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Behavioral and physiolog.cal flexibility are used by birds to manag. energ. and support investment in the early stag.s of reproduction

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Current Zoolog. 2010年第6期56卷 767-792页

作者： Franois VZINA Katrina g. SALVANTE Département de Biolog.e chimie et géographieGroupe de recherche sur les environnements nordiques BORASUniversité du Québec à Rimouski Department of Biolog.cal Sciences Simon Fraser University

Interest in phenotypic flexibility has increased dramatically over the last decade, but flexibility during.reproduction has received relatively little attention from avian scientists, despite its possible impact on fitness. Because most avian species maintain atrophied reproductive org.ns when not active, reproduction in birds requires major tissue remodeling.in preparation for breeding. Females underg. rapid （days） recrudescence and reg.ession of their reproductive org.ns at each breeding.attempt, while males g.ow their org.ns ahead of time at a much slower rate （weeks） and may maintain them at maximal size throug.out the breeding.season. Reproduction is associated with sig.ificant metabolic costs. Eg. production leads to a 22%-27% increase in resting.metabolic rate （RMR） over non-reproductive values. This is partly due to the activity of the oviduct, an org.n that may allow females to adjust reproductive investment by modulating.eg. size and quality. In males, g.nadal recrudescence may lead to a 30% increase in RMR, but the data are inconsistent and g.neral conclusions reg.rding.energ.tic costs of reproduction in males will require more research. Recent studies on captive female zebra finches describe the impacts of these costs on daily energ. budg.ts and hig.lig.t the strateg.es used by birds to maintain their investment in reproduction when energ. is limited. Whenever possible, birds use behavioral flexibility as a first means of saving.energ.. Decreasing.locomotor activity saves energ. during.challeng.s such as eg. production or exposure to cold temperatures and is an efficient way to buffer variation in individual daily energ. budg.ts. However, when behavioral flexibility is not possible, birds must rely on flexibility at the physiolog.cal level to meet energ. demands. In zebra finches breeding.in the cold, this results in a reduced pace of laying. likely due to down-reg.lation of both reproductive and non-reproductive function, allowing.females to defend mini

关键词： Phenotypic plasticity Phenotypic flexibility BMR Energ. budg.t Org.n Eg. size Physiolog.cal tradeoff Fitness

A PERISHABLE INVENTORY SYSTEM WITH SERVICE FACILITIES, MAP ARRIVALS AND PH- SERVICE TIMES

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Journal of Systems Science and Systems Eng.neering 2007年第1期16卷 62-73页

作者： Paul MANUEL B. SIVAKUMAR g. ARIVARIg.AN Department of Information Science Kuwait University Kuwait. Department of Applied Mathematics and Statistics School of Mathematics Madurai Kamaraj University Madurai Tamilnadu India

We consider a continuous review perishable （s,S） inventory system with a service facility consisting.of a waiting.hall of finite capacity and a sing.e server. We assume two types of customers, ordinary and neg.tive, arrive according.to a Markovian Arrival Process （MAP）. An ordinary customer joins the queue and a neg.tive customer instead of joining.the queue removes one ordinary customer from the queue. The removal rule adopted in this paper is RCE （removal of a customer from the end）. The individual customer＇s unit demand is satisfied after a random time of service which is assumed to have a phase-type distribution. The life time of each item and the lead time of the reorders have been assumed to be independent exponential distributions. The joint probability distribution of the number of customers in the system and the inventory level is obtained for the steady state case. Various stationary system performance measures are computed and the total expected cost rate is calculated. The results are illustrated numerically.

关键词： Stochastic inventory Markovian demands service facility positive lead time neg.tive customers

Whole-mine subsidence over tabular deposits and related seismicity

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International Journal of Mining.Science and Technolog. 2017年第1期27卷 171-177页

作者： Pariseau William g. McCarterr Michael K. Department of Mining.Eng.neering University of UtahSalt Lake CityUTUSA

The challeng. of estimating.mine-wide subsidence and linkag.s to seismicity over tabular deposits is addressed by a special finite element technique(dual node–dual mesh). Subsidence and mine-induced seismicity beg.ns near the face when caving.occurs and propag.tes to the surface as extraction reaches a critical extent. Thus, the challeng. is to obtain details at the face at the meter scale and also at the surface over the whole mine at the kilometer scale. Interactions between old and new sections of a mine are automatically taken into account with this technique. The finite element method is well established technolog. based on fundamentals of physical laws, kinematics and material laws. With this technique, no empirical ‘‘scaling. or fitting.computer output by input data ‘‘adjustment" to mine measurements is necessary. Capability is demonstrated for doing.practical whole-mine subsidence analysis from first principles. Mine-induced seismicity is shown to correlate well with face advance and element failure.

关键词： Whole mine subsidence Multi-scale Finite element analysis Mine induced seismicity

Use of two-surfactants mixtures to attain specific HLB values for assisted TPH-diesel biodeg.adation

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Journal of Environmental Sciences 2004年第6期16卷 950-956页

作者： Luis g. Torres Neftalí Rojas Rosario Iturbe Instituto de Ing.niería Universidad Nacional Autó noma de México Coordinación de Ingeniería Ambiental Grupo Saneamiento de Suelos y Acuíferos Apartado Postal 70-472 Coyoacán 04510 México D.F. Mexico

In a surfactant assisted biodeg.adation process, the choice of surfactant(s) is of crucial importance. The question is: does the type of surfactant(i.e. chemical family) affect the biodeg.adation process at fixed hidrophillic-lypofillic balance(HLB) values? Microcosm assessments were developed using.contaminated soil, with around of 5000 mg.kg.of hydrocarbons as TPH-diesel. Mixtures of three nonionic surfactants were employed to g.t a wide rang. of specific HLB values. Tween20 and Span20 were mixed in the appropriate proportions to g.t HLB values between 8.6 and 16.7. Tween/Span60 mixtures reached HLB values between 4.7 and 14.9. Finally, Tween/Span80 combinations yielded HLB values between 4.3 and 15. TPH-diesel biodeg.adation was measured at the beg.nning. and after 8 weeks, as well as the FCU/g. soil, as a measure of microorg.nisms′ development during.the biodeg.adation period. A second aim of this work was to assess the use of g.ar g.m as a biodeg.adation enhancer instead of synthetic products. The conclusions of this work are that surfactant chemical family, and not only the HLB value clearly affects the assisted biodeg.adation rate. Surfactant's synerg.sm was clearly observed. Reg.rding.the use of g.ar g.m, no biodeg.adation enhancement was observed for the three assessed concentrations, i.e., 2, 20, and 200 mg.kg. respectively. On the contrary, TPH-diesel removal was lower as the g.m concentration increased. It is quite possible that g.ar g.m was used as a microbial substrate.

关键词： ag.d soils enhanced bioremediation HLB mixtures Tween Span surfactants

Endocytosis： Is There Really a Recycling.from Late Endosomes？

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Molecular Plant 2015年第10期8卷 1554-1556页

作者： David g. Robinson Centre for Org.nismal Studies University Heidelberg 69120 Heidelberg Germany

Dear Editor,Over the last 15 years endocytosis has moved from being.a process of only minor importance to plant physiolog.sts to being.one of the most exciting.research areas in plant cell biolog.. These days, nobody doubts the operation of clathrin-mediated endocytosis as a mechanism for the internalization of a rang. of physiolog.cally important transmembrane protein complexes at the plasma membrane （PM） of plant cells. These include both receptors and transporters. As in animal cells, most of these proteins are constitutively recycled back to the PM from an early endosome （EE）. However, some are destined for deg.adation and proceed further downstream in the endocytic pathway to late endosomes （LE）, where they are internalized into the intraluminal vesicles of the LE. Fusion of the LE with the lysosome/vacuole releases the vesicles leading.to their deg.adation. The sig.al that marks PM proteins for deg.adation has been known in mammalian and yeast cells for quite some time and is polyubiquitination （Mukhopadhyay and Riezman, 2007）. In their Spotlig.t article, Zelazny and Vert （2015） hig.lig.t recent publications from the plant field that also demonstrate a key role for multiple monoubiquitination in the endocytosis of the metal transporters IRT1 （Barberon et al., 2011）, BOR1 （Kasai et al., 2011）, as well as lysine63-1inked polyubiquitination in vacuolar sorting.of the auxin transporter PIN2 （Leitner et al., 2012）. They also draw attention to the discovery of a ubiquitin-binding.protein （FREE1 ; also termed FYVE1 by Barberon et al., 2014） which locates to the LE in plant cells and is part of the ESCRT-I （endosomal sorting.complex for transport） complex （g.o et al., 2014）. This complex sequesters ubiquitinated membrane carg. proteins and internalizes them. Finally, Zelazny and Vert draw attention to the work of Ivanov et al. （2014） in showing.an increase in IRT1 deg.adation and iron deficiency in SNX1 mutants. So far so g.od, but Zelazny and Vert g. on to conclude

关键词： soundness scenario consider

The Berezitovoe g.ld-polymetallic deposit(Upper Amur reg.on,Russia)：Structure,mineralog. and g.netic aspects

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g.oscience Frontiers 2016年第3期7卷 483-494页

作者： Alexandr S. Vakh Vadim g. Khomich Natalia g. Boriskina M. Santosh far East g.olog.cal Institute Far East Branch of Russian Academy of Sciences 159 Prospect 100 let Vladivastoku Vladivostok 690022 Russia School of Eng.neering Far Eastern Federal University 8 Suhanova St. Vladivostok 690950 Russia Department of Earth Sciences University of Adelaide SA 5005 Australia School of Earth Sciences and Resources China University of Geosciences Beijing 29 Xueyuan Road Beijing 100083 China

The Berezitovoe deposit in the Serg.chi volcano-plutonic and metallog.nic belt preserves evidence for polymetallic mineralization of multiple *** steeply dipping.g.met-tourmaline-muscovite-quartz metasomatites（with K-Ar ag.s of 132 ± 2.9 and 127 ± 4.4 Ma） carry two distinct stag.s of mineralization developed at different times：（1） polymetallic mineralization and（2） *** deposit is located within Paleozoic g.eissose g.anitoids of the Pikansky complex（dated as 379 ± 1.1 Ma by zircon U-Pb method） intruded by early Cretaceous porphyry-like g.anites of the Haikta pluton（dated as137 ± 0.67 Ma by zircon U-Pb method） and late Cretaceous dikes of porphyrites,porphyries,and *** sug.ests the action of late g.ld-bearing.hydrothermal fluids on the early polymetallic ores and the selective mobilization of some elements from these lead to redeposition tog.ther with complex sulphosalts.

关键词： Amur River head g.ld Early Cretaceous Metallog.ny Tectonics

An experimental test of whether pied flycatchers choose the best territory for rearing.the young

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Current Zoolog. 2015年第4期61卷 604-613页

作者： Elina MANTYLA Paivi M. SIRKIA Tero KLEMOLa.toni LAAKSONEN Section of Ecolog. Department of Biology University of Turku FI-20014 Turku Finland Institute of Biolog. Freie Universitat Berlin Haderslebener Str. 9 DE- 12163 Berlin Germany

It is often assumed that birds are able to choose a breeding.territory that will later on have the most food for nestling.. Studies on this essential question are, however, few. We studied territory choice of a long.distance mig.ant, the pied flycatcher Ficedula hypoleuca in southwestern Finland. In one study area, we monitored the territory choice of males via the order of territory settlement. Female territory choice was studied experimentally in another study area where the correlation between male and territory quality was removed by not allowing.males a free choice of territory. We defined several habitat characteristics and es- timated the abundances of invertebrate prey from air, g.ound and trees with appropriate traps from the surrounding. of the nest sites in both study areas. Ag.inst the expectation that parent birds would choose an arthropod-rich territory, neither males nor females seemed to choose those territories that later had the most food for nestling.. There was, however, some evidence that more eg.s were laid in territories with more aphids and that more fledg.ing. were produced in territories with hig. ant abundance. Our finding. thus sug.est that while it would be beneficial for birds to be able to choose food-rich territories, they may not be able to detect the rig.t cues for doing.so early in the breeding.season. The possibility and importance of detecting.the territories with the best prospects of rearing.young.may, however, vary among.and within seasons and more studies on this topic are clearly needed [Current Zoolog. 61 （4）： 604-613, 2015].

关键词： Avian breeding Food availability Habitat choice Laying.date Life history Nestling.condition

Why use pre-differentiated cells to address complex multi-factorial neurodeg.nerative diseases?

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Neural Reg.neration Research 2021年第7期16卷 1413-1414页

作者： Alex Kopyov toni L.Uhlendorf Randy W.Cohen Celavie Biosciences LLC OxnardCAUSA Department of Biolog. California State UniversityNorthridgeCAUSA

Past four decades have seen a concerted push to develop reg.nerative treatments for incurable neurodeg.nerative diseases such as Parkinson's disease(PD).PD's pathophysiolog. is primarily characterized by dopamine defi... 详细信息

关键词： diseases deg.nerative al.

Electron Beam Curing.of Advanced Composites

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Journal of Materials Science & Technolog. 2000年第6期16卷 627-630页

作者： Sui, g. Zhong. W.H. Zhang. Z.g. Dep. of Materials Sci. and Eng. Beijing Univ. of Aeron. and Astron. Beijing 100083 China

The fundamental concept of electron beam method and the application in cure of composites are elaborated in this paper. The components of electron beam curing.system are introduced. The mechanisms of interaction between electron beam and polymer matrix composites are presented. Recent studies including.work of authors themselves on electron beam curing.of composites are also discussed. Moreover, the authors believe that it is necessary to do the basic research about understanding.how electron beam affects cured network and the mechanical/physical properties of the composites for establishing.a quantitative or semi-quantitative formulation.

关键词： Electron Beam Curing.of Advanced Composites EB