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National assessment of the fragmentation,accessibility and anthropogenic pressure on the forests in Mexico

Journal of forestry Research 2012年第4期23卷 529-541页

作者： rafael Moreno-Sanchez Juan Manuel Torres-Rojo francisco Moreno-Sanchez Sue Hawkins Justin Little Susan McPartland University of Colorado Denver Department of Geography and Environmental SciencesCampus Box 172 P.O.Box 173364DenverCO 80217-3364USA. Centro de Investigación y Docencia Económicas(CIDE) Carretera México-Toluca 3655Col.Lomas de Santa FeMéxicoD.F.01210México. Instituto Nacional de Investigaciones forestales y Agropecuarias(INIfAP) Av Progreso #5CoyoacánMéxico D.F.04100México Department of Geography and Environmental Sciences University of Colorado DenverCampus Box 172 P.O.Box 173364 DenverCO 80217-3364USA

forest managers and policy makers increasingly demand to have access to estimates of forest fragmentation, human accessibility to forest areas and levels of anthropogenic pressure on the remaining forests to integrate them into monitoring systems, management and conservation plans. forest fragmentation is defined as the breaking up of a forest unit, where the number of patches and the amount of expose edge increase while the amount of core area decreases. forest fragmentation studies in Mexico have been limited to local or regional levels and have concen- trated only on specific forest types. This paper presents an assessment of the fragmentation of all forest types at the national level, their effective proximity to anthropogenic influences, and the development of an indica- tor of anthropogenic pressure on the forests areas. Broadleaf forests, tropical evergreen forests and tropical dry deciduous forests show the greatest fragmentation. Almost half （47%） of the tropical forests are in close effective proximity to anthropogenic influences and only 12% of their area can be considered isolated from anthropogenic influences. The values for the temperate forests are 23% and 29% respectively. Anthro- pogenic pressure in the immediate vicinity of anthropogenic activities is much higher in the tropical forests （75 in a scale 0-100） than in the tem- perate forests （30）. When considering these results jointly, the tropical forests, and more specifically, the tropical evergreen forests and tropical dry deciduous forests are under the greatest pressure and risks of degra- dation.

关键词： forest fragmentation effective proximity anthropogenicpressure Mexico forests GIS.

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A modified Genetic algorithm suitable for non stationary functions.

A modified Genetic algorithm suitable for non stationary fun...

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The fourth World Congress of Structural and Multidisciplinary Optimization

＜正＞The work presented in this article is structured in three parts, focusing its attention on the reduction of the execution time required by the GA to accomplish the evolutive process when the error function is very complex. In order to do it, several strategies will be presented and studied. In the first one, a theoretical approach to determine optimal population size and the construction of an approximated and stepped evaluation function is presented. In the second one OMEGA （Oriented to Mechanical Engineering Genetic Algorithm） is presented, a modified GA which includes the use of models with different degrees of complexity and a dynamic mutation operator whose purpose is to substantially reduce the number of evaluations of the complete error function. This program has been developed based on David Levine’ s PGAPack library /26/. In the third part of the work, results obtained by OMEGA in a practical optimisation problem （an error function used in the synthesis of multibody systems /1/, /2/, /3/, /4/, /5/） will be presented.

关键词： Genetic Algorithms Numerical Optimisation Non Stationary Mediums Variable Complexity functions Adaptive Mutation.

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Nano-fried-eggs： Structural, optical, and magnetic characterization of physically prepared iron-silver nanoparticles

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Nano Research 2018年第11期11卷 6074-6085页

作者： Julien Ramade Nicolas Troc Olivier Boisron Michel Pellarin Marie-Ange Lebault Emmanuel Cottancin Vitor T. A. Oiko rafael Cabreira Gomes Varlei Rodrigues Matthias Hillenkamp Univ. Lyon Universitd Claude Bernard Lyon I CNRS UMR5306 Institut Lumiee Matiee t=-69622 Villeurbanne France Instituto de f[sica Gleb Wataghin UNICAMP CP 6165 13083-970 Campinas SP Brazil

The prospect of combining both magnetic and plasmonic properties in a single nanoparticle promises both valuable insights on the properties of such systems from a fundamental viewpoint and numerous possibilities for technological applications. However, the combination of two of the most prominent metallic candidates—iron and silver—has presented numerous experimental difficulties because their thermodynamic properties impede miscibility and even coalescence. Herein, we present the thorough characterization of physically prepared fe50Ag50 nanoparticles embedded in carbon and silica matrices via electron microscopy, optical spectroscopy, magnetometry and synchrotron-based X-ray spectroscopy. Iron and silver segregate completely into structures resembling fried eggs, with a nearly spherical, crystallized silver part surrounded by an amorphous structure of iron carbide or oxide, depending on the environment of the particles. Consequently, the particles exhibit both plasmonic absorption corresponding to the silver nanospheres in an oxide environment and a reduced but measurable magnetic response. The suitability of such nanoparticles for technological applications is discussed from the viewpoint of their high chemical reactivity with their environment.

关键词： nanoalloy bimetallic nanoparticles iron silver feAg optical spectroscopy magnetometry

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Thermomechanical Behavior and Corrosion Resistance of a 316 L Austenitic Stainless Steel

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Materials Sciences and Applications 2020年第4期11卷 217-233页

作者： rafael P. ferreira Carmem C. f. Nascimento Gedeon S. Reis Eden S. Silva Samuel f. Rodrigues Graduate Program in Materials Engineering Federal Institute of Education Science and Technology of Maranhao (IFMA) Sao Luis Brazil

Hot-formed components are constantly exposed to hostile environments with corrosive substances. Microstructural changes caused by thermomechanical processing can be predicted to increase the corrosion resistance of austenitic stainless steels. The objective of this study is to understand the relationship between the dynamic softening mechanisms and corrosion resistance, thus optimizing the hot-forming process. In the current work, the dynamic recrystallization (DRX) behavior of AISI 316 L austenitic stainless steel was studied in the temperature range of 1273 - 1423 K and strain-rate range of 0.1 - 5.0 s-1 using physical simulation. Subsequently, potentiodynamic polarization tests and scanning electron microscopy were performed on the hot-deformed samples to investigate the influence of temperature and strain-rate on the corrosion resistance and mechanical properties. The results indicated that the DRX fractions increased under low-temperature and high strain-rate conditions, resulting in grain refinement. The potentiodynamic polarization tests indicated that the dynamically recovered samples demonstrated high resistance to corrosion compared with the DRX samples. The best route found for the investigated alloy was for the strain to be applied at a temperature of 1423 K and a strain rate of 0.1 s-1.

关键词： 316 L Austenitic Stainless Steel Softening Phenomena Corrosion

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Intracerebral Microdialysis in Neurosurgery for Obsessive-Compulsive Disorder: Report of 2 Preliminary Cases

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Open Journal of Modern Neurosurgery 2020年第3期10卷 371-381页

作者： Sergio A. Sacchettoni rafael Galera Juan f. Del Corral Juan P. Abud Aníbal Pinero Luis Teneud Napoleón Torres rafael Rojas Pedro Rada félix Guerrero Edgar González Mónica Bifano Dely Yazawa Luis Hernández Hospital and School of Medicine JM Vargas Universidad Central de Venezuela Caracas Venezuela Centro Medico-Docente La Trinidad Caracas Venezuela Neurology Mobile System Associates Miami FL USA Laboratory of Physiology of Behavior Universidad de Los Andes Mérida Venezuela University of Grenoble-Alpes CEA LETI Clinatec France

Neurosurgery for psychiatric disorders, notably for obsessive-compulsive disorder (OCD), was initiated in Venezuela in the decade of 1970, and consisted since that time in the classic stereotactic anterior cingulotomy. In order to know further about the physiopathology of this disorder, we performed intracerebral microdialysis in 2 patients who were operated on. The aim was to measure changes in extracellular neurotransmitters within the basal ganglia. The microdialysis probes were stereotactically placed in the right caudate nucleus and in the dorsomedial nucleus of the right thalamus. The microdialysis was done before the left cingulotomy, during the pause and after the right cingulotomy. Glutamate and gamma-aminobutyric acid (GABA) changes were similar in the caudate nucleus of both patients, whereas in the dorsomedial nucleus the changes were opposite among the 2 patients. Although this study does not bring enough data to explain such differences yet, the existence of dynamic changes in the neurochemistry of the basal ganglia during cingulotomy shows that intracerebral microdialysis can help in the understanding of the pathophysiology of OCD and eventually in the design of new surgeries with better results.

关键词： Psychiatric Neurosurgery Psychosurgery Obsessive-Compulsive Disorder Intracerebral Microdialysis

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Six steps for building a technological knowledge base for future taxonomic work

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National Science Review 2022年第12期9卷 19-21页

作者： Michael C.Orr Anderson feijó Douglas Chesters Alfried P.Vogler Silas Bossert rafael R.ferrari Mark John Costello Alice C.Hughes Lars Krogmann John S.Ascher Xin Zhou De-Zhu Li Ming Bai Jun Chen Deyan Ge Arong Luo Gexia Qiao Paul H.Williams Ai-bing Zhang Keping Ma feng Zhang Chao-Dong Zhu Key Laboratory of Zoological Systematics and Evolution Institute of Zoology Chinese Academy of Sciences Entomologie Staatliches Museum für Naturkunde Stuttgart Department of Life Sciences Silwood Park Campus Imperial College London Natural History Museum Department of Entomology Washington State University Department of Entomology National Museum of Natural History Smithsonian Institution faculty of Biosciences and Aquaculture Nord University School of Biological Sciences University of Hong Kong Department of Biological Sciences National University of Singapore Department of Entomology China Agricultural University Germplasm Bank of Wild Species Kunming Institute of Botany Chinese Academy of Sciences College of Life Sciences Capital Normal University Institute of Botany Chinese Academy of Sciences Department of Entomology College of Plant Protection Nanjing Agricultural University State Key Laboratory of Integrated Pest Management Institute of Zoology Chinese Academy of Sciences College of Life Sciences University of Chinese Academy of Sciences

Species are the principal category we use to study,understand,and conserve the natural world,so how we define species has a cascading impact across fields,well beyond biology [1].Despite such importance,debate on species concepts continues to this day ([2] 2020),with consequences for what organisms we recognize,study and *** the wealth of life forms on our planet,

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In vivo assessment of intratumoral aspirin injection to treat hepatic tumors

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World Journal of Hepatology 2013年第7期5卷 372-378页

作者： Rogério Saad-Hossne fábio Vieira Teixeira rafael Denadai Division of Coloproctology Department of Surgery Botucatu Medical School University of the State of So Paulo

AIM: To study the antineoplastic efficacy of 10% aspirin intralesional injection on VX2 hepatic tumors in a rabbit model. METHODS: Thirty-two male rabbits (age: 6-9 wk; body weight: 1700-2500 g) were inoculated with VX2 hepatic tumor cells (104 cells/rabbit) via supraumbilical median laparotomy. On day 4 post-implantation, when the tumors were about 1 cm in diameter, the rabbits were randomly divided into the following groups (n = 8 each group) to assess early (24 h) and late (7 d) antineoplastic effects of intratumoral injection of 10% bicarbonate aspirin solution (experimental groups) in comparison to intratumoral injection of physiological saline solution (control groups): group 1, 24 h control; group 2, 24 h experimental; group 3, 7 d control; group 4, 7 d experimental. The serum biochemistry profile (measurements of glycemia, alkaline phosphatase, gamma-glutamyl transferase, aspartateaminotransferase, and alanine aminotransferase) and body weight measurements were obtained for all animals at the following time points: D0, before tumor implant; D4, day of treatment; D5, day of sacrifice for groups 1 and 2; D11, day of sacrifice for groups 3 and 4. Gross assessments of the abdominal and thoracic cavities were carried out upon sacrifice. The resected liver tissues, including hepatic tumors, were qualitatively (general morphology, signs of necrosis) and quantitatively (tumor area) assessed by histopathological analysis. RESULTS: Gross examination showed no alterations, besides the left hepatic lobe tumors, had occurred in the thoracic and abdominal cavities of any animal at any time point evaluated. However, the features of the tumor foci were distinctive between the groups. Compared to the control groups, which showed normal unabated tumor progression, the aspirin-treated groups showed imprecise but limited tumor boundaries and a general red-white coloration (indicating hemorrhaging) at 24 h post-treatment, and development of yellow-white areas of a cicatricial as

关键词： Intralesional injection Intratumoral injection Aspirin Hepatic tumor VX2 Rabbit Antineoplastic Therapy

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Snai-1 and Epithelial-Mesenchymal Transition-Related Protein Immunoexpression in Canine Mammary Carcinomas

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Advances in Breast Cancer Research 2014年第4期3卷 111-117页

作者： Breno S.Salgado rafael M.Rocha fernando A.Soares fátima Gartner Noeme S.Rocha Departamento de Patologia Faculdade de Medicina de BotucatuUniversidade Estadual Paulista(UNESP)BotucatuBrazil Laboratório de Patologia Investigativa e Comparada Departamento de Clínica VeterináriaFaculdade de Medicina Veterinária e ZootecniaUniversidade Estadual Paulista(UNESP)BotucatuBrazil Departamento de Anatomia Patológica Hospital A.C.CamargoFundacao Antonio PrudenteSao PauloBrazil Institute of Pathology and Molecular Immunology(IPATIMUP) OportoPortugal

Epithelial-mesenchymal transition (EMT) is defined as switching of polarized epithelial cells to a migratory fibroblastoid phenotype. EMT is known to be involved in the progression and metastasis of various cancers in humans, but this specific process is still little explored in the veterinary literature. The aim of this research was to evaluate the expression of EMT-related proteins in canine mammary carcinomas (CMCs). The expression of six EMT-related proteins in 94 CMCs of female dogs was evaluated by immunohistochemistry using a tissue array method. Additionally, clinicopathological characteristics were compared with the expression of EMT-related proteins. Loss of epithelial protein and/or acquisition of the expression of mesenchymal proteins were observed in CMCs. Loss of epithelial protein and/or acquisition of the expression of mesenchymal proteins were observed, particularly in tumors with evidence of stromal invasion;however, significance was only observed between the S100A4 and vascular invasion. In addition, Snai-1 nuclear immunoexpression was significantly related to E-cadherin loss. In conclusion, loss of epithelial proteins and/or the acquisition of mesenchymal proteins are associated with EMT and may have an important role in the evaluation of CMC patients. The unique immunoexpression pattern of Snai-1 could help to distinguish between an adenoma and a non-metastatic carcinoma and seems to be related to conversion of myoepithelial cells to a complete mesenchymal-like phenotype. Loss of E-cadherin and cytokeratin and change of immunoexpression pattern of Snai-1, N-cadherin, S100A4 and MMP-2 indicate the occurrence of EMT in canine mammary carcinomas and should result in an en bloc resection or a close follow-up.

关键词： EMT S100A4 Keratin Mammary Tumors Dog

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Studying Group Dynamics through Social Networks Analysis in a Medical Community

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Social Networking 2014年第2期3卷 134-141页

作者： Ruben P. Albuquerque Jonice Oliveira fabrício f. faria rafael Monclar Jano M. de Souza Graduate School in Computing Science (PPGI) Universidade Federal do Rio de Janeiro (UFRJ) Rio de Janeiro Brasil Systems and Computing Engineering Graduate School (COPPE) Universidade Federal do Rio de Janeiro (UFRJ) Rio de Janeiro Brasil Systems and Computing Engineering Graduate School (COPPE) Universidade Federal do Rio de Janeiro (UFRJ)Rio de Janeiro Brasil

In 2008, the Brazilian Department of Science and Technology created the INCTs (Brazilian Science and Technology Institutes). One of them was the Cancer Control INCT. Due to its importance and considering that there are different groups working together in the same area, it is important that they collaborate intensely. Envisioning an empowerment of scientific collaboration, the BRINCA project was created to support a set of analyses of the social networks from this particular INCT. These analyses were created by mining curricular and publications bases, and identifying different types of scientific relationships and areas. We were able to observe, for instance, how the interaction is amongst researchers from related areas, which researchers were more collaborative and which ones were isolated from the network. These analyzes were used by the INCT coordination to understand and act to improve scientific collaboration.

关键词： Social Networks Scientific Collaborations Data Mining

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Seasonal variation in native hydraulic conductivity between two deciduous oak species

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Journal of Plant Ecology 2020年第1期13卷 78-86页

作者： Dilia Mota-Gutiérrez Guadalupe Arreola-González rafael Aguilar-Romero Horacio Paz Jeannine Cavender-Bares Ken Oyama Antonio Gonzalez-Rodriguez fernando Pineda-García facultad de Biología Universidad Michoacana de San Nicolás de Hidalgo.Edificio RCiudad UniversitariaGral.Francisco J.Múgica S/N A-1Felicitas de Río58030 MoreliaMichoacánMexico Escuela Nacional de Estudios Superiores Unidad MoreliaUniversidad Nacional Autónoma de México.Antigua Carretera a Pátzcuaro 8701Ex-Hacienda de San Joséde La Huerta58190 MoreliaMichoacánMexico Instituto de Investigaciones en Ecosistemas y Sustentabilidad Campus MoreliaUniversidad Nacional Autónoma de México.Antigua Carretera a Pátzcuaro 8701Ex-Hacienda de San Joséde La Huerta58190 MoreliaMichoacánMexico Deparment of Ecology Evolution and BehaviorUniversity of MinnesotaSaint PaulMN 55108USA

植物抗旱性机制包括耐旱性和避旱性。耐旱性的特征主要是木质部易栓塞性和膨压损失点,而避旱性的特征则是叶片脱落和落叶性。虽然这些机制可以权衡物种连续性,但对于干旱引发的叶片脱落和持续时间的变化如何影响木质部和叶片耐受性之间... 详细信息

植物抗旱性机制包括耐旱性和避旱性。耐旱性的特征主要是木质部易栓塞性和膨压损失点,而避旱性的特征则是叶片脱落和落叶性。虽然这些机制可以权衡物种连续性,但对于干旱引发的叶片脱落和持续时间的变化如何影响木质部和叶片耐受性之间的关系却知之甚少。在本研究中,我们研究两种具有不同叶片脱落叶行为的橡树(栎属)的耐旱性程度差异。我们预测了Quercusdeserticola在旱季结束时落叶(晚落叶)而面临更大的空化风险,导致其比***更耐旱,对水分的利用也更加保守。***只在旱季中期很短的时间内落叶(短落叶)。本研究在墨西哥中部进行,两种橡树各具有单个种群,它们之间相距1.58公里,海拔差为191米。***(晚落叶)多出现在下坡,而***(短落叶)多出现在沿坡度海拔较高的地方。我们评估了样地内茎干的水分传导率的季节差异(雨季和旱季),并检测了两个物种间木质部对空化的脆弱性、叶片水分利用和叶片膨松损失点的差异。两种橡树在耐旱性状方面没有显著差异,主要包括木质部易栓塞性、叶片膨松损失点和气孔导度。然而,两种植物在旱季都有不同的表现:短落叶植物对木质部功能的负面影响要比晚落叶植物低。综上所述,两种橡树在植物生理性能方面的季节变化取决于冠层叶面积的减少。

关键词：栎属树木水力传导栓塞叶片物候学

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