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Female mate choice and the potential for ornament evolution in túngara frogs Physalaemus pustulosus

Current Zoology 2010年第3期56卷 343-357页

作者： Michael J.RYAN Ximena E.BERNAL a.stanley rand Section of Integrative Biology C0930 University of Texas Smithsonian Tropical Research Institution Department of Biological Science Texas Tech University Srnithsonian Tropical Research Institution

The potential for ornament evolution in response to sexual selection rests on the interaction between the permissive- ness or selectivity of female preferences and the constraints on male development of signaling related traits. We investigate the former by determining how latent female preferences either exaggerate the magnitude of current traits （i.e. elaborations） or favor novel traits （i.e. innovations）. In tt^ngara frogs, females prefer complex mating calls （whine-chucks） to simple calls （whine only）. The whine is critical for mate recognition while the chuck further enhances the attractiveness of the call. Here we use a combina- tion of synthetic and natural stimuli to examine latent female preferences. Our results show that a diversity of stimuli, including conspecific and heterospecific calls as well as predator-produced and human-made sounds, increase the attractiveness of a call when added to a whine. These stimuli do not make simple calls more attractive than a whine-chuck, however. In rare cases we found stimuli that added to the whine decrease the attractiveness of the call. Overall, females show strong preferences for both elaborations and innovations of the chuck. We argue that the emancipation of these acoustic adornments from mate recognition allows such female permissiveness, and that male constraints on signal evolution are probably more important in explaining why males evolved their specific adornment. Experimentally probing latent female preferences for stimuli out of the species＇ range is a useful means to gain insights about the potential of female choice to influence signal evolution and thus the astounding diversity in male sexually-selected traits [Current Zoology 56 （3）： 343-357, 2010].

关键词： Mate choice Ornament evolution Tfingara frogs Physalaemus pustulosus

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一种泡蟾的配偶识别:脑、行为和进化研究(英文)

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动物学报 2003年第6期49卷 713-726页

作者： Michael J.RYAN a.stanley rand Section of Integrative Biology C0930 Smithsonian Tropical Research Institute University of TexasAustin Texas 78712USASmithsonian Tropical Research InstituteApartado 2072BalboaPanamaApartado 2072BalboaPanama

综述了对泡蟾 (Physalaemuspustulosus)的性通讯所进行的各种研究。本文作者研究了通讯系统的功能重要性、通讯的神经机制以及通讯进化的格局 ,特别研究了雌蛙如何使用简单和复杂的叫声来识别可以交配的物种 ,以及如何识别同种的不同雄... 详细信息

综述了对泡蟾 (Physalaemuspustulosus)的性通讯所进行的各种研究。本文作者研究了通讯系统的功能重要性、通讯的神经机制以及通讯进化的格局 ,特别研究了雌蛙如何使用简单和复杂的叫声来识别可以交配的物种 ,以及如何识别同种的不同雄性个体。本文确定了复杂叫声的反选择力、一种食蛙蝠———缨唇蝠 (Trachopscirrhosus)以及叫声的能量消耗 ,并阐述了引起雌性反应的重要特征。作者的比较研究表明 ,对复杂叫声的偏好在复杂叫声进化前就有了 ,这支持感官开发假说 (Hypothesisofsensoryexploitation ,雄性特征进化的结果是开发雌性预先存在的对雄性的偏好 )。结合比较研究和人工神经网络的模拟。

关键词：动物通讯泡蟾性选择配偶识别脑行为进化

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A robust behavior of Feed Forward Back propagation algorithm of Artificial Neural Networks in the application of vertical electrical sounding data inversion

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Geoscience Frontiers 2012年第5期3卷 729-736页

作者： Y.Srinivas a.stanley Raj D.Hudson Oliver D.Muthuraj N.Chandrasekar Centre for Geotechnology Manonmaniam Sundaranar UniversityTirunelveliTamil Nadu-627012India M.D.T.Hindu college TirunelveliTamil NaduIndia

The applications of intelligent techniques have increased exponentially in recent days to study most of the non-linear parameters. In particular, the behavior of earth resembles the non- linearity applications. An efficient tool is needed for the interpretation of geophysical parameters to study the subsurface of the earth. Artificial Neural Networks （ANN） perform certain tasks if the structure of the network is modified accordingly for the purpose it has been used. The three most robust networks were taken and comparatively analyzed for their performance to choose the appropriate network. The single- layer feed-forward neural network with the back propagation algorithm is chosen as one of the well- suited networks after comparing the results. Initially, certain synthetic data sets of all three-layer curves have been taken tk^r training the network, and the network is validated by the field datasets collected from Tuticorin Coastal Region （78°7＇30＂E and 8°48＇45＂N）, Tamil Nadu, India. The interpretation has been done successfully using the corresponding learning algorithm in the present study. With proper training of back propagation networks, it tends to give the resistivity and thickness of the subsurface layer model of the field resistivity data concerning the synthetic data trained earlier in the appropriate network. The network is trained with more Vertical Electrical Sounding （VES） data, and this trained network is demon- strated by the field data. Groundwater table depth also has been modeled.

关键词： Artificial neural networks(ANN) Resistivity inversion coastal aquifer parameters Layer model

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Prevalence and Determinants of Obesity Among Healthcare Workers in a Nigerian Tertiary Hospital: A Cross-Sectional Study

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Open Journal of Pathology 2025年第1期15卷 1-15页

作者： Felix Edoiseh Ehidiamhen Ikenna Chijindu Nwigwe Ndidiamaka Anastasia Inyima Andrew Isimenmen Okoawoh Wisdom Chizubem Isaac Olushola Olakunle Jegede stanley Emeka Ogbata Bruno Basil Department of Pathology Faculty of Basic Clinical Sciences David Umahi Federal University of Health Sciences Uburu Ebonyi State Nigeria International Institute for Pathology and Forensic Science Research David Umahi Federal University of Health Sciences Uburu Ebonyi State Nigeria Department of Nutrition and Dietetics David Umahi Federal University Teaching Hospital Uburu Ebonyi State Nigeria Department of Clinical Services and Training David Umahi Federal University Teaching Hospital Uburu Ebonyi State Nigeria Emergency Department St Peters Hospital (Ashford and St Peters NHS Foundation) Chertsey Surrey UK Department of Anatomic Pathology Federal Medical Centre Umuahia Abia State Nigeria

Background: Obesity is a chronic complex disease defined by excessive fat deposits that can impair health. Obesity occurs as a result of an imbalance in diet (energy intake) and physical activity (energy expended), multifactorial diseases due to obesogenic environment (availability of convenience food, media influence, etc.), psycho-social factors (social support systems, cultural/environmental influence, etc.) and genetic variants. Other causes are a subgroup of etiological factors (medications, diseases, immobilization, iatrogenic procedures, monogenic disease/genetic syndrome). Obesity is measured clinically by several common tools apart from body mass index (BMI), such as waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio, and neck circumference. WC and WHR are common tools for measuring central obesity while BMI measures generalized obesity. Aims: The goal of this study is to assess the prevalence of obesity amongst health workers of David Umahi Federal University Teaching Hospital, Uburu, Ebonyi state, Southeast Nigeria and to note the prevailing factors. A reliable estimate of the prevalence of obesity among health workers will contribute to the statistics needed to sway policymakers in the country to take urgent and substantial action on the increasing prevalence of obesity, especially in the healthcare industry. Methodology: The study was carried out between May 2024 and June 2024 at the David Umahi Federal University Teaching Hospital situated in Uburu, Ohaozara Local government area of Ebonyi state, Southeast Nigeria. The questionnaire was designed using the Finnish diabetic risk score (FINDRISC). It contained basic comprehending questions on age, gender, exposure to high blood pressure medication, and anthropometric measurement amongst others. Weight was taken with a portable weighing scale and height, with a stadiometer. Both were taken with shoes and headgear removed. The BMI was calculated using the weight (kg) divided by the sq

关键词： Obesity Healthcare Workers Hospital Ebonyi Nigeria

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2025年美股展望:27％的涨幅能否延续?

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证券市场周刊 2025年第1期 22-24页

作者：詹姆斯·斯坦利嘉盛集团

这是股市辉煌之年.上一次标普500指数涨幅如此之大时,还是在1999年,当时该指数一直强劲上扬.标普500指数在2024年又上涨了27％(截至撰写本文时,距离年底还有两周多一点的时间).这使得该指数的两年涨幅达到了惊人的57％.这将是该指数自1...

这是股市辉煌之年.上一次标普500指数涨幅如此之大时,还是在1999年,当时该指数一直强劲上扬.标普500指数在2024年又上涨了27％(截至撰写本文时,距离年底还有两周多一点的时间).这使得该指数的两年涨幅达到了惊人的57％.这将是该指数自1997年和1998年以来最大的两年涨幅,当时标普500指数在这两年期间上涨了68.49％,并一直持续到1999年,最终在2000年因科技泡沫破裂而回落.

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Circularly and elliptically polarized light under water and the Umov effect

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Light(Science & Applications) 2019年第1期8卷 901-906页

作者： Yitian Ding stanley Pau College of Optical Sciences University of ArizonaTucsonAZ 85721USA

Total internal reflection occurs when light is incident on the interface of high-and low-refractive-index materials at an angle greater than the critical *** with high degree of linear polarization,such as atmospheric scattered skylight,can be converted with a high efficiency up to 53%to circular and elliptical polarizations by total internal reflection under water in the region outside Snell’s *** degree of circular polarization is observed to be inversely dependent on the albedo of underwater objects and is shown to be a direct consequence of the Umov *** results are important for underwater polarimetry,surveillance applications and studies of marine animals’polarized vision near the water-air interface.

关键词： effect. polarized underwater

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PHASE EQUILIBRIUM OF COMPLEX MIXTURES WITH EQUATIONS OF STATE: AN UPDATE5

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Chinese Journal of Chemical Engineering 1995年第1期3卷 42-53页

作者： stanley I.Sandler Hasan orbey Center for Molecular and Engineering Thermodynamics Department of Chemical EngineeringUniversity of DelawareNewarkDE 19716 USACenter for Molecular and Engineering ThermodynamicsDepartment of Chemical EngineeringUniversity of DelawareNewarkDE 19716 USA

Here we review a new class of mixing rules (hat have extended range of mixtures and conditions that can now be described by equation of state models. One characteristic of these mixing rules is that they simultaneously satisfy the boundary conditions of producing a second virial coefficient that is quadratic in mole fraction, and a free energy of mixing like that of an activity coefficient model at high density, though the mixing rule is itself independent of density. We show that using this mixing rule, various asymmetric, highly nonideal mixtures can be accurately described. One serendipitous result is that the parameters in this mixing rule model are almost independent of temperature, which allows accurate extrapolations of phase behavior to be made over large ranges of temperature and pressure.

关键词： equations of state mixing rules phase equilibrium complex mixtures

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A Start Point for Extracellular Nucleotide Signaling

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Molecular Plant 2014年第6期7卷 937-938页

作者： stanley J. Roux Department of Molecular Biosciences University of Texas at Austin Austin TX 78712 USA

A START POINT FOR EXTRACELLULAR NUCLEOTIDE SIGNALINGThe recent discovery of a plant receptor for extracellu- lar nucleotides, reported by Choi et al. （2014）, is a major breakthrough that had been anticipated for over a dec- ade. Plants release ATP into their extracellular matrix （ECM） during growth and when they are induced by vari- ous biotic and abiotic stimuli （Clark and Roux, 2011）. That these extracellular nucleotides would activate receptors in plants was predicted by two sets of discoveries： that low- and sub-micromolar ATP could induce increases in [Ca2＋]cyt, NO, and superoxide signaling intermediates that led to downstream growth, stomatal, and defense responses, and that these changes could be blocked by antagonists that blocked extracellular nucleotide receptors in animals （Demidchik et al., 2003; Song et al., 2006; Clark et al., 2011; Demidchik et al., 2009, 2011）. Although mammalian biolo- gists had discovered two classes of receptors for extracel- lular nucleotides （P2X and P2Y） decades ago （Burnstock, 2007）, there were no plant proteins obviously similar to these in any sequence data available. Clearly, if there were plant purinoceptors, they would be different from the mammalian receptors, and they could not be discovered by motif searches.

关键词： @@

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Spontaneous Recovery in Directed Dynamical Networks

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Engineering 2024年第6期37卷 208-214页

作者： Xueming Liu Xian Yan H.Eugene stanley School of Artificial Intelligence and Automation&The MOE Engineering Research Center of Autonomous Intelligent Unmanned Systems&the Key Laboratory of Image Processing Huazhong University of Science and TechnologyWuhan 430074China Center for Polymer Studies Department of PhysicsBoston UniversityBostonMA 02215USA

Complex networked systems,which range from biological systems in the natural world to infrastructure systems in the human-made world,can exhibit spontaneous recovery after a failure;for example,a brain may spontaneously return to normal after a seizure,and traffic flow can become smooth again after a *** studies on the spontaneous recovery of dynamical networks have been limited to undirected ***,most real-world networks are *** fill this gap,we build a model in which nodes may alternately fail and recover,and we develop a theoretical tool to analyze the recovery properties of directed dynamical *** find that the tool can accurately predict the final fraction of active nodes,and the prediction accuracy decreases as the fraction of bidirectional links in the network increases,which emphasizes the importance of directionality in network *** to different initial states,directed dynamical networks may show alternative stable states under the same control parameter,exhibiting hysteresis *** addition,for networks with finite sizes,the fraction of active nodes may jump back and forth between high and low states,mimicking repetitive failure-recovery *** findings could help clarify the system recovery mechanism and enable better design of networked systems with high resilience.

关键词： Network resilience Directed dynamical networks Spontaneous recovery

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An Example Using Improved Lefschetz Duality

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Chinese Annals of Mathematics,Series B 2017年第6期38卷 1269-1274页

作者： Pascal LAMBRECHTS Jeremy LANE Donald stanley Pascal Lambrechts Institut Mathmatique Universit de Louvain Department of Mathemtics University of Toronto Department of Mathematics and Statistics University of Regina

A theorem of Lambrechts and stanley is used to find the rational cohomology of the complement of an embedding S^(4n-1)→ S^(2n)× S^m as a module and demonstrate that it is not necessarily determined by the map induced on cohomology by the embedding, nor is it a trivial extension. This demonstrates that the theorem is an improvement on the classical Lefschetz duality.

关键词： Lefschetz duality Embedding Extension problem

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