951 resultados para Anxiety Sensitivity Index - Revised
Sensitivity to noise and ergodicity of an assembly line of cellular automata that classifies density
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We investigate the sensitivity of the composite cellular automaton of H. Fuks [Phys. Rev. E 55, R2081 (1997)] to noise and assess the density classification performance of the resulting probabilistic cellular automaton (PCA) numerically. We conclude that the composite PCA performs the density classification task reliably only up to very small levels of noise. In particular, it cannot outperform the noisy Gacs-Kurdyumov-Levin automaton, an imperfect classifier, for any level of noise. While the original composite CA is nonergodic, analyses of relaxation times indicate that its noisy version is an ergodic automaton, with the relaxation times decaying algebraically over an extended range of parameters with an exponent very close (possibly equal) to the mean-field value.
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The stomatal density and index in compressed leaves of Glossopteris communis from two different roof shales from the Lower Permian in Parana Basin, Brazil (Western Gondwana) have been investigated to test the possible relationship with modeled global changes in atmospheric CO(2) during the Phanerozoic. The obtained parameters show that the genus Glossopteris from the Cool Temperate biome can be used as CO(2) -proxy, despite the impossibility of being compared with living relatives or equivalents. When confronted with already published data for the Tropical Summer Wet biome, the present results confirm the detection of low levels of atmospheric CO(2) during the Early Permian, as predicted by the modeled curve. Nevertheless, the lower stomatal numbers detected at the climax of the coal interval (Faxinal Coalfield, Sakmarian) when compared to the higher ones obtained in leaves from a younger interval (Figueira Coalfield, Artinskian) could be attributed to temporarily high levels of atmospheric CO(2). Therefore, the occurrence of an extensive peat generating event at the southern part of the basin and subsequent greenhouse gases emissions from this environment may have been enough to reverse regionally and temporarily the reduction trend in atmospheric CO(2). Additionally, the Faxinal flora is preserved in a tonstein layer, which is a record of volcanic activity that could also cause a rise in atmospheric CO(2). During the Artinskian, the scarce generation of peat mires, as revealed by the occurrence of thin and discontinuous coal layers, and the lack of volcanism evidence would be insufficient to affect the general low CO(2) trend.
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A green and highly sensitive analytical procedure was developed for the determination of free chlorine in natural waters, based on the reaction with N,N-diethyl-p-phenylenediamine (DPD). The flow system was designed with solenoid micro-pumps in order to improve mixing conditions by pulsed flows and to minimize reagent consumption as well as waste generation. A 100-cm optical path flow cell based on a liquid core waveguide was employed to increase sensitivity. A linear response was observed within the range 10.0 to 100.0 mu g L(-1), with the detection limit, coefficient of variation and sampling rate estimated as 6.8 mu g (99.7% confidence level), 0.9% (n = 20) and 60 determinations per hour, respectively. The consumption of the most toxic reagent (DPD) was reduced 20,000-fold and 30-fold in comparison to the batch method and flow injection with continuous reagent addition, respectively. The results for natural and tap water samples agreed with those obtained by the reference batch spectrophotometric procedure at the 95% confidence level. (C) 2010 Elsevier By. All rights reserved.
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Purpose: The objective of this Pilot Study was to determine pain characteristics of pregnant women immediately before and after childbirth by vaginal delivery and to compare them with the pain intensity reported by physicians. Methods: We evaluated 20 Brazilian women between September and December 2007 with the WHOQOL-Bref instrument, VAS, McGill Pain Questionnaire, and Anxiety Adapted Scale. We interviewed the obstetrician with the VAS about the patient`s pain, Data were analyzed with the chi-square test. Results: Mean age was 22.35 years (SD = 6.24, range 15-39 years). It was necessary to use oxytocin in 15 (75%) patients, which had no correlation with anxiety degree. Higher intensity of pain (p < 0.05) and higher anxiety index (p < 0.05) were more common in women in the first pregnancy. Conclusions: Higher pain intensity was associated with higher anxiety levels (p < 0.05). Around half of the obstetricians` VAS scores were lower than the VAS scores of women, and probably pain at labor was underestimated and not controlled. Higher indices of anxiety and pain were associated, and were more frequent in women in the first pregnancy.
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We evaluated the reliability and validity of a Brazilian-Portuguese version of the Epilepsy Medication Treatment Complexity Index (EMTCI). Interrater reliability was evaluated with the intraclass correlation coefficient (ICC), and validity was evaluated by correlation of mean EMTCI scores with the following variables: number of antiepileptic drugs (AEDs), seizure control, patients` perception of seizure control, and adherence to the therapeutic regimen as measured with the Morisky scale. We studied patients with epilepsy followed in a tertiary university-based hospital outpatient clinic setting, aged 18 years or older, independent in daily living activities, and without cognitive impairment or active psychiatric disease. ICCs ranged from 0.721 to 0.999. Mean EMTCI scores were significantly correlated with the variables assessed. Higher EMTCI scores were associated with an increasing number of AEDs, uncontrolled seizures, patients` perception of lack of seizure control, and poorer adherence to the therapeutic regimen. The results indicate that the Brazilian-Portuguese EMTCI is reliable and valid to be applied clinically in the country. The Brazilian-Portuguese EMTCI version may be a useful tool in developing strategies to minimize treatment complexity, possibly improving seizure control and quality of life in people with epilepsy in our milieu. (C) 2011 Elsevier Inc. All rights reserved.
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The objective of this study was to validate the Piper Fatigue Scale-Revised (PFS-R) for use in Brazilian culture. Translation of the PFS-R into Portuguese and validity and reliability tests were performed. Convenience samples in Brazil we as follows: 584 cancer patients (mean age 57 +/- 13 years; 51.3% female); 184 caregivers (mean age 50 +/- 12.7 years; 65.8% female); and 189 undergraduate nursing students (mean age 21.6 +/- 2.8 years; 96.2% female); Instruments used were as follows: Brazilian PFS, Beck Depression Inventory (BDI), and Karnofsky Performance Scale (KPS). The 22 items of the Brazilian PFS loaded well (factor loading > 0.35) on three dimensions identified by factor analysis (behavioral, affective, and sensorial-psychological). These dimensions explained 65% of the variance. Internal consistency reliability was very good (Cronbach`s alpha ranged from 0.841 to 0.943 for the total scale and its dimensions). Cancer patients and their caregivers completed the Brazilian PFS twice for test-retest reliability and results showed good stability (Pearson`s r a parts per thousand yenaEuro parts per thousand 0,60, p < 0,001). Correlations among the Brazilian PFS and other scales were significant, in hypothesized directions, and mostly moderate contributing to divergent (Brazilian PFS x KPS) and convergent validity (Brazilian PFS x BDI). Mild, moderate, and severe fatigue in patients were reported by 73 (12.5%), 167 (28.6%), and 83 (14.2%), respectively. Surprisingly, students had the highest mean total fatigue scores; no significant differences were observed between patients and caregivers showing poor discriminant validity. While the Brazilian PFS is a reliable and valid instrument to measure fatigue in Brazilian cancer patients, further work is needed to evaluate the discriminant validity of the scale in Brazil.
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Background: Studies have shown that the autonomic dysfunction accompanied by impaired baroreflex sensitivity was associated with higher mortality. However, the influence of decreased baroreflex sensitivity on cardiac function, especially in diastolic function, is not well understood. This study evaluated the morpho-functional changes associated with baroreflex impairment induced by chronic sinoaortic denervation (SAD). Methods and Results: Animals were divided into sinoaortic denervation (SAD) and control (C) groups. Baroreflex sensitivity was evaluated by tachycardic and bradycardic responses, induced by vasoactive drugs. Cardiac function was studied by echocardiography and by left ventricle (LV) catheterization. LV collagen content and the expression of regulatory proteins involved in intracellular Ca(2+) homeostasis were quantified. Results showed higher LV mass in SAD versus C animals. Furthermore, an increase in deceleration time of E-wave in the SAD versus the C group (2.14 +/- 0.07 ms vs 1.78 +/- 0.03 ms) was observed. LV end-diastolic pressure was increased and the minimum dP/dt was decreased in the SAD versus the C group (12 +/- 1.5 mm Hg vs 5.3 +/- 0.2 mm Hg and 7,422 +/- 201 vs 4,999 +/- 345 mm Hg/s, respectively). SERCA/NCX ratio was lower in SAD than in control rats. The same was verified in SERCA/PLB ratio. Conclusions: The results suggest that baroreflex dysfunction is associated with cardiac diastolic dysfunction independently of the presence of other risk factors. (J Cardiac Fail 2011;17:519-525)
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Background: The Burns Specific Health Scale-Revised (BSHS-R) is of easy application, can be self-administered, and it is considered a good scale to evaluate various important life aspects of burn victims. Objectives: To translate and culturally adapt the BSHS-R into the Brazilian-Portuguese language and to evaluate the internal consistency and convergent validity of the translated BSHS-R. Methods: The cultural adaptation of the BSHS-R included translation and back-translation, discussions with professionals and patients to ensure conceptual equivalence, semantic evaluation, and pre-test of the instrument. The Final Brazilian-Portuguese Version (FBPV) of the BSHS-R was tested on a group of 115 burn patients for internal consistency and validity of construct (using the Rosenberg Self-Esteem Scale (RSES) and the Beck Depression Inventory (BDI)). Results: All values of Cronbach`s alpha were greater than. 8, demonstrating that the internal consistency of the FBPV was very high. Self-esteem was highly correlated with affect and body image (r = .59, p < .001), and with interpersonal relationships (T = .51, p < .001). Correlations between the domains of the FBPV and the BDI were all negative but larger in magnitude than the correlations with RSES. Depression was highly correlated with affect and body image (r = -77, p < .001), and with interpersonal relationships (r = -67, p < .001). Conclusions: The results showed that the adapted version of the BSHS-R into Brazilian-Portuguese fulfills the validity and reliability criteria required from an instrument of health status assessment for burn patients. (C) 2008 Elsevier Ltd and ISBI. All rights reserved.
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Purpose: The diagnosis of cancer and the treatment decisions associated with it may cause uncertainty, stress, and anxiety among parents. Emotional tensions can affect parents` relationships during the trajectory of the child`s cancer illness. We conducted an integrative review to examine the evidence related to the effects of childhood cancer on parents` relationships. Methods: An integrative literature search of studies published between 1997 and 2009 was conducted in the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Psychology Information (PsycINFO), PubMed, Scopus, CUIDEN, and Latin American and Caribbean Health Science Literature (LILACS). The key words used were neoplasms, child, marriage, spouses, family relations, and nursing. Articles were reviewed if the (a) topic addressed parents` relationships during childhood cancer; (b) participants were mothers, fathers, or both; (c) design was either qualitative or quantitative; (d) language was English, Portuguese, or Spanish; (e) date of publication was between January 1997 and October 2009; and (f) abstract was available. Results: Fourteen articles met the search criteria and were reviewed using Cooper`s framework for integrative reviews. Four themes emerged: (a) changes in the parents` relationship during the trajectory of the child`s illness; (b) difficulty in communication between couples; (c) gender differences in parental stress and coping; and (d) role changes. Conclusions and Implications: Findings revealed positive and negative changes in parents` relationships, communication, stress, and roles. Nurses need to assess the impact of cancer diagnosis and treatments on parent relationships, offer support and encouragement, and allow expression of feelings. Future research is needed to develop and test interventions that increase parents` potentials and strengthen relationships during the challenging trajectory of their children`s cancer and treatment. Clinical Relevance: The multiple sources of stress and uncertainty associated with a child`s cancer diagnosis and treatment affect parents` relationships. Difficulties in communication appear frequently in parents` relationship. Our findings may guide healthcare professionals in identifying parents at risk for developing conflicts, communication problems, and lack of alignment between parents that could interfere with providing optimal care for their child with cancer. Healthcare professionals may promote dialogue and encourage parents to express their feelings, seek mutual support, and establish a partnership in dealing with the child`s illness.
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Introduction To determine and compare thresholds of cutaneous sensitivity of lower extremities in diabetic patients with an ulcer on only one lower extremity Methods and Materials The study group included 20 patients with mean age of 61 6 and average time with diabetes of 12 4 years All patients were previously tested using Semmes-Weinstein monofilament 5 07 Sensitivity was evaluated using the two point discrimination test and the PSSD (TM) (Pressure-Specified Sensory Device) in order to assess touch thresholds in a quantitative manner, in g/mm(2) Three skin areas were tested hallux pulp, dorsum of foot and medial heel, including four tests 1 point static, 1 point moving, 2 points static and 2 points moving Results Mean 2 point discrimination distance in mm was higher in feet with ulcers, but the difference between extremities was only statistically significant for the hallux. With the PSSD (TM), all patients had higher pressure thresholds in feet with ulcers when compared with feet without ulcers, in all tests, with statistical significance Conclusion The PSSD (TM) was able to differentiate levels of sensation between extremities with and without ulcers in diabetic patients, with statistical significance
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This paper presents studies of cases in power systems by Sensitivity Analysis (SA) oriented by Optimal Power Flow (OPF) problems in different operation scenarios. The studies of cases start from a known optimal solution obtained by OPF. This optimal solution is called base case, and from this solution new operation points may be evaluated by SA when perturbations occur in the system. The SA is based on Fiacco`s Theorem and has the advantage of not be an iterative process. In order to show the good performance of the proposed technique tests were carried out on the IEEE 14, 118 and 300 buses systems. (C) 2010 Elsevier Ltd. All rights reserved.
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This paper proposes an approach of optimal sensitivity applied in the tertiary loop of the automatic generation control. The approach is based on the theorem of non-linear perturbation. From an optimal operation point obtained by an optimal power flow a new optimal operation point is directly determined after a perturbation, i.e., without the necessity of an iterative process. This new optimal operation point satisfies the constraints of the problem for small perturbation in the loads. The participation factors and the voltage set point of the automatic voltage regulators (AVR) of the generators are determined by the technique of optimal sensitivity, considering the effects of the active power losses minimization and the network constraints. The participation factors and voltage set point of the generators are supplied directly to a computational program of dynamic simulation of the automatic generation control, named by power sensitivity mode. Test results are presented to show the good performance of this approach. (C) 2008 Elsevier B.V. All rights reserved.
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This paper presents a new approach to the transmission loss allocation problem in a deregulated system. This approach belongs to the set of incremental methods. It treats all the constraints of the network, i.e. control, state and functional constraints. The approach is based on the perturbation of optimum theorem. From a given optimal operating point obtained by the optimal power flow the loads are perturbed and a new optimal operating point that satisfies the constraints is determined by the sensibility analysis. This solution is used to obtain the allocation coefficients of the losses for the generators and loads of the network. Numerical results show the proposed approach in comparison to other methods obtained with well-known transmission networks, IEEE 14-bus. Other test emphasizes the importance of considering the operational constraints of the network. And finally the approach is applied to an actual Brazilian equivalent network composed of 787 buses, and it is compared with the technique used nowadays by the Brazilian Control Center. (c) 2007 Elsevier Ltd. All rights reserved.
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The noise, vibration and harshness (NVH) performance of passenger vehicles strongly depends on the fluid-structure interaction between the air in the vehicle cavity and the sheet metal structure of the vehicle. Most of the noise and vibration problems related to this interaction come from resonance peaks of the sheet metal, which are excited by external forces (road, engine, and wind). A reduction in these resonance peaks can be achieved by applying bitumen damping layers, also called deadeners, in the sheet metal. The problem is where these deadeners shall be fixed, which is usually done in a trial-and-error basis. In this work, one proposes the use of embedded sensitivity to locate the deadeners in the sheet metal of the vehicle, more specifically in the vehicle roof. Experimental frequency response functions (FRFs) of the roof are obtained and the data are processed by adopting the embedded sensitivity method, thus obtaining the sensitivity of the resonance peaks on the local increase in damping due to the deadeners. As a result, by examining the sensitivity functions, one can find the optimum location of the deadeners that maximize their effect in reducing the resonance peaks of interest. After locating the deadeners in the optimum positions, it was possible to verify a strong reduction in resonance peaks of the vehicle roof, thus showing the efficiency of the procedure. The main advantage of this procedure is that it only requires FRF measurements of the vehicle in its original state not needing any previous modification of the vehicle structure to find the sensitivity functions. [DOI: 10.1115/1.4000769]
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Embedded sensitivity analysis has proven to be a useful tool in finding optimum positions of structure reinforcements. However, it was not clear how sensitivities obtained from the embedded sensitivity method were related to the normal mode, or operational mode, associated to the frequency of interest. In this work, this relationship is studied based on a finite element of a slender sheet metal piece, with preponderant bending modes. It is shown that higher sensitivities always occur at nodes or antinodes of the vibrating system. [DOI: 10.1115/1.4002127]