56 research outputs found

    Spring phytoplankton dynamics in a shallow, turbid coastal salt marsh system undergoing extreme salinity variation, South Texas

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    The contribution of phytoplankton productivity to higher trophic levels in salt marshes is not well understood. My study furthers our understanding of possible mechanisms controlling phytoplankton productivity, abundance, and community composition in salt marshes. Across three consecutive springs (2001 to 2003), I sampled the upper Nueces Delta in south Texas, a shallow, turbid, salt marsh system stressed by low freshwater inflow and wide ranging salinity (300 ppt). Water column productivity and respiration were estimated using a light-dark bottle technique, and phytoplankton biovolume and community composition were determined using inverted light microscopy. To determine their effect on the phytoplankton community, zooplankton and bacterioplankton abundance and several physical parameters were also assessed. Meaningful relationships among the numerous variables evaluated in this study were identified using principal component analysis (PCA). Despite high turbidity, phytoplankton productivity and biovolume were substantial. Resuspension appeared to play a major role in phytoplankton dynamics, as indicated by a positive relationship between ash weight and biovolume that explained up to 46% of the variation in the PCA. Negative relationships between zooplankton grazers and pennate diatoms of optimal sizes for these grazers suggested a functional grazing food chain in this system. Salinity also may have been important in phytoplankton dynamics, whereas nutrients appeared to play a minor role. Salinity increases may have been responsible for a decoupling observed between phytoplankton and grazers during late spring. Findings suggest hypotheses for future studies focused on the role of phytoplankton in salt marshes, particularly those stressed by reduced freshwater inflow and high salinities

    Value-Based Mental Health Services for Youth and Families: The Role of Patient-Reported Outcome Measures in Youth Mental Health Services

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    In Alberta, the responsibility for youth mental-health is shared among three separate government ministries, compounding the challenge of determining the value of services delivered, especially from the youth’s own perspective. As a result, Alberta’s ability to measure service quality at the systems level is limited. Yet, given the short-term and long-term effects of poor mental health on youth, families, and society, there are clinical, moral, and economic imperatives for ensuring that all services provided are of the highest value possible.  Currently, Alberta is limited to estimating value mainly through quantitative measures focused on the cost of service delivery. However, value-based health-care services are measured as quality or outcomes for persons receiving health services in relation to the costs of delivering those services. One approach is to measure outcomes of youth receiving mental-health services from their own perspective to achieve value-based measurement of youth mental-health services.  Patient-reported outcome measures (PROMs) are questionnaires filled out by the persons receiving mental-health services themselves, and assess their self-reported health and well-being. PROMs have been shown to be important in evaluating the value of health-care services both at the individual and systems level.  At the individual level, PROMs allow patients and health-care providers to track progress over time. At the systems level, PROMs data can be compiled to evaluate trends between different sites or different health-care services or treatments over time, to help improve quality. Policy-makers can use these comparisons to help pinpoint which services offer the most value.  Given resource constraints, implementing PROMs province-wide in Alberta can improve the value of youth mental-health services at a time when they have become a matter of great urgency. Improving the quality and outcomes for youth and their families in the short term will deliver positive socioeconomic impacts in the future

    Human Interaction: A key to managing disruptive behavior in dementia.

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    The results are part of a larger multi-center, mixed-methods study investigating the effect of environmental design in managing disruptive behavior in dementia. The presentation focuses on data from fifteen (15) discussion groups conducted with families (N = 45) and staff (N= 59) from eight (8) dementia units. Participants were asked to identify the primary obstacles and facilitators for managing behaviors in long-term care facilities. Results stress the importance of human interaction and institutional flexibility. These will be discussed in the context of communication environments and supported by observational data obtained in five (5) of the units

    Meta-analysis of gender performance gaps in undergraduate natural science courses

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    To investigate patterns of gender-based performance gaps, we conducted a meta-analysis of published studies and unpublished data collected across 169 undergraduate biology and chemistry courses. While we did not detect an overall gender gap in performance, heterogeneity analyses suggested further analysis was warranted, so we investigated whether attributes of the learning environment impacted performance disparities on the basis of gender. Several factors moderated performance differences, including class size, assessment type, and pedagogy. Specifically, we found evidence that larger classes, reliance on exams, and undisrupted, traditional lecture were associated with lower grades for women. We discuss our results in the context of natural science courses and conclude by making recommendations for instructional practices and future research to promote gender equity

    Development and preliminary evaluation of a quality of life measure targeted at dementia caregivers

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    <p>Abstract</p> <p>Background</p> <p>Providing care for individuals with a progressive, debilitating condition such as dementia can adversely impact the quality of life (QOL) of informal caregivers. To date, there is no existing caregiver quality of life measure for dementia caregivers with breadth of coverage or that is applicable to caregivers of diverse ethnic backgrounds. The purpose of this study was to develop and evaluate a caregiver-targeted quality-of-life measure (CGQOL) for informal caregivers of persons with dementia that can be used with caregivers from a variety of ethnicities.</p> <p>Methods</p> <p>91 items were field tested by telephone interviews with 179 English-speaking and 21 monolingual Spanish-speaking caregivers of persons with dementia. Repeat interviews were conducted with 71 caregivers. Administration time, scale score distributions, item-scale correlations, reliability, and associations of scales with patient and caregiver demographic and caregiving characteristics were estimated. Structure of associations among scales was examined using exploratory factor analysis.</p> <p>Results</p> <p>Item analysis yielded 80 items distributed across 10 scales, with median administration time of 17 minutes [IQR 13.5–22 minutes] and minimal missing data. There were few floor or ceiling effects in scale score distributions. Internal consistency reliability was ≥ 0.78 for all scales; test-retest reliability (intraclass correlation) estimates exceeded 0.70 for 6 scales. More hours weekly spent in caregiving was uniquely associated with worse quality of life on 8 scales (p's ≤ 0.05). Three higher-order dimensions of caregiving assistance, emotional and social concerns, and spirituality and benefits were identified.</p> <p>Conclusion</p> <p>These preliminary results support subsequent evaluation of test-retest reliability, construct validity, and responsiveness to change of this quality-of-life measure for caregivers from diverse ethnicities.</p

    Cytogenetic and Molecular Predictors of Outcome in Acute Lymphocytic Leukemia: Recent Developments

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    During the last decade a tremendous technologic progress based on genome-wide profiling of genetic aberrations, structural DNA alterations, and sequence variations has allowed a better understanding of the molecular basis of pediatric and adult B/T- acute lymphoblastic leukemia (ALL), contributing to a better recognition of the biological heterogeneity of ALL and to a more precise definition of risk factors. Importantly, these advances identified novel potential targets for therapeutic intervention. This review will be focused on the cytogenetic/molecular advances in pediatric and adult ALL based on recently published articles
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