Seasonal Habitat Use of The Florida Manatee (Trichecus Manatus Latirostris) In The Crystal River Natural Refuge With Regards To Natural And Anthropogenic Factors

Natural and anthropogenic factors work together to influence species habitat use. Kings Bay in Crystal River, Florida serves as critical habitat for the Florida manatee, but is also used extensively by humans. This study documented the seasonal dispersion and behavioral patterns of manatees in Kings Bay with regards to natural and anthropogenic factors from May 2005-June 2006. Survey stations were established across the bay and the number of manatees, people in the water, and boats were counted. The behavioral patterns of four major states were recorded using focal animal observations. During the winter, manatees aggregated in areas containing both springs and sanctuaries, where human activity was high and vegetation coverage low. In the non-winter, manatees were most abundant away from springs, where there was higher vegetative coverage and lower human activity. In the winter season, manatee spent most of their time resting in sanctuaries with springs, but when found feeding bouts were longer than in the non-winter season. In the non-winter, variation in behavior was attributed more to the lifestyle roles of different age and sex class manatees than to sub-habitat type. The need for sanctuaries that protect feeding sites during the non-winter season is recommended

Life-Cycle Modeling and Environmental Impact Assessment of Commercial Scale Biogas Production

Biogas is becoming an increasingly popular product from the treatment of wastewater, agriculture, food, and municipal solid waste. The process of anaerobic digestion (AD) allows organic waste streams such as sewage sludge, manure, and landfill organics to be converted into usable products such as biogas, fertilizer, and soil amendments. The benefits of resource recovery from waste streams depend on the current economic context and establishing a defined market for value-added products. However, there is a significant challenge in evaluating these opportunities without first understanding the environmental impact associated with various AD resource recovery systems. Applying life cycle assessment (LCA) to commercial biogas production provides a valuable tool for evaluating the environmental impact of waste management processes and assists in economic decision-making. Using life cycle assessment as a basis for evaluating the biogas production at the Swedish Biogas International, LLC (SBI) Facility in Flint, Michigan this study quantifies the environmental benefits of implementing AD at the Flint Water Pollution Control Facility. The study compares the emissions associated with the incineration of biosolids to emissions from Class B land application on a local brownfield site and the use of biogas in an electrical generator to that of upgrading biogas to biomethane. Several other options for the use of AD byproducts are investigated including kiln drying of biosolids, phosphorus recovery, and the growth of energy crops (maize) for use as an AD feedstock. The results are quantified using a dynamic Excel-based model, which incorporates primary data collected at the Flint SBI facility and previous research data from the U.S. Environmental Protection Agency and private sources. The intent of the model is to provide the management of SBI with a quantitative analysis of the environmental impacts of the facility compared to previous operations. The knowledge can be used to optimize the biogas management process and select the best opportunity for biosolids management within the context of the City of Flint, Michigan. The primary environmental impacts investigated were Global Warming Potential, Acidification, and Smog Formation. All scenarios showed a substantial improvement over incineration. Upon termination of incineration, Global Warming Potential is greatly reduced due to avoided N2O emissions. Electricity generation is preferable to biogas upgrading due the credit from avoided emissions from Michigan’s coal intensive energy mix. The alternative and supplemental benefits incur high initial investment costs but could provide additional revenue for SBI while making significant improvements in environmental impacts. Energy crops provide a benefit in the form of carbon sequestration, but maize has a poor biomass to biogas conversion, and so is not an optimal feedstock for AD.Master of ScienceNatural Resources and EnvironmentUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/90871/1/Swedish_Biogas_MP_2012.pd

Bioluminescent Magnetic Nanoparticles as Potential Imaging Agents for Mammalian Spermatozoa

Background: Nanoparticles have emerged as key materials for developing applications in nanomedicine, nanobiotechnology, bioimaging and theranostics. Existing bioimaging technologies include bioluminescent resonance energy transfer-conjugated quantum dots (BRET-QDs). Despite the current use of BRET-QDs for bioimaging, there are strong concerns about QD nanocomposites containing cadmium which exhibits potential cellular toxicity. Results: In this study, bioluminescent composites comprised of magnetic nanoparticles and firefly luciferase (Photinus pyralis) are examined as potential light-emitting agents for imaging, detection, and tracking mammalian spermatozoa. Characterization was carried out using infrared spectroscopy, TEM and cryo-TEM imaging, and ζ-potential measurements to demonstrate the successful preparation of these nanocomposites. Binding interactions between the synthesized nanoparticles and spermatozoon were characterized using confocal and atomic/magnetic force microscopy. Bioluminescence imaging and UV–visible-NIR microscopy results showed light emission from sperm samples incubated with the firefly luciferase-modified nanoparticles. Therefore, these newly synthesized luciferase-modified magnetic nanoparticles show promise as substitutes for QD labeling, and can potentially also be used for in vivo manipulation and tracking, as well as MRI techniques. Conclusions: These preliminary data indicate that luciferase-magnetic nanoparticle composites can potentially be used for spermatozoa detection and imaging. Their magnetic properties add additional functionality to allow for manipulation, sorting, or tracking of cells using magnetic techniques

Examination of relaxin and its receptors expression in pig gametes and embryos

<p>Abstract</p> <p>Background</p> <p>Relaxin is a small peptide also known as pregnancy hormone in many mammals. It is synthesized by both male and female tissues, and its secretions are found in various body fluids such as plasma serum, ovarian follicular fluid, utero-oviduct secretions, and seminal plasma of many mammals, including pigs. However, the presence and effects of relaxin in porcine gametes and embryos are still not well-known. The purpose of this study was to assess the presence of relaxin and its receptors RXFP1 and RXFP2 in pig gametes and embryos.</p> <p>Methods</p> <p>Immature cumulus-oocyte complexes (COCs) were aspirated from sows' ovaries collected at the abattoir. After <it>in vitro</it>-maturation, COCs were <it>in vitro</it>-fertilized and cultured. For studies, immature and mature COCs were separately collected, and oocytes were freed from their surrounding cumulus cells. Denuded oocytes, cumulus cells, mature boar spermatozoa, zygotes, and embryos (cleaved and blastocysts) were harvested for temporal and spatial gene expression studies. Sections of ovary, granulosa and neonatal porcine uterine cells were also collected to use as controls.</p> <p>Results</p> <p>Using both semi-quantitative and quantitative PCRs, relaxin transcripts were not detected in all tested samples, while RXFP1 and RXFP2 mRNA were present. Both receptor gene products were found at higher levels in oocytes compared to cumulus cells, irrespective of the maturation time. Cleaved-embryos contained higher levels of RXFP2 mRNA, whereas, blastocysts were characterized by a higher RXFP1 mRNA content. Using western-immunoblotting or <it>in situ </it>immunofluorescence, relaxin and its receptor proteins were detected in all samples. Their fluorescence intensities were consistently more important in mature oocytes than immature ones. The RXFP1 and RXFP2 signal intensities were mostly located in the plasma membrane region, while the relaxin ones appeared homogeneously distributed within the oocytes and embryonic cells. Furthermore, spermatozoa displayed stronger RXFP2 signal than RXFP1 after western-immunoblotting.</p> <p>Conclusion</p> <p>All together, our findings suggest potential roles of relaxin and its receptors during oocyte maturation, early embryo development, and beyond.</p

SGD-OD: investigating the potential oxygen demand of submarine groundwater discharge in coastal systems.

Submarine groundwater discharge (SGD) supplies nutrients, carbon, metals, and radionuclide tracers to estuarine and coastal waters. One aspect of SGD that is poorly recognized is its direct effect on dissolved oxygen (DO) demand in receiving waters, denoted here as SGD-OD. Sulfate-mediated oxidation of organic matter in salty coastal aquifers produces numerous reduced byproducts including sulfide, ammonia, dissolved organic carbon and nitrogen, methane, and reduced metals. When these byproducts are introduced to estuarine and coastal systems by SGD and are oxidized, they may substantially reduce the DO concentration in receiving waters and impact organisms living there. We consider six estuarine and coastal sites where SGD derived fluxes of reduced byproducts are well documented. Using data from these sites we present a semiquantitative model to estimate the effect of these byproducts on DO in the receiving waters. Without continued aeration with atmospheric oxygen, the study sites would have experienced periodic hypoxic conditions due to SGD-OD. The presence of

Applications of Fluorescent Quantum Dots for Reproductive Medicine and Disease Detection

Understanding the mechanisms associated with fertility and disease management in animals remains challenging. Continuing advances in nanotechnology provide new tools and alternative approaches for the investigation of these mechanisms. Fluorescent quantum dot nanoparticles, for example, have unique physicochemical properties, which allow for in vivo and in vitro imaging in various areas of life sciences. Traditional quantum dots contain heavy metal semiconductor cores, which have raised concern over their potential for toxicity. The majority of available quantum dots today prevent heavy metal release with additional chemical and polymer layers for safe water solubility. In this chapter, the most widely used quantum dots made of cadmium selenide, which possess great potential for real-time imaging in disease detection and reproductive medicine, are discussed

Selection on moral hazard in health insurance

We use employee-level panel data from a single rm to explore the possibility that individuals may select insurance coverage in part based on their anticipated behavioral ( moral hazard ) response to insurance, a phenomenon we label selection on moral hazard. Using a model of plan choice and medical utilization, we present evidence of heterogeneous moral hazard as well as selection on it, and explore some of its implica- tions. For example, we show that, at least in our context, abstracting from selection on moral hazard could lead to over-estimates of the spending reduction associated with introducing a high-deductible health insurance option.National Institute on Aging (NIA (R01 AG032449))National Cancer Institute (U.S.) (Grant SES-0643037)United States. Social Security Administration (grant #5 RRC08098400-03-00)Aluminum Company of AmericaAlfred P. Sloan FoundationJohn D. and Catherine T. MacArthur Foundation (Network on Socioeconomic Status and Health

Crossing Boundaries: Nineteenth-Century Domestic Relations Law and the Merger of Family and Legal History

This essay argues for the need to study the legal history of the American family. It does so by combining a critique of secondary literature in family and legal history with examples from nineteenth-century domestic relations law. These examples, drawn from family law doctrines on seduction under the cover of a marriage promise, runaway marriages, and bastardy, are used to indicate the benefits of adding a sociocultural dimension to legal history and legal and institutional dimensions to family history. Three main themes in the history of nineteenth-century domestic relations law are developed to make these points: the law\u27s particular fabric of issues, its distribution of authorship, and its chronological development. These themes suggest why a full understanding of the legal history of the American family requires crossing the boundaries between legal and family history