773 research outputs found

    Climate projections of chill hours and implications for olive cultivation in Minas Gerais, Brazil

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    O objetivo deste trabalho foi determinar o acúmulo de horas de frio e definir as áreas com aptidão para a olivicultura (Olea europaea) no estado de Minas Gerais, Brasil, assim como analisar os impactos das projeções de mudanças climáticas na exigência de horas de frio e no zoneamento climático, em dois cenários de forçantes radiativas. O método trigonométrico foi utilizado para quantificar o número de horas de frio, tendo-se considerado temperaturas basais (Tb) de 7,0, 9,5 e 13°C (frio intenso, médio e suave, respectivamente), e foi aplicado para condições climáticas do presente (1983–2012) e para duas condições climáticas futuras (2041–2070 e 2071–2100). Os dados do clima presente foram obtidos de 47 estações meteorológicas convencionais, e os de clima futuro foram obtidos de três modelos do sistema terrestre (IPSL-CM5A-LR, MRI-CGCM3 e MIROC5). As projeções futuras apontam para uma diminuição das áreas aptas ao cultivo de oliveira, principalmente sob caminhos representativos de concentração (RCP) 8.5 e de cultivares com maior exigência em frio (Tb=7,0ºC). Das cultivares de média exigência em frio (Tb=9,5oC), apenas 2,6% (RCP 4.5) e 1,6% (RCP 8.5) serão aptas no extremo sul e nas áreas de maior altitude de Minas Gerais, enquanto, das de baixa exigência (Tb=13ºC), 11,8% (RCP4.5) e 6,7% (RCP 8.5) serão aptas. Se as condições climáticas se realizarem, o cultivo de oliveira será viável na região sul e em áreas de maior altitude no estado de Minas Gerais.The objective of this work was to determine the accumulation of chill hours and to define the areas with aptitude for olive (Olea europaea) cultivation in the state of Minas Gerais, Brazil, as well as to analyze the impacts of climate change projections on chilling-hour requirements and climatic zoning, in two radiative forcing scenarios. The trigonometric method was used to quantify the number of chill hours, considering base temperatures (Tb) of 7.0, 9.5, and 13°C (high, medium, and low chill, respectively), and was applied to present climate (1983–2012) and to two future climate (2041–2070 and 2071–2100) conditions. The present climate data were obtained from 47 conventional weather stations, and the future climate data were obtained from three Earth system models (IPSL-CM5A-LR, MRI-CGCM3, and MIROC5). Future projections point to a decrease in the suitable areas for olive crop cultivation, particularly under representative concentration pathway (RCP) 8.5 and for olive cultivars with a high-chilling requirement (Tb=7.0ºC). Of the olive cultivars requiring medium chill (Tb=9.5ºC), only 2.6% (RCP 4.5) and 1.6% (RCP 8.5) will be suitable in the extreme south and in higher altitude areas of Minas Gerais, while, of those requiring low chill (Tb=13ºC), 11.8% (RCP 4.5) and 6.7% (RCP 8.5) will be suitable. If the climate projections become true, the cultivation of olive crops will be viable in the southern region and in higher altitude areas of the state of Minas Gerais

    ASPECTOS CLIMATOLÓGICOS ASSOCIADOS AO CULTIVO DA OLIVEIRA (Olea europaea L.) EM MINAS GERAIS

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    No intuito de suprir as necessidades do consumo interno de azeite e azeitona, muitos produtores no Brasil, mais especificamente no sul de Minas Gerais, têm investido nesse cultivo. Entretanto, para viabilizar a expansão da olivicultura é necessário conhecer as condições climáticas limitantes ao seu cultivo, principalmente em relação a eventos extremos de temperatura e precipitação; que são os maiores limitantes à olivicultura. Por isso, o objetivo deste estudo é determinar as áreas climatologicamente aptas ao cultivo da oliveira, em Minas Gerais. Para isso, foram calculadas as climatologias mensais de precipitação e das temperaturas média, máxima e mínima do ar; para o período de 1981 a 2010, em 49 estações meteorológicas de Minas Gerais. Também foram calculados os percentis para determinação de eventos extremos de precipitação (P5 e P95), temperatura máxima (T90) e mínima (T10); além de contabilizar o número de casos com temperatura inferior a 9,5°C e superior a 30°C. Por fim, foi analisado a relação da quantidade dos eventos extremos com as fases fenológicas da oliveira. Os eventos de temperatura inferior a 9,5°C, ocorrem com maior frequência (≥1500 eventos) na região sul do estado. Com relação a eventos de temperatura superior a 30°C, há um maior número de casos (≥1000 eventos) no noroeste, norte, Vales do Jequitinhonha e Mucuri, Central e Triângulo Mineiro. Já a precipitação não inviabiliza o cultivo de oliveira em Minas Gerais, principalmente pela possibilidade de irrigação suplementar nas regiões com maiores registros de P5 e pelo pequeno número de casos (≤ 24 eventos) de P95. Somente as regiões sul e pequena parte do centro-oeste de Minas Gerais possuem características climáticas favoráveis ao cultivo de oliveir

    Environmental and Climatic Perception of Students from Public Schools of Itajubá - MG

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    A percepção é o processo no qual o indivíduo assimila os estímulos externos, os internaliza por meio do processo cognitivo e a eles atribui significado. Nesse sentido, a percepção ambiental e climática pode ser compreendida como a forma pela qual os indivíduos entendem os fenômenos naturais que se manifestam no seu cotidiano. O objetivo do presente estudo é conhecer a percepção ambiental e climática de estudantes de escolas públicas municipais de Itajubá-MG. Foram selecionadas quatro escolas, duas localizadas na área rural e duas localizadas na área urbana do município. Adotou-se uma estratégia metodológica quantiqualitativa, com aplicação de questionários e observação dos estudantes ao longo do ano de 2016. As análises apontaram que os estudantes não se reconhecem como integrantes do sistema atmosférico e que os estudantes inseridos no meio rural não demonstraram possuir uma percepção ambiental e climática diferenciada dos estudantes de escolas urbanas, no que se refere a descrição de elementos do meio natural e atmosférico.Perception is the process by which the individual assimilates external stimuli, internalizes them, through the cognitive process, and assigns them meaning. Hence, environmental and climatic perception is the form what individuals understand natural phenomena that happens in their daily life. Accordingly, the objective of this study is to get to know the environmental and climatic perception of fifth-year elementary students of municipal public schools in Itajubá, MG. Four schools were selected to perform the study, two in the rural area and two in the urban area of the municipality. A quantitative-qualitative methodological strategy was adopted through the application of questionnaires and observations performed throughout the year 2016, to attend both the objectives of the university extension project Amigos do Clima and this perception research. The analyzes indicated that presented the same difficulty: to perceive themselves as belonging to the atmospheric environment; and that students that come from rural areas do not necessarily have a more accurate environmental and climatic perception than students attending schools in the urban area.   &nbsp

    POTENCIAL ANTIBACTERIANO DO COGUMELO COMESTÍVEL Pleurotus ostreatus FRENTE À Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853 E Escherichia coli ATCC 25922

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    Este trabalho reporta o potencial antibacteriano do cogumelo comestível Pleurotus ostreatus. Extratos orgânicos, bem como β-glucânico e quitosânico, ambos nas concentrações de 100, 300 e 500 ppm, foram submetidos a ensaios de disco-difusão contra quatro bactérias padrões: duas Gram positivas (Staphylococcus aureus ATCC 25923 e Enterococcus faecalis ATCC 29212) e duas Gram negativas (Escherichia coli ATCC 25922 e Pseudomonas aeruginosa ATCC 27853). Os extratos que apresentaram halo de inibição (HI) do crescimento bacteriano iguais a 8 mm foram classificados como ativos. Dos extratos testados, o extrato β-glucânico se mostrou ativo, em ambas concentrações, contra a bactéria Pseudomonas aeruginosa ATCC 27853 e na concentração de 500 ppm contra as bactérias Staphylococcus aureus ATCC 25923 e Escherichia coli ATCC 25922. O extrato quitosânico apresentou atividade somente contra Pseudomonas aeruginosa ATCC 27853 na concentração de 500 ppm. Estes resultados são considerados promissores, pois apontam o extrato β-glucânico com potencial contra bactérias Gram positivas e Gram negativas. Futuros estudos bioguiados sob a ação antibacteriana desse extrato devem ser realizados para produção, purificação e caracterização físico-química do constituinte bioativo de interesse farmacológico

    Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

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    A measurement of the cosmic-ray spectrum for energies exceeding 4×10184{\times}10^{18} eV is presented, which is based on the analysis of showers with zenith angles greater than 6060^{\circ} detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above 5.3×10185.3{\times}10^{18} eV, the "ankle", the flux can be described by a power law EγE^{-\gamma} with index γ=2.70±0.02(stat)±0.1(sys)\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)} followed by a smooth suppression region. For the energy (EsE_\text{s}) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find Es=(5.12±0.25(stat)1.2+1.0(sys))×1019E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19} eV.Comment: Replaced with published version. Added journal reference and DO

    Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

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    The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

    The 13th Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-IV Survey Mapping Nearby Galaxies at Apache Point Observatory

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    The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) began observations in July 2014. It pursues three core programs: APOGEE-2,MaNGA, and eBOSS. In addition, eBOSS contains two major subprograms: TDSS and SPIDERS. This paper describes the first data release from SDSS-IV, Data Release 13 (DR13), which contains new data, reanalysis of existing data sets and, like all SDSS data releases, is inclusive of previously released data. DR13 makes publicly available 1390 spatially resolved integral field unit observations of nearby galaxies from MaNGA,the first data released from this survey. It includes new observations from eBOSS, completing SEQUELS. In addition to targeting galaxies and quasars, SEQUELS also targeted variability-selected objects from TDSS and X-ray selected objects from SPIDERS. DR13 includes new reductions ofthe SDSS-III BOSS data, improving the spectrophotometric calibration and redshift classification. DR13 releases new reductions of the APOGEE-1data from SDSS-III, with abundances of elements not previously included and improved stellar parameters for dwarf stars and cooler stars. For the SDSS imaging data, DR13 provides new, more robust and precise photometric calibrations. Several value-added catalogs are being released in tandem with DR13, in particular target catalogs relevant for eBOSS, TDSS, and SPIDERS, and an updated red-clump catalog for APOGEE.This paper describes the location and format of the data now publicly available, as well as providing references to the important technical papers that describe the targeting, observing, and data reduction. The SDSS website, http://www.sdss.org, provides links to the data, tutorials and examples of data access, and extensive documentation of the reduction and analysis procedures. DR13 is the first of a scheduled set that will contain new data and analyses from the planned ~6-year operations of SDSS-IV.PostprintPeer reviewe

    Les droits disciplinaires des fonctions publiques : « unification », « harmonisation » ou « distanciation ». A propos de la loi du 26 avril 2016 relative à la déontologie et aux droits et obligations des fonctionnaires

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    The production of tt‾ , W+bb‾ and W+cc‾ is studied in the forward region of proton–proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98±0.02 fb−1 . The W bosons are reconstructed in the decays W→ℓν , where ℓ denotes muon or electron, while the b and c quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions.The production of ttt\overline{t}, W+bbW+b\overline{b} and W+ccW+c\overline{c} is studied in the forward region of proton-proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98 ±\pm 0.02 \mbox{fb}^{-1}. The WW bosons are reconstructed in the decays WνW\rightarrow\ell\nu, where \ell denotes muon or electron, while the bb and cc quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions

    Mitochondrial physiology

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    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery
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