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Mate choice decisions by searchers

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Current Zoology 2013年第2期59卷 184-199页

作者： daniel D. WIEGMANN Lisa M. ANGELONI Steven M. SEUBERT j. GordonWADE Department of Biological Sciences and j. P. Scott Center for Neuroscience Mind and Behavior Bowling Green State University Bowling Green OH 43403 USA Department of Biology Colorado State University Fort Collins CO 80523 USA Department of Mathematics and Statistics Bowling Green State University Bowling Green OH 43403 USA

For more than two decades rudimentary versions of the fixed sample and sequential search strategies have provided the primary theoretical foundation for the study of mate choice decisions by searchers. The theory that surrounds these models has expanded markedly over this time period. In this paper, we review and extend results derived from these models, with a focus on the empirical analysis of searcher behavior. The basic models are impractical for empirical purposes because they rely on the as- sumption that searchers--and, for applied purposes, researchers--assess prospective mates based on their quality, the fitness consequences of mate choice decisions. Here we expound versions of the models that are more empirically useful, reformulated to reflect decisions based on male phenotypic characters. For some organisms, it may be possible to use preference functions to de- rive predictions from the reformulated models and thereby avoid difficulties associated with the measurement of male quality per se. But predictions derived from the two models are difficult to differentiate empirically, regardless of how the models are formu- lated. Here we develop ideas that illustrate how this goal might be accomplished. In addition, we clarify how the variability of male quality should be evaluated and we extend what is known about how this variability influences searcher behavior under each model. More general difficulties associated with the empirical study of mate choice decisions by searchers are also discussed [Current Zoology 59 （2）： 184-199, 2013].

关键词： Dispersive order Fixed sample strategy Mate choice Preference functions Sequential search Stochastic dominance

The current perspective of the PA 1957 gas well pillar study and its implications for longwall gas well pillars

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International journal of Mining Science and Technology 2021年第1期31卷 117-126页

作者： Peter Zhang daniel Su Chris Mark CDC NIOSH Pittsburgh Mining Research DivisionPittsburghPA 15236USA Mine Safety and Health Administration PittsburghPA 15217USA

Many states rely upon the Pennsylvania 1957 Gas Well Pillar Study to evaluate the coal barrier surrounding gas *** study included 77 gas well failure cases that occurred in the Pittsburgh and Freeport coal seams over a 25-year *** the time,coal was mined using the room-and-pillar mining method with full or partial pillar recovery,and square or rectangle pillars surrounding the gas wells were left to protect the *** study provided guidelines for pillar sizes under different overburden depths up to 213 m(700 ft).The 1957 study has also been used to determine gas well pillar sizes in longwall mines since longwall mining began in the 1970 *** original study was developed for room-and-pillar mining and could be applied to gas wells in longwall chain pillars under shallow ***,under deep cover,severe deformations in gas wells have occurred in longwall chain ***,with a better understanding of coal pillar mechanics,new insight into subsidence movements induced by retreat mining,and advances in numerical modeling,it has become both critically important and feasible to evaluate the adequacy of the 1957 study for longwall gas well *** this paper,the data from the 1957 study is analyzed from a new perspective by considering various factors,including overburden depth,failure location,failure time,pillar safety factor(SF),and floor *** pillar SF and floor pressure are calculated by considering abutment pressure induced by full pillar recovery.A statistical analysis is performed to find correlations between various factors and helps identify the most significant factors for the stability of gas wells influenced by retreat *** analyzing the data from the 1957 study,the guidelines for gas well pillars in the 1957 study are evaluated for their adequacy for roomand-pillar mining and their applicability to longwall *** modeling is used to model the stability of gas wells by quantifying the mining-induced s

关键词： Gas well pillar Pennsylvania 1957 gas well pillar study Room-and-pillar mining Longwall mining

Real-world treatment attrition rates in advanced esophagogastric cancer

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World journal of Gastroenterology 2020年第39期26卷 6027-6036页

作者： Erica S Tsang Howard j Lim daniel j Renouf janine M Davies jonathan M Loree Sharlene Gill Department of Medicine BC CancerVancouver V5Z 4E6Canada Division of Medical Oncology University of British ColumbiaVancouver V5Z 4E6Canada

BACKGROUND Over the last decade,multiple agents have demonstrated efficacy for advanced esophagogastric cancer(EGC).Despite the availability of later lines of therapy,there remains limited real-world data about the treatment attrition rates between lines of *** To characterize the use and attrition rates between lines of therapy for patients with advanced *** We identified patients who received at least one cycle of chemotherapy for advanced EGC between july 1,2017 and july 31,2018 across six regional centers in British Columbia(BC),***,treatment,and outcomes data were *** Of 245 patients who received at least one line of therapy,median age was 66 years(IQR 58.2-72.3)and 186(76%)were male,Eastern Cooperative Oncology Group(ECOG)performance status 0/1(80%),gastric vs GEj(36%vs 64%).Histologies included adenocarcinoma(78%),squamous cell carcinoma(8%),and signet ring(14%),with 31%HER2 positive.72%presented with de novo disease,and 25%had received previous *** was a high level of treatment attrition,with patients receiving only one line of therapy n=122,50%),two lines n=83,34%),three lines n=34,14%),and four lines n=6,2%).Kaplan-Meier analysis demonstrated improved survival with increasing lines of therapy(median overall survival 7.7 vs 16.6 vs 22.8 vs 40.4 mo,P<0.05).On multivariable Cox regression,improved survival was associated with better baseline ECOG and increased lines of therapy(P<0.05).CONCLUSION The steep attrition rates between therapies highlight the unmet need for more efficacious early-line treatment options for patients with advanced EGC.

关键词： Esophagogastric cancer Gastric cancer Treatment attrition Systemic therapy Treatment outcomes Real-world evidence

A meta-analysis of global crop water productivity of three leading world crops(wheat,corn,and rice)in the irrigated areas over three decades

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International journal of Digital Earth 2020年第8期13卷 939-975页

作者： daniel j.Foley Prasad S.Thenkabail Itiya P.Aneece Pardhasaradhi G.Teluguntla Adam j.Oliphant Western Geographic Science Center United States Geological SurveyFlagstaffAZUSA Bay Area Environmental Research Institute(BAERI) NASA Research ParkMoffett FieldCAUSA

The overarching goal of this study was to perform a comprehensive metaanalysis of irrigated agricultural Crop Water Productivity(CWP)of the world’s three leading crops:wheat,corn,and rice based on three decades of remote sensing and non-remote sensing-based ***,CWP data from 148 crop growing study sites(60 wheat,43 corn,and 45 rice)spread across the world were gathered from published articles spanning 31 different *** was overwhelming evidence of a significant increase in CWP with an increase in latitude for predominately northern hemisphere *** example,corn grown in latitude 40–50°had much higher mean CWP(2.45 kg/m^(3))compared to mean CWP of corn grown in other latitudes such as 30–40°(1.67 kg/m^(3))or 20–30°(0.94 kg/m^(3)).The same trend existed for wheat and rice as *** soils,none of the CWP values,for any of the three crops,were statistically ***,mean CWP in higher latitudes for the same soil was significantly higher than the mean CWP for the same soil in lower *** applied for all three crops *** wheat,the global CWP categories were low(≤0.75 kg/m^(3)),medium(>0.75 to1.25 to≤1.75 kg/m^(3)),and high(>1.75 kg/m^(3)).For rice the global CWP categories were low(≤0.70 kg/m^(3)),medium(>0.70 to≤1.25 kg/m^(3)),and high(>1.25 kg/m^(3)).USA and China are the only two countries that have consistently high CWP for wheat,corn,and *** and India have medium CWP for wheat and ***’s corn,however,has low ***,Turkey,Netherlands,Mexico,and Israel have high CWP for ***,Argentina,and Hungary have high CWP for corn,and Philippines has high CWP for *** other countries have either low or medium CWP for all three *** on data in this study,the highest consumers of water for crop production also have the most potential for water *** countries are USA

关键词： Crop water productivity sustainable agriculture water use/water savings wheat corn rice food and water security

Soil water content and nitrogen differentially correlate with multidimensional leaf traits of two temperate broadleaf species

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Plant Diversity 2023年第6期45卷 694-701页

作者： Ming-Yue jin daniel j.johnson Guang-Ze jin Qing-Xi Guo Zhi-Li Liu Center for Ecological Research Key Laboratory of Sustainable ForestEcosystem Management-Ministry of EducationNortheast Asia Biodiversity Research CenterNortheast Forestry UniversityHarbin 150040HeilongjiangChina School of Forest Resources and Conservation University of FloridaGainesvilleFLUSA

The variation and correlation of leaf economics and vein traits are crucial for predicting plant ecological strategies under different environmental ***,correlations between these two suites of traits and abiotic factors such as soil water and nitrogen content remain *** measured leaf economics and vein traits as well as soil water and nitrogen content for two different shade-tolerant species(Betula platyphylla and Acer mono)in four mixed broadleaved-Korean pine(Pinus koraiensis)forests along a latitudinal gradient in Northeast *** found that leaf economics traits and vein traits were decoupled in shade-intolerant species,Betula platphylla,but significantly coupled in a shadetolerant species,*** found stronger correlations among leaf traits in the shade tolerant species than in the shade intolerant ***,leaf economic traits were positively correlated with the soil water gradient for both species,whereas vein traits were positively correlated with soil water gradient for the shade intolerant species but negatively correlated in the shade tolerant *** economic traits were positively correlated with soil nitrogen gradient in shade intolerant species but not correlated in shade tolerant species,vein traits were negatively correlated with soil nitrogen gradient in shade tolerant species but not correlated in shade intolerant *** study provides evidence for distinct correlations between leaf economics and vein traits and local abiotic factors of species differing in light *** recommend that the ecological significance of shade tolerance be considered for species when evaluating ecosystem functions and predicting plant responses to environmental changes.

关键词： Leaf trait multidimensionality Economics traits Vein traits Soil water content Soil total nitrogen Shade tolerance

Low-cost Position and Force Measurement System for Payload Transport Using UAVs

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International journal of Automation and computing 2021年第4期18卷 594-604页

作者： daniel Ceferino Gandolfo Claudio D.Rosales Lucio R.Salinas j.Gimenez Ricardo Carelli Institute of Automation(INAUT) National University of San Juan-CONICETSan Juan J5400ARLArgentina

In recent years, multiple applications have emerged in the area of payload transport using unmanned aerial vehicles(UAVs). This has attracted considerable interest among the scientific community, especially the cases involving one or several rotarywing UAVs. In this context, this work proposes a novel measurement system which can estimate the payload position and the force exerted by it on the UAV. This measurement system is low cost, easy to implement, and can be used either in indoor or outdoor environments(no sensorized laboratory is needed). The measurement system is validated statically and dynamically. In the first test, the estimations obtained by the system are compared with measurements produced by high-precision devices. In the second test, the system is used in real experiments to compare its performance with the ones obtained using known procedures. These experiments allowed to draw interesting conclusions on which future research can be based.

关键词： Payload transport unmanned aerial vehicle(UAV) measurement system path following controller low-cost system

Effects of underground explosions on soil and structures

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Underground Space 2020年第4期5卷 324-338页

作者： daniel Ambrosini Bibiana Luccioni National University of Cuyo CONICETArgentina National University of Tucuman CONICETArgentina

Much effort has been dedicated to the study of underground explosions because they pose a major threat to people and structures below or above the *** this regard,it is especially important to model the propagation of blast waves in soil and their effects on *** main phenomena caused by underground explosive detonation that must be addressed are crater or camouflet formation,shock wave and elastic–plastic wave propagation in soil,and soil-structure *** phenomena can be numerically simulated using hydrocodes,but much care must be taken to obtain reliable *** objective of this study is to analyze the ability of a hydrocode and simple soil models that do not require much calibration to approximately reproduce experimental and empirical results related to different buried blast events and to provide general guidelines for the simulation of this type of *** this regard,crater formation,soil ejecta,blast wave propagation in soil,and their effects on structures below and above the ground are numerically simulated using different soil models and parameters;the results are *** properties of soil have a significant effect on structures,the ejecta,and the propagation of shock waves in ***,the model of the soil to study these phenomena must be carefully *** their effect on the diameter of a crater is insignificant.

关键词： Shock waves Underground explosions Soils Hydrocodes

Quantitative analysis of morphometry on Ribb and Gumara watersheds: Implications for soil and water conservation

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International Soil and Water Conservation Research 2019年第2期7卷 150-157页

作者： daniel Asfaw Getachew Workineh Debre Tabor University Department of Geography and Environmental Studies Ethiopia Debre Tabor University Department of Geography and Environmental Studies Ethiopia

Morphometric analysis is a quantitative measurement and mathematical analysis of *** plays a significant role in understanding the geohydrological characteristics of a drainage basin in relation to the terrain feature and its flow *** also helps to estimate the incidence of infiltration and runoff,and other related hydrological character of a watershed like erosion and sediment transport which has a strong implication for natural resource *** study has attempted to quantify the morphometric characteristics of Guna-Tana watershed for proper implementation of soil and water conservation *** (DEM) was used for extracting morphometric *** watershed covers a total area of 3601.5 km2 and it has a basin length of 78.89 *** has been tried to generate morphometric parameters which account basin drainage network,geometry,drainage texture,and relief characteristics together with hypsometric *** morphometric analysis of drainage density of the study watershed is 0.49 km/km2 which indicates the basin is highly permeable and result with better underground water storage *** number is 0.02 that implies the area is less prone to soil *** addition,it has stream frequency of 0.32 and form factor 0.57 which indicates slightly elongated basin *** analysis of its sub watersheds Gumara and Ribb was also ***,practicing soil and water conservation in the watershed could enhance/strengthen the water storage capacity,prevent sediment loss and related natural resource from the watershed that rehabilitate its productivity.

关键词： Morphometric analysis Drainage density Guna-Tana watershed Soil and water conservation

Coherent vorticity dynamics and dissipation in a utility-scale wind turbine wake with uniform inflow

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Theoretical & Applied Mechanics Letters 2021年第5期11卷 266-272页

作者： daniel Foti Department of Mechanical Engineering University of MemphisMemphisTNUSA

The vorticity dynamics and its relationship to dissipation in the wake of a utility-scale wind turbine are investigated through large-eddy *** vorticity dynamics is assessed through the enstrophy,which is related to the turbulent *** averaged enstrophy and turbulent dissipation are shown to be quantitatively similar in the *** temporal phase averaging,the vorticity fluctuations are decomposed into coherent and random fluctuations with respect to the frequency of the tip *** enstrophy in the tip vortices is dominated by coherent fluctuations,while the coherent fluctuations of root vortices are immediately saturated by the random vorticity fluctuations of the unstable hub *** coherent strain rate has significant differences com pared to the coherent enstrophy within one diameter downwind of blade tip,but the random enstrophy and strain rate are relatively *** in coherent enstrophy and strain rate decrease further from the rotor.

关键词： Wind turbine wake Coherent structures Vorticity dynamics