926 resultados para Learning how to be a teacher
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Control recommendations are presented for four genetic or familial diseases that cause significant morbidity and mortality in affected English Bull Terriers. Bull Terrier polycystic kidney disease is an autosomal dominant disease diagnosed by detecting a minimum of three renal cysts, with cysts present in both kidneys, and similarly affected family members to confirm the inherited nature of the cysts. Bull Terrier hereditary nephritis is an autosomal dominant disease diagnosed in otherwise normal animals with urinary protein: creatinine ratios persistently >0.3 and no significant urinary sediment, a family history of the disease, and characteristic glomerular basement membrane lesions. Mitral valve myxomatous degeneration and left ventricular outflow tract obstruction in Bull Terriers are familial diseases diagnosed by auscultating characteristic murmurs in affected animals. Excluding animals with these clinical signs from the breeding pool will reduce the prevalence rates of these diseases, however maintenance of an effective population size is also important. Providing breeders with information on genetics, including the risks associated with inbreeding and the benefits of outcrossing, is likely to improve canine breeding practices, thus increasing fitness and fecundity of these purebred dogs.
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This paper is a contribution for the assessment and comparison of magnet properties based on magnetic field characteristics particularly concerning the magnetic induction uniformity in the air gaps. For this aim, a solver was developed and implemented to determine the magnetic field of a magnetic core to be used in Fast Field Cycling (FFC) Nuclear Magnetic Resonance (NMR) relaxometry. The electromagnetic field computation is based on a 2D finite-element method (FEM) using both the scalar and the vector potential formulation. Results for the magnetic field lines and the magnetic induction vector in the air gap are presented. The target magnetic induction is 0.2 T, which is a typical requirement of the FFC NMR technique, which can be achieved with a magnetic core based on permanent magnets or coils. In addition, this application requires high magnetic induction uniformity. To achieve this goal, a solution including superconducting pieces is analyzed. Results are compared with a different FEM program.
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Dissertação apresentada à Escola Superior de Educação de Lisboa para obtenção de grau de Mestre em Ciências da Educação - Especialização em Educação Especial
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Chrysonilia sitophila is a common mould in cork industry and has been identified as a cause of IgE sensitization and occupational asthma. This fungal species have a fast growth rate that may inhibit others species’ growth causing underestimated data from characterization of occupational fungal exposure. Aiming to ascertain occupational exposure to fungi in cork industry, were analyzed papers from 2000 about the best air sampling method, to obtain quantification and identification of all airborne culturable fungi, besides the ones that have fast-growing rates. Impaction method don’t allows the collection of a representative air volume, because even with some media that restricts the growth of the colonies, in environments with higher fungal load, such as cork industry, the counting of the colonies is very difficult. Otherwise, impinger method permits the collection of a representative air volume, since we can make dilution of the collected volume. Besides culture methods that allows fungal identification trough macro- and micro-morphology, growth features, thermotolerance and ecological data, we can apply molecular biology with the impinger method, to detect the presence of non-viable particles and potential mycotoxin producers’ strains, and also to detect mycotoxins presence with ELISA or HPLC. Selection of the best air sampling method in each setting is crucial to achieve characterization of occupational exposure to fungi. Information about the prevalent fungal species in each setting and also the eventual fungal load it’s needed for a criterious selection.
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This paper is a contribution for the assessment and comparison of magnet properties based on magnetic field characteristics particularly concerning the magnetic induction uniformity in the air gaps. For this aim, a solver was developed and implemented to determine the magnetic field of a magnetic core to be used in Fast Field Cycling (FFC) Nuclear Magnetic Resonance (NMR) relaxometry. The electromagnetic field computation is based on a 2D finite-element method (FEM) using both the scalar and the vector potential formulation. Results for the magnetic field lines and the magnetic induction vector in the air gap are presented. The target magnetic induction is 0.2 T, which is a typical requirement of the FFC NMR technique, which can be achieved with a magnetic core based on permanent magnets or coils. In addition, this application requires high magnetic induction uniformity. To achieve this goal, a solution including superconducting pieces is analyzed. Results are compared with a different FEM program.
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High loads of fungi have been reported in different types of waste management plants. This study intends to assess fungal contamination in one waste-sorting plant before and after cleaning procedures in order to analyze their effectiveness. Air samples of 50 L were collected through an impaction method, while surface samples, taken at the same time, were collected by the swabbing method and subject to further macro- and microscopic observations. In addition, we collected air samples of 250 L using the impinger Coriolis μ air sampler (Bertin Technologies) at 300 L/min airflow rate in order to perform real-time quantitative PCR (qPCR) amplification of genes from specific fungal species, namely Aspergillus fumigatus and Aspergillus flavus complexes, as well as Stachybotrys chartarum species. Fungal quantification in the air ranged from 180 to 5,280 CFU m−3 before cleaning and from 220 to 2,460 CFU m−3 after cleaning procedures. Surfaces presented results that ranged from 29 × 104 to 109 × 104 CFU m−2 before cleaning and from 11 × 104 to 89 × 104 CFU m−2 after cleaning. Statistically significant differences regarding fungal load were not detected between before and after cleaning procedures. Toxigenic strains from A. flavus complex and S. chartarum were not detected by qPCR. Conversely, the A. fumigatus species was successfully detected by qPCR and interestingly it was amplified in two samples where no detection by conventional methods was observed. Overall, these results reveal the inefficacy of the cleaning procedures and that it is important to determine fungal burden in order to carry out risk assessment.
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Chitosan biocompatibility and biodegradability properties make this biopolymer promising for the development of advanced internal fixation devices for orthopedic applications. This work presents a detailed study on the production and characterization of three dimensional (3D) dense, non-porous, chitosan-based structures, with the ability to be processed in different shapes, and also with high strength and stiffness. Such features are crucial for the application of such 3D structures as bioabsorbable implantable devices. The influence of chitosan's molecular weight and the addition of one plasticizer (glycerol) on 3D dense chitosan-based products' biomechanical properties were explored. Several specimens were produced and in vitro studies were performed in order to assess the cytotoxicity of these specimens and their physical behavior throughout the enzymatic degradation experiments. The results point out that glycerol does not impact on cytotoxicity and has a high impact in improving mechanical properties, both elasticity and compressive strength. In addition, human mesenchymal stem/stromal cells (MSC) were used as an ex-vivo model to study cell adhesion and proliferation on these structures, showing promising results with fold increase values in total cell number similar to the ones obtained in standard cell culture flasks. (C) 2014 Elsevier Ltd. All rights reserved.
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We show that the number of merger proposals (frequency-based deterrence) is a more appropriate indicator of underlying changes in merger policy than the relative anti-competitiveness of merger proposals (composition-based deterrence). This has strong implications for the empirical analysis of the deterrence effects of merger policy enforcement, and potential implications regarding how to reduce anti-competitive merger proposals.
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Learning systems are evolving from component based and centralized architectures towards service oriented and decentralized architectures. The standardization of e-learning content and interoperability is a powerful force in this evolution. In this chapter we put in perspective the evolution of e-learning systems and standards, and argue that specialized services will play an important role in future learning systems, especially in those targeted for competitive learning.
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The aim of this work was to assess the influence in the diagnostic value for human hydatid disease of the composition of bovine hydatid cyst fluid (BHCF) obtained from fertile (FC) and non-fertile cysts (NFC). Eight batches from FC and 5 from NFC were prepared and analysed with respect to chemical composition: total protein, host-derived protein, carbohydrate and lipid contents. No differences were observed in the first two parameters but carbohydrate and lipid contents were shown to be higher in batches from FC than in those from NFC. Bands of 38 and 116 kD in SDS-PAGE profiles were observed to be present in BHCF from FC only. Two pools were prepared from BHCF batches obtained from FC (PFC) and NFC (PNFC), respectively. Antigen recognition patterns were analysed by immunoblot. Physicochemical conditions for adsorption of antigens to the polystyrene surface (ELISA plates) were optimized. The diagnostic value of both types of BHCF as well as the diagnostic relevance of oxidation of their carbohydrate moieties with periodate were assessed by ELISA using 42 serum samples from hydatid patients, 41 from patients with other disorders, and 15 from healthy donors. Reactivity of all sera against native antigen were tested with and without free phosphorylcholine. The best diagnostic efficiency was observed using BHCF from periodate-treated PFC using glycine buffer with strong ionic strength to coat ELISA plates.
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Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Filosofia-Estética
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Precocious puberty, defined as the development of secondary sexual characteristics before the age of 8, often leads to anxiety in patients and their families but also in clinicians searching for the final diagnosis. After adequate investigation, the majority of the cases in girls turn out to be idiopathic. The authors present a case of McCune Albright syndrome in order to call attention to a rare cause of sexual precocity and the value of ultrasound in the evaluation of these situations. 10 years old infant girl admitted in our department due to irregular menstrual bleeding. She experienced a vaginal bleeding by the age of 3 which led to the diagnosis of McCune Albright Syndrome after a complete evaluation. Pubertal assessment revealed a reversed sequence in the remaining events with adrenarche at 5 and thelarche at 8. Hormonal evaluation demonstrated low FSH and LH levels (11,2 and 6,72 respectively) with high estrogen (204). Pelvic ultrasound showed a normal sized uterus (73x 29x32 mm), endometrial thickness of 5 mm and ovaries with several microfollicles and a copus luteum measuring 23 mm in the right ovary. McCune Albright syndrome is a very uncommon cause of sexual precocity that should, however, be suspected in all infant girls who present with vaginal bleeding. It is characterized by a triad: polyostotic fibrous dysplasia, gonadotropin-independent precocious puberty and café-au-lait skin spots. Due to autonomous production of estrogen by the ovaries, ultrasound image of the female reproductive tract is inconsistent with chronologic age. Pelvic ultrasound demonstrates a normal sized uterus with a well defined cervix and clearly identified ovaries with several follicles, similar to adult women of reproductive age. Ultrasonography of the pelvis has also an important role excluding other causes of GnRH-independent precocious puberty conditions like ovarian cysts or tumors.