175 research outputs found
Desenvolvimento de recursos didácticos informatizados no âmbito da educação para o desenvolvimento sustentável. o exemplo do courseware SeRe
A falta de recursos didácticos informatizados de qualidade para o 1º e 2º Ciclos do Ensino Básico (1º/2º CEB), concebidos no âmbito da Educação para o Desenvolvimento Sustentável (EDS), numa perspectiva de Ensino por Pesquisa, determinou a organização de uma equipa multidisciplinar para o desenvolvimento do «Courseware Sere - O Ser Humano e os Recursos Naturais». Ajustando alguns princípios de desenvolvimento de software, particularmente de Design Centrado no Utilizador (DCU), o trabalho da equipa multidisciplinar, constituída por elementos com diversas competências (ao nível da Didáctica das Ciências, da Tecnologia Educativa, de Design e de Programação), centrou-se no desenvolvimento de um recurso didáctico informatizado que integra várias tipologias de software, nomeadamente simulações e visualizações, com as actividades didácticas. A orientação do recurso, as temáticas propostas e as metodologias e estratégias de exploração privilegiadas fundamentam-se: i) na identificação das orientações nacionais e internacionais da EDS; ii) na identificação das necessidades e interesses dos professores quanto à implementação de actividades com orientação EDS (Sá, 2008; Sá e Martins, 2007), iii) no paradigma de ensino por competências (Cachapuz, Sá-Chaves e Paixão, 2004) e iv) no recurso a um design interactivo centrado no utilizador (Costa, Loureiro, Reis, Sá, Guerra e Vieira, 2009; Guerra, 2007). Neste artigo faz-se uma apresentação do processo de desenvolvimento do recurso didáctico, das temáticas propostas e das metodologias e estratégias de exploração perspectivadas pelos autores do recurs
An EST-based analysis identifies new genes and reveals distinctive gene expression features of Coffea arabica and Coffea canephora
Background: Coffee is one of the world’s most important crops; it is consumed worldwide and plays a significant
role in the economy of producing countries. Coffea arabica and C. canephora are responsible for 70 and 30% of
commercial production, respectively. C. arabica is an allotetraploid from a recent hybridization of the diploid
species, C. canephora and C. eugenioides. C. arabica has lower genetic diversity and results in a higher quality
beverage than C. canephora. Research initiatives have been launched to produce genomic and transcriptomic data
about Coffea spp. as a strategy to improve breeding efficiency.
Results: Assembling the expressed sequence tags (ESTs) of C. arabica and C. canephora produced by the
Brazilian Coffee Genome Project and the Nestlé-Cornell Consortium revealed 32,007 clusters of C. arabica and
16,665 clusters of C. canephora. We detected different GC3 profiles between these species that are related to
their genome structure and mating system. BLAST analysis revealed similarities between coffee and grape (Vitis
vinifera) genes. Using KA/KS analysis, we identified coffee genes under purifying and positive selection. Protein
domain and gene ontology analyses suggested differences between Coffea spp. data, mainly in relation to
complex sugar synthases and nucleotide binding proteins. OrthoMCL was used to identify specific and prevalent
coffee protein families when compared to five other plant species. Among the interesting families annotated
are new cystatins, glycine-rich proteins and RALF-like peptides. Hierarchical clustering was used to
independently group C. arabica and C. canephora expression clusters according to expression data extracted
from EST libraries, resulting in the identification of differentially expressed genes. Based on these results, we
emphasize gene annotation and discuss plant defenses, abiotic stress and cup quality-related functional
categories.
Conclusion: We present the first comprehensive genome-wide transcript profile study of C. arabica and C.
canephora, which can be freely assessed by the scientific community at http://www.lge.ibi.unicamp.br/
coffea. Our data reveal the presence of species-specific/prevalent genes in coffee that may help to explain
particular characteristics of these two crops. The identification of differentially expressed transcripts offers a
starting point for the correlation between gene expression profiles and Coffea spp. developmental traits,
providing valuable insights for coffee breeding and biotechnology, especially concerning sugar metabolism
and stress tolerance
Avalanches in the Weakly Driven Frenkel-Kontorova Model
A damped chain of particles with harmonic nearest-neighbor interactions in a
spatially periodic, piecewise harmonic potential (Frenkel-Kontorova model) is
studied numerically. One end of the chain is pulled slowly which acts as a weak
driving mechanism. The numerical study was performed in the limit of infinitely
weak driving. The model exhibits avalanches starting at the pulled end of the
chain. The dynamics of the avalanches and their size and strength distributions
are studied in detail. The behavior depends on the value of the damping
constant. For moderate values a erratic sequence of avalanches of all sizes
occurs. The avalanche distributions are power-laws which is a key feature of
self-organized criticality (SOC). It will be shown that the system selects a
state where perturbations are just able to propagate through the whole system.
For strong damping a regular behavior occurs where a sequence of states
reappears periodically but shifted by an integer multiple of the period of the
external potential. There is a broad transition regime between regular and
irregular behavior, which is characterized by multistability between regular
and irregular behavior. The avalanches are build up by sound waves and shock
waves. Shock waves can turn their direction of propagation, or they can split
into two pulses propagating in opposite directions leading to transient
spatio-temporal chaos. PACS numbers: 05.70.Ln,05.50.+q,46.10.+zComment: 33 pages (RevTex), 15 Figures (available on request), appears in
Phys. Rev.
Alterations In The Achilles Tendon After Inflammation In Surrounding Tissue
Objective: To analyze the characteristics of the Achilles tendon of rats after induction of localized inflammation in the rat paw. Methods: In our study three groups were used: inflamed group with carrageenan in rat paw (G1); saline group (G2) and control group (G3). After 4 hours the animals were euthanized and the Achilles tendon removed. Results: No significant differences were observed in the analysis of non-collagenous proteins, glycosaminoglycans and hydroxyproline in the groups but a tendency of reduction was verified in G1. As regards the organization of collagen molecules, no differences were observed between groups. With respect to MMPs activity, a stronger presence of the active isoform of MMP-2 in G1 was observed, suggesting that the remodeling was occurring. Conclusion: Thus, we conclude that the inflammatory process in rat paw may affect the remodeling of tendons located near the inflamed site.205266269Maffulli, N., Kader, D., Tendinopathy of tendo Achillis (2002) J Bone Joint Surg Br, 84 (1), pp. 1-8Maffulli, N., Rupture of the Achilles tendon (1999) J Bone Joint Surg Am, 81 (7), pp. 1019-1036Järvinen, T.A., Kannus, P., Maffulli, N., Khan, K.M., Achilles tendon disorders: etiology and epidemiology (2005) Foot Ankle Clin, 10 (2), pp. 255-266Oliveira, F.S., Pinfildi, C.E., Parizoto, N.A., Liebano, R.E., Bossini, P.S., Garcia, E.B., Effect of low level laser therapy (830 nm) with different therapyregimes on the process of tissue repair in partial lesion calcaneous tendon (2009) Lasers Surg Med, 41 (4), pp. 271-276Karousou, E., Ronga, M., Vigetti, D., Passi, A., Maffulli, N., Collagens, proteoglycans, MMP-2, MMP-9 and TIMPs in human Achilles tendon rupture (2008) Clin Orthop Relat Res, 466 (7), pp. 1577-1582Riley, G., Matrix metalloproteinase activities and their relationship with collagen remodelling in tendon pathology (2002) Matrix Biol, 21 (2), pp. 185-195Dario, B.E., Barquilha, G., Marques, R.M., Lesões esportivas: um estudo com atletas de basquetebol Bauruense (2010) Rev Bras Cienc Esporte, 31 (3), pp. 205-215Vieira, C.P., Aro, A.A., Almeida, M.S., de Mello, G.C., Antunes, E., Pimentel, E.R., Effects of acute inflammation induced in the rat paw on the deep digital flexor tendon (2012) Connect Tissue Res, 53 (2), pp. 160-168Tillander, B., Franzén, L.E., Nilsson, E., Norlin, R., Carrageenan-induced subacromial bursitis caused changes in the rat's rotator cuff (2001) J Orthop Res, 19 (3), pp. 441-447Winter, C.A., Risley, E.A., Nuss, G.W., Carrageenin-induced edema in hind paw of the rat as an assay for antiiflammatory drugs (1962) Proc Soc Exp Biol Med, 111, pp. 544-547Bradford, M.M., A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding (1976) Anal Biochem, 72, pp. 248-254Farndale, R.W., Buttle, D.J., Barrett, A.J., Improved quantitation and discrimination of sulphated glycosaminoglycans by use of dimethylmethylene blue (1986) Biochim Biophys Acta, 883 (2), pp. 173-177Marqueti, R.C., Parizotto, N.A., Chriguer, R.S., Perez, S.E., Selistre-de-Araujo, H.S.A., ndrogenic-anabolic steroids associated with mechanical loading inhibit matrix metallopeptidase activity and affect the remodeling of the achilles tendon in rats (2006) Am J Sports Med, 34 (8), pp. 1274-1280Vidal, B.C., Mello, M.L., Supramolecular order following binding of the dichroic birefringent sulfonic dye Ponceau SS to collagen fibers (2005) Biopolymers, 78 (3), pp. 121-128Riley, G., Tendinopathy:from basic science to treatment (2008) Nat Clin Pract Rheumatol, 4 (2), pp. 82-89Szabo, K.A., Ablin, R.J., Singhingh, G., Matrix metalloproteinases and the immune response (2004) Clin Appl Immun Rev, 4, pp. 295-319Chakraborti, S., Mandal, M., Das, S., Mandal, A., Chakraborti, T., Regulation of matrix metalloproteinases: an overview (2003) Mol Cell Biochem, 253 (1-2), pp. 269-285Magra, M., Maffulli, N., Matrix metalloproteases: a role in overuse tendinopathies (2005) Br J Sports Med, 39 (11), pp. 789-791Clutterbuck, A.L., Harris, P., Allaway, D., Mobasheri, A., Matrix metalloproteinases in inflammatory pathologies of the horse (2010) Vet J, 183 (1), pp. 27-38Marsolais, D., Duchesne, E., Côté, C.H., Frenette, J., Inflammatory cells do not decrease the ultimate tensile strength of intact tendons in vivo and in vitro: protective role of mechanical loading (2007) J Appl Physiol, 102 (1), pp. 11-1
Fluctuations and Dissipation of Coherent Magnetization
A quantum mechanical model is used to derive a generalized Landau-Lifshitz
equation for a magnetic moment, including fluctuations and dissipation. The
model reproduces the Gilbert-Brown form of the equation in the classical limit.
The magnetic moment is linearly coupled to a reservoir of bosonic degrees of
freedom. Use of generalized coherent states makes the semiclassical limit more
transparent within a path-integral formulation. A general
fluctuation-dissipation theorem is derived. The magnitude of the magnetic
moment also fluctuates beyond the Gaussian approximation. We discuss how the
approximate stochastic description of the thermal field follows from our
result. As an example, we go beyond the linear-response method and show how the
thermal fluctuations become anisotropy-dependent even in the uniaxial case.Comment: 22 page
Immunological and Immunogenetic Parameters on the Diversity of Ocular Toxoplasmosis: Evidence to Support Morphological Criteria to Classify Retinal/Retinochoroidal Scar Lesions in Epidemiologic Surveys
Uso da adubação orgânica e cobertura morta na cultura da calêndula (Calendula officinalis L.).
A calêndula representa fonte alternativa econômica principalmente para a agricultura familiar. O objetivo do presente trabalho foi avaliar os efeitos da adubação orgânica e do uso da cobertura morta sobre a produção de biomassa e teor de flavonóides totais em plantas de calêndula. O experimento foi realizado no Campus de Montes Claros da Universidade Federal de Minas Gerais, utilizando-se o delineamento em blocos casualizados em esquema fatorial 2x2x4 com quatro repetições: duas épocas de colheita, presença ou ausência de cobertura morta e quatro doses de composto orgânico (0, 30, 60 e 90 t ha-1). As maiores produções de biomassa e flavonóides totais foram verificadas com o aumento das doses de composto orgânico. Para os flavonóides totais o maior teor foi obtido na segunda colheita na presença de cobertura morta
Evaluation of inoculum potential of pathogens in seeds: relation to physiological quality and DNA quantification by qPCR
Application of isotope-selective non-dispersive infrared spectrometry for the evaluation of the 13C-urea breath test: comparison with three concordant methods
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