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Multiple Regression Analysis (multiple + regression_analysis)
Kinds of Multiple Regression Analysis Selected AbstractsArtificial neural networks model for the prediction of steady state phenol biodegradation in a pulsed plate bioreactorJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2008K Vidya Shetty Abstract BACKGROUND: A recent innovation in fixed film bioreactors is the pulsed plate bioreactor (PPBR) with immobilized cells. The successful development of a theoretical model for this reactor relies on the knowledge of several parameters, which may vary with the process conditions. It may also be a time-consuming and costly task because of their nonlinear nature. Artificial neural networks (ANN) offer the potential of a generic approach to the modeling of nonlinear systems. RESULTS: A feedforward ANN based model for the prediction of steady state percentage degradation of phenol in a PPBR by immobilized cells of Nocardia hydrocarbonoxydans (NCIM 2386) during continuous biodegradation has been developed to correlate the steady state percentage degradation with the flow rate, influent phenol concentration and vibrational velocity (amplitude × frequency). The model used two hidden layers and 53 parameters (weights and biases). The network model was then compared with a Multiple Regression Analysis (MRA) model, derived from the same training data. Further these two models were used to predict the percentage degradation of phenol for blind test data. CONCLUSIONS: The performance of the ANN model was superior to that of the MRA model and was found to be an efficient data-driven tool to predict the performance of a PPBR for phenol biodegradation. Copyright © 2008 Society of Chemical Industry [source] Interpersonal problems and emotional intelligence in compulsive hoardingDEPRESSION AND ANXIETY, Issue 9 2008Jessica R. Grisham Ph.D. Abstract There is some evidence that compulsive hoarding is associated with social impairment, which may contribute to poor functional outcomes among hoarding patients. In this study, individuals with compulsive hoarding (n = 30) were compared to nonhoarding anxious or depressed patients (n = 30) and nonclinical community participants (n = 30) with respect to clinical characteristics, interpersonal difficulties, and emotional intelligence. All participants were diagnosed using a semi-structured interview and completed self-report measures. Participants with compulsive hoarding endorsed more depression and schizotypal personality disorder symptoms than participants in both comparison groups. Hoarding participants also reported more interpersonal difficulties than community volunteers, but they did not differ significantly from nonhoarding participants with an anxiety or mood disorder. Multiple regression analyses demonstrated that hoarding-related beliefs were marginally related to increased interpersonal problems over and above the effect of depression and anxiety. The groups did not differ significantly with respect to emotional intelligence. Depression and Anxiety. © 2007 Wiley-Liss, Inc. [source] Subnormal energy expenditure: a putative causal factor in the weight gain induced by treatment of hyperthyroidismDIABETES OBESITY & METABOLISM, Issue 2 2006R. Jacobsen Aims:, To examine the causes of weight gain occurring as an adverse effect of treatment of hyperthyroidism. Methods:, We measured 24-h energy expenditure (EE), body composition and spontaneous physical activity (SPA) in eight patients before and 1 year after treatment of hyperthyroidism was initiated, and eight controls. Results:, One year after initiation of treatment thyrotropin was normalized, thyroid hormones had fallen to the lower end of the reference range and fat mass had increased by 3.5 kg (p < 0.001). Twenty-four hour EE adjusted for fat-free mass (FFM) was 15% higher in hyperthyroid patients before treatment than in controls (p = 0.003), and treatment decreased 24-h EE by 1.9 MJ/day (p = 0.001). After treatment, 24-h EE, adjusted for FFM, was similar to the controls. Multiple regression analyses showed that the suppressed EE could partly be attributed to an iatrogenic suppression of thyroid hormones, resulting in lower sleeping EE. Twenty-four hour SPA was normal in the hyperthyroid state, but decreased after treatment by 21% (p = 0.045), to a level not significantly different, but still below that of the controls. Conclusions:, The study suggests that weight gain during treatment of hyperthyroidism might be due to subnormal levels of EE and SPA caused by a suppression of the thyroid hormone to a level in the lower end of the normal range. [source] Patterns of co-morbidity between alcohol use and other substance use in the Australian populationDRUG AND ALCOHOL REVIEW, Issue 1 2003Dr. LOUISA DEGENHARDT Abstract The present study describes patterns of co-morbidity between alcohol use and other substance use problems in the Australian population using data from the 1997 National Survey of Mental Health and Well-Being. Multiple regression analyses examined whether the observed associations between alcohol and other drug use disorders were explained by other variables, including demographic characteristics and neuroticism. We also assessed whether the presence of co-morbid substance use disorders affected treatment seeking for a mental health problem. Alcohol use was related strongly to the use of other substances. Those who did not report alcohol use within the past 12 months were less likely to report using tobacco, cannabis, sedatives, stimulants or opiates. Higher rates again were observed among those with alcohol use disorders: half (51%) of those who were alcohol-dependent were regular tobacco smokers, one-third had used cannabis (32%); 15% reported other drug use; 15% met criteria for a cannabis use disorder and 7% met criteria for another drug use disorder. These associations were not accounted for by the demographic and other variables considered here. Co-morbid substance use disorders (sedatives, stimulants or opioids) predicted a high likelihood of seeking treatment for a mental health problem among alcohol-dependent people. [source] Reach-scale channel geometry of a mountain riverEARTH SURFACE PROCESSES AND LANDFORMS, Issue 8 2004Ellen Wohl Abstract Mountain rivers can be subject to strong constraints imposed by changes in gradient and grain size supplied by processes such as glaciation and rockfall. Nonetheless, adjustments in the channel geometry and hydraulics of mountain rivers at the reach scale can produce discernible patterns analogous to those in fully alluvial rivers. Mountain rivers can differ in that imposed reach-scale gradient is an especially important control on reach-scale channel characteristics, as indicated by examination of North St Vrain Creek in Colorado. North St Vrain Creek drains 250 km2 of the Rocky Mountains. We used 25 study reaches within the basin to examine controls on reach-scale channel geometry. Variables measured included channel geometry, large woody debris, grain size, and mean velocity. Drainage area at the study reaches ranged from 2·2 to 245 km2, and gradient from 0·013 to 0·147 m m,1. We examined correlations among (1) potential reach-scale response variables describing channel bankfull dimension and shape, hydraulics, bedform wavelength and amplitude, grain size, ,ow resistance, standard deviation of hydraulic radius, and volume of large woody debris, and (2) potential control variables that change progressively downstream (drainage area, discharge) or that are likely to re,ect a reach-speci,c control (bed gradient). We tested the hypothesis that response variables correlate most strongly with local bed gradient because of the segmented nature of mountain channels. Results from simple linear regression analyses indicate that most response variables correlate best with gradient, although channel width and width/depth ratio correlate best with discharge. Multiple regression analyses using Mallow's Cp selection criterion and log-transformation of all variables produced similar results in that most response variables correlate strongly with gradient. These results suggest that the hypothesis is partially supported: channel bed gradient is likely to be a good predictor for many reach-scale response variables along mountain rivers, but discharge is also an important predictor for some response variables. Copyright © 2004 John Wiley & Sons, Ltd. [source] Changes in alcohol consumption and beverage preference among adolescents after the introduction of the alcopops tax in GermanyADDICTION, Issue 7 2010Stefanie Müller ABSTRACT Aims The aim of this study is to assess the contribution of the alcopops tax to changes in alcohol consumption and beverage preference among adolescents in Germany. We hypothesize that the decrease of alcohol intake by alcopops is substituted by an increase of alcohol intake by other alcoholic beverages. Design Data came from the German 2003 (n = 10 551) and 2007 (n = 10 598) cross-sectional study of the European School Survey Project on Alcohol and other Drugs (ESPAD). Participants A propensity score-matched subsample of 9th and 10th graders (n = 4694) was used for the analyses. Measurement Alcohol consumption within the last 7 days was assessed by a beverage-specific quantity,frequency index. An individual's beverage preference was assigned for the beverage that had the highest share in total alcohol consumption. Multiple regression analyses were used to assess changes in alcohol consumption; changes in beverage preference were tested using multinomial logistic regression. Findings While alcopop consumption declined after the alcopops tax was implemented, consumption of spirits increased. Changes in beverage preference revealed a decrease in alcopop preference and an increase in the preference for beer and spirits. Conclusions Results indicate a partial substitution of alcopops by spirits and a switch in preference to beverages associated with riskier drinking patterns. Effective alcohol policies to prevent alcohol-related problems should focus upon the reduction of total alcohol consumption instead of regulating singular beverages. [source] Environmental factors affecting the levels of legacy pesticides in the airshed of Delaware and Chesapeake Bays, USAENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2010Anubha Goel Abstract Organochlorine insecticides and their degradation products contribute to toxicity in Chesapeake Bay, USA, sediments and affect the reproductive health of avian species in the region; however, little is known of atmospheric sources or temporal trends in concentrations of these chemicals. Weekly air (n,=,265) and daily rain samples (n,=,494) were collected over 2000 to 2003 from three locations in the Delmarva Peninsula, USA. Pesticides were consistently present in the gas phase with infrequent detection in the particle phase. Hexachlorocyclohexanes (HCHs) and cis - and trans -chlordane were detected most frequently (95,100%), and cis - and trans -nonachlor, oxychlordane, heptachlor, heptachlor epoxide, dieldrin, and 1-chloro-4-[2,2-dichloro-1-(4-chlorophenyl)ethenyl]benzene (4,4,-DDE) were also detected frequently. The highest mean air concentrations were for dieldrin (60,84,pg/m3), ,-HCH (37,83,pg/m3), and 4,4,-DDE (16,80,pg/m3). Multiple regression analyses of air concentrations with temperature and wind conditions using modified Clausius-Clapeyron equations explained only 30 to 60% of the variability in concentration for most chemicals. Comparison of the air concentrations and enthalpy of air,surface exchange values at the three sites indicate sources of chlordanes and ,-HCH sources are primarily from long-range transport. However, examination of chlordane isomer ratios indicates some local and regional contributions, and ,-HCH, 4,4,-DDE, dieldrin, heptachlor, heptachlor epoxide, and oxychlordane also have local or regional sources, possibly from contaminated soils. Median rain sample volumes of 1 to 3 L led to infrequent detections in rain; however, average measured concentrations were 2 to 10 times higher than in the Great Lakes. Dissipation half-lives in air were well below 10 years for all chemicals and below published values for the Great Lakes except dieldrin, which did not decline during the sample period. Environ. Toxicol. Chem. 2010;29:1893,1906. © 2010 SETAC [source] Gender, Delinquent Status, and Social Acceptance as Predictors of the Global Self-Esteem of TeensFAMILY & CONSUMER SCIENCES RESEARCH JOURNAL, Issue 3 2005William Scott Forney The combinations of gender, delinquent status, and social acceptance were examined as predictors of the global self-esteem of teens. Participants (N = 225) were aged 13 to 17 and included juvenile delinquents (n = 60) and high school students (n = 165) in one county in a southwest state. Factor analyses identified two dimensions of social acceptance (social verification, social interaction) and global self-esteem (self-respect, self-acceptance). Multiple regression analyses revealed the combination of gender (males) as a weak predictor and social verification as a strong predictor for self-acceptance and social interaction as a strong predictor for self-respect. Delinquent status did not predict global self-esteem. For these teens, the findings support the role of self-confirming feedback in the development of self-acceptance and the importance of socialization in forming self-respect. Implications for building self-esteem among teens are drawn for parents, high school teachers, and secondary schools. [source] Compulsive Consumption Tendencies Among Television ShoppersFAMILY & CONSUMER SCIENCES RESEARCH JOURNAL, Issue 4 2000Seung-Hee Lee Compulsive buying and binge eating are consumption behaviors that are similarly related to low self-esteem and poor impulse control, occurring more frequently in women. Using a national random sample, the authors examined the extent to which compulsive buying and binge eating were related in a nonclinical population of known television shoppers. Mailed questionnaires were completed by 334 women. Multiple regression analyses revealed that (a) binge-eating and compulsive-buying scores were positively related, and (b) both compulsive-buying and bingeeating scores were positively related to television shopping channel exposure. About 10% of the television shoppers in this study were found to have compulsive-buying tendencies. Strategies for coping with unwise compulsive consumption are offered. [source] An exploration of nutrition and eating disabilities in relation to quality of life at 6 months post-strokeHEALTH & SOCIAL CARE IN THE COMMUNITY, Issue 4 2004Lin Perry PhD MSc RGN RNT Abstract Quality of life (QoL) is increasingly recognised as an important healthcare outcome, especially for those living with enduring disability. Stroke is a major source of long-term disablement and many aspects of life after stroke have been explored. Little attention has been paid to nutritional issues despite the cultural and hedonistic importance of food and eating, and the deleterious effects of malnutrition. The present study employed an epidemiological survey to investigate the contribution of dietary and nutritional factors in relation to QoL after stroke. The participants were 206 survivors of a cohort of acute stroke patients consecutively admitted to a National Health Service trust hospital in South London, UK, between March 1998 and April 1999. They were interviewed in their homes at 6 months post-stroke. Cognitively or communication-impaired patients were precluded from interview except where a live-in carer participated as a proxy (n = 10). The participation rate for those who were eligible and could be contacted was 206 out of 218 (94%). Participants were assessed using standardised, validated tools for functional abilities in activities of daily living and eating, cognition and mood state, social support and economic indices, nutritional status, dietary intake, and QoL. Overall group scores demonstrated relatively minor degrees of physical disablement; exclusion of those with limited cognition and communication precluded assessment of a small subgroup with greater disablement at hospital discharge. Nonetheless, the overall assessment results were not dissimilar to other reported groups. Indices of poor nutritional status and substantial dietary inadequacy were revealed, linked with reduced appetite and depression. Multiple regression analyses revealed the dominant impact of mood state in relation to QoL scores; additional significant effects were identified for social support, eating-related disabilities and age. The effects of mood and social support are well-recognised, whilst nutrition-related effects have previously received little attention. Intervention in these areas might achieve improvements in survivors' perceived QoL. [source] Involvement of Helicobacter pylori Infection and Impaired Glucose Metabolism in the Increase of Brachial,Ankle Pulse Wave VelocityHELICOBACTER, Issue 5 2007Hiroyuki Yoshikawa Abstract Background: The role of Helicobacter pylori in the pathogenesis of atherosclerosis remains controversial. The present study was designed to elucidate the pathogenic role of H. pylori in the early stages of atherosclerosis by measurement of brachial,ankle pulse wave velocity (baPWV) in relation to glucose metabolism. Materials and methods: baPWV level, anti- H. pylori antibody, fasting blood glucose (FBG), and glycosylated hemoglobin A1c (HbA1c) and other conventional risk factors for cardiovascular diseases were measured in 947 subjects who attended their annual medical check-up. Results: Multiple regression analyses indicated that age, gender (male), body mass index, FBG, systolic blood pressure, and smoking habits were each independently related to baPWV values. In younger subjects (30,49 years), H. pylori seropositivity was significantly correlated with an increase of baPWV levels (r = 0.100, p = .0445). baPWV values in the H. pylori- positive subjects with impaired glucose metabolism (IG: FBG , 110 mg/dL and/or HbA1c , 5.9%) were significantly greater than those in the H. pylori- negative subjects with IG (p = .0078). Furthermore, H. pylori- positive subjects with IG were at higher risk for increase of baPWV, in younger (r = 0.203, p < .0001) as well as in older subjects (50,69 years, r = 0.099, p = .0009). Conclusions: These results suggest that H. pylori seropositivity is a potential risk factor for increased baPWV levels, and that H. pylori infection accelerates the effect of IG on an increase of baPWV, especially in younger subjects. Thus, the possible interaction between H. pylori infection and IG may contribute to the early development of atherosclerosis. [source] Pulse Pressure Determinants in Chronic Hemodialysis PatientsHEMODIALYSIS INTERNATIONAL, Issue 1 2003V Kovacic Introduction: Hypertension contributes to the cardiovascular morbidity in patients undergoing chronic hemodialysis therapy (PCHD). Pulse pressure (PP) was recognized as a correlate of mortality in PCHD. In order to demonstrate determinants of predialysis and postdialysis PP values in a group of PCHD, we conducted this study. Subjects and methods: Study subjects were 23 PCHD. Study time was 15 months. One hundred thirty six single hemodialysis (HD) treatments were processed. PP was computed as systolic-diastolic blood pressure (mmHg). Statistical methods used were Student's t test for independent data, multivariate analysis of variance, Pearson's correlation, and forward stepwise multiple regression analysis. Results: Postdialysis and predialysis PPs differed significantly (65.51 ± 19.00 vs. 60.55 ± 19.35, p = 0.002). We did not find gender differences in PP before and after HD. PP before HD was in negative correlation with phosphorus concentration (r = , 0.244, p = 0.002), parathyroid hormone (PTH)(r = , 0.177, p = 0.020), hemoglobin (r = , 0.301, p < 0.001), single HD duration (r = , 0.162, p = 0.030), ultrafiltration rate per HD (r = , 0.290, p = 0.001), years on the chronic hemodialysis treatment (r = , 0.261, p = 0.001) and ultrafiltration volume/dry body mass ratio (UF/W)(r = , 0.222, p = 0.005) and in positive concentration with weekly erythropoietin (r = 0.391, p < 001) and age (r = 0.285, p < 0.001). PP after HD was in significant negative correlation with phosphorus concentration (r = , 0.205, p = 0.009), PTH (r = , 0.187, p = 0.015), hemoglobin (r = , 0.238, p = 0.005), ultrafiltration per HD (r = , 0.370, p < 0.001), dry body mass index (r = , 0.225, p = 0.003), years of the chronic hemodialysis treatment (r = 0.330, p < 0.001), UF/W (r = , 0.340, p < 0.001) and in positive concentration with weekly erythropoietin (r = 0.361, p < 0.001) and age (r = 0.227, p = 0.004). Multiple regression analyses unveiled the strongest and negative correlations between PP after HD and UF/W ratio (, = , 0.41, p < 0.001). The strongest, but positive correlation was found between PP before HD and erythropoietin per week (, = 0.51, p < 0.001). Conclusion: Determinants of the pre/post PP values are similar. Ultrafiltration is a strong predictor of postdialysis PP value. [source] Exploring the relationship between white matter and gray matter damage in early primary progressive multiple sclerosis: An in vivo study with TBSS and VBMHUMAN BRAIN MAPPING, Issue 9 2009Benedetta Bodini Abstract We investigated the relationship between the damage occurring in the brain normal-appearing white matter (NAWM) and in the gray matter (GM) in patients with early Primary Progressive multiple sclerosis (PPMS), using Tract-Based Spatial Statistics (TBSS) and an optimized voxel-based morphometry (VBM) approach. Thirty-five patients with early PPMS underwent diffusion tensor and conventional imaging and were clinically assessed. TBSS and VBM were employed to localize regions of lower fractional anisotropy (FA) and lower GM volume in patients compared with controls. Areas of anatomical and quantitative correlation between NAWM and GM damage were detected. Multiple regression analyses were performed to investigate whether NAWM FA or GM volume of regions correlated with clinical scores independently from the other and from age and gender. In patients, we found 11 brain regions that showed an anatomical correspondence between reduced NAWM FA and GM atrophy; of these, four showed a quantitative correlation (i.e., the right sensory motor region with the adjacent corticospinal tract, the left and right thalamus with the corresponding thalamic radiations and the left insula with the adjacent WM). Either the NAWM FA or the GM volume in each of these regions correlated with disability. These results demonstrate a link between the pathological processes occurring in the NAWM and in the GM in PPMS in specific, clinically relevant brain areas. Longitudinal studies will determine whether the GM atrophy precedes or follows the NAWM damage. The methodology that we described may be useful to investigate other neurological disorders affecting both the WM and the GM. Hum Brain Mapp 2009. © 2009 Wiley-Liss, Inc. [source] The effects of early relational antecedents and other factors on the parental sensitivity of mothers and fathersINFANT AND CHILD DEVELOPMENT, Issue 1 2003Diane Pelchat Abstract This study examines the effect of early relational antecedents (ERA, i.e. the quality of parenting parents recalled receiving as children), parenting stress, marital stress, socio-economic factors and children's characteristics (gender and disability condition) on the parental sensitivity of mothers and fathers. The sample consisted of 116 mothers and 84 fathers of 117 eighteen month old children drawn from a larger longitudinal study on the adaptation of parents to a child with a disability. Thirty-four children were diagnosed with Down syndrome (DS), 51 with a cleft lip and/or palate (CLP), and 32 were non-disabled children. Multiple regression analyses reveal that mothers' sensitivity is best predicted by her level of education and family income, whereas fathers' sensitivity is best predicted by their ERA, marital stress, family income and the child's disability condition. Mothers with more education and a greater family income displayed a greater sensitivity to their children, as did fathers who perceive less marital stress, those with a greater family income and those who perceived their parents as less controlling. Also, fathers of children with DS displayed less sensitivity for their children than fathers of children with CLP or fathers of non-disabled children. These results concord with many studies about the importance of socio-economic factors, ERA, marital stress, parent's gender and children's factors in the understanding of parental sensitivity. Copyright © 2003 John Wiley & Sons, Ltd. [source] The Contribution of Foot Problems to Mobility Impairment and Falls in Community-Dwelling Older PeopleJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 12 2001Hylton B. Menz B Pod (Hons) OBJECTIVES: To investigate the relationship between foot problems, balance, and functional ability in community-dwelling older people and to determine whether older people with a history of multiple falls exhibit greater foot impairment than those who have not fallen or who have fallen once only. DESIGN: A cross-sectional, retrospective study. SETTING: Falls and Balance Laboratory, Royal North Shore Hospital, Sydney, Australia. PARTICIPANTS: One hundred thirty-five community-dwelling men and women age 75 to 93 (mean age ± standard deviation, 79.8 ± 4.1). MEASURES: Foot problem score; postural sway; coordinated stability; stair ascent and descent; an alternate stepping test; timed 6-meter walk; and tests of vision, sensation, strength, and reaction time. RESULTS: Eighty-seven percent of the sample had at least one foot problem. Women had a significantly higher foot problem score than did men. The foot problem score was significantly associated with performance on the coordinated stability test, stair ascent and descent, alternate stepping test, and timed 6-meter walk. Multiple regression analyses revealed that the foot problem score was a significant independent predictor of performance in the coordinated stability test, stair ascent and descent, and the alternate stepping test. Subjects with a history of multiple falls had a significantly higher foot problem score than did those who had not fallen or who had fallen once only, but the prevalence of individual foot conditions or the presence of foot pain did not differ between these groups. CONCLUSIONS: Foot problems are common in older people and are associated with impaired balance and performance in functional tests. Furthermore, older people with a history of multiple falls have greater foot impairment than non- or once-only fallers. These findings provide further evidence that foot problems are a falls risk factor and suggest that the cumulative effect of multiple foot problems is more important in increasing falls risk than the presence or absence of individual foot conditions. [source] The Role of Self-identity in the Theory of Planned Behavior: A Meta-AnalysisJOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 5 2010Jostein Rise The present study used meta-analysis to evaluate the role of self-identity in the theory of planned behavior (TPB). Altogether, 40 independent tests (N = 11607) could be included in the review. A large, sample-weighted average correlation between self-identity and behavioral intention was observed (r+ = .47). Multiple regression analyses showed that self-identity explained an increment of 6% of the variance in intention after controlling for the TPB components, and explained an increment of 9% of the variance when past behavior and the TPB components were controlled. The influence of self-identity on behavior was largely mediated by the strength of behavioral intentions. Theoretical implications of the findings are discussed. [source] Church Attendance and Marital Commitment Beliefs of Undergraduate WomenJOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 3 2007Siu-kuen Azor Hui Marital commitment between spouses has been found to be an important predictor of successful marriages. Beliefs about marital commitment among never-married young adults are of interest because of their probable influence on subsequent marital behaviors. The current study examined social-cognitive processes; specifically, religiousness, locus-of-control beliefs, and gender role attitudes, in the prediction of marital commitment beliefs among 294 undergraduate never-married women. We found that higher religiousness and lower chance locus of control were significantly correlated with stronger marital commitment beliefs. Multiple regression analyses revealed that religiousness was the best predictor of marital commitment beliefs in this sample. Social learning processes are implicated in the development of marital commitment beliefs. Implications and limitations of the study are discussed. [source] Ghrelin and Bone: Is There an Association in Older Adults?: The Rancho Bernardo Study,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 5 2006Lauren A Weiss Abstract Laboratory studies suggest that ghrelin is involved in bone metabolism, but studies of ghrelin and bone in humans are limited. We studied sex-specific associations of ghrelin with BMD, NTX, and bone loss. Ghrelin was not associated with BMD or bone loss in either sex. There was a significant inverse association with NTX in men but not in women. Introduction: Ghrelin is a gastric hormone recently shown to be associated with bone metabolism in animal and in vitro studies. Studies in humans are limited. We investigated the association of ghrelin with BMD, the bone resorption marker N-telopeptide (NTX), and bone loss in older men and women. Materials and Methods: Participants were 977 community-dwelling men and non,estrogen-using postmenopausal women, 50,91 years of age. Plasma ghrelin was measured by radioimmunoassay from blood obtained between 1984 and 1987. Between 1988 and 1991, BMD was measured at the midshaft radius by single photon absorptiometry and at the femoral neck, total hip, and lumbar spine by DXA. Axial BMD measurements were repeated an average of 4 years later in 544 participants. Bone turnover was assessed by NTX in urine obtained at the same time as the initial BMD. Multiple regression analyses were used to test sex-specific associations of ghrelin with BMD, NTX, and bone loss in both sexes. Results: No significant ghrelin,BMD or ghrelin,bone loss associations were observed in either sex, after adjusting for age and body mass index (BMI). Ghrelin was inversely associated with NTX in men and positively associated with NTX in women, independent of age. After adjusting for both age and BMI, this association reached statistical significance in men and was weakened in women. Conclusions: Ghrelin may be associated with bone turnover, but there is no evidence for an association with BMD or short-term change in BMD in older adults. [source] Association of Molecular Variants, Haplotypes, and Linkage Disequilibrium Within the Human Vitamin D-Binding Protein (DBP) Gene With Postmenopausal Bone Mineral Density,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 9 2003Yoichi Ezura Abstract Possible contribution of vitamin D-binding protein (DBP) gene for determination of BMD was tested by characterizing 13 SNPs in 384 adult Japanese women. When the effect of a specific single SNP was tested, five SNPs (,39C>T, IVS1+827C>T, IVS1+1916C>T, IVS1-1154A>G, and IVS11+1097G>C) correlated with BMD significantly at various levels. The chromosomal dosage of one haplotype (T-C-C-G-T-C in ,39C>T, IVS1+827C>T, IVS1+1916C>T, IVS1-1154A>G, D432E, and IVS11+1097G>C) displayed significant correlation with adjusted radial BMD (r = 0.15, p = 0.008; n = 331). Multiple regression analyses revealed a most significant correlation with the combination of IVS1+827C>T and D432E (r2 = 0.029, p = 0.005). These results indicate a complex combined effect of several SNPs within the DBP gene that might underlie susceptibility to low radial BMD and osteoporosis. Introduction: Osteoporosis results from the interplay of multiple environmental and genetic determinants. The gene encoding vitamin D-binding protein (DBP), a key factor for regulating calcium homeostasis through the vitamin D endocrine system, is a probable candidate for conferring susceptibility to osteoporosis. Methods: To test a possible contribution of the DBP gene for determination of bone mineral density (BMD) of adult women, we have characterized 13 single nucleotide polymorphisms (SNPs) within the DBP gene in DNA from 384 adult Japanese women and attempted to correlate specific SNPs with BMD. Results and Conclusions: Sixteen major haplotypes accounted for 80% of the variations, indicating allelic complexity in this genomic region. Pairwise linkage disequilibrium (LD), measured by the D, and r2 statistics, demonstrated a general pattern of decline with increasing distance, but individual LD values within small genomic segments were diverse. Regression analysis for adjusted BMD revealed significant correlation with respect to five of them (,39C>T, IVS1+827C>T, IVS1+1916C>T, IVS1-1154A>G, and IVS11+1097G>C) at various levels. An intronic SNP (IVS11+1097G>C) with the highest significance of association (p = 0.006) showed significant LD with four SNPs located around the first exon (r2 values >0.18, D, > 0.5). A non-synonymous coding SNP, D432E, showed a comparable level of correlation, but it was in a moderate LD only with IVS11+1097G>C. The chromosomal dosage of one haplotype (T-C-C-G-T-C in ,39C>T, IVS1+827C>T, IVS1+1916C>T, IVS1-1154A>G, D432E and IVS11+1097G>C) estimated in each subject displayed significant correlation with adjusted radial BMD (r = 0.15, p = 0.008; n = 331). Furthermore, multiple regression analyses revealed that the most significant correlation was achieved for the combination of IVS1+827C>T and D432E (r2 = 0.029, p = 0.005). These results indicate a complex combined effect of several SNPs within the DBP gene that might underlie susceptibility to low radial BMD and osteoporosis. [source] Symptom Perception and Adherence to Asthma Controller MedicationsJOURNAL OF NURSING SCHOLARSHIP, Issue 3 2006Ruth Ohm Purpose: To explore asthma symptom perception and the relationship between asthma symptom perception and adherence to asthma treatment. Design: Adult patients (N=120) of asthma/allergy specialty clinics, taking Advair® as a controller medication, were enrolled in this cross-sectional descriptive study. Methods: Ninety-seven participants completed 4 weeks of daily diaries to assess subjective symptom perception and measured peak expiratory flow rates (PEFR), both done twice daily. Individual perceptual accuracy scores (PAS) were determined by correlating the subjective symptom perception scores with the PEFRs. Measures included demographic variables, illness identity (personal control and treatment control, consequences, and timeline-cyclical subscales of the IPQ-R), asthma severity (FEV1 percentage) and a single-item indicator of perceived asthma severity. Adherence was measured by the Medication Adherence Report Scale (MARS) and by an Advair® dose count (percentage of doses taken as prescribed). Findings: Independent t tests comparing adherence rates of good versus poor perceivers were not significant, using either the percentage Advair® dose count or the MARS. Multiple regression analyses showed that years with asthma, illness identity, and peak flow variability were all significant explanatory variables for perceptual accuracy. Conclusion: Peak flow variability adds complexity to the relationship between perceptual accuracy and adherence that warrants further investigation. [source] Comparing the validity of multiple social effectiveness constructs in the prediction of managerial job performanceJOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 4 2006Assaf Semadar Social effectiveness constructs have been receiving increased attention in organizational research. However, the proliferation of such constructs raises questions of their relative effectiveness as predictors of job performance when used in multivariate comparison. The current study examined four social effectiveness constructs (i.e., self-monitoring, leadership self-efficacy, emotional intelligence and political skill) in the prediction of managerial job performance. Bivariate correlations showed that performance was predicted by social effectiveness constructs with the exception of self-monitoring. Multiple regression analyses, using gender and seniority as control variables, found political skill to be the strongest predictor and that it has significant incremental validity in the prediction of performance over the prediction provided by the other three social effectiveness constructs as a set. Strengths and limitations of the study are discussed, as are directions for future research. Copyright © 2006 John Wiley & Sons, Ltd. [source] Transcallosal White Matter Degradation Detected With Quantitative Fiber Tracking in Alcoholic Men and Women: Selective Relations to Dissociable FunctionsALCOHOLISM, Issue 7 2010Adolf Pfefferbaum Introduction:, Excessive alcohol consumption can adversely affect white matter fibers and disrupt transmission of neuronal signals. Here, we examined six anatomically defined transcallosal white matter fiber bundles and asked whether any bundle was specifically vulnerable to alcohol, what aspect of white matter integrity was most affected, whether women were more vulnerable than men, and whether evidence of compromise in specific bundles was associated with deficits in balance, sustained attention, associative learning, and psychomotor function, commonly affected in alcoholics. Methods:, Diffusion tensor imaging quantitative fiber tracking assessed integrity of six transcallosal white matter bundles in 87 alcoholics (59 men, 28 women) and 88 healthy controls (42 men, 46 women). Measures included orientational diffusion coherence (fractional anisotropy, FA) and magnitude of diffusion, quantified separately for axial (longitudinal; ,L) and radial (transverse; ,T) diffusivity. The Digit Symbol Test and a test of ataxia were also administered. Results:, Alcoholism negatively affected callosal FA and ,T of all but the sensory-motor bundle. Women showed no evidence for greater vulnerability to alcohol than men. Multiple regression analyses confirmed a double dissociation: higher diffusivity in sensory-motor and parietal bundles was associated with poorer balance but not psychomotor speed, whereas higher diffusivity in prefrontal and temporal bundles was associated with slower psychomotor speed but not balance. Conclusions:, This study revealed stronger alcohol effects for FA and radial diffusivity than axial diffusivity, suggesting myelin degradation, but no evidence for greater vulnerability to alcohol in women than men. The presence of brain-behavior relationships provides support for the role of alcoholism-related commissural white matter degradation as a substrate of cognitive and motor impairment. Identification of a double dissociation provides further support for the role of selective white matter integrity in specific domains of performance. [source] ANALYTICAL REGRESSION STAGE ANALYSIS FOR DEVILS HOLE, DEATH VALLEY NATIONAL PARK, NEVADA,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 4 2006M.S. Bedinger ABSTRACT: Devils Hole is a collapse depression connected to the regional carbonate aquifer of the Death Valley ground water flow system. Devils Hole pool is home to an endangered pupfish that was threatened when irrigation pumping in nearby Ash Meadows lowered the pool stage in the 1960s. Pumping at Ash Meadows ultimately ceased, and the stage recovered until 1988, when it began to decline, a trend that continued until at least 2004. Regional ground water pumping and changes in recharge are considered the principal potential stresses causing long term stage changes. A regression was found between pumpage and Devils Hole water levels. Though precipitation in distant mountain ranges is the source of recharge to the flow system, the stage of Devils Hole shows small change in stage from 1937 to 1963, a period during which ground water withdrawals were small and the major stress on stage would have been recharge. Multiple regression analyses, made by including the cumulative departure from normal precipitation with pumpage as independent variables, did not improve the regression. Drawdown at Devils Hole was calculated by the Theis Equation for nearby pumping centers to incorporate time delay and drawdown attenuation. The Theis drawdowns were used as surrogates for pumpage in multiple regression analyses. The model coefficient for the regression, R2= 0.982, indicated that changes in Devils Hole were largely due to effects of pumping at Ash Meadows, Amargosa Desert, and Army 1. [source] Ribavirin dosage in patients with HCV genotypes 2 and 3 who completed short therapy with peg-interferon ,-2b and ribavirinALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 12 2010A. MANGIA Aliment Pharmacol Ther,31, 1346,1353 Summary Background, The optimal dose of ribavirin to be used in combination with Peg-IFN in patients with HCV genotypes 2 and 3 undergoing short treatment has not been established. Aim, To explore the relationship between starting ribavirin doses, expressed as mg/kg body weight and both rapid viral response at treatment week 4 (RVR) and sustained virological response (SVR) in patients treated for 12,14 weeks with peg-interferon ,-2b and ribavirin. Methods, A post hoc analysis of data collected from two multicenter clinical trials was performed. Multiple regression analyses were employed to identify independent baseline and on-treatment predictors of RVR and SVR. For each dose of ribavirin, the empirical estimated probability of response was computed and the continuous exposure index was dichotomized by using a recursive partitioning and amalgamation method. Results, A nonlinear relationship was ascertained between ribavirin dose and RVR, but not SVR. A dose of 15.2 mg/kg was selected as the best splitting value for discriminating RVR vs. non-RVR. Regression analysis identified low baseline viraemia, genotype 2 and high ribavirin dose as independent prognostic factors for RVR. The likelihood of an SVR was not correlated with baseline ribavirin dose, but was independently predicted by adherence to the full dose throughout treatment and normal platelet counts. Conclusions, Starting high ribavirin doses appears capable of increasing the rate of RVR in patients with HCV genotypes 2 and 3 undergoing short treatment. Maintenance of the full planned dose throughout treatment is essential for achieving optimal SVR rates. [source] Health-related quality of life in a cohort of adult patients with mild hemophilia AJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 5 2008M. WALSH Summary.,Objectives:,To compare the health-related quality of life among adult males affected with mild hemophilia A due to the same mutation (Val2016ala) to that of unaffected age and sex matched controls from the same general population. Methods:,The Short-Form 36 (SF-36) and Health Assessment Questionnaire (HAQ) were used to measure health-related quality of life and physical function. Other measures included bleeding history, a measure of joint damage, body mass index, age, and viral infection status. Cross-sectional data were collected through research clinics and a retrospective chart audit over a two-year period. Results and Conclusions:,The study included 47 affected males and 33 controls. The affected males had a higher level of co-morbidity, prior bleeding, and existing joint damage than controls. With the exception of the social function and health transition scales, mean scores for each of the SF-36 domains were worse among affected males. Mean differences were more than a clinically important five points in five of eight domains, with the general health scale showing more than a 10-point difference. Despite the degree of difference noted, only two of the differences were statistically significant (general health and role emotional scales) because of the small sample size and considerable individual variation in SF-36 scale scores. Multiple regression analyses suggested existing joint damage and presence of heart disease as the strongest associates of lower physical health-related quality of life. Joint damage in turn was partly related to prior hemarthroses. Compared to the Canadian population, affected males had lower scores in six out of eight SF-36 domains as well as the physical component summary score. There were no significant differences found in the HAQ scores between the two groups. So-called mild hemophilia A was associated with a negative effect on physical health-related quality of life, contributed to by joint damage as a result of prior bleeding. [source] Psychosocial functioning and career decision-making in Israeli adolescent and young adult cancer survivors,,PEDIATRIC BLOOD & CANCER, Issue 4 2010Marilyn Stern PhD Abstract Objectives This study examined how dispositional optimism, health vulnerability, and time perspective were related to adolescent and young adult (AYA) cancer survivors' career decision-making (CDM) and quality of life (QOL). Secondarily, how cultural factors relate to CDM and QOL among Israeli-Jewish and Israeli-Arab cancer survivors was explored. Methods Fifty-one cancer survivors (68.6% females, 80.4% Israeli-Jewish, 19.6% Israeli-Arab, Mage,=,21.45 years), at least 6 months post-active treatment (Mtime,=,5.75 years) completed self-report questionnaires. Results Multiple regression analyses indicated that optimism, vulnerability, and past negative, present fatalistic, and future time perspective were significantly associated with QOL (F(6, 47),=,6.80, P,<,0.001) and CDM (F(6, 47),=,2.46, P,<,0.04). Perceived vulnerability explained the main portion of QOL variance with greater vulnerability associated with lowered QOL (,,=,0.33, P,<,0.001). Optimism was positively associated with QOL (,,=,0.55, P,<,0.02). Greater present fatalistic time perspective was associated with greater CDM difficulties (,,=,0.32, P,<,0.05). Multivariate analyses indicated greater past negative time perceptions (F(1, 46),=,8.92, P,<,0.005) and fatalism about the future (F(1, 46),=,5.90, P,<,0.02) among Israeli-Arabs as compared to Israeli-Jewish survivors. Israeli-Jewish survivors were more optimistic than Israeli-Arab survivors (F(1, 46),=,3.48, P,<,0.065). Conclusions Vulnerability, optimism, and time perspective were significantly associated with QOL and CDM among Israeli AYA cancer survivors. Israeli-Arabs viewed their pasts and futures more negatively and reported lower optimism than Israeli-Jews. Implications for future research and interventions were considered. Pediatr Blood Cancer. 2010;55:708,713. © 2010 Wiley-Liss, Inc. [source] The Family Impact of Atopic Dermatitis in Children: The Role of the Parent CaregiverPEDIATRIC DERMATOLOGY, Issue 1 2003Rajesh Balkrishnan Ph.D. We conducted a cross-sectional, exploratory analysis of how parent caregivers are affected by their child's AD, and how certain parent caregiver characteristics and perceptions affect the family impact of this condition. Parent caregivers of children with AD (n = 49) were administered a survey to collect detailed data on socioeconomic status, health perceptions, and caregiving issues. Family impact of the child's AD was measured using a modified AD Family Impact Scale. Multiple regression analyses revealed that three major factors associated with the parent caregiver were correlated with large increases in the family impact scores: 1) perception that the child's condition is severe (13%, p < 0.01), 2) high use of nonmedical services for child's condition (21%, p < 0.01), and 3) financial concern about the child's condition (18%, p < 0.01). These preliminary data indicate distinct characteristics of the parent caregiver that are associated with higher family impact of AD in children. These parent caregiver factors may be important in identifying suitable audiences and areas for education for optimal management of children's AD. [source] META-ANALYSIS OF THE RELATIONSHIP BETWEEN THE FIVE-FACTOR MODEL OF PERSONALITY AND HOLLAND'S OCCUPATIONAL TYPESPERSONNEL PSYCHOLOGY, Issue 1 2003MURRAY R. BARRICK The purpose of this study is to examine the nature and magnitude of the relationship between 2 widely accepted models for classifying individual differences,the 5-factor model of personality and Holland's RI-ASEC occupational types. Based on extensive meta-analyses, our results illustrate that there are meaningful relations between some FFM personality dimensions and some RIASEC types. The strongest relationships were obtained between the RIASEC types of enterprising and artistic with the FFM personality dimensions of Extraversion and Openness to Experience, p= .41 and .39, respectively. Three other RIASEC types had moderate correlations with at least 1 FFM personality trait. In contrast, the realistic type was not related to any FFM personality traits. Multiple regression analyses in which each RIASEC type is regressed on the FFM scores (based on meta-analytic estimates), revealed a multiple R of .11 for realistic, .26 for investigative, .42 for artistic, .31 for social, .47 for enterprising, and .27 for conventional types. The overall conclusion from the study is that although FFM personality traits and RIASEC types are related, they are not merely substitutes for each other. [source] Family migration and physical growth in Merida, Yucatan, MexicoAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2009Hugo Azcorra Merida city in Yucatan, Mexico, has received rural-to-urban migration for decades, with most immigrants settling in the city's southern neighborhoods. Exposure of immigrants to new environmental and sociocultural conditions can generate biological responses, including changes in physical growth pattern at early age. We performed a study to identify and measure the effects of family migration into south Merida on growth in 4- to 6-year-old children, measuring weight, height, sitting height, and calculated arm muscle and fat areas of 445 children: 228 natives (116 females) and 217 immigrants (118 females) and collecting family social and demographic data. Statistical analysis focused on determining differences in growth, socioeconomic, and biological variables by migratory condition and generating multiple regression models for each growth measurement. No univariate statistical differences (P > 0.05, Student's t- test) were observed in growth between studied children. Multiple regression analyses showed age, sex, mother's height, birth order, birth weight, family income, zone of residence, diet, and febrile episodes had an effect on growth. Neither the migration variable used above nor any other definition of migrant had a significant effect on growth. The lack of differences in growth between immigrant and native children is probably due to similarity in socioeconomic conditions of their families. Am. J. Hum. Biol., 2009. © 2009 Wiley-Liss, Inc. [source] A one-year survey on the use of a powder from Rosa canina lito in acute exacerbations of chronic painPHYTOTHERAPY RESEARCH, Issue 9 2008C. Chrubasik Abstract This pilot surveillance included 152 patients with acute exacerbations of chronic pain, 124 (Back group) with non-specific low back pain (NSLBP), 20 with NSLBP overridden by osteoarthritic pain (Knee-Hip group), and eight with specific LBP (included in the safety analysis). Patients were recommended the rose hip and seed powder LitozinR at a dose providing up to 3 mg of galactolipid/day for up to 54 weeks. Clinical symptoms and well-being were assessed every 6 weeks. The patients also kept a diary of their pain and the requirement for rescue medication. Data were analysed by intention to treat with last observation carried forward. Only 77 patients completed the year of surveillance. Multivariate analysis suggested an appreciable overall improvement during the surveillance, irrespective of group, and this was reflected for most of the individual measures in repeated measures ANOVA. The degree and time-course of improvement echoed that seen in similar surveillances of patients receiving an aqueous extract of Harpagophytum. Multiple regression analyses indicated that percentage changes from baseline tended to be greater in patients with greater degrees of pain and disability, but were otherwise largely unrelated to the patients' characteristics. There were no serious adverse events. The rose hip and seed powder, LitozinR, seems to deserve further, more definitive studies as a possible option in long-term management of NSLBP with or without osteoarthritic pain. Copyright © 2008 John Wiley & Sons, Ltd. 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