A new face on the countryside: Indians and colonists in the Southeastern forest (ecology, environment, Virginia, North Carolina, South Carolina)

Using ecological literature and an ethnohistorical approach, this dissertation examines the nature and extent of environmental change resulting from European colonization in Virginia, the Carolinas, and Georgia.;European explorers in the Southeast saw mixed hardwood forests, pinelands, savannahs, marshlands, and inland swamps. These diverse habitats were home to an infinite variety of wildlife, including whitetailed deer, black bears, wild turkeys, buffalo, elk, and beaver. The landscape had been shaped by long-term ecological change and by varying patterns of topography, rainfall, and fire.;The environment had also been altered by Indians. Southeastern Indians were neither despoilers nor conservators of nature. Seeking subsistence and survival, they fished, farmed, hunted, and periodically burned the woods, all of which affected the various ecosystems.;Early contact between natives and Europeans introduced Old World diseases into the Southeast which killed Indians by the thousands. With their culture torn apart by depopulation, the natives ensured their survival by finding a place within the European system. Indians willingly supplied colonists with animal skins, meat, and medicinal plants, a systematic trade which led to the extinction of buffalo and elk and nearly wiped out beaver, deer, and ginseng.;Agricultural clearing by colonists reshaped local climates. Selective cutting of white and live oak, white cedar, and baldcypress made those trees scarce in settled regions. Naval stores production reduced sizeable tracts of pinelands to patches of scrubby hardwoods.;Commercial agriculture exhausted and eroded soils. Domestic animals destroyed native grasses and woody plants. European grasses and weeds, carried by transplanted livestock, replaced indigenous species. Agriculture and ranching simplified existing relationships between plants and animals, creating an ecologically unstable new South. .;Attributing such changes solely to European capitalism is an oversimplification. Since his arrival in North America, man has been alienated from nature. The innovations of a capitalist economy triggered complex cultural interaction between Indians, colonists, slaves, and the land itself, a dialectic which pushed all three groups toward exploitation of the environment

CONVENIENT ETHERIFICATION USING TRICHLOROACETIMIDATES AND SYNTHESIS OF AMINOSTEROID SHIP INHIBITORS

Alcohols are a common form of functionality in organic chemistry, and are often present in biologically active molecules. The protection of hydroxy groups is crucial in long multi-step synthetic routes, as the unprotected alcohol is typically not compatible with many reagents. Alcohols are often protected as corresponding benzyl ether, which can then be removed when desired to reveal the alcohol functional group. Classic methodology for protection of alcohols as benzyl ethers requires harsh conditions utilizing strong acids and bases, which functions well for simple substrates. In more complex multifunctional molecules this can lead to degradation and side products. Therefore, there is a need for the development of milder conditions for the protection of alcohols. Recently a number of reagents have been developed to form benzyl ethers under mild, neutral conditions that and do not disturb the sensitive functionality in complex molecules. Many of these reagents have been based on imidate-type systems. The most common imidate system, the trichloroacetimidate, is often utilized for the installation of ethers under Lewis acid catalyzed conditions. Given their ready availability, a reevaluation of the reactivity of alcohols and trichloroacetimidates has been undertaken. In many cases, simply heating the imidate with an alcohol in refluxing toluene without an exogenous acid or base is an effective method for the formation of the desired ether. This operationally simple procedure is most effective for trichloroacetimidates that are precursors to highly stabilized cations (i.e. the 4-methoxybenzyl and diphenylmethyl group). The use of this new procedure with a number of acid and base sensitive substrates, which are protected in excellent yield without disturbing the delicate functionality present in these molecules, is presented. Cancer is a group of disorders that are all defined by abnormal cell growth in an organism. This is a very broad set of diseases that can affect multiple organs. While classic cancer treatments have focused on killing all cells that divide quickly, more modern treatments attempt to selectively stop cancer progression by influencing cell signaling pathways. There are many studies about how cancer cells coopt cell signaling pathways and use these systems, which control cell growth in normal cells, to facilitate their own uncontrolled progression. One of the major cell signaling pathways implicated in tumor development is the PI3K pathway, which is governed by the kinase PI3K and the phosphatases PTEN and SHIP. SHIP1 is an SH2-containing inositol 5’-phosphatase found in blood cells that is responsible for the hydrolysis of phosphatidylinositol-3,4,5-trisphosphate to phosphatidylinositol-4,5-bisphosphate. This enzyme is part of a major cellular signaling pathway (the PI3K pathway) that controls many important cellular events such as proliferation, differentiation and adhesion. SHIP1 inhibition has been found to increase blood cell production and slow the growth of blood cancer cells. Certain aminosteroids show selectivity as SHIP1 inhibitors and therefore may have therapeutic applications. In this study, syntheses of a number of aminosteroid derivatives were performed and these compounds are evaluated for their potential as SHIP1 inhibitors

The relationship of total and per-gram rankings in competitive effect to the natural abundance of herbaceous perennials

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75398/1/j.1365-2745.2001.00533.x.pd

STEM II Initiative at Columbus State University

No abstract is available

When it Pays to Rush: Interpreting Morphogen Gradients Prior to Steady-State

During development, morphogen gradients precisely determine the position of gene expression boundaries despite the inevitable presence of fluctuations. Recent experiments suggest that some morphogen gradients may be interpreted prior to reaching steady-state. Theoretical work has predicted that such systems will be more robust to embryo-to-embryo fluctuations. By analysing two experimentally motivated models of morphogen gradient formation, we investigate the positional precision of gene expression boundaries determined by pre-steady-state morphogen gradients in the presence of embryo-to-embryo fluctuations, internal biochemical noise and variations in the timing of morphogen measurement. Morphogens that are direct transcription factors are found to be particularly sensitive to internal noise when interpreted prior to steady-state, disadvantaging early measurement, even in the presence of large embryo-to-embryo fluctuations. Morphogens interpreted by cell-surface receptors can be measured prior to steady-state without significant decrease in positional precision provided fluctuations in the timing of measurement are small. Applying our results to experiment, we predict that Bicoid, a transcription factor morphogen in Drosophila, is unlikely to be interpreted prior to reaching steady-state. We also predict that Activin in Xenopus and Nodal in zebrafish, morphogens interpreted by cell-surface receptors, can be decoded in pre-steady-state.Comment: 18 pages, 3 figure

Differential Effects of Race and Poverty on Ambulatory Care Sensitive Conditions

This study is a continuation of an earlier study that examined hospitalization rates for ambulatory care sensitive (ACS) conditions, as a proxy for quality of care, and found evidence of a racial disparity among African American and White Medicare beneficiaries. The current study sought to determine whether neighborhood socioeconomic status (SES) explained this disparity. Differences in rates of ACS hospitalizations by race were assessed using Cochran-Mantel Haenszel tests and Poisson regression. Unadjusted rate ratios for ACS hospitalization for African Americans vs. Whites were found to be higher in low poverty areas (rate ratio (RR)=1.13; 95% CI (1.08, 1.17)) than in high poverty areas (RR=0.97; 95% CI (0.89, 1.05)). After controlling for various indicators of area SES in multivariate analyses race differences in ACS hospitalization rates persisted. Rural neighborhoods and those with higher percent of non-high school graduates were associated with greater risk of ACS hospitalizations

Reversal of Misfolding: Prion Disease Behavioral and Physiological Impairments Recover following Postnatal Neuronal Deletion of the PrP Gene

The prionoses are fatal neurodegenerative diseases caused by a pathogenic protein, PrP scrapie, that derives from misfolding of a normal form, PrPc. These diseases progress through stages. A new study by Mallucci et al. in this issue of Neuron shows that prion disease may be reversed in mice by selective removal of the gene in neurons after early physiological, cognitive, and pathological features have developed

Physician-scientists in the United States at 2020: Trends and concerns

Physician-scientists comprise a unique and valuable part of the biomedical workforce, but for decades there has been concern about the number of physicians actively engaged in research. Reports have outlined the challenges facing physician-scientists, and programs have been initiated to encourage and facilitate research careers for medically trained scientists. Many of these initiatives have demonstrated successful outcomes, but there has not been a recent summary of the impact of the past decade of effort. This report compiles available data from surveys of medical education and physician research participation to assess changes in the physician-scientist workforce from 2011-2020. Several trends are positive: rising enrollments in MD-PhD programs, greater levels of interest in research careers among matriculating medical students, more research experience during medical school and rising numbers of physicians in academic medicine, and an increase in first R01 grants to physician-scientists. However, there are now decreased levels of interest in research careers among graduating medical students, a steady decline in MDs applying for NIH loan repayment program support, an increased age at first R01 grant success for physicians, and fewer physicians reporting research as their primary work activity: all of these indicators create concern for the stability of the career path. Despite a recommendation by the Physician-Scientist Workforce in 2014 to create real-time reporting on NIH grants and grantees to help the public assess trends, this initiative has not been completed. Better information is still needed to fully understand the status of the physician-scientist workforce, and to assess efforts to stabilize this vulnerable career path