289 research outputs found
Modeling the unsaturated zone at the Area 5 Radioactive Waste Management Site: Effects of climate change and vegetation on flow conditions
This thesis tests a series of potential future climate scenarios and associated environmental conditions that could result in the reversal of the present upward hydraulic gradient in the vadose zone at the Area 5 Radioactive Waste Management Site (RWMS) by implementing a one-dimensional model developed using the HYDRUS 1-D numerical modeling package. The research is divided into two phases. Phase I simulates the system from the Pleistocene to Holocene transition (approximately 13,000 years ago) to the present and is tested by independently varying precipitation, evaporation and transpiration rates. The results provide initial conditions for subsequent modeling under Phase II, which considers potential future flow conditions under a series of eight possible bioclimatic scenarios analogous to potential future climates for the next +1,000 years. Results indicate that the net upward hydraulic gradient is reversed under four of the future (Phase II) cases considered where vegetation does not effectively remove available soil moisture. This scenario can occur in periods of (1) warmer temperatures, higher precipitation rates and expanded vegetation cover, (2) warmer temperatures, lower precipitation rates and reduced vegetation cover, and (3) cooler temperatures, higher precipitation rates and expanded vegetation cover
Results of precipitation monitoring at Yucca Mountain
This is the final report presenting precipitation data collected under task ORD-FYO4-007 “Precipitation Monitoring at Yucca Mountain”. This task acquired data using tipping bucket rain gauges to measure, with known accuracy, the accumulation and timing of precipitation in the vicinity of Yucca Mountain. Operation of the tipping bucket precipitation monitoring network was assumed by the Harry Reid Center for Environmental Studies (HRC) at the University of Nevada, Las Vegas (UNLV) in March of 2001. Precipitation monitoring data collection concluded June of 2008. All data presented in this report were collected during that time
Initial Plant Growth in Sand Mine Spoil Amended with Peat Moss and Fertilizer Under Greenhouse Conditions: Potential Species for Use in Reclamation
The Great Lakes Basin exhibits the largest collection of freshwater sand dunes in the world. Sand dunes are ecologically important and support a unique assemblage of flora and fauna. Sand dunes are also economically valuable. However, when sand dunes are mined, soil quality is drastically reduced. Therefore, soil quality improvements followed by revegetation maybe necessary for successful reclamation. This study evaluates the germination and initial growth of 2 legume species, sundial lupine (Lupinus perennis) and Illinois bundleflower (Desmanthus illinoensis), and 2 warm-season grass species, Indian grass (Sorghastrum nutans) and little bluestem (Schizachyrium scoparium), in the presence of 2 soil amendments (inorganic fertilizer and sphagnum peat moss) added to spoil from a local sand mine. We sowed species in pots and propagated them under greenhouse conditions. Results indicate that sundial lupine and Illinois bundleflower exhibited the greatest germination and growth among species. Peat moss had the greatest overall impact on germination and growth while the addition of fertilizer positively affected initial growth. Based on these results, sundial lupine is recognized as a primary candidate for sand mine reclamation, while Illinois bundleflower is also recommended as an appropriate species for revegetation efforts. We recommend using soil amendments that are functionally equivalent to peat in increasing soil water holding capacity. We further suggest that fertilization may be accomplished by including legumes in plant species mixes used for revegetation. Results presented here may help to identify appropriate species and soil amendments for the reclamation of former sand mines or restoration of freshwater sand dunes
Utilização de sequência didática para o aprendizado da anatomia vegetal no ensino médio
A falta de entusiasmo e materiais adequados para lecionar biologia com metodologias mais lĂşdicas e práticas Ă© perceptĂvel no ambiente escolar. Por essa razĂŁo, cientistas estĂŁo analisando práticas educativas que dinamizem e facilitem o processo de ensinoaprendizagem. A análise de livros didáticos de ensino mĂ©dio constatou que para o ensino de anatomia e histologia vegetal raramente sĂŁo disponibilizadas atividades práticas. Assim, o conteĂşdo Ă© transmitido da forma convencional, cobrando memorização de conceitos, colaborando para a falta de entusiasmo dos alunos. Com base nesse contexto, a proposta deste trabalho foi elaborar atividades didáticas para facilitar a compreensĂŁo da organização dos tecidos nos diferentes ĂłrgĂŁos vegetais e minimizar as dificuldades de interpretação dos cortes histolĂłgicos em microscĂłpios Ăłpticos de luz transmitida em campo claro. Para tanto, foi realizada uma análise qualitativa a partir de uma sequĂŞncia didática. O tema definido para essa pesquisa foi Anatomia Vegetal e as tarefas foram planejadas para a aplicação em uma turma de 1Âş ano do ensino mĂ©dio com 16 alunos, de uma escola da rede estadual de ensino pĂşblico do municĂpio de Canoas-RS. A aplicação foi realizada no Instituto Federal de Educação, CiĂŞncia e Tecnologia do Rio Grande do Sul, no centro de Porto Alegre. As maiores dificuldades nas atividades foram em relação Ă compreensĂŁo dos alunos do que era um cilindro, como realizar os planos de corte transversais e longitudinais e problemas de compreensĂŁo a respeito do que era uma cĂ©lula e um tecido. O questionário de impressões concluiu que a aula prática foi muito eficiente nos seus objetivos propostos e a maioria dos alunos respondeu que nĂŁo tiveram dificuldade em realizar o solicitado. A construção progressiva de habilidades obtidas ao longo das 3 sequĂŞncias didáticas se mostrou muito eficiente ao final de sua aplicação
"Problematiken som slår klorna i en". En kvalitativ studie om socialarbetares perspektiv på arbetet med barn till missbrukande föräldrar.
Authors: Sandra Börkell & Amanda Brandt Title: “The problem that strikes its claws into you” – A qualitative study of Social Workers’ point of view on their work with children of addicted parents. [Translated title] Supervisor: Eva Palmblad Assessor: Weddig Runquist The aim of this essay was to study, from a social worker’s point of view, their thoughts and experiences in helping children who suffer in families where drug abuse is an evident issue. With the assistance of qualitative semi-structured interviews as a choice of method we have been able to interview six social workers. The six of them were either currently working as Child protection social workers or they have in their earlier professional career. We have had our focus on four themes which has also been the foundation of the interviews: professional role, discretion, dilemma with respect to children’s perspective in order to receive the result we were looking for. The essay also contains theoretical concepts according to the professional role and discretion of the social worker. The main result shows that the social workers perceive ambivalence in their decision-making, especially towards families where the parents won’t acknowledge their addiction or when they’re refusing interventions. Another general issue has to do with the lack of time in the process of helping children who live in drug abused homes. The result also shows that the ability to create trust and an alliance with the parents and children are significant in order to make a positive change in their lives. However, the law, the organizational set of regulations, the discretion of the social worker, the parents’ consent to interventions and sometimes the parents’ denial of their addiction are what makes social work with these children complex and challenging. Keywords: drug abuse, professional role, street-level bureaucrat, discretion, child perspective Nyckelord: drogmissbruk, professionell roll, gräsrotsbyråkrat, handlingsutrymme, barnperspekti
Precipitation monitoring at Yucca Mountain
Objectives: Status of the Task to Date Network Overview/ Equipment Data Trends Uses and Collaborative Projects Spatial Interpolation of YM Rainfall Storm Event Analysis Shallow Groundwater Response to Rainfall UE29a1 Water Level Response to Barometric Pressure Fluctuatio
Precipitation Monitoring at Yucca Mountain
This work will be conducted under Task ORD-FY04-007, “Precipitation Monitoring at Yucca Mountain”. The objective of this task is to measure, with known accuracy, the accumulation and timing of precipitation around Yucca Mountain using tipping bucket rain gauges. The data are used as part of the overall work supporting the net infiltration modeling Analysis Model Report, Simulation of Net Infiltration for Modern and Potential Future Climates, and the Performance Confirmation Plan. This work is subject to UCCSN QA program requirements. This SIP presents an independent confirmatory study supporting previously gathered information
Dietary exposure biomarker-lead discovery based on Metabolomics analysis of urine samples
Although robust associations between dietary intake and population health are evident from conventional observational epidemiology, the outcomes of large-scale intervention studies testing the causality of those links have often proved inconclusive or have failed to demonstrate causality. This apparent conflict may be due to the well-recognised difficulty in measuring habitual food intake which may lead to confounding in observational epidemiology. Urine biomarkers indicative of exposure to specific foods offer information supplementary to the reliance on dietary intake self-assessment tools, such as FFQ, which are subject to individual bias. Biomarker discovery strategies using non-targeted metabolomics have been used recently to analyse urine from either short-term food intervention studies or from cohort studies in which participants consumed a freely-chosen diet. In the latter, the analysis of diet diary or FFQ information allowed classification of individuals in terms of the frequency of consumption of specific diet constituents. We review these approaches for biomarker discovery and illustrate both with particular reference to two studies carried out by the authors using approaches combining metabolite fingerprinting by MS with supervised multivariate data analysis. In both approaches, urine signals responsible for distinguishing between specific foods were identified and could be related to the chemical composition of the original foods. When using dietary data, both food distinctiveness and consumption frequency influenced whether differential dietary exposure could be discriminated adequately. We conclude that metabolomics methods for fingerprinting or profiling of overnight void urine, in particular, provide a robust strategy for dietary exposure biomarker-lead discovery.</jats:p
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