871 resultados para delayed matching to sample
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Do capuchin monkeys respond to photos as icons? Do they discriminate photos of capuchin monkeys' faces? Looking for answers to these questions we trained three capuchin monkeys in simple and conditional discrimination tasks and tested the discriminations when comparison stimuli were partially covered. Three capuchin monkeys experienced in simultaneous simple discrimination and IDMTS were trained with repeated shifts of simple discriminations (RSSD), with four simultaneous choices, and IDMTS (1 s delay, 4 choices) with pictures of known capuchins monkeys' faces. All monkeys did discriminate the pictures in both procedures. Performances in probes with partial masks with one fourth of the stimulus hidden were consistent with baseline level. Errors occurred when a picture similar to the correct one was available among the comparison stimuli, when the covered part was the most distinct, or when pictures displayed the same monkey. Capuchin monkeys do match pictures of capuchin monkeys' faces to the sample. The monkeys treated different pictures of the same monkey as equivalent, suggesting that they respond to the pictures as icons, although this was not true to pictures of other monkeys. Subsequent studies may bring more evidence that capuchin monkeys treat pictures as depictions of real scenes.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The aim of the present study was to evaluate the microtensile bond strength to dentin (ATBS) of two total-etching adhesives applied with delays of 1-30 s for curing. Fifty extracted molar teeth were used. Occlusal enamel was sectioned to expose flat dentin surface, which was further polished with 600-grit paper for smear layer standardization. The specimens were divided into two groups, G1: Single Bond total-etching adhesive (SB), and G2: Prime & Bond NT total-etching adhesive (PB). Each group was further divided into 5 subgroups according to the delayed light-cure initiation after the adhesive systems application (n=5): Subgroup 1s - 1 s; Subgroup 5s -5 s; Subgroup 10s - 10 s; Subgroup 20s - 20 s; Subgroup 30s - 30 s. Composite resin cones 5 mm height and 10 mm in diameter were fabricated. Specimens were stored in distilled water at 37 degrees C for 24 h and sectioned to obtain 1 x 1 mm(2) transversal specimens. Specimens were thermocycled and mu TBS was measured. Data were submitted to two-way ANOVA (AdhesiveXDelay time) and Tukey's test. The level of significance was set at 5%. The results in mean MPa(+/- SD) for interaction between adhesive and delay time were: PB/1s - 23.82 +/- 2.54a; SB/5s - 19.52 +/- 2.67b; PB/5s - 18.56 +/- 3.06bc; SB/1s - 15.49 +/- 2.69cd; SB/20s - 16.33 +/- 2.55d; SB/10s - 13.88 +/- 1.67d; PB/10s - 11.04 +/- 1.28e; PB/30s - 10.89 +/- 1.31e; PB/20s - 10.24 +/- 2.33e; SB/30s - 9.19 +/- 1.91e. It was concluded that light-cure initiation timing of total-etching adhesives interferes negatively with mu TBS to dentin. (C) 2014 Elsevier Ltd. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The impact of peritoneal dialysis modality on patient survival and peritonitis rates is not fully understood, and no large-scale randomized clinical trial (RCT) is available. In the absence of a RCT, the use of an advanced matching procedure to reduce selection bias in large cohort studies may be the best approach. The aim of this study is to compare automated peritoneal dialysis (APD) and continuous ambulatory peritoneal dialysis (CAPD) according to peritonitis risk, technique failure and patient survival in a large nation-wide PD cohort. This is a prospective cohort study that included all incident PD patients with at least 90 days of PD recruited in the BRAZPD study. All patients who were treated exclusively with either APD or CAPD were matched for 15 different covariates using a propensity score calculated with the nearest neighbor method. Clinical outcomes analyzed were overall mortality, technique failure and time to first peritonitis. For all analysis we also adjusted the curves for the presence of competing risks with the Fine and Gray analysis. After the matching procedure, 2,890 patients were included in the analysis (1,445 in each group). Baseline characteristics were similar for all covariates including: age, diabetes, BMI, Center-experience, coronary artery disease, cancer, literacy, hypertension, race, previous HD, gender, pre-dialysis care, family income, peripheral artery disease and year of starting PD. Mortality rate was higher in CAPD patients (SHR1.44 CI95%1.21-1.71) compared to APD, but no difference was observed for technique failure (SHR0.83 CI95%0.69-1.02) nor for time till the first peritonitis episode (SHR0.96 CI95%0.93-1.11). In the first large PD cohort study with groups balanced for several covariates using propensity score matching, PD modality was not associated with differences in neither time to first peritonitis nor in technique failure. Nevertheless, patient survival was significantly better in APD patients.
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Background: Studies on functional capacity in community-dwelling older people have shown associations between declines in instrumental activities of daily living (IADL) and several factors. Among these, age has been the most consistently related to functional capacity independent of other variables. We aimed at evaluating the performance of a sample of healthy and cognitively intact Brazilian older people on activities of daily living and to analyze its relation to social-demographic variables. Methods: We conducted a secondary analysis of data collected for previous epidemiological studies with community-dwelling subjects aged 60 years or more. We selected subjects who did not have dementia or depression, and with no history of neurological diseases, heart attack, HIV, hepatitis or arthritis (n = 1,111). Functional capacity was assessed using the Brazilian version of the Older American Resources and Services Questionnaire (BOMFAQ). ADL performance was analyzed according to age, gender, education, and marital status (Pearson's chi(2), logistic regression). Results: IADL difficulties were present in our sample, especially in subjects aged 80 years or more, with lower levels of education, or widowed. The logistic regression analysis results indicated that "higher age" and "lower education" (p <= 0.001) remained significantly associated with IADL difficulty. Conclusions: Functional decline was present in older subjects even in the absence of medical conditions and cognitive impairment. Clinicians and researchers could benefit from knowing what to expect from older people regarding IADL performance in the absence of medical conditions.
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A thin-layer electrochemical flow cell coupled to capillary electrophoresis with contactless conductivity detection (EC-CE-(CD)-D-4) was applied for the first time to the derivatization and quantification of neutral species using aliphatic alcohols as model compounds. The simultaneous electrooxidation of four alcohols (ethanol, 1-propanol, 1-butanol, and 1-pentanol) to the corresponding carboxylates was carried out on a platinum working electrode in acid medium. The derivatization step required 1 min at 1.6 V vs. Ag/AgCl under stopped flow conditions, which was preceded by a 10 s activation at 0 V. The solution close to the electrode surface was then hydrodynamically injected into the capillary, and a 2.5 min electrophoretic separation was carried out. The fully automated flow system operated at a frequency of 12 analyses per hour. Simultaneous determination of the four alcohols presented detection limits of about 5 x 10(-5) mol As a practical application with a complex matrix, ethanol concentrations were determined in diluted pale lager beer and in nonalcoholic beer. No statistically significant difference was observed between the EC-CE-(CD)-D-4 and gas chromatography with flame ionization detection (GC-FID) results for these samples. The derivatization efficiency remained constant over several hours of continuous operation with lager beer samples (n = 40).
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Clinicians frequently have to decide when dialysis should be initiated and which modality should be used to support kidney function in critically ill patients with acute kidney injury. In most instances, these decisions are made based on the consideration of a variety of factors including patient condition, available resources and prevailing local practice experience. There is a wide variation worldwide in how these factors influence the timing of initiation and the utilization of various modalities. In this article, we review the therapeutic goals of renal support and the relative advantages and shortcomings of different dialysis techniques. We describe strategies for matching the timing of initiation to the choice of modality to individualize renal support in intensive care unit patients. Copyright (C) 2012 S. Karger AG, Basel
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Objective. To evaluate the efficacy of a 3-month exercise training program in counteracting the chronotropic incompetence and delayed heart rate recovery in patients with systemic lupus erythematosus (SLE). Methods. A 12-week randomized trial was conducted. Twenty-four inactive SLE patients were randomly assigned into 2 groups: trained (T; n = 15, 3-month exercise program) and nontrained (NT; n = 13). A sex-, body mass index-, and age-matched healthy control (C) group (n = 8) also underwent the exercise program. Subjects were assessed at baseline and at 12 weeks after training. Main measurements included the chronotropic reserve (CR) and the heart rate (HR) recovery (Delta HRR) as defined by the difference between HR at peak exercise and at both the first (Delta HRR1) and second (Delta HRR2) minutes after the exercise test. Results. Neither the NT SLE patients nor the C group presented any change in the CR or in Delta HRR1 and Delta HRR2 (P > 0.05). The exercise training program was effective in promoting significant increases in CR (P = 0.007, effect size [ES] 1.15) and in Delta HRR1 and Delta HRR2 (P = 0.009, ES 1.12 and P = 0.002, ES 1.11, respectively) in the SLE T group when compared with the NT group. Moreover, the HR response in SLE patients after training achieved parameters comparable to the C group, as evidenced by the analysis of variance and by the Z score analysis (P > 0.05, T versus C). Systemic Lupus Erythematosus Disease Activity Index scores remained stable throughout the study. Conclusion. A 3-month exercise training program was safe and capable of reducing the chronotropic incompetence and the delayed Delta HRR observed in physically inactive SLE patients.
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The influence of test method factors (notch shape, square or angular, and pre-cracking method, by tapping onto or pressing a razor blade) on the results obtained in plane strain fracture toughness test according to standard ASTM D5045 using SENB specimens made of a commercial PMMA resin were investigated. Results were analyzed quantitatively by comparing the obtained K-IC values and qualitatively by observing their effect on the Moire fringes observed using photoelasticity, showing that, at 95% significance level, the K-IC values are affected by the pre-cracking method, with the most conservative value being obtained when natural pre-cracks were introduced by tapping onto a razor blade (K-IC = 1.15 +/- 0.11 MPa.m(0.5)). This correlates with a perturbation in the stress field close to the pre-crack tip observed in the photoelasticity test sample when it was introduced by pressing the razor blade. Surprisingly, notch geometry only slightly affects the results. (C) 2012 Elsevier Ltd. All rights reserved.
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Respiratory type-IV hypersensitivity reactions due to corticosteroids is a rare phenomenon. We describe two such cases. The first is a 37- year-old atopic woman who developed labial angioedema and nasal itching after the use of budesonide nasal spray. A month later, after the first puffs of a formoterol/budesonide spray prescribed for asthma, she noticed symptoms of tongue and oropharyngeal itching and redness with subsequent dysphagia, labial and tongue angioedema, and facial oedema. The second is a 15-year-old non-atopic woman who reported pruritic eruptions around the nostrils after using a budesonide nasal spray. A year later she presented with nasal pruritus with intense congestion and labial and facial oedema after using the same spray. Both patients were evaluated with patch-tests using the commercial T.R.U.E. test, a budesonide solution, and corticosteroid creams. Test evaluation was performed at 48 and 96 hours. In both patients, patch tests were positive to budesonide (++) on the second day. The first patient also had a positive (+) reaction to tixocortol-21-pivalate. All the other patch tests were negative. Clinicians should be aware that hypersensitivity reactions may occur during the use of nasal or inhaled corticosteroids.
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This paper describes informatics for cross-sample analysis with comprehensive two-dimensional gas chromatography (GCxGC) and high-resolution mass spectrometry (HRMS). GCxGC-HRMS analysis produces large data sets that are rich with information, but highly complex. The size of the data and volume of information requires automated processing for comprehensive cross-sample analysis, but the complexity poses a challenge for developing robust methods. The approach developed here analyzes GCxGC-HRMS data from multiple samples to extract a feature template that comprehensively captures the pattern of peaks detected in the retention-times plane. Then, for each sample chromatogram, the template is geometrically transformed to align with the detected peak pattern and generate a set of feature measurements for cross-sample analyses such as sample classification and biomarker discovery. The approach avoids the intractable problem of comprehensive peak matching by using a few reliable peaks for alignment and peak-based retention-plane windows to define comprehensive features that can be reliably matched for cross-sample analysis. The informatics are demonstrated with a set of 18 samples from breast-cancer tumors, each from different individuals, six each for Grades 1-3. The features allow classification that matches grading by a cancer pathologist with 78% success in leave-one-out cross-validation experiments. The HRMS signatures of the features of interest can be examined for determining elemental compositions and identifying compounds.
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Proper sample size estimation is an important part of clinical trial methodology and closely related to the precision and power of the trial's results. Trials with sufficient sample sizes are scientifically and ethically justified and more credible compared with trials with insufficient sizes. Planning clinical trials with inadequate sample sizes might be considered as a waste of time and resources, as well as unethical, since patients might be enrolled in a study in which the expected results will not be trusted and are unlikely to have an impact on clinical practice. Because of the low emphasis of sample size calculation in clinical trials in orthodontics, it is the objective of this article to introduce the orthodontic clinician to the importance and the general principles of sample size calculations for randomized controlled trials to serve as guidance for study designs and as a tool for quality assessment when reviewing published clinical trials in our specialty. Examples of calculations are shown for 2-arm parallel trials applicable to orthodontics. The working examples are analyzed, and the implications of design or inherent complexities in each category are discussed.