854 research outputs found
Proposta de uma unidade de an?lise para a materialidade da cogni??o.
As aulas de ci?ncias s?o espa?os ocupados por um conjunto enorme de objetos e sem eles as aulas certamente seriam diferentes ou mesmo imposs?veis de acontecer. Assim, p?e-se a necessidade de se considerar o engajamento entre esses objetos e humanos para o entendimento dos processos de ensino/aprendizagem. No presente artigo apresentamos uma proposta de unidade de an?lise, denominada por n?s de figura??o cognitiva. Essa unidade est? fundamentada no enquadramento te?rico-metodol?gico da teoria ator-rede, da cogni??o distribu?da e na psicologia ecol?gica. Com essa proposta, procuramos evitar um vocabul?rio mentalista e cognitivista, bem como facilitar a visualiza??o da rede de rela??es nos processos de ensino/aprendizagem
Evaluation of the process of reabilitation of a stretch of Riparian forest in Itapemirim river watershed - ES
Este estudo foi realizado em uma ĂĄrea de floresta ciliar em processo de recuperação mediante reabilitação.A ĂĄrea de estudo estĂĄ localizada na sub-bacia hidrogrĂĄfica do rio Itapemirim, no MunicĂpio de Alegre, ES, Brasil.A ocupação e uso do solo antes da revegetação eram de pastagem com Brachiaria sp. A revegetação da ĂĄreafoi feita em 1997, com espĂŠcies autĂłctones e alĂłctones arbĂłreas, em arranjo de distribuição aleatĂłrio, em umaĂĄrea de 1,2 ha. Para a realização dos estudos foram feitos inventĂĄrios florestais nos perĂodos de 2004/2005e 2005/2006, sendo medidos os indivĂduos de hĂĄbito arbustivo e arbĂłreo com circunferĂŞncia Ă altura do peito(CAP) > 5 cm e suas alturas totais. As espĂŠcies encontradas na ĂĄrea foram identificadas e classificadas de acordocom seus grupos ecolĂłgicos, sĂndromes de dispersĂŁo e presença silvestre, sendo calculados os parâmetros florĂsticos,a estrutura vertical e a dinâmica estrutural desse povoamento. O objetivo do trabalho foi avaliar o desenvolvimentodo povoamento implantado para subsidiar prĂĄticas silviculturais quanto Ă seleção e implantação de espĂŠcies pararevegetação de ĂĄreas de floresta ciliar degradadas, em condiçþes semelhantes. Os resultados demonstraram quefoi implantado um povoamento florestal com grande diversidade de espĂŠcies e a estratificação em classes dealtura foi Ă semelhança de povoamentos heterogĂŞneos naturais. As espĂŠcies identificadas como edificadoras darevegetação da ĂĄrea estudada foram: Anadenanthera colubrina, Caesalpinia leyostachia, Acacia auriculiformis,Acacia mangium, Handroanthus serratifolius, Inga edulis, Joannesia princeps, Pterogyne nitens, Enterelobiumcontortisiliquum, Tabernaemontana hystrix e Anthocephalus indicus. A distribuição em classes de tamanho dacomunidade implantada ocorre em forma de "J" reverso, havendo a predominância de indivĂduos pioneiros emtodas as classes de CAP. A dinâmica da estrutura horizontal apontou que, para o sucesso, continuidade e desenvolvimentoda recuperação da ĂĄrea, seja monitorada a regeneração natural em relação Ă sua presença e Ă eficiĂŞncia dos fatoresbiĂłticos e abiĂłticos que nela interferem. A nĂŁo observância de indivĂduos arbustivos e arbĂłreos regenerados naturalmente,na classe de inclusĂŁo do estudo, indica a fragilidade inicial da ĂĄrea rumo Ă sustentabilidade do sistema.The study was realized in an area of riparian forest in process by means of rehabilitation. Thestudy area is located in Rio Itapemirim, in Alegre city, Brazil. The occupation and use of the soil beforethe recovery were of pasture with Brachiaria sp. The recovery of this area was in 1997, with autochthonousand allochthonous species, in casually distribution arrangement, in an area of 1,2 ha. For this studies wasrealized forest inventories in the periods of 2004/2005 and 2005/2006, being measured the arboreal individualswith circumference at breast height (CBH) and total heights. The species found in the area were identifiedand classified in this ecological groups, dispersion syndromes and wild presence, it forms calculated thefloristic parameters, the vertical structure and the structural dynamics of this plantation. The objective ofthis work went evaluate the development of the plantation implanted to subsidize practical silviculture withrelationship to the selection and plantation of species for the revegetation of degraded areas of riparianforest, in similar conditions. The results of the studies demonstrated that a forest plantation was implantedwith great diversity of species and the bedding in height classes it went to the likeness of natural heterogeneous.The species identified as builders of the plantation of the studied area were: Anadenanthera colubrina, Caesalpinia leyostachia, Acacia auriculiformis, Acacia mangium, Handroanthus serratifolius, Inga edulis, Joannesia princeps,Pterogyne nitens, Enterelobium contortisiliquum, Tabernaemontana hystrix, and Anthocephalus indicus . Theimplanted community's distribution diametric happens in reverse J shape having the pioneer individuals'predominance in all the classes of CBH. The dynamics of the horizontal structure points that for the success,continuity and development of the recovery of the area, the natural regeneration be monitored in relationto its presence and efficiency of the biotic factors and abiotic those interfere in the same. The not tree individualsobservance in natural regeneration, in the class of inclusion of the study, indicate the initial fragility of thearea heading for sustentabilidade of the system
Temporal analysis of reported cases of tuberculosis and of tuberculosis-HIV co-infection in Brazil between 2002 and 2012
Corrosion protection in sulfate medium by self-assemb films adsorbed on AA 2024 T3 aluminum alloy surface
Consistent patterns of common species across tropical tree communities
D.L.M.C. was supported by the London Natural Environmental Research Council Doctoral Training Partnership grant (grant no. NE/L002485/1). This paper developed from analysing data from the African Tropical Rainforest Observatory Network (AfriTRON), curated at ForestPlots.net. AfriTRON has been supported by numerous people and grants since its inception. We sincerely thank the people of the many villages and local communities who welcomed our field teams and without whose support this work would not have been possible. Grants that have funded the AfriTRON network, including data in this paper, are a European Research Council Advanced Grant (T-FORCES; 291585; Tropical Forests in the Changing Earth System), a NERC standard grant (NER/A/S/2000/01002), a Royal Society University Research Fellowship to S.L.L., a NERC New Investigators Grant to S.L.L., a Philip Leverhulme Award to S.L.L., a European Union FP7 grant (GEOCARBON; 283080), Leverhulme Program grant (Valuing the Arc); a NERC Consortium Grant (TROBIT; NE/D005590/), NERC Large Grant (CongoPeat; NE/R016860/1) the Gordon and Betty Moore Foundation the David and Lucile Packard Foundation, the Centre for International Forestry Research (CIFOR), and Gabonâs National Parks Agency (ANPN). This paper was supported by ForestPlots.net approved Research Project 81, âComparative Ecology of African Tropical Forestsâ. The development of ForestPlots.net and data curation has been funded by several grants, including NE/B503384/1, NE/N012542/1, ERC Advanced Grant 291585ââT-FORCESâ, NE/F005806/1, NERC New Investigators Awards, the Gordon and Betty Moore Foundation, a Royal Society University Research Fellowship and a Leverhulme Trust Research Fellowship. Fieldwork in the Democratic Republic of the Congo (Yangambi and Yoko sites) was funded by the Belgian Science Policy Office BELSPO (SD/AR/01A/COBIMFO, BR/132/A1/AFRIFORD, BR/143/A3/HERBAXYLAREDD, FED-tWIN2019-prf-075/CongoFORCE, EF/211/TREE4FLUX); by the Flemish Interuniversity Council VLIR-UOS (CD2018TEA459A103, FORMONCO II); by LâAcadĂŠmie de recherche et dâenseignement supĂŠrieur ARES (AFORCO project) and by the European Union through the FORETS project (Formation, Recherche, Environnement dans la TShopo) supported by the XIth European Development Fund. EMV was supported by fellowship from the CNPq (Grant 308543/2021-1). RAPELD plots in Brazil were supported by the Program for Biodiversity Research (PPBio) and the National Institute for Amazonian Biodiversity (INCT-CENBAM). BGL post-doc grant no. 2019/03379-4, SĂŁo Paulo Research Foundation (FAPESP). D.A.C. was supported by the CCI Collaborative fund. Plots in Mato Grosso, Brazil, were supported by the National Council for Scientific and Technological Development (CNPq), PELD-TRAN 441244/2016-5 and 441572/2020-0, and Mato Grosso State Research Support Foundation (FAPEMAT)â0346321/2021. We thank E. Chezeaux, R. Condit, W. J. Eggeling, R. M. Ewers, O. J. Hardy, P. Jeanmart, K. L. Khoon, J. L. Lloyd, A. Marjokorpi, W. Marthy, H. Ntahobavuka, D. Paget, J. T. A. Proctor, R. P. SalomĂŁo, P. Saner, S. Tan, C. O. Webb, H. Woell and N. Zweifel for contributing forest inventory data. We thank numerous field assistants for their invaluable contributions to the collection of forest inventory data, including A. Nkwasibwe, ITFC field assistant.Peer reviewe
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
Search for New Physics with Jets and Missing Transverse Momentum in pp collisions at sqrt(s) = 7 TeV
A search for new physics is presented based on an event signature of at least
three jets accompanied by large missing transverse momentum, using a data
sample corresponding to an integrated luminosity of 36 inverse picobarns
collected in proton--proton collisions at sqrt(s)=7 TeV with the CMS detector
at the LHC. No excess of events is observed above the expected standard model
backgrounds, which are all estimated from the data. Exclusion limits are
presented for the constrained minimal supersymmetric extension of the standard
model. Cross section limits are also presented using simplified models with new
particles decaying to an undetected particle and one or two jets
Search for anomalous t t-bar production in the highly-boosted all-hadronic final state
A search is presented for a massive particle, generically referred to as a
Z', decaying into a t t-bar pair. The search focuses on Z' resonances that are
sufficiently massive to produce highly Lorentz-boosted top quarks, which yield
collimated decay products that are partially or fully merged into single jets.
The analysis uses new methods to analyze jet substructure, providing
suppression of the non-top multijet backgrounds. The analysis is based on a
data sample of proton-proton collisions at a center-of-mass energy of 7 TeV,
corresponding to an integrated luminosity of 5 inverse femtobarns. Upper limits
in the range of 1 pb are set on the product of the production cross section and
branching fraction for a topcolor Z' modeled for several widths, as well as for
a Randall--Sundrum Kaluza--Klein gluon. In addition, the results constrain any
enhancement in t t-bar production beyond expectations of the standard model for
t t-bar invariant masses larger than 1 TeV.Comment: Submitted to the Journal of High Energy Physics; this version
includes a minor typo correction that will be submitted as an erratu
Measurement of the Z/gamma* + b-jet cross section in pp collisions at 7 TeV
The production of b jets in association with a Z/gamma* boson is studied
using proton-proton collisions delivered by the LHC at a centre-of-mass energy
of 7 TeV and recorded by the CMS detector. The inclusive cross section for
Z/gamma* + b-jet production is measured in a sample corresponding to an
integrated luminosity of 2.2 inverse femtobarns. The Z/gamma* + b-jet cross
section with Z/gamma* to ll (where ll = ee or mu mu) for events with the
invariant mass 60 < M(ll) < 120 GeV, at least one b jet at the hadron level
with pT > 25 GeV and abs(eta) < 2.1, and a separation between the leptons and
the jets of Delta R > 0.5 is found to be 5.84 +/- 0.08 (stat.) +/- 0.72 (syst.)
+(0.25)/-(0.55) (theory) pb. The kinematic properties of the events are also
studied and found to be in agreement with the predictions made by the MadGraph
event generator with the parton shower and the hadronisation performed by
PYTHIA.Comment: Submitted to the Journal of High Energy Physic
Azimuthal anisotropy of charged particles at high transverse momenta in PbPb collisions at sqrt(s[NN]) = 2.76 TeV
The azimuthal anisotropy of charged particles in PbPb collisions at
nucleon-nucleon center-of-mass energy of 2.76 TeV is measured with the CMS
detector at the LHC over an extended transverse momentum (pt) range up to
approximately 60 GeV. The data cover both the low-pt region associated with
hydrodynamic flow phenomena and the high-pt region where the anisotropies may
reflect the path-length dependence of parton energy loss in the created medium.
The anisotropy parameter (v2) of the particles is extracted by correlating
charged tracks with respect to the event-plane reconstructed by using the
energy deposited in forward-angle calorimeters. For the six bins of collision
centrality studied, spanning the range of 0-60% most-central events, the
observed v2 values are found to first increase with pt, reaching a maximum
around pt = 3 GeV, and then to gradually decrease to almost zero, with the
decline persisting up to at least pt = 40 GeV over the full centrality range
measured.Comment: Replaced with published version. Added journal reference and DO
- âŚ