Cross-shelf and seasonal variation in larval fish assemblages on the southeast United States continental shelf off the coast of Georgia

Seasonal and cross-shelf patterns were investigated in larval fish assemblages on the continental shelf off the coast of Georgia. The influence of environmental factors on larval distributions also was examined, and larval transport processes on the shelf were considered. Ichthyoplankton and environmental data were collected approximately every other month from spring 2000 to winter 2002. Ten stations were repeatedly sampled along a 110-km cross-shelf transect, including four stations in the vicinity of Gray’s Reef National Marine Sanctuary. Correspondence analysis (CA) on untransformed community data identified two seasonal (warm weather [spring, summer, and fall] and winter) and three cross-shelf larval assemblages (inner-, mid-, and outer-shelf ). Five environmental factors (temperature, salinity, density, depth of the water column, and stratification) were related to larval cross-shelf distribution. Specifically, increased water column stratification was associated with the outer-shelf assemblage in spring, summer, and fall. The inner shelf assemblage was associated with generally lower temperatures and lower salinities in the spring and summer and higher salinities in the winter. The three cross-shelf regions indicated by the three assemblages coincided with the location of three primary water masses on the shelf. However, taxa occurring together within an assemblage were transported to different parts of the shelf; thus, transport across the continental shelf off the coast of Georgia cannot be explained solely by twodimensional physical factors

Democracy\u27s Harvest: Resources for Massachusetts Voters\u27 Initiatives and Referendums

Massachusetts initiatives and referendums, based upon a lengthy and complicated constitutional amendment, present legal and historical researchers with a number of questions and issues to resolve. This review of the resources on initiatives and referendums attempts to provide guidance for these researchers, while provoking critical thinking about issues past, present, and future

Thermodynamics of ethylene-vinyl acetate copolymer blends

The purpose of this study was to characterise the miscibility of several poly(ethylene-co-vinyl acetate), EVA, based polymer blends. EVA has many industrial applications and is often present as one of several polymeric components. Consequently, there is considerable interest in the thermodynamics of these blend systems. The thermodynamics of these blends was studied using several techniques: differential scanning calorimetry; phase contrast optical microscopy; small angle neutron scattering and wide angle X-ray scattering. Characterisation was also to include assessing the relative enthalpic and entropic thermodynamic contributions to the Rory-Huggins interaction parameter (%) of these blends. To determine the enthalpic interaction parameter, a "mixing calorimeter" was designed and constructed to measure accurately the "heat of mixing" values on blending these polymers. Free energy interaction parameters were determined from melting point depression and small angle neutron scattering measurements. In all the blends studied, the heat of mixing was endothermic and consequently, the enthalpic interaction parameters were positive i.e. unfavourable to miscibility. Miscibility in these blends can therefore only be achieved by a dominant entropic contribution, favourable to miscibility. Using phase contrast optical microscopy, both miscible and immiscible phase behaviour was observed in this series of blends. This shows good agreement with predictions of miscibility from heat of mixing, melting point and small angle neutron scattering measurements, based on the classical Flory-Huggins lattice theory. Wide angle X-ray scattering and differential scanning calorimetry results have associated miscible blends with crystallisation effects between the blend components. Small angle neutron scattering has been used to determine the concentration and temperature dependence of interaction parameters in a miscible blend. From these values the upper critical solution temperature (UCST) of the blend was predicted. The enthalpic contributions to these interaction parameters show good agreement with experimental values determined from heat of mixing measurements. It was concluded that the classical Flory-Huggins lattice theory (despite its many well documented Limitations) appears to be particularly suited to the thermodynamic characterisation of miscibility in these polymer blends

Vapor phase growth technique and system for several 3-5 compound semiconductors Quarterly technical report

Vapor phase growth technique and system for group 3A and 5A compound semiconductor

The cow and calf : a 4-H beef production project

March, 1953."University of Missouri College of Agriculture and the United States Department of Agriculture Cooperating"--Page 11.Title from caption.Includes "4-H Record" at end

"Need Everyone Helping to Keep Off Because Everyone Helping to Keep On" – reducing harms from cannabis use in remote Indigenous Australian communities involves more than just users

Background: Heavy cannabis use in remote Indigenous Australian communities potentially contributes to existing health disparities. Community members’ perceptions of cannabis harms will support harm-minimization in these settings. Objective: To describe perceived cannabis harms reported by a cohort of Indigenous Australians living in small, isolated communities as an indication of their existing resources for change. Method: Inductive thematic analysis of 407 semi-structured interviews with participants in a cohort study in three remote communities in Cape York in far north Queensland (Australia) revealed major areas of concern about cannabis. Three attitudinal categories were defined according to reported cannabis impacts and urgency for change: 1- “LOW CONCERN” said cannabis was a low priority community issue; 2- “SOME CONCERN” tolerated cannabis use but identified personal or community-level concerns; and 3- “HIGH CONCERN” expressed strong aversion to cannabis and identified serious personal or community-level harms. The characteristics and the patterns of concerns were summarized across the groups. Results: “Category 1- LOW CONCERN” (n¼107), mostly current users, emphasized personal “financial impacts” and “stress.” “Category 2 – SOME CONCERN” (n¼141) perceived community level impacts warranting systematic action, particularly on “employment”; and “Category 3 – HIGH CONCERN” (n¼159), most of the never users, emphasized concerns for families and youth. Irrespective of use history, the cohort reported financial and abstinence-related stress, overlapping alcohol issues and generally endorsed alleviating impacts on children and youth. Conclusion: Nearly ubiquitous experience with cannabis harms and impacts in this cohort suggests resources for harm reduction including family and cultural obligation, stress relief, financial management, and engagement are available across all community members, not just users

Radiation Damage Studies of Silicon Photomultipliers

We report on the measurement of the radiation hardness of silicon photomultipliers (SiPMs) manufactured by Fondazione Bruno Kessler in Italy (1 mm$^2$ and 6.2 mm$^2$), Center of Perspective Technology and Apparatus in Russia (1 mm$^2$ and 4.4 mm$^2$), and Hamamatsu Corporation in Japan (1 mm$^2$). The SiPMs were irradiated using a beam of 212 MeV protons at Massachusetts General Hospital, receiving fluences of up to $3 \times 10^{10}$ protons per cm$^2$ with the SiPMs at operating voltage. Leakage currents were read continuously during the irradiation. The delivery of the protons was paused periodically to record scope traces in response to calibrated light pulses to monitor the gains, photon detection efficiencies, and dark counts of the SiPMs. The leakage current and dark noise are found to increase with fluence. Te leakage current is found to be proportional to the mean square deviation of the noise distribution, indicating the dark counts are due to increased random individual pixel activation, while SiPMs remain fully functional as photon detectors. The SiPMs are found to anneal at room temperature with a reduction in the leakage current by a factor of 2 in about 100 days.Comment: 35 pages, 25 figure

Letter from Charles E. Clough, Staunton, Virginia, to Mrs. Robert J. Davison, Bath, New York, 1914 January 24

https://repository.wellesley.edu/studentcordavison/1104/thumbnail.jp

Case studies in Bayesian microbial risk assessments

<p>Abstract</p> <p>Background</p> <p>The quantification of uncertainty and variability is a key component of quantitative risk analysis. Recent advances in Bayesian statistics make it ideal for integrating multiple sources of information, of different types and quality, and providing a realistic estimate of the combined uncertainty in the final risk estimates.</p> <p>Methods</p> <p>We present two case studies related to foodborne microbial risks. In the first, we combine models to describe the sequence of events resulting in illness from consumption of milk contaminated with VTEC O157. We used Monte Carlo simulation to propagate uncertainty in some of the inputs to computer models describing the farm and pasteurisation process. Resulting simulated contamination levels were then assigned to consumption events from a dietary survey. Finally we accounted for uncertainty in the dose-response relationship and uncertainty due to limited incidence data to derive uncertainty about yearly incidences of illness in young children. Options for altering the risk were considered by running the model with different hypothetical policy-driven exposure scenarios. In the second case study we illustrate an efficient Bayesian sensitivity analysis for identifying the most important parameters of a complex computer code that simulated VTEC O157 prevalence within a managed dairy herd. This was carried out in 2 stages, first to screen out the unimportant inputs, then to perform a more detailed analysis on the remaining inputs. The method works by building a Bayesian statistical approximation to the computer code using a number of known code input/output pairs (training runs).</p> <p>Results</p> <p>We estimated that the expected total number of children aged 1.5-4.5 who become ill due to VTEC O157 in milk is 8.6 per year, with 95% uncertainty interval (0,11.5). The most extreme policy we considered was banning on-farm pasteurisation of milk, which reduced the estimate to 6.4 with 95% interval (0,11). In the second case study the effective number of inputs was reduced from 30 to 7 in the screening stage, and just 2 inputs were found to explain 82.8% of the output variance. A combined total of 500 runs of the computer code were used.</p> <p>Conclusion</p> <p>These case studies illustrate the use of Bayesian statistics to perform detailed uncertainty and sensitivity analyses, integrating multiple information sources in a way that is both rigorous and efficient.</p