282 research outputs found
Habitat structure: a fundamental concept and framework for urban soil ecology
Habitat structure is defined as the composition and arrangement of physical matter at a location. Although habitat structure is the physical template underlying ecological patterns and processes, the concept is relatively unappreciated and underdeveloped in ecology. However, it provides a fundamental concept for urban ecology because human activities in urban ecosystems are often targeted toward management of habitat structure. In addition, the concept emphasizes the fine-scale, on-the-ground perspective needed in the study of urban soil ecology. To illustrate this, urban soil ecology research is summarized from the perspective of habitat structure effects. Among the key conclusions emerging from the literature review are: (1) habitat structure provides a unifying theme for multivariate research about urban soil ecology; (2) heterogeneous urban habitat structures influence soil ecological variables in different ways; (3) more research is needed to understand relationships among sociological variables, habitat structure patterns and urban soil ecology. To stimulate urban soil ecology research, a conceptual framework is presented to show the direct and indirect relationships among habitat structure and ecological variables. Because habitat structure serves as a physical link between sociocultural and ecological systems, it can be used as a focus for interdisciplinary and applied research (e.g., pest management) about the multiple, interactive effects of urbanization on the ecology of soils
Perspective from a Younger Generation -- The Astro-Spectroscopy of Gisbert Winnewisser
Gisbert Winnewisser's astronomical career was practically coextensive with
the whole development of molecular radio astronomy. Here I would like to pick
out a few of his many contributions, which I, personally, find particularly
interesting and put them in the context of newer results.Comment: 14 pages. (Co)authored by members of the MPIfR (Sub)millimeter
Astronomy Group. To appear in the Proceedings of the 4th
Cologne-Bonn-Zermatt-Symposium "The Dense Interstellar Medium in Galaxies"
eds. S. Pfalzner, C. Kramer, C. Straubmeier, & A. Heithausen (Springer:
Berlin
Researchers’ publication patterns and their use for author disambiguation
Over the recent years, we are witnessing an increase of the need for advanced bibliometric indicators on individual researchers and research groups, for which author disambiguation is needed. Using the complete population of university professors and researchers in the Canadian province of Québec (N=13,479), of their papers as well as the papers authored by their homonyms, this paper provides evidence of regularities in researchers’ publication patterns. It shows how these patterns can be used to automatically assign papers to individual and remove papers authored by their homonyms. Two types of patterns were found: 1) at the individual researchers’ level and 2) at the level of disciplines. On the whole, these patterns allow the construction of an algorithm that provides assignation information on at least one paper for 11,105 (82.4%) out of all 13,479 researchers—with a very low percentage of false positives (3.2%)
CD3Z Genetic Polymorphism in Immune Response to Hepatitis B Vaccination in Two Independent Chinese Populations
Vaccination against hepatitis B virus is an effective and routine practice that can prevent infection. However, vaccine-induced immunity to hepatitis B varies among individuals. CD4+ T helper cells, which play an important role in both cellular and humoral immunity, are involved in the immune response elicited by vaccination. Polymorphisms in the genes involved in stimulating the activation and proliferation of CD4+ T helper cells may influence the immune response to hepatitis B vaccination. In the first stage of the present study, a total of 111 single nucleotide polymorphisms (SNPs) in 17 genes were analyzed, using the iPLEX MassARRAY system, among 214 high responders and 107 low responders to hepatitis B vaccination. Three SNPs (rs12133337 and rs10918706 in CD3Z, rs10912564 in OX40L) were associated significantly with the immune response to hepatitis B vaccination (P = 0.008, 0.041, and 0.019, respectively). The three SNPs were analyzed further with the TaqMan-MGB or TaqMan-BHQ probe-based real-time polymerase chain reaction in another independent population, which included 1090 high responders and 636 low responders. The minor allele ‘C’ of rs12133337 continued to show an association with a lower response to hepatitis B vaccination (P = 0.033, odds radio = 1.28, 95% confidence interval = 1.01–1.61). Furthermore, in the stratified analysis for both the first and second populations, the association of the minor allele ‘C’ of rs12133337 with a lower response to hepatitis B vaccination was more prominent after individuals who were overweight or obese (body mass index ≥25 kg/m2) were excluded (1st stage: P = 0.003, 2nd stage: P = 0.002, P-combined = 9.47e-5). These findings suggest that the rs12133337 polymorphism in the CD3Z gene might affect the immune response to hepatitis B vaccination, and that a lower BMI might increase the contribution of the polymorphism to immunity to hepatitis B vaccination
Family Income Gradients in the Health and Health Care Access of US Children
This study sought to examine the shape and magnitude of family income gradients in US children’s health, access to care, and use of services. We analyzed cross-sectional data from the 2003 National Survey of Children’s Health, a telephone survey of 102,353 parents of children aged 0–17 years. Associations between family income [Below 100% Federal Poverty Level (FPL), 100–199% FPL, 200–299% FPL, 300–399% FPL, 400% FPL or Greater] and a set of 32 health and health care indicators were examined using linear polynomial testing and multivariate logistic regression. The percentage of children in better health increased with family income for 15 health outcomes. In multivariate logistic regression models that controlled for health insurance coverage and socio-demographic confounders, odds ratios >2 comparing the lowest to the highest income groups were noted for health conditions across both physical and developmental domains (diabetes, headaches, ear infections, learning disabilities, behavior/conduct problems, speech problems). Parent-reported global child health status, activity limitation, and oral health status showed steeper gradients than specific chronic and acute conditions. Ten measures of health care access and utilization were associated with family income in multivariate logistic regression models. Income gradients are pervasive across many health indicators at an early age. Social and health policy interventions are needed to address the multitude of factors that can affect children’s health and initiate disparities in development
Prediction of Psilocybin Response in Healthy Volunteers
Responses to hallucinogenic drugs, such as psilocybin, are believed to be critically dependent on the user's personality, current mood state, drug pre-experiences, expectancies, and social and environmental variables. However, little is known about the order of importance of these variables and their effect sizes in comparison to drug dose. Hence, this study investigated the effects of 24 predictor variables, including age, sex, education, personality traits, drug pre-experience, mental state before drug intake, experimental setting, and drug dose on the acute response to psilocybin. The analysis was based on the pooled data of 23 controlled experimental studies involving 409 psilocybin administrations to 261 healthy volunteers. Multiple linear mixed effects models were fitted for each of 15 response variables. Although drug dose was clearly the most important predictor for all measured response variables, several non-pharmacological variables significantly contributed to the effects of psilocybin. Specifically, having a high score in the personality trait of Absorption, being in an emotionally excitable and active state immediately before drug intake, and having experienced few psychological problems in past weeks were most strongly associated with pleasant and mystical-type experiences, whereas high Emotional Excitability, low age, and an experimental setting involving positron emission tomography most strongly predicted unpleasant and/or anxious reactions to psilocybin. The results confirm that non-pharmacological variables play an important role in the effects of psilocybin
The effects of aging of scientists on their publication and citation patterns
The average age at which U.S. researchers get their first grant from NIH has
increased from 34.3 in 1970, to 41.7 in 2004. These data raise the crucial
question of the effects of aging on the scientific creativity and productivity
of researchers. Those who worry about the aging of scientists usually believe
that the younger they are the more creative and productive they will be. Using
a large population of 13,680 university professors in Quebec, we show that,
while scientific productivity rises sharply between 28 and 40, it increases at
a slower pace between 41 and 50 and stabilizes afterward until retirement for
the most active researchers. The average scientific impact per paper decreases
linearly until 50-55 years old, but the average number of papers in highly
cited journals and among highly cited papers rises continuously until
retirement. Our results clearly show for the first time the natural history of
the scientific productivity of scientists over their entire career and bring to
light the fact that researchers over 55 still contribute significantly to the
scientific community by producing high impact papers.Comment: 12 pages, 4 figure
Policy challenges for the pediatric rheumatology workforce: Part I. Education and economics
For children with rheumatic conditions, the available pediatric rheumatology workforce mitigates their access to care. While the subspecialty experiences steady growth, a critical workforce shortage constrains access. This three-part review proposes both national and international interim policy solutions for the multiple causes of the existing unacceptable shortfall. Part I explores the impact of current educational deficits and economic obstacles which constrain appropriate access to care. Proposed policy solutions follow each identified barrier
Spectropolarimetry of stars across the H-R diagram
The growing sample of magnetic stars shows a remarkable diversity in the
properties of their magnetic fields. The overall goal of current studies is to
understand the origin, evolution, and structure of stellar magnetic fields in
stars of different mass at different evolutionary stages. In this chapter we
discuss recent measurements together with the underlying assumptions in the
interpretation of data and the requirements, both observational and
theoretical, for obtaining a realistic overview of the role of magnetic fields
in various types of stars.Comment: 23 pages, 3 figures, chapter 7 of "Astronomical Polarisation from the
Infrared to Gamma Rays", published in Astrophysics and Space Science Library
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