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The coexistence of baird’s tapir (Tapirus bairdii) and indigenous hunters in northeastern Honduras

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Integrative Zoology 2012年第4期7卷 429-438页

作者： Marc DUNN Nereyda estrada Derek A.SMITH Department of Geography and Environmental Studies Carleton UniversityOttawaOntarioCanada International Union for Conservation of Nature(IUCN)Honduras Tapir Specialist Group TegucigalpaHonduras

The baird’s tapir(Tapirus bairdii)is a popular game species throughout Central America,particularly among in-digenous populations,and is currently *** on Miskitu hunting was conducted over 4 months in a remote region in northeastern Honduras that overlaps with the Río Plátano biosphere *** hunting zone was mapped together with hunters and interviews were conducted with elders and other community mem-bers about tapir *** show that tapir harvesting is targeted toward specific habitats at specific times of *** rates for one year suggest that tapir hunting in the area exceeds estimates of maximum sustain-able ***,field surveys reveal the presence of tapir within 1 km of the community,and its harvest tends to be nearby,in both forested and agricultural landscapes,suggesting that the animal has not been depleted in the *** appears that the existence of forest areas adjacent to the hunting zone that do not experi-ence hunting,together with the anthropogenic habitats created through shifting cultivation,are factors that help explain the presence of tapirs in the *** article concludes with a discussion regarding the potential posi-tive role of indigenous hunters in tapir conservation throughout its distribution range.

关键词： baird’s tapir Honduras indigenous hunting Miskitu Río Plátano biosphere Reserve

Micromechanical adaptation as a treatment for spinal cord injury

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Neural Regeneration Research 2019年第11期14卷 1909-1911页

作者： Veronica estrada Hans werner Müller Molecular Neurobiology Laboratory Department of Neurology Heinrich-Heine-University Medical Center Düsseldorf

Spinal cord injury: Thus far injury of the spinal cord is incurable and, in the majority of cases, a devastating and life-changing event. The worldwide incidence rate of spinal cord injury (SCI) ranges from 250,000 to 900,000 (***, 2013;Kumar et al., 2018) new cases per year. SCI outcome includes the damage of axons, demyelination of axons, loss of signal transduction, and consequential long-lasting motor and sensory deficits. Additionally, the non-use of muscles can lead to atrophy and joint contractures, thereby further reducing the possibility of recovery. Depending on the spinal level and the severity of the injury, the extent of the damage can vary and spontaneous recovery is possible to varying degrees.

关键词： Micromechanical adaptation spinal cord injury spinal cord injury(SCI)

Changes in potential mammal diversity in national parks and their implications for conservation

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Current Zoology 2018年第6期64卷 671-679页

作者： Alba estrada A.Marcia bARbOSA Raimundo REAL biogeography Diversity and Conservation LabDepartment of Animal BiologyUniversidad de MalagaSpain Research Unit of biodiversity (UMIb UO-CSIC-PA)Oviedo Univ.-Campus MieresSpain CIbIO/InbIO-University of Evora Portugal

Observed species richness (OSR)is a widely used and well-studied biodiversity ***, non-observed species in favorable ecosystems are also *** metrics that include observed and potential species were recently defined:potential biodiversity (hereafter potential species richness--PSR)and geometric mean of favorabilities (GMF).We used these metrics to evaluate the national park network of mainland Spain at two time periods (2002 and 2015),using terrestrial mammals on a UTM 100-km^2 *** and GMF are based on the favorability function, a species distribution model that assesses how favorable an area is for the presence of a species, over and above its prevalence in the study *** each park and for the whole network,we calculated the mean and sum of OSR,PSR,and GMF in each time period,as well as changes between *** and PSR were higher inside than outside the park network in both time periods. Thus,although the network covers a very small proportion of the country,it performs well for the representation of mammal species and their favorable ***,mean PSR was lower in 2015 than in 2002 inside the national park network,whereas the opposite was the case outside the *** Parks generally not only concentrated highly favorable areas for mammals, but they also showed less favorable areas in 2015 compared to 2002,although the reduction was moderate to *** is a result to consider for future analyses because if the tendency increases, it may have consequences for the conservation of mammals and for the adequacy of the national park network.

关键词： conservation planning dark diversity environmental favorability potential biodiversity protected areas

Dynamic Simulation of Cracked buildings for Damage Detection

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Structural Durability & Health Monitoring 2020年第3期14卷 187-204页

作者： Alan Alonso-Rivers Rolando Salgado-estrada Faculty of Engineering Department of CivilAmbiental EngineeringSchool of Mining and Petroleum EngineeringUniversity of Alberta6361 Donadeo Innovation Center for Engineering(ICE)EdmontonAlbertaT6H 1H9Canada Faculty of Engineering of the Construction and the Habitat Campus VeracnuzUniversidad VeracruzanaBoca del RioVeracruzCP 94294México

A dynamic simulation method for cracked structures is implemented to determine their dynamic response with the purpose of evaluating their structural *** procedure makes possible the si mulation of three-dimensional cracked *** excitation force is randomly generated to simulate wind *** is assumed the structure remains in the elastic range,which allows for each mode that contributes to its dynamic response to be *** results indicate that the presence of damage causes changes in the modals parameters of the structure as accurate as other similar methods proposed for simpler ***,it is concluded that the proposed method is a reliable way to evaluate the dynamic behavior of three-dimensi onal cracked building structures.

关键词： Dynamic simulation cracked structures damage detection structural dynamic

Chiral Symmetry breaking for Fermions Charged under Large Lie Groups

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Communications in Theoretical Physics 2019年第4期71卷 410-416页

作者： Felipe J.Llanes-estrada Alexandre Salas-bernardez Depto.Fisica Teorica Universidad Complutense de Madrid

We reexamine the dynamical generation of mass for fermions charged under various Lie groups with equal charge and mass at a high Grand Uni?cation scale, extending the Renormalization Group Equations in the perturbativ... 详细信息

关键词： standard model group running fermion mass grand unification scale

Orientation effect on ground motion measurement for Mexican subduction earthquakes

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Earthquake Engineering and Engineering Vibration 2009年第1期8卷 1-16页

作者： H.P. Hong A. Pozos-estrada R. Gomez Department of Civil and Environmental Engineering University of Western Ontario Canada N6A 5B9 Institute of Engineering National Autonomous University of Mexico Mexico D.F.

The existence of the principal directions of the ground motion based on Arias intensity is well-known. These principal directions do not necessarily coincide with the orientations of recording sensors or with the orientations along which the ground motion parameters such as the peak ground acceleration and the pseudo-spectral acceleration （PSA） are maximum. This is evidenced by the fact that the maximum PSA at different natural vibration periods for horizontal excitations do not correspond to the same orientation. A recent analysis carried out for California earthquake records suggests that an orientation-dependent ground motion measurement for horizontal excitations can be developed. The main objective of this study is to investigate and provide seismic ground motion measurements in the horizontal plane, including bidirectional horizontal ground motions, for Mexican interplate and inslab earthquake records. Extensive statistical analyses of PSA are conducted for the assessment. The analysis results suggest that similar to the case of California records, the average behavior of the ratio of the PSA to the maximum resulting PSA can be approximated by a quarter of an ellipse in one quadrant; and that the ratio can be considered to be independent of the value of the maximum resulting PSA, earthquake magnitude, earthquake distance and the focal depth. Sets of response ratios and attenuation relationships that can be used to represent a bidirectional horizontal ground motion measurement for Mexican interplate and inslab earthquakes were also developed.

关键词： orthogonal horizontal excitations bidirectional ground motion measure attenuation relationship pseudospectral acceleration (PSA) response ratio Mexican earthquake

The use of intracorneal ring segments in keratoconus

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Eye and Vision 2016年第1期3卷 66-72页

作者： Alfredo Vega-estrada Jorge L.Alio Keratoconus Unit Vissum AlicanteCalle Cabanal1 Edificio Vissum03016 AlicanteSpain Division of Ophthalmology Universidad Miguel HernandezAlicanteSpain

Keratoconus is a corneal degeneration that usually appears during puberty and may seriously deteriorate the quality of life of the *** corneal disease is today the first indication of corneal transplantation in young *** the last decade of the XX century,keratoplasty procedures were the only alternative to treat this pathological *** the beginning of the XXI century,intracorneal ring segments implantation was proposed as a therapeutic choice for treating keratoconus *** then,several published articles have reported the benefits of this surgical procedure in treating this type of corneal ectatic *** purpose of the present investigative work is to summarize the characteristic of the intracorneal ring segments and also to review the different features published in the literature in relation to this surgical technique for the treatment of keratoconus patients.

关键词： Keratoconus Corneal ectasia Intracorneal rings

Harmonic Polynomials Via Differentiation

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Analysis in Theory and Applications 2018年第4期34卷 336-347页

作者： Ricardo estrada Department of Mathematics Louisiana State University

It is well-known that if p is a homogeneous polynomial of degree k in n variables, p ∈ P;, then the ordinary derivative p（）(r;) has the form A;Y（x）r;where A;is a constant and where Y is a harmonic homogeneous polynomial of degree k, Y ∈ H;, actually the projection of p onto H;. Here we study the distributional derivative p（）(r;) and show that the ordinary part is still a multiple of Y, but that the delta part is independent of Y, that is, it depends only on p-Y. We also show that the exponent 2-n is special in the sense that the corresponding results for p（）(r;)do not hold if α≠2-n. Furthermore, we establish that harmonic polynomials appear as multiples of r;when p（） is applied to harmonic multipoles of the form Y’（x）r;for some Y ∈H;.

关键词： Harmonic functions harmonic polynomials distributions multipoles

Insights into social relationships among female black howler monkeys Alouatta pigra at Palenque National Park, Mexico

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Current Zoology 2011年第1期57卷 1-7页

作者： Sarie VAN bELLE Alejandro estrada Karen b. STRIER Department of Zoology University of Wisconsin-Madison USA Estaclon de blologla Tropical Los Tuxtlas Instituto de Biologfa Universidad Nacional Autonoma de Mexico Mexico Department of Anthropology University of Wisconsin-Madison USA

Abstract We investigated the social relationships among adult females in two multimale-multifemale groups of black howler monkeys Alouatta pigra during a 14-month study in Palenque National Park, Mexico. based on over 900 focal hours and over 5400 scan samples recording neighboring group members, we found that females very rarely engaged in agonistic interactions and no dominance hierarchy could be discerned. Relationships among resident females were primarily affiliative, but females of one study group spent a higher proportion of time in close proximity and engaged in affiliative interactions with one another at higher rates than females in the other study group. The strength of female relationships increased with the birth of an infant. Al- though no females immigrated during the study period, the temporary association of three extragroup females with our study groups implies that the social system of black howler monkeys is more dynamic than previously suggested. These findings sug- gest that female black howler monkeys behave more similarly to female red howler monkeys A. seniculus than to female mantled howler monkeys A. palliata

关键词： black howler monkey Alouatta pigra Affiliation Agonism Female dispersal