2,303 research outputs found

    An analysis of factors related to areawide highway traffic congestion

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    Roadway expansion is a traditional strategy used to accommodate travel demand and reduce traffic congestion in urban areas. The potential negative effects of roadway expansion and mounting concerns over urban area congestion, however, have spurred research into the factors that control congestion. The aim of this study is to investigate the relationship between traffic congestion, travel demand, and supply of roadways. To accomplish this goal, data for the top 138 urbanized areas (by population) were assembled for developing a least squares regression model. Travel Rate Index,a congestion measure developed by researchers at the Texas Transportation Institute, was selected as the response (dependent) vanable. A variety of explanatory variables were used to address highway and transit supply and travel demand related factors. The partial regression coefficients measured the effect of each explanatory (independent) variable on congestion (as measured by Travel Rate Index), holding all other independent variables constant. The results of the multiple regression analysis indicated a negative correlation between freeway lane miles and Combined Travel Rate Index. Additionally, a strong positive correlation was observed between Combined Travel Rate Index and population density and net land area, respectively. A positive correlation was observed between Combined Travel Rate Index and bus transit service revenue miles Principal arterial lane miles and rail transit revenue miles variables were not observed to be significant for explaining traffic congestion and were removed entirely during the stepwise regression The results indicated that the best predictors among the tested variables were freeway lane miles, population density, net land area, and bus revenue miles. When used together, these predictors accounted for approximately 61% of the total variation in the dependent variable, Combined Travel Rate Index. Overall, population and net land area accounted for the bulk of the variation in congestion level (Travel Rate Index)

    THE CELLULAR RECEPTOR (CD4) OF THE HUMAN IMMUNODEFICIENCY VIRUS IS EXPRESSED ON NEURONS AND GLIAL CELLS IN HUMAN BRAIN

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    The peculiar tropism of the human immunodeficiency virus (HIV) for T helper lymphocytes can be explained by a specific interaction between the virus and the CD4 molecule on these cells (1, 2). The tropism for T lymphocytes, however, can hardly account for the early brain infection observed in some AIDS (acquired immune deficiency syndrome) patients (3, 4). Since CD4 is also expressed on virus-susceptible non-T cell lines we wondered whether an additional expression site of CD4 could be demonstrated in neural tissue (5). To this end, CD4 expression in brain was analyzed with several different anti-CD4 mAbs, and using a CD4-specific cDNA probe in Northern blot analyses . CD4' cells and CD4-specific mRNA were found in the cerebellum, thalamus, and pons. The reactive cells could be identified as neurons as well as glial cells

    Züchtungsforschung für den Ökologischen Landbau an der Landessaatzuchtanstalt Hohenheim – Roggen, Triticale und Sonnenblumen

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    Breeding is an important tool to develop varieties with an optimal adaptation to organic farming. Several important traits are not covered by conventional research and breeding. At the State Plant Breeding Institute we are presently working on (1) resistance of rye to ergot (Claviceps purpurea), (2) nitrogen(N)-use efficiency in triticale, and (3) protein content of sunflower. The inheritance of these complex traits is quantitative. They are analysed in replicated field experiments at two locations in three years at several organic farms in Germany. For testing ergot resistance in rye, 68 populations, 250 full-sib families, 64 lines, and their 90 testcrosses were inoculated at mid-flowering by a spore suspension. All four material groups displayed significant (P<0.01) genotypic variation, indicating that a resistance selection should be feasible. N-use efficiency of 64 triticale genotypes was evaluated at two different N-levels. Significant genotypic variation was found, which is a prerequisite for breeding for improved N-use efficiency. To increase protein content, the 230 sunflower inbred lines investigated showed a high variation for protein and oil content. Only a small negative correlation between both traits was found. Thus, it should be possible to breed lines with high protein and high oil contents

    Reexamining the Relationship Between Shift Work and Health Behavior: Do Fluid Intelligence, Socio-economic Status, and Self-control Moderate the Relation?

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    In contemporary research, the link between shift work and health has received empirical support. Contrary to the well-established association between shift work and adverse health outcomes, literature on the link between shift work and various negative health-related behavior patterns is limited to a rather small number of studies revealing inconsistent results. This is problematic since it is assumed that shift work affects health outcomes via the effect of health behavior. Therefore, the present study aimed to investigate the relationship between shift work and select indicators of health behavior (namely, smoking, alcohol consumption, and preventive health care) as well as subjective health in a large representative German sample. In the light of inconsistent previous findings in the field, we further examined potential moderators (namely, fluid intelligence, socio-economic status, and self-control). Results are based on data from 2,590 participants. We conducted multiple regression analyses as well as mean-differences analyses. Our results suggest that shift work had no direct mean effect on health-related behavior patterns. Moreover, fluid intelligence, socio-economic status, and self-control did not moderate any effects. In accordance with the findings regarding objective health indicators, shift and day workers did not differ in the subjective perception of their health. These findings inform future research and potential interventions that should aim at fostering a healthier lifestyle not only among shift workers

    How did the beginnings of the global COVID-19 pandemic affect mental well-being?

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    The present study aims to investigate longitudinal changes in mental well-being as well as the role of individual differences in personality traits (Big Five) and the level of Personality Organisation during the first lockdown of the COVID-19 pandemic in Germany. Overall, 272 adults (Mage= 36.94, SDage= 16.46; 68.62% female, 23.45% male, 0.69% non-binary) took part in our study with four weekly surveys during the lockdown as well as a follow-up one month after restrictions were lifted. To analyse the development of mental well-being during and shortly after the first lockdown in Germany latent growth curve models (LGCM) were calculated. The considered facets of well-being differ by their trajectory. Additionally, results suggest that the lockdown did not affect all facets to the same extent. While Life Satisfaction decreases in the short term as a reaction to the lockdown, Stress and Psychological Strain were reduced after the second week of contact restrictions. When adding personality characteristics, our results showed that Neuroticism and Conscientiousness were the two dimensions associated most strongly with SWB during the first month of the pandemic. Thus, our research suggests that personality traits should be considered when analysing mental well-being

    Predictors of Refugee Adjustment: The Importance of Cognitive Skills and Personality

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    In light of the recent worldwide migration of refugees, determinants of a more or less successful integration are heavily discussed, but reliable empirical investigations are scarce and have often focused on sociodemographic factors. In the present study, we explore the role of several individual characteristics for refugee adjustment in the areas of (a) institutional, (b) interpersonal and (c) intrapersonal adaptation. In a sample of 4,527 refugees (M = 33.6 years, 38% women), we investigated the effect of sociodemographic characteristics (age, gender, months in Germany, religious affiliation), cognitive factors (cognitive ability, educational history, language skills, integration-course participation), and personality (locus of control, risk appetite, willingness to reciprocity) on adjustment parameters. Both, cognitive skills (especially language skills) and personality, showed incremental validity beyond sociodemographic factors for refugee adjustment comparable across contextual factors. Even with respect to contextual factors such as residency status and living situation, results remained largely stable. The study provides first hints on the importance of personality, thereby providing important implications for understanding integration processes and optimizing interventions on personal, social, and societal levels

    Short‐acting erythropoiesis‐stimulating agents for anaemia in predialysis patients

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    Background The benefits of erythropoiesis‐stimulating agents (ESA) for chronic kidney disease (CKD) patients have been previously demonstrated. However, the efficacy and safety of short‐acting epoetins administered at larger doses and reduced frequency as well as of new epoetins and biosimilars remains uncertain. Objectives This review aimed to evaluate the benefits and harms of different routes, frequencies and doses of epoetins (epoetin alpha, epoetin beta and other short‐acting epoetins) for anaemia in adults and children with CKD not receiving dialysis. Search methods We searched the Cochrane Kidney and Transplant Specialised Register to 12 September 2016 through contact with the Information Specialist using search terms relevant to this review. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE, and EMBASE; handsearching conference proceedings; and searching the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov. Selection criteria We included randomised control trials (RCTs) comparing different frequencies, routes, doses and types of short‐acting ESAs in CKD patients. Data collection and analysis Two authors independently assessed study eligibility and four authors assessed risk of bias and extracted data. Results were expressed as risk ratio (RR) or risk differences (RD) with 95% confidence intervals (CI) for dichotomous outcomes. For continuous outcomes the mean difference (MD) with 95% confidence intervals (CI) was used. Statistical analyses were performed using the random‐effects model. Main results We identified 14 RCTs (2616 participants); nine studies were multi‐centre and two studies involved children. The risk of bias was high in most studies; only three studies demonstrated adequate random sequence generation and only two studies were at low risk of bias for allocation concealment. Blinding of participants and personnel was at low risk of bias in one study. Blinding of outcome assessment was judged at low risk in 13 studies as the outcome measures were reported as laboratory results and therefore unlikely to be influenced by blinding. Attrition bias was at low risk of bias in eight studies while selective reporting was at low risk in six included studies. Four interventions were compared: epoetin alpha or beta at different frequencies using the same total dose (six studies); epoetin alpha at the same frequency and different total doses (two studies); epoetin alpha administered intravenously versus subcutaneous administration (one study); epoetin alpha or beta versus other epoetins or biosimilars (five studies). One study compared both different frequencies of epoetin alpha at the same total dose and at the same frequency using different total doses. Data from only 7/14 studies could be included in our meta‐analyses. There were no significant differences in final haemoglobin (Hb) levels when dosing every two weeks was compared with weekly dosing (4 studies, 785 participants: MD ‐0.20 g/dL, 95% CI ‐0.33 to ‐0.07), when four weekly dosing was compared with two weekly dosing (three studies, 671 participants: MD ‐0.16 g/dL, 95% CI ‐0.43 to 0.10) or when different total doses were administered at the same frequency (four weekly administration: one study, 144 participants: MD 0.17 g/dL 95% CI ‐0.19 to 0.53). Five studies evaluated different interventions. One study compared epoetin theta with epoetin alpha and found no significant differences in Hb levels (288 participants: MD ‐0.02 g/dL, 95% CI ‐0.25 to 0.21). One study found significantly higher pain scores with subcutaneous epoetin alpha compared with epoetin beta. Two studies (165 participants) compared epoetin delta with epoetin alpha, with no results available since the pharmaceutical company withdrew epoetin delta for commercial reasons. The fifth study comparing the biosimilar HX575 with epoetin alpha was stopped after patients receiving HX575 subcutaneously developed anti‐epoetin antibodies and no results were available. Adverse events were poorly reported in all studies and did not differ significantly within comparisons. Mortality was only detailed adequately in four studies and only one study included quality of life data. Authors' conclusions Epoetin alpha given at higher doses for extended intervals (two or four weekly) is non‐inferior to more frequent dosing intervals in maintaining final Hb levels with no significant differences in adverse effects in non‐dialysed CKD patients. However the data are of low methodological quality so that differences in efficacy and safety cannot be excluded. Further large, well designed, RCTs with patient‐centred outcomes are required to assess the safety and efficacy of large doses of the shorter acting ESAs, including biosimilars of epoetin alpha, administered less frequently compared with more frequent administration of smaller doses in children and adults with CKD not on dialysis

    Genetics, parenting, and family functioning—What drives the development of self-control from adolescence to adulthood?

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    Self-control is a meaningful predictor of crucial life outcomes. Knowingly, genes contribute substantially to differences in self-control, but behavioral genetic findings are often misinterpreted regarding environmental influences. Therefore, we reinvestigate the heritability of self-control as well as potential environmental influences, namely parenting and a chaotic home environment. We used cross-sectional and longitudinal data from the German twin family study TwinLife (N = 3354 individuals), structured in a multicohort design in which 13-, 19-, and 25-year-old twins rated their self-control, parents' behavior, and home environment. Results showed increasing mean levels and 1-year stabilities for self-control accompanied by substantial genetic influences, increasing particularly from ages 19 to 25 (53% to 76%). While chaotic home environments and negative parenting were phenotypically associated with lower self-control, twin difference models revealed that differences in these individually perceived “environments” directly predicted self-control differences (β = −0.16 to −0.28) within families when controlling for genetic and environmental similarities. In addition to the genetic anchoring of self-control, results indicate that environmental factors such as negative family environments are meaningful and depend on individual perceptions within families. Interventions for enhancing self-control should, therefore, rely on individual perspectives rather than objective characteristics of home environments

    Documentation TwinLife Data: Zygosity

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    Lenau F, Hahn E. Documentation TwinLife Data: Zygosity. TwinLife Technical Report Series. Vol 01. Bielefeld: Project TwinLife "Genetic and social causes of life chances" (Universität Bielefeld / Universität des Saarlandes); 2017
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