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Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 139-156页

作者： h.hoSSEINI o.BALILAShAKI Department of Mechanical Engineering Faculty of EngineeringGolestan University

The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically. It is assumed that the source is located outside the cavity at a specified distance from the borehole axis. The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed. Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid, empty borehole, and rigid inclusion with a hard boundary is employed for the analysis. Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions, the proposed boundary conditions at the interface are satisfied. Stresses are formulated by means of wave potential functions in a three-dimensional(3D) manner. The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra. Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis. To give an overall outline of the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values. In addition, the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole. Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases, and good agreement is achieved.

关键词： cylindrical cavity o353.4 point source porous medium stress concentration wave-field transformation

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统计学简史

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统计学 2000年第2期

作者： h.o.lancaster

1 起源，分布统计是初产生于研究对国家，特别是对其经济以及人口的描述。当时现代数学尚未形成。因此那时的统计史基本上是经济史的范畴。现代统计主要起源于研究总体（population），变差（variation）和简化数据（reduction of data...

1 起源，分布统计是初产生于研究对国家，特别是对其经济以及人口的描述。当时现代数学尚未形成。因此那时的统计史基本上是经济史的范畴。现代统计主要起源于研究总体（population），变差（variation）和简化数据（reduction of data）。第一个经典文献属于John Graunt （1620-1674），其具有技巧的分析指出了把一些庞杂、令人糊涂的数据化简为几个说明问题的表格的价值。他注意到在非瘟疫时期，一个大城市每年死亡数有统计规律，而且出生儿的性别比为1.08，即每生13个女孩就有14个男孩。大城市的死亡率比农村地区要高。在考虑了已知原因的死亡及不知死亡年龄的情况下，Graunt估计出了六岁之前儿童的死亡率，并相当合理地估计出了母亲的死亡率为1.5%。因此，他从杂乱无章的材料中得出了重要的结论。他还给出了一个新的生命表。Edmond halley（哈雷）（1656-1742）利用了Breslau 的记有死亡年龄的数据，改进了Graunt的生命表并引进了死亡率的定义。瑞士数学家Leonhard Euler（欧拉）（1707-1783）提出了平稳生命表的概念。 John De Witt（1625-1672）等人最早讨论退休金和人寿保险的方案。 Thomas Robert Malthus（马尔萨斯）（1766-1834）， Alfred JamesLotke（1880-1949），Ronald Aylmer Fisher（费歇）（1890-1962 ），及William Feller（费勒）（1906-1970 ）等人用渐趋复杂的数学来研究生命表的理论，这对人类及其它总体的动力学描述具有显著意义。William Petty（1623-1687）是Graunt同时代的经济学家及朋友。他认为需要建立中央统计部来利用人口统计学的知识；由行政区利用列出记录年龄，性别，婚姻状况等细节的记录表格来收集数据；要有出生，死亡，婚姻，收入，教育和商业等方面的统计数据。当时在研究诸如死亡等时间序列时，Graunt注意到了随机的起伏；但他仅以机械的术语加以描述—把这些与钟表运动的忽动忽停相联系。实际上，这种不规则的变化也影响赌博和天文学。因此，其后进一步导致了随机误差的误差分布概念的出现。赌博产生了第一个机会事件的模型：如果硬币就骰子的每一面都有相同概率，则导致估计抛一个均衡的硬币所出现的正面次数或掷一个均衡的骰子的总点数。更一般地，Abraham de Moivre（棣美佛）（1667-1754）导出了对二项分布的一个近似；这使每一个概率都等于正态曲线下的一块面积，这是一种的中心极限定理。Pierre simon Laplace（拉普拉斯）（1749-1827）导出了对男子出生比例的类似的渐近公式。 Jacob Bernoulli（伯努利）（1654-1705）以弱大数定律支持了对大样本均值的使用。Tomas simpson（辛普森）（1710-1761）计算了同分布随机变量和的精确分布，同样也支持了对大样本均值的使用。

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Piling up multidecker pyrgos[n]cages as antibacterial materials

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Science China Materials 2025年第1期68卷 314-316页

作者： Miguel A.Liuzzi-Vaamonde Jackson B.lancaster Samantha A.Mason Yuanning Feng Department of Chemistry and Biochemistry The University of OklahomaOklahoma 73019United States

The development of antibiotics is regarded as one of the most significant scientific advances in modern medicine. Before the commercialization of antibiotics, infectious diseases were catastrophic throughout history [1]. Penicillin was used to treat serious infections in the 1940s, but unfortunately, with the introduction of antibiotics came the emergence of antibiotic resistance [2,3]. Evolved and adapted methicillin-resistant Staphylococcus aureus (MRSA) strains are presently impacting community and healthcare systems across the globe [4].

关键词： diseases adapted antibiotics

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Blood biomarkers of Alzheimer’s disease:important considerations for use in clinical practice

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Neural Regeneration Research 2025年第1期20卷 205-206页

作者： Sarah Fullam Sean o’Dowd Antoinette o’Connor Department of Neurology Tallaght University HospitalDublinIreland Academic Unit of Neurology Trinity College DublinIreland

Introduction:Fluid and positron emission tomography(PET)biomarkers that enable the detection of the hallmark proteins of Alzheimer’s disease(AD)(amyloid and tau)have revolutionized our approach to the diagnosis of *** evolution of AD diagnostic criteria to include biological characterization(Alzheimer’s Association Working Group,2023)provides an appropriate framework to reduce levels of clinico-pathologic mismatch and improve in-vivo diagnostic *** the therapeutic landscape for neurodegenerative disease evolves,it is increasingly incumbent on clinicians to provide timely,and pathologically precise diagnoses for ***,the expensive and invasive nature of these tests limits their scalability.

关键词： Blood Alzheimer diagnosis

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Insights into transferal to fractal space modeling:delayed forced helmholtz-Duffing oscillator with the non-perturbative approach

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Communications in Theoretical Physics 2025年第1期77卷 11-22页

作者： Yusry o El-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The damped helmholtz-Duffing oscillator is a topic of great interest in many different fields of study due to its complex *** transitioning from conventional continuous differential equations to their fractal counterparts,one gains insights into the system's response under new mathematical *** paper presents a novel method for converting standard continuous differential equations into their fractal *** conversion occurs after the nonlinear system is transformed into its linear *** analyses show that there are several resonance sites in the fractal system,which differ from the one resonance point found in the continuous *** important finding is that the fractal system loses some of its stabilizing power when decaying behavior is transformed into a diffuse ***,a decrease in the fractal order in resonance settings shows a stabilizing impact,highlighting the dynamics'complexity inside fractal *** endeavor to convert to fractals is a revolutionary technique that is being employed for the first time.

关键词： nonlinear oscillations helmholtz-Duffing oscillator forced with delay effect non-perturbative methodology stability outlines new perspectives on transferal to fractal space modeling

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Combining slow-release fertilizer and plastic film mulching reduced the carbon footprint and enhanced maize yield on the Loess Plateau

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Journal of Environmental Sciences 2025年第1期147卷 359-369页

作者： Xiaoqing han Pengfei Dang Lechen Liao Fangqi Song Miaomiao Zhang Maoxue Zhang Guoqing Li Shuyue Wen Ning Yang Xiping Pan Xiaofan Wang WenWang Xiaoliang Qin Charles o.Joseph Kadambot h.M.Siddique College of Agronomy Key Laboratory of Crop Physi-ecology and Tillage Science in Northwestern Loess PlateauNorthwest A&F UniversityYanglingShaanxi 712100China Department of Crop Sciences and Beekeeping Technology College of Agricultural Sciences and Food Technology University of Dar es SalaamMwalimu Julius Nyerere Mlimani CampusP.O.Box 35091Dar es SalaamTanzania College of Life Science Yulin UniversityChongwen Road No.4YulinShaanxi719000China The UWA Institute of Agriculture and School of Agriculture&Environment The University of Western AustraliaPerth WA 6001Australia

Agricultural practices significantly contribute to greenhouse gas(GhG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize *** film mulching is commonly used in the Loess Plateau *** slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop *** these techniques represents a novel agricultural approach in semi-arid ***,the impact of this integration on soil carbon storage(SoCS),carbon footprint(CF),and economic benefits has received limited research ***,we conducted an eight-year study(2015-2022)in the semi-arid northwestern region to quantify the effects of four treatments[urea supplied without plastic film mulching(CK-U),slow-release fertilizer supplied without plastic film mulching(CK-S),urea supplied with plastic film mulching(PM-U),and slow-release fertilizer supplied with plastic film mulching(PM-S)]on soil fertility,economic and environmental *** results revealed that nitrogen fertilizer was the primary contributor to total GhG emissions(≥71.97%).Compared to other treatments,PM-S increased average grain yield by 12.01%-37.89%,water use efficiency by 9.19%-23.33%,nitrogen accumulation by 27.07%-66.19%,and net return by 6.21%-29.57%.Furthermore,PM-S decreased CF by 12.87%-44.31%and CF per net return by 14.25%-41.16%.After eight years,PM-S increased SoCS(0-40 cm)by 2.46%,while PM-U decreased it by 7.09%.These findings highlight the positive effects of PM-S on surface soil fertility,economic gains,and environmental benefits in spring maize production on the Loess Plateau,underscoring its potential for widespread adoption and application.

关键词： Plastic film mulching Slow-release fertilizer Maize grain yield Carbon footprint Economic benefits

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Neuroinflammation revisited through the microglial lens

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Neural Regeneration Research 2025年第7期20卷 1989-1990页

作者： Renato Socodato João B.Relvas Institute of Research and Innovation in health(i3S)and Institute for Molecular and Cell Biology(IBMC) University of PortoPortoPortugal Department of Biomedicine Faculty of Medicine of the University of Porto(FMUP)PortoPortugal

Neuroimmunology is emerging as a pivotal field,shedding light on the intricate dialogues between the central nervous system(CNS)and the immune *** exploration is particularly significant in understanding microglia,the CNS’s innate immune cells,beyond the conventional conflation of“neuroinflammation”and“microglial activation.”This conflation has clouded the true complexity of these processes,potentially stalling scientific progress and the development of new *** challenge the long-standing perspectives that have oversimplified these interactions,advocating for a deeper exploration of the dynamic relationship between neuroinflammation and microglial *** dissecting specific molecular pathways,we aim to illuminate their elaborate roles in neuroinflammatory responses,especially in the context of Alzheimer’s disease(AD).here,neuroinflammation is not merely a passive observer or a direct antagonist but a complex agent in the disease’s *** article calls for a significant paradigm shift towards an integrative,multi-omics approach to *** such a comprehensive framework is crucial for advancing our understanding of neuroinflammatory conditions and paving the way for targeted therapeutic strategies for brain diseases.

关键词： inflammation simplified activation

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Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： Christopher J.o’Connell Matthew J.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA James L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain injury(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic

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Cryopreservation of bovine sperm causes single‑strand DNA breaks that are localized in the toroidal regions of chromatin

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Journal of Animal Science and Biotechnology 2025年第1期16卷 92-106页

作者： Jordi Ribas‑Maynou Rodrigo Muiño Carolina Tamargo Marc Yeste Biotechnology of Animal and human Reproduction(TechnoSperm) Institute of Food and Agricultural TechnologyUniversity of GironaS17003 GironaSpain Unit of Cell Biology Department of BiologyFaculty of SciencesUniversity of GironaS17003 GironaSpain Present Address:Unit of Cell Biology and Medical Genetics Department of Cell BiologyPhysiology and ImmunologyAutonomous University of BarcelonaS08193 BellaterraSpain Department of Animal Pathology Faculty of Veterinary MedicineUniversity of Santiago de CompostelaS15705 LugoSpain Department of Animal Selection and Reproduction The Regional Agri-Food Research and Development Service of Asturias(SERIDA)S33394 GijónSpain Catalan Institution for Research and Advanced Studies(ICREA) S08010 BarcelonaSpain

Background Sperm cryopreservation is widely used in the cattle industry,as it allows for disassociating the localiza-tion of sires and the collection of semen from the timing of artificial *** freeze-thawing is known to impair sperm DNA integrity,whether the damage induced consists of single-(SSB)or double-strand breaks(DSB)has not been *** addition,no previous study has addressed if DNA breaks preferentially reside in specific genome regions such as those forming the toroid linker regions,or are rather spread throughout the regions linked to *** main aim of the present work,therefore,was to elucidate the type and localization of the DNA damage generated by cryopreservation and to evaluate its impact on artificial insemination outcomes in *** The incidence of SSB and DSB was evaluated in 12 ejaculates before and after cryopreservation with the Comet assay,and the localization of the DNA breaks was assessed using pulsed-field gel electrophoresis(PFGE).Before cryopreservation,the incidence of SSB was 10.99%±4.62%and involved 20.56%±3.04%of sperm cells,whereas these figures significantly(Po 34.11%±3.48%and 53.36%±11.00%in frozen-thawed *** contrast,no significant differences in the incidence of DSB were observed(P>0.990)before and after cryopreservation(before:incidence of 13.91%±1.75%of sperm DNA affecting 56.04%±12.49%of sperm cells;after:incidence of 13.55%±1.55%of sperm DNA involving 53.36%±11.00%of sperm cells).Moreover,PFGE revealed that the percentage of sperm DNA fragments whose length was shorter than a toroid(han before freeze-thawing(15.57%±4.53%).These differences indicated that the DNA breaks induced by cryopreservation affect the regions condensed in protamines,which are structured in *** the other hand,in vivo fertility rates were associated to the incidence of SSB and DSB in frozen-thawed sperm(P=0.032 and P=0.005),but not w

关键词： Cattle DNA damage Fertility Sperm Toroid linker regions

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Seasonal influence on miRNA expression dynamics of extracellular vesicles in equine follicular fluid

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Journal of Animal Science and Biotechnology 2025年第1期16卷 136-152页

作者： Jean M.Feugang Ahmed Gad Nico G.Menjivar Ghassan M.Ishak Samuel Gebremedhn Melba o.Gastal Notsile h.Dlamini Radek Prochazka Eduardo L.Gastal Dawit Tesfaye Department of Animal and Dairy Sciences Mississippi State UniversityMississippi StateMS 39762USA Animal Reproduction and Biotechnology Laboratory(ARBL) Department of Biomedical SciencesCollege of Veterinary Medicine and Biomedical SciencesColorado State UniversityFort CollinsCO 80523USA Department of Animal Production Faculty of AgricultureCairo UniversityGiza 12613Egypt Department of Surgery and obstetrics College of Veterinary MedicineUniversity of BaghdadBaghdad 10011Iraq Animal Science School of Agricultural SciencesSouthern Illinois UniversityCarbondaleIL 62901USA J.R.Simplot Company KunaID 83634USA Institute of Animal Physiology and Genetics Czech Academy of SciencesLiběchov 27721Czech Republic

Background ovarian follicular fluid(FF)is a dynamic environment that changes with the seasons,affecting follicle development,ovulation,and oocyte *** in the follicles release tiny particles called extracellular vesicles(EVs)containing vital regulatory molecules,such as microRNAs(miRNAs).These miRNAs are pivotal in facilitating commu-nication within the follicles through diverse signaling and information transfer ***-coupled miRNA signaling is implicated to be associated with ovarian function,follicle and oocyte growth and response to various environmen-tal ***,we investigated how seasonal variations directly influence the ovulatory and anovulatory states of ovarian follicles and how are they associated with follicular fluid EV-coupled miRNA dynamics in *** Ultrasonographic monitoring and follicular fluid aspiration of preovulatory follicles in horses during the ano-vulatory(spring:non-breeding)and ovulatory(spring,summer,and fall:breeding)seasons and subsequent EV isola-tion and miRNA profiling identified significant variation in EV-miRNA cargo *** identified 97 miRNAs with dif-ferential expression among the groups and specific clusters of miRNAs involved in the spring transition(miR-149,-200b,-206,-221,-328,and-615)and peak breeding period(including miR-143,-192,-451,-302b,-100,and let-7c).Bioinformatic analyses showed enrichments in various biological functions,e.g.,transcription factor activity,transcrip-tion and transcription regulation,nucleic acid binding,sequence-specific DNA binding,p53 signaling,and post-trans-lational *** analyses revealed distinct sets of significantly up-and down-regulated miRNAs associ-ated with spring anovulatory(Cluster 1)and summer ovulation–the peak breeding season(Clusters 4 and 6).Conclusions The findings from the current study shed light on the dynamics of FF-EV-coupled miRNAs in relation to equine ovulatory and anovulatory seasons,and their roles in understanding the

关键词： Extracellular vesicle Follicle growth Follicular fluid horse Mare ovulation Pre-ovulation Seasonal breeding

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