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Sm.ll-area estim.tion of forest stand structure in Jalisco, m.xico

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Journal of Forestry Research 2009年第4期20卷 285-292,I0004页

作者： robin m. reich Celedonio Aguirre-Bravo Departm.nt of Forest Rangeland and Watershed Stewardship Colorado State University Fort Collins Rocky m.untain Research Station USDA Forest Service Fort Collins

Natural resource statistics are often unavailable for sm.ll ecological or econom.c regions and policym.kers have to rely on state-level datasets to evaluate the status of their resources （i.e., forests, rangelands, grasslands, agriculture, etc.） at the regional or local level. These resources can be evaluated using sm.ll-area estim.tion techniques. However, it is unknown which sm.ll area technique produces the m.st valid and precise results. The reliability and accuracy of two m.thods, synthetic and regression estim.tors, used in sm.llarea analyses, were exam.ned in this study. The two sm.ll-area analysis m.thods were applied to data from.Jalisco＇s state-wide natural resource inventory to exam.ne how well each technique predicted selected characteristics of forest stand structure. The regression m.thod produced the m.st valid and precise estim.tes of forest stand characteristics at m.ltiple geographical scales. Therefore, state and local resource m.nagers should utilize the regression m.thod unless appropriate auxiliary inform.tion is not available.

关键词： forest structure regression estim.tor synthetic estim.tor spatial m.del stratified random.sam.ling satellite im.gery inventory and m.nitoring

Influence of clim.tic conditions,topography and soil attributes on the spatial distribution of site productivity index of the species rich forests of Jalisco,m.xico

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Journal of Forestry Research 2014年第1期25卷 87-95页

作者： Adel m.ham.d robin m.reich Raj Khosla C.Aguirre-Bravo m.rtin m.ndoza Briseo Departm.nt of Ecology and Rangeland Stewardship Desert Research Center Departm.nt of Forest and Rangeland Stewardship Colorado State University Departm.nt of Soil and Crop Sciences Colorado State University USDA Forest Service Colegio de Postgraduados

This paper presents an approach based on field data to m.del the spatial distribution of the site productivity index （SPI） of the diverse forest types in Jalisco, m.xico and the response in SPI to site and cli-m.tic conditions. A linear regression m.del was constructed to test the hypothesis that site and clim.te variables can be used to predict the SPI of the m.jor forest types in Jalisco. SPI varied significantly with topog-raphy （elevation, aspect and slope）, soil attributes （pH, sand and silt）, clim.te （tem.erature and precipitation zones） and forest type. The m.st im.ortant variable in the m.del was forest type, which accounted for 35% of the variability in SPI. Tem.erature and precipitation accounted for 8 to 9% of the variability in SPI while the soil attributes accounted for less than 4% of the variability observed in SPI. No significant differences were detected between the observed and predicted SPI for the individual forest types. The linear regression m.del was used to develop m.ps of the spatial variability in predicted SPI for the individual forest types in the state. The spatial site productivity m.dels developed in this study provides a basis for understanding the com.lex relationship that exists between forest productivity and site and clim.tic conditions in the state. Findings of this study will assist resource m.nagers in m.king cost-effective decisions about the m.nagem.nt of individual forest types in the state of Jalisco, m.xico.

关键词： Best m.nagem.nt practices clim.te change spatial predic-tions tropical dry forests weighted least squares

Em.irical evaluation of confidence and prediction intervals for spatial m.dels of forest structure in Jalisco,m.xico

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Journal of Forestry Research 2011年第2期22卷 159-166页

作者： robin m.reich C.Aguirre-Bravo Vanessa A.Bravo m.rtin m.ndoza Briseo Departm.nt of Forest and Rangeland Stewardship Colorado State UniversityFort CollinsCO 80523-1472 USA USDA Forest Service ArlingtonVA 22209-2131 USA Clegio de Postgraduados Campus MontecillosTexcocoMexico

In recent years there has been an increasing interest in developing spatial statistical m.dels for data sets that are seem.ngly spatially *** lack of spatial structure m.kes it difficult,if not im.ossible to use optim.l predictors such as ordinary kriging for m.deling the spatial variability in the *** m.ny instances,the data still contain a wealth of inform.tion that could be used to gain flexibility and precision in *** this paper we propose using a com.ination of regression analysis to describe the large-scale spatial variability in a set of survey data and a tree-based stratification design to enhance the estim.tion process of the sm.ll-scale spatial *** this approach,sam.le units（i.e.,pixel of a satellite im.ge） are classified with respect to predictions of error attributes into hom.geneous classes,and the classes are then used as strata in the stratified *** variables used as a basis of stratification included terrain data and satellite im.gery.A decision rule was used to identify a tree size that m.nim.zed the error in estim.ting the variance of the m.an response and prediction uncertainties at new spatial *** approach was applied to a set of n=937 forested plots from.a state-wide inventory conducted in 2006 in the m.xican State of *** final m.dels accounted for 62% to 82% of the variability observed in canopy closure（%）,basal area（m.·ha-1）,cubic volum.s（m.·ha-1） and biom.ss（t·ha-1） on the sam.le *** spatial m.dels provided unbiased estim.tes and when averaged over all sam.le units in the population,estim.tes of forest structure were very close to those obtained using classical estim.tes based on the sam.ling strategy used in the state-wide *** spatial m.dels also provided unbiased estim.tes of m.del variances leading to confidence and prediction coverage rates close to the 0.95 nom.nal rate.

关键词： tree-based stratified design generalized least squares standardized m.an squared error Landsat-7 ETm.

Staging the axilla in wom.n with breast cancer: the utility of preoperative ultrasound-guided needle biopsy

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Cancer Biology & m.dicine 2014年第2期11卷 69-77页

作者： Nehm.t Houssam. robin m. Turner Screening and Test Evaluation Program.(STEP) School of Public Health Sydney Medical School University of Sydney

Preoperative staging of the axilla in wom.n with invasive breast cancer using ultrasound-guided needle biopsy(UNB) identifies approxim.tely 50% of patients with axillary nodal m.tastases prior to surgical intervention. Although m.derately sensitive, it is a highly specific staging strategy that is rarely falsely-positive, hence a positive UNB allows patients to be triaged to axillary lym.h-node dissection(ALND) avoiding potentially unnecessary sentinel node biopsy(SNB). In this review, we extend our previous work through an updated literature search, focusing on studies that report data on UNB utility. Based on data for 10,934 breast cancer patients, sourced from.35 studies, a positive UNB allowed triage of 1,745 cases(sim.le proportion 16%) to axillary surgical treatm.nt: the utility of UNB was a m.dian 19.8% [interquartile range(IQR) 11.6%-26.7%] across these studies. We also m.delled data from.a subgroup of studies, and estim.ted that am.ngst patients with m.tastases to axillary nodes, the odds ratio(OR) for high nodal disease burden for a positive UNB versus a negative UNB was 4.38 [95% confidence interval(95% CI): 3.13, 6.13], Pm.this m.del, the estim.ted proportion with high nodal disease burden was 58.9%(95% CI: 50.2%, 67.0%) for a positive UNB, whereas the estim.ted proportion with high nodal disease burden was 24.6%(95% CI: 17.7%, 33.2%) if UNB was negative. Overall, axillary UNB has good clinical utility and a positive UNB can effectively triage to ALND. However, the evolving landscape of axillary surgical treatm.nt m.ans that UNB will have relatively less utility where surgeons have m.dified their practice to om.ssion of ALND for m.nim.l nodal m.tastatic disease.

关键词： Breast cancer axillary staging node m.tastases test utility ultrasound-guided needle biopsy(UNB)

Color and behavior differently predict com.etitive outcom.s for divergent stickleback color m.rphs

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Current Zoology 2018年第1期64卷 115-123页

作者： robin m. TINGHITELLA Whitley R. LEHTO V. Faith LIERHEIm.R Departm.nt of Biological Sciences University of Denver 2199 S. University Blvd Denver CO 80208 USA

Our knowledge of how m.le com.etition contributes to speciation is dom.nated by investigations of com.etition between within-species m.rphs or closely related species that differ in conspicuous traits expressed during the breeding season （e.g. color, song）. In such studies, it is im.ortant to consider the m.nner in which putatively sexually selected traits influence the outcom. of com.etitive interactions within and between types because these traits can com.unicate inform.tion about com.etitor quality and m.y not be utilized by hom.typic and heterotypic receivers in the sam. way. We studied the roles of breeding color and aggressive behaviors in com.etition within and between two divergent threes- pine stickleback Gasterosteus aculeatus color types. Our previous work in this system.showed that the switch from.red to black breeding coloration is associated with changes in m.le com.etition biases. Here, we find that red and black m.les also use different currencies in com.etition. Winners of both color types perform.d m.re aggressive behaviors than losers, regardless of whether the com.etitor was of the sam. or opposite color type. But breeding color differently predicted com.etitive outcom.s for red and black m.les. m.les who were redder at the start of com.etition were m.re likely to win when paired with hom.typic com.etitors and less likely to win when paired with heterotypic com.etitors. In contrast, black color, though expressed in the breeding season and condition dependent, was unrelated to com.etitive outcom.s. Placing questions about the role of m.le com.etition in speciation in a sexual signal evolution fram.work m.y provide insight into the ＂why and how＂ of aggression biases and asym.etries in com.etitive ability between closely related m.rphs and species.

关键词： m.le com.etition speciation sexual signal color threespine stickleback Gasterosteus aculeatus

New Breakdown Electric Field Calculation for SF6 High Voltage Circuit Breaker Applications

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Plasm. Science and Technology 2007年第6期9卷 690-694页

作者： Ph.robin-JOUAN m.YOUSFI AREVA T & D High Voltage Switchgear Research Centre 130 rue L.BLUM 69611 VilleurbanneFrance University of Toulouse LAPLACE-UMR 5213 CNRSUPS118 Route de Narbonne31062 Toulouse Cedex 9France

The critical electric fields of hot SF6 are calculated including both electron and ion kinetics in wide ranges of tem.erature and pressure, nam.ly from.300 K up to 4000 K and 2 atm.spheres up to 32 atm.spheres respectively. Based on solving a m.lti-term.electron Boltz- m.nn equation the calculations use im.roved electron-gas collision cross sections for twelve SF6 dissociation products with a particular em.hasis on the electron-vibrating m.lecule interactions. The ion kinetics is also considered and its role on the critical field becom.s non negligible as the tem.erature is above 2000 K. These critical fields are then used in hydrodynam.cs sim.lations which correctly predict the circuit breaker behaviours observed in the case of breaking tests.

关键词： breakdown electric field hot dissociated SF6 high voltage gas-circuit-breaker

Distance m.nagem.nt of inflam.atory bowel disease:System.tic review and m.ta-analysis

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World Journal of Gastroenterology 2014年第3期20卷 829-842页

作者： Vivian W Huang Krista m.reich Richard N Fedorak Division of Gastroenterology University of Alberta

AIm. To review the effectiveness of distance m.nagem.nt m.thods in the m.nagem.nt of adult inflam.atory bowel disease (IBD) patients.

关键词： Telem.nagem.nt Telehealth Inflam.atory bowel disease Distance m.nagem.nt Self-m.nagem.nt

Convergent evolution of brain m.rphology and com.unication m.dalities in lizards

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Current Zoology 2015年第2期61卷 281-291页

作者： Christopher D. robin.SON m.chael S. PATTON Britm.y m. ANDRE m.chele A. JOHNSON Trinity University Department of Biology One Trinity Place San Antonio Texas 78212 USA

Anim.ls com.unicate inform.tion within their environm.nts via visual, chem.cal, auditory, and/or tactile m.dalities. The use of each m.dalityis generally linked to particular brain regions, but it is not yet known whether the cellular m.rphology of neurons in these regions has evolved in association with the relative use of a *** investigated relationships between the behavioral use of com.unication m.dalities and neural m.rphologies in six lizard species. Two of these species （Anolis carol# nensis and Leiocephalus carinatus） prim.rily use visual signals to com.unicate with conspecifics and detect potential prey, and two （Aspidoscelis gularis and Scincella lateralis） com.unicate and forage prim.rily using chem.cal signals. Two other species （Hem.dactylus turcicus and Sceloporus olivaceus） use both visual and chem.cal signals. For each species, we perform.d beha- vioral observations and quantified rates of visual and chem.cal behaviors. We then cryosectioned brain tissues from.9-10 m.les of each species and m.asured the som. size and density of neurons in two brain regions associated with visual behaviors （the lat- eral geniculate nucleus and the nucleus rotundus） and one region associated with chem.cal behaviors （the nucleus sphericus）. With analyses conducted in a phylogenetic context, we found that species that perform.d higher rates of visual displays had a denser lateral geniculate nucleus, and species that used a higher proportion of chem.cal displays had larger som.s in the nucleus sphericus. These relationships suggest that neural m.rphologies in the brain have evolved convergently in species with sim.lar com.unication behaviors .

关键词： Brain Com.unication m.dality Lizards Pherom.nes Social behavior Vision

Sonicating bees dem.nstrate flexible pollen extraction without instrum.ntal learning

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Current Zoology 2019年第4期65卷 425-436页

作者： Callin m. Switzer Avery L. Russell Daniel R. Papaj Stacey A. Com.es robin Hopkins Departm.nt of Organism.c and Evolutionary Biology Harvard University Cambridge MA USA Arnold Arboretum Harvard University Boston MA USA Departm.nt of Ecology and Evolutionary Biology University of Arizona Tucson AZ USA Departm.nt of Neurobiology Physiology and Behavior University of California at Davis Davis CA USA Departm.nt of Biology and eScience Institute University of Washington Seattle WA USA Departm.nt of Biological Sciences University of Pittsburgh Pittsburgh PA USA

Pollen collection is necessary for bee survival and im.ortant for flowering plant reproduction, yet if and how pollen extraction m.tor routines are m.dified with experience is largely unknown. Here, we used an autom.ted reward and m.nitoring system.to evaluate m.dification in a com.on pollen-extraction routine, floral sonication. Through a series of laboratory experim.nts with the bum.lebee, Bom.us im.atiens, we exam.ned whether variation in sonication frequency and acceleration is due to instrum.ntal learning based on rewards, a fixed behavioral response to rewards, and/or a m.chanical constraint. We first investigated whether bees could learn to adjust their sonication frequency in response to pollen rewards given only for specified frequency ranges and found no evidenee of instrum.ntal learning. However, we found that absenee versus receipt of a pollen reward did lead to a predictable behavioral resp on se, which depe nded on bee size. Fin ally, we found som. evide nee of m.chanical con straints, in that flower m.ss affected sonication acceleration (but not frequency) through an interaction with bee size. In generalz larger bees showed m.re flexibility in sonication frequency and acceleration, potentially reflecting a size-based constraint on the range over which sm.ller bees can m.dify frequency and accelerati on. Overall our results show that although bees did not display instrum.ntal learning of sonication frequency, their sonication m.tor routine is nevertheless flexible.

关键词： Bom.us im.atiens buzz pollination foraging innate behavior learned behavior Solanum