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Hybrid Scalable Researcher Recommendation System Using Azure Data Lake Analytics
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作者 Dinesh Kalla Nathan Smith +1 位作者 Fnu Samaah Kiran Polimetla 《Journal of Data Analysis and Information Processing》 2024年第1期76-88,共13页
This research paper has provided the methodology and design for implementing the hybrid author recommender system using Azure Data Lake Analytics and Power BI. It offers a recommendation for the top 1000 Authors of co... This research paper has provided the methodology and design for implementing the hybrid author recommender system using Azure Data Lake Analytics and Power BI. It offers a recommendation for the top 1000 Authors of computer science in different fields of study. The technique used in this paper is handling the inadequate Information for citation;it removes the problem of cold start, which is encountered by very many other recommender systems. In this paper, abstracts, the titles, and the Microsoft academic graphs have been used in coming up with the recommendation list for every document, which is used to combine the content-based approaches and the co-citations. Prioritization and the blending of every technique have been allowed by the tuning system parameters, allowing for the authority in results of recommendation versus the paper novelty. In the end, we do observe that there is a direct correlation between the similarity rankings that have been produced by the system and the scores of the participant. The results coming from the associated scrips of analysis and the user survey have been made available through the recommendation system. Managers must gain the required expertise to fully utilize the benefits that come with business intelligence systems [1]. Data mining has become an important tool for managers that provides insights about their daily operations and leverage the information provided by decision support systems to improve customer relationships [2]. Additionally, managers require business intelligence systems that can rank the output in the order of priority. Ranking algorithm can replace the traditional data mining algorithms that will be discussed in-depth in the literature review [3]. 展开更多
关键词 Azure Data Lake U-SQL Author Recommendation System Power BI Microsoft Academic Big Data Word Embedding
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Ability of lactulose breath test results to accurately identify colorectal polyps through the measurement of small intestine bacterial overgrowth 被引量:1
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作者 Lan Li Xue-Yuan Zhang +5 位作者 Jin-Sheng Yu Hui-Min Zhou Yan Qin Wen-Rui Xie Wen-Jing Ding Xing-Xiang He 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第6期1138-1148,共11页
BACKGROUND While colorectal polyps are not cancerous,some types of polyps,known as adenomas,can develop into colorectal cancer over time.Polyps can often be found and removed by colonoscopy;however,this is an invasive... BACKGROUND While colorectal polyps are not cancerous,some types of polyps,known as adenomas,can develop into colorectal cancer over time.Polyps can often be found and removed by colonoscopy;however,this is an invasive and expensive test.Thus,there is a need for new methods of screening patients at high risk of developing polyps.AIM To identify a potential association between colorectal polyps and small intestine bacteria overgrowth(SIBO)or other relevant factors in a patient cohort with lactulose breath test(LBT)results.METHODS A total of 382 patients who had received an LBT were classified into polyp and non-polyp groups that were confirmed by colonoscopy and pathology.SIBO was diagnosed by measuring LBTderived hydrogen(H)and methane(M)levels according to 2017 North American Consensus recommendations.Logistic regression was used to assess the ability of LBT to predict colorectal polyps.Intestinal barrier function damage(IBFD)was determined by blood assays.RESULTS H and M levels revealed that the prevalence of SIBO was significantly higher in the polyp group than in the non-polyp group(41%vs 23%,P<0.01;71%vs 59%,P<0.05,respectively).Within 90 min of lactulose ingestion,the peak H values in the adenomatous and inflammatory/hyperplastic polyp patients were significantly higher than those in the non-polyp group(P<0.01,and P=0.03,respectively).In 227 patients with SIBO defined by combining H and M values,the rate of IBFD determined by blood lipopolysaccharide levels was significantly higher among patients with polyps than those without(15%vs 5%,P<0.05).In regression analysis with age and gender adjustment,colorectal polyps were most accurately predicted with models using M peak values or combined H and M values limited by North American Consensus recommendations for SIBO.These models had a sensitivity of≥0.67,a specificity of≥0.64,and an accuracy of≥0.66.CONCLUSION The current study made key associations among colorectal polyps,SIBO,and IBFD and demonstrated that LBT has moderate potential as an alternative noninvasive screening tool for colorectal polyps. 展开更多
关键词 Lactulose breath test Colorectal polyp Small intestine bacteria overgrowth Intestinal barrier function Retrospective study
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Review of the prevalence,diagnostics,and containment measures of the current mpox outbreak
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作者 Adekunle Sanyaolu Aleksandra Marinkovic +6 位作者 Chuku Okorie Stephanie Prakash Nafees Haider Yashika Dixon Ricardo Izurieta Olanrewaju Badaru Stella Smith 《World Journal of Clinical Cases》 SCIE 2023年第6期1252-1260,共9页
Monkeypox(mpox),is a disease from the Poxviridae family that can cause several serious medical issues.This mini-review sought to analyze the existing literature regarding the current mpox outbreak with a focus on the ... Monkeypox(mpox),is a disease from the Poxviridae family that can cause several serious medical issues.This mini-review sought to analyze the existing literature regarding the current mpox outbreak with a focus on the prevalence,diagnostics,and containment measures.Mpox cases have been reported to World Health Organization(WHO)from 85 Member States in all six WHO regions during the period of January 1,2022,through August 3,2022.Standardized or optimized guidelines for the clinical care of patients with mpox are limited,particularly in low-resource settings.In an effort to achieve guidance and meet standards,special attention should be paid to this outbreak in order to eradicate such a rare infectious disease by analyzing prevention and control measures.Patient outcomes may also be poor,and their illnesses may last for a long time.The spectrum of clinical symptoms,including complications and sequelae,as well as aspects of the illness may be indicators of sickness severity and complications;therefore,its clinical presentation must be better understood to improve containment measures.In addition,it is important to create and evaluate a standard of care that takes a variety of parameters into account,including antiviral,immune therapies,and clinical metrics that are particular to mpox.The global emergence of mpox has presented new challenges for public health and has called for further investigation into its epidemiological profile across international contexts. 展开更多
关键词 Monkeypox virus OUTBREAK PREVALENCE CONTAINMENT EPIDEMIOLOGY ORTHOPOXVIRUS
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Acute appendicitis: Epidemiology, treatment and outcomesanalysis of 16544 consecutive cases 被引量:15
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作者 Marco Ceresoli Alberto Zucchi +7 位作者 Niccolò Allievi Asaf Harbi Michele Pisano Giulia Montori Arianna Heyer Gabriela E Nita Luca Ansaloni Federico Coccolini 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2016年第10期693-699,共7页
AIM To investigate the epidemiology,treatment and outcomes of acute appendicitis(AA) in a large population study.METHODS This is a retrospective cohort study derived from the administrative dataset of the Bergamo dist... AIM To investigate the epidemiology,treatment and outcomes of acute appendicitis(AA) in a large population study.METHODS This is a retrospective cohort study derived from the administrative dataset of the Bergamo district healthcare system(more than 1 million inhabitants) from 1997 to 2013.Data about treatment,surgery,length of stay were collected.Moreover for each patients were registered data about relapse of appendicitis and hospital admission due to intestinal obstruction.RESULTS From 1997 to 2013 in the Bergamo district we collected 16544 cases of AA,with a crude incidence rate of 89/100000 inhabitants per year; mean age was 24.51 ± 16.17,54.7% were male and the mean Charlson's comorbidity index was 0.32 ± 0.92.Mortality was < 0.0001%.Appendectomy was performed in 94.7% of the patients and the mean length of stay was 5.08 ± 2.88 d; the cumulative hospital stay was 5.19 ± 3.36 d and 1.2% of patients had at least one further hospitalization due intestinal occlusion.Laparoscopic appendectomy was performed in 48% of cases.Percent of 5.34 the patients were treated conservatively with a mean length of stay of 3.98 ± 3.96 d; the relapse rate was 23.1% and the cumulative hospital stay during the study period was 5.46 ± 6.05 d.CONCLUSION The treatment of acute appendicitis in Northern Italy is slowly changing,with the large diffusion of laparoscopic approach; conservative treatment of non-complicated appendicitis is still a neglected option,but rich of promising results. 展开更多
关键词 Acute APPENDICITIS CONSERVATIVE TREATMENT EPIDEMIOLOGY Laparoscopic APPENDECTOMY Intestinal OBSTRUCTION
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Improved RBF network application in analog circuit fault isolation 被引量:1
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作者 禹航 肖明清 赵鑫 《Journal of Measurement Science and Instrumentation》 CAS 2012年第1期70-74,共5页
One kind of steepest descent incremental projection learning algorithm for improving the training of radial basis function(RBF)neural network is proposed,which is applied to analog circuit fault isolation.This algorit... One kind of steepest descent incremental projection learning algorithm for improving the training of radial basis function(RBF)neural network is proposed,which is applied to analog circuit fault isolation.This algorithm simplified the structure of network through optimum output layer coefficient with incremental projection learning(IPL)algorithm,and adjusted the parameters of the neural activation function to control the network scale and improve the network approximation ability.Compared to the traditional algorithm,the improved algorithm has quicker convergence rate and higher isolation precision.Simulation results show that this improved RBF network has much better performance,which can be used in analog circuit fault isolation field. 展开更多
关键词 analog circuit fault isolation RBF network IPL algorithm steepest descent algorithm
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COVID-19 and gut immunomodulation 被引量:2
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作者 Koushik Roy Sidra Agarwal +2 位作者 Rajib Banerjee Manash K Paul Prabhat K Purbey 《World Journal of Gastroenterology》 SCIE CAS 2021年第46期7925-7942,共18页
The disease coronavirus disease 2019(COVID-19)is a severe respiratory illness that has emerged as a devastating health problem worldwide.The disease outcome is heterogeneous,and severity is likely dependent on the imm... The disease coronavirus disease 2019(COVID-19)is a severe respiratory illness that has emerged as a devastating health problem worldwide.The disease outcome is heterogeneous,and severity is likely dependent on the immunity of infected individuals and comorbidities.Although symptoms of the disease are primarily associated with respiratory problems,additional infection or failure of other vital organs are being reported.Emerging reports suggest a quite common co-existence of gastrointestinal(GI)tract symptoms in addition to respiratory symptoms in many COVID-19 patients,and some patients show just the GI symptoms.The possible cause of the GI symptoms could be due to direct infection of the epithelial cells of the gut,which is supported by the fact that(1)The intestinal epithelium expresses a high level of angiotensin-converting enzyme-2 and transmembrane protease serine 2 protein that are required for the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)entry into the cells;(2)About half of the severe COVID-19 patients show viral RNA in their feces and various parts of the GI tract;and(3)SARS-CoV-2 can directly infect gut epithelial cells in vitro(gut epithelial cells and organoids)and in vivo(rhesus monkey).The GI tract seems to be a site of active innate and adaptive immune responses to SARS-CoV-2 as clinically,stool samples of COVID-19 patients possess proinflammatory cytokines(interleukin 8),calprotectin(neutrophils activity),and immunoglobulin A antibodies.In addition to direct immune activation by the virus,impairment of GI epithelium integrity can evoke immune response under the influence of systemic cytokines,hypoxia,and changes in gut microbiota(dysbiosis)due to infection of the respiratory system,which is confirmed by the observation that not all of the GI symptomatic patients are viral RNA positive.This review comprehensively summarizes the possible GI immunomodulation by SARS-CoV-2 that could lead to GI symptoms,their association with disease severity,and potential therapeutic interventions. 展开更多
关键词 COVID-19 Gastrointestinal symptoms PATHOGENESIS Innate immune response Adaptive immune response Gut microbiota DYSBIOSIS THERAPEUTICS Probiotic Pre-existing diseases
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EUS引导下的Trucut针吸活检:确定自身免疫性胰腺炎是否为梗阻性黄疽的病因 被引量:2
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作者 Levy M.J Reddy R.P +1 位作者 Wiersema M.J 陈云茹 《世界核心医学期刊文摘(胃肠病学分册)》 2005年第8期37-37,共1页
Background: The diagnosis of autoimmune pancreatitis can be difficult and ofte n requires a larger specimen than can be provided by FNA alone to determine if t he tissue sample obtained with EUS trucut biopsy (TCB) is... Background: The diagnosis of autoimmune pancreatitis can be difficult and ofte n requires a larger specimen than can be provided by FNA alone to determine if t he tissue sample obtained with EUS trucut biopsy (TCB) is sufficient to allow ad equate histologic review to establish the diagnosis of autoimmune pancreatitis. Methods: EUS TCB was performed in patients presenting with obstructive jaundice who were suspected of having autoimmune pancreatitis based on their clinical, la boratory and imaging studies. The charts were retrospectively reviewed to determ ine the feasibility of TCB. Results: Between August 2002 and June 2004, 3 patien ts with obstructive jaundice and suspected autoimmune pancreatitis (AIP) underwe nt EUS TCB. In each case, a diagnosis of pancreatic cancer also was considered, and surgical resection was the planned therapy before the patient underwent EUS TCB. Histologic review of the TCB specimens established the diagnosis of AIP in two patients and identified nonspecific changes of chronic pancreatitis in the t hird patient. EUS-guided FNA was performed in two of the 3 patients and failed to establish the diagnosis in either patient. Other than mild transient abdomina l pain (n = 1), no complications were identified. Conclusions: This preliminary study suggests that EUS TCB can safely establish the diagnosis of AIP. Doing so helps guide management and may help to avoid unnecessary surgery. Prosp- ective studies are needed to verify these findings and to more clearly define the role of EUS TCB in these patients. 展开更多
关键词 EUS Trucut 针吸活检 阻性 黄疽 慢性胰腺炎 黄疸者 梗阻型 影像学检查 疑似患者
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Fault injection system for automatic testing system 被引量:1
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作者 王胜文 洪炳熔 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第3期321-324,共4页
Considering the deficiency of the means for confirming the attribution of fault redundancy in the re-search of Automatic Testing System(ATS) , a fault-injection system has been proposed to study fault redundancyof aut... Considering the deficiency of the means for confirming the attribution of fault redundancy in the re-search of Automatic Testing System(ATS) , a fault-injection system has been proposed to study fault redundancyof automatic testing system through compurison. By means of a fault-imbeded environmental simulation, thefaults injected at the input level of the software are under test. These faults may induce inherent failure mode,thus bringing about unexpected output, and the anticipated goal of the test is attained. The fault injection con-sists of voltage signal generator, current signal generator and rear drive circuit which are specially developed,and the ATS can work regularly by means of software simulation. The experimental results indicate that the faultinjection system can find the deficiency of the automatic testing software, and identify the preference of fault re-dundancy. On the other hand, some soft deficiency never exposed before can be identified by analyzing the tes-ting results. 展开更多
关键词 Fault injection comparing method rear drive ATS
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社区人群心力衰竭发病率及存活率的变化趋势 被引量:1
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作者 Roger V.L. Weston S.A. +1 位作者 Redfield M.M. 姜馨 《世界核心医学期刊文摘(心脏病学分册)》 2005年第1期7-8,共2页
Context: The epidemic of heart failure has yet to be fully investigated , and d ata on incidence, survival, and sexspecific temporal trends in community-based populations are limited. Objective: To test the hypothesis... Context: The epidemic of heart failure has yet to be fully investigated , and d ata on incidence, survival, and sexspecific temporal trends in community-based populations are limited. Objective: To test the hypothesis that the incidence of heart failure has declined and survival after heart failure diagnosis has improved over time but that secular trends have diverged by sex. Design, Setting, and Participants: Population-based cohort study using the resources of the Rochester Epidemiology Project conducted in Olmsted County , Minnesota. Patients were 4537 Olmsted County residents (57%women; mean <<SD>> a ge, 74 <<14>> years) with a diagnosis of heart failure between 1979 and 2000. Fram ingham criteria and clinical criteria were used to validate the diagnosis Main O utcome Measures: Incidence of heart failure and survival after heart failure dia gnosis. Results: The incidence of heart failure was higher among men (378/100000 persons; 95%confidence interval <<CI>>, 361-395 for men; 289/100000 persons; 95 %CI, 277-300 for women) and did not change over time among men or women. After a mean follow-up of 4.2 years (range, 0-23.8 years), 3347 deaths occurred, in cluding 1930 among women and 1417 among men. Survival after heart failure diagno sis was worse among men than women (relative risk, 1.33; 95%CI, 1.24-1.43) but overall improved over time (5-year age-adjusted survival, 43%in 1979-1984 v s 52%in 1996-2000, P< .001). However, men and younger persons experienced larg er survival gains, contrasting with less or no improvement for women and elderly persons. Conclusion: In this community-based cohort, the incidence of heart fa ilure has not declined during 2 decades, but survival after onset of heart failu re has increased overall, with less improvement among women and elderly persons. 展开更多
关键词 ROCHESTER 临床标准 性别差异 队列研究 明尼苏达州
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Chinese Patent, A Tentative Explanation of Various Strategies of Patenting
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作者 Dou Henri Dou Jean-Marie Jr 《Chinese Business Review》 2013年第1期41-47,共7页
The recent increase in patent granted in China prompts for an analysis of the various strategies which are certainly developed by Chinese applicants in that field. An analysis (APA Automatic Patent Analysis) has bee... The recent increase in patent granted in China prompts for an analysis of the various strategies which are certainly developed by Chinese applicants in that field. An analysis (APA Automatic Patent Analysis) has been done in several fields which have different impacts on the Chinese economy. We chose four different subjects: solar panels; photovoltaic panels; fireworks; and honeysuckle. These areas go from deep international concern to only Chinese interest. We analyzed in the different ratios between Chinese priority patents, Chinese patents extended to other countries, Patent extended from other countries to China and Chinese utility models. The results show clearly that various directions are followed depending on the economic importance of the field and also the pressure of the competition inside and outside China. In this context the strategic dependence (number of patents extended to China by other countries) was examined for each of the fields. We also show that in the domain where the man power is important such as fireworks the number of utility models is important. This suggests that utility models are used to spread in that field minor innovations. In the fields such as honeysuckle many applicants are the same that the inventors and the involvement of universities larger than in other fields. These two fields more or less centered on Chinese domestic aspects only a few patents (not for Honeysuckle) are extended to other countries. The impact of foreign patents in these two fields is quasi nil. In other domains such as photovoltaic panel the triadic patents (extension to US JP EP) are examined its show that if some Chinese patents are extended to other countries there are also an important numbers of foreign patents extended to China. This also suggests that in these most critical subjects, China develops a sort of technological protection barrier from domestic patents. This underlines a strategy on attack and defense in that field. 展开更多
关键词 automatic patent analysis FIREWORKS HONEYSUCKLE solar panel China strategic dependence
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One ring is sufficient to inhibit α-synuclein aggregation
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作者 Samuel Peña-Díaz Salvador Ventura 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第3期508-511,共4页
Parkinson's disease,the second most prevalent neurodegenerative disorder worldwide,is characterized by a progressive loss of dopaminergic neurons in substantia nigra pars compacta,causing motor symptoms.This disor... Parkinson's disease,the second most prevalent neurodegenerative disorder worldwide,is characterized by a progressive loss of dopaminergic neurons in substantia nigra pars compacta,causing motor symptoms.This disorder's main hallmark is the formation of intraneuronal protein inclusions,named Lewy bodies and neurites.The major component of these arrangements is α-synuclein,an intrinsically disordered and soluble protein that,in pathological conditions,can form toxic and cell-to-cell transmissible amyloid structures.Preventing α-synuclein aggregation has attracted significant effort in the search for a disease-modifying therapy for Parkinson's disease.Small molecules like Synu Clean-D,epigallocatechin gallate,trodusquemine,or anle138 b exemplify this therapeutic potential.Here,we describe a subset of compounds containing a single aromatic ring,like dopamine,ZPDm,gallic acid,or entacapone,which act as molecular chaperones against α-synuclein aggregation.The simplicity of their structures contrasts with the complexity of the aggregation process,yet the block efficiently α-synuclein assembly into amyloid fibrils,in many cases,redirecting the reaction towards the formation of non-toxic off-pathway oligomers.Moreover,some of these compounds can disentangle mature α-synuclein amyloid fibrils.Their simple structures allow structure-activity relationship analysis to elucidate the role of different functional groups in the inhibition of α-synuclein aggregation and fibril dismantling,making them informative lead scaffolds for the rational development of efficient drugs. 展开更多
关键词 amyloid aromatic rings dopamine inhibition NEURODEGENERATION OLIGOMERS Parkinson's disease protein aggregation Α-SYNUCLEIN
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Using density functional calculations to elucidate atomic ordering of Pd-Rh nanoparticles at sizes relevant for catalytic applications
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作者 Lorena Vega Hristiyan A.Aleksandrov Konstantin M.Neyman 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第11期1749-1757,共9页
Pd-Rh nanoparticles are known to easily undergo surface restructuring in reactive environment. This study quantifies, with the help of density functional(DFT) calculations and a novel topological approach, atomic orde... Pd-Rh nanoparticles are known to easily undergo surface restructuring in reactive environment. This study quantifies, with the help of density functional(DFT) calculations and a novel topological approach, atomic ordering and surface segregation effects in Pd-Rh particles with compositions 1:3, 1:1 and 3:1 containing up to 201 atoms(ca. 1.7 nm). The obtained data are used to reliably optimise energetically preferred atomic orderings in inaccessible by DFT Pd-Rh particles containing thousands of atoms and exhibiting sizes exceeding 5 nm, which are typical for catalytic metal particles. It is outlined, how segregation effects on the surface arrangement of Pd-Rh nanoalloy catalysts induced by adsorbates can be evaluated in a simple way within the present modelling setup. 展开更多
关键词 Density functional calculations Atomic ordering Pd Rh nanoparticles Size relevant
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功能性MRI可预测颞叶切除术后的记忆力
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作者 Rabin M.L. Narayan V.M. +2 位作者 Kimberg D.Y. J.A. Detre 杜芳 《世界核心医学期刊文摘(神经病学分册)》 2005年第3期32-33,共2页
Temporal lobectomy is an effective therapy for medically refractory temporal l obe epilepsy (TLE), but may be complicated by amnestic syndromes. Therefore, pre surgical evaluation to assess the risk/benefit ratio for ... Temporal lobectomy is an effective therapy for medically refractory temporal l obe epilepsy (TLE), but may be complicated by amnestic syndromes. Therefore, pre surgical evaluation to assess the risk/benefit ratio for surgery is required. Intracarotid amobarbital testing (IAT) is currently the most widely used method for assessing pre surgical memory lateralization, but is relatively invasive. O ver the past decade functional MRI (fMRI) has been shown to correlate with IAT f or language lateralization, and also for memory lateralization in a small number of patients. This study was carried out to compare fMRI during memory encoding with IAT testing for memory lateralization, and to asse ss the predictive value of fMRI during memory encoding for post surgical memory outcome. Thirty five patients with refractory TLE undergoing pre surgical eva luation for temporal lobectomy and 30 normal subjects performed a complex visual scene encoding task during fMRI scanning at 1.5 T using a 10 min protocol. En coding performance was evaluated with subsequent recognition testing. Twenty th ree patients also completed the same task again outside the scanner, an average of 6.9 months following surgery. A region of interest (ROI) analysis was used to quantify activation within hippocampal and a larger mesial temporal lobe ROI co nsisting of hippocampus, parahippocampus and fusiform gyrus (HPF) as defined by a published template. Normal subjects showed almost symmetrical activation with in these ROI. TLE patients showed greater asymmetry. Asymmetry ratios (ARs) from the HPF ROI correlated significantly with memory lateralization by intracarotid amobarbital testing. HPF ARs also correlated significantly with memory outcome, as determined by a change in scene recognition between pre surgical and post surgical trials. When absolute activation within the HPF ROI was considered, a s ignificant inverse correlation between activation ipsilateral to temporal lobect omy and memory outcome was observed, with no significant correlation in the cont ralateral HPF ROI. Although further technical improvements and prospective clini cal validation are required, these results suggest that mesial temporal memory a ctivation detected by fMRI during complex visual scene encoding correlates with post surgical memory outcome and supports the notion that this approach will ul timately contribute to patient management. 展开更多
关键词 颞叶切除术 记忆编码过程 药物难治性 优势侧 遗忘综合征 异戊巴比妥 颞叶癫痫 颈总动脉 预测价值 认知测验
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人类脊髓可整合迈步时的速度依赖性传导输入
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作者 Beres-Jones J.A. Harkema S.J. 陈云春 《世界核心医学期刊文摘(神经病学分册)》 2005年第3期29-29,共1页
We studied the motor response to modifying the rate of application of sensory input to the human spinal cord during stepping. We measured the electromyographi c (EMG), kinematic and kinetic patterns of the legs during... We studied the motor response to modifying the rate of application of sensory input to the human spinal cord during stepping. We measured the electromyographi c (EMG), kinematic and kinetic patterns of the legs during manually assisted or unassisted stepping using body weight support on a treadmill (BWST) in eight ind ividuals with spinal cord injury (SCI). At various treadmill speeds (0.27-1.52 m/s), we measured the EMG activity of the soleus (SOL), medial gastrocnemius (MG ), tibialis anterior (TA), medial hamstrings (MH), vastus lateralis (VL), rectus femoris (RF) and iliopsoas (ILIO); the hip, knee and ankle joint angles; the am ount of body weight support (BWS); and lower limb loading. The EMG amplitude and burst duration of the SOL, MG, TA, MH, VL, RF and ILIO were related to the step cycle duration during stepping using BWST. EMG mean amplitudes increased at fas ter treadmill speeds, and EMG burst durations shortened with decreased step cycl e durations. Muscle stretch of an individual muscle could not account for the EM G amplitude modulation in response to stepping speed. The effects on the EMG amp litude and burst duration were similar in subjects with partial and no detectabl e supraspinal input. We propose that the human spinal cord can interpret complex steprelated, velocity dependent afferent information to contribute to the neur al control of stepping. 展开更多
关键词 髂腰肌 脉冲持续时间 股外侧肌 股直肌 胫前肌 比目鱼肌 动力学模式 神经控制 关节角度 时可
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Metabolomic fingerprinting of pig seminal plasma identifies in vivo fertility biomarkers
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作者 Yentel Mateo-Otero Pol Fernández-López +5 位作者 Ariadna Delgado-Bermúdez Pau Nolis Jordi Roca Jordi Miró Isabel Barranco Marc Yeste 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2022年第2期473-487,共15页
Background:Metabolomic approaches,which include the study of low molecular weight molecules,are an emerging-omics technology useful for identification of biomarkers.In this field,nuclear magnetic resonance(NMR)spectro... Background:Metabolomic approaches,which include the study of low molecular weight molecules,are an emerging-omics technology useful for identification of biomarkers.In this field,nuclear magnetic resonance(NMR)spectroscopy has already been used to uncover(in)fertility biomarkers in the seminal plasma(SP)of several mammalian species.However,NMR studies profiling the porcine SP metabolome to uncover in vivo fertility biomarkers are yet to be carried out.Thus,this study aimed to evaluate the putative relationship between SPmetabolites and in vivo fertility outcomes.To this end,24 entire ejaculates(three ejaculates per boar)were collected from artificial insemination(AI)-boars throughout a year(one ejaculate every 4 months).Immediately after collection,ejaculates were centrifuged to obtain SP-samples,which were stored for subsequent metabolomic analysis by NMR spectroscopy.Fertility outcomes from 1525 inseminations were recorded over a year,including farrowing rate,litter size,stillbirths per litter and the duration of pregnancy.Results:A total of 24 metabolites were identified and quantified in all SP-samples.Receiver operating characteristic(ROC)curve analysis showed that lactate levels in SP had discriminative capacity for farrowing rate(area under the curve[AUC]=0.764)while carnitine(AUC=0.847),hypotaurine(AUC=0.819),sn-glycero-3-phosphocholine(AUC=0.833),glutamate(AUC=0.799)and glucose(AUC=0.750)showed it for litter size.Similarly,citrate(AUC=0.743),creatine(AUC=0.812),phenylalanine(AUC=0.750),tyrosine(AUC=0.753)and malonate(AUC=0.868)levels had discriminative capacity for stillbirths per litter;and malonate(AUC=0.767)and fumarate(AUC=0.868)levels for gestation length.Conclusions:The assessment of selected SP-metabolites in ejaculates through NMR spectroscopy could be considered as a promising non-invasive tool to predict in vivo fertility outcomes in pigs.Moreover,supplementing AI-doses with specific metabolites should also be envisaged as a way to improve their fertility potential. 展开更多
关键词 Artificial insemination in vivo fertility Metabolomics NMR Pregnancy outcomes Seminal plasma
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Radiative loss of coherence in free electrons:a long-range quantum phenomenon 被引量:1
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作者 Cruz I.Velasco Valerio Di Giulio F.Javier García de Abajo 《Light(Science & Applications)》 SCIE EI CSCD 2024年第2期294-301,共8页
Quantum physics rules the dynamics of small objects as they interact over microscopic length scales.Nevertheless,quantum correlations involving macroscopic distances can be observed between entangled photons as well a... Quantum physics rules the dynamics of small objects as they interact over microscopic length scales.Nevertheless,quantum correlations involving macroscopic distances can be observed between entangled photons as well as in atomic gases and matter waves at low temperatures.The long-range nature of the electromagnetic coupling between charged particles and extended objects could also trigger quantum phenomena over large distances.Here,we reveal a manifestation of quantum mechanics that involves macroscopic distances and results in a nearly complete depletion of coherence associated with which-way free-electron interference produced by electron-radiation coupling in the presence of distant extended objects.This is a ubiquitous effect that we illustrate through a rigorous theoretical analysis of a two-path electron beam interacting with a semi-infinite metallic plate and find the inter-path coherence to vanish proportionally to the path separation at zero temperature and exponentially at finite temperature.The investigated regime of large distances originates in the coupling of the electron to radiative modes assisted by diffraction at material structures but without any involvement of material excitations.Besides the fundamental interest of this macroscopic quantum phenomenon,our results suggest an approach to measuring the vacuum temperature and nondestructively sensing the presence of distant objects. 展开更多
关键词 temperature QUANTUM MACROSCOPIC
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Optimizing magneto-ionic performance in structure/composition-engineered ternary nitrides
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作者 Zheng Ma P.Monalisha +10 位作者 Zhengwei Tan Eva Pellicer Maciej O.Liedke Maik Butterling Ahmed G.Attallah Eric Hirschmann Andreas Wagner Fatima Ibrahim Mairbek Chshiev Enric Menndez Jordi Sort 《Journal of Materiomics》 SCIE CSCD 2024年第4期870-879,共10页
Magneto-ionics,an emerging approach to manipulate magnetism that relies on voltage-driven ion motion,holds the promise to boost energy efficiency in information technologies such as spintronic devices or future non-vo... Magneto-ionics,an emerging approach to manipulate magnetism that relies on voltage-driven ion motion,holds the promise to boost energy efficiency in information technologies such as spintronic devices or future non-von Neumann computing architectures.For this purpose,stability,reversibility,endurance,and ion motion rates need to be synergistically optimized.Among various ions,nitrogen has demonstrated superior magneto-ionic performance compared to classical species such as oxygen or lithium.Here,we show that ternary Co1−xFexN compound exhibits an unprecedented nitrogen magneto-ionic response.Partial substitution of Co by Fe in binary CoN is shown to be favorable in terms of generated magnetization,cyclability and ion motion rates.Specifically,the Co_(0.3)5Fe_(0.6)5N films exhibit an induced saturation magnetization of 1,500 emu/cm^(3),a magneto-ionic rate of 35.5 emu/(cm^(3)·s)and endurance exceeding 103 cycles.These values significantly surpass those of other existing nitride and oxide systems.This improvement can be attributed to the larger saturation magnetization of Co_(0.35)Fe_(0.65) compared to individual Co and Fe,the nature and size of structural defects in as-grown films of different composition,and the dissimilar formation energies of Fe and Co with N in the various developed crystallographic structures. 展开更多
关键词 Voltage control of magnetism Magneto-ionics Electrolyte gating Ternary nitrides Ion transport
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Machine learning applications on lunar meteorite minerals:From classification to mechanical properties prediction
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作者 Eloy Peña-Asensio Josep M.Trigo-Rodríguez +2 位作者 Jordi Sort Jordi Ibáñez-Insa Albert Rimola 《International Journal of Mining Science and Technology》 SCIE EI CAS 2024年第9期1283-1292,共10页
Amid the scarcity of lunar meteorites and the imperative to preserve their scientific value,nondestructive testing methods are essential.This translates into the application of microscale rock mechanics experiments ... Amid the scarcity of lunar meteorites and the imperative to preserve their scientific value,nondestructive testing methods are essential.This translates into the application of microscale rock mechanics experiments and scanning electron microscopy for surface composition analysis.This study explores the application of Machine Learning algorithms in predicting the mineralogical and mechanical properties of DHOFAR 1084,JAH 838,and NWA 11444 lunar meteorites based solely on their atomic percentage compositions.Leveraging a prior-data fitted network model,we achieved near-perfect classification scores for meteorites,mineral groups,and individual minerals.The regressor models,notably the KNeighbor model,provided an outstanding estimate of the mechanical properties—previously measured by nanoindentation tests—such as hardness,reduced Young’s modulus,and elastic recovery.Further considerations on the nature and physical properties of the minerals forming these meteorites,including porosity,crystal orientation,or shock degree,are essential for refining predictions.Our findings underscore the potential of Machine Learning in enhancing mineral identification and mechanical property estimation in lunar exploration,which pave the way for new advancements and quick assessments in extraterrestrial mineral mining,processing,and research. 展开更多
关键词 Meteorites Moon Mineralogy Machine learning Mechanical properties
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A PLS-SEM Based Approach: Analyzing Generation Z Purchase Intention Through Facebook’s Big Data
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作者 Vikas Kumar Preeti +5 位作者 Shaiku Shahida Saheb Sunil Kumari Kanishka Pathak Jai Kishan Chandel Neeraj Varshney Ankit Kumar 《Big Data Mining and Analytics》 EI CSCD 2023年第4期491-503,共13页
The objective of this paper is to provide a better rendition of Generation Z purchase intentions of retail products through Facebook.The study gyrated around the favorable attitude formation of Generation Z translatin... The objective of this paper is to provide a better rendition of Generation Z purchase intentions of retail products through Facebook.The study gyrated around the favorable attitude formation of Generation Z translating into intentions to purchase retail products through Facebook.The role of antecedents of attitude,namely enjoyment,credibility,and peer communication was also explored.The main purpose was to analyze the F-commerce pervasiveness(retail purchases through Facebook)among Generation Z in India and how could it be materialized effectively.A conceptual fac¸ade was proposed after trotting out germane and urbane literature.The study focused exclusively on Generation Z population.The data were statistically analyzed using partial least squares structural equation modelling.The study found the proposed conceptual model had a high prediction power of Generation Z intentions to purchase retail products through Facebook verifying the materialization of F-commerce.Enjoyment,credibility,and peer communication were proved to be good predictors of attitude(R^(2)=0.589)and furthermore attitude was found to be a stellar antecedent to purchase intentions(R^(2)=0.540). 展开更多
关键词 FACEBOOK ENJOYMENT CREDIBILITY peer communication ATTITUDE intentions to purchase
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High-Sensitivity Visualization of Ulitrafast Carrier Diffusion by Wide-Field Holographic Microscopy
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作者 Martin Hörmann Federico Visentin +6 位作者 Andrea Zanetta Johann Osmond Giulia Grancini Niek Fvan Hulst Matz Liebel Giulio Cerullo Franco V.A.Camargo 《Ultrafast Science》 2023年第5期43-49,共7页
Ultrafast transient microscopy is a key tool to study the photophysical properties of materials in space and time,but current implementations are limited to≈1-μm fields of view,offering no statistical information fo... Ultrafast transient microscopy is a key tool to study the photophysical properties of materials in space and time,but current implementations are limited to≈1-μm fields of view,offering no statistical information for heterogeneous samples.Recently,we demonstrated wide-field transient imaging based on multiplexed off-axis holography.Here,we perform ultrafast microscopy in parallel around a hundred diffraction-limited excitation spots over a≈60-μm field of view,which not only automatically samples the photophysical heterogeneity of the sample over a large area but can also be used to obtain a 10-fold increase in signal-tonoise ratio by computing an average spot.We apply our microscope to study the carrier diffusion processes in methylammonium lead bromide perovskites.We observe strong diffusion due to the presence of hot carriers during the first picosecond and slower diffusion afterward.We also describe how many-body kinetics can be misleadingly interpreted as strong diffusion at high excitation densities,while at weak excitation,real diffusion is observed.Therefore,the vast increase in sensitivity offered by this technique benefits the study of carrier transport not only by reducing data acquisition times but also by enabling the measurement of the much smaller signals generated at low carrier densities. 展开更多
关键词 DIFFUSION EXCITATION TRANSIENT
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