17 resultados para Non-convex optimization

em Scielo Saúde Pública - SP


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A procedure for compositional characterization of a microalgae oil is presented and applied to investigate a microalgae based biodiesel production process through process simulation. The methodology consists of: proposing a set of triacylglycerides (TAG) present in the oil; assuming an initial TAG composition and simulating the transesterification reaction (UNISIM Design, Honeywell) to obtain FAME characterization values (methyl ester composition); evaluating deviations of experimental from calculated values; minimizing the sum of squared deviations by a non-linear optimization algorithm, with TAG molar fractions as decision variables. Biodiesel from the characterized oil is compared to a rapeseed based biodiesel.

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The aim of this work was to assess the influence in the diagnostic value for human hydatid disease of the composition of bovine hydatid cyst fluid (BHCF) obtained from fertile (FC) and non-fertile cysts (NFC). Eight batches from FC and 5 from NFC were prepared and analysed with respect to chemical composition: total protein, host-derived protein, carbohydrate and lipid contents. No differences were observed in the first two parameters but carbohydrate and lipid contents were shown to be higher in batches from FC than in those from NFC. Bands of 38 and 116 kD in SDS-PAGE profiles were observed to be present in BHCF from FC only. Two pools were prepared from BHCF batches obtained from FC (PFC) and NFC (PNFC), respectively. Antigen recognition patterns were analysed by immunoblot. Physicochemical conditions for adsorption of antigens to the polystyrene surface (ELISA plates) were optimized. The diagnostic value of both types of BHCF as well as the diagnostic relevance of oxidation of their carbohydrate moieties with periodate were assessed by ELISA using 42 serum samples from hydatid patients, 41 from patients with other disorders, and 15 from healthy donors. Reactivity of all sera against native antigen were tested with and without free phosphorylcholine. The best diagnostic efficiency was observed using BHCF from periodate-treated PFC using glycine buffer with strong ionic strength to coat ELISA plates.

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Random amplified polymorphic DNA (RAPD) technique is a simple and reliable method to detect DNA polymorphism. Several factors can affect the amplification profiles, thereby causing false bands and non-reproducibility of assay. In this study, we analyzed the effect of changing the concentration of primer, magnesium chloride, template DNA and Taq DNA polymerase with the objective of determining their optimum concentration for the standardization of RAPD technique for genetic studies of Cuban Triatominae. Reproducible amplification patterns were obtained using 5 pmoL of primer, 2.5 mM of MgCl2, 25 ng of template DNA and 2 U of Taq DNA polymerase in 25 µL of the reaction. A panel of five random primers was used to evaluate the genetic variability of T. flavida. Three of these (OPA-1, OPA-2 and OPA-4) generated reproducible and distinguishable fingerprinting patterns of Triatominae. Numerical analysis of 52 RAPD amplified bands generated for all five primers was carried out with unweighted pair group method analysis (UPGMA). Jaccard's Similarity Coefficient data were used to construct a dendrogram. Two groups could be distinguished by RAPD data and these groups coincided with geographic origin, i.e. the populations captured in areas from east and west of Guanahacabibes, Pinar del Río. T. flavida present low interpopulation variability that could result in greater susceptibility to pesticides in control programs. The RAPD protocol and the selected primers are useful for molecular characterization of Cuban Triatominae.

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Ultrafast 2D NMR is a powerful methodology that allows recording of a 2D NMR spectrum in a fraction of second. However, due to the numerous non-conventional parameters involved in this methodology its implementation is no trivial task. Here, an optimized experimental protocol is carefully described to ensure efficient implementation of ultrafast NMR. The ultrafast spectra resulting from this implementation are presented based on the example of two widely used 2D NMR experiments, COSY and HSQC, obtained in 0.2 s and 41 s, respectively.

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Larvae of the genus Spodoptera spp. are highly polyphagous and can cause economical losses in several agricultural crops. Given their growing importance in the tomato crop, especially for industry, this work aimed to evaluate the feeding non-preference by larvae of Spodoptera frugiperda (J. E. Smith, 1797) and Spodoptera eridania (Cramer, 1782) on tomato genotypes and classify them by the levels of resistance. The commercial cultivar Santa Clara was set as the susceptible standard and line PI 134417 as the resistant standard to evaluate the lines PI 134418, PI 126931, LA 462 and LA 716. Feeding non-preference tests were performed under non-choice and free-choice conditions to evaluate the genotype attractiveness to larvae at predetermined times after their release, as well as the leaf area consumed. Overall, the genotypes LA 716 and PI 126931 were the least attractive to S. frugiperda, whereas Santa Clara was the most attractive and consumed. For S. eridania, the genotypes PI 126931, LA 462, LA 716 and PI 134418 were the least preferred for feeding, and Santa Clara and PI 134417 were the most attractive and consumed. The genotypes LA 716 and PI 126931 are moderately resistant to S. frugiperda and S. eridania; PI 134418 and LA 462 are moderately resistant to S. eridania; PI 134417 is susceptible to S. frugiperda and S. eridania; and Santa Clara is highly susceptible to both S. frugiperda and S. eridania.

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High mortality rates among those suffering from schizophrenia and related psychoses have been consistently described in developed societies. However, to date there is a lack of data on this matter in Brazil. In order to examine this issue, a prospective 2-year follow-up study was carried out in S. Paulo. The sample consisted of 120 consecutive admissions to psychiatric hospitals in a defined catchment area, aged 18 to 44 years old, with clinical diagnoses of non-affective functional psychoses according to the ICD-9. After 2 years, 116 (96.7%) subjects were traced. During the study period there were 7 deaths (6.0% of those traced), 5 (4.3%) due to suicide. All but one of the suicides occurred in the first year after discharge from hospital. Age and sex Standardised Mortality Ratios (relative to rates for the population of the city of Sao Paulo) were 8.4 for overall mortality (95% confidence interval: 4.0-15.9) and 317.9 for deaths due to suicide (95% confidence interval: 125.2-668.3). These results are in agreement with previous studies, and show that in Brazil non-affective functional psychoses are life-threatening illnesses, which need adequate care, particularly when patients go back to live in the community after hospital discharge.

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OBJECTIVE: The aim of the study was to identify the variables that predict the revolving door phenomenon in psychiatric hospital at the moment of a second admission. METHODS: The sample consisted of 3,093 patients who have been followed during 5 to 24 years after their first hospital admission due to schizophrenia, and affective or psychotic disorders. Those who had had four or more admissions during the study period were considered as revolving door patients. Logistic regression analyses were used to assess the impact of gender, age, marital status, urban conditions, diagnosis, mean period of stay on the first admission, interval between the first and second admissions on the patterns of hospitalization. RESULTS: The variables with the highest predictive power for readmission were the interval between first and second admissions, and the length of stay in the first admission. CONCLUSIONS: These data may help public health planners in providing optimal care to a small group of patients with more effective utilization of the available services.

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OBJECTIVE: To investigate the quality of life, life satisfaction, happiness and demands of work in workers with different work schedules. METHODS: The survey was carried out on professional workers in social care. Some were shiftworkers whose schedule included night shifts (N=311), some were shiftworkers without night shifts (N=207) and some were non-shiftworkers (N=1,210). Surveys were mailed and the response rate was 86%. For the purpose of this study several variables were selected from the Survey: The Quality of Life Profile, which measures importance, satisfaction, control and opportunities in nine domains of life plus measures of happiness, life satisfaction and demands of work. RESULTS: While both groups of shiftworkers, compared to non-shiftworkers, reported needing more physical effort to complete their work, and reported 'being' more physically tired, no differences were found in reports of overall happiness, life satisfaction or total quality of life. However, night-shiftworkers reported greater percentage of time unhappy than the other two groups of workers. In analyses of the quality of life, night-shiftworkers were less satisfied with domains of spiritual 'being' and physical and community 'belonging' than day-shiftworkers and non-shiftworkers. They also reported having fewer opportunities to improve their physical 'being', leisure, and personal growth than the other two groups. CONCLUSIONS: Quality of life in specific domains in night-shiftworkers was rated worse than in other groups of workers. Domain-based quality of life assessment gives more information regarding the particular needs of workers than overall or global measures of well-being.

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OBJECTIVE To estimate rates of non-adherence to telemedicine strategies aimed at treating drug addiction. METHODS A systematic review was conducted of randomized controlled trials investigating different telemedicine treatment methods for drug addiction. The following databases were consulted between May 18, 2012 and June 21, 2012: PubMed, PsycINFO, SciELO, Wiley (The Cochrane Library), Embase, Clinical trials and Google Scholar. The Grading of Recommendations Assessment, Development and Evaluation was used to evaluate the quality of the studies. The criteria evaluated were: appropriate sequence of data generation, allocation concealment, blinding, description of losses and exclusions and analysis by intention to treat. There were 274 studies selected, of which 20 were analyzed. RESULTS Non-adherence rates varied between 15.0% and 70.0%. The interventions evaluated were of at least three months duration and, although they all used telemedicine as support, treatment methods differed. Regarding the quality of the studies, the values also varied from very poor to high quality. High quality studies showed better adherence rates, as did those using more than one technique of intervention and a limited treatment time. Mono-user studies showed better adherence rates than poly-user studies. CONCLUSIONS Rates of non-adherence to treatment involving telemedicine on the part of users of psycho-active substances differed considerably, depending on the country, the intervention method, follow-up time and substances used. Using more than one technique of intervention, short duration of treatment and the type of substance used by patients appear to facilitate adherence.

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The treatment of relapsing chronic infections (RCI) encounters many difficulties. In the present study, the use of the immuno adjuvant P40 either alone or in association with vaccinotherapy for the treatment of RCI turned out to be very effective, whereas vaccinotherapy alone was not. It is hypothesized that cell-mediated immunity may play a major role in controlling RCI, since the clinical improvement of the patients kept up with the positivation of previously negative skin tests carried out with either the specific infecting agent or with recall-anti gens.

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Campylobacter jejuni was looked for in the feaces of 262 children, beeing 189 with acute diarrhoea, 31 with chronic diarrhoea and 42 controls. The organism was isolated from 14 (7.4%), 2 (6.5%) and 6 (14.3%) of the children, and each group, respectively.

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A retrospective survey of 473 cases of snake bite admitted to a Brazilian teaching hospital from 1984 to 1990 revealed 91 cases of bite without envenoming and/or caused by non-venomous snakes. In 17 of these cases the snake was identified, and one patient was bitten by a snake-like reptile (Amphisbaena mertensii). In 43 cases diagnosis was made on clinical grounds (fang marks in the absence of signs of envenoming). The other 30 cases were of patients who complained of being bitten but who did not show any sign of envenoming or fang mark. Most cases occurred in men (66;73%), in the 10-19 years age group (26;29%), in the lower limbs (51/74;69%), between 6 A. M. and 2 P.M. (49;61%) and in the month of April (16; 18%). One patient bitten by Philodryas olfersii developed severe local pain, swelling and redness at the site of the bite, with normal clotting time. The patient bitten by Drymarcon corais was misdiagnosed as being bitten by a snake of the genus Bothrops, was given the specific antivenom, and developed anaphylaxis. One patient bitten by Sibynomorphus mikanii presented prolonged clotting time, and was also given antivenom as a case of Bothrops bite. Correct identification of venomous snakes by physicians is necessary to provide correct treatment to victims of snake bite, avoiding unnecessary distress to the patient, and overprescription of antivenom, which may eventually cause severe untoward effects.