Development and Application of a Thermistor Current Meter

This report provides details for the construction of a hot-bead thermistor current meter which is capable of measuring water velocities on a millimeter spatial scale and for the construction of a compact and accurate calibration system. Hot-bead thermistor current meters can be built with response times of 200 ms capable of measuring velocities between 0.1 and 80 cm s-1. The construction of a sturdy probe for application in lotic systems such as high gradient Hawaiian streams was achieved by the use of heavy-duty acrylic tubing, small stainless steel gas-chromatography tubing, and flexible Tygon spaghetti tubing. An acrylic handle anchors the electrical cable at one end and the thermistors at the other. The following criteria were central to the development of the calibration system a accurate calibration b compact unit for storage and use in limited laboratory space c leak-proof system d inexpensive design requirement for readily available materials and e construction requirements for the use of hand tools. The thermistor current meter has been used to measure velocities in the water column and around various substrate features in riverine habitats. More detailed spatial velocity measurements were made in streams by dividing a habitat into small grid cells. With fine spatial scales e.g., grid sizes of 200 to 300 cm 2 or less and repetitive sampling under varying water flow conditions, insights into relationships between various spatial and temporal characteristics of microhabitat velocities were made. The current meter has been used to determine ambient velocity profiles around a variety of benthic stream

The Role of Infaunal and Epifaunal Suspension Feeding Macrofauna on Rates of Benthic-Pelagic Coupling in a Southeastern Estuary.

This research investigated the effects of two suspension feeding bivalves, the infaunal Rangia cuneata, and the epifaunal Crassostrea virginica, on benthic-pelagic coupling in Fourleague Bay, LA, a river-dominated estuary. A continuous-flow microcosm system was developed to overcome recognized limitations of batch methodology and to facilitate manipulations designed to investigate the ecological role of benthic macrofauna. Experiments comparing traditional batch methodology to continuous-flow methodology indicated that rates of benthic processes were consistently greater when measured using continuous-flow methodology. Examinations of concentrations indicated that differences were due to concentration gradients which departed from ambient over time in the batch cores. Over an annual cycle, both species significantly increased rates and altered patterns of benthic exchange of both particulate and dissolved materials. The magnitude of the change relative to ambient sediment rates varied with season and with the faunal community. Weight-rate regressions indicated that increases were accounted for by individual bivalve metabolism in most cases. The effects of both species on benthic processes resulted in significant changes in stoichiometric ratios when compared to those of the sediment alone, potentially ameliorating water-column phosphate and nitrogen limitation at different times of the annual cycle. Differences between the effects of these species were not entirely due to differences in their respective functional group; results suggested a need for the inclusion of a relative measure of metabolic activity when predicting a species effect on its environment. A framework, in the form of a dynamic simulation model, was developed in order to evaluate these rates relative to other nutrient sources and sinks in the context of ecosystem function. Model simulations addressed the influence of the oyster community on NH\sb4 distributions in the lower Fourleague Bay. Results indicated that riverine input was the primary determinant of observed NH\sb4 distributions in the spring, while in fall, the release of NH\sb4 by the oysters was the most important factor determining water-column concentrations. As primary production rates peak in this area of the bay in the fall, it was suggested that the oyster community plays the primary role in supporting these high production rates

Development and preliminary testing of the psychosocial adjustment to hereditary diseases scale

Background: The presence of Lynch syndrome (LS) can bring a lifetime of uncertainty to an entire family as members adjust to living with a high lifetime cancer risk. The research base on how individuals and families adjust to genetic-linked diseases following predictive genetic testing has increased our understanding of short-term impacts but gaps continue to exist in knowledge of important factors that facilitate or impede long-term adjustment. The failure of existing scales to detect psychosocial adjustment challenges in this population has led researchers to question the adequate sensitivity of these instruments. Furthermore, we have limited insight into the role of the family in promoting adjustment. Methods: The purpose of this study was to develop and initially validate the Psychosocial Adjustment to Hereditary Diseases (PAHD) scale. This scale consists of two subscales, the Burden of Knowing (BK) and Family Connectedness (FC). Items for the two subscales were generated from a qualitative data base and tested in a sample of 243 participants from families with LS. Results: The Multitrait/Multi-Item Analysis Program-Revised (MAP-R) was used to evaluate the psychometric properties of the PAHD. The findings support the convergent and discriminant validity of the subscales. Construct validity was confirmed by factor analysis and Cronbach’s alpha supported a strong internal consistency for BK (0.83) and FC (0.84). Conclusion: Preliminary testing suggests that the PAHD is a psychometrically sound scale capable of assessing psychosocial adjustment. We conclude that the PAHD may be a valuable monitoring tool to identify individuals and families who may require therapeutic interventions

Urokinase-type plasminogen activator and arthritis progression: role in systemic disease with immune complex involvement

INTRODUCTION: Urokinase-type plasminogen activator (u-PA) has been implicated in fibrinolysis, cell migration, latent cytokine activation, cell activation, T-cell activation, and tissue remodeling, all of which are involved in the development of rheumatoid arthritis. Previously, u-PA has been reported to play a protective role in monoarticular arthritis models involving mBSA as the antigen, but a deleterious role in the systemic polyarticular collagen-induced arthritis (CIA) model. The aim of the current study is to determine how u-PA might be acting in systemic arthritis models. METHODS: The CIA model and bone marrow chimeras were used to determine the cellular source of u-PA required for the arthritis development. Gene expression of inflammatory and destructive mediators was measured in joint tissue by quantitiative PCR and protein levels by ELISA. The requirement for u-PA in the type II collagen mAb-induced arthritis (CAIA) and K/BxN serum transfer arthritis models was determined using u-PA(-/-) mice. Neutrophilia was induced in the peritoneal cavity using either ovalbumin/anti-ovalbumin or the complement component C5a. RESULTS: u-PA from a bone marrow-derived cell was required for the full development of CIA. The disease in u-PA(-/-) mice reconstituted with bone marrow from C57BL/6 mice was indistinguishable from that in C57BL/6 mice, in terms of clinical score, histologic features, and protein and gene expression of key mediators. u-PA(-/-) mice were resistant to both CAIA and K/BxN serum transfer arthritis development. u-PA(-/-) mice developed a reduced neutrophilia and chemokine production in the peritoneal cavity following ovalbumin/anti-ovalbumin injection; in contrast, the peritoneal neutrophilia in response to C5a was u-PA independent. CONCLUSIONS: u-PA is required for the full development of systemic arthritis models involving immune complex formation and deposition. The cellular source of u-PA required for CIA is bone marrow derived and likely to be of myeloid origin. For immune complex-mediated peritonitis, and perhaps some other inflammatory responses, it is suggested that the u-PA involvement may be upstream of C5a signaling

East Bay Coalition for the Homeless: Branding Study and Marketing Strategy

There are a number of potential positioning strategies. The two which make the most sense for the EBCH are to “position the EBCH away from others in the category” and to “position the EBCH as unique.” These strategies have the advantage of setting the EBCH apart from the other organizations that address homelessness. Occupying its own “position” in the minds of potential and current donors is not only an effective communications/marketing strategy but also a less costly one because it avoids head-to-head competition and comparisons

Inhibition of apoptosis in neuronal cells infected with Chlamydophila (Chlamydia) pneumoniae

Background Chlamydophila (Chlamydia) pneumoniae is an intracellular bacterium that has been identified within cells in areas of neuropathology found in Alzheimer disease (AD), including endothelia, glia, and neurons. Depending on the cell type of the host, infection by C. pneumoniae has been shown to influence apoptotic pathways in both pro- and anti-apoptotic fashions. We have hypothesized that persistent chlamydial infection of neurons may be an important mediator of the characteristic neuropathology observed in AD brains. Chronic and/or persistent infection of neuronal cells with C. pneumoniae in the AD brain may affect apoptosis in cells containing chlamydial inclusions. Results SK-N-MC neuroblastoma cells were infected with the respiratory strain of C. pneumoniae, AR39 at an MOI of 1. Following infection, the cells were either untreated or treated with staurosporine and then examined for apoptosis by labeling for nuclear fragmentation, caspase activity, and membrane inversion as indicated by annexin V staining. C. pneumoniae infection was maintained through 10 days post-infection. At 3 and 10 days post-infection, the infected cell cultures appeared to inhibit or were resistant to the apoptotic process when induced by staurosporine. This inhibition was demonstrated quantitatively by nuclear profile counts and caspase 3/7 activity measurements. Conclusion These data suggest that C. pneumoniae can sustain a chronic infection in neuronal cells by interfering with apoptosis, which may contribute to chronic inflammation in the AD brai

Lynch syndrome: barriers to and facilitators of screening and disease management

Background Lynch syndrome is a hereditary cancer with confirmed carriers at high risk for colorectal (CRC) and extracolonic cancers. The purpose of the current study was to develop a greater understanding of the factors influencing decisions about disease management post-genetic testing. Methods The study used a grounded theory approach to data collection and analysis as part of a multiphase project examining the psychosocial and behavioral impact of predictive DNA testing for Lynch syndrome. Individual and small group interviews were conducted with individuals from 10 families with the MSH2 intron 5 splice site mutation or exon 8 deletion. The data from confirmed carriers (n = 23) were subjected to re-analysis to identify key barriers to and/or facilitators of screening and disease management. Results Thematic analysis identified personal, health care provider and health care system factors as dominant barriers to and/or facilitators of managing Lynch syndrome. Person-centered factors reflect risk perceptions and decision-making, and enduring screening/disease management. The perceived knowledge and clinical management skills of health care providers also influenced participation in recommended protocols. The health care system barriers/facilitators are defined in terms of continuity of care and coordination of services among providers. Conclusions Individuals with Lynch syndrome often encounter multiple barriers to and facilitators of disease management that go beyond the individual to the provider and health care system levels. The current organization and implementation of health care services are inadequate. A coordinated system of local services capable of providing integrated, efficient health care and follow-up, populated by providers with knowledge of hereditary cancer, is necessary to maintain optimal health