845 resultados para Mann Whitney U-test
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Exercise intolerance may be reported by parents of young children with respiratory diseases. There is, however, a lack of standardized exercise protocols which allow verification of these reports especially in younger children. Consequently the aims of this pilot study were to develop a standardized treadmill walking test for children aged 4-10 years demanding low sensorimotor skills and achieving high physical exhaustion. In a prospective experimental cross sectional pilot study, 33 healthy Caucasian children were separated into three groups: G1 (4-6 years, n = 10), G2 (7-8 years, n = 12), and G3 (9-10 years, n = 11). Children performed the treadmill walking test with increasing exercise levels up to peak condition with maximal exhaustion. Gas exchange, heart rate, and lactate were measured during the test, spirometry before and after. Parameters were statistically calculated at all exercise levels as well as at 2 and 4 mmol/L lactate level for group differences (Kruskal-Wallis H-test, alpha = 0.05; post hoc: Mann-Whitney U-test with Bonferroni correction alpha = 0.05/n) and test-retest differences (Wilcoxon-rank-sum test) with SPSS. The treadmill walking test could be demonstrated to be feasible with a good repeatability within groups for most of the parameters. All children achieved a high exhaustion level. At peak level under exhaustion condition only the absolute VO2 and VCO2 differed significantly between age groups. In conclusion this newly designed treadmill walking test indicates a good feasibility, safety, and repeatability. It suggests the potential usefulness of exercise capacity monitoring for children aged from early 4 to 10 years. Various applications and test modifications will be investigated in further studies.
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BACKGROUND: The assessment of driving-relevant cognitive functions in older drivers is a difficult challenge as there is no clear-cut dividing line between normal cognition and impaired cognition and not all cognitive functions are equally important for driving. METHODS: To support decision makers, the Bern Cognitive Screening Test (BCST) for older drivers was designed. It is a computer-assisted test battery assessing visuo-spatial attention, executive functions, eye-hand coordination, distance judgment, and speed regulation. Here we compare the performance in BCST with the performance in paper and pencil cognitive screening tests and the performance in the driving simulator testing of 41 safe drivers (without crash history) and 14 unsafe drivers (with crash history). RESULTS: Safe drivers performed better than unsafe drivers in BCST (Mann-Whitney U test: U = 125.5; p = 0.001) and in the driving simulator (Student's t-test: t(44) = -2.64, p = 0.006). No clear group differences were found in paper and pencil screening tests (p > 0.05; ns). BCST was best at identifying older unsafe drivers (sensitivity 86%; specificity 61%) and was also better tolerated than the driving simulator test with fewer dropouts. CONCLUSIONS: BCST is more accurate than paper and pencil screening tests, and better tolerated than driving simulator testing when assessing driving-relevant cognition in older drivers.
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The rising problems associated with construction such as decreasing quality and productivity, labour shortages, occupational safety, and inferior working conditions have opened the possibility of more revolutionary solutions within the industry. One prospective option is in the implementation of innovative technologies such as automation and robotics, which has the potential to improve the industry in terms of productivity, safety and quality. The construction work site could, theoretically, be contained in a safer environment, with more efficient execution of the work, greater consistency of the outcome and higher level of control over the production process. By identifying the barriers to construction automation and robotics implementation in construction, and investigating ways in which to overcome them, contributions could be made in terms of better understanding and facilitating, where relevant, greater use of these technologies in the construction industry so as to promote its efficiency. This research aims to ascertain and explain the barriers to construction automation and robotics implementation by exploring and establishing the relationship between characteristics of the construction industry and attributes of existing construction automation and robotics technologies to level of usage and implementation in three selected countries; Japan, Australia and Malaysia. These three countries were chosen as their construction industry characteristics provide contrast in terms of culture, gross domestic product, technology application, organisational structure and labour policies. This research uses a mixed method approach of gathering data, both quantitative and qualitative, by employing a questionnaire survey and an interview schedule; using a wide range of sample from management through to on-site users, working in a range of small (less than AUD0.2million) to large companies (more than AUD500million), and involved in a broad range of business types and construction sectors. Detailed quantitative (statistical) and qualitative (content) data analysis is performed to provide a set of descriptions, relationships, and differences. The statistical tests selected for use include cross-tabulations, bivariate and multivariate analysis for investigating possible relationships between variables; and Kruskal-Wallis and Mann Whitney U test of independent samples for hypothesis testing and inferring the research sample to the construction industry population. Findings and conclusions arising from the research work which include the ranking schemes produced for four key areas of, the construction attributes on level of usage; barrier variables; differing levels of usage between countries; and future trends, have established a number of potential areas that could impact the level of implementation both globally and for individual countries.
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Objective: This paper explores the effects of perceived stage of cancer (PSOC) on carers' anxiety and depression during the patients' final year. Methods: A consecutive sample of patients and carers (N=98) were surveyed at regular intervals regarding PSOC, and anxiety and depression using the Hospital Anxiety and Depression Scale. Means were compared by gender using the Mann-Whitney U-test. The chi-square was used to analyse categorical data. Agreement between carers' and patients' PSOC was estimated using kappa statistics. Correlations between carers' PSOC and their anxiety and depression were calculated using the Spearman's rank correlation. Results: Over time, an increasing proportion of carers reported that the cancer was advanced, culminating at 43% near death. Agreement regarding PSOC was fair (kappa=0.29-0.34) until near death (kappa=0.21). Carers' anxiety increased over the year; depression increased in the final 6 months. Females were more anxious (p=0.049, 6 months; p=0.009, 3 months) than males, and more depressed until 1 month to death. The proportion of carers reporting moderate-severe anxiety almost doubled over the year to 27%, with more females in this category at 6 months (p=0.05). Carers with moderate-severe depression increased from 6 to 15% over the year. Increased PSOC was weakly correlated with increased anxiety and depression. Conclusions: Carers' anxiety exceeded depression in severity during advanced cancer. Females generally experienced greater anxiety and depression. Carers were more realistic than patients regarding the ultimate outcome, which was reflected in their declining mental health, particularly near the end.
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Background: Whilst the benefits of physical activity in preventing progression from impaired glucose tolerance to overt diabetes in older adults are well recognised, it is not clear which strategies may prevent progression to overt diabetes in women with recent gestational diabetes. We sought to devise and pilot test a convenient, home based exercise program with telephone support, suited to the early post partum period. Twenty eight women with recent gestational diabetes were enrolled six weeks post partum into a 12 week randomised controlled trial of Usual Care ("UC" Controls (n= 13)) vs. Supported Care ("SC" individualised exercise program with regular telephone support (n= 15)). Findings: Baseline characteristics for the whole cohort at six weeks post partum (Mean ± SD) were Age 33 ± 4 years, Weight 80 ± 20 kg and Body Mass Index (BMI) 30.0 ± 9.7 kg / m2. The primary outcome, planned physical activity, increased by Median (Range) 60 (0-540) mins/wk in the SC group vs. 0 (0-580) mins/wk in the UC group (p = 0.234, Mann Whitney U test). The change in planned physical activity predominantly comprised planned walking. Body weight, BMI, waist circumference, % body fat (measured by bioimpedance), fasting glucose and insulin did not change significantly over time in either group. Conclusions: The intervention designed to increase physical activity in post partum women with previous gestational diabetes was feasible. However, no evidence to suggest that this type of program provides any measurable improvement in metabolic or biometric parameters over a three month post partum follow up was observed.
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Purpose: To develop, using dacarbazine as a model, reliable techniques for measuring DNA damage and repair as pharmacodynamic endpoints for patients receiving chemotherapy. Methods: A group of 39 patients with malignant melanoma were treated with dacarbazine 1 g/m2 i.v. every 21 days. Tamoxifen 20 mg daily was commenced 24 h after the first infusion and continued until 3 weeks after the last cycle of chemotherapy. DNA strand breaks formed during dacarbazine-induced DNA damage and repair were measured in individual cells by the alkaline comet assay. DNA methyl adducts were quantified by measuring urinary 3-methyladenine (3-MeA) excretion using immunoaffinity ELISA. Venous blood was taken on cycles 1 and 2 for separation of peripheral blood lymphocytes (PBLs) for measurement of DNA strand breaks. Results: Wide interpatient variation in PBL DNA strand breaks occurred following chemotherapy, with a peak at 4 h (median 26.6 h, interquartile range 14.75- 40.5 h) and incomplete repair by 24 h. Similarly, there was a range of 3-MeA excretion with peak levels 4-10 h after chemotherapy (median 33 nmol/h, interquartile range 20.448.65 nmol/h). Peak 3-MeA excretion was positively correlated with DNA strand breaks at 4 h (Spearman's correlation coefficient, r = 0.39, P = 0.036) and 24 h (r = 0.46, P = 0.01). Drug-induced emesis correlated with PBL DNA strand breaks (Mann Whitney U-test, P = 0.03) but not with peak 3-MeA excretion. Conclusions: DNA damage and repair following cytotoxic chemotherapy can be measured in vivo by the alkaline comet assay and by urinary 3-MeA excretion in patients receiving chemotherapy.
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Introduction The risk for late periprosthetic fractures is higher in patients treated for a neck of femur fracture compared to those treated for osteoarthritis. It has been hypothesised that osteopenia and consequent decreased stiffness of the proximal femur are responsible for this. We investigated if a femoral component with a bigger body would increase the torque to failure in a biaxially loaded composite sawbone model. Method A biomechanical composite sawbone model was used. Two different body sizes (Exeter 44-1 vs 44-4) of a polished tapered cemented stem were implanted by an experienced surgeon, in 7 sawbones each and loaded at 40 deg/s internal rotation until failure. Torque to fracture and fracture energy were measured using a biaxial materials testing device (Instron 8874). Data are non-parametric and tested with Mann-Whitney U-test. Results The mean torque load to fracture was 154.1 NM (SD 4.4) for the 44-1 stem and 229 NM (SD10.9) for the 44-4 stem (p = 0.01). The mean fracture energy was 9.6 J (SD1.2) for the 44-1 stem and 17.2 J (SD2.0) for the 44-4 stem (p = 0.14). Conclusion the use of a large body polished tapered cemented stem for neck of femur fractures increases the torque to failure in a biomechanical model and therefore is likely to reduce late periprosthetic fracture risk in this vulnerable cohort.
Can larger-bodied cemented femoral components reduce periprosthetic fractures? A biomechanical study
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Introduction: The risk for late periprosthetic femoral fractures is higher in patients treated for a neck of femur fracture compared to osteoarthritis. It has been hypothesised that osteopenia and consequent decreased stiffness of the proximal femur are responsible for this. We investigated whether a femoral component with a bigger body would increase the torque to failure in a biaxially loaded composite Sawbone model. Material and methods: A biomechanical bone analogue was used. Two different body sizes (Exeter 44-1 vs 44-4) of a polished tapered cemented femoral stem were implanted by an experienced surgeon in 7 bone analogues each and internally rotated at 40°/s until failure. Torque to fracture and fracture energy were measured using a biaxial materials testing device (Instron 8874, MI, USA). The data were non-parametric and therefore tested with the Mann-Whitney U-test. Results: The median torque to fracture was 156.7 Nm (IQR 19.7) for the 44-1 stem and 237.1 Nm (IQR 52.9) for the 44-4 stem (p=0.001). The median fracture energy was 8.5J (IQR 7.3) for the 44-1 stem and 19.5J (IQR 8.8) for the 44-4 stem (p=0.014). Conclusions: The use of a large body polished tapered cemented stems for neck of femur fractures increases the torque to failure in a biomechanical model and therefore is likely to reduce late periprosthetic fracture risk in this vulnerable cohort.
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Interfaces for children have continued to evolve in terms of complexity, with toys ranging from traditional tangible interfaces to apps with digital interfaces and hybrid toys with mixed physical and digital interfaces. However, there is limited research done to investigate their potential for intuitive use. This research study compares a tangible toy and an equivalent toy in the digital world (app) for intuitive use. Non-parametric Mann-Whitney U test results showed that the tangible toy was more intuitive than the intangible counter part. Tangible systems are less complex to use and they require less time to encode and retrieve associated knowledge to use them intuitively. They are associated with low domain transfer distance and easily discoverable features. Intangible interfaces, on the other ha nd, require greater complexity and time to encode and retrieve associated experiential knowledge. Intangibles are associated with larger domain transfer distance and undiscoverable features which affects their intuitive use. Design implications and future work are discussed, emphasising the need for investigating aspects that make tangible systems intuitive to use.
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Population substructure and hybridization, among other factors, have the potential to cause erroneous associations in linkage disequilibrium (LD) mapping. Two closely related spotted gum eucalypts, Corymbia variegata and C. henryi (Myrtaceae) occur in sympatry in the east coast of Australia and potentially interbreed. They are morphologically similar but are distinguished as separate species based on capsule and foliage size. To determine whether they hybridize in nature and its implications for LD mapping, we investigated the level of molecular divergence between the two species at two sympatric locations separated by 300 kilometres. Very few individuals of intermediate morphology were identified, despite the two species occurring only metres apart. Analysis of genetic structure using 12 microsatellite loci showed that genetic differentiation between populations of the same species at different locations (FST = 0.07 for both species; p = 0.0001) was significantly higher than that observed between species at each location (mean FST = 0.02 and 0.04 for Cherry tree and Bunyaville respectively; p = 0.0001; all Mann-Whitney U-test p ≤ 0.01). No species-specific alleles or significant allele frequency differences were detected within a site, suggesting recurrent local gene flow between the two species. The lack of significant allele frequency differences implies no population stratification along taxonomic lines. This suggested that there is little concern for cryptic hybridization when sampling from sites of sympatry for LD mapping.
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- Background Sonography is an important diagnostic tool in children with suspected appendicitis. Reported accuracy and appendiceal visualisation rates vary significantly, as does the management of equivocal ultrasound findings. The aim of this study was to audit appendiceal sonography at a tertiary children's hospital, and provide baseline data for a future prospective study. - Summary of work Records of children who underwent ultrasound studies for possible appendicitis between January 2008 and December 2010 were reviewed. Variables included patient demographics, sonographic appendix characteristics, and secondary signs. Descriptive statistics and analysis using ANOVA, Mann-Whitney U test, and ROC curves were performed. Mater Human Research Ethic Committee approval was granted. - Summary of results There were 457 eligible children. Using a dichotomous diagnostic model (including equivocal results), sensitivity was 89.6%, specificity 91.6%, and diagnostic yield of 40.7%. ROC curve analysis of a 6mm diameter cut-off was 0.88 AUC (95% CI 0.80 to 0.95). - Discussion and conclusions Sonography is an accurate test for acute appendicitis in children, with a high sensitivity and negative predictive value. A diameter of 6mm as an absolute cut-off in a binary model can lead to false findings. Results were compared with available literature. Recent publications propose categorising diameter1 and integrating secondary signs2 to improve accuracy and provide more meaningful results to clinicians. This study will be a benchmark for future studies with multiple diagnostic categorisation.
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Intention-based models have been one of the main theoretical orientations in the research on the implementation of information and communication technology (ICT). According to these models, actual behavior can be predicted from the intention towards the behavior. If the level of intention to use technology is high, the probability of actual usage of ICT increases. The purpose of this study was to find out which factors explain vocational teachers intention to use ICT in their teaching. In addition, teachers of media and information sciences and teachers of welfare and health were compared. The study also explored how regularly ICT was applied by teachers and how strong their intention to apply the technology was. This Master s thesis is a quantitative study and the data was collected using an Email survey and Eform. The instruments were based on a decomposed theory of planned behavior. The research group consisted of 22 schools of media and information sciences and 20 schools of welfare and health. The data consisted of 231 vocational teachers: 57 teachers worked with media and information sciences and 174 with welfare and health. The data was analyzed using Mann-Whitney U-test, factor analysis and regression analysis. In addition, categorized results were compared with previous study. In this study, the intention to use ICT in teaching was explained by the teachers attitudes and skills and the attitudes of their work community. However, the environment in which ICT was used, i.e., the technical environment, economical resources and time, did not explain the intention. The results did not directly support any of the intention-based models, but they could be interpreted as congruent with the technology acceptance model. The majority of the teachers used ICT at least weekly. They had a strong intention to continue to do that in the future. The study also revealed that there were more teachers who had a critical attitude towards ICT among the teachers of welfare and health. According to the results of this study, it is not possible to state that ICT would not suit any one profession because in every group with teachers with a critical attitude towards ICT there were also teachers with a positive attitude.
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The purpose of this study was to find out whether food-related lifestyle guides and explains product evaluations, specifically, consumer perceptions and choice evaluations of five different food product categories: lettuce, mincemeat, savoury sauce, goat cheese, and pudding. The opinions of consumers who shop in neighbourhood stores were considered most valuable. This study applies means-end chain (MEC) theory, according to which products are seen as means by which consumers attain meaningful goals. The food-related lifestyle (FRL) instrument was created to study lifestyles that reflect these goals. Further, this research has adopted the view that the FRL functions as a script which guides consumer behaviour. Two research methods were used in this study. The first was the laddering interview, the primary aim of which was to gather information for formulating the questionnaire of the main study. The survey consisted of two separate questionnaires. The first was the FRL questionnaire modified for this study. The aim of the other questionnaire was to determine the choice criteria for buying five different categories of food products. Before these analyses could be made, several data modifications were made following MEC analysis procedures. Beside forming FRL dimensions by counting sum-scores from the FRL statements, factor analysis was run in order to elicit latent factors underlying the dimensions. The lifestyle factors found were adventurous, conscientious, enthusiastic, snacking, moderate, and uninvolved lifestyles. The association analyses were done separately for each choice of product as well as for each attribute-consequence linkage with a non-parametric Mann-Whitney U test. The testing variables were FRL dimensions and the FRL lifestyle factors. In addition, the relation between the attribute-consequence linkages and the demographic variables were analysed. Results from this study showed that the choice of product is sequential, so that consumers first categorize products into groups based on specific criteria like health or convenience. It was attested that the food-related lifestyles function as a script in food choice and that the FRL instrument can be used to predict consumer buying behaviour. Certain lifestyles were associated with the choice of each product category. The actual product choice within a product category then appeared to be a different matter. In addition, this study proposes a modification to the FRL instrument. The positive towards advertising FRL dimension was modified to examine many kinds of information search including the internet, TV, magazines, and other people. This new dimension, which was designated as being open to additional information, proved to be very robust and reliable in finding differences in consumer choice behaviour. Active additional information search was linked to adventurous and snacking food-related lifestyles. The results of this study support the previous knowledge that consumers expect to get many benefits simultaneously when they buy food products. This study brought detailed information about the benefits sought, the combination of benefits differing between products and between respondents. Household economy, pleasure and quality were emphasized with the choice of lettuce. Quality was the most significant benefit in choosing mincemeat, but health related benefits were often evaluated as well. The dominant benefits linked to savoury sauce were household economic benefits, expected pleasurable experiences, and a lift in self-respect. The choice of goat cheese appeared not to be an economic decision, self-respect, pleasure, and quality being included in the choice criteria. In choosing pudding, the respondents considered the well-being of family members, and indulged their family members or themselves.
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[EN] Based on an extensive theoretical review, the aim of this paper is to carry out a closer examination of the differences between exporters according to their commitment to the international market. Once the main disparities are identified by means of a non-parametric test, a logistic analysis based upon data collected from small and medium sized manufacturing firms is conducted in order to construct a classificatory model.
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O objetivo deste estudo foi avaliar o impacto do tratamento periodontal não cirúrgico sobre a atividade de elastase e o volume de fluido gengival nos pacientes portadores de periodontite crônica e agressiva generalizadas. Foram avaliados 18 pacientes com periodontite crônica (idade média 48,6 DP 7,5 anos), e 11 com periodontite agressiva (idade média 27,9 DP 6,54 anos). Foram utilizados os parâmetros clínicos de avaliação de profundidade de bolsa à sondagem (PB) (mm), nível de inserção (NI) (mm) e sangramento à sondagem (SS). As medidas clínicas e as amostras de fluido gengival foram colhidas a partir dos cinco sítios mais profundos (P) e de cinco sítios rasos com gengivite (G) de cada paciente, antes e 90 dias após o término do tratamento. As etapas clínicas obedeceram ao seguinte cronograma: seleção e exame periodontal; coleta de fluido gengival; tratamento periodontal; reavaliação, compreendendo o exame periodontal e coleta de fluido gengival. O tratamento levou, em média, 4 sessões de 40 minutos cada por paciente, com intervalo de 1 semana entre elas. As consultas para reavaliação foram feitas 90 dias após o término do tratamento. O teste de Wilcoxon foi utilizado para comparar os dados antes e depois do tratamento e o teste não pareado de Mann-Whitney U-test foi utilizado para comparar os grupos de periodontite crônica e agressiva. A amostra analisada antes e após o tratamento não apresentou diferenças significativas entre o grupo com periodontite crônica e agressiva, que responderam de forma similar a todos os indicadores avaliados, exceto para a profundidade de bolsa à sondagem nos sítios rasos com gengivite (p = 0,039) e para o sangramento à sondagem (p = 0,021) nos sítios profundos, ambos mais reduzidos na periodontite crônica após o tratamento. A elastase apresentou, após o tratamento, redução significativa nos sítios profundos, para a periodontite crônica (p = 0,012) e agressiva (p = 0,02). Em relação ao volume de fluido gengival, houve significativa redução após o tratamento nos pacientes com periodontite crônica e agressiva, tanto nos sítios rasos (p = 0,03 e p = 0,03) como nos profundos (p ˂ 0,001 e p = 0,003), respectivamente. Concluindo, os grupos com periodontite crônica e agressiva generalizadas comportaram- se de maneira semelhante frente à terapia mecânica não cirúrgica. Ainda, a terapia periodontal mecânica não cirúrgica mostrou redução significativa do volume de fluido gengival em todos os sítios analisados, e da atividade neutrofílica, nos sítios profundos, associada a reduções significativas em todos os indicadores clínicos analisados após o tratamento.