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survival and growth of dominant tree seedlings in seasonally tropical dry forests of Yucatan: site and fertilization effects

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Journal of Plant Ecology 2014年第5期7卷 470-479页

作者： Luis salinas-Peba Víctor Parra-Tabla Julio Campo Miguel A.Munguía-Rosas Departamento de Ecología Tropical Campus de Ciencias Biológicas y AgropecuariasUniversidad Autónoma de YucatánKm.15.5 Carretera Mérida-XmatkuilYucatán 97000México Instituto de Ecología Universidad Nacional Autónoma de MéxicoA.p.70-275México D.F.04510México Departamento de Ecología humana Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional(CINVESTAV)Km.6 Antigua carretera a ProgresoMérida 97310México

Aims seasonally tropical dry forests of the Yucatan Peninsula are typically found in sites with nutrient-poor soils because of the recent geologi-cal origin of the *** landscape is dominated by extensive karstic plates that shape environments where vegetation regenera-tion through seed germination may be limited by the availability of suitable *** this study,we documented the survival and growth of seedlings from three dominant tree species(Bursera simaruba,Piscidia piscipula and Lysiloma latisiliquum)in seasonally tropical dry forests in ***,we evaluated the effect of nutrient addition(N and P,separately and in combination)on seedling survival and growth across three sites with differing levels of *** We conducted a nutrient addition experiment,whereby we estab-lished 12 plots of dimensions 10×10 m(100 m^(2))at each site,from which three plots were randomly selected to receive one of four treatments:N addition,P addition,N and P addition and no nutri-ent addition(controls).Prior to treatment application,in each plot,we planted 10 seedlings of each species in October 2010 and sub-sequently conducted surveys of plant growth and survival every 20 days from November 2010 to April *** Findings Overall,nutrient addition increased seedling survival and the mag-nitude of this effect was similar among *** did not observe an additive effect of the N+P treatment on ***,we observed a positive effect of nutrient addition on seedling growth,but this effect was contingent upon site;regarding survival,the effects of N and P on seedling growth were not *** results suggest that seedling recruitment and growth in the three dominant species of trees in Yucatan are limited by nutrient avail-ability but that the magnitude of this effect,particularly on seedling growth,is specific for species and site.

关键词： growth nitrogen nutrient addition phosphorus seedling survival seasonally tropical dry forest

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Population dynamics of three lizard species from the genus sceloporus:short-term changes in demographic parameters

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Integrative Zoology 2019年第6期14卷 542-560页

作者： selene VARGAs-GARCÍA Víctor ARGAEZ Israel sOLANO-ZAVALETA J.Jaime ZÚÑIGA-VEGA Graduate Program in Biological sciences National Autonomous University of MexicoUniversity CityMexico CityMéxico Department of Ecology and Natural Resources Faculty of SciencesNational Autonomous University of MexicoUniversity CityMexico CityMéxico.

Most demographic studies focus on numerical changes that occur within populations across ***,typically studies at an interannual scale do not provide information on the particular times of the year(particular months or seasons)when rates of survival,recruitment,or migration increase or decrease due to physiological,behavioral or ecological *** monthly or seasonal changes in demographic parameters may lead to substantial variations in population *** this study,we collected capture-mark-recapture data on 3 species of lizards of the genus sceloporus(sceloporus torquatus,sceloporus grammicus and sceloporus megalepidurus)found in ecologically similar habitats to examine potential changes in demographic rates among 3 different climatic seasons:rainy,cold-dry and warm-dry *** tested different hypotheses about the effect of these seasons on survival,recruitment of new adults,and temporary *** found that during the season with severe thermal constraints,the cold-dry season,survival of *** decreased *** also detected a considerable increase in the recruitment rate of *** during the rainy season,when these lizards are establishing territories and finding *** contrast,we found no evidence of intra-annual changes in the rate of temporary *** addition,we calculated abundance and population growth rates for each species and for each *** study represents a significant contribution to the understanding of intra-annual demographic variation in lizards.

关键词： abundance recruitment sceloporus lizards survival temporary emigration

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Variable exponent hardy spaces associated with discrete Laplacians on graphs

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science China Mathematics 2019年第1期62卷 73-124页

作者： Víctor Almeida Jorge J.Betancor AlejANDro J.Castro Lourdes Rodríguez-Mesa Departamento de Análisis Matemático Universidad de La Laguna Department of Mathematics Nazarbayev University

In this paper we develop the theory of variable exponent hardy spaces associated with discrete Laplacians on infinite graphs. Our hardy spaces are defined by square integrals, atomic and molecular decompositions. Also we study boundedness properties of Littlewood-Paley functions, Riesz transforms, and spectral multipliers for discrete Laplacians on variable exponent hardy spaces.

关键词： graphs discrete Laplacian hardy spaces variable exponent square functions spectral multipliers

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Neutral protamine hagedorn/regular insulin in the treatment of inpatient hyperglycemia: Comparison of 3 basal-bolus regimens

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World Journal of Diabetes 2017年第10期8卷 455-463页

作者： Dania Lizet Quintanilla-Flores JoséGerardo González-González Guillermo García-De la Cruz héctor Eloy Tamez-Pérez Department of Internal Medicine 'Dr. José Eleuterio González' University HospitalUniversidad Autónoma de Nuevo León Endocrinology service 'Dr. José Eleuterio González' University HospitalUniversidad Autónoma de Nuevo León school of Medicine Universidad Autónoma de Nuevo León Research Division School of MedicineUniversidad Autónoma de Nuevo León

AIM To compare the safety and efficacy or 3 basal-bolus regimens of neutral protamine hagedorn(NPh)/regular insulin in the management of inpatient *** We randomized 105 patients with blood glucose levelsbetween 140 and 400 mg/dL to a basal-bolus regimen of NPh insulin given once(n = 30), twice(n = 40) or three times(n = 35) daily, in addition to pre-meal regular insulin. Major outcomes included were differences in glycemic control, frequency of hypoglycemia and total insulin *** NPh insulin given in a once-daily regimen was associated with better glycemic control(58.3%) compared to twice daily(42.4%) and three times daily(48.9) regimens(P = 0.031). The frequency of hypoglycemia was similar between the three groups(2.0%, 0.7% and 1.2%, P = 0.21). The mean insulin dose at discharge was 0.48 ± 0.14 U/kg in the once-daily group compared to 0.69 ± 0.28 in the twice-daily, and 0.65 ± 0.20 in the three times daily regimens(P sION NPh insulin administered in a once-daily regimen resulted in improvement in glycemic control with similar rates of hypoglycemia compared to a twice-daily and a three times-daily regimen. Further studies are needed to evaluate whether this regimen could be implemented in all hospitalized patients with hyperglycemia.

关键词： Neutral protamine hagedorn insulin hospital hyperglycemia Basal-bolus regimen Type 2 diabetes mellitus Inpatient care units

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Detection of integron integrase genes on King George Island, Antarctica

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Advances in Polar science 2015年第1期26卷 30-37页

作者： Verónica Antelo héctor Romero silvia Batista Unidad de Microbiología Molecular Biogem Instituto de Investigaciones Biológicas Clemente Estable (MEC) Departamento de Ecología y Evolución Facultad de Ciencias UDeLaR Montevideo C.P.11400 Uruguay

The presence and diversity of class 1 integrase gene （intl） sequences were evaluated by PCR using previously designed primers. Two clone libraries were constructed from DNA in sediment and microbial mat samples collected on Fildes Peninsula, King George Island, *** libraries constructed from samples collected at halfthree Point （hP） and Norma Cove （NC） contained 62 and 36 partial intl sequences, respectively. These sequences clustered into 10 different groups with 〈 95% amino acid identity. Alignment of the deduced amino acid sequences with those from recognized integron-encoded integrases demonstrated the presence of highly conserved motifs characteristic of intl integrases. The hP library contained 42 nucleotide sequences identical to the class 1 intl gene found in a collection of trimethoprim-resistant （Tmpr） Antarctic Enterobacter sp. isolates, previously collected in the same area. These integrons, located on plasmids, had a genetic organization similar to that of pKOX105 from Klebsiella oxytoca. The 20 remaining hP and NC library sequences were similar to integrase sequences previously determined in a metagenomic analysis of environmental samples. We have demonstrated the presence of integron integrase genes in Antarctic sediment samples. About half these genes were very similar to the class 1 integrons found in human- associated microbiota, suggesting that they originated from human-dominated ecosystems. The remaining integrase genes were probably associated with endemic bacteria.

关键词： integrase amplicon library maritime Antarctica

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Multi-label Text Classification with a Robust Label Dependent Representation

Multi-label Text Classification with a Robust Label Dependen...

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2010 Third Pacific-Asia Conference on Web Mining and Web-based Application (WMWA 2010)

作者： Rodrigo Alfaro héctor Allende Departamento de Informática Universidad Técnica Federico Santa María and Escuela de Ingeniería Informática Pontificia Universidad Católica de Valparaíso Departamento de Informática Universidad Técnica Federico Santa María and Facultad de Ingeniería Universidad Adolfo Ibáez

ISBN: (纸本)9781424497232

Automatic text classification is the task of assigning unseen documents to a predefined set of classes or categories. Text Representation for classification have been traditionally approached with *** due to its simplicity and good performance. Multi-label automatic text classification has been traditionally tackled in the literature either by transforming the problem to apply binary techniques or by adapting binary algorithms to work with multiple labels. We present ***, a novel text representation for the multi-label classification approach. Our proposal focuses on modifying the data set input to the algorithm, differentiating the input by the label to evaluate. Performance of *** was tested with a known benchmark and compared to alternative techniques. The results show improvement compared to alternative approaches in terms of hamming loss.

关键词： Multi-label Text classification Text representation Machine learning.

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how does high-intensity intermittent training affect recreational endurance runners? Acute and chronic adaptations: A systematic review

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Journal of sport and health science 2017年第1期6卷 54-67页

作者： Felipe García-Pinillos Víctor M.soto-hermoso Pedro A.Latorre-Román Department of Corporal Expression University of Jaen Department of sports sciences University of Granada

Objective: This systematic review aimed to critically analyze the literature to determine how high-intensity intermittent training(hIIT) affects recreational endurance runners in the short-and ***: Electronic databases were searched for literature dating from January 2000 to October 2015. The search was conducted using the key words "high-intensity intermittent training" or "high-intensity interval exercise" or "interval running" or "sprint interval training" and "endurance runners" or "long distance runners". A systematic approach was used to evaluate the 783 articles identified for initial review. studies were included if they investigated hIIT in recreational endurance runners. The methodological quality of the studies was evaluated using the Physiotherapy Evidence Database(PEDro) scale(for intervention studies) and the modified Downs and Black Quality Index(for cross-sectional studies).Results: Twenty-three studies met the inclusionary criteria for review. The results are presented in 2 parts: cross-sectional(n = 15) and intervention studies(n = 8). In the 15 cross-sectional studies selected, endurance runners performed at least 1 hIIT protocol, and the acute impact on physiological, neuromuscular, metabolic and/or biomechanical variables was assessed. Intervention studies lasted a minimum of 4 weeks, with 10 weeks being the longest intervention period, and included 2 to 4 hIIT sessions per week. Most of these studies combined hIIT sessions with continuous run(CR) sessions; 2 studies' subjects performed hIIT ***: hIIT-based running plans(2 to 3 hIIT sessions per week, combining hIIT and CR runs) show athletic performance improvements in endurance runners by improving maximal oxygen uptake and running economy along with muscular and metabolic adaptations. To maximize the adaptations to training, both hIIT and CR must be part of training programs for endurance runners.

关键词： Endurance high-intensity training Intermittent exercises Interval running Long-distance runners Running

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Improvement in varistor properties of CaCu_(3)Ti_(1)O_(12) ceramics by chromium addition

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Journal of Materials science & Technology 2020年第6期41卷 12-20页

作者： Edson Cezar Grzebielucka Joao Frederico haas Leandro Monteiro Eder Carlos Ferreira de souza Christiane Philippini Ferreira Borges AndréVitor Chaves de Andrade Eloísa Cordoncillo héctor Beltrán-Mir sandra Regina Masetto Antunes Programa Pós-Graduacao em Química Aplicada Universidade Estadual de Ponta GrossaAv.Gen.Carlos Cavalcanti 474884.030-000Ponta GrossaParanáBrazil Programa de Pós-Graduacao em Ciências/Física Universidade Estadual de Ponta GrossaAv.Gen.Carlos Cavalcanti 474884.030-000Ponta GrossaParanáBrazil Dpto.de Química Inorgánica y Orgánica Universitat Jaume IAv.de Vicent Sos Baynats/n12071Castellón de la PlanaSpain

The effect of chromium addition on the structure and electrical properties of CaCu3Ti4O12 is *** based on the formula CaCu3Ti4-xCrxO12-σ(x = 0, 0.025, 0.050 and 0.075 mol%) are prepared by solid-state reaction. Pellets sintered at 1070℃ for 12 h are characterised by X-ray diffraction, scanning electron microscopy/energy dispersive spectroscopy and impedance spectroscopy. Current densityelectric field, dielectric loss and permittivity measurements are also carried out. Rietveld refinement showed the substitution of Cr(Ⅲ) on the Ti(Ⅳ) site, with the maximum substitution for x = 0.025 mol%.The generation of electrical defects in the grain boundary region by chromium doping is responsible for increasing the electric breakdown field strength and nonlinearity coefficient at room temperature from 1723 V/cm and 5.29 for x = 0 mol% to 3431 V/cm and 8.16 for x = 0.025 mol%. This composition shows the greatest improvement in ceramic varistor parameters.

关键词： CCTO structural analysis Impedance Varistor Rietveld

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Analysis of heterogeneous characteristics in a geothermal area with low permeability and high temperature

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Geoscience Frontiers 2017年第5期8卷 1039-1050页

作者： Alfonso Aragón-Aguilar Georgina Izquierdo-Montalvo siomara López-Blanco Víctor Arellano-Gómez Instituto Nacional de Electricidad y Energías Limpias Reforma 113 Col.Palmira Cuernavaca Morelos CP 62490 Mexico

An analytical methodology for reservoir characterization was applied in the central and southwestern zones of Los humeros geothermal field(LhGF). This study involves analysis of temperature, pressure,enthalpy and permeability in wells and their distribution along the area. The wells located in the central western side of the geothermal field are productive, whereas those located at the central-eastern side are non-productive. Through temperature profiles, determined at steady state in the analyzed wells, it was observed that at bottom conditions(approximately 2300 m depth), temperatures vary between 280 and360℃. The temperatures are higher at the eastern side of central zone of LhGF. A review of transient pressure tests, laboratory measurements of core samples, and correlation of circulation losses during drilling suggest that permeability of the formation is low. The enthalpy behavior in productive wells shows a tendency of increase in the steam fraction. It was found that productivity behavior has inverse relation with permeability of rock formation. Further, it is observed that an imbalance exists between exploitation and recharge. It is concluded from the results that the wells located at central-eastern area have low permeability and high temperature, which indicates possibility of heat storage.

关键词： Los humeros geothermal field Reservoir performance hot rock Enthalpy Permeability Recharge

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Diagnostic and therapeutic challenges of gastrointestinal angiodysplasias: A critical review and view points

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World Journal of Gastroenterology 2019年第21期25卷 2549-2564页

作者： Diego García-Compeán ángel N Del Cueto-Aguilera Alan R Jiménez-Rodríguez José A González-González héctor J Maldonado-Garza Gastroenterology service and Department of Internal Medicine Faculty of Medicine University Hospital "Dr. José E. González"Universidad Autónoma de Nuevo León

Gastrointestinal angiodysplasias (GIADs), also called angioectasias, are the most frequent vascular lesions. Its precise prevalence is unknown since most of them are asymptomatic. however, the incidence may be increasing since GIADs affect individuals aged more than 60 years and population life expectancy is globally increasing worldwide. They are responsible of about 5% to 10% of all gastrointestinal bleeding (GIB) cases. Most GIADs are placed in small bowel, where are the cause of 50 to 60% of obscure GIB diagnosed with video capsule endoscopy. They may be the cause of fatal severe bleeding episodes;nevertheless, recurrent overt or occult bleeding episodes requiring repeated expensive treatments and disturbing patient’s quality-of-life are more frequently observed. Diagnosis and treatment of GIADs (particularly those placed in small bowel) are a great challenge due to insidious disease behavior, inaccessibility to affected sites and limitations of available diagnostic procedures. hemorrhagic causality out of the actively bleeding lesions detected by diagnostic procedures may be difficult to establish. No treatment guidelines are currently available, so there is a high variability in the management of these patients. In this review, the epidemiology and pathophysiology of GIADs and the status in the diagnosis and treatment, with special emphasis on small bowel angiodysplasias based on multiple publications, are critically discussed. In addition, a classification of GIADs based on their endoscopic characteristics is proposed. Finally, some aspects that need to be clarified in future research studies are highlighted.

关键词： Angiodysplasias Angioectasias Vascular malformations Epidemiology Pathogenesis Endoscopic treatment somatostatin analogues

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