The Ecological Role of Mesopredators and the Long-Term Effects of Mesopredator Control

Until approximately 20 years ago, mammalian predators were actively pursued by hunters and trappers for both sport and economic gain. However, during the past two decades fur prices have fallen precipitously, and sport hunting and trapping of mammalian predators is at an all-time low. Some suggest that decreased hunting and trapping pressure on mesomammal predators (e.g., raccoons, opossums, bobcats, foxes, coyotes, etc; hereafter, mesopredators) has resulted in increased mesopredator populations and a decline in many prey species. The role of mesopredators within southern forests is controversial, and there are few empirical studies on which to base management and political decisions regarding predation issues. Moreover, the few studies that do exist focus on the response of a single species or are of too short duration to fully understand the long-term effects of removal efforts. This study will provide empirical, long-term information on the ecological role of mesopredators. Our study uses mesopredator exclosures to experimentally explore the role of mesopredators within the broader wildlife community by artificially reducing mesopredator populations. Because we are using exclosures (electric fences specifically designed to exclude mesopredators, without restricting target prey species), there will be no need to sacrifice mesopredators to accomplish study objectives. Effects of mesopredators on avian, gopher tortoise, and small mammal population dynamics are of primary interest. However, we are also monitoring snake and raptor populations to determine how mesopredators affect their numbers and distribution and whether they, in tum, influence the dynamics of other wildlife populations

Rules versus Discretion in Committee Decision Making: An Application to the 2001 RAE for UK Economics Departments

The question of rules versus discretion has generated a great deal of debate in many areas of the social sciences. Recently, much of the discussion among academics and stakeholders about the assessment of research in UK higher education institutions has focused on the means that should be used to determine research quality. We present a model of committee decision-making when both rules and discretion are available. Some of the predictions of the model are tested empirically using the UK RAE 2001 results

Activation and discovery of earth-abundant metal catalysts using sodium tert-butoxide

First-row, earth-abundant metals offer an inexpensive and sustainable alternative to precious-metal catalysts. As such, iron and cobalt catalysts have garnered interest as replacements for alkene and alkyne hydrofunctionalization reactions. However, these have required the use of air- and moisture-sensitive catalysts and reagents, limiting both adoption by the non-expert as well as applicability, particularly in industrial settings. Here, we report a simple method for the use of earth-abundant metal catalysts by general activation with sodium tert-butoxide. Using only robust air- and moisture-stable reagents and pre-catalysts, both known and, significantly, novel catalytic activities have been successfully achieved, covering hydrosilylation, hydroboration, hydrovinylation, hydrogenation and [2π+2π] alkene cycloaddition. This activation method allows for the easy use of earth-abundant metals, including iron, cobalt, nickel and manganese, and represents a generic platform for the discovery and application of non-precious metal catalysis

HIV-1 Nef Protein Structures Associated with Brain Infection and Dementia Pathogenesis

The difference between regional rates of HIV-associated dementia (HAD) in patients infected with different subtypes of HIV suggests that genetic determinants exist within HIV that influence the ability of the virus to replicate in the central nervous system (in Uganda, Africa, subtype D HAD rate is 89%, while subtype A HAD rate is 24%). HIV-1 nef is a multifunctional protein with known toxic effects in the brain compartment. The goal of the current study was to identify if specific three-dimensional nef structures may be linked to patients who developed HAD. HIV-1 nef structures were computationally derived for consensus brain and non-brain sequences from a panel of patients infected with subtype B who died due to varied disease pathologies and consensus subtype A and subtype D sequences from Uganda. Site directed mutation analysis identified signatures in brain structures that appear to change binding potentials and could affect folding conformations of brain-associated structures. Despite the large sequence variation between HIV subtypes, structural alignments confirmed that viral structures derived from patients with HAD were more similar to subtype D structures than to structures derived from patient sequences without HAD. Furthermore, structures derived from brain sequences of patients with HAD were more similar to subtype D structures than they were to their own non-brain structures. The potential finding of a brain-specific nef structure indicates that HAD may result from genetic alterations that alter the folding or binding potential of the protein

Soluble and Cell-Associated Insulin Receptor Dysfunction Correlates with Severity of HAND in HIV-Infected Women

Blood sugar metabolism abnormalities have been identified in HIV-infected individuals and associated with HIV-associated neurocognitive disorders (HAND). These abnormalities may occur as a result of chronic HIV infection, long-term use of combined antiretroviral treatment (CART), aging, genetic predisposition, or a combination of these factors, and may increase morbidity and mortality in this population.To determine if changes in soluble and cell-associated insulin receptor (IR) levels, IR substrate-1 (IRS-1) levels, and IRS-1 tyrosine phosphorylation are associated with the presence and severity of HAND in a cohort of HIV-seropositive women.This is a retrospective cross-sectional study using patient database information and stored samples from 34 HIV-seropositive women and 10 controls without history of diabetes from the Hispanic-Latino Longitudinal Cohort of Women. Soluble IR subunits [sIR, ectodomain (α) and full-length or intact (αβ)] were assayed in plasma and CSF samples by ELISA. Membrane IR levels, IRS-1 levels, and IRS-1 tyrosine phosphorylation were analyzed in CSF white cell pellets (WCP) using flow cytometry. HIV-seropositive women had significantly increased levels of intact or full-length sIR in plasma (p<0.001) and CSF (p<0.005) relative to controls. Stratified by HAND, increased levels of full-length sIR in plasma were associated with the presence (p<0.001) and severity (p<0.005) of HAND. A significant decrease in IRS-1 tyrosine-phosphorylation in the WCP was also associated with the presence (p<0.02) and severity (p<0.02) of HAND.This study provides evidence that IR secretion is increased in HIV-seropositive women, and increased IR secretion is associated with cognitive impairment in these women. Thus, IR dysfunction may have a role in the progression of HAND and could represent a biomarker for the presence and severity of HAND

Clinical potential of mechlorethamine gel for the topical treatment of mycosis fungoides-type cutaneous T-cell lymphoma: a review on current efficacy and safety data

Kendall Liner,1 Celeste Brown,2 Laura Y McGirt3 1Division of Dermatology, Medical College of Georgia at Augusta Health, Augusta, GA, USA; 2School of Medicine, University of North Carolina at Chapel Hill, Carolinas Medical Center, Charlotte, NC, USA; 3Department of Hematology/Oncology, Levine Cancer Institute, Carolinas Medical Center, Charlotte, NC, USA Abstract: Nitrogen mustard is a chemotherapeutic agent that has a well-documented safety and efficacy profile in the treatment of cutaneous T-cell lymphoma. Development of nitrogen mustard formulations and treatment regimens has been studied extensively over the last 40&nbsp;years. In the last 5 years, a new gel formulation has been developed that is associated with a decrease in delayed hypersensitivity reactions. The authors in this review found that while the gel formulation may result in a decrease of allergic contact dermatitis, this advantage has been replaced by a higher number of irritant contact reactions and a decrease in complete response rate. The gel formulation has a complete response rate of 13.8%, which is a decrease in efficacy when compared to aqueous-based preparations of similar concentrations. Keywords: mycosis fungoides, nitrogen mustard, mechlorethamine gel, cutaneous T-cell lymphoma, CTCL, Valchlor&reg