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Output feedback control of pantograph–catenary system with adaptive estimation of catenary parameters

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Journal of Modern Transportation 2015年第4期23卷 252-261页

作者： E.Chater D.Ghani f.giri M.Haloua LAII Lab EMI Med V University UNICAEN GREYC Lab UMR CNRS Normandie Universite'

With the increasing railway vehicle speed, pantograph--catenary （PAC） system has become an important part as its incidents still stand among the prin- cipal causes of railway traffic interruption. Indeed, when a rail vehicle moves, the pantograph should constantly press against the underside of the catenary. Nonetheless, it is difficult to get around the complexity of the physical interaction between the pantograph and the contact wire, which could deteriorate the quality of the electricity transfer. Thus, PAC system performances could dramati- cally be reduced because of bad current collection. Therefore, in this paper, we present an output feedback solution in order to design an active control of PAC system. The proposed solution is based on the backstepping control and an adaptive observer that estimates both the （unknown） catenary parameters and the system state. All synthesis steps are given and the closed-loop analysis shows asymptotic tracking behavior regardless of the time-vary- ing catenary stiffness. furthermore, a numerical example shows that the PAC contact can be regulated with desired effect.

关键词： Transportation systems Periodic systemsanalysis Control of oscillations

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Advancements in medical treatment for pancreatic neuroendocrine tumors:A beacon of hope

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World Journal of Gastroenterology 2024年第12期30卷 1670-1675页

作者： Somdatta giri Jayaprakash Sahoo Department of Endocrinology and Metabolism Jawaharlal Institute of Postgraduate Medical Education and ResearchPuducherry605006India

This editorial highlights the remarkable advancements in medical treatment strategies for pancreatic neuroendocrine tumors(pan-NETs),emphasizing tailored approaches for specific subtypes.Cytoreductive surgery and somatostatin analogs(SSAs)play pivotal roles in managing tumors,while palliative options such as molecular targeted therapy,peptide receptor radionuclide therapy,and chemotherapy are reserved for SSA-refractory patients.Gastrinomas,insul-inomas,glucagonomas,carcinoid tumors and VIPomas necessitate distinct thera-peutic strategies.Understanding the genetic basis of pan-NETs and exploring immunotherapies could lead to promising avenues for future research.This review underscores the evolving landscape of pan-NET treatment,offering renewed hope and improved outcomes for patients facing this complex disease.

关键词： Pancreatic neuroendocrine tumor Medical management Somatostatin analog Immunotherapy Everolimus

Cracking the silent gallstone code:Wait or operate?

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World Journal of Clinical Cases 2024年第16期12卷 2692-2697页

作者： Aakansha giri Goswami Somprakas Basu Department of General Surgery All India Institute of Medical SciencesRishikesh 249203UttarakhandIndia

The widespread availability of abdominal ultrasound has revealed the common occurrence of asymptomatic gallstones.While the treatment for symptomatic gallstones is clear,the benefits of minimally invasive laparoscopic cholecystectomy have sparked debate about the best approach to managing silent gallstones.The potential for asymptomatic gallstones to become symptomatic or lead to complications complicates the decision-making process regarding surgical intervention,as it's uncertain when or which patients might develop complications.Consequently,risk stratification appears to play a critical role in guiding decisions about silent gallstones.However,there is no definitive evidence to direct management,and a consensus-based on high-quality evidence is yet to be established.

关键词： Asymptomatic gallstones Silent gallstones Cholecystectomy Gallbladder cancer Risk stratification

Prevalence and outcome of sarcopenia in non-alcoholic fatty liver disease

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World Journal of Gastrointestinal Pathophysiology 2024年第1期15卷 44-54页

作者： Suprabhat giri Prajna Anirvan Sumaswi Angadi Ankita Singh Anurag Lavekar Department of Gastroenterology and Hepatology Kalinga Institute of Medical SciencesBhubaneswar 751024OdishaIndia Department of Gastroenterology Kalinga Gastroenterology FoundationCuttack753001OdishaIndia Department of Gastroenterology Nizam’s Institute of Medical SciencesHyderabad 500082TelanganaIndia Department of Gastroenterology Seth GS Medical College and KEM HospitalMumbai 400012MaharashtraIndia Department of Gastroenterology Sagar HospitalBengaluru 560041KarnatakaIndia

BACKGROUND Nonalcoholic fatty liver disease(NAfLD)includes a spectrum of conditions,progressing from mild steatosis to advanced fibrosis.Sarcopenia,characterized by decreased muscle strength and mass,shares common pathophysiological traits with NAfLD.An association exists between sarcopenia and increased NAfLD prevalence.However,data on the prevalence of sarcopenia in NAfLD and its impact on the outcomes of NAfLD remain inconsistent.AIM To analyze the prevalence and outcomes of sarcopenia in patients with NAfLD.METHODS We conducted a comprehensive search for relevant studies in MEDLINE,Embase,and Scopus from their inception to June 2023.We included studies that focused on patients with NAfLD,reported the prevalence of sarcopenia as the primary outcome,and examined secondary outcomes,such as liver fibrosis and other adverse events.We also used the Newcastle-Ottawa scale for quality assessment.RESULTS Of the 29 studies included,the prevalence of sarcopenia in NAfLD varied widely(1.6%to 63.0%),with 20 studies reporting a prevalence of more than 10.0%.Substantial heterogeneity was noted in the measurement modalities for sarcopenia.Sarcopenia was associated with a higher risk of advanced fibrosis(odd ratio:1.97,95%confidence interval:1.44-2.70).Increased odds were consistently observed in fibrosis assessment through biopsy,NAfLD fibrosis score/body mass index,aspartate aminotransferase to alanine aminotransferase ratio,diabetes(BARD)score,and transient elastography,whereas the fibrosis-4 score showed no such association.Sarcopenia in NAfLD was associated with a higher risk of steatohepatitis,insulin resistance,cardiovascular risks,and mortality.CONCLUSION This systematic review highlights the critical need for standardized diagnostic criteria and measurement methods for sarcopenia in NAfLD patients.The variability in study designs and assessment methods for sarcopenia and liver fibrosis may account for the inconsistent findings.This review demonstrates the multidimensional impact of sarcopenia on NAfLD,indicating its

关键词： Non-alcoholic fatty liver disease Sarcopenia Hepatic fibrosis Low muscle mass Hand grip strength Bioelectric impedance analysis Dual X-ray absorptiometry

Probabilistic Analysis of Slope Using finite Element Approach and Limit Equilibrium Approach around Amalpata Landslide of West Central, Nepal

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International Journal of Geosciences 2024年第5期15卷 416-432页

作者： Mahendra Acharya Khomendra Bhandari Sandesh Dhakal Aasish giri Prabin Kafle Central Department of Geology Tribhuvan University Kathmandu Nepal Department of Geology Tri-Chandra Multiple Campus Tribhuvan University Kathmandu Nepal Sri Revana Siddeshwara Institute of Technology Visvesvaraya Technological University Bengaluru India

The stability study of the ongoing and recurring Amalpata landslide in Baglung in Nepal’s Gandaki Province is presented in this research. The impacted slope is around 200 meters high, with two terraces that have different slope inclinations. The lower bench, located above the basement, consistently fails and sets others up for failure. The fluctuating water level of the slope, which travels down the slope masses, exacerbates the slide problem. The majority of these rocks are Amalpata landslide area experiences several structural disruptions. The area’s stability must be evaluated in order to prevent and control more harm from occurring to the nearby agricultural land and people living along the slope. The slopes’ failures increase the damages of house existing in nearby area and the erosion of the slope. Two modeling techniques the finite element approach and the limit equilibrium method were used to simulate the slope. The findings show that, in every case, the terrace above the basement is where the majority of the stress is concentrated, with a safety factor of near unity. Using probabilistic slope stability analysis, the failure probability was predicted to be between 98.90% and 100%.

关键词： finite Element Approach Limit Equilibrium Method Slope factor of Safety

An unexpected cellular fountain of youth:platelets provide factors rejuvenating brain functions

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Signal Transduction and Targeted Therapy 2024年第1期9卷 16-18页

作者： Harald f.Langer Department of Cardiology AngiologyHaemostaseology and Medical Intensive CareUniversity Medical Centre MannheimMedical Faculty MannheimHeidelberg UniversityMannheimGermany German Centre for Cardiovascular Research(DZHK) Partner Site Heidelberg/MannheimMannheimGermany European Center for Angioscience Medical Faculty MannheimHeidelberg UniversityMannheimGermany Cardiovascular systems biology Medical Clinic IUniversity Heart Center LübeckLübeckGermany

In a recent manuscript published in Nature,Schroer et al.discovered that platelets and in particular platelet derived Pf-4(CXCL4)are a novel factor,which can rejuvenate the mammalian neuronal system.1 These findings have the potential to trigger an entire new field of research opening new platelet-derived candidate effector molecules for supporting regeneration.

关键词： supporting platelets finding

Premature axon-oligodendrocyte interaction contributes to stalling of experimental axon regeneration after injury to the white matter

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Neural Regeneration Research 2024年第3期19卷 469-470页

作者： Ephraim f.Trakhtenberg Department of Neuroscience University of Connecticut School of MedicineFarmingtonCTUSA

Studies from nearly 3 decades ago suggested that,in the central nervous system(CNS),myelination of axons by oligodendrocytes not only helps improve axonal conductivity but also stabilizes circuitry(Colello and Schwab,1994).Over the years,myelin sheaths produced by oligodendrocytes have been found to contain multiple molecules that are inhibitory to axonal growth(e.g.,MAG,NogoA,OMgp,Semaphorins)(Yiu and He,2006;Silver et al.,2014).After white matter injury in the adult CNS,myelin debris from damaged axons and dead oligodendrocytes accumulates in the forming glial scar and exposes these myelin-associated axon growth-inhibitory molecules to the injured axonal stumps,thereby contributing to the inhibition of axonal regrowth.During development,CNS axons reach their postsynaptic targets and stop growing before oligodendrocytes appear and myelinate them(foran and Peterson,1992;Dangata et al.,1996).Therefore,myelin-associated axon growth-inhibitory molecules interacting with already grown axons during myelination were thought to block axons from promiscuous sprouting and miswiring,thereby stabilizing neural circuitry in the CNS(Colello and Schwab,1994).

关键词： thereby white injury

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Cognition and movement in neurodegenerative disorders:a dynamic duo

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Neural Regeneration Research 2024年第10期19卷 2101-2102页

作者： Marit f.L.Ruitenberg Department of Health Medical and NeuropsychologyLeiden UniversityLeidenthe Netherlands Leiden Institute for Brain and Cognition Leidenthe Netherlands

People with neurodegenerative disorders often experience problems across a variety of functional domains,including cognition,movement,and psychosocial functioning.The classification of these disorders is based on the phenotypical manifestations that represent the most prominent clinical features.for example,Parkinson's disease and Huntington's disease are typically regarded as movement disorders,whereas Alzheimer's disease(AD) and other dementias are regarded as cognitive disorders.

关键词： disorders Huntington degenerative

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Bolstering integrity in environmental data science and machine learning requires understanding socioecological inequity

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frontiers of Environmental Science & Engineering 2024年第5期18卷 171-179页

作者： Joe f.Bozeman III School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA30332USA School of Public Policy Georgia Institute of TechnologyAtlantaGA30332USA

Socioecological inequity in environmental data science—such as inequities deriving from data-driven approaches and machine learning(ML)—are current issues subject to debate and evolution.There is growing consensus around embedding equity throughout all research and design domains—from inception to administration,while also addressing procedural,distributive,and recognitional factors.Yet,practically doing so may seem onerous or daunting to some.The current perspective helps to alleviate these types of concerns by providing substantiation for the connection between environmental data science and socioecological inequity,using the Systemic Equity framework,and provides the foundation for a paradigmatic shift toward normalizing the use of equity-centered approaches in environmental data science and ML settings.Bolstering the integrity of environmental data science and ML is just beginning from an equity-centered tool development and rigorous application standpoint.To this end,this perspective also provides relevant future directions and challenges by overviewing some meaningful tools and strategies—such as applying the Wells-Du Bois Protocol,employing fairness metrics,and systematically addressing irreproducibility;emerging needs and proposals—such as addressing data-proxy bias and supporting convergence research;and establishes a ten-step path forward.Afterall,the work that environmental scientists and engineers do ultimately affect the well-being of us all.

关键词： Equity Bias Machine Learning Data Science Justice Systemic Equity