2,040 research outputs found
Pedagogy subjects in the formation and in the construction of representations about teachers' work: views of preservice Chemistry and Physics teachers
Este estudo tem como objetivo analisar as concepções de licenciandos em Química e em Física sobre a prática profissional e as marcas deixadas pelas disciplinas pedagógicas na sua formação, assim como identificar sinais de mudanças em suas concepções durante a realização do curso de Licenciatura. Para tanto, textos foram produzidos por 54 alunos matriculados em cursos de Licenciatura de duas universidades públicas do estado de São Paulo, nos quais os licenciandos expressaram suas experiências de formação e apontaram elementos que consideram que terão alguma influência em sua atuação profissional. Os textos revelaram que as ideias que os licenciandos carregam são consistentes com muitas das visões e objetivos apresentados em cursos de formação de professores. Nas produções dos estudantes faz-se presente o desejo de compartilhar e promover em seus futuros alunos o interesse pela Química e a Física. Os seus comentários refletiram visões de professores que tiveram no passado, os quais gostariam de imitar, e de outros que não gostariam de ser. Os comentários também tornaram evidente a vontade dos licenciandos em se estabelecerem como professores que se preocupam com seus alunos. Os textos foram analisados segundo a Análise do Discurso de linha francesa, como tem sido divulgada por Eni Orlandi, especialmente a noção de formação discursiva.The objective of this study is to analyze the views of preservice chemistry and physics teachers about the professional practice and the influence of pedagogic disciplines on their formation. Furthermore, it aims at identifying changes in preservice teachers' opinions and beliefs throughout their education. Hence, texts were produced by 54 undergraduate students who were undertaking preservice courses in two public universities in the state of São Paulo, in which they expressed their experiences throughout the course and mentioned relevant aspects about their professional development. The texts revealed that their ideas were consistent concerning many of the views and goals of teacher preparation courses. Their statements reflected desires to share and stimulate interest for chemistry and physics in their future students. Their comments evidenced past experiences they would like to emulate and others they would rather not. They also expressed their worries about becoming teachers who do care for their students. The texts were analyzed by Discourse Analysis, in its French approach, according to Eni Orlandi, especially the concept of discursive formation
Feohifomicosis Producida por Alternaria Infectoria con Presentación Clínica de Múltiples Lesiones Vegetantes en un Paciente Sometido a un Trasplante Renal
The genus Alternaria is one of the most common black moulds and appears to be increasing as a causative agent of subcutaneous phaeohyphomycosis, particularly among immunosuppressed patients. A 53-year-old patient who had received a kidney transplant presented with multiple verrucous lesions on the distal extremities. Positive histopathology and cultures, in addition to rDNA ITS region sequencing, identified the fungal isolate as Alternaria infectoria. Oral itraconazole was administered for 10 months. A follow-up at 15 months demonstrated no signs of infection. Clinical manifestations of cutaneous alternariosis vary significantly and only a few cases have been described in the literature. Although optimal treatment options remain controversial, this case of phaeohyphomycosis was successfully treated with itraconazole monotherapy
Massively parallel computing on an organic molecular layer
Current computers operate at enormous speeds of ~10^13 bits/s, but their
principle of sequential logic operation has remained unchanged since the 1950s.
Though our brain is much slower on a per-neuron base (~10^3 firings/s), it is
capable of remarkable decision-making based on the collective operations of
millions of neurons at a time in ever-evolving neural circuitry. Here we use
molecular switches to build an assembly where each molecule communicates-like
neurons-with many neighbors simultaneously. The assembly's ability to
reconfigure itself spontaneously for a new problem allows us to realize
conventional computing constructs like logic gates and Voronoi decompositions,
as well as to reproduce two natural phenomena: heat diffusion and the mutation
of normal cells to cancer cells. This is a shift from the current static
computing paradigm of serial bit-processing to a regime in which a large number
of bits are processed in parallel in dynamically changing hardware.Comment: 25 pages, 6 figure
Enzymatic degradation of starch thermoplastic blends using samples of different thickness
The material studied was a thermoplastic blend of corn starch with a poly(ethylene-vinyl alcohol) copolymer, SEVA-C. The influence of both the material’s exposed surface and enzyme concentration on degradation kinetics was studied. As α-amylase is present in the blood plasma, experiments were performed, varying the material thickness and the α-amylase between 50 and 100 units/l, at 37°C, lasting up to 90 days. Four different batches using SEVA-C and starch samples of different thickness were performed. The positive correlation between degradation rate and the exposed material surface was confirmed, since thin films with larger exposed surfaces were degraded faster than thick square plates having the same total mass. The degradation extent depends on the total amount of amorphous starch present in the formulation rather than on the amount of enzyme used and the minimum thickness to ensure maximum degradation was estimated to be close to 0.25 mm
Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector
Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02 TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1 μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos2Δϕ modulation for all ΣETPb ranges and particle pT
Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at s√=8 TeV with the ATLAS detector
The results of a search for direct pair production of the scalar partner to the top quark using an integrated luminosity of 20.1fb−1 of proton–proton collision data at √s = 8 TeV recorded with the ATLAS detector at the LHC are reported. The top squark is assumed to decay via t˜→tχ˜01 or t˜→ bχ˜±1 →bW(∗)χ˜01 , where χ˜01 (χ˜±1 ) denotes the lightest neutralino (chargino) in supersymmetric models. The search targets a fully-hadronic final state in events with four or more jets and large missing transverse momentum. No significant excess over the Standard Model background prediction is observed, and exclusion limits are reported in terms of the top squark and neutralino masses and as a function of the branching fraction of t˜ → tχ˜01 . For a branching fraction of 100%, top squark masses in the range 270–645 GeV are excluded for χ˜01 masses below 30 GeV. For a branching fraction of 50% to either t˜ → tχ˜01 or t˜ → bχ˜±1 , and assuming the χ˜±1 mass to be twice the χ˜01 mass, top squark masses in the range 250–550 GeV are excluded for χ˜01 masses below 60 GeV
Widespread environmental contamination with Mycobacterium tuberculosis complex revealed by a molecular detection protocol
Environmental contamination with Mycobacterium tuberculosis complex (MTC) has been considered crucial for bovine tuberculosis persistence in multi-host-pathogen systems. However, MTC contamination has been difficult to detect due to methodological issues. In an attempt to overcome this limitation we developed an improved protocol for the detection of MTC DNA. MTC DNA concentration was estimated by the Most Probable Number (MPN) method. Making use of this protocol we showed that MTC contamination is widespread in different types of environmental samples from the Iberian Peninsula, which supports indirect transmission as a contributing mechanism for the maintenance of bovine tuberculosis in this multi-host-pathogen system. The proportion of MTC DNA positive samples was higher in the bovine tuberculosis-infected than in presumed negative area (0.32 and 0.18, respectively). Detection varied with the type of environmental sample and was more frequent in sediment from dams and less frequent in water also from dams (0.22 and 0.05, respectively). The proportion of MTC-positive samples was significantly higher in spring (p<0.001), but MTC DNA concentration per sample was higher in autumn and lower in summer. The average MTC DNA concentration in positive samples was 0.82 MPN/g (CI95 0.70-0.98 MPN/g). We were further able to amplify a DNA sequence specific of Mycobacterium bovis/caprae in 4 environmental samples from the bTB-infected area
Controle social: uma perspectiva sobre conselhos de direito, em específico, o Conselho da Criança e do Adolescente
A execução do Projeto de Intervenção debruçou-se sobre a problemática em torno do conceito sobre Conselhos de Direito da Criança e do Adolescente, através do Controle Social. Uma das metodologias do projeto de extensão Assessoramento Técnico aos Representantes Da Ria – Rede De Instituições De Acolhimento A Crianças E Adolescentes da Grande Curitiba-PR são as constantes reuniões para identificar as demandas que são levantadas pelos técnicos que compõe a RIA. Os objetivos propostos permeiram a promoção de um evento para publicizar informações acerca do tema em questão. A metodologia utilizada foi adaptada de acordo com o contexto social, neste caso, a pandemia e o isolamento social. Foi necessário um evento via Facebook para viabilizar a proposta da publicização sobre os conceitos de controle social. Após o evento, um questionário para avaliação do evento foi enviado. O evento obteve uma análise positiva acerca da necessidade de levantar debates sobre o tema proposto.
Palavras-chave: Controle social. Participação democrática. Conselho da Criança e do Adolescente. Conselho de Direito e Participação Popular
VDES J2325-5229 a z=2.7 gravitationally lensed quasar discovered using morphology independent supervised machine learning
We present the discovery and preliminary characterization of a gravitationally lensed quasar with a source redshift = 2.74 and image separation of 2.9 arcsec lensed by a foreground = 0.40 elliptical galaxy. Since optical observations of gravitationally lensed quasars show the lens system as a superposition of multiple point sources and a foreground lensing galaxy, we have developed a morphology-independent multi-wavelength approach to the photometric selection of lensed quasar candidates based on Gaussian Mixture Models (GMM) supervised machine learning. Using this technique and multicolour photometric observations from the Dark Energy Survey (DES), near-IR photometry from the VISTA Hemisphere Survey (VHS) and WISE mid-IR photometry, we have identified a candidate system with two catalogue components with = 18.61 and = 20.44 comprising an elliptical galaxy and two blue point sources. Spectroscopic follow-up with NTT and the use of an archival AAT spectrum show that the point sources can be identified as a lensed quasar with an emission line redshift of = 2.739 ± 0.003 and a foreground early-type galaxy with = 0.400 ± 0.002. We model the system as a single isothermal ellipsoid and find the Einstein radius θE ∼ 1.47 arcsec, enclosed mass enc ∼ 4 × 10⊙ and a time delay of ∼52 d. The relatively wide separation, month scale time delay duration and high redshift make this an ideal system for constraining the expansion rate beyond a redshift of 1.FO is supported jointly by CAPES (the Science without Borders programme) and the Cambridge Commonwealth Trust. RGM, CAL, MWA, MB, SLR acknowledge the support of UK Science and Technology Research Council (STFC). AJC acknowledges the support of a Raymond and Beverly Sackler visiting fellowship at the Institute of Astronomy.
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