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Trophic Status of Shallow Lakes of La Pam.a (Argentina) and Its Relation with the Land Use in the Basin and Nutrient Internal Load

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Journal of Environm.ntal Protection 2013年第11期4卷 51-60页

作者： Santiago A. Echaniz alicia m. vignatti Departam.nto de Ciencias Biológicas Facultad de Ciencias Exactas y Naturales Universidad Nacional de La Pampa Santa Rosa Argentina.

Phosphorus and nitrogen are essential nutrients for living organism.. Their concentration in the water of an aquatic ecosystem.is one of the factors responsible for the trophic status of the lake and is related to the soils of the region and to the hum.n activities carried out in their basins. These nutrients are also found in the bottom.sedim.nts, where they can either be retained or re-enter the water colum.. Since the inform.tion about the concentrations of nutrients in the water of som. lakes of La Pam.a (Argentina) is fragm.ntary, the aim.of this study is to describe the trophic status of som. shallow lakes of the sem.arid center of Argentina and analyze its relation with the hum.n activities in their basins, the concentrations of nutrients and organic m.tter and particle size distribution of sedim.nts. To this end, we studied ten shallow lakes subjected to different anthropogenic influences (agriculture, agriculture and livestock and im.acted by cities). All were hypertrophic and the concentrations of total phosphorus and total nitrogen were am.ng the highest reported globally. Since som. lakes had no fish, cladoceran grazing (top-down effect) led them.have reduced concentrations of phytoplankton chlorophyll-a and high water transparency. This relativizes the use of these param.ters to determ.ne the trophic status. The sedim.nts of seven of the studied lakes were predom.nated by fine sands, whereas three were predom.nated by silts. Nutrient and organic m.tter content were high, with higher concentrations in lakes with prevalence of fine particles. The reduced adsorption capacity of sedim.nts, the resuspension by wind, the anthropogenic input and the accum.lation favored by the arheic character of the basins would explain the high concentrations of nutrients in the water of these Pam.ean environm.nts.

关键词： Eutrophication Trophic State Total Phosphorus Shallow Lakes Internal Load Land Use

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Outrunning the Red Queen： bystander activation as a m.ans of outpacing innate im.une subversion by intracellular pathogens

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Cellular & m.lecular Im.unology 2017年第1期14卷 14-21页

作者： alicia m.Holm.ren Cam.ron A m.Conkey Sunny Shin Depatm.nt of m.crobiology Perelman School of Medicine University of Pennsylvania Philadelphia PA 19104-6060 USA Im.unology Graduate Group Perelman School of Medicine University of Pennsylvania Philadelphia PA 19104-6060 USA

Originally described by the late evolutionary biologist Leigh Van Valen, the Red Queen hypothesis posits that the evolutionary arm. race between hosts and their pathogens selects for discrete, genetically encoded events that lead to com.etitive advantages over the other species. Exam.les of im.une evasion strategies are seen throughout the co-evolution of the m.m.alian im.une system.and pathogens, such as the enzym.tic inactivation of nuclear factor-KB signaling or host translation by pathogen-encoded virulence factors. Such im.unoevasive m.neuvers would be expected to select for the evolution of innate im.une counterstrategies. Recent advances in our understanding of host im.unity and m.crobial pathogenesis have provided insight into a particular innate im.une adaptation, term.d bystander activation. Bystander activation occurs as a consequence of infected cells alerting and instructing neighboring uninfected cells to produce inflam.atory m.diators, either through direct cell contact or paracrine signals. Thus, bystander activation can allow the im.une system.to overcom. the ability of pathogens to disarm.im.une signaling in directly infected cells. This review presents an overview of the general hallm.rks of bystander activation and their em.rging role in innate im.unity to intraceUular pathogens, as well as exam.les of recent m.chanistic discoveries relating to the bystander activation during infection with specific pathogens relevant to hum.n health and disease.

关键词： cell-cell com.unication cGAS exosom.s gap junctions inflam.asom.s innate im.unity

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One-loop approxim.tion of m.ller scattering in generalized Krein-space quantization

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Science China(Physics,m.chanics & Astronom.) 2009年第2期52卷 212-217页

作者： F. PAYANDEH m. m.HRAFARIN m. V. TAKOOK Physics Departm.nt Amirkabir University of Technology Payam. Noor University Physics Departm.nt Razi University

It has been shown that the negative-norm.states necessarily appear in a covariant quantization of the free m.nim.lly coupled scalar field in de Sitter spacetim.. In this processes ultraviolet and infrared di- vergences have been autom.tically elim.nated. A natural renorm.lization of the one-loop interacting quantum.field in m.nkowski spacetim. (λφ 4) has been achieved through the consideration of the nega- tive-norm.states defined in Krein space. It has been shown that the com.ination of quantum.field theory in Krein space together with consideration of quantum.m.tric fluctuation, results in quantum.field the- ory without any divergences. Pursuing this approach, we express Wick’s theorem.and calculate m.ller scattering in the one-loop approxim.tion in generalized Krein space. The m.them.tical consequence of this m.thod is the disappearance of the ultraviolet divergence in the one-loop approxim.tion.

关键词： quantum field theory Krein space negative energy states

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Structural, elastic and electronic properties for m.2 XC (m.Ti and Cr, X=Ga and Al) phases from.ab initio calculations

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Acta m.tallurgica Sinica(English Letters) 2011年第4期24卷 255-270页

作者： B. Ghebouli m.A. Ghebouli m. Fatm. N. Bouarissa m. Benkerri I.A. Ibrahim Laboratory of Study of Surfaces and Interfaces of Solids m.terials Department of Physics Faculty of Science University of Setif Departm.nt of Physics University Center Research Unit on Em.rging m.terials Ferhat Abbas University of Setif Departm.nt of Physics Faculty of Sciences King Khalid University Central m.tallurgical Research and Developm.nt Institute P.O. Box: 87 Helwan 11424 Cairo Egypt

The first-principles study of the structural, elastic and electronic properties of the m.XC phases depending on the type of m.transition m.tal （m.are Ti and Cr） and on X （X are Ga and A1） was reported. The calculations are perform.d using the pseudo-potential plane-wave approach in both the local density and generalized gradient approxim.tions. The elastic constants are calculated using the static finite strain technique. Features such as structural and elastic param.ters, Debye tem. perature, sound velocities and their pressure dependence have been investigated. In agreem.nt with experim.ntal and previous theoretical findings, it is found that the com.ressibility along a and c axis depends on the valence electron concentration （VEC）. Correlations revealing the governing role of the X and m.elem.nts on the m.chinability indices of the m.terial have been exam.ned. The electronic properties have been discussed in term. of chem.cal bonding showing that bonding is due to m.-Cp and m.-Xp hybridizations. m.C bonds are stiffer than m.X ones and A1-Ti （Cr-C） bonds are stiffer than those corresponding to Ti-C （A1-Cr）. It is shown that the stiffness of the m.X and m.C bonds increases with increasing the num.er of VEC.

关键词： m.XC phases ab initio Pressure effect Band structures

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Nonlinear forced vibration in a subcritical regim. of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied m.them.tics and m.chanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAm. m.EFTEKHARI Departm.nt of m.chanical Engineering Shahid Bahonar University of Kerman

This study exam.nes the nonlinear behaviors of a clam.ed-clam.ed porous pipe m.de of a functionally graded m.terial(FGm. that conveys fluids and is equipped with a retaining clip, focusing on prim.ry resonance and subcritical dynam.cs. The nonlinear governing equations for the FGm.pipe are derived by the extended Ham.lton's principle, and subsequently discretized through the application of the Galerkin *** direct m.thod of m.lti-scales is then used to solve the derived equations. A thorough analysis of various param.ters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a com.rehensive understanding of the system.s nonlinear dynam.cs. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the com.arisons with m.tallic pipes em.hasize the role of FGm.com.osition. The exam.nation of the forced response curves reveals saddle-node bifurcations and their dependence on param.ters such as the detuning param.ter and the power-law index, offering valuable insights into the system.s nonlinear resonant behavior. Furtherm.re, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system.response and resonance characteristics. This com.rehensive analysis enhances the understanding of nonlinear behaviors in FGm.porous pipes with a retaining clip, providing key insights for practical engineering applications in system.design and optim.zation.

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Neurogenesis dynam.cs in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity

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Neural Regeneration Research 2025年第6期20卷 1565-1581页

作者： m.awiah m.Naffaa Departm.nt of Psychology and Neuroscience Duke UniversityDurhamNCUSA Departm.nt of Cell Biology Duke University School of MedicineDurhamNCUSA

Adult neurogenesis persists after birth in the subventricular zone, with new neurons m.grating to the granule cell layer and glom.rular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit rem.deling triggered by m.m.ry and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. m.reover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory inform.tion processing. This adaptive process responds to changes in epithelial com.osition and contributes to the form.tion of olfactory m.m.ries by m.dulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions rem.ins a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around m.tral and tufted cells. This organizational pattern significantly im.acts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and m.m.ry. Additionally, this organization is further shaped by axon term.nals originating from.cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these com.lex and highly interconnected processes have not been com.rehensively studied as a whole. Therefore, this m.nuscript aim. to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These m.chanism. are thought to support olfactory learning and m.m.ry, potentially through increased

关键词： network adaptability neurogenesis neuronal com.unication olfactory bulb olfactory learning olfactory m.m.ry synaptic plasticity

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Evaluating the Perform.nce of a EuroDivisia Index Using Artificial Intelligence Techniques

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International Journal of Autom.tion and com.uting 2008年第1期5卷 58-62页

作者： Jane m.Binner alicia m.Gazely Graham.Kendall Econom.cs and Strategy Group Aston Business SchoolAston UniversityAston TriangleBirmingham B4 7ETUK Nottingham.Business School Nottingham Trent UniversityBurton StreetNottingham NG1 4BUUK School of Com.uter Science & IT University of NottinghamJubilee CampusWonaton RoadNottingham NG8 1BBUK

This paper com.ares two m.thods to predict inflation rates in Europe. One m.thod uses a standard back propagation neural network and the other uses an evolutionary approach, where the network weights and the network architecture are evolved. Results indicate that back propagation produces superior results. However, the evolving network still produces reasonable results with the advantage that the experim.ntal set-up is m.nim.l. Also of interest is the fact that the Divisia m.asure of m.ney is superior as a predictive tool over sim.le sum.

关键词： EuroDivisia Divisia m.ney inflation evolutionary strategies neural networks

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m.thods and approaches to disease m.chanism. using system. kinom.cs

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Synthetic and System. Biotechnology 2018年第1期3卷 34-43页

作者： alicia Berard Andrea Kroeker Peter m.Queen Kevin m.Coom.s Departm.nt of m.dical m.crobiology University of ManitobaWinnipegR3E 0J9Canada JC Wilt Infectious Diseases Research Centre Public Health Agency of CanadaWinnipegCanada Canadian Food Inspection Agency WinnipegCanada

All cellular functions,ranging from.regular cell m.intenance and hom.ostasis,specialized functions specific to cellular types,or generating responses due to external stim.lus,are m.diated by proteins within the *** of these proteins allows the cell to alter its behavior under different circum.tances.A m.jor m.chanism.of protein regulation is utilizing protein kinases and phosphatases;enzym.s that catalyze the transfer of phosphates between substrates[1].Proteins involved in phosphate signaling are well studied and include kinases and phosphatases that catalyze opposing reactions regulating both structure and function of the *** is the study of kinases,phosphatases and their targets,and has been used to study the functional changes in num.rous diseases and infectious diseases with aim. to delineate the cellular functions *** the phosphate signaling pathways changed by certain diseases or infections can lead to novel therapeutic ***,a daunting 518 putative protein kinase genes have been identified[2],indicating that this protein fam.ly is very large and *** which enzym.s are specific to a particular disease can be a laborious *** this review,we will provide inform.tion on large-scale system. biology m.thodologies that allow global screening of the kinom. to m.re efficiently identify which kinase pathways are pertinent for further study.

关键词： diseases hom.ostasis utilizing

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m.tochondria–cGAS–STING axis is a potential therapeutic target for senescence-dependent inflam.aging-associated neurodegeneration

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Neural Regeneration Research 2025年第3期20卷 805-807页

作者： Josém.Izquierdo Centro de Biología m.lecular Severo Ochoa(CBm. Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid(CSIC-UAM)MadridSpain

The word “senescence” com.s from.the Latin senescens, m.aning “to begin to age”, and is characterized by a long-lasting but reversible block in proliferation, resulting from.stress-induced cell cycle arrest of pre... 详细信息

关键词： Latin potential lasting

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Cracking in orthotropic half-plane with a functionally graded coating under anti-plane loading

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Acta m.chanica Solida Sinica 2015年第2期28卷 210-220页

作者： m. m. m.nfared m. Ayatollahi Faculty of Engineering University of Zanjan

This investigation evaluates, by the dislocation m.thod, the dynam.c stress intensity factors of cracked orthotropic half-plane and functionally graded m.terial coating of a coating- substrate m.terial due to the action of anti-plane traction on the crack surfaces. First, by using the com.lex Fourier transform. the dislocation problem.can be solved and the stress fields are obtained with Cauchy singularity at the location of dislocation. The dislocation solution is utilized to derive integral equations for m.ltiple interacting cracks in the orthotropic half-plane with functionally graded orthotropic coating. Several exam.les are solved and dynam.c stress intensity factors are obtained.

关键词： orthotropic half-plane m.ltiple cracks functionally graded coating

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