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Reconstruction of debris-flow activity in a temperate mountain forest catchment of central Mexico

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Journal of Mountain Science 2019年第9期16卷 2096-2109页

作者： Osvaldo franco-RAMOS Markus STOFFEL juan Antonio BALLESTEROS-CANOVAS Instituto de Geografia. Universidad NacionalAutonoma de Mexico Ciudad Universitaria Coyoacan 04510 Mexico Dendrolab.ch Department of Earth Sciences University of Geneva 13 rue des Maraichers CH-1205 Geneva Switzerland Climate Change Impacts and Risks in the Anthropocene (C-CIA) Institute for Environmental Sciences University of Geneva 66 Boulevard Carl-Vogt CH-1205 Geneva Switzerland Department F.-A. Forelfor Environmental and Aquatic Sciences University of Geneva 66 Boulevard Carl-Vogt CH- 1205 Geneva Switzerland

The use of dendrochronology to study and date geomorphic processes in volcanic environments is still incipient, even more so on the volcanic slopes covered by temperate forests in central Mexico. Mass movements, such as debris flows, often impact forest stands where they cause damage to individual trees, thereby generating growth disturbances(GD) in the tree-ring records. The identification and dating of GD enables reconstruction of the age of trees colonizing bare surfaces after major events, but also allows the assessment of the frequency or spatial distribution of past geomorphic process activity. Here we used increment cores from 65 Pinus leiophylla, Abies religiosa, and Alnus jorullensis trees growing in the Axal gorge, on the southern slopes of La Malinche volcano, to unravel past debris-flow activity both temporally and spatially. Based on the combination of GD records, a weighted tree response index(Wit), field evidence and hydrometeorological records, we reconstructed 23 debris flows since ***, almost two-thirds of the reconstructed years with debris-flow activity in Axal gorge match with events recorded in Axaltzintle gorge located on the NE slopes of La Malinche. These findings suggest a regional triggering mechanism, most likely related to the occurrence of hurricanes. This research could be useful for disaster risk management of the La Malinche National Park.

关键词： Debris flows La Malinche volcano Dendrogeomorphology Temperate forest Hydrometeorological phenomena

SYNTHESIS AND PROPERTIES OF HOMOPOLYMER AND COPOLYMERS OBTAINED FROM 1-OCTADECENE WITH ZIRCONOCENE CATALYSTS

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Chinese Journal of Polymer Science 2000年第3期18卷 249-254页

作者： Raul Quijada juan L.Guevara Rene Rojas franco M.Rabagliati Departamento de Ingenieria Quimica Facultad de Ciencias Fisicasy MatematicasUniversidad de ChileCasilla 2777SantiagoChile Departamento Ciencias Quimicas Facultad Quimicay BiologiaUniversidad de Santiago de ChileCasilla 40SantiagoChile

Studies related to the behavior of different metallocene catalysts for the homopolymerization of 1-octadecene andits copolymerization with ethylene will be *** metallocenes:rac-Et(Ind)_(2)ZrCl_(2),rac-Me_(2)Si(Ind)_(2)ZrCl_(2)andPh_(2)C(Flu)(Cp)ZrCl_(2)were chosen for the homopolymerization *** show important differences in catalytic activity athigh temperatures(≥70℃),with rac-Et(Ind)_(2)ZrCl_(2)showing the highest *** lower temperatures(≤30℃)thedifferences are *** the copolymerization of ethylene with 1-octadecene only the catalysts rac-Et(Ind)_(2)ZrCl_(2)andrac-Me_(2)Si(Ind)_(2)ZrCl_(2)were *** results show that their catalytic activity is just like that for the homopolymerizationof 1-octadecene,with higher activity for the metallocene with the Et-bridged catalyst.^(13)C-NMR analysis shows that thecomposition of the copolymerization products depends on the catalytic *** obtained with rac-Me_(2)Si(Ind)_(2)ZrCl_(2)have greater comonomer *** analysis shows that poly-1-octadecene synthesized withthe catalyst rac-Et(Ind)_(2)ZrCl_(2)is very dependent on the polymerization *** homopolymer obtained at 70℃presents two endothermal peaks at 41℃and 53℃,as compared with the one obtained at 30℃which presents one wider peakwith a maximum at 67℃.For the catalyst rac-Me_(2)Si(Ind)_(2)ZrCl_(2)this trend is not *** type of metallocene and thereaction time do not significantly change the intrinsic viscosity,but the polymerization temperature changes it drastically,giving higher values at lower *** measurements on the copolymers show that an increase of comonomerconcentration in the feed reduces the molecular weight of the copolymer,and it was also found that for homopolymer,themolecular weight is independent of the catalytic systems.

关键词： Homopolymerization Copolymerization Metallocene Catalytic activity Poly-l-octadecene

Canola and Oat Forage Potential Evaluation in Four Early Planting Dates

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Phyton-International Journal of Experimental Botany 2019年第4期88卷 435-448页

作者： juan isidro Sánchez-Duarte David Guadalupe Reta-Sánchez JoséAntonio Cueto-Wong Arturo Reyes-González Esmeralda Ochoa-Martínez Campo Experimental La Laguna Instituto Nacional de Investigaciones ForestalesAgrícolas y Pecuarias(INIFAP).Blvd.JoséSantos Valdez 1200 Pte.Col.CentroMatamorosCoahuilaCP 27440México

Canola and oat forage potential may be affected by climatic conditions when sown *** objective of this study was to evaluate the forage canola and oat potential in four early sowing dates(September 11 and 25;October 9 and 23)during the 2012-2013 and 2013-2014 cycles in Matamoros,Coahuila,*** cycle duration,chemical composition,dry matter(DM),crude protein(CP),and net energy for lactation(NEL)yields were *** temperatures and long photoperiods affected crops seeded on September 11,accelerating growth and reducing canola(26.6%-31.7%)and oat(15.8%)DM *** of September 25,canola cv IMC 205 reached DM yields(7746 kg ha^(-1)-9276 kg ha^(-1))similar to those obtained by oat(8115 kg ha^(-1)-9507 kg ha^(-1)),while canola cv Hyola 401 obtained such yields only until October *** chemical composition was better than that found in oat,with higher CP,but lower acid detergent fiber(ADF)and neutral detergent fiber(NDF)*** equaled oat CP yields(972 kg ha^(-1)-1215 kg ha^(-1))in the first sowing date,while in the other three other canola sowings reached higher yields(1193 kg ha^(-1)-1889 kg ha^(-1)).As for NEL yields,no difference was observed between both *** best sowing date for canola is from September 25 on,with CP production advantages over oat.

关键词： Avena sativa L. Brassica napus L.var.oleifera chemical composition dry matter yield nutrients

Pancreatic adenosquamous carcinoma and intraductal papillary mucinous neoplasm in a CDKN2A germline mutation carrier

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World Journal of Gastrointestinal Oncology 2017年第9期9卷 390-396页

作者： Fernando Martínez de juan María Reolid Escribano Carmen Martínez Lapiedra Fernanda Maia de Alcantara María Caballero Soto Ana Calatrava Fons isidro Machado Gastroenterology and Digestive Endoscopy Department Valencian Institute of Oncology Digestive Surgery Department Valencian Institute of Oncology Pathology Department Valencian Institute of Oncology

A 69-year-old woman from a kindred with familial atypical multiple mole melanoma and carrier of a germline mutation in CDKN2A, presented with abdominal pain caused by a solid-cystic pancreatic mass. The patient had an abdominal computed tomography three years before in which there was no evidence of pancreatic lesion. The endoscopic ultrasound guided fine needle aspiration showed adenocarcinoma with squamous component. After surgical resection the final diagnosis was adenosquamous pancreatic carcinoma(ASPC) arising in an intraductal papillar mucinous neoplasm(IPMN). Adenosquamous carcinomas are uncommon in the pancreas and have rarely been described in association with IPMNs. It has worse prognosis than the ordinary pancreatic ductal adenocarcinoma and some distinct features. We review the clinical, imaging, pathologic and molecular aspects of ASPC. Differential diagnosis with contamination, squamous metaplasia and pancreatic metastases from a distant squamous carcinoma is discussed. Besides, the case is an accelerated model of the adenoma(IPMN)-carcinoma sequence probably due to the CDKN2A ger-mline mutation. Somatic CDKN2A mutations are commonevents in the early steps of sporadic pancreatic cancer, but germline mutation carriers have a significantly higher risk of pancreatic carcinoma.

关键词： Intraductal papillary mucinous neoplasia Melanoma-pancreatic cancer syndrome Adenosquamous carcinoma Pancreatic carcinoma CDKN2A

Arabidopsis SWC4 Binds DNA and Recruits the SWR1 Complex to Modulate Histone H2A.Z Deposition at Key Regulatory Genes

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Molecular Plant 2018年第6期11卷 815-832页

作者： Angeles Gomez-Zambrano Pedro Crevillen Jose M. franco-Zorrilla juan A. Lopez Jordi Moreno-Romero Pawel Roszak juan Santos-Gonzalez Silvia Jurado Jesus Vazquez Claudia Kohler Roberto Solano Manuel Pineiro Jose A. Jarillo Centro de Biotecnologia y Genomica de Plantas Universidad Politecnica de Madrid (UPM) - Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria (INIA) Campus Montegancedo UPM Pozuelo de Alarcon 28223 Madrid Spain Plant Molecular Genetics Department and Genomics Unit Centro Nacional de Biotecnologia Consejo Superior de Investigaciones Cientfficas 28049 Madrid Spain Proteomics Unit Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC) 28029 Madrid Spain Department of Plant Biology Uppsala BioCenter Swedish University of Agricultural Sciences and Linnean Center for Plant Biology Uppsala 75652 Sweden Laboratory of Cardiovascular Proteomics Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC) 28029 Madrid Spain Instituto de Bioquimica Vegetal y Fotosintesis Consejo Superior de Investigaciones Cientfficas and Universidad de Sevilla 41092 Sevilla Spain Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB Campus UAB Bellaterra Barcelona Spain The Sainsbury Laboratory Cambridge CB2 1LR UK

Deposition of the H2A.Z histone variant by the SWR1 complex （SWRI-C） in regulatory regions of specific loci modulates transcription. Characterization of mutations in Arabidopsis thaliana homologs of yeast SWRI-C has revealed a role for H2A.Z exchange in a variety of developmental processes. Nevertheless, the exact composition of plant SWRI-C and how it is recruited to target genes remains to be established. Here we show that SWC4, the Arabidopsis homolog of yeast SANT domain protein Swc4/Eaf2, is a DNA-binding protein that interacts with SWR1-C subunits. We demonstrate that the swc4-1 knockout mutant is embryo- lethal, while SWC4 RNAi knockdown lines display pleiotropic phenotypic alterations in vegetative and repro- ductive traits, including acceleration of flowering time, indicating that SWC4 controls post-embryonic processes. Transcriptomic analyses and genome-wide profiling of H2A.Z indicate that SWC4 represses tran- scription of a number of genes, including the floral integrator FT and key transcription factors, mainly by modulating H2A.Z deposition. Interestingly, SWC4 silencing does not affect H2A.Z deposition at the FLC locus nor expression of this gene, a master regulator of flowering previously shown to be controlled by SWR1-C. Importantly, we find that SWC4 recognizes specific AT-rich DNA elements in the chromatin regions of target genes and that SWC4 silencing impairs SWRI-C binding at FT. Collectively, our data suggest that SWC4 regulates plant growth and development by aiding SWR1-C recruitment and modulating H2A.Z deposition.

关键词： Arabidopsis SWC4 chromatin SWR1 complex H2A.Z deposition flowering time

Effect of human disturbance on the structure and regeneration of forests in the Nevado de Toluca National Park, Mexico

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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

Immunomodulatory oligonucleotide IMT504:Effects on mesenchymal stem cells as a first-in-class immunoprotective/immunoregenerative therapy

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World Journal of Stem Cells 2017年第3期9卷 45-67页

作者： Jorge Zorzopulos Steven M Opal Andrés Hernando-Insúa juan M Rodriguez Fernanda Elías juan Fló Ricardo A López Norma A Chasseing Victoria A Lux-Lantos Maria F Coronel Raul franco Alejandro D Montaner David L Horn Immunotech S.A. Ciudad de Buenos Aires C1440FFXArgentina Infectious Disease Division Memorial Hospital of Rhode Island and Alpert Medical SchoolProvidenceRI 02905United States Fundación Pablo Cassara Ciudad Autonoma de Buenos Aires C1440FFXArgentina Instituto de Biología y Medicina Experimental(IBYME-CONICET) Ciudad Autónoma de Buenos Aires C1428ADNArgentina Instituto de Ciencia y Tecnolog'DR.Cesar Milstein” Fundación Pablo CassaráCiudad Autonoma de Buenos Aires C1440FFXArgentina David Horn LLC DoylestownPA 18902United States

The immune responses of humans and animals to insults(i.e., infections, traumas, tumoral transformation and radiation) are based on an intricate network of cells and chemical messengers. Abnormally high inflammation immediately after insult or abnormally prolonged proinflammatory stimuli bringing about chronic inflammation can lead to life-threatening or severely debilitating diseases. Mesenchymal stem cell(MSC) transplant has proved to be an effective therapy in preclinical studies which evaluated a vast diversity of inflammatory conditions. MSCs lead to resolution of inflammation, preparation for regeneration and actual regeneration, and then ultimate return to normal baseline or homeostasis. However, in clinical trials of transplanted MSCs, the expectations of great medical benefit have not yet been fulfilled. As a practical alternative to MSC transplant, a synthetic drug with the capacity to boost endogenous MSC expansion and/or activation may also be effective. Regarding this, IMT504, the prototype of a major class of immunomodulatory oligonucleotides, induces in vivo expansion of MSCs, resulting in a marked improvement in preclinical models of neuropathic pain, osteoporosis, diabetes and sepsis. IMT504 is easily manufactured and has an excellent preclinical safety record. In the small number of patients studied thus far, IMT504 has been well-tolerated, even at very high dosage. Further clinical investigation is necessary to demonstrate the utility of IMT504 for resolution of inflammation and regeneration in a broad array of human diseases that would likely benefit from an immunoprotective/immunoregenerative therapy.

关键词： Immunohomeostasis Immunoprotection Immunoregeneration Inflammation Mesenchymal stem cells IMT504

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关于研究和机器人:让偶然的发现说得通

英国医学杂志中文版 2022年第10期25卷 555-556页

作者： juan Victor Ariel franco Santiago Esteban 夏鹏(译) BMJ Eridence-Based Medicine Information Management and Health Statistics Office Hospital Italiano de Buenos AiresArgentina 中国医学科学院北京协和医院

当我们解读医疗相关研究时,我们必须确保人工智能的应用带来的是帮助而非伤害。面对困惑的主人Donovan和Powel,机器人QT-1(Cutie)说道,“我,一个理性的存在,能够从先天的原因中推导出真理。而你们,尽管智慧却不理智,则需要一个存在的理... 详细信息

当我们解读医疗相关研究时,我们必须确保人工智能的应用带来的是帮助而非伤害。面对困惑的主人Donovan和Powel,机器人QT-1(Cutie)说道,“我,一个理性的存在,能够从先天的原因中推导出真理。而你们,尽管智慧却不理智,则需要一个存在的理由。”这是伊萨克·阿西莫夫经典小说《我,机器人》(I,Robot)1中的一幕。在书中,在人工智能(AI)的强大支持下,反叛的机器人控制了一个空间站,他们相信人类过于弱小,无法创造出机器人这样的高等“生物”。

关键词：机器人控制 Robot 阿西莫夫 Cut 伊萨克 QT 《我,机器人》存在的理由

How Do People Understand Urban Air Pollution? Exploring Citizens’ Perception on Air Quality, Its Causes and Impacts in Colombian Cities

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Open Journal of Air Pollution 2017年第1期6卷 1-17页

作者： Omar Ramírez Ivan Mura juan Felipe franco Environmental Engineering Program Group of Applied Environmental Studies—GEAA Universidad Nacional Abierta y a Distancia—UNAD Bogotá Colombia Associate Unit CSIC-University of Huelva “Atmospheric Pollution” Centre of Research in Sustainable Chemistry—CIQSO Campus de El Carmen s/n Huelva Spain COPA Research Group Department of Industrial Engineering Universidad de los Andes Bogotá Colombia Group of Studies on Urban and Regional Sustainability (SUR) School of Engineering Universidad de los Andes Bogotá Colombia

Similarly to other Latin American countries, urban air quality is a major concern in Colombia. The purpose of the present study was to explore citizens’ perception on local air pollution, its causes and impacts. A questionnaire was individually applied to a sample of 994 participants. Relationships between demographic features and the perception on air quality were analyzed using a logistic regression, its odds ratio (OR), and a Chi-square test. Eighty percent of the respondents perceive their local air quality as either bad or fair, 65% recognize particulate matter as the main local air pollutant, and 90% recognize negative impacts on people’s health as the main consequence of air pollution. In contrast to other studies where age and economic status are variables highly related with public perception on the level of atmospheric pollution, in this study only the size of the cities has a statistically significant relationship with the perception on local air quality regarding the level of pollution(OR ≥ 1, confidence intervals > 1 and p-values < 0.05). While area sources such as mining and infrastructure construction are identified as the main sources of pollutant emissions in small towns (less than 50,000 inhabitants), in big cities, road traffic is identified as the main source contributor to atmospheric pollution. Opposite to data from official reports, and regardless of the size of the city, households are perceived as the place with greatest contribution to personal air pollution exposure. Results show that citizens are aware of the state of air quality and its health impact is a major concern. Such findings suggest people’s opinions can be used as provisional indicators in cities without data, as well as to monitor the results of local air quality management. As a complementary process, or at the same level of importance given to technical-based policy, citizen participation can contribute to a collective construction of urban air pollution control strategies.

关键词： Public Perception Citizen Participation Air Quality Air Pollution Colombia