1,871 research outputs found
Sociocriosfera andina : etnoconhecimento ancestral e a ruptura pĂłs-colonial nos Andes centrais
As populaçþes que habitam as regiĂľes periglaciais nos Andes Centrais tem sido vulnerĂĄveis aos desastres glaciais. Portanto, ĂŠ importante compreender os impactos das mudanças climĂĄticas sobre as geleiras e como os riscos climĂĄticos, como o rompimento de dique de lagoas glaciais, tem sido manejado nos Andes peruanos. Na Cordilheira Branca, Peru, o aquecimento atmosfĂŠrico regional estĂĄ provocando a crescente retração das geleiras e de forma mais acelerada a partir da dĂŠcada de 1930. Diante do pouco conhecimento que se tem a respeito de como as diferentes populaçþes percebem e respondem Ă s mudanças climĂĄticas, esta tese sugere que a cultura e sua anĂĄlise sejam elementos centrais para a identificação, compreensĂŁo e proposição de estratĂŠgias de adaptação Ă s mudanças climĂĄticas e desastres glaciais na regiĂŁo da Cordilheira Branca. O conceito proposto nesta tese surge diante da necessidade de uma releitura histĂłrica e geogrĂĄfica a partir de uma perspectiva descolonial. Destarte, a sociocriosfera cultural andina denota uma longa e continuada ocupação humana em uma regiĂŁo glacial e periglacial nas grandes altitudes montanhosas â onde desenvolveu-se uma cultura e uma cognição tĂpicas para essa regiĂŁo. Contudo, essa proposição de sociocriosfera implica consequentemente numa segunda tese: houve uma ruptura adaptativa com a emergĂŞncia da sociedade pĂłs-colonial, desencadeando um processo de desadaptação civilizatĂłria nos Andes Centrais. O objetivo geral ĂŠ identificar e compreender os fatores e elementos que compĂľem a sociocriosfera cultural andina, num contexto de mudanças climĂĄticas. Para essa investigação, propĂľem-se quatro movimentos de pesquisa. O primeiro movimento debruça-se sobre o etnoconhecimento ancestral e sua ruptura pĂłs-colonial, onde se sustenta a hipĂłtese de que hĂĄ uma cultura ancestral adaptada ao ambiente periglacial de montanha; porĂŠm, hĂĄ uma ruptura adaptativa com a emergĂŞncia da sociedade pĂłs-colonial. No segundo, investiga-se os desdobramentos sĂłcio-territoriais dos desastres glaciais sobre os habitantes da regiĂŁo e sustenta-se a hipĂłtese de que os diferentes grupos sociais que ali vivem sofrem distintas consequĂŞncias socioambientais, sendo uns mais resilientes que outros. No terceiro movimento, foram analisadas as estratĂŠgias de adaptação Ă s mudanças socioambientais. Aqui, sugere-se a hipĂłtese de que o modelo de sociedade pĂłs-colonial tende a complexificar possĂveis estratĂŠgias de adaptação Ă s mudanças climĂĄticas. As prĂĄticas socioculturais e econĂ´micas, abordadas no quarto movimento, sĂŁo escrutinadas com o intuito de sustentar a hipĂłtese de que as geleiras sĂŁo parte indissociĂĄvel da cultura andina e suscitam vĂnculos identitĂĄrios entre as comunidades campesinas e comunidades urbanas da Cordilheira Branca. Para o teste dessas hipĂłteses, utilizou-se vĂĄrios mĂŠtodos, dentre os quais: cartografia, anĂĄlise de dados sobre histĂłrico de desastres, etnografia, entrevistas semiestruturadas e mapeamento participativo. Os resultados mostram que as sociedades ancestrais andinas utilizaram a seleção de lugares para minimizar o risco de desastres glaciais. No entanto, os colonizadores espanhĂłis nĂŁo valorizaram as estratĂŠgias adaptativas sustentadas pela etnocognição andina. A principal estratĂŠgia de adaptação Ă s mudanças ambientais utilizada pelas comunidades campesinas ĂŠ a escolha de locais seguros para a moradia. Essa prĂĄtica estĂĄ mais relacionada Ă uma herança ancestral das civilizaçþes prĂŠ- colombianas do que um senso moderno de preocupação em relação Ă s ĂĄreas de alto risco. O mapeamento participativo ĂŠ uma excelente ferramenta metodolĂłgica que abre espaço para a discussĂŁo sobre experiĂŞncias de conhecimentos locais, percepçþes e conflitos existentes nas comunidades campesinas e pode ajudar a conceber o contexto para o avanço da adaptação.Populations inhabiting the periglacial regions of the Central Andes have always been vulnerable to glacier-related hazards. Therefore, it is important to understand climate change impacts on glacier and how climate risks like glacial lake outburst floods (GLOFs) in the Peruvian Andes have been managed. Since the 1930s, regional atmospheric warming has caused glaciers to shrink more rapidly in the Cordillera Blanca, Peru. We know little about how different populations perceive and respond to climate variability in the Andes; this thesis suggests that culture and its analysis are central elements for the identification, understanding, and response to climatic changes and glacier-related disasters in the Cordillera Blanca region. This thesis addresses the need for a historical and geographical reinterpretation from a decolonial perspective. The Andean cultural socio-cryosphere denotes a long and continuous human occupation over a glacial and periglacial region on the mountains where a typical culture and cognition for this region were developed. However, this proposition of the socio-cryosphere implies a second thesis: there was an adaptive rupture with the emergence of post-colonial society, triggering a process of civilization maladjustment in the Central Andes. The general objective is to identify and understand the factors and elements that make up the Andean cultural socio-cryosphere in the context of climate change. For this investigation, four research themes are presented. The first focuses on ancestral ethno-knowledge and its post-colonial rupture, which supports the hypothesis that there is an ancestral culture adapted to the periglacial mountain environment; however, there is an adaptive rupture with the emergence of postcolonial society. In the second, the socio- territorial impacts of the glacier-related disasters on the inhabitants of the region are investigated and the hypothesis that the different social groups who live there suffer different socio-environmental consequences, some of which are more resilient than others. In the third theme, adaptation strategies to socio-environmental changes were analyzed under the hypothesis that the post-colonial society model tends to make complex possible strategies for adapting to climate change. Sociocultural practices, addressed in the fourth theme, are scrutinized to support the hypothesis that glaciers are an inseparable part of Andean culture and raise identity ties between the campesino and urban communities of the Cordillera Blanca. Several methods are used to test these hypotheses, including cartography, data analysis on disaster history, ethnography, semi-structured interviews, and participatory mapping. The results show that ancestral Andean societies selected settlement sites to minimize the risk of glacier-related disasters. However, the Spanish colonizers did not appear to value the adaptive strategies supported by an Andean ethno-cognition. The main strategy for adapting to environmental changes used by campesino communities is the choice of safe places for housing. This practice is more related to an ancestral heritage of pre-Columbian civilizations than to a modern sense of concern for high-risk areas. Finally, participatory mapping as a methodological tool opens space for discussions about experiences of local knowledge, perceptions, and conflicts existing in campesino communities, and can help frame the context for adaptation moving forward
Monte Esperança : múltiplos olhares sob o Conjunto Residencial Rubem Berta, Porto Alegre-RS
As periferias das cidades e seus moradores sĂŁo representadas por estigmas que se (re)produzem com marcas de um estereĂłtipo imutĂĄvel, atravĂŠs de valores depreciativos que atribuem a elas as mazelas da cidade. Contudo, ĂŠ importante investigar se a cultura destas populaçþes ĂŠ formada apenas por carĂŞncias e violĂŞncias, como faz crer o discurso Ăşnico â registrado como um geografismo â que ĂŠ constituĂdo para estes lugares. Nessa perspectiva, como o bairro Rubem Berta abrange uma ĂĄrea de grande extensĂŁo, com uma sĂŠrie de loteamentos, vilas e conjuntos habitacionais, cada um com suas especificidades, a presente pesquisa investiga os olhares que apreendem um desses conjuntos habitacionais, o Conjunto Residencial Rubem Berta â Porto Alegre, RS. Trata-se de um estudo de caso que faz uma anĂĄlise a partir dos conceitos de lugar e paisagem, buscando compreender na percepção de moradores e lideranças e de nĂŁo-moradores que trabalham no bairro os diferentes sentidos que estes indivĂduos atribuem a este lugar. A abordagem do trabalho seguiu a linha da Geografia Cultural e HumanĂstica como diretriz investigatĂłria, baseando-se nos relatos locais, nos relatos nĂŁo-locais, nos dados do IBGE e em reportagens jornalĂsticas, tendo como mĂŠtodo a AnĂĄlise de Discurso. As anĂĄlises permitiram reconhecer que as experiĂŞncias topofĂlicas coexistem em muitos casos com experiĂŞncias topofĂłbicas, evidenciando, por meio destas vivĂŞncias, uma infinidade de olhares sob o conjunto habitacional. Nesse sentido, o estudo permitiu a leitura do Conjunto Residencial Rubem Berta, nĂŁo como o discurso Ăşnico o expressa, ou seja, como algo homogĂŞneo, mas sim como um lĂłcus de pluralidades, de pensamentos, de ideias e ideais que expressam o conjunto habitacional como heterogeneidade, repleto de especificidades.The periphery of cities and their residents are represented by stigmas that are (re)produce with marks an immutable stereotype through derogatory values to assign to them the cityâs ills. However, it is important to investigate whether the culture of these populations is formed only by deprivation and violence, as does believe the only speech â registered as a geographism â which is made for these places. In this perspective, as the Rubem Berta neighborhood covers a large expanse of area, with a number of settlements, villages and housing developments, each with its specific features, this research investigates the looks seizing one of these housing complexes, the Residential Complex Rubem Berta â Porto Alegre, RS. This is a case study that analyzes based on the concepts of place and landscape, trying to understand the perception of residents and leaders and non-residents (who work in the neighborhood) the different meanings that these individuals attribute to this place. The approach to work followed the line of the Cultural and Humanistic Geography as investigative directive, based on local reports, the non-local reports, the IBGE data and newspaper reports, with the method Discourse Analysis. The analysis allows to recognize that topophilics experiences coexist in many cases with topophobics experiences, showing, through these experiences, an infinities of looks in the housing complex. In this sense, the study allowed the reading of the Residential Complex Rubem Berta, not as the only speech expresses, that is, as something homogeneous, but as a locus of pluralities of thoughts, ideas and ideals that express the housing as heterogeneity, full of specifics
The use of automatic relief mapping methods for analysis of glacial forms
O mapeamento geomorfolĂłgico de ambientes glaciais pode ser mais preciso com a aplicação da classificação digital gerada por Modelos Digitais de Elevação (MDEs). Este artigo avalia o potencial da metodologia geomorphon para a identifi cação de tipos de formas de relevo em ambientes glaciais de montanha. SĂŁo propostas novas nomenclaturas para a classificação obtida diretamente por geomorphon quando aplicado ao mapeamento geomorfolĂłgico glacial. O mĂŠtodo serĂĄ chamado de Classificação Digital Revisada por Elementos de Geomorphon (Revised Geomorphon Digital Classifi cation â RGDC). Parâmetros morfomĂŠtricos e hidrolĂłgicos, extraĂdos dos MDEs SRTMGL 1 e ALOS PALSAR, em um setor da Cordilheira Branca, Peru, foram utilizados na nova proposta de classificação. As classes identifi cadas foram interpretadas como formas de picos piramidais (horns), arestas (arĂŞtes), arestas fortemente retrabalhadas pelo intemperismo, morainas de avanço, encostas, vales em circo (anfi teatro), vales em U e vales em V. The class of arĂŞtes is most easily identifi ed using the geomorphons, same for horn classes. The results show the potential of the automatic method of digital classifi cation of MDEs for the mapping of glacial relief shape types. Moraines with higher topographic amplitude were easily identifi ed due to the spatial resolution and vertical accuracy of the DEMs used. The geomorphon identifi es more relief types than classical methodologies for relief identifi cation by MDEs, 7 relief types, while the Dikau et al. (1995) and ITP methods only provide 3 types. The ALOS PALSAR MDE, with higher spatial resolution, shows no diff erence in the identifi cation of relief forms. The generated mapping can improve the reconstruction of geomorphological evolution, supporting paleoglaciological interpretation and understanding of territorial occupation along the Holocene.Geomorphological mapping of glacial environments can be more accurate with the application of digital classifi cation generated by Digital Elevation Models (MDEs). This paper evaluates the potential of geomorphon methodology for the identifi cation of relief types in glacial mountain environments. New nomenclatures are proposed for the classifi cation obtained directly by geomorphon when applied to glacial geomorphological mapping. The method is called Revised Geomorphon Digital Classifi cation (RGDC). Morphometric and hydrological parameters, extracted from SRTMGL 1 and ALOS PALSAR MDEs, in a sector of the Cordillera Branca, Peru, were used in the new classifi cation proposal. The identifi ed classes were interpreted as horns, arĂŞtes, arĂŞtes strongly reworked by weathering, advancing moraines, slopes, circus valleys (amphitheater), U-valleys and V-valleys. A classe de arestas ĂŠ a mais facilmente identifi cada utilizando os geomorphons, o mesmo ocorrendo para classes de picos piramidais. Os resultados mostram o potencial do mĂŠtodo automĂĄtico de classificação digital de MDEs para o mapeamento de tipos de formas de relevo glacial. As morainas de maior amplitude topogrĂĄfi ca foram facilmente identifi cadas devido Ă resolução espacial e acurĂĄcia vertical dos MDEs utilizados. O mĂŠtodo geomorphon identifica mais tipos de relevo do que metodologias clĂĄssicas de identificação de formas de relevo por MDEs, 7 tipos de relevo, enquanto os mĂŠtodos Dikau et al. (1995) e ITP sĂł fornecem 3 tipos. JĂĄ o MDE do ALOS PALSAR, com maior resolução espacial, nĂŁo apresenta diferença na identificação de formas de relevo. O mapeamento gerado pode melhorar a reconstrução da evolução geomorfolĂłgica, apoiando a interpretação paleoglaciolĂłgica e o entendimento da ocupação territorial ao longo do Holoceno
SARS-CoV-2 reinfection caused by the P.1 lineage in Araraquara city, Sao Paulo State, Brazil
Reinfection by the severe acute respiratory syndrome coronavirus type 2 (SARS-COV-2) has been reported in many countries, suggesting that the virus may continue to circulate among humans despite the possibility of local herd immunity due to massive previous infections. The emergence of variants of concern (VOC) that are more transmissible than the previous circulating ones has raised particular concerns on the vaccines effectiveness and reinfection rates. The P.1 lineage was first identified in December 2020 in Manaus city and is now globally spread. We report the first case of reinfection of SARS-CoV-2 caused by the P.1 variant outside of Manaus. The potential of these new variants to escape naturally and vaccine- induced immunity highlights the need for a global vigilance
Hypoglycemic activity of polysaccharide fractions containing Ă-glucans from extracts of Rhynchelytrum repens (Willd.) C.E. Hubb., Poaceae
Direct evidence for phosphorus limitation on Amazon forest productivity
The productivity of rainforests growing on highly weathered tropical soils is expected to be limited by phosphorus availability1. Yet, controlled fertilization experiments have been unable to demonstrate a dominant role for phosphorus in controlling tropical forest net primary productivity. Recent syntheses have demonstrated that responses to nitrogen addition are as large as to phosphorus2, and adaptations to low phosphorus availability appear to enable net primary productivity to be maintained across major soil phosphorus gradients3. Thus, the extent to which phosphorus availability limits tropical forest productivity is highly uncertain. The majority of the Amazonia, however, is characterized by soils that are more depleted in phosphorus than those in which most tropical fertilization experiments have taken place2. Thus, we established a phosphorus, nitrogen and base cation addition experiment in an old growth Amazon rainforest, with a low soil phosphorus content that is representative of approximately 60% of the Amazon basin. Here we show that net primary productivity increased exclusively with phosphorus addition. After 2 years, strong responses were observed in fine root (+29%) and canopy productivity (+19%), but not stem growth. The direct evidence of phosphorus limitation of net primary productivity suggests that phosphorus availability may restrict Amazon forest responses to CO2 fertilization4, with major implications for future carbon sequestration and forest resilience to climate change.The authors acknowledge funding from the UK Natural Environment Research Council (NERC), grant number NE/L007223/1. This is publication 850 in the technical series of the BDFFP. C.A.Q. acknowledges the grants from Brazilian National Council for Scientific and Technological Development (CNPq) CNPq/LBA 68/2013, CNPq/MCTI/FNDCT no. 18/2021 and his productivity grant. C.A.Q., H.F.V.C., F.D.S., I.A., L.F.L., E.O.M. and S.G. acknowledge the AmazonFACE programme for financial support in cooperation with Coordination for the Improvement of Higher Education Personnel (CAPES) and the National Institute of Amazonian Research as part of the grants CAPES-INPA/88887.154643/2017-00 and 88881.154644/2017-01. T.F.D. acknowledges funds from FundacAo de Amparo a Pesquisa do Estado de SAo Paulo (FAPESP), grant 2015/50488-5, and the Partnership for Enhanced Engagement in Research (PEER) programme grant AID-OAA-A-11-00012. L.E.O.C.A. thanks CNPq (314416/2020-0)
Progress and challenges in glacial lake outburst flood research (2017â2021):a research community perspective
Glacial lake outburst floods (GLOFs) are among the most concerning consequences of retreating glaciers in mountain ranges worldwide. GLOFs have attracted significant attention amongst scientists and practitioners in the past 2 decades, with particular interest in the physical drivers and mechanisms of GLOF hazard and in socioeconomic and other human-related developments that affect vulnerabilities to GLOF events. This increased research focus on GLOFs is reflected in the gradually increasing number of papers published annually. This study offers an overview of recent GLOF research by analysing 594 peer-reviewed GLOF studies published between 2017 and 2021 (Web of Science and Scopus databases), reviewing the content and geographical focus as well as other characteristics of GLOF studies. This review is complemented with perspectives from the first GLOF conference (7-9 July 2021, online) where a global GLOF research community of major mountain regions gathered to discuss the current state of the art of integrated GLOF research. Therefore, representatives from 17 countries identified and elaborated trends and challenges and proposed possible ways forward to navigate future GLOF research, in four thematic areas: (i) understanding GLOFs - timing and processes; (ii) modelling GLOFs and GLOF process chains; (iii) GLOF risk management, prevention and warning; and (iv) human dimensions of GLOFs and GLOF attribution to climate change.Fil: Emmer, Adam. University of Graz; AustriaFil: Allen, Simon K.. Universitat Zurich; Suiza. Universidad de Ginebra; SuizaFil: Carey, Mark. University of Oregon; Estados UnidosFil: Frey, Holger. Universitat Zurich; SuizaFil: Huggel, Christian. Universitat Zurich; SuizaFil: Korup, Oliver. Universitat Potsdam; AlemaniaFil: Mergili, Martin. University of Graz; AustriaFil: Sattar, Ashim. Universitat Zurich; SuizaFil: Veh, Georg. Universitat Potsdam; AlemaniaFil: Chen, Thomas Y.. Columbia University; Estados UnidosFil: Cook, Simon J.. University Of Dundee; Reino Unido. Unesco. Centre For Water Law, Policy And Science; Reino UnidoFil: Correas Gonzalez, Mariana. Consejo Nacional de Investigaciones CientĂficas y TĂŠcnicas. Centro CientĂfico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de NivologĂa, GlaciologĂa y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de NivologĂa, GlaciologĂa y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de NivologĂa, GlaciologĂa y Ciencias Ambientales; ArgentinaFil: Das, Soumik. Jawaharlal Nehru University; IndiaFil: Diaz Moreno, Alejandro. Reynolds International Ltd; Reino UnidoFil: Drenkhan, Fabian. Pontificia Universidad CatĂłlica de PerĂş; PerĂşFil: Fischer, Melanie. Universitat Potsdam; AlemaniaFil: Immerzeel, Walter W.. Utrecht University; PaĂses BajosFil: Izagirre, EĂąaut. Universidad del PaĂs Vasco; EspaĂąaFil: Joshi, Ramesh Chandra. Kumaun University India; IndiaFil: Kougkoulos, Ioannis. American College Of Greece; GreciaFil: Kuyakanon Knapp, Riamsara. University of Oslo; Noruega. University of Cambridge; Estados UnidosFil: Li, Dongfeng. National University Of Singapore; SingapurFil: Majeed, Ulfat. University Of Kashmir; IndiaFil: Matti, Stephanie. Haskoli Islands; IslandiaFil: Moulton, Holly. University of Oregon; Estados UnidosFil: Nick, Faezeh. Utrecht University; PaĂses BajosFil: Piroton, Valentine. UniversitĂŠ de Liège; BĂŠlgicaFil: Rashid, Irfan. University Of Kashmir; IndiaFil: Reza, Masoom. Kumaun University India; IndiaFil: Ribeiro De Figueiredo, Anderson. Universidade Federal do Rio Grande do Sul; BrasilFil: Riveros, Christian. Instituto Nacional de InvestigaciĂłn En Glaciares y Ecosistemas de MontaĂąa; PerĂşFil: Shrestha, Finu. International Centre For Integrated Mountain Development Nepal; NepalFil: Shrestha, Milan. Arizona State University; Estados UnidosFil: Steiner, Jakob. International Centre For Integrated Mountain Development Nepal; NepalFil: Walker-Crawford, Noah. Colegio Universitario de Londres; Reino UnidoFil: Wood, Joanne L.. University of Exeter; Reino UnidoFil: Yde, Jacob C.. Western Norway University Of Applied Sciences; Suiz
Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV
A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay
channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7
TeV is presented. The data were collected at the LHC, with the CMS detector,
and correspond to an integrated luminosity of 4.6 inverse femtobarns. No
significant excess is observed above the background expectation, and upper
limits are set on the Higgs boson production cross section. The presence of the
standard model Higgs boson with a mass in the 270-440 GeV range is excluded at
95% confidence level.Comment: Submitted to JHE
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