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Male-like testosterone levels inhibit oviposition in a female parrot： A breeding experiment in budgerigars

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Current Zoology 2015年第4期61卷 586-595页

作者： Stefanie E. R LAHAYE Marcel EENS Veerle M. DARRAS Rianne PINXTEN University of Antwerp Research Group Ethology Antwerp Belgium KU Leuven Laboratory of Comparative Endocrinology B-3000 Louvain Belgium

Studies in several songbird species have shown that treating females with the androgenic steroid hormone testoste- rone （T） can negatively affect female reproductive behaviors and breeding success. As the effects of T on females appear to be species-specific, it is not clear if similar effects of high T occur in non-songbird species. Here, we studied the effects of T supplementation on female reproductive behavior and oviposition in the budgerigar, Melopsittacus undulatus, a small monogamous parrot species with distinct sex differences in parental behavior. We experimentally increased T concentrations to male-like levels in T-treated females compared to controls and we allowed females to breed. We found no significant effects of treatment on the latency to enter the nestbox but T treatment significantly interfered with oviposition. Our results show that T-treated females were seven times less likely to produce a clutch than control females. As we found that T treatment had a strong inhibitory effect on oviposition, our results indicate that female budgerigars suffer fitness costs from male-like plasma T levels. Therefore, it may be possible that, also in non-songbird species, selection for higher T levels in males is constrained by a correlated response to selection which imposes fitness costs on females in terms of reproduction. Evaluating whether or not this is indeed the case requires further work combining different approaches to the study of the evolution of male and female testosterone levels [Current Zoology 61 （4）： 586-595, 2015].

关键词： Female testosterone Reproductive behavior Melopsittacus undulatus Breeding success Intralocus sexual conflict Antagonistic selection

In situ IR-RAS investigation of corrosion of tin in air containing H_2O, NO_2 and SO_2 at room temperature

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Journal of University of Science and Technology Beijing 2003年第3期10卷 35-38页

作者： SasakiTakeshi KanagawaRyoji OhtsukaToshiaki Research group of Interface Control Engineering Graduate School of EngineeringHokkaido UniversitySapporo 060-8628JapanResearch Group of Interface Control EngineeringGraduate School of EngineeringHokkaido UniversitySapporo 060-8628JapanResearch Group of Interface Control EngineeringGraduate School of EngineeringHokkaido UniversitySapporo 060-8628Japan

In order to obtain a fundamental understanding of the corrosion behavior oftin in atmosphere, in situ IR-RAS (infrared reflection absorption spectroscopy) measurements wereperformed on tin in humid air containing SO_2 and NO_2 at room temperature. Time-resolved in situ IRspectra in air of 90 percent RH (relative humidity) containing 1 X 10^(-5)-2.2 X 10^(-5) SO_2suggested that the tin oxide layers worked as a protective film and no significant corrosionoccurred. The corrosion products in air of 80 percent-90 percent RH containing 1 X 10^(-5)-2.2 X10^(-5) NO_2 were SnO_2, SnO, nitrate and hyponitrite. The synergistic effect of SO_2 and NO_2 oncorrosion of tin was not observed in air of 90 percent RH containing 0.84 X 10^(-6) SO_2 and 1.8 X10^(-6) NO_2.

关键词： Corrosion of tin in a gaseous environment in situ IR-RAS

Monte Carlo study of B-cell receptor clustering mediated by antigen crosslinking and directed transport

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Cellular & Molecular Immunology 2011年第3期8卷 255-264页

作者： A Srinivas Reddy Philippos K Tsourkas Subhadip Raychaudhuri Department of Biomedical Engineering University of California DavisDavisUSA Biophysics graduate group University of California DavisDavisUSA graduate group in Applied Mathematics University of California DavisDavisUSA

It is known from experiments that in the presence of soluble antigen,B-cell receptors(BCRs)assemble into microclusters and then collect into a macrocluster known as a‘cap’.However,the mechanisms of BCR cluster formation during recognition of soluble antigens remain *** previous work,we demonstrated that effective intrinsic attractions among BCRs can lead to the formation of small microclusters of BCR *** effective intrinsic attractions could be caused by multivalent antigen binding,association with lipid rafts,or other biochemical *** the present study,we have developed and studied a Monte Carlo model of BCR clustering mediated by explicit binding and crosslinking of soluble bivalent *** crosslinking is shown to microcluster BCRs in an affinity-dependent manner and also in a biologically relevant timescale;however,antigen crosslinking alone does not appear to be sufficient for the formation of a single macrocluster of receptor *** show that directed transport of BCRs is needed to drive the formation of large *** constructed a simple model of directed transport,where BCR molecules diffuse towards the largest cluster or towards a random BCR microcluster,which results in a single macrocluster of receptor *** mechanisms for both types of directed transport are compared using network-based *** also develop and use appropriate network measures to analyze the effect of BCR and antigen concentration on BCR clustering,the stability of the formed clusters over time and the size of BCR–antigen crosslinked chains.

关键词： B-cell activation B-cell receptor cell signaling Monte Carlo simulation receptor clustering

Central role of the LEAFY COTYLEDON1 transcription factor in seed development

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Journal of Integrative Plant Biology 2019年第5期61卷 564-580页

作者： Leonardo Jo Julie M.Pelletier John J.Harada Department of Plant Biology and Plant Biology graduate group University of CaliforniaDavis USA

Seed development is a complex period of the flowering plant life *** fertilization,the three main regions of the seed,embryo,endosperm and seed coat,undergo a series of developmental processes that result in the production of a mature seed that is developmentally arrested,desiccated,and metabolically *** processes are highly coordinated,both temporally and spatially,to ensure the proper growth and development of the *** transcription factor,LEAFY COTYLEDON1(LEC1),is a central regulator that controls several aspects of embryo and endosperm development,including embryo morphogenesis,photosynthesis,and storage reserve ***,LEC1 regulates distinct sets of genes at different stages of seed *** its critical importance for seed development,an understanding of the mechanisms underlying LECi's multifunctionality is only beginning to be *** studies describe the roles of specific transcription factors and the hormones,gibberellic acid and abscisic acid,in controlling the activity and transcriptional specificity of LEC1 across seed ***,studies indicate that LEC1 acts as a pioneer transcript!on factor to promote epigenetic reprogramming during *** this review,we discuss the mechanisms that enable LEC1 to serve as a central regulator of seed development.

关键词： Seed development flowering plant seed development

An area-saving dual-path loop filter for low-voltage integrated phase-locked loops

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Journal of Semiconductors 2009年第10期30卷 115-120页

作者：潘杰杨海钢杨立吾 Institute of Electronics Chinese Academy of Sciences graduate University of the Chinese Academy of Sciences RF Application group SMIC

This paper proposes an area-saving dual-path loop filter（LPF）for low-voltage integrated phase-locked loops（PLLs）.With this LPF,output current of the lowpass-path charge-pump（CP）is B times（B〉1）as great as that of the integration-path *** adding voltages across these two paths,the zero-capacitance is magnified B times *** a result,the chip size is greatly *** on this LPF,a 1.2 V 3.5 GHz-band PLL is fabricated in SMIC 0.18μm RFCMOS *** zero-capacitance is only 1/30 of that in conventional second-order LPFs. Measured data show that,at a frequency of 3.20 GHz,phase noise is–120.2 dBc/Hz at 1 MHz offset,reference spur is–72 dBc,and power is 24 mW.

关键词： area-saving dual-path loop filter charge-pump phase-locked loop

A simple method of measuring differentially-excited on-wafer spiral inductor-like components

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Journal of Semiconductors 2009年第7期30卷 62-66页

作者：潘杰杨海钢杨立吾 Institute of Electronics Chinese Academy of Sciences graduate University of the Chinese Academy of Sciences RF Application group SMIC

This paper proposes a simple method of measuring differentially-excited on-wafer RF CMOS spiral inductor-like *** method requires only two common ‘G-S-G＇ probes and an ordinary two-port *** a network instead of a detailed equivalent circuit, this method completes the de-embedding with only one ‘Through＇ dummy, and thus the measurements are greatly *** designing the ports ‘Open＇ or ‘Shortcircuited＇ deliberately, a multi-port transformer can be transformed into three two-port networks with different ***, couplings between the two coils can be solved, and the differentially-excited scattering parameters（S-parameters） can be ***, a group of differential inductors and transformers were designed and measured, and then comparisons between simulated and measured electromagnetic results are performed to verify this method.

关键词： on-wafer differentially-excited de-embedding two-port network S-parameter

Contribution of molecular cladistics to the taxonomy of Rutaceae in China

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Journal of Systematics and Evolution 2009年第2期47卷 144-150页

作者： Paul Pui-Hay BUT Alice Wing-Sem POON Pang-Chui SHAW Mark P.SIMMONS Harald GREGER Department of Biology Chinese University of Hong Kong Department of biochemistry Chinese University of Hong Kong Department of Biology Colorado State UniversityFort Collins comparative and Ecological Phytochemistry Faculty Center of BotanyUniversity of Vienna

The treatment of Rutaceae in the Chinese flora chose to follow Engler in recognizing Rutoideae and Toddalioideae as two separate *** and chemical comparisons,however,suggested group-ing those two subfamilies in one subfamily,*** move has received support from molecular phyloge-netic analyses,which also showed that the Chinese taxa in Euodia should be placed in Tetradium and Melicope following *** into the chemistry and molecular phylogeny of Murraya also indicated that the species in the section Bergera without yuehchukene should be removed from *** findings clearly show the value of molecular cladistics to the taxonomy of Rutaceae in China and also directions for further inves-tigations.

关键词： Bergera Euodia Melicope Murraya Rutaceae Rutoideae Tetradium Toddalioideae

On the Model for the Reform of China's Economic Structure

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Social Sciences in China 1985年第1期 9-33+5页

作者： group for the comparative Study of Economic Structures Zhao Qinghua group for the comparative Study of Economic Structures

is a report on com- parative studies into the models for socialist *** divides socialist economiesinto five models:the supply system of war communism,the traditional centralizedplanned economy,the revised centralized planned economy,the planned economy com-bining regulation by plan and the market mechanism,and the socialist market *** authors believe that economic reform is aimed at changing the basic speci-fications and principles of motion of the economic system and mark a transition fromone economic model to *** into the model for China’s economicreform must proceed from the conditions in this country while conscientiously sum-ming up the experience and lessons gained from the evolution of China’s economicsystem since the founding of the People’s *** this as a foundation,China’s economic reform should—on the basis of upholding socialist public owner-ship and the principle of distribution according to work—create a model that issuited to a vigorous development of commodity production and exchange and bene-ficial to consolidating the planned economic *** feel that a planned econ-omy that organically combines regulation by plan with the market mechanism may bethe most suitable model for *** writing of this research report was coordinat-ed by Liu *** Jinglian,Chen Jiyuan,Rong Jingben,Lin Qinsong,KongDan and Sun Xuewen participated in the discussions and in drafting part of the *** Jiyuan,Rong Jingben and Lin Qinsong have done most of the actualwriting.

关键词： On the Model for the Reform of China’s Economic Structure

Epigenomic reprogramming in peripheral nerve injury

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Neural Regeneration Research 2016年第12期11卷 1930-1931页

作者： Ki H.Ma John Svaren Waisman Center University of Wisconsin-Madison Cellular and Molecular Pathology graduate Program University of Wisconsin-Madison Department of comparative Biosciences University of Wisconsin-Madison

The regenerative capacity of peripheral nerve is significantly different from injury responses in the central nervous *** of injured axons,re-myelination and functional recovery are readily observed after injury to pe... 详细信息

关键词： gene cell Epigenomic reprogramming in peripheral nerve injury