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Immediate regularization of measure-type population densities in a two-dimensional chemotaxis systemwith signal consumption

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Science China Mathematics 2021年第4期64卷 725-746页

作者： Yulan Wang micha.l winkler Zhaoyin Xiang School of Science Xihua UniversityChengdu 610039China Institut für Mathematik Universität PaderbornPaderbom 33098Germany School of Mathematical Sciences University of Electronic Science and Technology of ChinaChengdu 611731China

This paper deals with the Neumann initial-boundary value problem for a classical chemotaxis system with signal consumption in a *** contrast to previous studies which have established a comprehensive theory of global classical solutions for suitably regular nonnegative initial data,the focus in the present work is on the question to which extent initially prescribed singularities can be regularized despite the presence of the nonlinear cross-diffusive *** main result in this paper asserts that at least in the framework of radial solutions immediate regularization occurs under an essentially optimal condition on the initial distribution of the population *** precisely,it will turn out that for any radially symmetric initial data belonging to the space of regular signed Borel measures for the population density and to l^(2) for the signal density,there exists a classical solution to the Neumann initial-boundary value problem,which is smooth and approaches the given initial data in an appropriate trace sense.

关键词： chemotaxis measure valued initial data instantaneous smoothing global existence

A Smallness Condition Ensuring Boundedness in a Two-dimensional Chemotaxis-Navier-Stokes System involving Dirichlet Boundary Conditions for the Signal

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Acta Mathematica Sinica,English Series 2022年第6期38卷 985-1001页

作者： Yu lan WANG micha.l winkler Zhao Yin XIANG School of Science Xihua UniversityChengdu 610039P.R.China Institut fur Mathematik Universitat Paderborn33098 PaderbornGermany School of Mathematical Sciences University of Electronic Science and Technology of ChinaChengdu 611731P.R.China

The chemotaxis-Navier-Stokes system{nt+u・∇n=Δn−∇・(n∇c),ct+u・∇c=Δc−nc,ut+(u・∇)u=Δu+∇P+n∇φ,∇・u=0is considered in a smoothly bounded planar domainΩunder the boundary conditions(∇n−n∇c)・ν=0,c=c,u=0,x∈∂Ω,t>0,with a given nonnegative constant c_(*).It is shown that if(n_(0),c_(0),u_(0))is sufficiently regular and such that the product||n_(0)||l^(1)(Ω)||c_(0)||^(2)l^(∞)(Ω)is suitably small,an associated initial value problem possesses a bounded classical solution with(n,c,u)|_(t=0)=(n_(0),c_(0),u_(0)).

关键词： Chemotaxis Navier-Stokes system Dirichlet boundary condition

Considerations when using the activPAl monitor in field-based research with adult populations

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Journal of Sport and Health Science 2017年第2期6卷 162-178页

作者： Charlotte l.Edwardson Elisabeth A.H.winkler Danielle H.Bodicoat Tom Yates Melanie J.Davies David W.Dunstan Genevieve N.Healy diabetes research centre leicester general hospitaluniversity of leicesterLeicester LE5 4PWUK nihr leicester-loughborough diet lifestyleand physical activity biomedical research unitLeicester LE5 4PWUK school of population health the university of queenslandBrisbaneQLD 4006Australia baker idi heart and diabetes institute MelbourneVIC 3004Australia school of exercise and nutrition sciences deakin universityBurwoodVIC 3125Australia department of epidemiology and preventive medicine monash universityMelbourneVIC 3800Australia school of sport science exercise and healththe university of western australiaPerthWA 6009Australia central clinical school monash universityMelbourneVIC 3800Australia school of physiotherapy and exercise science curtin universityPerthWA 6102Australia

Research indicates that high levels of sedentary behavior(sitting or lying with low energy expenditure) are adversely associated with health. A key factor in improving our understanding of the impact of sedentary behavior(and patterns of sedentary time accumulation) on health is the use of objective measurement tools that collect date and time-stamped activity information. One such tool is the activP Al monitor. This thigh-worn device uses accelerometer-derived information about thigh position to determine the start and end of each period spent sitting/lying, standing, and stepping, as well as stepping speed, step counts, and postural transitions. The activP Al is increasingly being used within field-based research for its ability to measure sitting/lying via posture. We summarise key issues to consider when using the activP Al in physical activity and sedentary behavior field-based research with adult populations. It is intended that the findings and discussion points be informative for researchers who are currently using activP Al monitors or are intending to use them. Pre-data collection decisions, monitor preparation and distribution, data collection considerations, and manual and automated data processing possibilities are presented using examples from current literature and experiences from 2 research groups from the UK and Australia.

关键词： populations monitor lying collection accelerometer expenditure Australia stepping currently intended

Association between Taenia solium infection and HIV/AIDS in northern Tanzania: a matched cross sectional-study

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Infectious Diseases of Poverty 2016年第1期5卷 1022-1036页

作者： Veronika Schmidt Christian Kositz Karl-Heinz Herbinger Hélène Carabin Bernard Ngowi Ezra Naman Patricia P.Wilkins John Noh William Matuja Andrea Sylvia winkler Department of Neurology University HospitalKlinikum rechts der IsarTechnical University Munich(TUM)Ismaninger Str.2281675 MunichGermany Department of Infectious Diseases and Tropical Medicine(DITM) Medical Center of the University of MunichMunichGermany Department of Biostatistics and Epidemiology University of Oklahoma Health Sciences CenterOklahoma CityUSA Muhimbili Medical Research Centre National Institute for Medical Research(NIMR)Dar es SalaamTanzania HIV Care and Treatment Centre Haydom Lutheran HospitalHaydomTanzania Division of Parasitic Diseases and Malaria Center for Global HealthCenters for Disease Control and Prevention(CDC)AtlantaUSA Department of Neurology Muhimbili University of Health and Allied SciencesDar es SalaamTanzania Centre of Global Health University of OsloOsloNorway

Background:The frequency of Taenia solium,a zoonotic helminth,is increasing in many countries of sub-Saharan Africa,where the prevalence of the human immunodeficiency virus(HIV)is also ***,little is known about how these two infections *** aim of this study was to compare the proportion of HIV positive(+)and negative(−)individuals who are infected with Taenia solium(TSOl)and who present with clinical and neurological manifestations of cysticercosis(CC).Methods:In northern Tanzania,170 HIV+individuals and 170 HIV–controls matched for gender,age and village of origin were *** staging and serological tests for TSOl antibodies(Ab)and antigen(Ag)were ***(NCC)was determined by computed tomography(CT)using standard diagnostic *** manifestations were confirmed by a standard neurological *** addition,demographic,clinical and neuroimaging data were ***,CD4^(+)cell counts as well as information on highly active antiretroviral treatment(HAART)were ***:No significant differences between HIV+and HIV–individuals regarding the sero-prevalence of taeniosis-Ab(0.6%vs 1.2%),CC-Ab(2.4%vs 2.4%)and CC-Ag(0.6%vs 0.0%)were detected.A total of six NCC cases(3 HIV+and 3 HIV–)were detected in the group of matched *** individuals(1 HIV+and 1 HIV–)presented with headaches as the main symptom for NCC,and four with asymptomatic *** the HIV+group,TSOl was not associated with CD4+cell counts,HAART duration or HIV ***:This study found lower prevalence of taeniosis,CC and NCC than had been reported in the region to *** low level of infection may have resulted in an inability to find cross-sectional associations between HIV status and TSOl infection or *** sample sizes will be required in future studies conducted in that area to conclude if HIV influences the way NCC manifests itself.

关键词： Taenia solium Taeniosis Cysticercosis Neurocysticercosis HIV AIDS Co-infection Helminth Tapeworm Prevalence

Prey quality impact on the feeding behavior and lipid composition of winter flounder(Pseudopleuronectes americanus)larvae

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Aquaculture and Fisheries 2018年第4期3卷 145-155页

作者： Maria Angelica Martinez-Silva Celine Audet Gesche winkler Rejean Tremblay Institute de sciences de la mera Rimouski Universite du Quebeca Rimouski310 Allee des UrsulinesRimouskiQC G5L 2Z9Canada

Copepods are the main natural food of many marine fish ***,enriched rotifers are the most commonly used live prey in larval *** on the feeding behavior,growth,survival,and fatty acid(FA)composition of winter flounder larvae fed with copepods and rotifers were determined and compared to the FA composition of the two live *** of Eurytemora *** Acartia sp.,two of the main species of copepods present in the *** estuary,showed no significant differences in their essential fatty acid profiles,suggesting similar nutritional ***,only Eurytemora herdmani was compared to enriched rotifers in this *** nauplii were characterized by higher levels of essential fatty acids,particularly docosahexaenoic acid(DHA)and eicosapentaenoic acid(EPA).The selective incorporation of essential fatty acids from diets in larval tissues(polar lipids)indicated that nauplii might better fulfill larval nutritional requirements for DHA than ***,larval behavior was modified according to the diet:larvae fed with nauplii spent more time swimming with no changes in the occurrence of hunting events.

关键词： Winter flounder Copepods Rotifers Nutrition Fatty acids

Reduced nitrogen availability during growth improves quality in red oak lettuce leaves by minimizing nitrate content, and increasing antioxidant capacity and leaf mineral content

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Agricultural Sciences 2011年第4期2卷 477-486页

作者： Dario Stefanelli Sonja winkler Rod Jones 不详

Overuse of N in lettuce production can lead to environmental problems caused by leaching and the accumulation of harmful nitrates in edible tissues. This study investigated the effect of applied nitrogen (N) concentrations between 40 and 2400 mg·l–1 on growth, nitrate accumulation, mineral leaf content, and antioxidant capacity in Oak leaf lettuce cv. “Shiraz” grown under hydroponic conditions in Australia. Yield (g FW) increased with nitrogen (N) application rate up to 1200 mg·l–1, as did leaf N content, while C:N declined. Nitrogen Utilization Efficiency (NUtE) increased rapidly from 40 to 75 mg·l–1 applied N, leveling at 150 mg·l–1 with no subsequent effect of N concentrations between 400 and 2400 mg·l–1. Nitrate content rose significantly with increased N, particularly at 1200 and 2400 mg·l–1. leaf total plant phenolic content (TPP) and antioxidant capacity (measured by ferric reducing antioxidant power—FRAP) were both maximal at 75 and 400 mg·l–1 applied N, while highest oxygen radical absorption capacity (ORAC) values were found in leaves supplied with low N (40 to 400 mg·l–1). Applied N as calcium nitrate also significantly affected leaf mineral content as B, Mg, Mn, and Zn significantly decreased with increasing N. These results indicate that N applications of 1200 mg·l–1 or higher can result in reduced antioxidant capacity and mineral content in lettuce leaves.

关键词： lactuca sativa l. Hydroponic Phenolic Content Zinc Manganese Magnesium

Transgenerational bone toxicity in F3 medaka (Oryzias latipes) induced by ancestral benzo[a]pyrene exposure: Cellular and transcriptomic insights

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Journal of Environmental Sciences 2023年第5期127卷 336-348页

作者： Jiezhang Mo Miles Teng Wan DorisWai-Ting Au Jingchun Shi Nathan Tam Xian Qin Napo K.M.Cheung Keng Po lai Christoph winkler Richard Yuen-Chong Kong Frauke Seemann Southern Marine Science and Engineering Guangdong laboratory(Guangzhou) Guangzhou 510000China Shenzhen Key laboratory for the Sustainable Use of Marine Biodiversity Research Centre for the Oceans and Human HealthShenzhen Research InstituteCity University of Hong KongShenzhen 518057China State Key laboratory of Marine Pollution and Department of Chemistry City University of Hong KongHong Kong SARChina laboratory of Environmental Pollution and Integrative Omics Guilin Medical UniversityHuan Cheng North 2nd Road 109Guilin 541004China Department of Biological Sciences National University of Singapore119077Singapore Center for Coastal Studies and Department of life Sciences Texas A&M University-Corpus ChristiCorpus ChristiTexas 78412USA

Benzo[a]pyrene(BaP),a ubiquitous pollutant,raises environmental health concerns due to induction of bone toxicity in the unexposed *** of F0 ancestor medaka(Oryzias latipes)to 1μg/l BaP for 21 days causes reduced vertebral bone thickness in the unexposed F3 male *** reveal the inherited modifications,osteoblast(OB)abundance and molecular signaling pathways of transgenerational BaP-induced bone thinning were *** analysis showed a reduction in OB *** of the miRNA and mRNA transcriptomes revealed the dysregulation of Wnt signaling(frzb/ola-miR-1–3p,sfrp5/ola-miR-96–5p/miR-455–5p)and bone morphogenetic protein(Bmp)signaling(bmp3/ola-miR-96–5p/miR-181b-5p/miR-199a-5p/miR-205–5p/miR-455–5p).Both pathways are major indicators of impaired bone formation,while the altered Rank signaling in osteoclasts(c-fos/miR-205–5p)suggests a potentially augmented bone ***,a typical BaP-responsive pathway,the Nrf2-mediated oxidative stress response(gst/ola-miR-181b-5p/miR-199a-5p/miR-205),was also ***,mRNA levels of epigenetic modification enzymes(e.g.,hdac6,hdac7,kdm5b)were found *** findings indicated that epigenetic factors(e.g.,miRNAs,histone modifications)may directly regulate the expression of genes associated with transgenerational BaP bone toxicity and warrants further *** identified candidate genes and miRNAs may serve as potential biomarkers for BaP-induced bone disease and as indicators of historic exposures in wild fish for conservation purposes.

关键词： Polycyclic aromatic hydrocarbons (PAHs) Transcriptome Impaired bone formation Molecular pathways MicroRNAs Medaka(Oryzias latipes)

Reduction in Nitrogen Prior to Harvest Increases Phenolic Content of Baby Red lettuce leaves

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Agricultural Sciences 2014年第6期5卷 546-554页

作者： Dario Stefanelli Sonja winkler Christine Frisina Rod Jones Department of Environment and Primary Industries Agriculture Research Division Victoria Australia

This study investigated baby red lettuce leaves grown in an inert media and fertigated with 300 or 1000 mg·l-1 CaNO3-N (19% Ca;15.5% N), and the effects of altering CaNO3-N concentrations in the last 7 days prior to harvest on yield, antioxidant capacity, TPP and vitamin C content. Plants receiving 1000 mg·l-1 CaNO3-N had a significantly higher leaf FW than those fertilized with 300 mg·l-1 CaNO3-N after both 21 and 28 days. Pulsing plants with 1000 mg·l-1 CaNO3-N for 7 days after 21 days at 300 mg·l-1 CaNO3-N resulted in a significant increase in FW of 14%, compared with plants receiving 300 mg·l-1 CaNO3-N. After 28 days plants fertilized with nitrogen at 300 mg·l-1 CaNO3-N were significantly higher in TPP than those fertilized with 1000 mg·l-1 CaNO3-N. While there was no significant effect on TPP of a 7-day 1000 mg·l-1 CaNO3-N pulse added to 300 mg·l-1 CaNO3-N, a 7-day pulse of 300 mg·l-1 CaNO3-N added to 1000 mg·l-1 CaNO3-N resulted in a significant increase in TPP. These results indicate that reducing the N availability for 7 days prior to harvest can result in a significant increase in plant phenolic content with no adverse effect on yield.

关键词： Yield Production Vitamin C Antioxidant Capacity

地震作用下桩-土-核电结构相互作用的异步分析方法

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振动工程学报 2024年第6期37卷 1033-1042页

作者：吕昊陈少林陆新宇孙晓颖南京航空航天大学航空学院结构工程与力学系江苏南京210016 南京航空航天大学民航学院土木与机场工程系江苏南京211106 中国地震局工程力学研究所黑龙江哈尔滨150080 中国核电工程有限公司北京100840

为拓展核电厂的选址范围,有必要对非基岩场地桩基情形的核电结构进行地震安全性评估。在目前的桩-土-结构相互作用分析方法中,winkler地基梁模型以及p-y法都将桩-土-结构相互作用问题进行了简化,难以反映复杂地基情形。整体有限元法可... 详细信息

为拓展核电厂的选址范围,有必要对非基岩场地桩基情形的核电结构进行地震安全性评估。在目前的桩-土-结构相互作用分析方法中,winkler地基梁模型以及p-y法都将桩-土-结构相互作用问题进行了简化,难以反映复杂地基情形。整体有限元法可考虑复杂地基情形,但计算量较大,效率较低。本文基于高效的三维时域土-结构相互作用分区分析(Partitioned Analysis of Soil-Structure Interaction,PASSI)方法,实现桩基与土体分别采用不同时间步距的计算方法,避免土体采用桩基相对较小的时间步距而增加不必要的计算量。本文以AP1000核岛结构作为研究对象,建立了桩-土-核电结构相互作用的三维有限元模型并对其进行分析。通过输入脉冲波验证了该异步算法的有效性,并结合运动相互作用和惯性相互作用,分析了桩身最大剪力和最大弯矩的特点。分析了桩-土-核电结构在地震波输入下的响应。由于桩的自由度数相对于土体的自由度数可以忽略不计,采用桩-土异步算法时,桩附加的计算量可以忽略,这种高效方法有望用于大型核电结构的桩-土-结构动力相互作用分析中。

关键词：桩-土-结构相互作用土-结构相互作用分区分析方法运动相互作用异步算法核电抗震设计