854 research outputs found

    Examining the Experiences of Community College Students

    Get PDF
    Community colleges often have low graduation and retention rates but are more accessible to individuals from low- and moderate-income backgrounds due to affordable tuition. Receiving financial aid, such as the Pell Grant, has a positive influence on ability to achieve academic goals. The aim of this study was to investigate impeding and strengthening factors that impacted academic goal attainment in community college students eligible for the Pell Grant. Data was collected through face-to-face semi-structured interviews with current financially eligible Pell grant community college students (n=62). The research team conducted thematic analysis guided by empowerment and strength-based theories. Participants reported on the impacts of having parents who are immigrants, economic factors, experiences with staff, and social support systems. Findings reinforce the importance of equitable policy and practice to enhance student completion rates

    Soil Macroinvertebrate Responses to Wildfires in the Blue Ridge Mountains, USA

    Get PDF
    Title: Soil Macroinvertebrate Responses to Wildfires in the Blue Ridge Mountains, USA Authors: 1Madeline N. Olliff, 1Bruce A. Snyder, 2Melanie K. Taylor, and 2Mac A. Callaham 1Georgia College and State University, Milledgeville, Georgia, USA; 2USDA Forest Service, Southern Research Station, Athens, Georgia, USA Abstract: Wildfires are of increasing concern in light of climate change, more frequent late summer droughts, and increasing incidence of human ignitions. There have been few studies examining the effects of wildland fires on soil macroinvertebrates in the Blue Ridge Mountains, in spite of the importance of these animals to soil processes, and their contributions to the biodiversity of these ecosystems. During November and December of 2016, the southeastern USA experienced numerous, large wildfires. These fires offered an opportunity to study the effects of wildland fire on soil macroinvertebrates. We sampled plots from three different wildfires in North Georgia and Tennessee, each plot with five burned plots and five unburned plots. These sites were sampled seasonally from 2017 through 2020. At each plot, on each date, we collected macroinvertebrates by hand sorting both litter (4 m diameter plots) and mineral soil monoliths (30 x 30 x 30 cm) for 30 person-minutes each. All macroinvertebrates were identified to morphospecies. One focal taxon, millipedes, were identified to species. Abundance, species richness, and several diversity metrics (abundance and richness) were calculated to compare the macroinvertebrate communities of the burned areas to those in the unburned areas to better understand their response to fire

    Outbound Medical Tourism from Mongolia: a Qualitative Examination of Proposed Domestic Health System and Policy Responses to this Trend

    Get PDF
    Background: Medical tourism is the practice of traveling across international boundaries in order to access medical care. Residents of low-to-middle income countries with strained or inadequate health systems have long traveled to other countries in order to access procedures not available in their home countries and to take advantage of higher quality care elsewhere. In Mongolia, for example, residents are traveling to China, Japan, Thailand, South Korea, and other countries for care. As a result of this practice, there are concerns that travel abroad from Mongolia and other countries risks impoverishing patients and their families.   Methods: In this paper, we present findings from 15 interviews with Mongolian medical tourism stakeholders about the impacts of, causes of, and responses to outbound medical tourism. These findings were developed using a case study methodology that also relied on tours of health care facilities and informal discussions with citizens and other stakeholders during April, 2012.   Results: Based on these findings, health policy changes are needed to address the outflow of Mongolian medical tourists. Key areas for reform include increasing funding for the Mongolian health system and enhancing the efficient use of these funds, improving training opportunities and incentives for health workers, altering the local culture of care to be more supportive of patients, and addressing concerns of corruption and favouritism in the health system.   Conclusions: While these findings are specific to the Mongolian health system, other low-to-middle income countries experiencing outbound medical tourism will benefit from consideration of how these findings apply to their own contexts. As medical tourism is increasing in visibility globally, continued research on its impacts and context-specific policy responses are needed. &nbsp

    Temperature Affects Hatching Success of Cocoons in the Invasive Asian Earthworm Amynthas agrestis from the Southern Appalachians

    Get PDF
    Invasive Asian earthworms are increasingly common in the eastern USA where they are a major cause of terrestrial ecosystem disturbance. Among these, Amynthas agrestis (Crazy Worm, Alabama Jumper, and other common names) has been shown to alter above- and belowground food webs. Life-history traits of these earthworms are largely unknown, particularly in their invaded range. Here, we sought to answer questions about temperature effects on hatching success for cocoons of this species, using specimens collected from the southern Appalachian Mountains. We conducted 2 experiments investigating the effects of incubation temperature and the effect of varying the duration of cold temperature on hatching success. Of the temperatures tested, we found that cocoons hatched with greatest success at 10 °C, but our tests indicate a long duration at that temperature may be needed to result in an increase in hatching success. These results indicate that temperature and the duration of temperature exposure affect hatching success in this species. While our results contribute to the growing body of knowledge about the life-history traits of invasive Asian earthworms in the eastern US, more research is needed to provide a finer-resolution understanding of the optimum level and duration of temperatures for hatching success of A. agrestis

    Genetic Characterization and Role in Virulence of the Ribonucleotide Reductases of Streptococcus sanguinis

    Get PDF
    Streptococcus sanguinis is a cause of infective endocarditis and has been shown to require a manganese transporter called SsaB for virulence and O2 tolerance. Like certain other pathogens, S. sanguinis possesses aerobic class Ib (NrdEF) and anaerobic class III (NrdDG) ribonucleotide reductases (RNRs) that perform the essential function of reducing ribonucleotides to deoxyribonucleotides. The accompanying paper (Makhlynets, O., Boal, A. K., Rhodes, D. V., Kitten, T., Rosenzweig, A. C., and Stubbe, J. (2014) J. Biol. Chem. 289, 6259–6272) indicates that in the presence of O2, the S. sanguinis class Ib RNR self-assembles an essential diferric-tyrosyl radical (FeIII2-Y•) in vitro, whereas assembly of a dimanganese-tyrosyl radical (MnIII2-Y•) cofactor requires NrdI, and MnIII2-Y• is more active than FeIII2-Y• with the endogenous reducing system of NrdH and thioredoxin reductase (TrxR1). In this study, we have shown that deletion of either nrdHEKF or nrdI completely abolishes virulence in an animal model of endocarditis, whereas nrdD mutation has no effect. The nrdHEKF, nrdI, and trxR1mutants fail to grow aerobically, whereas anaerobic growth requires nrdD. The nrdJgene encoding an O2-independent adenosylcobalamin-cofactored RNR was introduced into the nrdHEKF, nrdI, and trxR1 mutants. Growth of the nrdHEKF and nrdI mutants in the presence of O2 was partially restored. The combined results suggest that MnIII2-Y•-cofactored NrdF is required for growth under aerobic conditions and in animals. This could explain in part why manganese is necessary for virulence and O2 tolerance in many bacterial pathogens possessing a class Ib RNR and suggests NrdF and NrdI may serve as promising new antimicrobial targets

    Activation of Ca2+-activated Cl- current by depolarizing steps in rabbit urethral interstitial cells.

    Get PDF
    Interstitial cells were isolated from strips of rabbit urethra for study using the amphotericin B perforated-patch technique. Depolarizing steps to -30 mV or greater activated a Ca2+ current (ICa), followed by a Ca2+-activated Cl- current, and, on stepping back to -80 mV, large Cl- tail currents were observed. Both currents were abolished when the cells were superfused with Ca2+-free bath solution, suggesting that Ca2+ influx was necessary for activation of the Cl- current. The Cl- current was also abolished when Ba2+ was substituted for Ca2+ in the bath or the cell was dialyzed with EGTA (2 mM). The Cl- current was also reduced by cyclopiazonic acid, ryanodine, 2-aminoethoxydiphenyl borate (2-APB), and xestospongin C, suggesting that Ca2+-induced Ca2+ release (CICR) involving both ryanodine and inositol 1,4,5-trisphosphate receptors contributes to its activation

    Galaxy Zoo: morphological classification of galaxy images from the Illustris simulation

    Get PDF
    Modern large-scale cosmological simulations model the universe with increasing sophistication and at higher spatial and temporal resolutions. These ongoing enhancements permit increasingly detailed comparisons between the simulation outputs and real observational data. Recent projects such as Illustris are capable of producing simulated images that are designed to be comparable to those obtained from local surveys. This paper tests the degree to which Illustris achieves this goal across a diverse population of galaxies using visual morphologies derived from Galaxy Zoo citizen scientists. Morphological classifications provided by these volunteers for simulated galaxies are compared with similar data for a compatible sample of images drawn from the Sloan Digital Sky Survey (SDSS) Legacy Survey. This paper investigates how simple morphological characterization by human volunteers asked to distinguish smooth from featured systems differs between simulated and real galaxy images. Significant differences are identified, which are most likely due to the limited resolution of the simulation, but which could be revealing real differences in the dynamical evolution of populations of galaxies in the real and model universes. Specifically, for stellar masses, a substantially larger proportion of Illustris galaxies that exhibit disk-like morphology or visible substructure, relative to their SDSS counterparts. Toward higher masses, the visual morphologies for simulated and observed galaxies converge and exhibit similar distributions. The stellar mass threshold indicated by this divergent behavior confirms recent works using parametric measures of morphology from Illustris simulated images. When , the Illustris data set contains substantially fewer galaxies that classifiers regard as unambiguously featured. In combination, these results suggest that comparison between the detailed properties of observed and simulated galaxies, even when limited to reasonably massive systems, may be misleading

    Subtask 3.3 - Feasibility of Direct Coal Liquefaction in the Modern Economic Climate

    Get PDF
    Coal liquefaction provides an alternative to petroleum for the production of liquid hydrocarbon-based fuels. There are two main processes to liquefy coal: direct coal liquefaction (DCL) and indirect coal liquefaction (ICL). Because ICL has been demonstrated to a greater extent than DCL, ICL may be viewed as the lower-risk option when it comes to building a coal liquefaction facility. However, a closer look, based on conversion efficiencies and economics, is necessary to determine the optimal technology. This report summarizes historical DCL efforts in the United States, describes the technical challenges facing DCL, overviews Shenhua's current DCL project in China, provides a DCL conceptual cost estimate based on a literature review, and compares the carbon dioxide emissions from a DCL facility to those from an ICL facility

    Potent Host-Directed Small-Molecule Inhibitors of Myxovirus RNA-Dependent RNA-Polymerases

    Get PDF
    Therapeutic targeting of host cell factors required for virus replication rather than of pathogen components opens new perspectives to counteract virus infections. Anticipated advantages of this approach include a heightened barrier against the development of viral resistance and a broadened pathogen target spectrum. Myxoviruses are predominantly associated with acute disease and thus are particularly attractive for this approach since treatment time can be kept limited. To identify inhibitor candidates, we have analyzed hit compounds that emerged from a large-scale high-throughput screen for their ability to block replication of members of both the orthomyxovirus and paramyxovirus families. This has returned a compound class with broad anti-viral activity including potent inhibition of different influenza virus and paramyxovirus strains. After hit-to-lead chemistry, inhibitory concentrations are in the nanomolar range in the context of immortalized cell lines and human PBMCs. The compound shows high metabolic stability when exposed to human S-9 hepatocyte subcellular fractions. Antiviral activity is host-cell species specific and most pronounced in cells of higher mammalian origin, supporting a host-cell target. While the compound induces a temporary cell cycle arrest, host mRNA and protein biosynthesis are largely unaffected and treated cells maintain full metabolic activity. Viral replication is blocked at a post-entry step and resembles the inhibition profile of a known inhibitor of viral RNA-dependent RNA-polymerase (RdRp) activity. Direct assessment of RdRp activity in the presence of the reagent reveals strong inhibition both in the context of viral infection and in reporter-based minireplicon assays. In toto, we have identified a compound class with broad viral target range that blocks host factors required for viral RdRp activity. Viral adaptation attempts did not induce resistance after prolonged exposure, in contrast to rapid adaptation to a pathogen-directed inhibitor of RdRp activity
    • …
    corecore