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To forage or hide？ Threat-sensitive foraging behaviour in wild, non-reproductive passerine birds

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current Zoology 2014年第6期60卷 719-728页

作者： Shaun TURNEY jean-Guy j. GODIN Department of Biology Carleton University Ottawa ON K1 S 5B6 Canada Department of Biology McGill University Montreal QC H3A 1B 1 Canada

Because antipredator behaviours are costly, the threat-sensitive predator avoidance hypothesis predicts that individual animals should express predator-avoidance behaviour proportionally to the perceived threat posed by the predator. Here, we experimentally tested this hypothesis by providing wild passerine birds supplemental food （on a raised feeding platform） at either 1 or 4 m from the edge of forest cover （potential refuge）, in either the presence or absence of a nearby simulated predation threat （a sharp-shinned hawk Accipiter striatus model）. compared with the control treatment, we observed proportionally fewer bird visits to the food patch, and the birds took longer to re-emerge from forest refuge and return to feed at the food patch, after the hawk presentation than before it. The observed threat-sensitive latency-to-return response was stronger when the food patch was further away from the nearest refuge. Overall, our results are consistent with the predictions of the threat-sensitive predator avoidance hypothesis in that wild passerine birds （primarily black-capped chickadees Poecile atricapillus） exhibited more intense antipre- dator behavioural responses with increasing level of apparent threat. The birds were thus sensitive to their local perceived threat of predation and traded-off safety from predation （by refuging） and foraging gains in open habitat in a graded, threat-sensitive manner [current Zoology 60 （6）： 719-728, 2014].

关键词： Foraging Predation risk Threat sensitivity Risk taking Distance-to-refuge Birds

A review of the effects of dietary organic acids fed to swine

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journal of Animal Science and Biotechnology 2016年第1期7卷 67-77页

作者： Mocherla V A N Suiryanrayna j V ramana Livestock Research Station Sri Venkateswara Veterinary University

Animal production depends on nutrient utilization and if done there is an accelerated momentum towards growth with a low cost to feed ratio Public concern over the consumption of pork with antibiotic residues of the animals fed with antibiotic growth promoters （AGP） has paved the way to use other additives like herbs and their products, probiotics, prebiotics etc. Numerous feed additives are in vogue for achieving this target and one such classical example is the usage of organic acids and their salts. Usage of organic acids was in progress for over four decades. Early weaned piglets are （3-4 weeks age） exposed to stress with a reduced feed intake, little or no weight gain. This post weaning lag period is due to a limited digestive and absorptive capacity due to insufficient production of hydrochloric acid, pancreatic enzymes and sudden changes in feed consistency and intake. Lowering dietary pH by weak organic acids was found to overcome these problems. The main activity of organic acids is associated with a reduction in gastric pH converting the inactive pepsinogen to active pepsin for effective protein hydrolysis. Organic acids are both bacteriostatic and bactericidal. Lactic acid has been reported to reduce gastric pH and delay the multiplication of an enterotoxigenic E. coil These acids are the intermediary products in Kreb＇s cycle and thus act as an energy source preventing the tissue breakdown resulting from gluconeogenesis and lipolysis. Excretion of supplemental minerals and nitrogen are minimized with organic acids as these form complexes with minerals and aids for their bio-availability. Short chain fatty cids like acetic, propionic and n-butyric acid produced by microbial fermentation of dietary fibre in the large intestines may increase the proliferation of epithelial cells and have stimulatory effects on both endocrine and exocrine pancreatic secretions in pigs. Organic acids also enhances apparent total tract digestibility and improves growth performa

关键词： chelation Improved productivity Organic acids Pathogen inhibition Protein utility Swine

Recent insights into androgen action on the anatomical and physiological substrate of penile erection

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Asian journal of Andrology 2006年第1期8卷 3-9页

作者： Louis j.G.Gooren Farid Saad Department of Endocrinology Andrology SectionVrije Universiteit Medical Center1007 MB AmsterdamThe Netherlands Gulf Medical college Medical University of theUnited Arab Emirates2563 Ajman UAE Andrology DepartmentSchering AG13342 BerlinGermany

Erectile response is centrally and peripherally regulated by androgens. The original insights into the mechanisms of action of androgens were that androgens particularly exert effects on libido and that erections in response to erotic stimuli were relatively androgen-independent. It was shown that sexual functions in men required androgen levels at the low end of reference values of testosterone. So it seemed that testosterone was not useful treatment for men with erectile difficulties, particularly following the advent of the phosphodiesterase type 5 （PDE5） inhibitors. However, approximately 50% of those treated with PDE5 inhibitors discontinue their treatment. A number of recent developments shed new light on testosterone treatment of erectile dysfunction （ED） in aging men. （1） A recent insight is that, in contrast to younger men, elderly men might require higher levels of testosterone for normal sexual functioning. （2） Several studies have indicated that PDE5 inhibitors are not always sufficient to restore erectile potency in men, and that testosterone improves the therapeutical response to PDE5 inhibitors considerably. （3） There is growing insight that testosterone has profound effects on tissues of the penis involved in the mechanism of erection and that testosterone deficiency impairs the anatomical and physiological substrate of erectile capacity, reversible upon androgen replacement. The synthesis of PDE5 is upregulated by androgens, and the arterial inflow into the penis is improved by giving androgen. The above invites a re-examination of the merits of giving testosterone to aging men with ED. The beneficial effects of PDE5 inhibitors may only be optimally expressed in a eugonadal environment. （Asian j Androl 2006 jan; 8： 3-9）

关键词： testosterone erection corpus cavernosum phosphodiesterase type 5 inhibitors

Long-term monitoring of PcDD/PcDF and other unintentionally produced POPs-concepts and case studies from Europe

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Science china chemistry 2010年第5期53卷 1017-1024页

作者： REINMANN jürgen WEBER Roland HAAG Roland Environnement S.A Deutschland Benzstrasse 1161352 Bad HomburgGermany POPs Environmental consulting Ulmenstraβe 373035 GppingenGermany TüV Süd Industrie Service GmbH Grabenwiesenstraβe 473072 DonzdorfGermany

During the start-up and unstable combustion periods,even the state-of-the-art incinerators emit polychlorinated dibenzo-p-dioxins and dibenzofurans(PcDD/PcDF) in stack gases at concentrations that are up to 1000 times higher than normal operation. Therefore,incinerators and other sources with variation of PcDD/PcDF release into air cannot be reliably monitored by the conventional short-term sampling that covers only 0.1%to 0.2%of the yearly operating time.A more comprehensive monitoring regime is *** paper describes different applications of continuous PcDD/PcDF sampling in some European *** cases demonstrate that flexible regimes for continuous sampling can be crafted and applied by governments or regional/local *** regimes range from a countrywide,continuous requirement for selected facility types(e.g.,waste incinerators) to a facility-specific regime that applies,for example,to new facilities for a defined time period until the facility has demonstrated continuous compliance with regulatory limits. countries implementing the Stockholm convention are suggested to evaluate in their Best available technology/Best environmental practice(BAT/BEP) activities the usefulness of long-term sampling by,for example,designating institutes related to the environmental ministry or regional authorities to supervise long-term sampling regimes at relevant facilities in their country/areas,beginning with priority sources(e.g.,facilities used for destruction of persistent organic pollutants(POPs) or hazardous waste processing) . This paper presents and discusses the results of the AMESA long-term monitoring system having demonstrated that in addition to PcDD/PcDF all other unintentionally produced POPs listed in the Stockholm convention could be supervised.

关键词： PcDD/PcDF PcB continuous sampling unintentionally produced POPs Stockholm convention BAT/BEP

Gene-environment interactions in male reproductive health： special reference to the aryl hydrocarbon receptor signaling pathway

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Asian journal of Andrology 2014年第1期16卷 89-96页

作者： Leon j S Brokken Yvonne Lundberg Giwercman Department of clinical Sciences Molecular Genetic Reproductive Medicine Lund University MalmO Sweden

Over the last few decades, there have been numerous reports of adverse effects on the reproductive health of wildlife and laboratory animals caused by exposure to endocrine disrupting chemicals （EDcs）. The increasing trends in human male reproductive disorders and the mounting evidence for causative environmental factors have therefore sparked growing interest in the health threat posed to humans by EDcs, which are substances in our food, environment and consumer items that interfere with hormone action, biosynthesis or metabolism, resulting in disrupted tissue homeostasis or reproductive function. The mechanisms of EDcs involve a wide array of actions and pathways. Examples include the estrogenic, androgenic, thyroid and retinoid pathways, in which the EDcs may act directly as agonists or antagonists, or indirectly via other nuclear receptors. Dioxins and dioxin-like EDcs exert their biological and toxicological actions through activation of the aryl hydrocarbon-receptor, which besides inducing transcription of detoxifying enzymes also regulates transcriptional activity of other nuclear receptors. There is increasing evidence that genetic predispositions may modify the susceptibility to adverse effects of toxic chemicals. In this review, potential consequences of hereditary predisposition and EDcs are discussed, with a special focus on the currently available publications on interactions between dioxin and androgen signaling.

关键词： androgen receptor aryl hydrocarbon receptor endocrine disrupter

A review of development of better prediction equations for blast fragmentation

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journal of Rock Mechanics and Geotechnical Engineering 2019年第5期11卷 1094-1109页

作者： F.Ouchterlony j.A. Sanchidrián Department of Mining Engineering and Mineral Economics Montanuniversitaet Leoben Leoben Austria ETSI Minas Universidad Politécnica de Madrid Madrid Spain

The paper reviews the development of prediction formulas for the fragmentation from bench *** attention has been paid to the Kuz-ram model,its development and errors,and the mean *** *** work by the US Bureau of Mines(USBM)and chung and Katsabanis are also reviewed,as well as the two julius Kruttschnitt Mineral Research centre(jKMRc)models,*** crush zone model(cZM)and the two-component model(TcM),which were developed to cope with the underestimation of blasting *** change brought by the Swebrec distribution and the associated Kuznetsov-cunningham-Ouchterlony(KcO)model is *** distribution-free fragment sizes xP for an arbitrary mass passing P led to the discovery of the fragmentation-energy fan,and with the help of dimensional analysis,to the new fragmentation prediction model xP-frag,which has much lower errors than those of the Kuz-ram and cZM models.

关键词： Bench blasting Rock fragmentation Fragmentation model Size distribution Swebrec function Fragmentation-energy fan

A modified TreePM code

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Research in Astronomy and Astrophysics 2009年第8期9卷 861-873页

作者： Nishikanta Khandai j. S. Bagla Harish-chandra Research Institute

We discuss the performance characteristics of using the modification of the tree code suggested by Barnes in the context of the TreePM code. The optimization involves identifying groups of particles and using only one tree walk to compute the force for all the particles in the group. This modification has been in use in our implementation of the TreePM code for some time, and has also been used by others in codes that make use of tree structures. We present the first detailed study of the performance characteristics of this optimization. We show that the modification, if tuned properly, can speed up the TreePM code by a significant amount. We also combine this modification with the use of individual time steps and indicate how to combine these two schemes in an optimal fashion. We find that the combination is at least a factor of two faster than the modified TreePM without individual time steps. Overall performance is often faster by a larger factor because the scheme for the groups optimizes the use of cache for large simulations.

关键词： cosmology large-scale structure of universe -- gravitation -- methods numerical

RELATIONSHIP BETWEEN INFRARED RADIATION AND cRYSTAL STRUcTURE IN Fe-Mn-co-cu-O SPINELS

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Acta Metallurgica Sinica(English Letters) 2008年第1期21卷 15-20页

作者： Y. Zhang D.j. Wen School of Material Engineering Soochow University Suzhou 215021 China

Ni^3＋ and cr^3＋ doped Fe-Mn-co-cu-O spinels have been prepared by solid phase sintering. The valence states and distribution of transition ions in the spinel crystals are inferred by the consideration of thermodynamic principle and crystalline field theory. The mierostructure and performance of those are studied by X-ray diffraction （XRD）, Fourier transform infrared （FT-IR）, and IRE-2 infrared radiant instrument. Ni3＋ and cr3＋ occupy the vacancies or substitute the other ions in the spinel structures and form diverse spinel structures, which exhibit infrared integral emissivities of 0.93 in the whole band, and 0. 94 in the band within 14-25μm too. The content of Fe2O3 and MnO2 in the spinel crystals changes, maybe it induces infrared radiativity of spinels differently.

关键词： crystal structure Mineral Infrared radiation property

Haemovigilance and experience of the serlous hazards of transfusion(SHOT)scheme in the United Kingdom(UK)

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中国输血杂志 2001年第S1期14卷 206-210页

作者： EMLove Hjomes Williamson H cohen A Todd K Soldan j Revill D R Norfolk j Barbara c L j Atterbury DAsher On be half of the SHOT Steering Group On be half of the SHOT Steering GroupOn be half of the SHOT Steering GroupOn be half of the SHOT Steering GroupOn be half of the SHOT Steering GroupOn be half of the SHOT Steering GroupOn be half of the SHOT Stee