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改进A^(*)算法融合动态窗口法的无人船路径规划 被引量:1
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作者 党宽 黄红武 +1 位作者 高秀晶 辛鹏 《交通工程》 2025年第6期29-35,共7页
为让无人船具有正确的路径规划能力,并保证无人船能躲避实时障碍物到达目的地,提出一种结合改进A^(*)算法和改进动态窗口法的融合算法。首先,将A^(*)算法的8邻域搜索方向通过角度判断进行删减,减少路径搜索时间;其次,在A^(*)算法的估价... 为让无人船具有正确的路径规划能力,并保证无人船能躲避实时障碍物到达目的地,提出一种结合改进A^(*)算法和改进动态窗口法的融合算法。首先,将A^(*)算法的8邻域搜索方向通过角度判断进行删减,减少路径搜索时间;其次,在A^(*)算法的估价函数中引入人工势场算法进行路径修正,增加路径搜索的精确性,并通过节点斜率的关系,删除冗余路段。改进的A^(*)算法相比传统A^(*)算法在2个地图上路径分别缩短22.87%、4.54%,搜索时间分别减少57.66%、36.52%;接着,改进动态窗口法的评价函数,使无人船能更快到达目标点,改进的动态窗口法相比传统的动态窗口法在未知障碍物地图上搜索时间减少27.87%,路径长度减少3.78%;最后,把融合算法与其他算法比较,验证融合算法的实时避障能力。实验结果证明,融合算法规划的路径最短,能实时避障。 展开更多
关键词 无人船 改进A^(*)算法 改进动态窗口法 融合算法 实时避障
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某新建大型水电站发电量预测研究分析
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作者 王利宁 《现代工业经济和信息化》 2025年第4期262-264,共3页
水电是我国电力工业的重要组成部分,作为清洁能源在节能减排中扮演着重要角色。因此,通过对黄河上游某新建混流式机组水电站年来水量、月平均流量、在运水电站负荷率等历史数据计算分析,以在运同地区水电站近年负荷率进行复核,对预测结... 水电是我国电力工业的重要组成部分,作为清洁能源在节能减排中扮演着重要角色。因此,通过对黄河上游某新建混流式机组水电站年来水量、月平均流量、在运水电站负荷率等历史数据计算分析,以在运同地区水电站近年负荷率进行复核,对预测结果进行综合分析,最终得出本电站多年平均发电量预测结果。 展开更多
关键词 水电站 年发电量 综合分析
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金刚烷胺对海带幼孢子体的毒性研究
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作者 鹿瑶 徐英江 +6 位作者 赵军强 何金霞 刘辉 孙琰晴 王小涵 李晓捷 任利华 《水产学杂志》 2025年第5期52-60,78,共10页
金刚烷胺作为一种流感病毒的防治药物曾广泛应用于畜禽养殖中,过度使用导致其在环境中不断累积,且随地表径流最终汇入海洋,成为一种新型海洋污染物。研究表明:金刚烷胺对刺参等海洋生物具有一定的毒性效应,但对大型藻类的毒性效应研究... 金刚烷胺作为一种流感病毒的防治药物曾广泛应用于畜禽养殖中,过度使用导致其在环境中不断累积,且随地表径流最终汇入海洋,成为一种新型海洋污染物。研究表明:金刚烷胺对刺参等海洋生物具有一定的毒性效应,但对大型藻类的毒性效应研究十分有限。本文以大型褐藻海带的幼孢子体为研究对象,采用实验室内模拟的方式,系统研究了金刚烷胺对海带幼孢子体生长、生理结构、氧化损伤及抗氧化酶活性的影响。研究发现:金刚烷胺对海带幼孢子体具有生长抑制作用,损伤叶片组织结构;海带幼孢子体可以耐受低剂量(≤1.0×10^(4) ng·L^(-1))金刚烷胺的胁迫,氧化损伤可逆,但随暴露剂量增加,机体抗氧化系统被抑制,氧化损伤加剧乃至死亡。结果表明:金刚烷胺对海带幼孢子体的生长和抗氧化防御系统具有负面影响,对海洋生态系统的健康构成潜在威胁,急需加强对金刚烷胺的环境监测和管控,以减轻其对海洋生物的危害。 展开更多
关键词 金刚烷胺 海带幼孢子体 抗氧化系统 氧化损伤 组织切片
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Assessing the effectiveness of acoustic signals in mark-recapture studies to estimate dolphins population
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作者 Elena Papale Maria Ceraulo +2 位作者 Martina Gregoriettid Clarissa De Vita Giuseppa Buscaino 《Current Zoology》 2025年第4期409-418,共10页
Accurate estimations of animal population size are pivotal for implementing management strategies properly.Recapture technique based on sounds as a specimen identifcation mark has barely been used for marine mammals.H... Accurate estimations of animal population size are pivotal for implementing management strategies properly.Recapture technique based on sounds as a specimen identifcation mark has barely been used for marine mammals.However,inferring abundance estimates from acoustic methods could enhance the accuracy and precision of population size assessments.Here,we tested the possibility of using signature whistles as individual marks for estimating the size of common bottlenose dolphin(Tursiops truncatus)populations.Data were continuously collected for 326 days in 2015–2016,by using a fxed acoustic device located in the Sicily Strait(Italy).The SIGID method was applied to identify Signature Whistles Types(SWTs)over 7,000 h of recordings.Eighty SWTs were detected as long as their stereotyped fundamental frequency contours were repeated in bouts of at least 6 renditions.The mean SWTs monthly recording rate resulted in 0.19(Standard deviation=0.16),with 20 SWTs recorded over 5 or more different encounters(until a maximum of 30 encounters).The Jolly–Seber model(with POPAN formulation)was run in Mark software to estimate the population size.The estimated population size resulted in 171 bottlenose dolphins(95%confdence interval=137–215).Even if the detection and identifcation of signature whistles required crucial precautions,and animals could be detected differently from visual techniques,the population size estimate obtained was comparable with previous results based on physical marks data.These outcomes demonstrated that signature whistles can be considered a strongly effective tool for integrating traditional mark-recapture techniques with fnely estimated dolphins’population abundances. 展开更多
关键词 modeling methods passive acoustic monitoring signature whistles specimen identifcation mark Tursiops truncatus
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Large-scale and long-term spatiotemporal patterns of disturbances in primary beech-dominated forests in the Carpathian Mountains of Europe
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作者 Pavel Janda Arne Buechling +22 位作者 Marek Svitok Thomas A.Nagel Martin Mikolas Radek Bace Kresimir Begovic Martin Dusatko Daniela Duhova Matej Ferencik Michal Frankovic Rhiannon Gloor Ondrej Kameniar Tomas Knir Daniel Kozak Jana Agh Labusova Katarina Markuljakova Jakob Pavlin Ion Catalin Petritan Catalin-Constantin Roibu Audrey Rose Salerno Karol Ujhazy Antonin Veber Lucie Vitkova Miroslav Svoboda 《Forest Ecosystems》 2025年第5期987-997,共11页
Extreme disturbance activity is a signature of anthropogenic environmental change. Empirical information describing the historical normative limits of disturbance regimes provides baseline data that facilitates the de... Extreme disturbance activity is a signature of anthropogenic environmental change. Empirical information describing the historical normative limits of disturbance regimes provides baseline data that facilitates the detection of contemporary trends in both disturbances and community-level responses. Quantifying the attributes of historical disturbances is challenging due to their transient episodic nature, with decades-to centurieslong intervals between recurrences. Unmanaged primary forests that support centuries-old trees therefore serve as unique reference systems for quantifying past disturbance regimes. We surveyed relict stands of primary beech-dominated forests over wide environmental gradients in the Carpathian Mountains of Europe. We collected core samples from 3,026 trees in 208 field survey plots distributed across 13 forest stands in two countries. We used dendrochronological methods to analyze time-series of annually-resolved ring-width variation and to identify anomalous growth patterns diagnostic of past forest canopy removal. A 180-year record(1810–1990) of spatially and temporally explicit disturbance events(n =333) was compiled and used to derive s tatistical attributes of the disturbance regime. We quantified disturbance severity(canopy area lost), patch size, and return intervals. Our analyses describe a complex regime where a background of relatively frequent, smallscale, low-to intermediate-severity disturbance was punctuated by episodic large-scale high-severity events. Even the most severe events were non-catastrophic at a stand level, leaving significant residual tree cover that supported a continuity of ecological function. We did not detect evidence for an expected climate-induced intensification of disturbance with time, but methodological limitations precluded an assessment of disturbance activity in the decades since 1990. 展开更多
关键词 Canopy gap Climate change Disturbance regime Ecosystem resilience Natural range of variability Baseline conditions Tree mortality
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A maximum sea surface salinity tongue in the North Brazil continental shelf
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作者 Maria Cadima Paola Castellanos +2 位作者 Estrella Olmedo Joaquim Dias Edmo J.D.Campos 《Atmospheric and Oceanic Science Letters》 2025年第3期41-46,共6页
The variability of the sea surface salinity measurements provided by the Soil Moisture and Ocean Salinity mission reveals the presence of a local salinity maximum(a salty tongue)in the northwestern tropical Atlantic.T... The variability of the sea surface salinity measurements provided by the Soil Moisture and Ocean Salinity mission reveals the presence of a local salinity maximum(a salty tongue)in the northwestern tropical Atlantic.The sea surface salinity positive anomaly starts increasing in July,reaches its maximum in January,and then disappears.The local maximum of salinity appears in the late boreal autumn/winter,when the Amazon discharge is minimal and the salty water from the South Atlantic is transported by the North Brazil Current along the shelf break across the equator.The authors validate the satellite observations in this area and assess the vertical structure of the salinity maximum by using in situ measurements and an in situ-interpolated product. 展开更多
关键词 Tropical Atlantic ocean Salty tongue North Brazil current
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Practical recommendations on stretching exercise:A Delphi consensus statement of international research experts
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作者 Konstantin Warneke Ewan Thomas +17 位作者 Anthony J.Blazevich José Afonso David G.Behm Paulo H.Marchetti Gabriel S.Trajano Masatoshi Nakamura Francisco Ayala Stefano Longo Nicolas Babault Sandro R.Freitas Pablo B.Costa Andreas Konrad Antoine Nordez Arnold Nelson Astrid Zech Anthony D.Kay Olyvia Dontit Jan Wilke 《Journal of Sport and Health Science》 2025年第5期110-123,共14页
Background:Stretching has wide appeal,but there seems to exist some mismatch between its purported applications and what the evidence shows.There is compelling evidence for some stretching applications,but for others,... Background:Stretching has wide appeal,but there seems to exist some mismatch between its purported applications and what the evidence shows.There is compelling evidence for some stretching applications,but for others,the evidence seems heterogeneous or unsupportive.The discrepancies even affect some systematic reviews,possibly due to heterogeneous eligibility criteria and search strategies.This consensus paper seeks to unify the divergent findings on stretching and its implications for both athletic performance and clinical practices by delivering evidence-based recommendations.Methods:A panel of 20 experts with a blend of practical experience and scholarly knowledge was assembled.The panel meticulously reviewed existing systematic reviews,defined key terminologies(e.g.,consensus definitions for different stretching modes),and crafted guidelines using a Delphi consensus approach(minimum required agreement:80%).The analysis focused on 8 topics,including stretching's acute and chronic(long-term)effects on range of motion,strength performance,muscle hypertrophy,stiffness,injury prevention,muscle recovery,posture correction,and cardiovascular health.Results:There was consensus that chronic and acute stretching(a)improves range of motion(although alternatives exist)and(b)reduces muscle stiffness(which may not always be desirable);the panel also agreed that chronic stretching(c)may promote vascular health,but more research is warranted.In contrast,consensus was found that stretch training does not(a)contribute substantively to muscle growth,(b)serve as an allencompassing injury prevention strategy,(c)improve posture,or(d)acutely enhance post-exercise recovery.Conclusion:These recommendations provide guidance for athletes and practitioners,highlighting research gaps that should be addressed to more comprehensively understand the full scope of stretching effects. 展开更多
关键词 Range of motion Strength Movement preparation Recovery Evidence-based practice STRETCH
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双作用液压打桩锤液压系统建模及动态特性研究 被引量:1
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作者 冯小星 李泽 +3 位作者 梅卫东 季鹏 彭熙伟 张百海 《机床与液压》 北大核心 2024年第24期178-183,共6页
针对液压打桩锤打击过程中流量、压力动态变化较大及流量、压力的非线性耦合特性,建立双作用液压打桩锤液压系统的动力学模型,采用数值法求解液压打桩锤运动的动力学模型,以超大型液压打桩锤的相关数据为基础,研究液压系统参数匹配对锤... 针对液压打桩锤打击过程中流量、压力动态变化较大及流量、压力的非线性耦合特性,建立双作用液压打桩锤液压系统的动力学模型,采用数值法求解液压打桩锤运动的动力学模型,以超大型液压打桩锤的相关数据为基础,研究液压系统参数匹配对锤芯位移、速度、加速度等动态特性的影响。仿真结果表明:通过合理匹配蓄能器充气压力、液阻、液压油源流量等关键参数,可优化打桩锤的动态特性,实现打击速度快、系统稳定性好的控制效果。 展开更多
关键词 液压传动 双作用液压打桩锤 动态特性 动力学模型
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活塞式蓄能器在超大型液压打桩锤上的应用研究 被引量:1
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作者 冯小星 李泽 +3 位作者 梅卫东 季鹏 彭熙伟 唐永卫 《液压与气动》 北大核心 2024年第6期179-188,共10页
活塞式蓄能器作为液压打桩锤补偿峰值流量的辅助动力源,对液压打桩锤的动态特性有重要影响。为了优化液压打桩锤的动态特性,对双作用液压打桩锤的工作原理进行了分析,阐述了蓄能器类型的选择依据,对蓄能器容积、充气压力参数计算进行了... 活塞式蓄能器作为液压打桩锤补偿峰值流量的辅助动力源,对液压打桩锤的动态特性有重要影响。为了优化液压打桩锤的动态特性,对双作用液压打桩锤的工作原理进行了分析,阐述了蓄能器类型的选择依据,对蓄能器容积、充气压力参数计算进行了理论分析。针对液压打桩锤打击过程中流量、压力动态变化大及流量、压力非线性耦合的特性,基于AMESim软件平台建立液压打桩锤仿真模型,以4400 kJ超大型液压打桩锤的相关数据为基础,确定仿真参数,研究蓄能器充气压力分别为18、 14 MPa条件下,对锤芯位移、速度、加速度等动态特性的影响。仿真结果表明,蓄能器充气压力18 MPa,打击过程中液压缸无杆腔峰值流量不足,最大打击速度5.5 m/s,最大打击加速度14.1 m/s^(2);而蓄能器充气压力降低到14 MPa,无杆腔没有出现供油不足现象,最大打击速度6 m/s,最大打击加速度14.2 m/s^(2),实现了打击速度快、系统稳定性好的控制效果。 展开更多
关键词 液压传动 液压打桩锤 蓄能器
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Tuning photodegradation performance using carbon quantum dots and niobium pentoxide 被引量:1
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作者 Lucas Spessato Lucas H.S.Crespo +4 位作者 Marcela C.Silva Mariana S.Gibin Francielle Sato Manuel E.G.Winkler Vitor C.Almeida 《Journal of Materials Science & Technology》 CSCD 2024年第24期157-167,共11页
Carbon quantum dots(CQD)were employed as dopants to enhance the photocatalytic efficiency of Nb_(2)O_(5) by decreasing the bandgap energy and prolonging the lifetime of the photogenerated exciton by increasing conduct... Carbon quantum dots(CQD)were employed as dopants to enhance the photocatalytic efficiency of Nb_(2)O_(5) by decreasing the bandgap energy and prolonging the lifetime of the photogenerated exciton by increasing conductivity.X-ray diffraction(XRD),N_(2) porosimetry,scanning electron microscopy(SEM),electrochemical impedance spectroscopy(EIS),photoacoustic spectroscopy(PAS),X-ray photoelectron spectroscopy(XPS),Dynamic Light Scattering(DLS),zeta potential,and atomic force microscopy(AFM)were used to characterize the synthesized nanostructures.The residues from acerola processing were converted into CQD with an average size of 2.56 nm,as confirmed by AFM and the high fluorescence quantum yield of 43.32%.N_(2) physisorption results showed that the CQD were deposited on the surface of Nb_(2)O_(5),reducing the specific surface area(SBET)from 122±2.0 to 29±1.3 m^(2)g^(-1).The photocatalytic performance of CQD/Nb_(2)O_(5) was superior to that of the control materials under UV-vis light irradiation,as there was a decrease in the bandgap energy(Eg)from 2.78 to 1.93 eV.This decrease in Eg led to a significant increase in the apparent rate constant(kapp)of the MG dye from 1.90×10^(-3) s^(-1) to 42.2×10^(-3) s^(-1),demonstrating that the presence of CQD can effectively separate the photogenerated charge carriers,as it was observed from the increase in conductivity showed by Nyquist diagram. 展开更多
关键词 Acerola bagasse Malachite green Carbon dots PHOTOCATALYST Chemical kinetics
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Linking 24-h Movement Behavior Guidelines to Cognitive Difficulties,Internalizing and Externalizing Problems in Preterm Youth 被引量:1
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作者 Zhihui Cheng Ailikute Aikeremu +6 位作者 Yanping Gao Zhihao Zhang Anthony G.Delli Paoli Paolo Marcello Cunha Alyx Taylor Fabian Herold Liye Zou 《International Journal of Mental Health Promotion》 2024年第8期651-662,共12页
Background:Given the heightened risk of developmental challenges associated with preterm birth,it is crucial to explore interventions that may ameliorate potential adverse outcomes.This study aimed to examine whether ... Background:Given the heightened risk of developmental challenges associated with preterm birth,it is crucial to explore interventions that may ameliorate potential adverse outcomes.This study aimed to examine whether meeting the 24-h movement behavior(24-HMB)guidelines,which include recommendations on physical activity(PA),screen time(ST),and sleep(SL),is related to indicators of cognitive difficulties,internalizing problems(e.g.,depression and anxiety),and externalizing problems(e.g.,difficulties in making friends and arguing)in a sample of preterm youth(children and adolescents born preterm).Methods:In this cross-sectional study,data from 3410 preterm youth(aged 6 to 17 years)were included for data analyses.Multivariable logistic regression was used to investigate associations between meeting the 24-HMB guidelines and the above-mentioned health outcomes,while controlling for sociodemographic and health-related factors.Results:The prevalence of meeting 24-HMB guidelines varied across independent and integrated components of the 24-HMB guidelines.Meeting the ST guideline alone(p<0.05)and integrated guidelines(i.e.,ST+SL and ST+SL+PA)were associated with fewer cognitive difficulties and reduced internalizing and externalizing problems(p<0.05).Specifically,meeting the SL guideline alone and integrated guidelines(i.e.,SL+ST)were associated with lower odds of depression and anxiety(p<0.01).Additionally,meeting independent,and integrated(PA and/or ST)guidelines were associated with less pronounced difficulties in making friends and arguing(p<0.05).Meeting 24-HMB guidelines in an isolated and integrated manner are linked to better cognitive performance and fewer internalizing and externalizing problems in preterm youth.Conclusion:Results suggest that advocating for the implementation of the 24-HMB guidelines may reduce cognitive challenges and behavioral issues,which is of high relevance for improving public health.Future longitudinal studies in preterm youth should investigate how modifying specific 24-HMB behaviors,especially ST,influence cognitive difficulties,internalizing and externalizing problems in this vulnerable population. 展开更多
关键词 Cognitive difficulties externalizing problems internalizing problems physical activity preterm youth
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Determinant variables on the isotopic values of particulate organic matter in a neotropical floodplain
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作者 Vinícius de ANDRADE URBANO Matheus MAXIMILIAN RATZ SCOARIZE +3 位作者 Gustavo HENRIQUE ZAIA ALVES Driele DELANIRA-SANTOS Marcela da SILVA CAETANO Evanilde BENEDITO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1173-1185,共13页
Particulate organic matter(POM)is an important energy source for aquatic consumers,understanding its origin and composition is essential for understanding the energetic dynamics of aquatic environments.The aim of this... Particulate organic matter(POM)is an important energy source for aquatic consumers,understanding its origin and composition is essential for understanding the energetic dynamics of aquatic environments.The aim of this study was to analyze the relationship between POM and phytoplankton(isotopic values and chlorophyll concentration)and abiotic variables during dry and rainy seasons.Sampling was conducted in rivers and lagoons in the floodplain of the Upper ParanáRiver.We found a greater difference in ^(δ13)C values of POM between sampling points than between seasons,indicating that the composition of regional sources influences the composition of POM more than dry and rainy seasons.In addition,the concentration of chlorophyll during the dry season was positively correlated with ^(δ13)C values during that rainy period.Additionally,we found a relationship between factors limiting the growth of phytoplankton and ^(δ13)C values of POM,such as phosphate ions,indicating that variables that regulate phytoplankton growth tend to influence the composition of POM in river floodplains.Therefore,maintaining the variables that regulate the phytoplankton community is of fundamental importance for the composition of POM,an important energy source in aquatic environments. 展开更多
关键词 FRESHWATER wetland stable isotopes food web subtropical environment
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Tree structure and diversity shape the biomass of primary temperate mountain forests 被引量:2
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作者 Dheeraj Ralhan Ruffy Rodrigo +14 位作者 Heather Keith Annemiek Irene Stegehuis Jakob Pavlin Yumei Jiang Milos Rydval Juliana Nogueira Alexandre Fruleux Marek Svitok Martin Mikolas Daniel Kozak Martin Dusatko Pavel Janda Oleh Chaskovsky Catalin-Constantin Roibu Miroslav Svoboda 《Forest Ecosystems》 SCIE CSCD 2024年第4期568-579,共12页
Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of ... Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of live and dead biomass.Yet,little is known about the interactions between biomass stocks,tree genus diversity and structure across a temperate montane primary forest.Here,we investigated the relationship between tree structure(variability in basal area and tree size),genus-level diversity(abundance,tree diversity)and biomass stocks in temperate primary mountain forests across Central and Eastern Europe.We used inventory data from726 permanent sample plots from mixed beech and spruce across the Carpathian Mountains.We used nonlinear regression to analyse the spatial variability in forest biomass,structure,and genus-level diversity and how they interact with plot-level tree age,disturbances,temperature and altitude.We found that the combined effects of genus and structural indices were important for addressing the variability in biomass across different spatial scales.Local processes in disturbance regimes and uneven tree age support forest hete rogeneity and the accumulation of live and dead biomass through the natural regeneration,growth and decay of the forest ecosystem.Structural complexities in basal area index,supporte d by genus-level abundance,positively influence total biomass stocks,which was modulated by tree age and disturbances.Spruce forests showed higher tree density and basal area than mixed beech forests,though mixed beech still contributes significantly to biomass across landscapes.Forest heterogeneity was strongly influenced by complexities in forest composition(tree genus diversity,structure).We addressed the importance of primary forests as stable carbon stores,achieved through structure and diversity.Safeguarding such ecosystems is critical for ensuring the stability of the primary forest,carbon store and biodiversity into the future. 展开更多
关键词 Biodiversity indicators Biomass carbon stock Ecosystem functioning Forest composition Primary forest structure Tree size distribution
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Verification and Validation of High-Resolution Inviscid and Viscous Conical Nozzle Flows
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作者 Luciano K.Araki Rafael B.de R.Borges +1 位作者 Nicholas Dicati P.da Silva Chi-Wang Shu 《Communications on Applied Mathematics and Computation》 EI 2024年第1期533-549,共17页
Capturing elaborated flow structures and phenomena is required for well-solved numerical flows.The finite difference methods allow simple discretization of mesh and model equations.However,they need simpler meshes,e.g... Capturing elaborated flow structures and phenomena is required for well-solved numerical flows.The finite difference methods allow simple discretization of mesh and model equations.However,they need simpler meshes,e.g.,rectangular.The inverse Lax-Wendroff(ILW)procedure can handle complex geometries for rectangular meshes.High-resolution and high-order methods can capture elaborated flow structures and phenomena.They also have strong mathematical and physical backgrounds,such as positivity-preserving,jump conditions,and wave propagation concepts.We perceive an effort toward direct numerical simulation,for instance,regarding weighted essentially non-oscillatory(WENO)schemes.Thus,we propose to solve a challenging engineering application without turbulence models.We aim to verify and validate recent high-resolution and high-order methods.To check the solver accuracy,we solved vortex and Couette flows.Then,we solved inviscid and viscous nozzle flows for a conical profile.We employed the finite difference method,positivity-preserving Lax-Friedrichs splitting,high-resolution viscous terms discretization,fifth-order multi-resolution WENO,ILW,and third-order strong stability preserving Runge-Kutta.We showed the solver is high-order and captured elaborated flow structures and phenomena.One can see oblique shocks in both nozzle flows.In the viscous flow,we also captured a free-shock separation,recirculation,entrainment region,Mach disk,and the diamond-shaped pattern of nozzle flows. 展开更多
关键词 HIGH-RESOLUTION COMPRESSIBLE NAVIER-STOKES Free-shock separation Nozzle flow
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Hyperkalemia in Patients on Peritoneal Dialysis: Clinical Use Experience with New Potassium-Binders
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作者 Gennaro Argentino Mario Iorio +14 位作者 Alessandra Antonia Mele Andrea Camocardi Enrica Emanuela Cascone Maria Elena Liberti Adelia Sagliocca Andrea Pota Luigi Russo Maria Luisa Sirico Germano Terzini Michele Cavasso Chiara Mennillo Francesca Nettuno Raffaele Genualdo Giuseppe Surfaro Lucia Di Micco 《Open Journal of Nephrology》 2024年第3期324-333,共10页
Background: Patients with end-stage kidney disease (ESKD) on maintenance dialysis have a high risk of developing hyperkalemia. In addition to traditional approaches, a new option for the management of patients on dial... Background: Patients with end-stage kidney disease (ESKD) on maintenance dialysis have a high risk of developing hyperkalemia. In addition to traditional approaches, a new option for the management of patients on dialysis includes the use of a potassium binder, sodium zirconium cyclosilicate (SZC). We evaluated the effect and safety of SZC in patients with chronic PD. Objective: To present a case series that illustrates the real-world use of new potassium-binders in hyperkalemic patients on peritoneal dialysis. Methods: This case series collected 9 patients on PD with baseline potassium values > 5.5 mmol/l and who were treated with SZC 5 g once a day. Data were collected at baseline and at 1, 2, and 3 months after initiation of treatment. Results: The median age of patients was 64.5 years and the median duration of observation was 90 ± 5 days. It was observed that median serum potassium decreased (5.8 mmol/l at baseline with a range of 5.8 mmol/L - 6.8 mmol/L versus 4.5 in the third month with a range of 3.6 mmol/L - 5.3 mmol/L) after SZC treatment. Adverse events were observed in 2 (22.2%). The unique adverse event was constipation and presented in 2 patients (22.2%). Constipation was mild and transient during the observation period. No adverse events of special interest were reported. Conclusion: Normokalemia was established and maintained in this series of patients treated with SZC. No episodes of hyper- or hypo-kalemia were observed. SCZ had a good safety profile and was well tolerated over 3 months. 展开更多
关键词 SZC Sodium Zirconium Cyclosilicate HYPERKALAEMIA Peritoneal Dialysis
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In‑depth proteome characterization of endometrium and extraembryonic membranes during implantation in pig
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作者 Maria A.Gil Josep M.Cambra +3 位作者 Heriberto Rodriguez‑Martinez Cristina Cuello Inmaculada Parrilla Emilio A.Martinez 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1027-1055,共29页
Background Proteome characterization of the porcine endometrium and extraembryonic membranes is important to understand mother-embryo cross-communication.In this study,the proteome of the endometrium and cho-rioallant... Background Proteome characterization of the porcine endometrium and extraembryonic membranes is important to understand mother-embryo cross-communication.In this study,the proteome of the endometrium and cho-rioallantoic membrane was characterized in pregnant sows(PS)during early gestation(d 18 and 24 of gestation)and in the endometrium of non-pregnant sows(NPS)during the same days using LC-MS/MS analysis.The UniProtKB database and ClueGO were used to obtain functional Gene Ontology annotations and biological and functional networks,respectively.Results Our analysis yielded 3,254 and 3,457 proteins identified in the endometrium of PS and NPS,respectively;of these,1,753 being common while 1,501 and 1,704 were exclusive to PS and NPS,respectively.In addition,we iden-tified 3,968 proteins in the extraembryonic membranes of PS.Further analyses of function revealed some proteins had relevance for the immune system process and biological adhesion in endometrium while the embryonic chorion displayed abundance of proteins related to cell adhesion and cytoskeletal organization,suggesting they dominated the moment of endometrial remodeling,implantation and adhesion of the lining epithelia.Data are available via Pro-teomeXchange with identifier PXD042565.Conclusion This is the first in-depth proteomic characterization of the endometrium and extraembryonic mem-branes during weeks 3 to 4 of gestation;data that contribute to the molecular understanding of the dynamic environ-ment during this critical period,associated with the majority of pregnancy losses. 展开更多
关键词 ENDOMETRIUM Extraembryonic membranes IMPLANTATION PIG PROTEOME
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Winter is coming for ski resorts:Insights from the Apennines(Italy)
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作者 Giuliano BONANOMI Mara GHERARDELLI +1 位作者 Sabrina SPIGNO Mohamed IDBELLA 《Journal of Mountain Science》 SCIE CSCD 2024年第11期3847-3858,共12页
Ski resort abandonment is more frequent due to global warming,which progressively reduces snowpack and persistence.However,projects aiming for new resorts in the Apennines have proliferated.Such economic investments a... Ski resort abandonment is more frequent due to global warming,which progressively reduces snowpack and persistence.However,projects aiming for new resorts in the Apennines have proliferated.Such economic investments are risky,especially without long-term data on snow cover duration.Our aim,thus,is to provide the first census of abandoned ski resorts in the Apennines and compare them with the resorts currently open to understand the causes that led to their abandonment.Subsequently,we explore factors behind resort failure by analyzing the relationships between climatic,geomorphological,and economic variables.Overall,we found 101 ski resorts in the Apennines,of which 28 were open,41 closed and abandoned and 32 partially closed(i.e.,closed in more than at least 7 years in the last 10 years).The closed and partially closed resorts represent 358 km of ski slopes(44%of total available).The number of structures per resort(i.e.ski lifts,chair lifts)is higher for open compared to partially closed and closed ones.Notably,the maximum elevation reached by the resorts is higher for those open(1793 m a.s.l.)than for those partially closed(1687 m a.s.l.)and especially those closed(1577 m a.s.l.).Finally,the mean size of the resorts in terms of skiable track length is larger for open(15.7 km)than partially closed(7.1 km)and closed resorts(3.2 km).The average duration of operation for abandoned resorts is 29.5 years,varying from a maximum of 56 years to a minimum of 0 years for two sites that were never opened after reconstruction.The year of abandonment is positively associated with the maximum elevation,size,and duration of operation.Furthermore,the duration of operation is negatively correlated with the construction year.Our multivariate analysis confirms and strengthens the hypothesis for the causes that lead to abandonment are multi-factorial.Most of the closed resorts are located at low altitude and have small ski areas although some higher altitude sites have also been abandoned in recent years.This information can be useful for investors,policymakers,and stakeholders who should use it as a starting point when designing and planning new resorts to avoid future failures and the loss of public money. 展开更多
关键词 Climate change Mountain economy Snowpack duration Winter tourism Ski resort
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Spatial Variability of Microclimate Characteristics in Transition Zone of the Forest: A Case Study of Slătioara Secular Forest
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作者 Marius Dan Șandru 《Open Journal of Forestry》 2024年第4期369-396,共28页
Although the importance of forest margins in ecology is recognized, no study has been carried out in the Slătioara Secular Forest Reserve with reference to the variability of abiotic parameters along forest margins. W... Although the importance of forest margins in ecology is recognized, no study has been carried out in the Slătioara Secular Forest Reserve with reference to the variability of abiotic parameters along forest margins. With this study, we investigate to what extent microclimatic variables (air temperature—T_air, air humidity—H_air, soil temperature—T_soil, soil humidity—H_soil wind intensity (WIND) and photosynthetically active radiation intensity (PAR)) are correlated with the distance from the edge to the forest interior and the habitat type (forest interior, inner and outer edge and meadow) in the Slătioara Secular Forest Reserve. In order to measure these microenvironment variables we used the strip transect method, positioned perpendicular to the forest edge. Differences in the microenvironment variables considered in the analysis between the four habitat types were assessed using one-way ANOVA followed by Tukey-test post-hoc. To assess differences along transects, each of the six measurements went through a one-way ANOVA against distance to edge, followed by a Levene’s test for variances and finally a Tukey-test post-hoc. The results indicate that the values of microclimatic variables were significantly different in relation to the gradient of distance from the edge and to the habitat type (interior-exterior forest) and that edge habitats are significantly more susceptible to lower humidity, high winds, lower light and higher air temperatures than forest interior habitats. The ecological study of the edge areas in this reserve provides the basis for future research on forest dynamics and can guide conservation efforts to maintain the diversity and endemism of species in the Slătioara Secular Forest. 展开更多
关键词 Component Forest Microclimate Edge Effects Edge-Interior Relationships Forest Buffer Zone Edge Influence Microclimatic Influences
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Virtual Water Flows of Brazil’s International Trade
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作者 Umberto Antonio Sesso Filho Ricardo Luís Lopes +2 位作者 Carlos Alberto Gonçalves Junior Emerson Guzzi Zuan Esteves Patrícia Pompermayer Sesso 《Journal of Geoscience and Environment Protection》 2024年第10期21-37,共17页
The study aims to measure virtual water flows in Brazil’s international trade. The methodology is based on the input-output matrix, and the database used was the Eora Global Supply Chain Database. The results showed ... The study aims to measure virtual water flows in Brazil’s international trade. The methodology is based on the input-output matrix, and the database used was the Eora Global Supply Chain Database. The results showed that Brazil exported 230.8 billion m3 of virtual water per year, representing approximately 34.7% of the water footprint of the national production system in 2015. Virtual water imports totaled 111.6 billion m3 with a positive balance (net exports) of 119.2 billion m3. The country is a net exporter of this resource except for trade relations with South America and Africa, regions with negative balances of −36 billion m3 and 3 billion m3, respectively. The main destinations for virtual water exports from Brazil are Europe, with 41% of the total exported, followed by Asia and North America, with values close to 20%. The fact that Brazil is a net exporter of water makes sustainable use of the resource important, as the diversity of climate, soil, and water availability at a regional level is a challenge, which makes it essential to increase the efficiency of the use and management of water resources. 展开更多
关键词 Natural Resources Water Balance INPUT-OUTPUT ENVIRONMENT
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On the Range of Action of Adult Culex pipiens s.l.
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作者 Maria da Conceição Proença Maria Teresa Rebelo 《Journal of Biosciences and Medicines》 2024年第3期113-121,共9页
Mosquitoes are an interesting topic due to their medical importance, as they play an active role in the transmission of many pathogens and parasites, acting as vectors for various pathologies that are deadly to humans... Mosquitoes are an interesting topic due to their medical importance, as they play an active role in the transmission of many pathogens and parasites, acting as vectors for various pathologies that are deadly to humans, such as dengue, yellow fever, chikungunya, West Nile virus, encephalitis and malaria, among many others that are less common. In terms of morbidity and mortality caused by vector-borne diseases, mosquitoes are the most dangerous animals for humanity and, although they also play a role in the ecosystem as a food source for other organisms, their importance for public health cannot be overlooked. As highly efficient vectors, they put more than three billion people at risk, mainly in tropical and subtropical regions as well as in Europe, since heat waves and flooding are becoming more frequent and severe, and summers are getting longer and warmer, accelerating mosquito development, biting rates, and the incubation of the pathogens within their bodies. Female mosquitoes bite to acquire proteins for the development of their ovaries and eggs and, in the process, acquire pathogens and/or parasites from one vertebrate host and transmit them to another, usually after a short period of replication. Three of their four life stages are lived in still freshwater, so it is crucial to understand their range of action when they reach adulthood and leave the water, in order to plan and implement local prevention measures. A set of georeferenced abundance data collected in mainland Portugal over seven years was linked to cartographed water bodies in a geographic information system to estimate the distances at which Culex pipiens s.l. had a significant presence, with criteria based on the size of the catches. The result allows for an estimate of the fly range of those mosquitoes, which can be used to focus countermeasures. 展开更多
关键词 Mosquito Fly Distance Vector-Borne Diseases Culex pipiens s.l. Geographic Information Systems
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