925 resultados para Model basic science research
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Monitoring non-ionizing radiant energy is increasingly demanded for many applications such as automobile, biomedical and security system. Thermal type infrared (IR) sensors can operate at room temperature and pyroelectric materials have high sensitivity and accuracy for that application. Working as thermal transducer pyroelectric sensor converts the non-quantified thermal flux into the output measurable quantity of electrical charge, voltage or current. In the present study the composite made of poly(vinylidene fluoride) -PVDF and lead zirconate titanate (PZT) partially recovered with polyaniline (PAni) conductor polymer has been used as sensor element. The pyroelectric coefficient p(T) was obtained by measuring the pyroelectric reversible current, i.e., measuring the thermally stimulated depolarization current (TSDC) after removing all irreversible contribution to the current such as injected charge during polarization of the sample. To analyze the sensing property of the pyroelectric material, the sensor is irradiated by a high power light source (halogen lamp of 250 W) that is chopped providing a modulated radiation. A device assembled in the laboratory is used to change the light intensity sensor, an aluminum strip having openings with diameters ranging from 1 to 10 mm incremented by one millimeter. The sensor element is assembled between two electrodes while its frontal surface is painted black ink to maximize the light absorption. The signal from the sensor is measured by a Lock-In amplifier model SR530 -Stanford Research Systems. The behavior of the output voltage for an input power at several frequencies for PZT-PAni/PVDF (30/ 70 vol%) composite follows the inverse power law (1/ f) and the linearity can be observed in the frequency range used.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Purpose: Temporomandibular disorders (TMD) are recognized as one of the mostcontroversial topics in dentistry, despite the fact that both basic science and clinicalresearchers have currently reached some degree of consensus. This study aimed toconduct a questionnaire-based survey about the management of TMD patients bygeneral dental practitioners (GDPs).Materials and Methods: One hundred fifty-one GDPs with a private practice in a cityof southern Brazil were included, independent of school of origin, gender, graduationyear, and curriculum content. All participants were administered a questionnaire aboutthe management of patients with TMD, and the responses were analyzed by binomialand chi-square tests (α = 0.05).Results: Of the GDPs, 88.7% received TMD patients, who were primarily diagnosedon the basis of medical history (36.6%) or physical examination (30.4%). Of these,65.4% referred the patients elsewhere, primarily to specialists in occlusion (36.1%) ororthodontics (29.7%). Occlusal splinting was the most commonly used managementmodality (20.8%), followed by occlusal adjustment (18.1%) and pharmacotherapy(16.6%). Splints were fabricated in maximum habitual intercuspation or centric re-lation depending on individual patient (54.8%). The hard stabilization form was themost common type of appliance used (35.0%). Moreover, 73.8% of the GDPs didnot employ semi-adjustable articulators, and 69.5% adjusted the appliances at thetime of fixing. The duration of splint use and the frequency of follow-up were con-sidered patient dependent by 62.1% and 72.8%, respectively. GDPs considered thetwo major TMD etiologic categories as multifactorial (20.8%) and occlusion (19.9%).Multidisciplinary medical and dental treatment was considered necessary by 97.9%.Conclusions: The evaluated general dental practitioners manage TMD patients ac-cording to international guidelines.
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Literature is a treasure for humanity and for the school. It causes psychological function of the individual, inserts it in the context of various cultures and historic moments, and, by having formative nature, School and Literature are intrinsecally related institutions. But literature is not the end of the first teaching, while the school has the purpose of teaching literature. Literature is not a source of good leads standards; have to be educated without this process to misrepresent. Thus, it was estalished is to investigate the inadequacy of schooling of Children's Literature pointed out by Soares in 2006, is still reality that becomes present in school or if there was any change in that status. Specific objectives were established: 1)Scanning separately in each of the books education system, from first to fifth grade of elementary school, according to the following categories involving education of literary reading: selection of genres and authors; presentation of these genres and no change from one genre to another; 2)analyze the way children's literature is presented by note-books analyzed education system develop the sensitivity of the student for pluris-signification and expressiveness of literary language, while fulfilling its social function and knowledge; 3)review the comprehension activities of literary reading proposed by notebooks to seize their educational goals. Therefore, we carried out basic theoretical research, demonstrating the functions of literature and the teaching of literature in school, and documentary research. Were analyzed 20 documents (the system apostilled notebooks), paying attention to classwork it to him of genres, authors and works chosen to be worked out, observing the cases of texts fragmentation and transport the genre to the page of the notebook system apostilled, and investigating the goals of literary reading instruction through the analysis of comprehension activities. The data received quantitative...
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The present paper is a reflection on the diagnosis of Attention Deficit Hyperactivity Disorder (ADHD) and its relations to the process of medicalization as well as the meanings and perspectives apprehended through three case studies of children diagnosed with such disorder in a doctoral research in which the main purpose was to understand the meanings and peculiarities of ADHD symptomatology .We’ve utilized the model of qualitative research, grounded in psychoanalytic perspective, and conducted the psychodiagnosis for three children who were referred for psychological treatment. The survey found that those children had few experiences of both continence and frustration tolerance. It was evidenced how the school uses the logic of medicalization to try solving the problems with their children when it came to the school dimension. The variety of symptomatic manifestations and psychic dynamics presented by the cases that were studied revealed the weaknesses and inconsistencies of the referred diagnosis.
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The mineral sector is of utmost importance for Brazilian economic growth, an area which depends on basic geological research to enlarge known deposits and in process of mining, besides discovering new occurrences and mineral deposits. This set of activities is named mineral research, which planning involves economy concepts, market demands and use of methods and techniques for geological evaluation, direct and indirect. This paper aim at performing geophysical detailing on occurrences of supergenic manganese located in the northwest portion of the State of São Paulo, Itapira, for spatial dimensioning of mineral targets, besides the attempt to correlate among the content on physical parameter measured by geophysics. The lack of scientific publications by Brazilian researchers in this theme, availability of previous studies for the selected targets, commercial importance of the mineral goods for the Brazilian Trade Balance, justify the performance of the present research project
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As an undergraduate sociology major, the only thing I learned about Oklahoman Laud Humphreys's classic, Tearoom Trade (1970) was how it violated standards of informed consent in social science research. As Galliher, Brekhus, and Keys recount in their biography, Laud Humphreys: Prophet of Homosexuality and Sociology, sociology graduate student Laud Humphreys needed to supplement his (quite likely, participant) observational research of men who had sex in public bathrooms (i.e., tearooms) in St. Louis in the mid-1960s with a formal questionnaire. Knowing that these men would never agree if they knew they were selected because of their participation in highly stigmatized and criminal behavior, Humphreys recorded their license plates, got their home addresses, and interviewed them as part of a "community health survey." Herein lies the deception and the major source of the controversy. What I didn't fully appreciate when I was a student, however, and what the authors so deftly illuminate is the importance of this work not only for debates around ethical issues of social science research, but more importantly, perhaps, for the study of sexuality, deviance, and urban life.
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We verified the relevance of measuring fecal glucocorticoid metabolites (FGM) to assess the stress response of the Syrian hamster. Male and female hamsters (n = 10 each) were submitted to an adrenocorticotropic hormone (ACTH) challenge test, whereas animals in the control group received 0.5 mL of sterile isotonic saline solution. All feces voided by each animal were collected at 4 h intervals from 24 h before (baseline) until 48 h after injections. FGM were quantified using an 11-oxoetiocholanolone enzyme immunoassay (EIA). Basal concentrations of FGM were almost four times higher in males than in females. Following ACTH administration, FGM levels started rising from 8 h onwards, reaching peak concentrations 20 or 28 h post injection in males and females, respectively. Despite the much higher absolute concentrations present in males, the relative increase (500%) in response to the ACTH stimulation was similar in both sexes. Sex differences in FGM levels are in accordance with results reported by others regarding the hamster adrenal physiology. The comparison of the adrenocortical response of males and females to an ACTH challenge provided new information about the amplitude and the timing of such a response and the excretion of glucocorticoids in both sexes. We demonstrated for the first time in the Syrian hamster that adrenocortical activity can be monitored in fecal samples in a noninvasive way. Our study provides a humane, practical, and noninvasive alternative to blood removal and therefore a powerful tool for stress-related studies in a species frequently used as an animal model in medical research.
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The ALICE Collaboration has measured inclusive J/psi production in pp collisions at a center-of-mass energy root s = 2.76 TeV at the LHC. The results presented in this Letter refer to the rapidity ranges vertical bar y vertical bar < 0.9 and 2.5 < y <4 and have been obtained by measuring the electron and muon pair decay channels, respectively. The integrated luminosities for the two channels are L-int(e) = 1.1 nb(-1) and L-int(mu) = 19.9 nb(-1), and the corresponding signal statistics are N-J/psi(e+e-) = 59 +/- 14 and N-J/psi(mu+mu-) = 1364 +/- 53. We present d sigma(J/psi)/dy for the two rapidity regions under study and, for the forward-y range, d(2)sigma(J/psi)/dydp(t) in the transverse momentum domain 0 < p(t) < 8 GeV/c. The results are compared with previously published results at root s = 7 TeV and with theoretical calculations. (C) 2012 CERN. Published by Elsevier B.V. All rights reserved.
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Background: The diaphragm is the major respiratory muscle affected by Duchenne muscular dystrophy (DMD) and is responsible for causing 80% of deaths. The use of mechanical forces that act on the body or intermittent pressure on the airways improves the quality of life of patients but does not prevent the progression of respiratory failure. Thus, diseases that require tissue repair, such as DMD, represent a group of pathologies that have great potential for cell therapy. The application of stem cells directly into the diaphragm instead of systemic application can reduce cell migration to other affected areas and increase the chances of muscle reorganisation. The mdx mouse is a suitable animal model for this research because its diaphragmatic phenotype is similar to human DMD. Therefore, the aim of this study was to assess the potential cell implantation in the diaphragm muscle after the xenotransplantation of stem cells. Methods: A total of 9 mice, including 3 control BALB/Cmice, 3 5-month-old mdx mice without stem cell injections and 3 mdx mice injected with stem cells, were used. The animals injected with stem cells underwent laparoscopy so that stem cells from GFP-labelled rabbit olfactory epithelium could be locally injected into the diaphragm muscle. After 8 days, all animals were euthanised, and the diaphragm muscle was dissected and subjected to histological and immunohistochemical analyses. Results: Both the fresh diaphragm tissue and immunohistochemical analyses showed immunopositive GFP labelling of some of the cells and immunonegativity of myoblast bundles. In the histological analysis, we observed a reduction in the inflammatory infiltrate as well as the presence of a few peripheral nuclei and myoblast bundles. Conclusion: We were able to implant stem cells into the diaphragm via local injection, which promoted moderate muscle reorganisation. The presence of myoblast bundles cannot be attributed to stem cell incorporation because there was no immunopositive labelling in this structure. It is believed that the formation of the bundles may have been stimulated by cellular signalling mechanisms that have not yet been elucidated.
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The ALICE Collaboration has studied J/psi production in pp collisions at root s = 7 TeV at the LHC through its muon pair decay. The polar and azimuthal angle distributions of the decay muons were measured, and results on the J/psi polarization parameters lambda(theta) and lambda(phi) were obtained. The study was performed in the kinematic region 2: 5 < y < 4, 2 < p(t) < 8 GeV/c, in the helicity and Collins-Soper reference frames. In both frames, the polarization parameters are compatible with zero, within uncertainties.
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Redescription of the enigmatic Thoracotropis cypriformis Freeman (Diptera, Mycetophilidae). The Chilean species Thoracotropis cypriformis, type species of the monotypic genus Thoracotropis, is redescribed based on the only known specimen, the holotype. Habitus, head, wing venation, and male terminalia are illustrated. Comments are made on the diagnostic features of the genus and on its position in the subfamily to which it is usually assigned, the Leiinae.
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This meta-analysis of land-cover transformations of the past 10-15 years in tropical forest-agriculture frontiers world-wide shows that swidden agriculture decreases in landscapes with access to local, national and international markets that encourage cattle production and cash cropping, including biofuels. Conservation policies and practices also accelerate changes in swidden by restricting forest clearing and encouraging commercial agriculture. However, swidden remains important in many frontier areas where farmers have unequal or insecure access to investment and market opportunities, or where multi-functionality of land uses has been preserved as a strategy to adapt to current ecological, economic and political circumstances. In some areas swidden remains important simply because intensification is not a viable choice, for example when population densities and/or food market demands are low. The transformation of swidden landscapes into more intensive land uses has generally increased household incomes, but has also led to negative effects on the social and human capital of local communities to varying degrees. From an environmental perspective, the transition from swidden to other land uses often contributes to permanent deforestation, loss of biodiversity, increased weed pressure, declines in soil fertility, and accelerated soil erosion. Our prognosis is that, despite the global trend towards land use intensification, in many areas swidden will remain part of rural landscapes as the safety component of diversified systems, particularly in response to risks and uncertainties associated with more intensive land use systems. (C) 2011 Elsevier Ltd. All rights reserved.
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The differential production cross section of electrons from semileptonic heavy-flavor hadron decays has been measured at midrapidity (\y\ < 0.5) in proton-proton collisions at root s = 7 TeV with ALICE at the LHC. Electrons were measured in the transverse momentum range 0.5 < p(t) < 8 GeV/c. Predictions from a fixed-order perturbative QCD calculation with next-to-leading-log resummation agree with the data within the theoretical and experimental uncertainties. DOI: 10.1103/PhysRevD.86.112007
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The Neotropical tribe Trimezieae are taxonomically difficult. They are generally characterized by the absence of the features used to delimit their sister group Tigridieae. Delimiting the four genera that make up Trimezieae is also problematic. Previous family-level phylogenetic analyses have not examined the monophyly of the tribe or relationships within it. Reconstructing the phylogeny of Trimezieae will allow us to evaluate the status of the tribe and genera and to examine the suitability of characters traditionally used in their taxonomy. Maximum parsimony and Bayesian phylogenetic analyses are presented for 37 species representing all four genera of Trimezieae. Analyses were based on nrITS sequences and a combined plastid dataset. Ancestral character state reconstructions were used to investigate the evolution of ten morphological characters previously considered taxonomically useful. Analyses of nrITS and plastid datasets strongly support the monophyly of Trimezieae and recover four principal clades with varying levels of support; these clades do not correspond to the currently recognized genera. Relationships within the four clades are not consistently resolved, although the conflicting resolutions are not strongly supported in individual analyses. Ancestral character state reconstructions suggest considerable homoplasy, especially in the floral characters used to delimit Pseudotrimezia. The results strongly support recognition of Trimezieae as a tribe but suggest that both generic- and species-level taxonomy need revision. Further molecular analyses, with increased sampling of taxa and markers, are needed to support any revision. Such analyses will help determine the causes of discordance between the plastid and nuclear data and provide a framework for identifying potential morphological synapomorphies for infra-tribal groups. The results also suggest Trimezieae provide a promising model for evolutionary research.