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Spatiotemporal patterns of burned areas,fire drivers,and fire probability across the equatorial Andes

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Journal of Mountain Science 2021年第4期18卷 952-972页

作者： Xavier ZAPATA-RiOS Carmen LOPEZ-FABARA Abigail NAVARRETE Sandra TORRES-PAGUAY Miguel flores Department of Civil and Environmental Engineering Escuela Politecnica NacionalLadron de Guevara E11-253P.O.Box 17-01-2759QuitoEcuador Center for Research and Water Resources Studies(CIERHI) Escuela Politecnica NacionalLadron de Guevara E11-253P.O.Box 17-01-2759QuitoEcuador Faculty of Agricultural Sciences Universidad Central del EcuadorAv.UniversitariaP.O.Box 17-03-100QuitoEcuador Modeling Optimization and Inferential Statistics Group(MODES)Department of MathematicsEscuela Politecnica NacionalLadron de Guevara Ell-253P.O.Box 17-01-2759QuitoEcuador

Field-based fire studies in the equatorial Andes indicate that fires are strongly associated with biophysical and anthropogenic ***,fire controls and fire regimes at the regional scale remain ***,this paper describes spatial and temporal burned-area patterns,identifies biophysical and anthropogenic fire drivers,and quantifies fire probability across 6°of latitude and 3°of longitude in the equatorial *** spatial and temporal burned-area analysis was carried out based on 18 years(2001-2018)of the MCD64 A1 MODIS burned-area ***,topography,vegetation,and anthropogenic variables were integrated in a logistic regression model to identify the significance of explanatory variables and determine fire occurrence probability.A total of 5779 fire events were registered during the 18 years of this study,located primarily along the western cordillera of the Andes and spreading from North to ***-eight percent of these fires took place within two fire hotspots located in the northwestern and southwestern corners of the study ***-nine percent occurred during the second part of the year,between June and *** largest density of fires was primarily located on herbaceous vegetation and *** show that mean monthly temperature,precipitation and NDVI during the prefire season,the location of land cover classes such as forest and agriculture,distance to roads and urban areas,slope,and aspect were the most important determinants of spatial and temporal fire *** logistic regression model achieved a good accuracy in predicting fire probability(80%).Probability was higher in the southwestern and northern corners of the study area,and lower towards the north in the western and eastern piedmonts of the *** analysis contributes to the understanding of fires in mountains within the *** results here presented have the potential to contribute to fire management and control in the regi

关键词： MODIS MCD64A1 Spectral vegetation indices Pre-fire season NDVI and precipitation Remote sensing

Remediation of amide pesticide-polluted soils by combined solarization and ozonation treatment

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Pedosphere 2024年第3期34卷 641-651页

作者： Isabel GARRIDO Carmen MMARTINEZ Pilar flores Pilar HELLIN Fulgencio CONTRERAS Jose FENOLL Department of Sustainability and Quality Group of Fruit and Vegetable Products Instituto Murciano de Investigacion y Desarrollo Agrario y MedioambientalLa Alberca 30150(Spain)

Agriculture has a close relationship with nature,but it can also be the source of negative and permanent environmental *** use of pesticides in modern agriculture is a common practice,but their side effects on the environment cannot be *** this study,we evaluated a combination of solarization and ozonation techniques for the elimination of six amide pesticides(boscalid,chlorantraniliprole,cyflufenamid,fluopyram,napropamide,and propyzamide)in *** experiments were performed with four different soils to assess the efficiency of this methodology at different soil temperatures and ozone dosages under laboratory conditions,and then a greenhouse pot experiment was conducted under controlled conditions during *** days after the onset of the experiments,higher degradation percentages of amide pesticides were observed in ozonized soils than in other treated soils,particularly when ozone was applied at 10 cm soil *** results show that the utilization of ozonation,along with solarization,represents a valid method for degrading residues of the studied pesticides and suggest that this combined technology may be a promising tool for remediating pesticide-polluted soils.

关键词： intermediate ozone pesticide degradation pesticide residue polyethylene film remediation technique

A technical and socioeconomic approach to estimate forest residues as a feedstock for bioenergy in northern Mexico

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Forest Ecosystems 2019年第4期6卷 312-322页

作者： Guadalupe Carrasco-Diaz Gustavo Perez-Verdin Jonathan Escobar-flores Marco Antonio Marquez-Linares Instituto Politecnico Nacional CIIDIR Dgo.

Background: Forest residues can be a feasible alternative for converting energy into fuels, electricity, or *** to other second-generation bioenergy sources, they do not compete for food, are relatively cheap,abundant in forest-rich areas, and more importantly their energy balance is close to zero. Biomass estimations can help design energy strategies to reduce fossil fuels dependency. Because of the land property distribution in Mexico,biomass estimations should consider not only the physical availability, but also the willingness of landowners to extract such raw ***: This study presents a methodological approach for evaluating the potential use of forest residues as a feedstock to generate bioenergy in northern Mexico. Remote sensing and field forest inventory were used to estimate the quantity and distribution of forest residues. In addition, a discrete choice analysis evaluated landowners’ preferences towards bioenergy development, including the most important factors that influence their willingness to extract their products and the expected *** and conclusions: Considering both physical and socio-economic aspects, results showed that about59,000 metric tons per year could be available in the study area. The vast majority of landowners surveyed are willing to extract forest residues, as long as they are presented with extraction plans with the highest income. However, many showed concerns about the environmental impacts this activity can have on soils,plants, and fauna. These results can help evaluate the potential of these resources for bioenergy development.

关键词： Bioenergy Choice experiments Forest landowners Forest residues Remote sensing

Characterization of Cd1-xZnxTe（0≤x≤1） Nanolayers Grown by Atomic Layer Deposition on GaSb and GaAs（001） Oriented Substrates

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Journal of Electronic Science and Technology 2019年第2期17卷 97-108页

作者： Joel Díaz-Reyes Roberto Saúl Castillo-Ojeda José Eladio flores-Mena Center for Research in Applied Biotechnology Instituto Politécnico Nacional Tepetitla 90700 Mexico Universidad Politécnica de Pachuca Pachuca 43830 Mexico Faculty of Sciences of the Electronics Autonomous University of Puebla Puebla 72570 Mexico

ZnTe, CdTe, and the ternary alloy CdZnTe are important semiconductor materials used widely for the detection of an important range of electromagnetic radiation as gamma ray and X-ray. Although, recently these materials have acquired renewed importance due to the new explored nanolayer properties of modern devices. In addition, as shown in this work they can be grown using uncomplicated synthesis techniques based on the deposition in vapour phase of the elemental precursors. This work presents the results obtained from the deposition of nanolayers of these materials using the precursor vapour on GaAs and GaSb (001) substrates. This growth technique, extensively known as atomic layer deposition (ALD), allows the layers growth with nanometric dimension. The main results presented in this work are the used growth parameters and the results of the structural characterization of the layers by the means of Raman spectroscopy measurements. Raman scattering shows the peak corresponding to longitudinal optical (LO)-ZnTe, which is weak and slightly redshift in comparison with that reported for the ZnTe bulk at 210 cm^-1. For the case of the CdTe nanolayer, Raman spectra presented the LO-CdTe peak, which is indicative of the successful growth of the layer. Its weak and slightly redshift in comparison with that reported for the CdTe bulk can be related with the nanometric characteristic of this layer. The performed high-resolution X-ray diffraction (HR-XRD) measurement allows to study some important characteristics such as the crystallinity of the grown layer. In addition, the HR-XRD measurement suggests that the crystalline quality has dependence on the growth temperature.

关键词： Ⅲ-Ⅴ substrates atomic layer deposition(ALD) defect generation mechanism ternary alloy Cd1-xZnxTe Zn and Cd mixture

Shade shelters increase survival and photosynthetic performance of oak transplants at abandoned fields in semi-arid climates

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Journal of Forestry Research 2013年第1期24卷 23-28页

作者： Claudia González-Salvatierra Ernesto Iván Badano Joel flores Juan Pablo Rodas División de Ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaA.C.Camino a la Presa San José 2055C.P. 78216San Luis PotosíS.L.P.México.

Forest restorations conducted in semiarid, seasonally dry climates must deal with the intense drought stress that affects tree seedlings during the dry season. Although this water deficit is the most commonly invoked source of mortality for seedlings, several other environmental factors may also preclude survival of transplants. For instance, it has been widely reported that excessive light reduces the efficiency of the photosynthetic apparatus, hence decreasing plant survival, but most seedling transplants in deforested areas are conducted under these light conditions. This study is focused in determining whether excessive light affects the photosynthetic performance and survival of Quercus coccolobifolia, a Mexican oak species, when their seedlings are transplanted in semiarid deforested areas. Further, this study tests the possibility of using artificial shade shelters to improve the ecophysiological performance and survival of seedlings. Oak seedlings were transplanted under full sunlight conditions and beneath artificial shade shelters of two different colors： white and black. To reduce water stress, and hence isolate the effects of light treatments, a drip irrigation system was implemented at each experimental plot. Seedling survival was monitored weekly for 128 days and photosynthetic performance was assessed by measuring chlorophyll fluorescence at three opportunities during the experiment. Sun-exposed seedlings showed lower photosynthetic performance and survival rates than those beneath shelters of both colors. These results suggest that sunlight damage can reduce seedling survival when they are transplanted in exposed sites, and that shade shelters can improve the success of forest restoration programs in semiarid climates.

关键词： chlorophyll fluorescence light stress photoinhibition reforestation forest restoration

Resveratrol effects on neural connectivity during aging

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Neural Regeneration Research 2016年第7期11卷 1067-1068页

作者： Gonzalo flores Rubén Antonio Vázquez-Roque Alfonso Diaz Instituto de fisiología Benemerita Universidad autónoma de Puebla.14 Sur 6301PueblaMexico Departamento de Farmacia Facultad de Ciencias químicasbenemérita Universidad autónoma de PueblaPueblaMexico

Aging has been considered a natural process of any living *** rate of aging depends on many factors,including genetic and environmental *** this reason,many researchers in this field suggest that aging is an epigeneti... 详细信息

关键词： resveratrol connectivity older hippocampus neuronal metabolism cortical Aging cortex PPAR

Laparoscopic Trainer with Pneumoperitoneum

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Surgical Science 2012年第10期3卷 499-502页

作者： José L. ortiz Simón Arturo Minor Martínez Neftalí Prado Coronado Ricardo Ordorica flores Bioelectronics Section Center for Research and Advanced Studies of the IPN México DF México Department of Electrical and Electronics Engineering Technological Institute of Nuevo Laredo Nuevo Laredo México Pediatrics Section Federico Gómez Children’s Hospital México DF México

The development of skills and abilities in laparoscopy is directly related to the use of trainers. The trainer should model the patient with all its natural complexities as closely as possible. In this article we propose a system for training the establishment of pneumoperitoneum executing the basic tasks to create the workspace in the trainer, the insertion of primary umbilical trocar and simulate some of the everyday problems in surgery. Materials and Methods. A group of electrical with biomedical engineers and laparoscopic surgeons developed a physical trainer that allows implementing the pneumoperitoneum. The system uses pneumatic electro valves that are controlled with a dedicated microprocessor. The user can program the system to set the parameters of the pneumoperitoneum. Results. This new trainer facilitated the programming of right values of parameters to distend the abdominal cavity according a specific clinical case. The model developed enables the trainee to consolidate his knowledge on establishing the parameters required within clinical practice, as well as the entry techniques. Conclusions. A new physical model for laparoscopic training was designed. The system enables the laparoscopic surgeon to set the parameters for establishing the workspace according to the clinical case. The trainer allows the surgeon to train in the Hasson technique for the introduction of the first trocar, as well as the placement of the rest of surgical instruments with video assistance. We think this new trainer system will help minimize entry-related injuries.

关键词： Laparoscopy Trainer Pneumoperitoneum

A Numerical Study Comparing the Effect on Residual Stresses of Two Different Types of Projectiles During Shot Peening

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Computers, Materials & Continua 2016年第3期51卷 203-215页

作者： J.Solórzano-López F.A.García-Pastor Angélica flores-Luna UNAM Facultad de QuímicaCiudad de MéxicoMéxico Cinvestav Unidad Saltillo CoahuilaMéxico TecNM Instituto Tecnológico de Tláhuac IIICiudad de MéxicoMéxico

Shot peening is a widely used technique to improve fatigue life in metallic *** processing technique introduces a subsurface compressive residual stress field through a plastic deformation of the surface caused by the impact of a large number of high-speed *** are a number of parameters that affect the residual stress field depth and *** effects of the impact angle,shot speed and shot geometry are currently being *** particular,substituting spherical cast shots by cylindrical cut wire shots is an attractive option,especially in terms of *** effect of shot geometry on residual stresses,however,needs to be further *** industrial-scale experimentation is costly and cumbersome,mathematical modeling offers a convenient alternative to carry out this type of *** present work shows a comparison between the residual stresses generated by the impact of spherical and cylindrical projectiles on a steel *** threedimensional model was developed using ABAQUS finite element commercial software(Release 6.12,Dassault Systémes,France).The results show that cylindrical shots generate residual stress fields t hat a re higher in magnitude than t hose generated by a spherical ***,the residual stress field of cylindrical shots impacting the surface at an oblique angle shows an important degree of *** effect is not found when spherical shots impact the surface at the same oblique angle.

关键词： Shot Peening Finite element method Residual Stresses

Siglec genes confer resistance to systemic lupus erythematosus in humans and mice

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Cellular & Molecular Immunology 2019年第2期16卷 154-164页

作者： Rhonda flores Peng Zhang Wei Wu Xu Wang Peiying Ye Pan Zheng Yang Liu Center for Cancer and Immunology Research Children’s National Medical CenterWashingtonDC 20010USA

A recent meta-analysis revealed the contribution of the SIGLEC6 locus to the risk of developing systemic lupus erythematosus(SLE).However,no specific Siglec(sialic acid-binding immunoglobulin-like lectin)genes(Siglecs)have been implicated in the pathogenesis of ***,we performed in silico analysis of the function of three major protective alleles in the locus and found that these alleles were expression quantitative trait loci that enhanced expression of the adjacent SIGLEC12 *** data suggest that SIGLEC12 may protect against the development of SLE in Asian *** with human genetic data,we identified two missense mutations in lupus-prone ***1/Sle2/Sle3(Sle1–3)mice in Siglece,which is the murine Siglec with the greatest homology to human *** the mutations resulted in reduced binding of Siglec E to splenic cells,we evaluated whether Siglece−/−mice had SLE *** found that Siglece−/−mice showed increased autoantibody production,glomerular immune complex deposition and severe renal pathology reminiscent of human SLE *** data demonstrate that the Siglec genes confer resistance to SLE in mice and humans.

关键词： Siglecs CD24 HMGB1 systemic lupus erythematosus