823 resultados para An ESRC Qualitative Longitudinal Study
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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In this paper, we report a detailed structural and electronic characterization of PbMoO4 crystals by using a conventional hydrothermal (CH) method. The samples were characterized by X-ray diffraction (XRD), Fourier transform Raman (FT-Raman), field-emission gun scanning electron microscopy (FEG-SEM) and photoluminescence (PL) measurements. In addition, first-principles quantum mechanical calculations based on the density functional theory were employed in order to understand the band structure and density of states for the PbMoO4. Analysis of both theoretical and experimental results allows to rationalize the role of order-disorder effects in the observed green PL emissions in these ordered powders.
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Aim: To demonstrate the magnitude and direction of skeletal changes in the maxilla and mandible during and after the use of bionator, as well as their rotations. Methods: Partial superimposition on the maxilla and mandible on the metallic implants and total superimposition on the cranial base were performed at three periods, T1 before bionator therapy, T2 after bionator therapy, and T3 5.68 years after T2. Results: There was total clockwise maxillary rotation and counterclockwise mandibular rotation, in the North American technique, throughout the study period, as well as extensive remodeling on the condylar region, especially in vertical direction and on the gonial region in horizontal direction. Conclusions: The total maxillary rotation seemed to be significantly affected by therapy than the mandible. There was a clear change in the direction of condylar remodeling compared to the period of bionator therapy and posterior bionator therapy. Considering the entire study period, it was observed that intra-matrix rotation of the maxilla and mandible masked their total rotation, causing minimum changes in the matrix rotation.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Objective: A morphological and ultra-structural study of copper vapor laser (λ = 510.6 nm) effects on enamel and dentine was performed to show the effects of this radiation. Methods: A total of 15 human molars were cut in half; 15 pieces were separated for irradiation on enamel and 15 for dentine. These two groups were further divided into five experimental groups, including a control group, comprised of three half-sections each, irradiated by a CVL laser with a power of 7 W, a repetition rate of 15,000 pulses/sec and exposed at 500, 600, and 800 msec and 1 sec irradiation times with a 5-sec interval between irradiations. Results: In an ultra-structural SEM exam, we observed that on the enamel surfaces irradiated for 1 sec there was morphological alteration that consisted of catering, flaking, and melting on the surfaces. There was no alteration for the other exposure times. On the dentine teeth irradiated for 1 sec, we observed an evident ultra-structural alteration of melted tissue and loss of morphological characteristics. In the dentine group irradiated by 800 msec, we observed ablation and a partial loss of morphological characteristics. In the dentine groups irradiated by 500 and 600 msec, no alteration was observed. Conclusions: The results showed that irradiation with CVL promoted morphologic changes in the enamel as well as in the dentine and demonstrated a need for future studies in order to establish a safe protocol for further use in the odontological practice.
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The electronic stopping cross section (SCS) of Al2O3 for proton beams is studied both experimentally and theoretically. The measurements are made for proton energies from 40 keV up to 1 MeV, which cover the maximum stopping region, using two experimental methods, the transmission technique at low energies (similar to 40-175 keV) and the Rutherford backscattering at high energies (approximate to 190-1000 keV). These new data reveal an increment of 16% in the SCS around the maximum stopping with respect to older measurements. The theoretical study includes electronic stopping power calculations based on the dielectric formalism and on the transport cross section (TCS) model to describe the electron excitations of Al2O3. The non-linear TCS calculations of the SCS for valence electrons together with the generalized oscillator strengths (GOS) model for the core electrons compare well with the experimental data in the whole range of energies considered.
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Spatial orientation in relation to the gravitational axis is significantly important for the maintenance of the posture, gait and for most of the human's motor activities. The subjective visual vertical exam evaluates the individual's perception of vertical orientation. Objectives: The aims of this study were (1) to develop a virtual system to evaluate the subjective visual vertical exam, (2) to provide a simple tool to clinical practice and (3) to assess the subjective visual vertical values of h ealthy subjects using the new software. Study Design: observational cross-sectional study. Methods: Thirty healthy volunteers performed the subjective visual vertical exam in both static and dynamic conditions. The exam consisted in adjusting a virtual line in the vertical position using the computer mouse. For the static condition, the virtual line was projected in a white background. For the dynamic condition, black circles rotated in clockwise or counterclockwise directions. Six measurements were taken and the mean deviations in relation to the real vertical calculated. Results: The mean values of subjective visual vertical measurements were: static -0.372 degrees; +/- 1.21; dynamic clockwise 1.53 degrees +/- 1.80 and dynamic counterclockwise -1.11 degrees +/- 2.46. Conclusion: This software showed to be practical and accurate to be used in clinical routines.
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Phenomenology is a critical component of autobiographical memory retrieval. Some memories are vivid and rich in sensory details whereas others are faded; some memories are experienced as emotionally intense whereas others are not. Sutin and Robins (2007) identified 10 dimensions in which a memory may vary—i.e., Vividness, Coherence, Accessibility, Sensory Details, Emotional Intensity, Visual Perspective, Time Perspective, Sharing, Distancing, and Valence—and developed a comprehensive psychometrically sound measure of memory phenomenology, the Memory Experiences Questionnaire (MEQ). Phenomenology has been linked to underlining stable dispositions—i.e. personality, as well as to a variety of positive/negative psychological outcomes—well-being and life satisfaction, depression and anxiety, among others. Using the MEQ, a cross-sectional and a longitudinal study were conducted on a large sample of American and Italian adults. In both studies, participants retrieved two ‘key’ personal memories, a Turning Point and a Childhood Memory, and rated the affect and phenomenology of each memory. Participants also completed self-reported measures of personality (i.e. Neuroticism and Conscientiousness), and measures of depression, well-being and life satisfaction. The present research showed that phenomenological ratings tend (a) to cross-sectionally increase across adulthood (Study 1), and (b) to be moderately stable over time, regardless the contents of the memories (Study 2). Interrelations among memory phenomenology, personality and psychological outcome variables were also examined (Study 1 and Study 2). In particular, autobiographical memory phenomenology was proposed as a dynamic expression of personality functioning that partially explains adaptive/maladaptive psychological outcomes. In fact, the findings partially supported the hypothesized mediating effect of phenomenology on the personality association with psychological outcomes. Implications of the findings are discussed proposing future lines of research. In particular, the need for more longitudinal studies is highlighted, along with the combined application of both self-report questionnaires and narrative measures.
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Background: cognitive impairment is one of the non motor features widely descripted in parkinsonian syndrome, it has been related to the motor characteristics of the parkinsonian syndrome, associated with neuropsychiatric dysfunction and the characteristic sleep and autonomic features. It has been shown to be highly prevalent at all disease stages and to contribute significantly to disability. Objectives: aim of this study is to evaluate longitudinally the cognitive and behavioral characteristics of patients with a parkinsonian syndrome at onset; to describe the cognitive and behavioral characteristics of each parkinsonian syndrome; to define in PD patients at onset the presence of MCI or Parkinson disease dementia; to correlate the cognitive and behavioral characteristics with the features of the parkinsonian syndrome and with the associated sleep and autonomic features. Results: we recruited 55 patients, 22 did not present cognitive impairment both at T0 and at T1. 18 patients presented a progression of cognitive impairment. Progressive cognitively impaired patients were older and presented the worst motor phenotype. Progression of cognitive impairment was not associated to sleep and autonomic features. Conclusion: the evaluation of cognitive impairment could not be useful as a predictor of a correct diagnosis but each non motor domain will help to clarify and characterize the motor syndrome. The diagnosis of parkinsonian disorders lies in building a clinical profile in conjunction with other clinical characteristics such as mode of presentation, disease progression, response to medications, sleep and autonomic features.
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Background-Amyloidotic cardiomyopathy (AC) can mimic true left ventricular hypertrophy (LVH), including hypertrophic cardiomyopathy (HCM) and hypertensive heart disease (HHD). We assessed the diagnostic value of combined electrocardiographic/echocardiographic indexes to identify AC among patients with increased echocardiographic LV wall thickness due to either different etiologies of amyloidosis or HCM or HHD. Method-First, we studied 469 consecutive patients: 262 with biopsy/genetically proven AC (with either AL or transthyretin (TTR)-related amyloidosis); 106 with HCM; 101 with HHD. We compared the diagnostic performance of: low QRS voltage, symmetric LVH, low QRS voltage plus interventricular septal thickness >1.98 cm, Sokolow index divided by the cross-sectional area of LV wall, Sokolow index divided by body surface area indexed LV mass (LVMI), Sokolow index divided by LV wall thickness, Sokolow index divided by (LV wall/height^2.7); peripheral QRS score divided by LVMI, Peripheral QRS score divided by LV wall thickness, Peripheral QRS score divided by LV wall thickness indexed to height^2.7, total QRS score divided by LVMI, total QRS score divided by LV wall thickness; total QRS score divided by (LV wall/height^2.7). We tested each criterion, separately in males and females, in the following settings: AC vs. HCM+HHD; AC vs. HCM; AL vs. HCM+HHD; AL vs. HCM; TTR vs. HCM+HHD; TTR vs. HCM. Results-Low QRS voltage showed high specificity but low sensitivity for the identification of AC. All the combined indexes had a higher diagnostic accuracy, being total QRS score divided by LV wall thickness or by LVMI associated with the best performances and the largest areas under the ROC curve. These results were validated in 298 consecutive patients with AC, HCM or HHD. Conclusions-In patients with increased LV wall thickness, a combined ECG/ echocardiogram analysis provides accurate indexes to non-invasively identify AC. Total QRS score divided by LVMI or LV wall thickness offers the best diagnostic performance.
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Incomplete endothelialization has been found to be associated with late stent thrombosis, a rare but devastating phenomenon, more frequent after drug-eluting stent implantation. Optical coherence tomography (OCT) has 10 times greater resolution than intravascular ultrasound and thus appears to be a valuable modality for the assessment of stent strut coverage. The LEADERS trial was a multi-centre, randomized comparison of a biolimus-eluting stent (BES) with biodegradable polymer with a sirolimus-eluting stent (SES) using a durable polymer. This study sought to evaluate tissue coverage and apposition of stents using OCT in a group of patients from the randomized LEADERS trial.
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Background Current knowledge about risk factors promoting hypertensive crisis originates from retrospective data. Therefore, potential risk factors of hypertensive crisis were assessed in a prospective longitudinal study. Methods Eighty-nine patients of the medical outpatient unit at the University Hospital of Bern (Bern, Switzerland) with previously diagnosed hypertension participated in this study. At baseline, 33 potential risk factors were assessed. All patients were followed-up for the outcome of hypertensive crisis. Cox regression models were used to detect relationships between risk factors and hypertensive crisis (defined as acute rise of systolic blood pressure (BP) ≥200mmHg and/or diastolic BP ≥120mmHg). Results The mean duration of follow-up was 1.6 ± 0.3 years (range 1.0–2.4 years). Four patients (4.5%) were lost to follow-up. Thirteen patients (15.3%) experienced hypertensive crisis during follow-up. Several potential risk factors were significantly associated with hypertensive crisis: female sex, higher grades of obesity, the presence of a hypertensive or coronary heart disease, the presence of a somatoform disorder, a higher number of antihypertensive drugs, and nonadherence to medication. As measured by the hazard ratio, nonadherence was the most important factor associated with hypertensive crisis (hazard ratio 5.88, 95% confidence interval 1.59–21.77, P < 0.01). Conclusions This study identified several potential risk factors of hypertensive crisis. Results of this study are consistent with the hypothesis that improvement of medical adherence in antihypertensive therapy would help to prevent hypertensive crises. However, larger studies are needed to assess potential confounding, other risk factors and the possibility of interaction between predictors.
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Background Routine chlamydia screening is a recommended preventive intervention for sexually active women aged ≤25 years in the U.S. but rates of regular uptake are not known. Purpose This study aimed to examine rates of annual chlamydia testing and factors associated with repeat testing in a population of U.S. women. Methods Women aged 15–25 years at any time from January 1, 2002, to December 31, 2006 who were enrolled in 130 commercial health plans were included. Data relating to chlamydia tests were analyzed in 2009. Chlamydia testing rates (per 100 woman-years) by age and rates of repeated annual testing were estimated. Poisson regression was used to examine the effects of age and previous testing on further chlamydia testing within the observation period. Results In total, 2,632,365 women were included. The chlamydia testing rate over the whole study period was 13.6 per 100 woman years after adjusting for age-specific sexual activity; 8.5 (95% CI=6.0, 12.3) per 100 woman-years in those aged 15 years; and 17.7 (95% CI=17.1, 18.9) in those aged 25 years. Among women enrolled for the entire 5-year study period, 25.9% had at least one test but only 0.1% had a chlamydia test every year. Women tested more than once and older women were more likely to be tested again in the observation period. Conclusions The low rates of regular annual chlamydia testing do not comply with national recommendations and would not be expected to have a major impact on the control of chlamydia infection at the population level.