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Asymmetric reinforcement in Lucania killifish:assessing reproductive isolation when both sexes choose

Current Zoology 2021年第2期67卷 215-224页

作者： Michelle e.ST.john Rebecca C.FULLeR School of Integrative Biology University of liois Urbana-ChampaignChampaignIL 61820USA

Reinforcement can occur when maladaptive hybridization in sympatry favors the evolution of con-specific preferences and target traits that promote behav ioral isolation(BI).In many systems,enhanced BI is due to increased female preference for *** others,BI is driven by male preference,and in other systems both sexes exert *** of these patterns can be atributed to classic sex-specific costs and benefits of ***,sex differences in conspecific preference can emerge due to asymmetric postzygotic isolation(e.g.,hybrid offspring from female A × male B have lower fitness than hybrid offspring from female B × male A),which can lead to asymmetric BI(e.g.,female A and male B are less likely to mate than female B and male A).Understanding reinforcement requires understanding how conspecific preferences evolve in ***,estimating conspecific preferences can be difficult when both sexes are *** this study,we use Lucania killifish to test the hypothesis that patterns of reinforcement are driven by asymmetric postzygotic isolation between *** true,we predicted that sympatric female Lucania goodei and sympatric male *** should have lower levels of BI compared with their sympatric counterparts,as they produce hybrid offspring with the highest *** address the problem of measuring BI when both sexes are choosy,we inferred the contribution to BI of each partner using assays where one sex in the mating pair comes from an allopatric population with potentially low preference,whereas the other comes from a sympatric population with high *** one hybrid cross direction,we found that both female *** and male *** have high contributions to BI in *** the other hybrid cross direction,we found that only female *** contribute to *** male *** readily engaged in hybrid spawnings with allo-patric *** *** results indicate that both asymmetric postzygotic isolation

关键词： reinforcement behavioral isolatin female mate choice male mate choice asymmetric costs to hybridization

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environment as the Stage for economic Actors

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Chinese Journal of Population,Resources and environment 2007年第1期5卷 3-8页

作者： john e Coulter Shi Lei Samantha Jenkins Suite 605 Silver Tower No. 2 Dong San Huan Bei Road Chaoyang Beijing 100027 China SePA Key Laboratory on eco-industry Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China Department of Technology Mathematics and CS University West Trollhatten SE 461 29 Sweden

The relative importance of economics and environment in debate may soon be reversed due to the influence of three fac- tors. Firstly, in the global economy it is hard to hide the unwanted products of economic processes. Secondly, huge advances in sci- ence will reduce the imperfect knowledge of markets, making some monitoring and analyzing tools show the design of sensible and equitable livelihood in communities, which is more important than the motivation of maximising profits for some individuals or firms. Thirdly, China, as the last major player on the planet to take on economic growth, comes from traditions fundamentally differ- ent from those economies that have experienced the Industrial Revolution previously. Its challenges with sustainability and en- vironmental conservation predate Western economics by millennia, and it is implementing policies domestically and starting to work on the world stage that acknowledges that the surroundings are the host for any economic and socio-political system.

关键词： economics market entropy China

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Development of Shallow Footing Anti-Ram Bollard System Through Modeling and Testing

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Transactions of Tianjin University 2006年第B9期12卷 46-50页

作者： CRAWFORD john e Karogozian & Case 2550 N.Hollywood WaySuite 500BurbankCA 91505USA

In past terrorist attacks, vehicle borne improvised explosive devices (VBIeD) have been the primary manner of attacking buildings and infrastructures. Preventing unauthorized vehicles from approaching a protected area with anti-ram systems would maintain an established standoff distance against moving and stationary vehicles and consequently reduce blast and debris threats. This strategy has been considered the first line of defence against terrorists. Several types of anti-ram devices have been developed in accordance with U. S. Department of State K-rating criteria, for example, wedge barriers, rising beams, sliding/swing gates, and drop arms. However, these devices typically need a deep foundation for installation and can't be implemented into many locations where a depth of excavation is limited in order to protect utility lines of buildings and infrastructures. This paper presents a recent development of a series of shallow footing anti-ram bollard systems (SFABS) that can satisfy K-12 rating with only five-inch thick footing. A high-fidelity physics based finite element technique with a vehicle crash model is used for predicting anti-ram capacity and determining design parameters of the SFABS. Full-scale vehicle crash tests of the developed SFABS systems have been carried out to validate the design and analysis.

关键词： anti-ram bollard shallow footing crash testing finite element analysis

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Rare case of tibial hemimelia,preaxial polydactyly,and club foot

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World Journal of Clinical Cases 2016年第12期4卷 401-408页

作者： Guinevere Granite john e Herzenberg Ronald Wade Department of Anatomy and Neurobiology School of MedicineUniversity of Maryland Rubin Institute for Advanced Orthopedics Sinai Hospital of Baltimore Department of Anatomical Services University of Maryland

A seven-month old female presented with left tibial hemimelia(or congenital tibial aplasia; Weber type VIIb, Jones et al type 1a), seven-toed preaxial polydactyly, and severe club foot(congenital talipes equinovarus). Definitive amputation surgery disarticulated the lower limb at the knee. This case report describes the anatomical findings of a systematic post-amputation examination of the lower limb's superficial dissection, X-ray s, and computed to mography (CT) scans. From the X-rays and CT scans, we found curved and overlapping preaxial supernumerary toes, hypoplastic first metatarsal, lack of middle and distal phalanges in one supernumerary toe, three tarsal bones, hypoplastic middle phalanx and no distal phalanx for fourth toe, andno middle or distal phalanges for fifth toe. The fibula articulated with the anteromedial calcaneus and the tibia was completely absent. We identified numerous muscles and nerves in the superficial dissection that are described in the results section of the case report. Due to the rarity of this combination of anatomical findings, descriptions of such cases are very infrequent in the literature.

关键词： Club foot Congenital talipes equinovarus Preaxial polydactyly Tibial hemimelia Congenital tibial aplasia

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A unified intrinsic functional expansion theory for solitary waves

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Acta Mechanica Sinica 2005年第1期21卷 1-15页

作者： Theodore Yaotsu Wu john Kao Jin e.Zhang California Institute of Technology Pasadena.CA 91125U.S.A.FellowInstitute of MechanicsChinese Academy of SciencesBeijing 100080China Warner Brothers GlendaleCA 91203.U.S.A. The university of Hong Kong.Pokfulam Road.Hong Kong SAR.China

A new theory is developed here for evaluating solitary waves on water, with results of high accuracy uniformly valid for waves of all heights, from the highest wave with a corner crest of 120 down to very low ones of diminishing height. Solutions are sought for the euler model by employing a unified expansion of the logarithmic hodograph in terms of a set of intrinsic component functions analytically determined to represent all the intrinsic properties of the wave entity from the wave crest to its outskirts. The unknown coefficients in the expansion are determined by minimization of the mean-square error of the solution, with the minimization optimized so as to take as few terms as needed to attain results as high in accuracy as attainable. In this regard, Stokess formula, F2= tan , relating the wave speed (the Froude number F) and the logarithmic decrement of its wave field in the outskirt, is generalized to establish a new criterion requiring (for minimizing solution error) the functional expansion to contain a finite power series in M terms of Stokess basic term (singular in ), such that 2M is just somewhat beyond unity, i.e. 2M1. This fundamental criterion is fully validated by solutions for waves of various amplitude-to-water depth ratio =a/h, especially about 0.01, at which M=10 by the criterion. In this pursuit, the class of dwarf solitary waves, defined for waves with 0.01, is discovered as a group of problems more challenging than even the highest wave. For the highest wave, a new solution is determined here to give the maximum height hst=0.8331990, and speed Fhst=1.290890, accurate to the last significant figure, which seems to be a new record.

关键词： Solitary waves on water Unified intrinsic functional expansion theory exact solutions High-accuracy computation of waves of arbitrary height Mass and energy transfer

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Genetic variability of the stable fly assessed on a global scale using amplified fragment length polymorphism

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Insect Science 2016年第5期23卷 695-703页

作者： Kathleen M Kneeland Steven R. Skoda john e. Foster Department of entomology 103 Entomology Haft University of Nebraska-Lincoln Lincoln NE 68583 USDA-ARS-KBUSLIRL Screwworm Research Unit 2700 Fredericksburg Road Kern/ille TX 78028 USA

The stable fly, Stomoxys calcitrans （L.）（Diptera： Muscidae）, is a blood-feeding, economically important pest of animals and humans worldwide. Improved management strategies are essential and their development would benefit from studies on genetic di- versity of stable flies. especially if done on a global scale, such research could generate information necessary for the development and application of more efficient control meth- ods. Herein we report on a genetic study of stable flies using amplified fragment length polymorphism, with samples of 10-40 individuals acquired from a total of 25 locations in the Nearctic, Neotropic, Palearctic, Afrotropic and Australasian biogeographical regions. We hypothesized that genetic differentiation would exist across geographical barriers. Although Fsx （0.33） was moderately high, the Gsx （0.05; representing genetic diversity between individuals） was very low; Nm values （representing gene flow） were high （9.36）. The mismatch distribution and tests of neutrality suggested population expansion, with no genetic differentiation between locations. The analysis of molecular variance （AMOVA） results showed the majority of genetic diversity was within groups. The mantel test showed no correlation between geographic and genetic distance; this strongly supports the AMOVA results. These results suggest that stable flies did not show genetic differentiation but are panmictic, with no evidence of isolation by distance or across geographical barriers.

关键词： AFLP biting flies external parasites genetic diversity livestock pests Stomoxys calcitrans

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DeM Fusion using a modified k-means clustering algorithm

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International Journal of Digital earth 2016年第12期9卷 1242-1255页

作者： Colleen e.Fuss Aaron A.Berg john B.Lindsay Department of Geography University of GuelphGuelphCanada

Digital elevation models(DeMs)are a necessary dataset for modelling the earth’s surface;however,all DeMs contain *** can reduce this error using DeM fusion techniques since numerous DeMs can be available for a ***,the use of a clustering algorithm in DeM fusion has not been previously *** this study a new DeM fusion algorithm based on a clustering approach that works on multiple DeMs to exploit consistency in the estimates as indicators of accuracy and precision is *** fusion approach includes slope and elevation thresholding,k-means clustering of the elevation estimates at each cell location,as well as filtering and smoothing of the fusion *** of the input DeMs,and the products of each step of the fusion algorithm,with a higher accuracy reference DeM enabled a detailed analysis of the effectiveness of the DeM fusion *** main findings of the research were:the k-means clustering of the elevations reduced the precision which also impacted the overall accuracy of the estimates;the number of final cluster members and the standard deviation of elevations before clustering both had a strong relationship to the error in the k-means estimates.

关键词： DeM fusion k-means clustering DeM error

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Course evaluation Based on Deep Learning and SSA Hyperparameters Optimization

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Computers, Materials & Continua 2022年第4期71卷 941-959页

作者： Alaa A.el-Demerdash Sherif e.Hussein john FW Zaki Department of Computer and Systems Faculty of EngineeringMansoura UniversityMansoura35516Egypt

Sentiment analysis attracts the attention of egyptian Decisionmakers in the education *** offers a viable method to assess education quality services based on the students’feedback as well as that provides an understanding of their *** machine learning techniques offer automated strategies to process big data derived from social media and other digital channels,this research uses a dataset for tweets’sentiments to assess a few machine learning *** dataset preprocessing to remove symbols,necessary stemming and lemmatization is performed for features *** is followed by several machine learning techniques and a proposed Long Short-Term Memory(LSTM)classifier optimized by the Salp Swarm Algorithm(SSA)and measured the corresponding ***,the validity and accuracy of commonly used classifiers,such as Support Vector Machine,Logistic Regression Classifier,and Naive Bayes classifier,were ***,LSTM based on the SSA classification model was compared with Support Vector Machine(SVM),Logistic Regression(LR),and Naive Bayes(NB).Finally,as LSTM based SSA achieved the highest accuracy,it was applied to predict the sentiments of students’feedback and evaluate their association with the course outcome evaluations for education quality purposes.

关键词： Sentiment analysis course evaluation deep learning Bi-LSTM opinion mining students feedback natural language processing machine learning tweets analysis SSA

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CONVeRGeNCe ANALYSIS OF A LOCALLY ACCeLeRATeD PReCONDITIONeD STeePeST DeSCeNT MeTHOD FOR HeRMITIAN-DeFINITe GeNeRALIZeD eIGeNVALUe PROBLeMS

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Journal of Computational Mathematics 2018年第5期36卷 739-760页

作者： Yunfeng Cai Zhaojun Bai john e. Pask N. Sukumar LMAM & School of Mathematical Sciences Peking University Beijing 100871 China Department of Computer Science and Department of Mathematics University of California Davis CA 95616 USA Physics Division Lawrence Livermore National Laboratory Livermore CA 94550 USA Department of Civil and environmental engineering University of California Davis CA 95616 USA

By extending the classical analysis techniques due to Samokish, Faddeev and Faddee- va, and Longsine and McCormick among others, we prove the convergence of the precon- ditioned steepest descent with implicit deflation （PSD-id） method for solving Hermitian- definite generalized eigenvalue problems. Furthermore, we derive a nonasymptotie estimate of the rate of convergence of the PSD-id method. We show that with a proper choice of the shift, the indefinite shift-and-invert preconditioner is a locally accelerated preconditioner, and is asymptotically optimal which leads to superlinear convergence Numerical examples are presented to verify the theoretical results on the convergence behavior of the PSD- id method for solving ill-conditioned Hermitian-definite generalized eigenvalue problems arising from electronic structure calculations. While rigorous and full-scale convergence proofs of preconditioned block steepest descent methods in practical use still largely eludes us, we believe the theoretical results presented in this paper shed light on an improved understanding of the convergence behavior of these block methods.

关键词： eigenvalue problem Steepest descent method Preconditioning Superlinear convergence.

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Quantifying spatiotemporal variability in occupant exposure to an indoor airborne contaminant with an uncertain source location

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Building Simulation 2023年第6期16卷 889-913页

作者： john e.Castellini Jr Cary A.Faulkner Wangda Zuo Michael D.Sohn Department of Mechanical engineering University of Colorado BoulderUCB 427BoulderCO80309USA Department Architectural engineering The Pennsylvania State UniversityUniversity ParkPA16802USA National Renewable energy National Laboratory GoldenCO80401USA energy Analysis and environmental Impacts Division Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA94720USA

Well-mixed zone models are often employed to compute indoor air quality and occupant *** effective,a potential downside to assuming instantaneous,perfect mixing is underpredicting exposures to high intermittent concentrations within a *** such cases are of concern,more spatially resolved models,like computational-fluid dynamics methods,are used for some or all of the ***,these models have higher computational costs and require more input information.A preferred compromise would be to continue with a multi-zone modeling approach for all rooms,but with a better assessment of the spatial variability within a *** do so,we present a quantitative method for estimating a room’s spatiotemporal variability,based on influential room *** proposed method disaggregates variability into the variability in a room’s average concentration,and the spatial variability within the room relative to that *** enables a detailed assessment of how variability in particular room parameters impacts the uncertain occupant *** demonstrate the utility of this method,we simulate contaminant dispersion for a variety of possible source *** compute breathing-zone exposure during the releasing(source is active)and decaying(source is removed)*** CFD methods,we found after a 30 minutes release the average standard deviation in the spatial distribution of exposure was approximately 28%of the source average exposure,whereas variability in the different average exposures was lower,only 10%of the total *** also find that although uncertainty in the source location leads to variability in the average magnitude of transient exposure,it does not have a particularly large influence on the spatial distribution during the decaying period,or on the average contaminant removal *** systematically characterizing a room’s average concentration,its variability,and the spatial variability within the room important insights can be gain

关键词： uncertainty variability airborne contaminant spatiotemporal variability well-mixed heterogeneity

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