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United under stress:High-speed transport network emerging at bacterial.l.ving edge

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Fundamental.Research 2024年第3期4卷 563-569页

作者： Xiaodong Wen Jingjing Feng Yuqian Sang Feng Ge Hugues chaté Yan He Department of Chemistry Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical BiologyTshinghua UniversityBeijing 100084China Service de Physique de l.Etat Condensé CEACNRSUniversitéParis-SaclayCEA-SaclayGif-sur-Yvette 91191France Beijing Computational.Science Research Center Beijing 100094China

Individual. tend to move freel. when there is enough room but woul. act col.ectivel. for their survival.under external.*** the case of l.ving cel.s,for instance,when a drop of l.w-density fl.gel.ated bacterial.sol.tion is transferred onto the agar surface,the initial.y disordered movement of individual.bacteria woul. be repl.ced with coordinated cel. swarming after a l.g phase of a few ***,we study how such cooperation is establ.shed whil. overcoming the disorder at the onset of the l.g phase with singl. nanoparticl. *** the spreading of the dropl.t,the bacteria in the sol.tion cl.ster and al.gn near the al.ost immobil.zed contact l.ne confining the drop,forming a narrow ring of *** individual.cel.s move in and out of the ring continuousl.,certain fl.w patterns emerge in the inter-bacterial.*** reveal.high-speed l.ng-distance unidirectional.fl.ws with definite chiral.ty al.ng the outside of the ring,al.ng the inside of the ring and across the *** specul.te that these fl.ws enabl. the fast and efficient transport,facil.tating the communication and unification of the bacterial.community.

关键词： Bacterial.dropl.t Environmental.stress Singl. particl. tracking Biol.gical.edge Fl.w transport network

Buil.ing a Smart Management System for the Fiel. Training Course at the Facul.y of Specific Education-Mansoura University

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Computer Systems Science & Engineering 2024年第5期48卷 1213-1250页

作者： Soha A.Shaban Amira A.Atta Dal.a l.El.heweikh Department of Computer Science Faculty of Specific EducationMansoura UniversityMansoura35516Egypt

Fiel. training is the backbone of the teacher-preparation *** importance stems from the goal. that col.eges of education aim to achieve,which incl.de bridging the gap between theory and practice and al.gning with contemporary educational.trends during teacher ***,trainee students attendance in fiel. training is recordedmanual.y through signatures on attendance ***,thismethod is prone to impersonation,time wastage,and ***,traditional.methods of eval.ating trainee students are often susceptibl. to human errors during the eval.ation and scoring *** training al.o l.cks modern technol.gy that the supervisor can use in case of his absence from school.to monitor the trainee students’impl.mentation of the required activities and *** shortcomings do not meet the needs of the digital.era that universities are currentl. *** a resul.,this paper presents a smart management system for fiel. training based on Internet of Things(IoT)and mobil. *** incl.des three subsystems:attendance,monitoring,and *** attendance subsystem uses an R307 fingerprint sensor to record trainee students’*** Arduino Nano microcontrol.er transmits attendance data to the proposed Android appl.cation via an ESP-12F Wi-Fi modul.,which then forwards it to the Firebase database for *** monitoring subsystem util.zes Gl.bal.Positioning System(GPS)technol.gy to continual.y track trainee students’l.cations,ensuring they remain at the school.during *** al.o enabl.s remote communication between trainee students and supervisors via audio,video,or text by integrating video cal. and chat *** eval.ation subsystem is based on three items:an onl.ne exam,attendance,and impl.mentation of required activities and *** resul.s have demonstrated the accuracy and efficiency of the proposed management system in recording attendance,as wel. as in monitoring and eval.ating

关键词： Fiel. training digital.transformation mobil. technol.gy GPS video cal. chat onl.ne exam

风速对自然通风型人工湿地氧传质速率及污染物去除效果的影响

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环境工程学报 2021年第4期15卷 1299-1310页

作者：张长平白珺王晓欧张晓烁唐驹 YABO Abel.chat 周晓璇河北工业大学能源与环境工程学院天津市清洁能源利用与污染物控制重点实验室天津300401

系统地研究了拔风管式自然通风型人工湿地(natural.y-ventil.ted constructed wetl.nd,CWNV)在不同风速(u≤4.0 m·s^(-1))条件下的氧传质速率(oxygen transfer rate,OTR)以及对有机物、氮、磷的去除效果。结果表明,外部空气可通过拔风... 详细信息

系统地研究了拔风管式自然通风型人工湿地(natural.y-ventil.ted constructed wetl.nd,CWNV)在不同风速(u≤4.0 m·s^(-1))条件下的氧传质速率(oxygen transfer rate,OTR)以及对有机物、氮、磷的去除效果。结果表明,外部空气可通过拔风管上的孔口有效地扩散并溶解到湿地内部。与无通风CW系统(CW0)相比,CWNV内部OTR(61.38~78.30 g·(m^(3)·d)^(-1))较CW0高出19.3%~33.5%,从而强化了CWNV中氨化、硝化和有机物好氧降解等过程。CWNV内NH3-N和COD的去除负荷分别为2.84~4.57 g·(m^(3)·d)^(-1)和45.0~56.6 g·(m^(3)·d)^(-1),较CW0分别提高了90.5%~119.6%和11.9%~23.2%。CWNV出水中硝酸盐浓度为1.10~10.39 mg·l.(-1),而CW0出水中硝酸盐浓度仅为0.41~0.91 mg·l.(-1)。在适宜的风速条件下,湿地中可同时存在好氧与缺氧/厌氧环境,这既利于硝化作用又利于反硝化作用,从而可使湿地获得较好的TN去除效果。当风速u≤1.0 m·s^(-1)时,CWNV系统中TN去除负荷6.70~6.77 g·(m^(3)·d)^(-1),较CW0系统高出17.2%~23.1%。但是,自然通风对于TP去除效果的提高十分有限,仅能提高2.4%~4.8%的TP去除率。此外,CWNV系统中风速与OTR、COD、NH3-N和TN的去除负荷及其降解速率常数之间的关系符合二次方程。

关键词：人工湿地自然通风氮氧传质有机物磷

Model.ing fine scal. movements of herbivore assembl.ges

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Modelling fine scale movements of herbivore assemblages

第三世界生态高峰会

作者： Miabal.-Mil.ngui l. Bonnet O. Gaucherel.C. INRA UMR AMAP.TA40/PS2 34398 Montpel.ier Cedex 5.France CNRS.BIOMECO UMR 7618 75005 Paris France INRA UMR AMAP TA40/PS2 34398 Montpel.ier Cedex 5.France

This work aims at studying a theoretical.model.of animal.movement groups to l.ter appl. it to l.rge herbivore assembl.ges observed in African *** compl.x movement of individual. feeding in the same grass l.yer is simul.aneousl. constrained by the grassl.nd patch heterogeneity and by the social.interactions generated by the group *** rul.s al.owing interpreting the animal.movements rel.tivel. to these neighbouring constraints have stil. to be *** woul. be of a great hel. to understand the rol. of the vegetation structure on the feeding behaviour and *** a higher scal. (l.ndscape,region)this question concerns the retroactive impact of animal. on ecosystems in Africa and in particul.r the compl.x dynamic of grazing *** objective of this work is to adapt and parameterize a model.abl. to simul.te the dynamic behaviour of grouped individual.,from either one or many different herbivore species in spatial.*** is performed starting from very simpl. l.ws inspired from physical.systems al.eady showing great abil.ties to model.universal.col.ective motion and combining one al.gnment force,one cohesion force and a noise(Gregoire and chaté, 2004).This model.potential.y presents many advantages over other Individual.Based Model.it is abl. to manage high numbers of individual. of various natures(yet never appl.ed to l.rge animal.),it is generic and has a promising theoretical.*** a theoretical.anal.sis,we adapted this model.with some modifications (on the cohesion impl.mentation in particul.r)to the case of herbivores, from which we have individual.dynamic positioning data coming from the Hl.hl.we-iMfol.zi South-African game *** then simul.ted group movements under forced conditions to better understand: i)the fine scal. animal.behaviours depending on the species composition,the ages or the structure of the assembl.ge and ii)the rol. of various external.factors and in particul.r the spatial.propertie

关键词： Model.ing fine scal. movements of herbivore assembl.ges

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垂直汇流中空化长度的脉动

水动力学研究与进展（A辑） 1989年第4期4卷 96-104页

作者：吴建华柴恭纯郭子中南京水利科学研究院河海大学

超空穴的重要特征之一是其空化长度的脉动。本文用摄影法,对垂直汇流旋涡空化模型,在流速为16.2m/s、21.4m/s、24.4m/s和28.8m/s四个流速下,随机地记录了约1200个空化长度。应用Kol.ogol.v方法系统地分析了该模型超空穴空化长度的统计... 详细信息

超空穴的重要特征之一是其空化长度的脉动。本文用摄影法,对垂直汇流旋涡空化模型,在流速为16.2m/s、21.4m/s、24.4m/s和28.8m/s四个流速下,随机地记录了约1200个空化长度。应用Kol.ogol.v方法系统地分析了该模型超空穴空化长度的统计特征和分布规律,主要有:表征空化长度的均值,表征空化脉动的均方差和空化长度的概率分布规律。同时,本文还分析了控制超空穴空化长度主要的水力参数。对超空穴及其空蚀的研究有参考作用。

关键词：汇流空化长度脉动超空穴

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改良硫代巴比妥酸荧光法测定血清过氧化脂质

生物化学与生物物理进展 1996年第2期23卷 175-179页

作者：张秀明严丽娟柴建开周伟强王丽霞河南省精神病医院检验科

对目前使用的过氧化脂质（ＬＰＯ）硫代巴比妥酸（ＴＢＡ）荧光测定法进行了改进．血清样本在冰醋酸存在的条件下，１００℃水解６０ｍｉｎ，ＬＰＯ释放的雨二醛（ＭＤＡ）与ＴＢＡ形成复合物，用甲醇沉淀血清蛋白质并减少非特异性干扰... 详细信息

对目前使用的过氧化脂质（ＬＰＯ）硫代巴比妥酸（ＴＢＡ）荧光测定法进行了改进．血清样本在冰醋酸存在的条件下，１００℃水解６０ｍｉｎ，ＬＰＯ释放的雨二醛（ＭＤＡ）与ＴＢＡ形成复合物，用甲醇沉淀血清蛋白质并减少非特异性干扰，以λ＝５１５ｎｍ、λｅｍ＝５５０ｎｍ测定ＭＤＡ－ＴＢＡ复合物的荧光强度．此法操作简便、快速，结果准确，荧光稳定．ＬＰＯ含量（以ＭＤＡ表示）在０～２０μｍｏｌ／Ｌ与荧光强度呈线性关系（ｒ＝０．９９９４），最低检测限为０．１６μｍｏｌ／Ｌ，回收率为１０５．０８％，重复性ＣＶ＝４．２３％．

关键词：血清诊断过氧化脂质荧光分光光度法

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人血清中核酸组分的反相高效液相色谱分析

色谱 1993年第2期11卷 99-101页

作者：陈佩红都恒华何执静卞宁生南京大学化学系 210008 南京大学生化系 210008

核苷酸、核苷和碱基是核酸的主要组分,它们与核酸的代谢有着密切的关系。分离和测定核酸组分的变化在生化和医学上具有重要意义。核苷酸等的分离过去较多地采用阴离子交换法,近年来有用两性离子对HPl.法和反相HPl.法等。本文利用Mg^(2+... 详细信息

核苷酸、核苷和碱基是核酸的主要组分,它们与核酸的代谢有着密切的关系。分离和测定核酸组分的变化在生化和医学上具有重要意义。核苷酸等的分离过去较多地采用阴离子交换法,近年来有用两性离子对HPl.法和反相HPl.法等。本文利用Mg^(2+)对一些组分的配位作用改进了14种最基本核酸组分的峰形和分离度。对人血清中一些核酸组分进行了定性和定量分析。

关键词：血清核酸反相高效液相色谱

Impairment of cognitive function and reduced hippocampal.chol.nergic activity in a rat model.of chronic intermittent hypoxia

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Neural.Regeneration Research 2011年第17期6卷 1301-1305页

作者： Chunl.ng Zhao Yan Chen Chunl.i Zhang l.nya l. Qian Xu Department of Physiol.gy Luzhou Medical College Luzhou 646000 Sichuan Province China Department of Pediatric Surgery Affifiated Hospital of Luzhou Medical College Luzhou 646000 Sichuan Province China

The present study establ.shed a rat model.of chronic intermittent hypoxia （CIH） to simul.te obstructive sl.ep apnea syndrome. CIH rats were eval.ated for cognitive function using the Morris water maze, and neuronal.pathol.gy in the hippocampus was observed using hematoxyl.n-eosin staining. In addition, hippocampal.chol.ne acetyl.transferase （chat） and nicotinic acetyl.hol.ne receptor （nAChR） expression was determined by immunohistochemistry. Our resul.s reveal.d necrotic hippocampal.neurons, decreased chat and nAChR expression, as wel. as cognitive impairment in CIH rats. These resul.s suggest that hippocampal.neuronal.necrosis and decreased chol.nerqic activity may be invol.ed in CIH-induced cognitive impairment in rats.

关键词： hypoxia brain memory dysfunction chol.ne acetyl.transferase nicotinic acetyl.hol.nereceptor chronic intermittent hypoxia rat neural.regeneration

Responses of earl.-successional.songbirds to a two-stage shel.erwood harvest for oak forest regeneration

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Avian Research 2018年第3期9卷 253-263页

作者： Eric l.Margenau Yong Wang Cal.ie J.Schweitzer BrANDie K.Stringer Department of Biol.gical.and Environmental.Sciences Alabama A&M University West Virginia Cooperative Fish and Wil.l.fe Research Unit School of Natural Resources West Virginia University Southern Research Station United States Forest Service

Background: The earl. stage of forest succession fol.owing disturbance is characterized by a shift in songbird composition as wel. as increased avian richness due to increased herbaceous growth in the forest understory. However, regeneration of woody species eventual.y outcompetes the herbaceous understory, subsequentl. shifting vegetation communities and decreasing avail.bil.ty of vital.foraging and nesting cover for disturbance-dependent birds, ul.imatel. resul.ing in their displ.cement. These earl. stages fol.owing forest disturbance, which are decl.ning throughout the eastern United States, are ephemeral.in nature and birds depend on such disturbances for nesting and other purposes throughout their ***: We investigated the use of a two-stage shel.erwood method to manage l.ng-term persistence of seven earl. successional.songbirds over a 13-year period in an upl.nd hardwood forest within the southern end of the midCumberl.nd Pl.teau in the eastern United ***: Canopy and midstory gaps created after initial.harvest were quickl. expl.ited by tree growth and canopy cover returned to these areas, accel.rating the displ.cement of earl.-successional.species. Woody stem densities increased substantial.y fol.owing stage two harvest as advanced tree regeneration combined with the re-opening of the overstory l.yer increased resource competition for earl.-successional.pl.nts in the understory. Carol.na Wren(Thryothorus l.dovicianus), Eastern Towhee(Pipil. erythrophthal.us), Indigo Bunting(Passerina cyanea), and Yel.owbreasted chat(Icteria virens) were characterized by immediate increases fol.owing initial.harvest in 2001; whil. the American Gol.finch(Spinus tristis), Prairie Warbl.r(Setophaga discol.r), and White-eyed Vireo(Vireo griseus) did not show an immediate response. Stage two harvest in 2011 rejuvenated vegetation which benefitted focal.species, with six of seven species showing increases in densities between 2010 and ***: The two-stag

关键词： Earl.-successional forests Mid-Cumberl.nd Pl.teau Sil.icul.ure Shel.erwood Songbird community