949 resultados para non-parametric technique
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Självskattad hälsa beskriver personens subjektiva uppfattning av sin hälsa. En lågt självskattad hälsa har samband med ökad framtida dödlighet. Ett starkt välbefinnande är enligt Katie Erikssons dimensioner av hälsa, förutsättningen för att hälsan ska skattas som bra. Syftet med denna studie var att beskriva eventuella skillnader i självskattad hälsa sett till olika levnadsvanor hos 40-åriga kvinnor och män. Metod: Enkätsvar från totalt 1144 40-åriga kvinnor och män har använts. Enkäterna genomfördes under 2014 på 55 vårdcentraler i två regioner i södra Sverige. Levnadsvanor som valdes till denna studie var fysisk aktivitet, grönsaks- och frukostvanor, alkoholintag, rökning, sysselsättning, sömn och stress. Självskattad hälsa kategoriserades som bra (”mycket bra” och ”bra”) och dålig (”någorlunda”, ”dålig” och ”mycket dålig”). För att studera skillnader användes Student T-test på parametrisk data och Chi-två på icke parametrisk data. Resultat: De levnadsvanor som var vanligare förekommande hos de med bra självskattad hälsa var ansträngande/hård motion, låg nivå av stress och att vara i arbete (p<.001). Att inte röka hos män och att äta frukost och grönsaker hos kvinnor var också vanligare förekommande hos de med bra självskattad hälsa. Lågt intag av alkohol visade inte på några skillnader. Slutsats: För att minska risken för framtida sjuklighet är det viktigt för distriktssköterskor, samt flera andra samhällsinsatser, att försöka påverka och uppmuntra hög fysisk aktivitet och minskad stress.
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This thesis is concerned with change point analysis for time series, i.e. with detection of structural breaks in time-ordered, random data. This long-standing research field regained popularity over the last few years and is still undergoing, as statistical analysis in general, a transformation to high-dimensional problems. We focus on the fundamental »change in the mean« problem and provide extensions of the classical non-parametric Darling-Erdős-type cumulative sum (CUSUM) testing and estimation theory within highdimensional Hilbert space settings. In the first part we contribute to (long run) principal component based testing methods for Hilbert space valued time series under a rather broad (abrupt, epidemic, gradual, multiple) change setting and under dependence. For the dependence structure we consider either traditional m-dependence assumptions or more recently developed m-approximability conditions which cover, e.g., MA, AR and ARCH models. We derive Gumbel and Brownian bridge type approximations of the distribution of the test statistic under the null hypothesis of no change and consistency conditions under the alternative. A new formulation of the test statistic using projections on subspaces allows us to simplify the standard proof techniques and to weaken common assumptions on the covariance structure. Furthermore, we propose to adjust the principal components by an implicit estimation of a (possible) change direction. This approach adds flexibility to projection based methods, weakens typical technical conditions and provides better consistency properties under the alternative. In the second part we contribute to estimation methods for common changes in the means of panels of Hilbert space valued time series. We analyze weighted CUSUM estimates within a recently proposed »high-dimensional low sample size (HDLSS)« framework, where the sample size is fixed but the number of panels increases. We derive sharp conditions on »pointwise asymptotic accuracy« or »uniform asymptotic accuracy« of those estimates in terms of the weighting function. Particularly, we prove that a covariance-based correction of Darling-Erdős-type CUSUM estimates is required to guarantee uniform asymptotic accuracy under moderate dependence conditions within panels and that these conditions are fulfilled, e.g., by any MA(1) time series. As a counterexample we show that for AR(1) time series, close to the non-stationary case, the dependence is too strong and uniform asymptotic accuracy cannot be ensured. Finally, we conduct simulations to demonstrate that our results are practically applicable and that our methodological suggestions are advantageous.
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Otoliths and scales were used to determine age and growth of: Boops boops (Linnaeus, 1758), Diplodus vulgaris (Geoffroy Saint-Hilaire, 1817), Diplodus sargus (Linnaeus, 1758), Lithognathus mormyrus (Linnaeus, 1758), Pagellus acarne (Risso, 1827), Pagellus erythrinus (Linnaeus, 1758) and Spondyliosoma cantharus (Linnaeus, 1758). These structures came from previous studies conducted in southern Portugal, and complemented by market sampling and beach seining. Von Bertalanffy growth functions were estimated with otolith and scale readings. Results indicate that otoliths are better structures for ageing these species but scales can also be used as a non-destructive technique and with satisfactory results. The exceptions were R erythrinus and S. cantharus for which scales provided better results. (c) 2007 Elsevier B.V. All rights reserved.
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Esta investigación analiza el impacto del Programa de Alimentación Escolar en el trabajo infantil en Colombia a través de varias técnicas de evaluación de impacto que incluyen emparejamiento simple, emparejamiento genético y emparejamiento con reducción de sesgo. En particular, se encuentra que este programa disminuye la probabilidad de que los escolares trabajen alrededor de un 4%. Además, se explora que el trabajo infantil se reduce gracias a que el programa aumenta la seguridad alimentaria, lo que consecuentemente cambia las decisiones de los hogares y anula la carga laboral en los infantes. Son numerosos los avances en primera infancia llevados a cabo por el Estado, sin embargo, estos resultados sirven de base para construir un marco conceptual en el que se deben rescatar y promover las políticas públicas alimentarias en toda la edad escolar.
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This study aimed at evaluating antimicrobial and antibiofilm activity of phenolic compounds present in propolis ethanol extracts (PEE). Seventy per cent ethanol extracts from seven types of propolis, one Green, two Red and four Brown collected in four Brazilian States were prepared and total phenolics, flavonoids, tannins and anthocyanins were assessed by high-performance liquid chromatography (HPLC). Minimum bactericidal concentration (MBC) and inhibitor effect on Staphylococcus aureus biofilm formation and capacity to disrupt established biofilms were assessed towards eight S. aureus isolates from milk of small ruminants with mastitis, one methicillin-resistant S. aureus (MRSA) and S. aureus ATCC 25923. To evaluate different propolis components accountability for bactericidal accomplishment and antibiofilm activity, the results were analysed by the non-parametric Spearman coefficient. Results of phenolic compounds were 216,21 to 312,08 gallic acid milligram equivalent per extract gram (mg EGA/g) of total phenolics, 55,08 to 140,6 quercetin milligram equivalent per extract gram (mg EQ/g) of flavonoids, 118,51 to 3766,16 catechin milligram equivalent per extract gram (mg EC/g) of tannins and 1,03 to 8,39 milligram per extract gram (mg/g) of anthocyanins. Red1 and Red2 showed higher tannin contents, while Red2 exhibited superior amount of anthocyanins and total phenolics. Brown3 presented higher flavonoid quantity. Green, Red1 and Red2 PEE showed the lowest levels of flavonoids, but the higher antimicrobial activity. Most PEE exhibit bactericidal activity at a concentration of 1.6 mg/mL. Brown4 PEE showed the worst capacity to inhibit S. aureus. Green PEE showed to be the most efficient in both preventing and disrupting biofilm. All PEE studied exhibited a better inhibitory activity prior-to than post-biofilm formation. According to non-parametric Spearman correlation analysis, there seems to be a significant negative correlation between the ability to disrupt biofilm and both tannins and anthocyanins contents.
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Fibromyalgia (FM) is a chronic, rheumatic disease characterized by widespread myofascial pain, of unknown aetiology, having a major impact on quality of life (QOL). Available pharmacotherapy for FM is marginally effective. FM is associated with co-morbidities of gastrointestinal (GI) disorders and Irritable Bowel Syndrome (IBS). There is growing evidence that diets low in FODMAPs, “fermentable oligo-, di- or mono-saccharides and polyols” [Low FODMAP Diet (LFD)], are effective in treating IBS. The aim of this pilot study was to examine the effects of LFDs on symptoms of FM, especially with regard to pain, QOL and GI disorders. Methods A longitudinal study using LFD intervention was performed on 38, 51 ± 10 year-old, female patients diagnosed with FM for an average of 10 years, based on ACR (American College of Rheumatology) 2010 criteria. The study was conducted from January through May, 2015, using a four-week, repeated-assessment model, as follows: Moment 0 – introduction of the protocol to participants; Moment 1 – first assessment and delivery of individual LFD dietary plans; Moment 2 – second assessment and reintroduction of FODMAPs; Moment 3 – last assessment and final nutritional counselling. Assessment tools used were the following: RFIQ (Revised Fibromyalgia Impact Questionnaire), FSQ (Fibromyalgia Survey Questionnaire), IBS-SSS (Severity Score System), EQ-5D (Euro-QOL quality of life instrument), and VAS (Visual Analogue Scale). Daily consumption of FODMAPs was quantified based on published food content analyses. Statistical analyses included ANOVA, non-parametric Friedman, t-student and Chi-square tests, using SPSS 22 software. Results The mean scores of the 38 participants at the beginning of the study were: FSQ (severity of FM, 0–31) – 22 ± 4.4; RFIQ (0–100) – 65 ± 17; IBS-SSS (0–500) – 275 ± 101; and EQ-5D (0–100) – 48 ± 19. Mean adherence to dietary regimens was 86%, confirmed by significant difference in FODMAP intakes (25 g/day vs. 2.5 g/day; p < 0.01). Comparisons between the three moments of assessment showed significant (p < 0.01) declines in scores in VAS, FSQ, and RFIQ scores, in all domains measured. An important improvement was observed with a reduction in the severity of GI symptoms, with 50% reduction in IBS scores to 138 ± 117, following LFD therapy. A significant correlation (r = 0.36; p < 0.05) was found between improvements in FM impact (declined scores) and gastrointestinal scores. There was also a significant correlation (r = 0.65; p < 0.01) between “satisfaction with improvement” after introduction of LFDs and “diet adherence”, with satisfaction of the diet achieving 77% among participants. A significant difference was observed between patients who improved as compared to those that did not improve (Chi-square χ2 = 6.16; p < .05), showing that the probability of improvement, depends on the severity of the RFIQ score. Conclusions Implementation of diet therapy involving FODMAP restrictions, in this cohort of FM patients, resulted in a significant reduction in GI disorders and FM symptoms, including pain scores. These results need to be extended in future larger studies on dietary therapy for treatment of FM. Implications According to current scientific knowledge, these are the first relevant results found in an intervention with LFD therapy in FM and must be reproduced looking for a future dietetic approach in FM.
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DEA models have been applied as the benchmarking tool in operations management to empirically account operational and productive efficiency. The wide flexibility in assigning the weights in DEA approach can result on indicators of efficiency who do not take account the relative importance of some inputs. In order to overcome this limitation, in this research we apply the DEA model under restricted weight specification. This model is applied to Spanish hotel companies in order to measure operational efficiency. The restricted weight specification enables us to decrease the influence of assigning unrealistic weights in some units and improve the efficiency estimation and to increase the discriminating potential of the conventional DEA model.
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Objectivo: Verificar os efeitos da prática da Dança Criativa (DC) em mulheres idosas, no peso (P), altura (A), índice de massa corporal (IMC), perímetro abdominal (PA), força, resistência e flexibilidade dos membros superiores e inferiores (F, R, FL-MS/MI), mobilidade física (MF) [agilidade (AG), velocidade (V), equilíbrio dinâmico (ED)], resistência aeróbia (RA) e satisfação com a vida (SV). Método: A amostra foi de 57 mulheres, entre os 65 e os 80 anos, tendo sido distribuídas aleatoriamente pelo grupo de controlo (GC) (n=25) e pelo grupo experimental (GE) (n=32). Este último frequentou aulas de DC durante 6 meses, 3 vezes por semana, com a duração de 50'. A análise estatística foi efectuada através do SPSS 17, b:mdo sido utilizadas técnicas não paramétricas. As variáveis funcionais foram avaliadas através da bateria funcional Fitness Test (Rikli & Jones, 1999) - Idosos e a SV através da Satisfaction with Live Scale (SWLS), (Diener, Larsen and Gri1fin, 1985). Resultados: Os resultados demonstraram diferenças significativas, para melhor, em todas as variáveis, excepto no P, no PA e na FLMS, entre o início e os 3 meses e entre o início E os 6 meses. No P e no PA foram observadas diferenças entre os 3 e os 15 meses. Na FRMS ambos os grupos apresentaram diferenças significativas, para melhor, e na FLMS só o GC apresentou diferenças significativas para pior. Não havia diferenças significativas entre o GE e o GC no início do estudo, excepto na RA. Conclusões: A DC promove melhorias no P; A; IMC; PA; F, R, FL-MI; MF; RA e SV em mulheres idosas. ABSTRACT: Objective: To test and verify the effects of the practice of Creative Dance in the weight, height, body mass, abdominal perimeter, strength, resistance and flexibility of the lower and upper limbs, as well as physical mobility (agility, velocity, dynamic balance), aerobic resistance and life satisfaction in elderly women. Method: 57 females constituted the sample analyzed within the ages of 65 and 80 years old randomly divided between the control group (25) and the experimental group (32). The experimental group attended 50 minutes’ classes prepared and orientated to the target core of this study during six months. The statistical analysis was processed with SPSS 17 software under non-parametric techniques. The functional battery Fitness Test (Rikli & Jones, 1999) was used to evaluate the functional variables and life satisfaction was accessed trough the Satisfaction with Live Scale (SWLS), (Diener, Larsen and Griffin, 1985). Results: The results defined positive significant differences in all variables evaluated, except weigh, abdominal perimeter and flexibility of the upper limbs between the beginning and the 3-month and the beginning and the 6- month. Differences were observed in weight and abdominal perimeter between the 3 and 6 months. 8oth groups showed considerable positive differences in the strength and resistance of the upper limbs and only the control group showed negative differences in flexibility of the upper limbs. At the beginning of the study there were no significant differences between the two groups, except in the aerobic resistance. Conclusions: Creative Dance promotes the improvement of weight, height, body mass index, abdominal perimeter, strength, resistance, flexibility of both upper and lower limbs in elderly women.
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Background: Knowing one’s own seropositivity status of HIV/AIDS is important. Seropositivity can be determined by a rapid HIV/AIDS test. Attitudes towards a rapid test of HIV/AIDS show a predisposition to perform the analysis. Objective: This study investigated, the attitudes of students and staff in a Portuguese university toward rapid HIV/AIDS test. Methods: In a convenience sample, the data was collected on campus in three consecutive years. A selfadministered structured questionnaire was used for data collection. A validated scale for Portuguese students was applied. A sample of 947 (86.3%) students and 150 (13.7%) teaching and non-teaching staff participated. The average age was 24.30 years-old (SD=8.64). Non-parametric tests were applied. Results: Attitudes of professors and non-teaching staff are more favorable in relation to the rapid test of HIV/AIDS, compared to students. Attitudes are also more favorable in the first year in which the study was conducted with both employees and students. The male students express more traditional attitudes. Students of nursing polo have expressed more favorable attitudes to the rapid test of HIV/AIDS. Conclusion: The attitudes towards rapid test of HIV/AIDS are generally favorable. It is necessary to conduct further research considering professors and other university staff. Improving favorable attitudes toward rapid HIV/AIDS test must be a positive fact for health.
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Business angels provide both financing and managerial experience, which increase the likelihood of the survival of innovative start-ups. Over the last years, European countries with developing informal venture capital markets have seen governments support the creation of business angels networks (BANs) to increase and consolidate these markets. Using the Portuguese context to carry out the empirical work, this paper provides an assessment of value added provided by angels’ networks. A total of 88 useable responses were received and analysed using non-parametric statistical techniques. This paper demonstrates that is evidence of positive contribution of BANs in terms of bringing together investors and linking them with entrepreneur’s seeking finance. BANs played an important role in financing innovative start-ups also in peripheral regions. Results lead us to conclude that government support BANs would appear to be an effective mechanism to stimulate the angel market in developing informal venture capital markets. The conclusions of this paper are likely to have relevance for countries where there is growing interest in the potential of business angels as a means of financing innovative start-ups.
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This thesis analyzes the impact of heat extremes in urban and rural environments, considering processes related to severely high temperatures and unusual dryness. The first part deals with the influence of large-scale heatwave events on the local-scale urban heat island (UHI) effect. The temperatures recorded over a 20-year summer period by meteorological stations in 37 European cities are examined to evaluate the variations of UHI during heatwaves with respect to non-heatwave days. A statistical analysis reveals a negligible impact of large-scale extreme temperatures on the local daytime urban climate, while a notable exacerbation of UHI effect at night. A comparison with the UrbClim model outputs confirms the UHI strengthening during heatwave episodes, with an intensity independent of the climate zone. The investigation of the relationship between large-scale temperature anomalies and UHI highlights a smooth and continuous dependence, but with a strong variability. The lack of a threshold behavior in this relationship suggests that large-scale temperature variability can affect the local-scale UHI even in different conditions than during extreme events. The second part examines the transition from meteorological to agricultural drought, being the first stage of the drought propagation process. A multi-year reanalysis dataset involving numerous drought events over the Iberian Peninsula is considered. The behavior of different non-parametric standardized drought indices in drought detection is evaluated. A statistical approach based on run theory is employed, analyzing the main characteristics of drought propagation. The propagation from meteorological to agricultural drought events is found to develop in about 1-2 months. The duration of agricultural drought appears shorter than that of meteorological drought, but the onset is delayed. The propagation probability increases with the severity of the originating meteorological drought. A new combined agricultural drought index is developed to be a useful tool for balancing the characteristics of other adopted indices.
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I dati delle indagini sugli apprendimenti degli studenti in Italia rivelano l’esistenza di fragilità nell’acquisizione di competenze essenziali e di differenze tra i risultati conseguiti. Per innovare la didattica al fine di adeguarla ai bisogni degli studenti, gli esperti di Docimologia caldeggiano l’uso di pratiche di valutazione formativa, o formative assessment (FA). In ambito internazionale diversi studi hanno mostrato l'efficacia di tali prassi, mentre in Italia non esistono ricerche sperimentali finalizzate a studiarne l’impatto sugli apprendimenti. Il progetto è entrato all’interno di quest’ambito di studi per controllare l’efficacia di un insieme di pratiche di FA sull'incremento delle abilità di comprensione dei testi degli studenti. Lo scopo è stato perseguito realizzando una sperimentazione in una scuola secondaria di primo grado che ha coinvolto gli studenti di due classi prime, i quali sono stati suddivisi a metà attraverso tecniche di randomizzazione per formare i due gruppi, sperimentale e di controllo. Dopo aver effettuato una rilevazione iniziale delle abilità di comprensione dei testi degli studenti (pre-test), è stato realizzato con quelli del gruppo sperimentale un intervento composto da 15 incontri di FA della durata di due ore ciascuno. Alla fine, sono state effettuate due rilevazioni finali (post-test) utilizzando sia la stessa prova utilizzata come pre-test sia una prova parallela. È stata calcolata la differenza post-test-pre-test per ogni gruppo ed è stato verificato quanto avesse influito la partecipazione all’intervento sperimentale su tale differenza tramite test non parametrici. I risultati hanno mostrato un incremento di abilità lievemente maggiore nel gruppo sperimentale, se confrontato con quello del gruppo di controllo, anche se questa differenza tra i due gruppi non è statisticamente significativa. Sebbene le analisi non abbiano consentito di rifiutare l’ipotesi nulla, la rilevanza di tale progetto risiede nel tentativo di aprire il dibattito sull’efficacia di prassi di FA sugli apprendimenti degli studenti in Italia.
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Pós-graduação em Química - IQ
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Objective To assess the prevalence of insulin resistance (IR) and associated factors in contraceptive users. Methods A total of 47 women 18 to 40 years of age with a body mass index (kg/m(2)) < 30, fasting glucose levels < 100 mg/dl and 2-hour glucose level < 140 mg/dl after a 75-g oral glucose load were submitted to a hyperinsulinemic-euglycemic clamp. The women were distributed in tertiles regarding M-values. The analysed variables were use of combined hormonal/non-hormonal contraception, duration of use, body composition, lipid profile, glucose levels and blood pressure. Results IR was detected in 19% of the participants. The women with low M-values presented significantly higher body fat mass, waist-to-hip ratio, fasting insulin, HOMA-IR and were nulligravida, showed > 1 year of contraceptive use and higher triglyceride levels. IR was more frequent among combined oral contraceptive users, however no association was observed after regression analysis. Conclusions The prevalence of IR was high among healthy women attending a family planning clinic independent of the contraceptive method used with possible long-term negative consequences regarding their metabolic and cardiovascular health. Although an association between hormonal contraception and IR could not be found this needs further research. Family planning professionals should be proactive counselling healthy women about the importance of healthy habits.
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The objective was to study the flow pattern in a plate heat exchanger (PHE) through residence time distribution (RTD) experiments. The tested PHE had flat plates and it was part of a laboratory scale pasteurization unit. Series flow and parallel flow configurations were tested with a variable number of passes and channels per pass. Owing to the small scale of the equipment and the short residence times, it was necessary to take into account the influence of the tracer detection unit on the RID data. Four theoretical RID models were adjusted: combined, series combined, generalized convection and axial dispersion. The combined model provided the best fit and it was useful to quantify the active and dead space volumes of the PHE and their dependence on its configuration. Results suggest that the axial dispersion model would present good results for a larger number of passes because of the turbulence associated with the changes of pass. This type of study can be useful to compare the hydraulic performance of different plates or to provide data for the evaluation of heat-induced changes that occur in the processing of heat-sensitive products. (C) 2011 Elsevier Ltd. All rights reserved.