135 research outputs found
AVALIAÇÃO DE CRITÉRIOS DE HETEROGENEIDADE BASEADOS EM ATRIBUTOS MORFOLÓGICOS PARA SEGMENTAÇÃO DE IMAGENS POR CRESCIMENTO DE REGIÕES
Avalia-se neste trabalho o impacto de se considerar atributos morfológicos na formulação do critério que governa o crescimento de regiões na segmentação de imagens. Para tanto, uma extensão do algoritmo de segmentação multiresolução proposto por Baatz e Schäpe (2000) foi proposta e implementada, permitindo que se testassem critérios derivados de diferentes atributos morfológicos. O estudo valeu-se de um método supervisionado para medir numericamente a qualidade da segmentação. O resultado ideal da segmentação foi representado por um conjunto de segmentos de referência delineados manualmente para três recortes de imagens Quickbird-2. Para cada critério testado, os valores ótimos para os parâmetros do algoritmo de segmentação foram determinados por um processo estocástico que procurou minimizar a discrepância entre as referências e o resultado de cada segmentação. Uma análise tanto quantitativa quanto qualitativa dos resultados indicou inequivocamente que a inclusão de atributos morfológicos no critério de heterogeneidade, que decide a fusão entre segmentos adjacentes no processo de crescimento de regiões, pode resultar numa substancial melhoria da qualidade da segmentação. O artigo realça ainda a importância de se adotar atributos morfológicos apropriados para cada classe de objetos e tece considerações que orientam a escolha destes atributos
EFEITOS DAS INTERVENÇÕES VERBAIS REALIZADAS PELO TREINADOR DURANTE JOGOS REDUZIDOS SOBRE O DESEMPENHO TÁTICO DE JOVENS JOGADORES DE FUTEBOL
The aim of this study was to verify the effects of verbal interventions performed by the coach on the tactical performance of young soccer players. 24 under-13 players and a coach with more than 10 years of experience participated in this study. Players were submitted to two conditions: experimental (small-sided games with verbal intervention) and control (small-sdeid games without verbal intervention). The players, in both conditions, played small-sided games in the format Goalkeeper+3 vs. 3+Goalkeeper, lasting 4 minutes. Tactical performance was analyzed using the Football Tactical Assessment System (FUT-SAT), considering the 10 fundamental tactical principles. The categorization of verbal interventions performed by the coach was performed through content analysis. The results show that the verbal interventions used (~90% instructive/direct) positively influenced the defensive tactical performance, however, they had a negative impact on the offensive tactical performance. It is concluded that the coach's verbal interventions can be important pedagogical tools to guide the tactical performance of young players. However, the predominance of direct instructions can compromise the offensive tactical performance during small-sided games in young players. Coaches, therefore, should reflect on how and in what ways to communicate with their players, in an attempt to promote a more representative learning environment.El objetivo de este estudio fue verificar los efectos de las intervenciones verbales realizadas por el entrenador en el desempeño táctico de jóvenes futbolistas. En este estudio participaron 24 jugadores menores de 13 años y un entrenador con más de 10 años de experiencia. Los jugadores fueron sometidos a dos condiciones: experimental (juegos reducidos con intervención verbal) y control (juegos reducidos sin intervención verbal). Los jugadores, en ambas condiciones, jugaron partidos reducidos en el formato Portero+3 vs. 3+Portero, con una duración de 4 minutos. El desempeño táctico se analizó mediante el Sistema de Evaluación Táctica del Fútbol (FUT-SAT), considerando los 10 principios tácticos fundamentales. La categorización de las intervenciones verbales realizadas por el entrenador se realizó a través del análisis de contenido. Los resultados muestran que las intervenciones verbales utilizadas (~90% instructivas/directas) influyeron positivamente en el desempeño táctico defensivo, sin embargo, tuvieron un impacto negativo en el desempeño táctico ofensivo. Se concluye que las intervenciones verbales del entrenador pueden ser importantes herramientas pedagógicas para orientar el desempeño táctico de los jóvenes jugadores. Sin embargo, el predominio de las instrucciones directas puede comprometer el desempeño táctico ofensivo durante juegos reducidos en jugadores jóvenes. Los entrenadores, por lo tanto, deberían reflexionar sobre cómo y de qué manera comunicarse con sus jugadores, en un intento de promover un entorno de aprendizaje más representativo.O objetivo deste estudo foi verificar os efeitos das intervenções verbais realizadas pelo treinador sobre o desempenho tático de jovens jogadores de futebol. Participaram deste estudo 24 jogadores da categoria sub-13 e um treinador, com mais de 10 anos de experiência. Os jogadores foram submetidos a duas condições: experimental (jogos reduzidos com intervenção verbal) e controle (jogos reduzidos sem intervenção verbal). Os jogadores, em ambas as condições, realizaram jogos reduzidos no formato Goleiro+3 vs. 3+Goleiro, com duração de 4 minutos. O desempenho tático foi analisado por meio do Sistema de Avaliação Tática no Futebol (FUT-SAT), considerando os 10 princípios táticos fundamentais. A categorização das intervenções verbais realizadas pelo treinador foi realizada por meio da análise de conteúdo. Os resultados mostram que as intervenções verbais utilizadas (~90% instrutivos/diretos) influenciaram positivamente no desempenho tático defensivo, porém, exerceram impacto negativo no desempenho tático ofensivo. Conclui-se que intervenções verbais do treinador podem se constituir ferramentas pedagógicas importantes para orientar o desempenho tático de jovens jogadores. Contudo, a predominância de instruções diretas pode comprometer o desempenho tático ofensivo durante jogos reduzidos em jovens jogadores. Os treinadores, portanto, devem refletir sobre como e de que forma se comunicar com seus jogadores, na tentativa de promover um ambiente de aprendizagem mais representativo
Incentivo a criação de uma consciência universitária em alunos do ensino médio de escolas públicas brasileiras
Anais do II Seminário Seminário Estadual PIBID do Paraná: tecendo saberes / organizado por Dulcyene Maria Ribeiro e Catarina Costa Fernandes — Foz do Iguaçu: Unioeste; Unila, 2014Observando o atual cenário da educação brasileira, nota-se facilmente que existem
problemas muito latentes em relação à estrutura e qualidade de ensino. Porém, um fator que é citado
com menor frequência é a questão cultural que envolve todo o processo de ensino-aprendizagem.
Logo que é de conhecimento de todos que a cultura brasileira não é voltada, tanto quanto deveria, para
o estudo. Este projeto vem com o objetivo de contextualizar o “Por que de estudar”. Com propostas
práticas em relação à vida profissional do discente. Mostrando-o que, ao estudar, ao se interessar pelo
ensino superior, várias outras oportunidades mais avantajadas financeiramente podem surgir.
Explanando em aulas expositivas quais são seus direitos e que a Universidade não está tão distante
quanto parec
Large diatom bloom off the Antarctic Peninsula during cool conditions associated with the 2015/2016 El Niño
Diatoms play crucial functions in trophic structure and biogeochemical cycles. Due to poleward warming, there has been a substantial decrease in diatom biomass, especially in Antarctic regions that experience strong physical changes. Here we analyze the phytoplankton contents of water samples collected in the spring/summer of 2015/2016 off the North Antarctic Peninsula during the extreme El Niño event and compare them with corresponding satellite chlorophyll-a data. The results suggest a close link between large diatom blooms, upper ocean physical structures and sea ice cover, as a consequence of the El Niño effects. We observed massive concentrations (up to 40 mg m–3 of in situ chlorophyll-a) of diatoms coupled with substantially colder atmospheric and oceanic temperatures and high mean salinity values associated with a lower input of meltwater. We hypothesize that increased meltwater concentration due to continued atmospheric and oceanic warming trends will lead to diatom blooms becoming more episodic and spatially/temporally restricted
Changes in phytoplankton communities along the Northern Antarctic Peninsula: Causes, impacts and research priorities
The Northern Antarctic Peninsula (NAP), located in West Antarctica, is amongst the most impacted regions by recent warming events. Its vulnerability to climate change has already led to an accumulation of severe changes along its ecosystems. This work reviews the current findings on impacts observed in phytoplankton communities occurring in the NAP, with a focus on its causes, consequences, and the potential research priorities toward an integrated comprehension of the physical–biological coupling and climate perspective. Evident changes in phytoplankton biomass, community composition and size structure, as well as potential bottom-up impacts to the ecosystem are discussed. Surface wind, sea ice and meltwater dynamics, as key drivers of the upper layer structure, are identified as the leading factors shaping phytoplankton. Short- and long-term scenarios are suggested for phytoplankton communities in the NAP, both indicating a future increase of the importance of small flagellates at the expense of diatoms, with potential devastating impacts for the ecosystem. Five main research gaps in the current understanding of the phytoplankton response to climate change in the region are identified: (i) anthropogenic signal has yet to be disentangled from natural climate variability; (ii) the influence of small-scale ocean circulation processes on phytoplankton is poorly understood; (iii) the potential consequences to regional food webs must be clarified; (iv) the magnitude and risk of potential changes in phytoplankton composition is relatively unknown; and (v) a better understanding of phytoplankton physiological responses to changes in the environmental conditions is required. Future research directions, along with specific suggestions on how to follow them, are equally suggested. Overall, while the current knowledge has shed light on the response of phytoplankton to climate change, in order to truly comprehend and predict changes in phytoplankton communities, there must be a robust collaboration effort integrating both Antarctic research programs and the whole scientific community under a common research framework
Uso de antimicrobiano nanoparticulado para o tratamento da mastite subcl?nica de ovelhas de corte no per?odo seco.
A inflama??o da gl?ndula mam?ria ? uma das
principais causas de preju?zo na ovinocultura. Este estudo
teve como objetivo investigar as taxas de cura do tratamento
da mastite subcl?nica ap?s infus?o intramam?ria de princ?pio
ativo antimicrobiano no momento da secagem, em formula??es
convencional e nanoparticulada. Os rebanhos estavam
localizados em S?o Carlos, S?o Paulo, Brasil. Analisou-se um
total de 584 gl?ndulas mam?rias de 307 ovelhas de aptid?o
para produ??o de carne. Triagem pr?via dos casos subcl?nicos
de mastite foi efetuada por meio do California Mastitis
Test (CMT) e/ou da contagem de c?lulas som?ticas (CCS).
An?lises microbiol?gicas foram realizadas para confirma??o
da etiologia infecciosa. As gl?ndulas mam?rias com mastite
subcl?nica foram distribu?das em tr?s grupos: G1 (Controle;
gl?ndulas mam?rias que n?o receberam tratamento antimicrobiano);
G2 (gl?ndulas mam?rias em que foi administrado
100 mg de cloxacilina benzatina em estrutura convencional)
e G3 (gl?ndulas mam?rias em que foi administrado 50 mg de cloxacilina benzatina em estrutura nanoencapsulada). O tratamento
aplicado ao G3 mostrou-se mais eficiente (P=0,047)
na cura de gl?ndulas mam?rias com mastite subcl?nica. O uso
da cloxacilina nanoencapsulada no momento da secagem de
ovelhas de corte auxilia no controle da mastite subcl?nica infecciosa
e reduz os preju?zos consequentes.Inflammation of the mammary gland is one of the main causes of losses in sheep-rearing.
This study aimed to investigate the cure rates from treating subclinical mastitis after intramammary
infusion of active antimicrobial agents as conventional formulations or as nanoparticles,
at the time when the ewes are being dried off. A total of 584 mammary glands in
307 ewes in meat-producing herds located in S?o Carlos, S?o Paulo, Brazil, were analyzed.
Prescreening of subclinical mastitis cases was done using the California mastitis test (CMT)
and/or the somatic cell count (SCC). Microbiological analyses were performed to confirm
the infectious etiology. The mammary glands with subclinical mastitis were distributed
into three groups: G1 (control; mammary glands that did not receive any antimicrobial treatment);
G2 (mammary glands to which 100mg of benzathine cloxacillin in conventional
form were administered); and G3 (mammary glands to which 50mg of benzathine cloxacillin
in nanoparticulate form were administered). The treatment applied to G3 was more
efficient (P=0.047) in curing mammary glands with subclinical mastitis. Use of cloxacillin
nanoparticles at the time when the ewes are being dried off helps to control infectious subclinical
mastitis and reduces consequential losses among meat-producing herds
Combined fit to the spectrum and composition data measured by the Pierre Auger Observatory including magnetic horizon effects
The measurements by the Pierre Auger Observatory of the energy spectrum and mass composition of cosmic rays can be interpreted assuming the presence of two extragalactic source populations, one dominating the flux at energies above a few EeV and the other below. To fit the data ignoring magnetic field effects, the high-energy population needs to accelerate a mixture of nuclei with very hard spectra, at odds with the approximate E shape expected from diffusive shock acceleration. The presence of turbulent extragalactic magnetic fields in the region between the closest sources and the Earth can significantly modify the observed CR spectrum with respect to that emitted by the sources, reducing the flux of low-rigidity particles that reach the Earth. We here take into account this magnetic horizon effect in the combined fit of the spectrum and shower depth distributions, exploring the possibility that a spectrum for the high-energy population sources with a shape closer to E be able to explain the observations
Measuring the muon content of inclined air showers using AERA and the water-Cherenkov detector array of the Pierre Auger Observatory
Studies of the mass composition of cosmic rays and proton-proton interaction cross-sections at ultra-high energies with the Pierre Auger Observatory
In this work, we present an estimate of the cosmic-ray mass composition from the distributions of the depth of the shower maximum (Xmax) measured by the fluorescence detector of the Pierre Auger Observatory. We discuss the sensitivity of the mass composition measurements to the uncertainties in the properties of the hadronic interactions, particularly in the predictions of the particle interaction cross-sections. For this purpose, we adjust the fractions of cosmic-ray mass groups to fit the data with Xmax distributions from air shower simulations. We modify the proton-proton cross-sections at ultra-high energies, and the corresponding air shower simulations with rescaled nucleus-air cross-sections are obtained via Glauber theory. We compare the energy-dependent composition of ultra-high-energy cosmic rays obtained for the different extrapolations of the proton-proton cross-sections from low-energy accelerator data
Study of downward Terrestrial Gamma-ray Flashes with the surface detector of the Pierre Auger Observatory
The surface detector (SD) of the Pierre Auger Observatory, consisting of 1660 water-Cherenkov detectors (WCDs), covers 3000 km2 in the Argentinian pampa. Thanks to the high efficiency of WCDs in detecting gamma rays, it represents a unique instrument for studying downward Terrestrial Gamma-ray Flashes (TGFs) over a large area. Peculiar events, likely related to downward TGFs, were detected at the Auger Observatory. Their experimental signature and time evolution are very different from those of a shower produced by an ultrahigh-energy cosmic ray. They happen in coincidence with low thunderclouds and lightning, and their large deposited energy at the ground is compatible with that of a standard downward TGF with the source a few kilometers above the ground. A new trigger algorithm to increase the TGF-like event statistics was installed in the whole array. The study of the performance of the new trigger system during the lightning season is ongoing and will provide a handle to develop improved algorithms to implement in the Auger upgraded electronic boards. The available data sample, even if small, can give important clues about the TGF production models, in particular, the shape of WCD signals. Moreover, the SD allows us to observe more than one point in the TGF beam, providing information on the emission angle
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