a series of artefacts and biological phenomena that may confound the clinical interpretation of the main spirometric measurements.Among them is thoracic gas compression volume,the volume and time history of the inspiratory manoeuvre that precedes the forced expiration,the effects of heterogeneous distribution of the disease across the respiratory system,and the changes in lung elastic recoil. 展开更多
关键词 SPIROMETRY Thoracic gas compression VOLUME VOLUME HISTORY EFFECTS of the deep breath Time HISTORY EFFECTS of the preceding inspiratory manoeuvre Ventilation HETEROGENEITIES Lung elastic RECOIL clinical interpretation
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The Chapman-Richards Distribution and its Relationship to the Generalized Beta
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作者 Jeffrey H.Gove Thomas B.Lynch Mark J.Ducey 《Forest Ecosystems》 SCIE CSCD 2019年第3期219-235,共17页
Background: The Chapman-Richards distribution is developed as a special case of the equilibrium solution to the McKendrick-Von Foerster equation. The Chapman-Richards distribution incorporates the vital rate assumptio... Background: The Chapman-Richards distribution is developed as a special case of the equilibrium solution to the McKendrick-Von Foerster equation. The Chapman-Richards distribution incorporates the vital rate assumptions of the Chapman-Richards growth function, constant mortality and recruitment into the mathematical form of the distribution. Therefore, unlike 'assumed' distribution models, it is intrinsically linked with the underlying vital rates for the forest area under consideration. Methods: It is shown that the Chapman-Richards distribution can be recast as a subset of the generalized beta distribution of the first kind, a rich family of assumed probability distribution models with known properties. These known properties for the generalized beta are then immediately available for the Chapman-Richards distribution, such as the form of the compatible basal area-size distribution. A simple two-stage procedure is proposed for the estimation of the model parameters and simulation experiments are conducted to validate the procedure for four different possible distribution shapes. Results: The simulations explore the efficacy of the two-stage estimation procedure;these cover the estimation of the growth equation and mortality-recruitment derives from the equilibrium assumption. The parameter estimates are shown to depend on both the sample size and the amount of noise imparted to the synthetic measurements. The results vary somewhat by distribution shape, with the smaller, noisier samples providing less reliable estimates of the vital rates and final distribution forms. Conclusions: The Chapman-Richards distribution in its original form, or recast as a generalized beta form, presents a potentially useful model integrating vital rates and stand diameters into a flexible family of resultant distributions shapes. The data requirements are modest, and parameter estimation is straightforward provided the minimal recommended sample sizes are obtained. 展开更多
关键词 Diameter distributionS Chapman-Richards growth Generalized BETA distribution of the first KIND Maximum LIKELIHOOD McKendrick-Von Foerster equation Physiologically structured population model Size-structured distributionS
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Identification and distribution of 13003 landslides in the northwest margin of Qinghai-Tibet Plateau based on human-computer interaction remote sensing interpretation
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作者 Wei Wang Yuan-dong Huang +8 位作者 Chong Xu Xiao-yi Shao Lei Li Li-ye Feng Hui-ran Gao Yu-long Cui Shuai Wu Zhi-qiang Yang Kai Ma 《China Geology》 CAS CSCD 2024年第2期171-187,共17页
The periphery of the Qinghai-Tibet Plateau is renowned for its susceptibility to landslides.However,the northwestern margin of this region,characterised by limited human activities and challenging transportation,remai... The periphery of the Qinghai-Tibet Plateau is renowned for its susceptibility to landslides.However,the northwestern margin of this region,characterised by limited human activities and challenging transportation,remains insufficiently explored concerning landslide occurrence and dispersion.With the planning and construction of the Xinjiang-Tibet Railway,a comprehensive investigation into disastrous landslides in this area is essential for effective disaster preparedness and mitigation strategies.By using the human-computer interaction interpretation approach,the authors established a landslide database encompassing 13003 landslides,collectively spanning an area of 3351.24 km^(2)(36°N-40°N,73°E-78°E).The database incorporates diverse topographical and environmental parameters,including regional elevation,slope angle,slope aspect,distance to faults,distance to roads,distance to rivers,annual precipitation,and stratum.The statistical characteristics of number and area of landslides,landslide number density(LND),and landslide area percentage(LAP)are analyzed.The authors found that a predominant concentration of landslide origins within high slope angle regions,with the highest incidence observed in intervals characterised by average slopes of 20°to 30°,maximum slope angle above 80°,along with orientations towards the north(N),northeast(NE),and southwest(SW).Additionally,elevations above 4.5 km,distance to rivers below 1 km,rainfall between 20-30 mm and 30-40 mm emerge as particularly susceptible to landslide development.The study area’s geological composition primarily comprises Mesozoic and Upper Paleozoic outcrops.Both fault and human engineering activities have different degrees of influence on landslide development.Furthermore,the significance of the landslide database,the relationship between landslide distribution and environmental factors,and the geometric and morphological characteristics of landslides are discussed.The landslide H/L ratios in the study area are mainly concentrated between 0.4 and 0.64.It means the landslides mobility in the region is relatively low,and the authors speculate that landslides in this region more possibly triggered by earthquakes or located in meizoseismal area. 展开更多
关键词 LANDSLIDES Human-computer interaction interpretation Landslide database Spatial distribution Earthquake RAINFALL Human engineering activity Qinghai-Tibet Plateau Geological hazards survey engineering
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Does progress in microfracture techniques necessarily translate into clinical effectiveness?
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作者 Sathish Muthu Vibhu Krishnan Viswanathan +1 位作者 Manoharan Sakthivel Mohammed Thabrez 《World Journal of Orthopedics》 2024年第3期266-284,共19页
BACKGROUND Multitudinous advancements have been made to the traditional microfracture(MFx)technique,which have involved delivery of various acellular 2nd generation MFx and cellular MFx-III components to the area of c... BACKGROUND Multitudinous advancements have been made to the traditional microfracture(MFx)technique,which have involved delivery of various acellular 2nd generation MFx and cellular MFx-III components to the area of cartilage defect.The relative benefits and pitfalls of these diverse modifications of MFx technique are still not widely understood.AIM To comparatively analyze the functional,radiological,and histological outcomes,and complications of various generations of MFx available for the treatment of cartilage defects.METHODS A systematic review was performed using PubMed,EMBASE,Web of Science,Cochrane,and Scopus.Patients of any age and sex with cartilage defects undergoing any form of MFx were considered for analysis.We included only randomized controlled trials(RCTs)reporting functional,radiological,histological outcomes or complications of various generations of MFx for the management of cartilage defects.Network meta-analysis(NMA)was conducted in Stata and Cochrane’s Confidence in NMA approach was utilized for appraisal of evidence.RESULTS Forty-four RCTs were included in the analysis with patients of mean age of 39.40(±9.46)years.Upon comparing the results of the other generations with MFX-I as a constant comparator,we noted a trend towards better pain control and functional outcome(KOOS,IKDC,and Cincinnati scores)at the end of 1-,2-,and 5-year time points with MFx-III,although the differences were not statistically significant(P>0.05).We also noted statistically significant Magnetic resonance observation of cartilage repair tissue score in the higher generations of microfracture(weighted mean difference:17.44,95%confidence interval:0.72,34.16,P=0.025;without significant heterogeneity)at 1 year.However,the difference was not maintained at 2 years.There was a trend towards better defect filling on MRI with the second and third generation MFx,although the difference was not statistically significant(P>0.05).CONCLUSION The higher generations of traditional MFx technique utilizing acellular and cellular components to augment its potential in the management of cartilage defects has shown only marginal improvement in the clinical and radiological outcomes. 展开更多
关键词 Cartilage injury MICROFRACTURE Mesenchymal stem cells Platelet-rich plasma Bone marrow aspiration concentrates clinical outcome Radiological outcome Meta-analysis Network meta-analysis
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鸭瘟病毒弱毒株在免疫雏鸭体内的分布和排毒规律 被引量:18
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作者 程安春 汪铭书 +8 位作者 刘菲 宋涌 袁桂萍 韩晓英 徐超 廖永洪 文明 周伟光 贾仁勇 《中国兽医学报》 CAS CSCD 北大核心 2005年第3期231-233,258,共4页
鸭瘟病毒(DPV)弱毒Cha株经皮下、口服和滴鼻3种途径免疫1日龄雏鸭,应用聚合酶链反应(PCR)检测了病毒在体内分布和排毒规律。Cha株免疫雏鸭后,对血液、心、肝、脾、肺、肾、十二指肠、直肠、法氏囊、胸腺、胰腺、延脑、大脑、小脑、舌、... 鸭瘟病毒(DPV)弱毒Cha株经皮下、口服和滴鼻3种途径免疫1日龄雏鸭,应用聚合酶链反应(PCR)检测了病毒在体内分布和排毒规律。Cha株免疫雏鸭后,对血液、心、肝、脾、肺、肾、十二指肠、直肠、法氏囊、胸腺、胰腺、延脑、大脑、小脑、舌、肌肉、骨髓、粪便和食道共19种组织PCR检测结果如下(1)皮下接种雏鸭后4h,即可在心、肝、脾、肾、法氏囊、胸腺、胰腺、延脑、大脑和小脑共10种组织中检出DPV的DNA;8h后,所有采取的组织器官均可检测到DPV的DNA。(2)口服接种雏鸭后4h,可在舌和食道中检测到DPV的DNA;8h后,可在心、肝、脾、肾、胸腺、胰腺、延脑、大脑、小脑、舌、食道和血液共12种组织器官中检出DPV的DNA。(3)滴鼻接种雏鸭后4h,未能在各种组织中检出DPV的DNA;8h后,可在心、肝、脾、肾、胸腺、延脑、大脑、小脑、舌、食道和血液共11种组织中检测到DPV的DNA。(4)在3种免疫途径中,检出时间最早和检出率最高的组织器官为肝脏、脑(大脑、小脑和延脑);3种途径免疫的鸭,从免疫后12h至21d均能从所有采集的组织中检测出DPVDNA。 展开更多
关键词 DNA DPV Cha PCR 便
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Control of the Dust Vertical Distribution over Western Africa by Convection and Scavenging
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作者 H.Senghor R.Pilon +7 位作者 B.Diallo J.Escribano F.Hourdin J.Y.Grandpeix O.Boucher M.Gueye A.T.Gaye E.Machu 《Journal of Atmospheric Science Research》 2024年第1期19-39,共21页
Saharan dust represents more than 50%of the total desert dust emitted around the globe and its radiative effect significantly affects the atmospheric circulation at a continental scale.Previous studies on dust vertica... Saharan dust represents more than 50%of the total desert dust emitted around the globe and its radiative effect significantly affects the atmospheric circulation at a continental scale.Previous studies on dust vertical distribution and the Saharan Air Layer(SAL)showed some shortcomings that could be attributed to imperfect representation of the effects of deep convection and scavenging.The authors investigate here the role of deep convective transport and scavenging on the vertical distribution of mineral dust over Western Africa.Using multi-year(2006-2010)simulations performed with the variable-resolution(zoomed)version of the LMDZ climate model.Simulations are compared with aerosol amounts recorded by the Aerosol Robotic Network(AERONET)and with vertical profiles of the Cloud-Aerosol Lidar with Orthogonal Polarization(CALIOP)measurements.LMDZ allows a thorough examination of the respective roles of deep convective transport,convective and stratiform scavenging,boundary layer transport,and advection processes on the vertical mineral dust distribution over Western Africa.The comparison of simulated dust Aerosol Optical Depth(AOD)and distribution with measurements suggest that scavenging in deep convection and subsequent re-evaporation of dusty rainfall in the lower troposphere are critical processes for explaining the vertical distribution of desert dust.These processes play a key role in maintaining a well-defined dust layer with a sharp transition at the top of the SAL and in establishing the seasonal cycle of dust distribution.This vertical distribution is further reshaped offshore in the Inter-Tropical Convergence Zone(ITCZ)over the Atlantic Ocean by marine boundary layer turbulent and convective transport and wet deposition at the surface. 展开更多
关键词 DUST Vertical distribution SAHARA SAHEL West Africa Climate model CONVECTION SCAVENGING ITCZ
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Constructing Large Scale Cohort for Clinical Study on Heart Failure with Electronic Health Record in Regional Healthcare Platform:Challenges and Strategies in Data Reuse 被引量:2
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作者 Daowen Liu Liqi Lei +1 位作者 Tong Ruan Ping He 《Chinese Medical Sciences Journal》 CAS CSCD 2019年第2期90-102,共13页
Regional healthcare platforms collect clinical data from hospitals in specific areas for the purpose of healthcare management.It is a common requirement to reuse the data for clinical research.However,we have to face ... Regional healthcare platforms collect clinical data from hospitals in specific areas for the purpose of healthcare management.It is a common requirement to reuse the data for clinical research.However,we have to face challenges like the inconsistence of terminology in electronic health records (EHR) and the complexities in data quality and data formats in regional healthcare platform.In this paper,we propose methodology and process on constructing large scale cohorts which forms the basis of causality and comparative effectiveness relationship in epidemiology.We firstly constructed a Chinese terminology knowledge graph to deal with the diversity of vocabularies on regional platform.Secondly,we built special disease case repositories (i.e.,heart failure repository) that utilize the graph to search the related patients and to normalize the data.Based on the requirements of the clinical research which aimed to explore the effectiveness of taking statin on 180-days readmission in patients with heart failure,we built a large-scale retrospective cohort with 29647 cases of heart failure patients from the heart failure repository.After the propensity score matching,the study group (n=6346) and the control group (n=6346) with parallel clinical characteristics were acquired.Logistic regression analysis showed that taking statins had a negative correlation with 180-days readmission in heart failure patients.This paper presents the workflow and application example of big data mining based on regional EHR data. 展开更多
关键词 electronic health RECORDS clinical terminology knowledge graph clinical special disease case REPOSITORY evaluation of data quality large scale COHORT study
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