299 resultados para Start study
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)
Resumo:
The single phase induction motors needs two stator windings to produce rotating magnetic field : one main winding and the other auxiliary winding. The aim of the auxiliary winding is to create the rotating electromagnetic field when the machine is started-up and is afterwards turned off, generally through the centrifugal switch coupled together with the shaft of the machine rotor. The main purpose of this document is to evaluate the influence that the two windings have on the external characteristics of the single phase induction motor. For this purpose, two different kinds of windings were carried out and simulated, with the proposal to obtain some benefits. The main winding and the auxiliary winding were prepared and mounted on a prototype. The simulation was done via software based FEM, to make the extraction and results analysis possible. This results are shown at the end this document.
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Introdução e objetivo: A exposição à luz natural tem efeitos relevantes no sistema de temporização biológica. Pode-se supor que essa exposição poderia promover um ajuste melhor entre os ritmos biológicos e os horários de início de trabalho entre trabalhadores diurnos de ambientes externos. O objetivo deste estudo foi comparar a matutinidade/vespertinidade e a relação entre o horário de trabalho real e o ideal em trabalhadores diurnos expostos a condições de iluminação distintas. Métodos: O estudo foi conduzido com dois grupos de trabalhadores (n=49) que residiam em uma área rural e tinham condições sociais similares. Um grupo trabalhava em ambiente interno (n=20, idade média 30,8 anos (21-50); desvio padrão=9,8) e o outro grupo trabalhava em ambiente externo (n=29, idade média 30,8 anos (17- 50); desvio padrão=10,0). Os trabalhadores preencheram um questionário de matutinidade/vespertinidade (MEQ). Foi realizada uma ANOVA de um fator com o intuito de comparar os escores do MEQ entre os dois grupos de trabalhadores. Resultados: Como esperado, o Grupo do Ambiente Externo (GAE) apresentou média de escores mais elevada que o Grupo do Ambiente Interno (GAI), o que significa uma tendência à matutinidade (GAE: 58,4±7,9; GAI; 47,4±6,4), com significância estatística (F=26,22; p<0,001). De acordo com os dados relatados em relação aos horários de trabalho, o GAE gostaria de atrasar seu horário de trabalho em 31 minutos, em média, enquanto que o GAI gostaria de atrasar em 96 minutos seu horário de trabalho (F=7,71; p<0,01). Conclusões: Os resultados desse estudo sugerem que a exposição à luz natural pode promover um ajuste melhor aos horários de início de trabalho matutinos
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P>Esophagocoloplasty and gastric transposition are two major methods for esophageal substitution in children with esophageal atresia, and there is broad agreement that these operations should not be performed before the children start walking. However, there are some reported advantages of performing such operations in the first months of life or in the neonatal period. In this study, we compared our experience with esophageal substitution procedures performed in walking children with esophageal atresia, with the outcomes of children who had the operation before the third month of life reported in the literature. The purpose of this study was to establish if we have to wait until the children start walking before indicating the esophageal replacement procedure. From February 1978 to October 2009, 129 children with esophageal atresia underwent esophageal replacement in our hospital (99 colonic interpositions and 30 gastric transpositions). The records of these patients were reviewed for data regarding demographics, complications (leaks, graft failures, strictures, and graft torsion), and mortality and compared with those reported in the two main articles on esophageal replacement in the neonatal period or in patients less than 3 months of age. The main complication of our casuistic was cervical anastomosis leakage, which sealed spontaneously in all except in four patients. One patient of the esophagocoloplasty group developed graft necrosis and three patients in the gastric transposition group had gastric outlet obstruction, secondary to axial torsion of the stomach placed in the retrosternal space. The long-term outcome of the patients in both groups was considered good to excellent in terms of normal weight gain, absence of dysphagia, and other gastrointestinal symptoms. The comparisons of the main complications and mortality rates in walking children with esophageal substitutions performed in the first months of life showed that the incidences of cervical anastomotic leaks and graft failures were similar, but mortality rate in the first few months of life was significantly greater than that observed in our group of patients (P = 0.001). Based on the comparison of our results with those of published series, we conclude that the recommendation of performing esophagocoloplasty or total gastric transposition in children with esophageal atresia after they start walking is still valid.
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Background: Inhaled corticosteroids (ICSs) are recommended as the first line of treatment in children with moderate-to-severe asthma. Exhaled nitric oxide (ENO) has been proposed as a clinically useful marker of control that might help identify patients in whom ICS dose may be safely reduced. Objective: To evaluate the ability of ENO to predict future asthma exacerbations in children with moderate-to-severe asthma undergoing ICS tapering. Methods: This is an observational study with no control group. ENO was measured biweekly for 14 weeks in 32 children with moderate-to-severe asthma who were undergoing ICS tapering. Clinical evaluations and spirometry were performed concomitantly, and families kept daily diaries to record symptoms between visits. We used generalized estimating equations to model the In (odds) of an asthma exacerbation in the subsequent 2-week interval as a function of ENO level at the start of the interval while adjusting for age, sex, asthma severity, and current medication use. Results: We were able to successfully lower ICS doses in 10 (56%) of the 18 children with moderate asthma and in 3 (21%) of the 14 children with severe asthma. In 83 of the 187 follow-up clinical evaluations, children were determined to have had an exacerbation during the preceding 2 weeks. ENO levels, whether expressed as a continuous variable or dichotomized, were not associated with future risk for exacerbations in either unadjusted or adjusted models. Conclusion: ENO was not a useful clinical predictor of future asthma exacerbations for children with moderate-to-severe asthma undergoing ICS tapering. Ann Allergy Asthma Immunol. 2009; 103:206-211.
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Objective. To determine pregnancy outcome and fetal loss risk factors in patients with juvenile systemic lupus erythematosus (JSLE). Methods. A total of 315 female patients with JSLE followed in 12 Brazilian pediatric rheumatology centers were consecutively selected. Menarche was observed in 298 (94.6%) patients. Patients` medical records were reviewed for pregnancy outcomes and demographic, clinical, and therapeutic data. Results. A total of 24 unplanned pregnancies occurred in 298 (8%) patients. The outcomes were 5 (21%) early fetal losses (prior to 16 wks gestation), 18 (75%) live births, and 1 (4%) death due to preeclampsia and premature birth. The frequencies of active diffuse proliferative glomerulonephritis, proteinuria >= 0.5 g/day, and arterial hypertension at the beginning of pregnancy were higher in pregnancies resulting in fetal losses than in live births [60% vs 5% (p = 0.02), 60% vs 5% (p = 0.02), 60% vs 5% (p = 0.02), respectively]. JSLE pregnancies with fetal losses had a significantly higher mean SLE Disease Activity Index 2000 (SLEDAI-2K) at the start of pregnancy compared with those with live births (9.40 +/- 7.47 vs 3.94 +/- 6.00; p = 0.049). Four pregnancies were inadvertently exposed to intravenous cyclophosphamide therapy for renal involvement despite contraceptive prescriptions, resulting in fetal loss in 3 (p = 0.02). In multivariate analysis only intravenous cyclophosphamide use at start of pregnancy (OR 25.50, 95% CI 1.72-377.93, p = 0.019) remained as an independent risk factor for fetal loss. Conclusion. We identified immunosuppressive therapy as the major contributing factor for fetal loss in JSLE, reinforcing the importance of contraception.
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Previous studies have shown differences in clinical features of obsessive-compulsive disorder (OCD) between men and women, including mean age at onset of obsessive-compulsive symptoms (OCS), types of OCS, comorbid disorders, course, and prognosis. The aim of this study was to compare male and female Brazilian patients with OCD on several demographic and clinical characteristics. Three hundred thirty Outpatients with OCD (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition [DSM-IV], criteria) who sought treatment at 3 Brazilian public universities and at 2 private practice clinics in the city of Sao Paulo were evaluated. The assessment instruments used were the Yale-Brown Obsessive-Compulsive Scale to evaluate OCD severity and symptoms, the Beck Depression and Anxiety Inventories, the Yale Global Tic Severity Scale, and the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Axis I Disorders to assess psychiatric comorbidity. Fifty-five percent of the patients (n = 182) were men who were significantly more likely than women to be single and to present sexual, religious, and symmetry obsessions and mental rituals. They also presented earlier onset of OCS and earlier symptom interference in functioning, and significantly more comorbid tic disorders and posttraumatic stress disorder. Women, besides showing significantly higher mean scores in the Beck Depression and Anxiety Inventories, were more likely to present comorbid simple phobias, eating disorders in general and anorexia in particular, impulse control disorders in general, and compulsive buying and skin picking in particular. No significant differences were observed between sexes concerning family history of OCS or OCD, and global symptoms severity, either in obsession or compulsive subscale. The present study confirms the presence of sex-related differences described in other countries and cultures. The fact that the OCS start earlier and probably have a worse impact in men can eventually lead to more specific and efficacious treatment approaches for these patients. (C) 2009 Elsevier Inc. All rights reserved.
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Background Several mechanisms have been suggested to explain the association between adversities across life and dementia. This study aimed to investigate the association between indicators of socioeconomic disadvantages throughout the life-course and dementia among older adults in Sao Paulo, Brazil and to explore possible causal pathways. Methods We used baseline data from the SPAH study which involved participants aged 65 years and older (n = 2005). The outcome of interest was prevalent dementia. Exposures included in the analyses were socioeconomic position (SEP) indicators in childhood (place of birth and literacy) and adulthood (occupation and income), anthropometric measurements as markers of intrauterine and childhood environment (head circumference and leg length), smoking, diabetes and hypertension. Logistic regression models were used to test the hypothesized pathways and to assess whether there was an association between cumulative adversities across the life course and prevalent dementia. Results Indicators of socioeconomic disadvantage in early life were associated with increased prevalence of dementia. This association was partially mediated through adulthood SEP. Head circumference and leg length were also clearly associated with dementia but there was no evidence that this association was mediated by early life socioeconomic disadvantage. There was an association between cumulative unfavourable conditions across the life course and dementia. Conclusions Early life disadvantages seem to operate through biological mechanisms associated with passive brain reserve and opportunities in life representing active cognitive reserve. Prevention of dementia should start early in life and continue through life span as seen with many other chronic diseases.
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The progress of science in search of new techniques of the nerve regeneration and the functional repair in reinnervated muscle has been the target of many researchers around the world. Consequently, nerves and muscles in different body segments asked for more enlightenment of their morphology, their interrelation with other anatomic structures and their peculiarities. One of the most significant areas that need deeper studies is the region of the head and neck, since they are often affected by important pathologies. In order to offer the researcher`s community a morphological myoneural interaction model, this study elected the levator labii superioris muscle and its motor nerve, the buccal branch of the facial nerve (VII pair) not only for its special characteristics, but also its value on the facial expression. The rat was chosen for this investigation for being easy to obtain, to keep, to manipulate and to compare this experiment with many others studies previously published. The techniques used were Mesoscopic (dissection), histoenzymologic and morphometric ones. In the results the muscle proved to have a predominance of fast twich fibers (FG and FOG) and superficial location, with a proximal bone and a distal cutaneous insertion. Its motor nerve, the buccal branch of the facial nerve (VII pair), breaks through the muscle belly into its deep face, and comprised a heterogeneous group of myelinic nerve fibers disposed in a regular form in all fascicle. Near the motor point, the nerve showed to be composed of two fascicles with different sizes. Due to the small nerve dimensions, the nerve fibers have a smaller diameter if compared to the motor nerve of pectineus muscle of the cat. Further studies with neural tracers have already had a start in order to provide more information about the distribution and the architecture of these fibers.
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The air fluorescence detector of the Pierre Auger Observatory is designed to perforin calorimetric measurements of extensive air showers created by Cosmic rays of above 10(18) eV. To correct these measurements for the effects introduced by atmospheric fluctuations, the Observatory contains a group Of monitoring instruments to record atmospheric conditions across the detector site, ail area exceeding 3000 km(2). The atmospheric data are used extensively in the reconstruction of air showers, and are particularly important for the correct determination of shower energies and the depths of shower maxima. This paper contains a summary of the molecular and aerosol conditions measured at the Pierre Auger Observatory since the start of regular operations in 2004, and includes a discussion of the impact of these measurements oil air shower reconstructions. Between 10(18) and 10(20) eV, the systematic Uncertainties due to all atmospheric effects increase from 4% to 8% in measurements of shower energy, and 4 g cm(-2) to 8 g cm(-2) in measurements of the shower maximum. (C) 2010 Elsevier B.V. All rights reserved.
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The purpose of this study was to evaluate the clinical performance of glass ionomer cement (GIC) restorations comparing two minimally invasive methods in permanent teeth after 12 months. Fifty pregnant women (second trimester of pregnancy), mean age 22 ± 5.30 years, were treated by two previously trained operators. The treatment approaches tested were: chemomechanical method (CarisolvTM; MediTeam) and atraumatic restorative treatment (ART). A split-mouth study design was used in which the two treatments were randomly placed in 50 matched pairs of permanent teeth. The chemomechanical method (CM) was the test group and the ART was the control group. The treatments were performed in Public Health Centers. The tested restorative material was a high-strength GIC (Ketac Molar; 3M/ESPE). The restorations were placed according to the ART guidelines. Two calibrated independent examiners evaluated the restorations in accordance with ART criteria. The inter-examiner kappa was 0.97. Data were analyzed using 95% confidence interval on the binomial distribution and Fisher's exact test at 5% significance level. In a 12-month follow-up, 86% of the restorations were evaluated. In the test group (CM), 100% (CI=93.3-100%) of the restorations were considered successful. In the control group (ART) 97.6% (CI=87.4-99.9%) of the restorations were considered successful and 2.4% unsuccessful (marginal defect >0.5 mm). There was no statistically significant difference between the 12-mounth success rate for both groups (Fisher's exact test: P=0.49) and between the two operators (Fisher's exact test: P=1.00). Both minimally invasive methods, chemomechanical method and ART, showed a similar clinical performance after 12 months of follow up.
Resumo:
The aim of this study was to comparatively assess dental arch width, in the canine and molar regions, by means of direct measurements from plaster models, photocopies and digitized images of the models. The sample consisted of 130 pairs of plaster models, photocopies and digitized images of the models of white patients (n = 65), both genders, with Class I and Class II Division 1 malocclusions, treated by standard Edgewise mechanics and extraction of the four first premolars. Maxillary and mandibular intercanine and intermolar widths were measured by a calibrated examiner, prior to and after orthodontic treatment, using the three modes of reproduction of the dental arches. Dispersion of the data relative to pre- and posttreatment intra-arch linear measurements (mm) was represented as box plots. The three measuring methods were compared by one-way ANOVA for repeated measurements (α = 0.05). Initial / final mean values varied as follows: 33.94 to 34.29 mm / 34.49 to 34.66 mm (maxillary intercanine width); 26.23 to 26.26 mm / 26.77 to 26.84 mm (mandibular intercanine width); 49.55 to 49.66 mm / 47.28 to 47.45 mm (maxillary intermolar width) and 43.28 to 43.41 mm / 40.29 to 40.46 mm (mandibular intermolar width). There were no statistically significant differences between mean dental arch widths estimated by the three studied methods, prior to and after orthodontic treatment. It may be concluded that photocopies and digitized images of the plaster models provided reliable reproductions of the dental arches for obtaining transversal intra-arch measurements.
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This in situ study investigated, using scanning electron microscopy, the effect of stimulated saliva on the enamel surface of bovine and human substrates submitted to erosion followed by brushing abrasion immediately or after one hour. During 2 experimental 7-day crossover phases, 9 previously selected volunteers wore intraoral palatal devices, with 12 enamel specimens (6 human and 6 bovine). In the first phase, the volunteers immersed the device for 5 minutes in 150 ml of a cola drink, 4 times a day (8h00, 12h00, 16h00 and 20h00). Immediately after the immersions, no treatment was performed in 4 specimens (ERO), 4 other specimens were immediately brushed (0 min) using a fluoride dentifrice and the device was replaced into the mouth. After 60 min, the other 4 specimens were brushed. In the second phase, the procedures were repeated but, after the immersions, the volunteers stimulated the salivary flow rate by chewing a sugar-free gum for 30 min. Enamel superficial alterations of all specimens were then evaluated using a scanning electron microscope. Enamel prism core dissolution was seen on the surfaces submitted to erosion, while on those submitted to erosion and to abrasion (both at 0 and 60 min) a more homogeneous enamel surface was observed, probably due to the removal of the altered superficial prism layer. For all the other variables - enamel substrate and salivary stimulation -, the microscopic pattern of the enamel specimens was similar.
Resumo:
The objective of this study was to assess the salivary residual effect of fluoride dentifrice on human enamel subjected to an erosive challenge. This crossover in situ study was performed in two phases (A and B), involving ten volunteers. In each phase, they wore acrylic palatal appliances, each containing 3 human enamel blocks, during 7 days. The blocks were subjected to erosion by immersion of the appliances in a cola drink for 5 minutes, 4 times a day. Dentifrice was used to brush the volunteers’ teeth, 4 times a day, during 1 minute, before the appliance was replaced into the mouth. In phases A and B the dentifrices used had the same formulation, except for the absence (PD) or presence (FD) of fluoride, respectively. Enamel alterations were determined using profilometry, microhardness (%SMHC), acid- and alkali-soluble F analysis. The data were tested using ANOVA (p < 0.05). The concentrations (mean ± SD) of alkali- and acid-soluble F (µgF/cm²) were, respectively, PD: 1.27ª ± 0.70/2.24A ± 0.36 and FD: 1.49ª ± 0.44/2.24A ± 0.67 (p > 0.05). The mean wear values (± SD, µm) were PD: 3.63ª ± 1.54 and FD: 3.54ª ± 0.90 (p > 0.05). The mean %SMHC values (± SD) were PD: 89.63ª ± 4.73 and FD: 87.28ª ± 4.01 (p > 0.05). Thus, we concluded that the residual fluoride from the fluoride-containing dentifrice did not protect enamel against erosion.
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Among the different properties that influence bone apposition around implants, the chemical or biochemical composition of implant surface may interfere on its acceptance by the surrounding bone. The aim of this study was to investigate if a biofunctionalization of implant surface influences the bone apposition in a dog model and to compare it with other surfaces, such as a microstructured created by the grit-blasting/acid-etching process. Eight young adult male mongrel dogs had the bilateral mandibular premolars extracted and each one received 6 implants after 12 weeks, totaling 48 implants in the experiment. Four groups of implants were formed with the same microrough topography with or without some kind of biofunctionalization treatment. After histomorphometric analysis, it was observed that the modified microstructured surface with a "low concentration of the bioactive peptide" provided a higher adjacent bone density (54.6%) when compared to the other groups (microstructured + HA coating = 46.0%, microstructured only = 45.3% and microstructured + "high concentration of the bioactive peptide" = 40.7%), but this difference was not statistically significant. In conclusion, biofunctionalization of the implant surface might interfere in the bone apposition around implants, especially in terms of bone density. Different concentrations of bioactive peptide lead to different results.
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Adjunctive therapeutic strategies that modulate the inflammatory mediators can play a significant role in periodontal therapy. In this double-blind, placebo-controlled study, 60 subjects diagnosed as periodontitis patients were evaluated for 28 days after periodontal treatment combined with selective cyclooxygenase-2 (COX-2) inhibitor. The experimental group received scaling and root planning (SRP) combined with the Loxoprofen antiinflammatory drug (SRP+Loxoprofen). The control group received SRP combined with placebo (SRP+placebo). Plaque index (PI), probing pocket depth (PD) and bleeding on probing (BOP) were monitored with an electronic probe at baseline and after 14 and 28 days. Both groups displayed clinical improvement in PD, PI and BOP. They also showed statistically similar values (p>0.05) of PD reduction on day 14 (0.4 mm) and on day 28 (0.6 mm). At the baseline, few deeper sites (>7 mm) from SRP+Loxoprofen group were responsible and most PD reduction was observed after 14 days (p<0.05). The percentage of remaining deep pockets (>7 mm) after 14 days in the SRP+Loxoprofen group was significantly lower (p<0.05) than in the SRP+placebo group. Loxoprofen presents potential effect as an adjunct of periodontal disease treatment, but long-term clinical trials are necessary to confirm its efficacy.