Uma proposta de classificação de analogias para o ensino nas ciências da saúde

O objetivo desse trabalho é contribuir para o processo de ensino de Ciências da Saúde por meio da apresentação de uma nova proposta de classificação de analogias contendo suas categorias, ca­racterizações e tipologias, elaborada a partir de duas dissertações de mestrado. Sua formulação ocorreu após análise de livros didáticos de Enfermagem e de Fisioterapia, de questionários e entrevistas com profissionais das áreas. A proposta contém oito categorias com respectivas caracterizações e apresenta uma tipologia própria, flexível de modo a ser reconstruída e se aplica a outras áreas do conhecimento. Os resultados apontam a necessidade de ampliar o sistema de classificação utilizado no ensino de ciên­cias de modo a contemplar as analogias encontradas no presente estudo

Crystallization and synchrotron X-ray diffraction studies of human interleukin-22

Human interleukin-22, a novel member of the cytokine family, has been crystallized in hanging drops using the vapour-diffusion technique. Preliminary X-ray diffraction experiments using synchrotron radiation reveal that the protein crystallizes in space group P2(1)2(1)2(1), with unit-cell parameters a = 55.44, b = 61.62, c = 73.43 Angstrom, and diffracts beyond 2.00 Angstrom resolution.58352953

Interaction of vortices in viscous planar flows

We consider the inviscid limit for the two-dimensional incompressible Navier-Stokes equation in the particular case where the initial flow is a finite collection of point vortices. We suppose that the initial positions and the circulations of the vortices do not depend on the viscosity parameter \nu, and we choose a time T > 0 such that the Helmholtz-Kirchhoff point vortex system is well-posed on the interval [0,T]. Under these assumptions, we prove that the solution of the Navier-Stokes equation converges, as \nu -> 0, to a superposition of Lamb-Oseen vortices whose centers evolve according to a viscous regularization of the point vortex system. Convergence holds uniformly in time, in a strong topology which allows to give an accurate description of the asymptotic profile of each individual vortex. In particular, we compute to leading order the deformations of the vortices due to mutual interactions. This allows to estimate the self-interactions, which play an important role in the convergence proof.Comment: 39 pages, 1 figur

Prevalence and determinants of chronic respiratory diseases in adults in rural Sudan

BACKGROUND: Chronic respiratory diseases (CRDs) greatly contribute to worldwide mortality. Despite new data emerging from Africa, prevalence estimates and determinants of CRDs in rural settings are limited. This study sought to extend the existing research conducted in urban Sudan by conducting a rural comparison. METHODS: Participants aged ≥18 years (n = 1,850), living in rural Gezira State completed pre-and post-bronchodilator spirometry and a questionnaire. Prevalence of respiratory symptoms and spirometric abnormalities were reported. Regression analyses were used to identify risk factors for CRDs. RESULTS: Prevalence of chronic airflow obstruction (CAO) was 4.1% overall and 5.5% in those aged ≥40 years. Reversibility was seen in 6.4%. Low forced vital capacity (FVC) was seen in 58.5%, and at least one respiratory symptom was present in 40.7% of the participants. CAO was more common among people aged 60-69 years (OR 2.07, 95% CI 1.13-3.82) and less common among highly educated participants (OR 0.50, 95% CI 0.27-0.93). Being underweight was associated with lower FVC (OR 3.07, 95% CI 2.24-4.20). CONCLUSIONS: A substantial burden of CRD exists among adults in rural Sudan. Investment in CRD prevention and management strategies is needed

A multi-biometric iris recognition system based on a deep learning approach

YesMultimodal biometric systems have been widely applied in many real-world applications due to its ability to deal with a number of significant limitations of unimodal biometric systems, including sensitivity to noise, population coverage, intra-class variability, non-universality, and vulnerability to spoofing. In this paper, an efficient and real-time multimodal biometric system is proposed based on building deep learning representations for images of both the right and left irises of a person, and fusing the results obtained using a ranking-level fusion method. The trained deep learning system proposed is called IrisConvNet whose architecture is based on a combination of Convolutional Neural Network (CNN) and Softmax classifier to extract discriminative features from the input image without any domain knowledge where the input image represents the localized iris region and then classify it into one of N classes. In this work, a discriminative CNN training scheme based on a combination of back-propagation algorithm and mini-batch AdaGrad optimization method is proposed for weights updating and learning rate adaptation, respectively. In addition, other training strategies (e.g., dropout method, data augmentation) are also proposed in order to evaluate different CNN architectures. The performance of the proposed system is tested on three public datasets collected under different conditions: SDUMLA-HMT, CASIA-Iris- V3 Interval and IITD iris databases. The results obtained from the proposed system outperform other state-of-the-art of approaches (e.g., Wavelet transform, Scattering transform, Local Binary Pattern and PCA) by achieving a Rank-1 identification rate of 100% on all the employed databases and a recognition time less than one second per person

pKa Modulation of the Acid/Base Catalyst within GH32 and GH68: A Role in Substrate/Inhibitor Specificity?

Glycoside hydrolases of families 32 (GH32) and 68 (GH68) belong to clan GH-J, containing hydrolytic enzymes (sucrose/fructans as donor substrates) and fructosyltransferases (sucrose/fructans as donor and acceptor substrates). In GH32 members, some of the sugar substrates can also function as inhibitors, this regulatory aspect further adding to the complexity in enzyme functionalities within this family. Although 3D structural information becomes increasingly available within this clan and huge progress has been made on structure-function relationships, it is not clear why some sugars bind as inhibitors without being catalyzed. Conserved aspartate and glutamate residues are well known to act as nucleophile and acid/bases within this clan. Based on the available 3D structures of enzymes and enzyme-ligand complexes as well as docking simulations, we calculated the pKa of the acid-base before and after substrate binding. The obtained results strongly suggest that most GH-J members show an acid-base catalyst that is not sufficiently protonated before ligand entrance, while the acid-base can be fully protonated when a substrate, but not an inhibitor, enters the catalytic pocket. This provides a new mechanistic insight aiming at understanding the complex substrate and inhibitor specificities observed within the GH-J clan. Moreover, besides the effect of substrate entrance on its own, we strongly suggest that a highly conserved arginine residue (in the RDP motif) rather than the previously proposed Tyr motif (not conserved) provides the proton to increase the pKa of the acid-base catalyst

Uma proposta de classificação de analogias para o ensino nas ciências da saúde

O objetivo desse trabalho é contribuir para o processo de ensino de Ciências da Saúde por meio da apresentação de uma nova proposta de classificação de analogias contendo suas categorias, caracterizações e tipologias, elaborada a partir de duas dissertações de mestrado. Sua formulação ocorreu após análise de livros didáticos de Enfermagem e de Fisioterapia. A nova proposta contém oito categorias com respectivas caracterizações e apresenta uma tipologia própria, flexível de modo a ser reconstruída e se aplica a outras áreas do conhecimento. Os resultados apontam a necessidade de ampliar o sistema de classificação utilizado no ensino de ciências de modo a contemplar as analogias encontradas no presente estudo

Crystal structure of recombinant human interleukin-22

Interleukin-22 (IL-10-related T cell-derived inducible factor/IL-TIF/IL-22) is a novel cytokine belonging to the IL-10 family. Recombinant human IL-22 (hIL-22) was found to activate the signal transducers and activators of transcription factors I and 3 as well as acute phase reactants in several hepatoma cell lines, suggesting its involvement in the inflammatory response. The crystallographic structure of recombinant hIL-22 has been solved at 2.0 Angstrom resolution using the SIRAS method. Contrary to IL-10, the hIL-22 dimer does not present an interpenetration of the secondary-structure elements belonging to the two distinct polypeptide chains but results from interface interactions between monomers. Structural differences between these two cytokines, revealed by the crystallographic studies, clearly indicate that, while a homodimer of IL-10 is required for signaling, hIL-22 most probably interacts with its receptor as a monomer.1081051106