Evaluation of characterization techniques for beneficial use of underutilized slag materials

Wisely using byproduct materials in beneficial use applications such as highway construction is becoming more important in the United States as virgin materials are depleted and landfill capacity declines. Slags are byproducts of the steel and iron industries found in the Midwestern United States. Historically, many of these materials have historically been used in construction applications, but methods for characterizing their environmental risk are limited. This research considers a series of steps used to identify whether a particular slag poses an environmental or human health risk. The first step involves identifying the appropriate use of the material. The second step involves identifying the site-specific parameters such as precipitation rates and expected pH conditions. The third step involves characterizing the material with a set of leaching procedures that test the material under the range of expected site-specific conditions. The majority of this research focused on this characterization step. The final step involves fate and transport modeling of the appropriate leaching data to identify the ultimate constituent concentrations expected at a receptor. (Abstract shortened by UMI.)

Houseplant Poisoning in Small Animals

Plant poisoning in small animals is often overlooked as a cause of clinical problems. Even though it is an infrequent occurrence, veterinarians need to be aware of the various problem plants and their actions on the animal\u27s body. The most common body system affected is the gastrointestinal system, followed by the cardiovascular and nervous systems. Plants also cause irritation to the skin as well as mechanical injury. Some toxic substances found in plants are used to manufacture commonly used drugs. There are many examples including cardioactive glycosides, atropine, and acetylcholine. When consumed in sufficient quantities by a healthy animal even these substances can be fatal

Long-term Colloidal and Chemical Stability in Aqueous Media of NaYF₄-type Upconversion Nanoparticles Modified by Ligand-Exchange

Surface capping is an essential component of nanoparticles as it provides access to their outstanding properties in the real world. Upconversion nanoparticles are predominantly interesting for use in biological environments, due to their excellent optical properties such as the conversion of near-infrared excitation light into emissions in the visible or UV range of the spectrum, high photostability, and the absence of any intermittence. One of the most efficient upconversion nanoparticles, consisting of lanthanide doped NaYF4, suffers from limited stability in aqueous media. This study investigates a set of five types of surface coatings, ranging from small ligands to polymers of different charge and different coordinating groups, on monodisperse 28 +/- 0.9 nm sized NaYF4(Yb,Er) nanoparticles modified by a two-step ligand exchange mediated by NOBF4. Information on the long-term chemical and colloidal stability for highly diluted aqueous dispersions of these particles is acquired by transmission electron microscopy, dynamic light scattering, and luminescence spectroscopy. The findings are of importance for the development of probes and labels based on upconversion nanoparticles for biological applications

Childhood obesity and educational attainment : A systematic review

Background This report describes the findings and methods of a systematic review of research which explores the relationship between obesity and educational attainment. It has been conducted at a time of great concern about levels of obesity in the UK, and the negative physical, psychological and social impacts of obesity. Current research suggests that there may be a relationship between obesity and poor educational attainment. It is likely that obesity and poor school performance are elements of a broader picture of inequalities in health and education, whereby disadvantaged socio-economic groups tend to have poorer health and lower levels of education. However, it is possible that other factors influence obesity and attainment, such as gender, discrimination and poor mental and emotional well-being. This systematic review was therefore commissioned to address the question: What do we know about the relationship between childhood obesity and educational attainment, from the research literature? In order that our review might be informed by those closest to observing any interaction between obesity and attainment, we sought the perspectives of teachers and young people to identify the causal pathways that seemed most pertinent to them. Findings Is there a statistical association between obesity and educational attainment? While often conflicting, an overall pattern emerges from the research evidence suggesting that there is a weak negative association between obesity and educational attainment in children and young people; i.e. that higher weight is associated with lower educational attainment. Obesity is also associated with other variables, such as socio-economic status, and when these other variables are taken into consideration, the association between obesity and attainment becomes still weaker, and often loses statistical significance. To what extent does the research evidence explore the influence of the broader determinants of health, and in particular socio-economic position, in explaining any link between obesity and attainment? Place of residence, ethnicity, occupation, gender, religion, education, socio-economic status (SES) and social capital were all explored as potential moderating variables in the included research. Twenty-three of 29 studies used a measure of socio-economic status as a moderating variable. Various factors appear to contribute to low educational attainment to some extent, although given the variation in definitions, analyses and quality of data, it is impossible to point to any causative or definite risk factors. Authors of the included studies have posited theories suggesting that the link between obesity and educational attainment is moderated by individual and societal factors. Does the research evidence support or refute these? Most studies explored the influence of obesity upon attainment. Only two studies examined the influence of attainment upon obesity. Many authors suggested multiple causal pathways, many of which remained untested in their studies. The moderating variables used in statistical analyses of the relationship between obesity and attainment were not consistent with the causal pathways proposed, which is probably a reflection of the constraints imposed upon authors conducting secondary analyses of pre-existing datasets (i.e. they made use of existing variables, rather than collecting their own, tailored data). The most frequently cited factors resulting from obesity and impacting upon educational attainment were poor mental health, stigmatisation and discrimination, disordered sleep, decreased time spent in physical activity and socialising, and absenteeism. Different perspectives on obesity and attainment Few young people initially thought that obesity and educational attainment were associated. However, they considered obesity and educational attainment to be of importance to young people. Young people considered parental influence and circumstances, including family income and poverty, and bullying and emotional health to be the most important factors which might explain an association between obesity and educational attainment. Most teachers said that there was an association between obesity and educational attainment. Bullying, low self-esteem and emotional well-being, poverty and poor diet, and physical activity were commonly cited by teachers as being the most important and credible mediating variables in this association. Teachers also considered gender, ethnicity and parental influence to be important factors. While researchers, teachers and young people identified causal pathways whereby low academic attainment resulted from poor mental and emotional health among obese children and young people, only four studies adjusted for mental and emotional health variables. This may represent a significant divergence in the perspectives of researchers and stakeholders. Alternatively, it may be that in the 23 studies which conducted a secondary analysis of an existing dataset, such data were not available to the authors. Another divergence concerns the impact of reduced participation in sports and social activities. While teachers and young people located this within a broader framework of isolation and lower socialisation suffered by obese children – and thus felt reduced sports participation would result in lower attainment – three studies in the included research proposed a causal pathway in which reduced participation in sports and social activities might lead to increased time spent studying and hence higher attainment

Capturing Multivariate Spatial Dependence: Model, Estimate and then Predict

Physical processes rarely occur in isolation, rather they influence and interact with one another. Thus, there is great benefit in modeling potential dependence between both spatial locations and different processes. It is the interaction between these two dependencies that is the focus of Genton and Kleiber's paper under discussion. We see the problem of ensuring that any multivariate spatial covariance matrix is nonnegative definite as important, but we also see it as a means to an end. That "end" is solving the scientific problem of predicting a multivariate field. [arXiv:1507.08017].Comment: Published at http://dx.doi.org/10.1214/15-STS517 in the Statistical Science (http://www.imstat.org/sts/) by the Institute of Mathematical Statistics (http://www.imstat.org

Approaches to evidence synthesis in international development : a research agenda

Abstract: This paper discusses the spectrum of synthesis methods available to generate, explore and text theory, their value to the field of international development and innovations required to make better use of the primary research available. It argues for clearer distinctions between syntheses produced as public goods, and those tailored to specific circumstances; and strengthening knowledge systems through greater use of maps to navigate existing and missing evidence, harmonised outcomes and measures, and advances in automation technologies. Improved methods and guidance are required for synthesising formative research and investigating contextual factors. Engaging stakeholders and working across academic disciplines support the production of policy‐relevant syntheses and inspire methods development

Schalentragwerke mit funktionaler Gradierung

Betone für schlanke Schalentragwerke weisen zur Sicherstellung ausreichender Zugfestigkeiten oft einen hohen Stahlfasergehalt auf. Dies ist mit hohen ökologischen und monetären Kosten verbunden. Das Ziel war es daher, die Voraussetzungen für die Herstellung effizienter Schalentragwerke aus funktional fasergradierten Betonfertigteilen zu schaffen.Concrete for slender load-bearing shell structures often has a high steel fibre content to ensure sufficient tensile strength. This is associated with high ecological and financial costs. Thus, the aim of this project was to create the prerequisites for the production of efficient shell structures made of functional fibre-graded precast concrete elements