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competition for food in 2 populations of a wild-caught fish

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current Zoology 2018年第5期64卷 615-622页

作者： Pierre J.c. cHUARD Grant E. BROWN james W.A. GRANT Research School of Biology The Australian National University Canberra ACT 0200 Australia Departmentof Biology Concordia University 7141 Sherbrooke Street West Montreal Quebec Canada H4B 1R6

Aggressive behavior when competing for resources is expected to increase as the ratio of competitors-to-resource ratio （cRR） units increases. Females are expected to be more aggressive than males when competing for food when body size is more strongly related to reproductive suc- cess in females than in males, whereas aggression is predicted to decrease under high ambient predation risk by natural selection. Under the risk allocation model, however, individuals under high ambient predation risk are expected to be more aggressive, and forage more in the absence of imminent risk than their low risk counterparts. An interaction between adult sex ratio （i.e., adult males/females）, ambient predation risk （high vs. low）, and sex on intrasexual competition for mates in Trinidadian guppies Poecilia reticulata has been shown. The interaction suggested an increase in aggression rates as cRR increased, except for males from the high predation population. To compare the patterns of competition for food versus mates, we replicated this study by using food patches. We allowed 4 male or 4 female guppies from high and low predation populations to com- pete for 5, 3, or 1 food patches. The foraging rate was higher in a high rather than low ambient pre- dation risk population. Surprisingly, cRR, sex, and population of origin had no effect on aggression rates. Despite other environmental differences between the 2 populations, the effect of ambient predation risk may be a likely explanation for differences in foraging rates. These results highlight the importance for individuals to secure food despite the cost of competition and predation.

关键词： aggression competitor-to-resource ratio foraging Poecifia reticulata population differences predation risk sex

infrastructure-based localisation of automated coal mining equipment

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international Journal of coal Science & Technology 2017年第3期4卷 252-261页

作者： chad O. Hargrave craig A. james Jonathon c. Ralston Mining and Processing Technologies Research Group CoalMining Research Program CSIRO Energy BrisbaneAustralia

A novel radar-based system for longwall coal mine machine localisation is described. The system, based on a radar-ranging sensor and designed to localise mining equipment with respect to the mine tunnel gate road infrastructure, is developed and trialled in an underground coal mine. The challenges of reliable sensing in the mine environment are considered, and the use of a radar sensor for localisation is justified. The difficulties of achieving reliable positioning using only the radar sensor are examined. Several probabilistic data processing techniques are explored in order to estimate two key localisation parameters from a single radar signal, namely along-track position and across-track position, with respect to the gate road structures. For the case of across-track position, a conventional Kalman filter approach is sufficient to achieve a reliable estimate. However for along-track position estimation, specific infrastructure elements on the gate road rib-wall must be identified by a tracking algorithm. Due to complexities associated with this data processing problem, a novel visual analytics approach was explored in a 3D interactive display to facilitate identification of significant features for use in a classifier algorithm. Based on the classifier output, identified elements are used as location waypoints to provide a robust and accurate mining equipment localisation estimate.

关键词： Localisation · Waypoint navigation · Machine learning · Radar ·Underground · Longwall mining· Automation

Scaling Symmetry and integrable Spherical Hydrostatics

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Journal of Modern Physics 2013年第4期4卷 486-494页

作者： Sidney Bludman Dallas c. kennedy Departamento de Astronomía Universidad de Chile Santiago Chile Natick USA

Any symmetry reduces a second-order differential equation to a first integral: variational symmetries of the action (exemplified by central field dynamics) lead to conservation laws, but symmetries of only the equations of motion (exemplified by scale-invariant hydrostatics) yield first-order non-conservation laws between invariants. We obtain these non- conservation laws by extending Noether’s Theorem to non-variational symmetries and present an innovative variational formulation of spherical adiabatic hydrostatics. For the scale-invariant case, this novel synthesis of group theory, hydrostatics, and astrophysics allows us to recover all the known properties of polytropes and define a core radius, inside which polytropes of index n share a common core mass density structure, and outside of which their envelopes differ. The Emden solutions (regular solutions of the Lane-Emden equation) are obtained, along with useful approximations. An appendix discusses the n = 3 polytrope in order to emphasize how the same mechanical structure allows different thermal structures in relativistic degenerate white dwarfs and zero age main sequence stars.

关键词： Lagrangian Mechanics Symmetry Hydrodynamics Astrophysics Stellar Structure

Migmatite-like textures in anthracite:Further evidence for low-grade metamorphic melting and resolidification in high-rank coals

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Geoscience Frontiers 2021年第3期12卷 428-436页

作者： james c.Hower Susan M.Rimmer Maria Mastalerz Nicola J.Wagner University of Kentucky center for Applied Energy Research 2540 Research Park DriveLexingtonKY 40511USA School of Earth Systems and Sustainability Southern Illinois University CarbondaleCarbondaleIL 62901USA indiana Geological&Water Survey Indiana UniversityBloomingtonIN 47405USA Department of Geology University of JohannesburgJohannesburgSouth Africa

Previous studies demonstrated that melting,initiated by supercritical fluids in the 375-400℃range,occurred as part of anthracite metamorphism in the Appalachian *** on the known behavior of vitrinite at high temperatures and,to a lesser extent,at high pressures,it was determined that the duration of the heating,melting,and resolidification event was about 1 *** the current study,featureless vitrinite within banded maceral assemblages demonstratesthe intimate association of melted and resolidified vitrinite with anthracite-rank *** analogy with metamorphosed inorganic rocks,such associations represent diadysites and embrechites,i.e.,cross-cutting and layered migmatites,*** though the temperature of formation of the anthracite structures is several hundred℃lower than that seen in metamorphosed inorganic rocks,anthracites are metamorphic rocks and the nomenclature for metamorphic rocks may be appropriate for coal.

关键词： igneous Metamorphic texture Pennsylvania Mesozoic basins South Africa

A simple,azulene-based colorimetric probe for the detection of nitrite in water

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Frontiers of chemical Science and Engineering 2020年第1期14卷 90-96,F0004页

作者： Lloyd c.Murfin carlos M.Lopez-Alled Adam c.Sedgwick Jannis Wenk Tony D.james Simon E.Lewis Department of chemistry University of BathBath BA27AYUK centre for Sustainable chemical Technologies University of BathBath BA27AYUK Department of chemical Engineering and Water innovation and Research centre(WiRc@Bath) University of BathBath BA27AYUK

We describe the synthesis and evaluation of an azulene-based chemodosimeter for *** probe was found to undergo two distinct color changes upon introduction of aqueous nitrite ion.A near-instant formation of a grey color provides a qualitative indication of the presence of nitrite,followed by the formation of a deep-yellow/orange color,the endpoint from which quantitative data can be *** azulene probe exhibits 1:1 stoichiometry of reaction with nitrite in water,and is selective for nitrite over other *** azulene probe was applied to determine nitrite content in cured meat,and compared with the British Standard testing procedure(Griess test).The value obtained from the azulene-based probe agreed closely with the standard *** procedure only requires the preparation of one standard solution,instead of the three required for the standard Griess test.

关键词： azulene nitrite diazoquinone

Methods for latent image simulations in photolithography with a polychromatic light attenuation equation for fabricating ViAs in 2.5D and 3D advaneed packaging architectures

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Microsystems & Nanoengineering 2021年第3期7卷 85-96页

作者： Daniel c.Smallwood Paul Mccloskey cian OzMathuna Declan P.casey james F.Rohan MicroNano Systems centre Tyndall National InstituteUniversity College CorkLee MaltingsCork T12 R5CPIreland School of Engineering University College CorkCollege RoadCorkIreland

As demand accelerates for multifunctional devices with a small footprint and minimal power consumption,2.5D and 3D advanced packaging architectures have emerged as an essential solution that use through-substrate vias(TSVs)as vertical in *** stacking en ables chip packages with increased functi on ality,enhanced desig n versatility,minimal power loss,reduced footprint and high *** the potential of photolithography for vertical interconnect access(ViA)fabrication requires fast and accurate predictive modeling of diffraction effects and resist film *** procedure is especially challenging for broad-spectrum exposure systems that use,for example,Hg bulbs with g-,h-,and i-line UV *** this paper,we present new methods and equations for ViA latent image determination in photolithography that are suitable for broad-spectrum exposure and negate the need for complex and time-consuming in situ *** technique is accurate,converges quickly on the average modern Pc and could be readily integrated into photolithography simulation *** derive a polychromatic light attenuation equation from the Beer-Lambert law,which can be used in a critical exposure dose model to determine the photochemical reaction *** in teg rate this equation with an exact scalar diffraction formula to produce a succinct equation comprising a complete coupling between light propagation phenomena and photochemical *** then perform a comparative study between 2D/3D photoresist latent image simulation geometries and directly corresponding experimental data,which demonstrates a highly positive *** anticipate that this technique will be a valuable asset to photolithography,micro-and nano-optical systems and advaneed packaging/system integration with applications in technology domains ranging from space to automotive to the internet of Things(loT).

关键词： latent image equation

Nanomineralogy of evaporative precipitation of efflorescent compounds from coal mine drainage

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Geoscience Frontiers 2021年第6期12卷 404-410页

作者： Luis F.O.Silva Diana Pinto Guilherme L.Dotto james c.Hower Department of civil and Environmental.Universidad de La costa CUCCalle 58#55–66BarranquillaAtlanticoColombia Universidade Federal de Santa Maria–UFSM 1000Roraima Avenue97105–900Santa MariaRSBrazil University of Kentucky Department of Earth&Environmental SciencesLexingtonKY40506USA University of Kentucky Center for Applied Energy Research2540 Research Park DriveLexingtonKY40511USA

Efflorescent nanophases(NPs) are found as a transitory accumulation of potentially hazardous elements(PHEs),particularly in tropical climates. The central objective of this study was to investigate the distribution of PHEs with NPs through the evaporative formation structures(EFS) of enormously PHEs-rich coal-mine drainages(cMD). The EFS were studied in natural coal mine drainage for five months in order to determine their geochemical and ecological structures and to assess their position in the reduction of PHEs in nature. The largest coal-fired power plant in South America, located in south Brazil, is used as an example of such a problem. in this work, a novel methodology for the analysis of PHEs in cMD precipitates is proposed for this affected coal *** analytical method, combining X-Ray Diffraction(XRD) and advanced electron microscopies, shows the importance of nanomineralogy in understanding different circumstances of coal contamination. Several ultrafinenanoparticles(UNPs) were identified in the sampled soils and river sediments together with the PHEs. A decrease in PHEs was identified in association with UNPs. However, further investigations are required with regard to the mobility of PHEs in water, atmosphere, soils, and sediments. The EPS was thoroughly studied, acquiring suitable understanding with investigational facts for ca and Fe-sulphates, pickeringite, and several amorphous phases.

关键词： coal mine drainage Evaporative precipitation Sediments Water and soil pollution

Selective androgen receptor modulators for the treatment of late onset male hypogonadism

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Asian Journal of Andrology 2014年第2期16卷 256-261,I0009页

作者： christopher c coss Amanda Jones Michael L Hancock Mitchell S Steiner james T Dalton GTx Inc. Memphis Tennessee USA.

Several testosterone preparations are used in the treatment of hypogonadism in the ageing male. These therapies differ in their convenience, flexibility, regional availability and expense but share their pharmacokinetic basis of approval and dearth of long-term safety data. The brevity and relatively reduced cost of pharmacokinetic based registration trials provides little commercial incentive to develop improved novel therapies for the treatment of late onset male hypogonadism. Selective androgen receptor modulators （SARMs） have been shown to provide anabolic benefit in the absence of androgenic effects on prostate, hair and skin. current clinical development for SARMs is focused on acute muscle wasting conditions with defined clinical endpoints of physical function and lean body mass. Similar regulatory clarity concerning clinical deficits in men with hypogonadism is required before the beneficial pharmacology and desirable pharmacokinetics of SARMs can be employed in the treatment of late onset male hypogonadism.

关键词： hypogonadism late onset hypogonadism selective androgen receptor modulators testosterone

Semantic Segmentation of Sorghum Using Hyperspectral Data identifies Genetic Associations

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Plant Phenomics 2020年第1期2卷 14-24页

作者： chenyong Miao Alejandro Pages Zheng Xu Eric Rodene Jinliang Yang james c.Schnable center for Plant Science innovation University of Nebraska-LincolnLincolnNEUSA Department of Agronomy and Horticulture University of Nebraska-LincolnLincolnNEUSA Quantitative Life Sciences initiative University of Nebraska-LincolnLincolnNEUSA Department of Mathematics and Statistics Wright State UniversityDaytonOHUSA

This study describes the evaluation of a range of approaches to semantic segmentation of hyperspectral images of sorghum plants,classifying each pixel as either nonplant or belonging to one of the three organ types(leaf,stalk,panicle).While many current methods for segmentation focus on separating plant pixels from background,organ-specific segmentation makes it feasible to measure a wider range of plant *** scored training data for a set of hyperspectral images collected from a sorghum association population was used to train and evaluate a set of supervised classification *** algorithms show acceptable accuracy for this classification *** trained on sorghum data are able to accurately classify maize leaves and stalks,but fail to accurately classify maize reproductive organs which are not directly equivalent to sorghum *** measurements extracted from semantic segmentation of sorghum organs can be used to identify both genes known to be controlling variation in a previously measured phenotypes(e.g.,panicle size and plant height)as well as identify signals for genes controlling traits not previously quantified in this population(e.g.,stalk/leaf ratio).Organ level semantic segmentation provides opportunities to identify genes controlling variation in a wide range of morphological phenotypes in sorghum,maize,and other related grain crops.

关键词： Sorghum classify organs