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PubMed1985

Dietetic staffing in Australian general hospitals.

In order to ascertain the existing and required staffing patterns of Australian dietitians, the 190 general hospitals in Australia which claim to provide an on premises dietetic service were surveyed. The questionnaire was directed to the dietitian in charge at each hospital. The 97 responses have been analysed to produce a histogram of hospital versus beds, histograms of hospitals versus required and existing dietitians, a correlation matrix for staffing predictors, regression analysis of staffing versus the predictors, a discussion of variance, and other results.

Analysis of Variance↗
PubMed2000

[Physiological mechanisms fo the formation of the adaptation- compensatory process with the impact of local vibration accompanied by noise and dust].

Based on studies and mathematic analysis of 72 parameters of body systems, the authors arranged correlation matrix and multiple regression models for 109 tunnelers and drillers. The parameters characterizing mobility of retardation and balance of nervous processes were proved to play a leading role among adaptation and compensation mechanisms of human response to local vibration, noise and dust. The authors justified criteria to reliably characterize individual sensitivity to local vibration.

Adaptation, Physiological↗
PubMed2000

[Construction of a subjective fatigue scale for adolescent students].

OBJECTIVE: There is no appropriate scale to evaluate subjective symptoms of fatigue (SSF) in everyday life in adolescent students. An existing scale long before constructed for laborers has been used. It is essential to establish a practical, rational scale. The purpose of this study was to construct a practical scale to measure subjective symptoms of fatigue for high school and college students. METHODS: A questionnaire on SSF was administered to 5,435 students aged 15-20 yr. Factor analysis based on the oblique Promax rotation method was applied to a correlation matrix consisting of 44 items. RESULTS: Six factors were interpreted as follows: difficulty with concentrated thinking, languor, reduced activation, reduced motivation, drowsiness and feeling of physical disintegration. A subjective fatigue scale (SFS-Y: 24 items) was constructed using these factors. The eigen-value of principal component analysis, alpha reliability coefficients, and test-retest reliability coefficients for each subscale were very high. CONCLUSION: The SFS-Y generated in the present study is a very practical scale with high validity and reliability.

Adolescent↗
PubMed2000

Reliability and validity of a breastfeeding attitudes instrument for nursing staff.

An instrument was designed and validated with the purpose of identifying attitudes towards breastfeeding among nursing professionals. The preliminary instrument contained 19 items which were submitted to experts in the field of human lactation and breastfeeding for content validity. The construct validity was measured through factor analysis and matrix correlation. Four factors were identified in the analysis. Overall internal consistency of the instrument was 0.83, with a subscale's range fluctuating from 0.64 to 0.73. The instrument is valid and reliable, and it is the first of its nature in Puerto Rico.

Adult↗
PubMed2001

Comparative studies on utilizing nitrogen capacity between two macroalgae Gracilaria tenuistipitata var. liui (rhodophyta) and Ulva pertusa (chlorophyta). II. Feedback controls of intracellular nitrogen pools on nitrogen uptake.

The potential feedback by intracellular nitrogen pools on maximum N uptake (NH4+) rate were determined for Gracilaria tenuistipitata var. liui and Ulva pertusa. The results of correlation matrix analyzing showed that the surge uptake of ammonium seemed related to rapid changes in small intracellular pools of inorganic nitrogen or small peptide and amino acids rather than to changes in TN content of the macroalgae. The assimilation rates of nitrogen of U. pertusa and G. tenuistipitata increased slowly during N starvation and were mainly regulated by amino acids and some incorporation of amino acids into macromolecules. From ecological point of view, the fast-growing and uptaking nutrient U. pertusa is more suitable to improve water quality in integrated shrimp culture ponds in which external nutrient supplies are usually high and constant during the culture period, while G. tenuistipitata var. liui is more suitable to be polycultured in a waters with intermittence supply of nutrients.

Amino Acids↗
PubMed2000

[Cluster analysis methods appropriate for classification of drought-resistant wheat ecotypes].

The appropriate cluster analysis methods for classification of drought-resistant wheat ecotypes were investigated, based on the analysis of 21 morphologic and agronomic characters of 15 winter wheat cultivars. According to the proximity degree to the results from experts experiences, the cluster results using original data were orderly better than those using Varimax orthogonal rotation, Promax skew intersection rotation, and principal component analysis with phenotypic mean's correlation matrix. The results using Euclidean distance were greater than those using Mahalanobis distance. The clustering methods of correspondent analysis and fuzzy cluster were better than those of nearest distance, furthest distance or group average method (UPGMA). Among all cluster results from various methods combined, the two cluster results from the fuzzy cluster using original data and from the correspondence analysis method were closest to the results of experts' experience. Based on both comparisons of results and examination of the performance of different strategies with several statistical properties, the two methods mentioned above were also acceptable.

Cluster Analysis↗
PubMedDate not supplied

[Marriage, family, and agricultural structure in Italy in the 1880s].

"This article is a contribution to the discussion on theories about household formation and marriage in Italy in the 1880s. Based on data [from] the 1881 census, it aims at verifying some hypotheses on the interdependence between marriage behaviour and socio-economic and environmental factors, by using some multivariate statistical techniques. The authors propose a number of indicators and analyse their correlation matrix, before reducing the variables to a few relevant factors which summarize a major part of the available information. Such factors are employed to determine homogeneous areas for marriage behaviour. Finally, they propose and measure some causal relationships between variables within two of the previously identified areas." (SUMMARY IN ENG AND FRE)

Agriculture↗
PubMedDate not supplied

Predictive factors in smoking cessation with combined therapy with bupropion and nicotine patches.

UNLABELLED: The association of bupropion and nicotine is a good choice in the treatment of smoking cessation. However, not all patients actually give up smoking. STUDY OBJECTIVES: This work was undertaken with the aim of finding out the functional or clinical variables that could be associated with the success of the cessation therapy. DESIGN: In one year, 88 patients who were treated with bupropion 300 mg/day and nicotine patches were followed-up, for 1 month and 3 months, respectively. They were all questioned about the number of cigarettes per day, the years they have been smoking, the number of quitting attempts, and concurrent pulmonary conditions were sought for. The Fageström Test, forced spirometry (FVC, FEV-1, FEF25-75), and exhaled carbon monoxide (by co-oxymetry) were also assessed. For the statistical analysis, a logistic regression model allowing to predict the response of new subjects to the treatment, with the lowest error possible, was applied. To choose the working model, the highest and lowest value of each variable were found, drawing the correlation matrix between dependent and independent variables, by means of the box-plot procedure. Then, the model's application conditions were analysed: linearity, homoscedasticity, independence of the applications, and normality of the distributions. To assess the discrimination of the model, a ROC curve was used. RESULTS: Showed that at the end of the follow-up year, 59.1% of the patients quitted smoking. The multivariate analysis with logistic regression showed that no previous history of chronic obstructive pulmonary disease (COPD), a FEF25-75 value and effectively quit after the first week of treatment were independent prognostic factors of treatment success. When the diagnosis precision of our model was analysed by means of the ROC curve, it showed a 78% value, with the 95% confidence interval ranging from 68.5% to 86.9%. At the optimal cut-off point of our model, sensitivity and specificity for quitting smoking were found to be 66.7% and 80%, respectively. CONCLUSIONS: We conclude that with a diagnosis precision of 78.8% patients with no history of COPD, who quitted at the first week of therapy with bupropion and with low FEF25-75, will remain non-smokers after one year follow-up. Contrarily, COPD patients who still smoke after one week of therapy, will not achieve quitting smoking.

Adult↗
PubMed2003

Waist-to-height ratio is a better obesity index than body mass index and waist-to-hip ratio for predicting diabetes, hypertension and lipidemia.

Body mass index (BMI, kg/m.sq) and waist-to-hip ratio (WHR) are widely used as obesity indices for diabetes and cardiovascular risks. Lower adult height was related to diabetes and stroke. Waist-girth was proved important for visceral obesity. Incorporating waist-girth and height as waist-to-height ratio (WHtR), we reported earlier--"Waist-to-height ratio is an important predictor of hypertension and diabetes". We readdressed this index in a larger sample with two-sample OGTT and lipid profiles. In a cluster sampling of 16,818 rural inhabitants, considering age > or = 20 y, 5713 subjects were found eligible. Of them, 4923 (M/F=2321/2602) volunteered for height, weight, blood pressure, waist-girth and hip-girth. Fasting venous blood (5 ml) was drawn for plasma glucose, total cholesterol (T-chol), Triglycerides (TG) and high-density lipoprotien (HDL-c). Overall, 1565 participants were undertaken for OGTT. The mean (SD) values of BMI, WHR and WHtR for subjects with diabetes and hypertension were significantly higher in either sex. The level significance was highest for WHtR. The prevalence of diabetes and hypertension increased significantly with higher quintiles of BMI, WHR and WHtR (chi sq values were largest in WHtR for both events). Partial correlation coefficients, controlling for age and sex, showed that BMI, WHR and WHtR significantly correlated with systolic and diastolic BP, FBG, T-chol and TG. In the entire correlation matrix, the 'r' values were the highest for WHtR. Taking diabetes and hypertension as dependent variables, logistic regression also showed the highest odds ratio in higher WHtR than BMI and WHR. We conclude that WHtR was proved again a valuable obesity index for predicting diabetes, hypertension and lipidemia.

Bangladesh↗
PubMed1992

[Classification of congenital superior oblique palsy based on principal component analysis].

An attempt was to classify unilateral congenital superior oblique palsy principal component analysis. Each principal component was calculated by taking a linear combination of an eigenvector of the correlation matrix with a standardized original variable. The variables selected for the analysis were vertical deviation in the nine diagnostic positions of 51 cases measured by a synoptometer. The cumulative contributive percent of principal components showed that 88.5% of the variation were accounted for by the first three principal components. The first principal component accounted for 56.7% of the variation in samples indicating the extent of superior oblique palsy in which vertical deviation increases or decreases proportionately. The second principal component accounted for 20.6% of the variation of samples indicating the extent of the incomitance of vertical deviation with a vertical change of gaze. The third principal component accounted for 11.1% of the variation in the sample indicating the extent of the vertical deviation with a horizontal change of gaze.

Adolescent↗
PubMed2005

Gender differences in fat patterning in children living in Ankara.

Body composition is an excellent indicator for assessing obesity and nutritional status of both individuals and populations. Youth obesity has important health and social implications, because a large proportion of adult obesity has its origin in childhood. Numerous studies report that adverse levels of cardiovascular diseases risk factors are associated with adiposity in children. Concerning the Turkish population there is up to now only limited information with regard to adiposity in children. The aim of this study was therefore to determine the anthropometric and body composition characteristics and to investigate sex differences in fat patterning including fat distribution in a group of children living in Ankara. The present study evaluated the body composition of 332 boys and 269 girls aged between 8 and 11 years, attending public schools. It was carried out by a cross-sectional study and was focused on that anthropometric variables, which reflect body fat and fat-free mass. Anthropometric measurements including height, weight, triceps and subscapular skinfolds thickness were carried out on these children. The body mass index (BMI) was also calculated. The measurements were used to estimate the two-compartment model of body composition: fat-free mass (FFM) and body fat (BF) from skinfold equations. The mean fat percentage in boys is highest at 11 years (16.8%) and lowest at 10 years (15.6%). In girls these figures come to 18.2% and 17.1%, respectively. Girls of these age groups have a significantly larger percentage of body fat and skinfold thickness. At this young age there is therefore clear evidence of sexual dimorphism in fat patterning, as girls are showing a greater subcutaneous adiposity, which is mainly contributed by the triceps fat. The body fat (kg) increases in both sexes all over the investigated age groups. The Pearson correlation matrix showed a high significant relation between the anthropometric measurements (p < 0.01). The present study confirms the findings that sexual dimorphism of fat patterning in children is to be seen in the age of 8 - 11 years. It furthermore presents basic data of body composition, which could serve as reference data in other studies on the Turkish population.

Adipose Tissue↗
PubMed2005

Serial homology and the evolution of mammalian limb covariation structure.

The tetrapod forelimb and hindlimb are serially homologous structures that share a broad range of developmental pathways responsible for their patterning and outgrowth. Covariation between limbs, which can introduce constraints on the production of variation, is related to the duplication of these developmental factors. Despite this constraint, there is remarkable diversity in limb morphology, with a variety of functional relationships between and within forelimb and hindlimb elements. Here we assess a hierarchical model of limb covariation structure based on shared developmental factors. We also test whether selection for morphologically divergent forelimbs or hindlimbs is associated with reduced covariation between limbs. Our sample includes primates, murines, a carnivoran, and a chiropteran that exhibit varying degrees of forelimb and hindlimb specialization, limb size divergence, and/or phylogenetic relatedness. We analyze the pattern and significance of between-limb morphological covariation with linear distance data collected using standard morphometric techniques and analyzed by matrix correlations, eigenanalysis, and partial correlations. Results support a common limb covariation structure across these taxa and reduced covariation between limbs in nonquadruped species. This result indicates that diversity in limb morphology has evolved without signficant modifications to a common covariation structure but that the higher degree of functional limb divergence in bats and, to some extent, gibbons is associated with weaker integration between limbs. This result supports the hypothesis that limb divergence, particularly selection for increased functional specialization, involves the reduction of developmental factors common to both limbs, thereby reducing covariation.

Animals↗
PubMed2006

Evolutionary radiation of "stone plants" in the genus Argyroderma (Aizoaceae): unraveling the effects of landscape, habitat, and flowering time.

Recent phylogenetic evidence suggests that the extraordinary diversity of the Cape Floristic Kingdom in South Africa may be the result of widespread evolutionary radiation. Our understanding of the role of adaptive versus neutral processes in these radiations remains largely speculative. In this study we investigated factors involved in the diversification of Argyroderma, a genus within the most spectacular of the Cape radiations, that of the Ruschioid subfamily of the Aizoaceae. We used amplified fragment length polymorphisms and a suite of morphological traits to elucidate patterns of differentiation within and between species of Argyroderma across the range of the genus. We then used a matrix correlation approach to assess the influence of landscape structure, edaphic gradients, and flowering phenology on phenotypic and neutral genetic divergence in the system. We found evidence for strong spatial genetic isolation at all taxonomic levels. In addition, genetic differentiation occurs along a temporal axis, between sympatric species with divergent flowering times. Morphological differentiation, which previous studies suggest is adaptive, occurs along a habitat axis, between populations occupying different edaphic microenvironments. Morphological differentiation is in turn significantly associated with flowering time shifts. Thus we propose that diversification within Argyroderma has occurred through a process of adaptive speciation in allopatry. Spatially isolated populations diverge phenotypically in response to divergent habitat selection, which in turn leads to the evolution of reproductive isolation through divergence of flowering phenologies, perhaps as a correlated response to morphological divergence. Evidence suggests that diversification of the group has proceeded in two phases: the first involving divergence of allopatric taxa on varied microhabitats within a novel habitat type (the quartz gravel plains), and the second involving range expansion of an early flowering phenotype on the most extreme edaphic habitat and subsequent incomplete differentiation of allopatric populations of the early flowering group. These results point to adaptive speciation in allopatry as a likely model for the spectacular diversification of the ice-plant family in the dissected landscapes of the southern African winter rainfall deserts.

Aizoaceae↗
PubMed2006

The stability of P in coral reef fishes.

The constancy of phenotypic variation and covariation is an assumption that underlies most recent investigations of past selective regimes and attempts to predict future responses to selection. Few studies have tested this assumption of constancy despite good reasons to expect that the pattern of phenotypic variation and covariation may vary in space and time. We compared phenotypic variance-covariance matrices (P) estimated for populations of six species of distantly related coral reef fishes sampled at two locations on Australia's Great Barrier Reef separated by more than 1000 km. The intraspecific similarity between these matrices was estimated using two methods: matrix correlation and common principal component analysis. Although there was no evidence of equality between pairs of P, both statistical approaches indicated a high degree of similarity in morphology between the two populations for each species. In general, the hierarchical decomposition of the variance-covariance structure of these populations indicated that all principal components of phenotypic variance-covariance were shared but that they differed in the degree of variation associated with each of these components. The consistency of this pattern is remarkable given the diversity of morphologies and life histories encompassed by these species. Although some phenotypic instability was indicated, these results were consistent with a generally conserved pattern of multivariate selection between populations.

Animals↗
PubMed1991

Day-time and night-time concentrations of airborne iron particles in the atmosphere of Madrid.

Specific measurements of iron aerosol have been made over a 70 days period at a semi-urban site of Madrid. Measurements were made with the idea of assessing the relative contributions of day-time and night-time concentrations to daily ones. Statistics of day-time, night-time, daily and survey time period concentrations are given. Time variations were studied as well, clearly showing daily cyclical pattern identified by applying time spectral analysis. This periodicity is undoubtedly due to level differences between day-time and night-time concentrations of aerosol. Day-time average level ranged from 0.23 to 5.13 micrograms/m3 over the entire survey period (70 days) in contrast with night-times ones ranging from 0.17 to 3.04 micrograms/m3. Night-time/day-time concentration ratio shows a highly consistent value, 0.430 + 0.25 (sigma) during this period. On occasion when diffusion conditions are similar, this ratio increases to 0.518 + 0.18 (sigma). Day-time, night-time and daily concentrations correlation matrix suggests that former is the best daily level indicator.

Aerosols↗
PubMed1991

Patellar location changes following EMG biofeedback or progressive resistive exercises.

Changes in the patellofemoral congruence (PFC) angle, the patellar rotation (PR) angle, and the sulcus angle following EMG biofeedback training that emphasized vastus medialis obliquus strengthening, the Daily Adjustable Progressive Resistive Exercise (DAPRE) technique, or no exercise were studied. Subjects were 30 normal, college females. The EMG biofeedback group and the DAPRE group followed established protocols for a 3-wk training period. The control group refrained from exercise. Patellar angles were determined with x-rays both pre- and posttest with the quadriceps relaxed and contracted. Reliability of the x-rays was determined with a correlation matrix of pre- and posttest sulcus angle measurements (P less than 0.001). EMG biofeedback training resulted in significant changes in the PFC angle with the quadriceps contracted (P less than 0.05). DAPRE resulted in significant changes in the PR angle with the quadriceps contracted (P less than 0.05). The results of this study suggest that quadriceps group strength changes are not enough to fully rehabilitate patellar tracking dysfunctions. The use of EMG biofeedback training to selectively strengthen the vastus medialis obliquus appears to be essential in correcting faulty patellar tracking.

Adult↗
PubMed1989

Construct validity of the adapted Questionnaire on Resources and Stress--short form.

The concurrent validity of the adapted version of Holroyd's (1982) short form of the Questionnaire on Resources and Stress (QRS) was examined with a sample of 103 mothers of children with mild to severe disabilities. A correlation matrix was generated using the QRS adapted short form total, its seven component factors, and six criterion measures. Results revealed significant relations among the criterion measures and their target factors as well as concurrence for the internal validity of the instrument.

Adaptation, Psychological↗