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World Journal of Pediatrics 2024年第6期20卷 633-634页

作者： jon Izquierdo-Pujol Sara Moron-Lopez IrsiCaixa and Institute for Health Science Research Germans Trias i Pujol(IGTP) Can Ruti CampusBadalonaSpain Biomedicine doctoral programme Faculty of BiologyUniversity of BarcelonaBarcelonaSpain CIBERINFEC MadridSpain

The coronavirus disease-19(COVID-19)outbreak,caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),was declared a global pandemic in March *** has affected over 700 million people worldwide and resulted in almost 7 million deaths,equating to a 1%mortality *** present,the majority of COVID-19 cases are either asymptomatic or mild,typically resolving within two ***,between 1%and 10%of COVID-19 survivors do not fully recover and experience a post-viral syndrome referred to as"long COVID","post-acute COVID-19 syndrome"(PASC),or"post-COVID condition"(PCC).This post-viral syndrome affects both adult and pediatric ***,most of the studies published to date evaluate the adult population,leaving a gap in our understanding of its impact on children and adolescents.

关键词： acute mortality respiratory

High-temperature tribological performance of functionally graded Stellite 6/WC metal matrix composite coatings manufactured by laser-directed energy deposition

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Friction 2024年第3期12卷 522-538页

作者： Marta OSTOLAZA Alaitz ZABALA jon Inaki ARRIZUBIETA Iñigo LLAVORI Nagore OTEGI Aitzol LAMIKIZ Department of Mechanical Engineering University of the Basque Country UPV/EHUPlaza Torres Quevedo 1Bilbo 48013Spain Faculty of Engineering Mechanics and Industrial ProductionMondragon UnibertsitateaLoramendi 4Mondragon 20500Spain

Wear-driven tool failure is one of the main hurdles in the *** issue can be addressed through surface coating with ceramic-reinforced metal matrix ***,the maximum ceramic content is limited by *** this work,the tribological behaviour of the functionally graded WC-ceramic-particlereinforced Stellite 6 coatings is *** that end,the wear resistance at room temperature and 400°C is ***,the tribological analysis is supported by crack sensitivity and hardness evaluation,which is of utmost importance in the processing of composite materials with *** indicate that functionally graded materials can be employed to increase the maximum admissible WC content,hence improving the tribological behaviour,most notably at high ***,a shift from abrasive to oxidative wear is observed in high-temperature wear testing.

关键词： friction coating metal matrix composite functionally graded materials high temperature laserdirected energy deposition

Implications for brainstem recovery from studies in primates after sensory loss from arm

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Neural Regeneration Research 2024年第3期19卷 479-480页

作者： Jamie L.Reed Hui-Xin Qi jon H.Kaas Department of Psychology Vanderbilt UniversityNashvilleTNUSA

For decades,researchers have known that when neurons lose their activating inputs,they can atrophy and even *** example,removing sensory nerve inputs from the arm to the spinal cord after amputation or cutting the spinal nerves can shrink the post-synaptic target zones(e.g.,Woods et al.,2000).From touch receptors for the hand and arm,primary nerve afferents enter the spinal cord,and axons travel in the dorsal columns to target the cuneate nucleus(Cu)of the brainstem on the same side of the body(Figure 1).When sensory loss is unilateral,the overwhelming result is for the associated primary target zone to shrink in total size(cross-sectional area),as compared to the size of the opposite side.

关键词： brainstem shrink removing

A simple modification to the classical SIR model to estimate the proportion of under-reported infections using case studies in flu and COVID-19

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Infectious Disease Modelling 2024年第4期9卷 1147-1162页

作者： Leonid Kalachev jon Graham Erin L.Landguth Mathematical Sciences University of MontanaMissoulaUSA Center for Population Health Research School of Public and Community Health SciencesUniversity of MontanaMissoulaUSA

Background:Under-reporting and,thus,uncertainty around the true incidence of health events is common in all public health reporting *** the problem of underreporting is acknowledged in epidemiology,the guidance and methods available for assessing and correcting the resulting bias are ***:We aim to design a simple modification to the Susceptible e Infected e Removed(SIR)model for estimating the fraction or proportion of reported infection ***:The suggested modification involves rescaling of the classical SIR model producing its mathematically equivalent version with explicit dependence on the reporting parameter(true proportion of cases reported).We justify the rescaling using the phase plane analysis of the SIR model system and show how this rescaling parameter can be estimated from the data along with the other model ***:We demonstrate how the proposed method is cross-validated using simulated data with known disease cases and then apply it to two empirical reported data sets to estimate the fraction of reported cases in Missoula County,Montana,USA,using:(1)flu data for 2016e2017 and(2)COVID-19 data for fall of ***:We establish with the simulated and COVID-19 data that when most of the disease cases are presumed reported,the value of the additional reporting parameter in the modified SIR model is close or equal to one,so that the original SIR model is appropriate for data ***,the flu example shows that when the reporting parameter is close to zero,the original SIR model is not accurately estimating the usual rate parameters,and the re-scaled SIR model should be *** research demonstrates the role of under-reporting of disease data and the importance of accounting for underreporting when modeling simulated,endemic,and pandemic disease *** reporting the“true”number of disease cases will have downstream impacts on predictions of disease dynamics.A simple parameter adjustment

关键词： Modeling of epidemics SIR type models flu and COVID-19 Under-reporting parameter Proportion of reported disease cases

Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems

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Journal of Mountain Science 2024年第1期21卷 33-48页

作者： Francis Levi A.DURANO jon Marx SARMIENTO Larry N.DIGAL Pedro A.ALVIOLA IV School of Management University of the Philippines MindanaoDavao City 8000Philippines

Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation

关键词： Cocoa farms Cobb-Douglas production function Elevation Philippines Stochastic frontier analysis Technical efficiency

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这不是世界末日

网球大师 2008年第8期 20-20页

作者： jon wertheim 《体育画报》

费德勒上周在多伦多首轮输给西蒙,进一步论证了一个事实:千真万确,费氏王朝正在衰退。很不幸,我不得不承认那场比赛说明了不少问题:a)他还没有从温网决赛失利的余震中走出:b)他感到疲惫:c)在决胜盘遭到破发,输给一个二流球手,说明他的... 详细信息

费德勒上周在多伦多首轮输给西蒙,进一步论证了一个事实:千真万确,费氏王朝正在衰退。很不幸,我不得不承认那场比赛说明了不少问题:a)他还没有从温网决赛失利的余震中走出:b)他感到疲惫:c)在决胜盘遭到破发,输给一个二流球手,说明他的自信不足,绝没达到球王应有的标准。

关键词：世界末日

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奥运该欢迎网球吗?

网球大师 2008年第9期 18-18页

作者： jon wertheim 《体育画报》

我曾说网球被纳入奥运会是个错误,现在我发现自己肯定属于少数派,但我仍然认为奥运网球没多大意义。这并不是丑陋的美国主义,也不是因为奥运会破坏了美网系列赛的完整性。对于一个在奥运会中的项目,金牌应该体现该运动的巅峰,是对运动... 详细信息

我曾说网球被纳入奥运会是个错误,现在我发现自己肯定属于少数派,但我仍然认为奥运网球没多大意义。这并不是丑陋的美国主义,也不是因为奥运会破坏了美网系列赛的完整性。对于一个在奥运会中的项目,金牌应该体现该运动的巅峰,是对运动员成就的最高肯定。而在网球世界,奥运会甚至排不上前四,显然四大满贯的重要性都在奥运会之前。

关键词：奥运会网球比赛奥运村跳水运动员选手篮球美国主义肯定北京特殊价值

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莎拉波娃不是WTA的花瓶

新体育 2008年第3期 57-57页

作者： jon wertheim

上帝公平吗？在苏拉波娃拿到她的第三个大满贯之前，答案是肯定的。至少在很多人心里，老天还是先知先觉的。可是，当莎拉波娃在墨尔本拿到个人第三个大满贯冠军后，还有人会认为这个世界公平吗？当美貌、天赋、荣耀、金钱、冠军，这所... 详细信息

上帝公平吗？在苏拉波娃拿到她的第三个大满贯之前，答案是肯定的。至少在很多人心里，老天还是先知先觉的。可是，当莎拉波娃在墨尔本拿到个人第三个大满贯冠军后，还有人会认为这个世界公平吗？当美貌、天赋、荣耀、金钱、冠军，这所有的一切都被一个人揽于一身时，你所能做的只有一声叹息。

关键词：花瓶大满贯墨尔本公平冠军个人

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决战多哈

网球大师 2008年第12期 17-17页

作者： jon wertheim otonal 《体育画报》

在我看来,WTA在几年前曾面临一个抉择。他们可以把年终总决赛放在一个有着巨大受众群的市场,投资市场或推广,然后让它成为女子网球和顶尖选手的展示舞台。(纽约是理想地点.

关键词：多哈总决赛女子海宁年终男女平等投资市场网球文化受众投资人

Batch Active Learning for Multispectral and Hyperspectral Image Segmentation Using Similarity Graphs

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1013-1033页

作者： Bohan Chen Kevin Miller Andrea L.Bertozzi jon Schwenk Department of Mathematics University of CaliforniaLos Angeles520 Portola PlazaLosAngeles90095CAUSA Oden Institute for Computational Engineering and Sciences University of Texas at Austin201 E 24th StAustin 78712TXUSA Los Alamos National Laboratory Los AlamosNM 87545USA

Graph learning,when used as a semi-supervised learning(SSL)method,performs well for classification tasks with a low label *** provide a graph-based batch active learning pipeline for pixel/patch neighborhood multi-or hyperspectral image *** batch active learning approach selects a collection of unlabeled pixels that satisfy a graph local maximum constraint for the active learning acquisition function that determines the relative importance of each pixel to the *** work builds on recent advances in the design of novel active learning acquisition functions(e.g.,the Model Change approach in arXiv:2110.07739)while adding important further developments including patch-neighborhood image analysis and batch active learning methods to further increase the accuracy and greatly increase the computational efficiency of these *** addition to improvements in the accuracy,our approach can greatly reduce the number of labeled pixels needed to achieve the same level of the accuracy based on randomly selected labeled pixels.

关键词： Image segmentation Graph learning Batch active learning Hyperspectral image