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Journal of Forestry Research 2012年第1期23卷 39-44页

作者： angel rolando endara agramont Sergio Franco Maass Gabino Nava Bernal Juan Ignacio Valdez Hernández Todd S.Fredericksen Instituto de Ciencias Agropecuarias y Rurales(ICAR) Universidad Autónoma del Estado de MéxicoInstituto Literario N°100Col.Centro.PO.Box 50000.TolucaMéxico Colegio de Posgraduados Carretera México-TexcocoKm.36.5Montecillo.PO.Box 56230TexcocoMéxico School of Natural Sciences and Mathematics Ferrum CollegeP.O.Box 1000Ferrum VA 24088USA

Sample plots were established in the principal forest types in the the Nevado de Toluca National Park, Mexico including those domi- nated by Pinus hartwegii, Abies religiosa, Quercus laurina and Alnus jorullensis. The vertical structure was defined by three strata in the coniferous forests and two strata in the broadleaved forests. Timber harvesting in Abies religiosa and Quercus laurina forests and fires generated by humans in Pinus hartwegii forests impeded the recruitment of saplings. Mature trees were also heavily impacted by logging in Pinus hartwegii forests. On the contrary, Alnusjorullensis forests were increas- ing due to the disturbance of Pinus and Quercus forests, as well aban- doned crop lands within the park. A combination of logging, uncon- trolled fire, and grazing appears to be compromising the recruitment of important tree species in this national park. These factors, together with human settlements, have also increased the proportion of early succes- sional species. Changes in forest structure from human disturbance indicate a need to control these activities if conservation goals are not to be compromised.

关键词： forest structure human disturbance mountain forests

Analysis of Fragmentation Processes in High-Mountain Forests of the Centre of Mexico

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American Journal of Plant Sciences 2013年第3期4卷 697-704页

作者： angel rolando endara-agramont Rafael Calderón-Contreras Gabino Nava-Bernal Sergio Franco-Maass Instituto de Ciencias Agropecuarias y Rurales Toluca México Universidad Autónoma Metropolitana D. F. México México

High-mountain forests (>3500 masl) are the main supplier of environmental services to Mexico City and its metropolitan area. Taking as a study case the Nevado de Toluca National Park, this article focuses on the considerable reduction on the density of its forest cover, characterised by disturbances in the structure and dynamics of Pinus hartwegii. This specie is located towards the upper limits of the altitudinal gradient (3500 - 4100 masl) constituting the only pine species in the world capable to be established in those extreme environmental conditions. The information was collected through the implementation of 30 Sampling Plots (SP) of 20 × 50 mts (1000 m2) in three forest density categories: dense, semi-dense and fragmented. For each forest category, all trees ≥2.5 cm DBH were measured in 10 SPs. The measurement variables were DBH, total and commercial height, forest health and forest extraction. The results show the abundance of dense, semi-dense and fragmented forest (336, 202 and 150 trees/Ha-1), with extraction percentages of 11%, 20% and 33% respectively. The horizontal structure distribution shows the shape of an inverted J for the three conditions. However, the phytosanitary conditions of the semi-dense forests (83% infested trees) and fragmented (63% infested trees), do not guaranties the survival of the adult trees, implying an intensification of the fragmentation process for the next decade;given the reduction of the regeneration patterns due to the lack of healthy tree breeding.

关键词： High-Mountain Forests Fragmentation Forest Structure Forest Health

Identification of Arceuthobium globosum using unmanned aerial vehicle images in a high mountain forest of central Mexico

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Journal of Forestry Research 2020年第5期31卷 1759-1771页

作者： Luis A.Leon-Banuelos angel R.endara-agramont William Gomez-Demetrio Carlos G.Martınez-Garcıa E.Gabino Nava-Bernal 50000 TolucaMexicoMexico

The identification of forests infested by parasitic plants is important for the design of appropriate control and prevention *** images and geographic information systems are commonly used to analyze the presence of pest and parasitic plants in the *** there is a need for finer *** the last decade,the use of unmanned aerial vehicles has become increasingly common for capturing aerial images(<10 cm per pixel).The objective of the study was to obtain RGB values(Red,Green and Blue)through the colorimetric ranges for use in identification of Yellow Dwarf Mistletoe(YDM)(Arceuthobium globosum)in aerial images taken in a forest of central Mexico via a programmed *** tonalities of YDM were classified according to its phenological stages,***(young stage),yellow(adult stage),and brown(senescence stage),considering two light intensities,sunny and ***-parametric tests were used in statistical *** Spearman test showed significant negative correlation(p<0.001)between phenological stage and colour,indicating that lower RGB values were associated with greater *** differences between groups were analysed using Kruskal–Wallis(p<0.01)and Mann–Whitney tests(p<0.01).The applied algorithm identified the presence and predominant colours of YDM according to its phenological stage.

关键词： Colorimetric analysis RGB Pinus hartweggi Parasitic plants Remote sensing

Investigate the Wake Flow on Houseflies with Particle-Tracking-Velocimetry and Schlieren Photography

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Journal of Bionic Engineering 2023年第2期20卷 656-667页

作者： Yun Liu angel David Lozano Department of Mechanical and Civil Engineering Purdue University NorthwestWestvilleIN46323USA

Utilizing high-speed schlieren photography and particle-tracking-velocimetry,the wake flow of tethered houseflies is *** high-speed schlieren photography is implemented on tethered houseflies inside an air container with a stable vertical temperature gradient to visualize the disturbed wake flow from the *** resulting photography images were then processed with the physics based optical flow method to derive the light-path averaged flow ***,the state of the art:Shake-the-Box system is implemented on a tethered housefly to measure the volumetric flow field in the wake of the insect,revealing interesting flow behavior and structures that can also be observed and correlated to the schlieren photography *** the dimensionless velocity magnitude of the wake flow from the two experiments,a good qualitative agreement is reached,suggesting the viability of high-speed schlieren photography in investigating the wake flow of small ***,the high-speed schlieren photography is successfully applied on a housefly that is taking off from the ground,visualizing the disturbed wake flow on the freely flying insect that is challenging to visualize with other methods.

关键词： Insect flight Schlieren photography Shake-the-Box Wake flow

Optimal control of natural resources in mining industry

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International Journal of Mining Science and Technology 2015年第2期25卷 193-198页

作者： Petrov Nikolay Tanev angel Electrical Engineering Electronics and AutomationTechnical University-Sofia Faculty of Mathematics and Informatics Sofia University

The paper focuses on the optimal control of natural resources in mining industry. The purpose is to pro- pose an optimal extraction series of these resources during the lifetime of the Mine＇s maintenance. Fol- lowing the proposed optimal control model, a sensitivity analysis has been performed that includes the interest rate impact on the optimal solution. This study shows that the increasing of the interest rate sti- mulates faster extraction of the resources. The discounting factor induces that the resource has to be extracted faster hut this effect is counterbalanced by the diminishing returns of the annual cash flow. At higher parameters of ＂alpha＂ close to one of the power function about 80% from the whole resource will be extracted during the first 4 years of object/mine maintenance. An existence of unique positive root with respect to return of investment has been proposed and proved by two ways： by the ＂method of chords＂ and by using specialized software.

关键词： Optimal control Natural resources Interest rate Sensitivity analysis Method of chords

Habitat use and space preferences of Eurasian Bullfinches(Pyrrhula pyrrhula)in northwestern Iberia throughout the year

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Avian Research 2021年第1期12卷 37-51页

作者： angel Hernández Departamento de Ciencias Agroforestales Area de ZoologiaUniversidad de ValladolidCampus de PalenciaPalenciaEspana Instituto Universitario de Investigacion en Gestion Forestal Sostenible Universidad de ValladolidCampus de PalenciaPalenciaEspana

Background:For all vertebrates in general,a concerted effort to move beyond single season research is vital to improve our understanding of species *** of habitat use and selection by Eurasian Bullfinches(Pyrrhula pyrrhula)is limited with regard to the non-breeding *** date,research on the habitat of the Iberian subspecies iberiae consists of very general *** relation to space use,only broad features are available for the entire distribution range of Eurasian Bullfinches,including ***:In this study,seasonal preferences regarding habitat and space in a population of Eurasian Bullfinches are examined for the first time in the Iberian Peninsula,through direct observation during a six-year *** essential habitat components,substrate selection and perch height were ***:Hedgerows were the key essential habitat component for bullfinches during all ***,small poplar plantations became increasingly important from winter to *** perched mostly in shrubs/trees throughout the year,but there were significant seasonal changes in substrate use,ground and herbs being of considerable importance during *** the year,over half of the records corresponded to feeding,reaching almost 90%in ***,bullfinches perched noticeably lower while *** bullfinches perched markedly higher than females,notably singing males in *** perched at a height not much lower than that of *** all seasons,males tended to feed at greater heights than *** of different ages and sexes were seen bathing in all seasons except ***:Hedgerow habitat in general appeared to be valuable for bullfinches throughout the *** summer and autumn,they selected sites with an abundance of food and shade,as well as shelter,a much-needed requirement for fledglings and moulting *** was usually a close link between the most used

关键词： Habitat use Perch height Pyrrhula pyrrhula iberiae Seasonal variation Substrate selection Water bathing

Colorectal cancer population screening programs worldwide in 2016: An update

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World Journal of Gastroenterology 2017年第20期23卷 3632-3642页

作者： Mercedes Navarro Andrea Nicolas angel Ferrandez angel Lanas Service of Digestive Diseases University Clinic Hospital Lozano Blesa University of Zaragoza Aragón Health Research Institute (IIS Aragón) CIBERehd

Colorectal cancer(CRC)is the third most commonly diagnosed cancer in the *** incidence and mortality show wide geographical *** is recommended to reduce both incidence and ***,there are significant differences among studies in implementation strategies and *** review aimed to present the results and strategies of different screening programs *** reviewed the literature on national and international screening programs published in Pub Med,on web pages,and in clinical *** Screening programs are currently underway in most European countries,Canada,specific regions in North and South America,Asia,and *** most extensive screening strategies were based on fecal occult blood testing,and more recently,the fecal immunochemical test(FIT).Participation in screening has varied greatly among different *** Netherlands showed the highest participation rate(68.2%)and some areas of Canada showed the lowest(16%).Participation rates were highest among women and in programs that used the FIT *** exhibited the greatest number of positive *** FIT test has been the most widely used screening program *** advent of this test has increased participation rates and the detection of positive results.

关键词： Colorectal cancer Colorectal cancer screening Fecal occult blood test Fecal immunochemical test Colonoscopy

Role of gene polymorphisms in gastric cancer and its precursor lesions:Current knowledge and perspectives in Latin American countries

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World Journal of Gastroenterology 2014年第16期20卷 4503-4515页

作者： Miguel angel Chiurillo Laboratorio de Genética Molecular "Dr.Jorge Yunis-Turbay" Decanato de Ciencias de la SaludUniversidad Centroccidental Lisandro AlvaradoBarquisimeto 3001Venezuela

Latin America shows one of the highest incidence rates of gastric cancer in the world,with variations in mortality rates among nations or even within countries belonging to this *** cancer is the result of a multifactorial complex process,for which a multistep model of carcinogenesis is currently *** to the infection with Helicobacter pylori,that plays a major role,environmental factors as well as genetic susceptibility factors are significant players at different stages in the gastric cancer *** differences in population origin,demographic structure,socio-economic development,and the impact of globalization lifestyles experienced in Latin America in the last decades,all together offer opportunities for studying in this context the influence of genetic polymorphisms in the susceptibility to gastric *** aim of this article is to discuss current trends on gastric cancer in Latin American countries and to review the available published information about studies of association of gene polymorphisms involved in gastric cancer susceptibility from this region of the world.A total of 40 genes or genomic regions and69 genetic variants,58%representing markers involved in inflammatory response,have been used in a number of studies in which predominates a low number of individuals(cases and controls)*** of IL-1B(-511 C/T,14 studies;-31 T/C,10 studies)and IL-1RN(variable number of tandem repeats,17 studies)are the most represented ones in the reviewed *** genetic variants recently evaluated in large metaanalyses and associated with gastric cancer risk were also analyzed in a few studies[e.g.,prostate stem cell antigen(PSCA),CDH1,Survivin].Further and better analysis centered in gene polymorphisms linked to other covariates,epidemiological studies and the information provided by meta-analyses and genome-wide association studies should help to improve our understanding of gastric cancer etiology in order to d

关键词： Latin America Gastric cancer Precancerous lesions Gene polymorphisms Single nucleotide polymorphisms

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Chinese Annals of Mathematics,Series B 2009年第5期30卷 505-512页

作者： angel CASTRO Diego CóRDOBA Instituto de Ciencias Matemticas CSIC-UAM-UC3M-UCMConsejo Superior de Investigaciones Científicas

The authors construct self-similar solutions for an N-dimensional transport equation,where the velocity is given by the Riezs *** solutions imply nonuniqueness of weak *** addition,self-similar solution for a one-dime... 详细信息

关键词： Hilbert transform Riesz transform Transport equations Self-similar solutions

Software Project Effort Estimation Based on Multiple Parametric Models Generated Through Data Clustering

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Journal of Computer Science & Technology 2007年第3期22卷 371-378页

作者： Juan J.Cuadrado Gallego Daniel Rodríguez Miguel angel Sicilia Miguel Garre Rubio angel García Crespo Department of Computer Science The University of Alcalá AlcaláSpain Department of Computer Science Carlos Ⅲ University.Madrid Spain

Parametric software effort estimation models usually consists of only a single mathematical relationship. With the advent of software repositories containing data from heterogeneous projects, these types of models suffer from poor adjustment and predictive accuracy. One possible way to alleviate this problem is the use of a set of mathematical equations obtained through dividing of the historical project datasets according to different parameters into subdatasets called partitions. In turn, partitions are divided into clusters that serve as a tool for more accurate models. In this paper, we describe the process, tool and results of such approach through a case study using a publicly available repository, ISBSG. Results suggest the adequacy of the technique as an extension of existing single-expression models without making the estimation process much more complex that uses a single estimation model. A tool to support the process is also presented. Keywords software engineering, software measurement, effort estimation, clustering

关键词： software engineering software measurement effort estimation clustering