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Influence of climatic conditions,topography and soil attributes on the spatial distribution of site productivity index of the species rich forests of Jalisco,Mexico

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

作者： Adel Mohamed Robin M.Reich Raj Khosla c.aguirre-bravo Martin Mendoza Briseo Department of Ecology and Rangeland Stewardship Desert Research Center Department of Forest and Rangeland Stewardship Colorado State University Department of Soil and crop Sciences Colorado State University USDA Forest Service colegio de Postgraduados

This paper presents an approach based on field data to model the spatial distribution of the site productivity index （SPI） of the diverse forest types in Jalisco, Mexico and the response in SPI to site and cli-matic conditions. A linear regression model was constructed to test the hypothesis that site and climate variables can be used to predict the SPI of the major forest types in Jalisco. SPI varied significantly with topog-raphy （elevation, aspect and slope）, soil attributes （pH, sand and silt）, climate （temperature and precipitation zones） and forest type. The most important variable in the model was forest type, which accounted for 35% of the variability in SPI. Temperature 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 model was used to develop maps of the spatial variability in predicted SPI for the individual forest types in the state. The spatial site productivity models developed in this study provides a basis for understanding the complex relationship that exists between forest productivity and site and climatic conditions in the state. Findings of this study will assist resource managers in making cost-effective decisions about the management of individual forest types in the state of Jalisco, Mexico.

关键词： Best management practices climate change spatial predic-tions tropical dry forests weighted least squares

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Empirical evaluation of confidence and prediction intervals for spatial models of forest structure in Jalisco,Mexico

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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 Martin Mendoza Briseo Department 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 models for data sets that are seemingly spatially *** lack of spatial structure makes it difficult,if not impossible to use optimal predictors such as ordinary kriging for modeling the spatial variability in the *** many instances,the data still contain a wealth of information that could be used to gain flexibility and precision in *** this paper we propose using a combination 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 estimation process of the small-scale spatial *** this approach,sample units（i.e.,pixel of a satellite image） are classified with respect to predictions of error attributes into homogeneous classes,and the classes are then used as strata in the stratified *** variables used as a basis of stratification included terrain data and satellite imagery.A decision rule was used to identify a tree size that minimized the error in estimating the variance of the mean 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 Mexican State of *** final models accounted for 62% to 82% of the variability observed in canopy closure（%）,basal area（m2·ha-1）,cubic volumes（m3·ha-1） and biomass（t·ha-1） on the sample *** spatial models provided unbiased estimates and when averaged over all sample units in the population,estimates of forest structure were very close to those obtained using classical estimates based on the sampling strategy used in the state-wide *** spatial models also provided unbiased estimates of model variances leading to confidence and prediction coverage rates close to the 0.95 nominal rate.

关键词： tree-based stratified design generalized least squares standardized mean squared error Landsat-7 ETM+

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墨西哥展叶松的地位指数和材积公式

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中南林业调查规划 1987年第2期 57-60页

作者： c.aguirre-bravo F.W.SMITH 刘安兴

导算树干材积、林分材积和地位指数的估算公式,是黑西哥展叶松(Pinus patula)在其天然分布区确定其生长和收获量的部分工作。数据收集于54种不同林分的162块样地。用chapman-Richards公式拟合优势高和林龄,获得了一簇同型的地位指数曲... 详细信息

导算树干材积、林分材积和地位指数的估算公式,是黑西哥展叶松(Pinus patula)在其天然分布区确定其生长和收获量的部分工作。数据收集于54种不同林分的162块样地。用chapman-Richards公式拟合优势高和林龄,获得了一簇同型的地位指数曲线。单株树干和林分材积公式适用的直径范围为15至80厘米。与南非发表的地位指数相比较,墨西哥展叶松由于天然更新而生长衰退,但也有可能是天然群体对非洲的异地栽培的遗传选择,墨西哥与非洲的树干材积公式是相同的。

关键词：林分材积地位指数曲线树干材积墨西哥拉丁美洲展叶松

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Navigating the controversy regarding antibiotic prophylaxis in acute variceal bleeding

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World Journal of Gastroenterology 2024年第18期30卷 2485-2487页

作者： David aguirre-Villarreal Ignacio García-Juárez Department of Gastroenterology and Liver Transplant Unit Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico

Antibiotic prophylaxis in patients with cirrhosis and acute variceal bleeding is part of the standard of care according to most clinical ***,with recent evidence arguing against antibiotic prophylaxis,the role of this... 详细信息

关键词： cirrhosis Acute variceal bleeding Antibiotic prophylaxis Endoscopic band ligation Spontaneous bacterial peritonitis

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Impact of an oligosaccharide-based polymer on the metabolic profiles and microbial ecology of weanling pigs experimentally infected with a pathogenic ***

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Journal of Animal Science and Biotechnology 2024年第2期15卷 749-764页

作者： Kwangwook Kim cynthia Jinno Xunde Li David bravo Eric cox Peng Ji Yanhong Liu Department of Animal Science University of CaliforniaDavisCA 95616USA Department of Animal Science Michigan State UniversityEast LansingMI 48824USA cedars-Sinai Medical center Los AngelesCA 90084USA School of Veterinary Medicine University of CaliforniaDavisCA 95616USA Pancosma|ADM 1180 RolleSwitzerland Nutreco Exploration NutrecoThe Netherlands Department of Virology Parasitology and ImmunologyGhent University9000 GhentBelgium Department of Nutrition University of CaliforniaDavisCA 95616USA

Background Our previous study has reported that supplementation of oligosaccharide-based polymer enhances gut health and disease resistance of pigs infected with enterotoxigenic ***(ETEc)F18 in a manner similar to *** objective of this study was to investigate the impacts of oligosaccharide-based polymer or antibiotic on the host metabolic profiles and colon microbiota of weaned pigs experimentally infected with ETEc *** Multivariate analysis highlighted the differences in the metabolic profiles of serum and colon digesta which were predominantly found between pigs supplemented with oligosaccharide-based polymer and *** relative abundance of metabolic markers of immune responses and nutrient metabolisms,such as amino acids and carbohydrates,were significantly differentiated between the oligosaccharide-based polymer and antibiotic groups(qchange>2.0).In addition,pigs in antibiotic had a reduced(Pce of Lachnospiraceae and Lactobacillaceae,whereas had greater(Pclostridiaceae and Streptococcaceae in the colon digesta on d 11 post-inoculation(PI)compared with d 5 *** The impact of oligosaccharide-based polymer on the metabolic and microbial profiles of pigs is not fully understood,and further exploration is ***,current research suggest that various mechanisms are involved in the enhanced disease resistance and performance in ETEc-challenged pigs by supplementing this polymer.

关键词： carbadox colon microbiota Enterotoxigenic E.coli F18 Metabolomics Oligosaccharide-based polymer Weaned pigs

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Z-Score in Fetal Echocardiography–Is there Still Room for New Studies?

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congenital Heart Disease 2024年第3期19卷 305-314页

作者： Marcio Fragoso Vieira Nathalie Jeanne bravo-Valenzuela Edward Araujo Júnior Department of Obstetrics Paulista School of MedicineFederal University of São Paulo(EPM-UNIFESP)São Paulo-SP04023-062Brazil Department of Obstetrics Federal University of Ceará(UFC)Sobral-CE60020-181Brazil Department of Pediatrics Pediatric CardiologySchool of MedicineFederal University of Rio de Janeiro(UFRJ)Rio de Janeiro-RJ21941-853Brazil

congenital heart disease(cHD)is the most common type of birth defect,representing a significant cause of peri-natal morbidity and *** diagnosis of such anomalies is crucial for improving *** pro-tocols recommend a qualitative assessment of cardiac structures using two-dimensional ultrasound(2DUS)and color Doppler *** cases of suspected abnormalities,quantitative assessments through cardiac structure measurements and reference curves can aid in accurate *** to centiles widely employed in obste-trics,Z-scores provide more precise quantification of various cardiac structures,particularly at the extremes of the *** the development of reference curves and Z-scores has progressed over the past two decades,a lack of standardization in measurements and statistical methodology for their determination is *** reference curves requires adherence to specific recommendations to improve their *** purpose of this study is to provide a narrative review of the major studies that have generated reference values for cardiac struc-tures using 2DUS and Z-scores,to evaluate their methodology,and to provide a summary of the results.

关键词： Z-scores reference ranges fetal echocardiography

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Accuracy of tree mapping based on hand-held laser scanning comparing leaf-on and leaf-off conditions in mixed forests

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Journal of Forestry Research 2024年第5期35卷 14-25页

作者： Frederico Tupinambá-Simões Adrián Pascual Juan Guerra-Hernández cristóbal Ordóñez Tiago de conto Felipe bravo iuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIAValladolidSpain Department of Geographical Sciences University of MarylandCollege ParkMD 20742USA Forest Research centre School of AgricultureUniversity of LisbonTapada da Ajuda1349‑017 LisbonPortugal

The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3D structures at high *** confirm the con-sistency in the retrieval of forest structural parameters using hand-held laser scanning(HLS),before operationalizing the method,confirming the data is *** analyzed the per-formance of tree-level mapping based on HLS under differ-ent phenology conditions on a mixed forest in western Spain comprising Pinus pinaster and two deciduous species,Alnus glutinosa and Quercus *** area was surveyed twice during the growing season(July 2022)and once in the deciduous season(February 2022)using several scan-ning *** reference data(418 trees,15 snags)was used to calibrate the HLS data and to assess the influence of phenology when converting 3D data into tree-level attrib-utes(DBH,height and volume).The HLS-based workflow was robust at isolating tree positions and recognizing stems despite changes in ***-six percent of all pairs matched below 65 *** DBH,phenology barely altered *** observed a strong agreement when comparing HLS-based tree height *** values exceeded 2 m when comparing height measurements,confirming height data should be carefully used as reference in remote sensing-based inventories,especially for deciduous *** volume was more precise for pines(r=0.95,and rela-tive RMSE=21.3–23.8%)compared to deciduous species(r=0.91–0.96,and relative RMSE=27.3–30.5%).HLS data and the forest structural complexity tool performed remark-ably,especially in tree positioning considering mixed forests and mixed phenology conditions.

关键词： Precision forestry Forest monitoring Mobile laser scanning Forest inventory

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A Value for Games Defined on Graphs

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Applied Mathematics 2024年第5期15卷 331-348页

作者： Néstor bravo Departamento de Matemá ticas Universidad de Guanajuato Guanajuato Mexico

Given a graph g=( V,A ) , we define a space of subgraphs M with the binary operation of union and the unique decomposition property into blocks. This space allows us to discuss a notion of minimal subgraphs (minimal coalitions) that are of interest for the game. Additionally, a partition of the game is defined in terms of the gain of each block, and subsequently, a solution to the game is defined based on distributing to each player (node and edge) present in each block a payment proportional to their contribution to the coalition.

关键词： Graph Theory Values for Graphs cooperation Games Potential Function

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The potential of starch-chitosan blends with poloxamer for the preparation of microparticles by spray-drying

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Particuology 2024年第6期89卷 1-10页

作者： Juan Enrique Barranco-García carolina caicedo Enrique Javier Jiménez-Regalado carlos Espinoza-González Graciela Morales Rocio Yaneli aguirre-Loredo Abril Fonseca-García Tecnológico Nacional de México/Instituto Tecnológico de Oaxaca Departamento de Química y BioquímicaAvenida Ing.Víctor Bravo Ahuja No.125Esquina Calzada Tecnológico68030OaxacaMexico Faculty of Engineering Unidad Central del Valle del Cauca(UCEVA)Carrera 17a 48-144763022TuluáColombia centro de Investigación en Química Aplicada(cIQA) Blvd.Enrique Reyna Hermosillo 14025294SaltilloCoahuilaMexico Investigadoras por México cONAHcYT-cIQA Av.Insurgentes Sur 1562Col.Crédito Constructor03940Alcaldía Benito JuárezCDMXMexico

Using biopolymers as wall materials in spray drying poses challenges,particularly in attaining flowability and thermal stability among their physicochemical *** paper addresses these challenges by preparing microparticles using a blend of starch–chitosan and a poloxamer,commercially named Pluronic®*** aimed to elucidate the effects of varying poloxamer concentrations on the resulting particles through the spray drying *** with a poloxamer concentration of 3%(w/v)demonstrated a notably higher yield,especially when compared to those with 0%and 1%*** with 3%and 5%(w/v)poloxamer displayed a narrower particle size distribution,with the 3%blend showing a superior yield attributed to arrangements of blend components that improve flowability.X-ray diffraction analysis showcased the characteristic peaks of A-type starch form,with shifts suggesting enhanced interactions between *** with increased poloxamer content showed elevated thermal degradation temperatures,with the 3%blend registering a significant rise,opening avenues for encapsulating heat-sensitive *** study primarily focuses on the preparation and basic characterization of *** underscores the potential of blends with optimal poloxamer concentrations in microencapsulation,emphasizing further research to harness their capabilities thoroughly.

关键词： Biopolymer Starch chitosan Pluronic®F127 Microparticles Spray drying

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一种优化开关磁阻电机换相区控制策略的高效率转矩分配函数

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电工技术学报 2024年第6期39卷 1671-1683页

作者：杨帆陈昊李晓东 Miguel Pablo aguirre Muhammad Asghar Saqib 中国矿业大学电气工程学院徐州221116 新能源电动车技术与装备中东欧国家国际联合研究中心徐州221008 江苏省高校新能源发电与电动车国际合作联合实验室徐州221008 徐州市新能源电动车技术与装备重点实验室徐州221008 澳门科技大学创新工程学院中国澳门999078 布宜诺斯艾利斯工学院电子工程系布宜诺斯艾利斯B1636 巴基斯坦工程技术大学电气工程系讷瓦布沙阿44000

转矩分配函数被广泛应用于抑制开关磁阻电机的转矩脉动。然而,输入相转矩跟踪不足或者输出相产生较大的负转矩这两种情况通常会导致电机的转矩脉动难以得到有效抑制,并降低电机的运行效率。因此,为了能够有效降低电机的转矩脉动并提高... 详细信息

转矩分配函数被广泛应用于抑制开关磁阻电机的转矩脉动。然而,输入相转矩跟踪不足或者输出相产生较大的负转矩这两种情况通常会导致电机的转矩脉动难以得到有效抑制,并降低电机的运行效率。因此,为了能够有效降低电机的转矩脉动并提高电机的效率,提出了一种新型的转矩分配函数控制策略。在提出的转矩分配函数控制策略中,电机的换相区域分为两个区域。在前一区域中,通过降低输入相转矩分配的比例,可以实现输入相实际转矩快速跟踪参考转矩,电机的转矩脉动有效降低。同时由于在输入相电感变化率较低时减少输入相分配的转矩,从而输入相的峰值电流随之降低,电机的转矩电流比提高。在后一区域中,将输出相的电流在转子对齐位置附近处减小到0,以避免产生较大的负转矩。因此,在所提出的方案下,电机的转矩脉动得到有效抑制,电机的效率也得到了提高。为了验证该方法的有效性,在一台12/8三相开关磁阻电机上进行了仿真和实验。结果表明,所提出的转矩分配函数控制策略能有效降低开关磁阻电机转矩脉动,也能有效地提高开关磁阻电机的运行效率。

关键词：开关磁阻电机转矩分配函数负转矩转矩电流比效率

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