GIS Assisted Problem Analysis of Trail Erosion in Monongahela National Forest

This research investigates the frequency and patterns of trail erosion on purposefully selected natural surface trails in Monongahela National Forest. Trail erosion is considered a non-self-limiting process which degrades trail beds making them unattractive, difficult to travel on, and has the potential to impact local streams with the introduction of silt. Recreation ecology research delineates factors which influence the rate of erosion on a trail into three broad categories: recreational use, environmental conditions, and managerial actions. This study tests the relationship of variables from each of these categories to the local patterns of erosion. Three sampling strategies are used to document the presence of erosion and to characterize recreational use, environmental conditions, and management parameters. Point samples taken at 600-foot intervals along 63 miles of trail provide information on maximum incision, and a problem census of erosion greater than five inches in depth for ten or more feet document the presence and extent of erosion on study trails. Use of over 500 high-quality field reference points collected with a Global Positioning System (GPS) allowed the placement of wheel distances for eroded segments onto trail routes in a Geographic Information System (GIS) for analysis with other secondary GIS data sets. This approach allowed each trail to be segmented into 600-foot linear segments providing a third sampling frame for consideration with the amount of linear erosion per segment as the dependent variable. These equal sized segments provide a manageable landscape scale unit of analysis. Additionally, GIS elevation data enabled the calculation of two independent variables which are new to trail erosion research, Topographic Relative Moisture Index (TRMI) and Estimated Upslope Flow Length (EUFL).;The results of this study indicate trail erosion on the study trails is comparatively lower than other resource areas with occurrences limited to a subset of trails. Regression models show the primary factors influencing erosion rates for the Forest are recreational use, trail grade, low trail alignments, mid-slope trail positions, open canopies, mean annual precipitation, decreased winter temperature, TRIM, and ELF yet the best model only predicted 26% of the occurrences of erosion. Of all the independent variables, average ELF for linear trail segments described the most variance in the incidence of erosion. The significance of this finding is that there is a great need for shortening the distances water is allowed to travel on a trail with either water diversion structure installation and maintenance or trail rerouting. ELF was also influential in the finding that low-gradient trails with limited use displayed disproportionately higher rates of erosion than other trails, a finding not well documented in previous research. As four of the eight significant predictor variables were GIS based, this study shows the usefulness of utilizing GIS in trail erosion research as it provides insights into landscape scale variables that are not easily measured in the field. Furthermore, this approach integrates well with GIS based trail inventory management systems informing maintenance regimens and facilitating long-term trail degradation monitoring

Earthworm population dynamics as influenced by cropping and tillage history

No-tillage farming has become an important practice in many areas of the United States. Because of the loessal soils that exist in West Tennessee and their highly erodible nature, no-till farming is becoming the primary cropping technique with which to reduce erosion and conserve topsoil. Many aspects of no-till farming have been researched in past years; the effects of no-tillage on earthworm population have received little attention in Tennessee agriculture. Earthworms significantly influence the structure and fertility of soils and in turn effect root growth, infiltration of soil water, microbial populations, soil aggregation, and other properties. This research project was conducted to determine and compare the population dynamics of earthworms in cultivated production fields versus no-till production fields. Sites located at the University of Tennessee Milan Experiment Station were chosen for sampling. The sampling was done 4/94, 10/94, and 4/95. Samples for determining the effect of no-till were taken from three no-till and two tilled production fields and from an ongoing experiment containing both no-till and tilled plots. Samples were also taken from a long term no-till cover crop experiment to compare the effects of various covers. Six 30cm X 30cm X 15cm deep volumes of soil were taken from each production field and one sample per plot from the ongoing experiments. Soil samples were taken to determine bulk density, volumetric water content, total carbon, and pH. Surface residue samples were also taken at each no-till sample site. Earthworms were extracted by hand sorting and preserved in 10% formalin solution for identification. Three seperate species were identified: two native species; Diplocardia caroliniana and Bimastos longicinctus and one exotic; Apporectodea trapeszoides No-till cropping systems had a significant effect on earthworm populations for the 10/94 and 4/95 sampling periods and over the entire period due to the availability of food and limited soil disturbance. Length of time in no-till also had a significant effect on population for the 4/94 and 10/94 sampling periods and over the entire sampling period. Cover crop showed no significant difference for the 10/94 and 4/95 periods, but did for the 4/94 sample period. The results of the analysis performed had a high rate of variability overall

Lithofacies and Mineralogy of the Late Wisconsinan Navarre Till in Stark and Wayne Counties, Ohio

Author Institution: Department of Geology, University of AkronThe Navarre Till deposited by ice of the Killbuck lobe in Stark and Wayne counties is the oldest till of late Wisconsinan age in northeastern Ohio. The type section of the Navarre Till is located near the margin of glaciation in Stark County. Interpretations of the diamict at the type locality include a meltout till overlying shale. Other sections in the study area consist of meltout or flow tills which occur as stratified or massive diamicts interbedded with silts, sands, and gravels. Diamict interpreted as lodgement till occurs only at one section

Granularzelltumor des Larynx

Zusammenfassung: Granularzelltumoren (GZT) sind subkutan oder submukös gelegene, gutartige Tumoren neurogenen Ursprungs. Sie treten häufig im Kopf-Hals-Bereich auf, insbesondere in der Zunge. Bisher wurden etwa 200 laryngeale GZT beschrieben. Meist sind dabei die Stimmlippen und die posteriore Glottis betroffen. Eine Unterscheidung von einer chronischen Entzündung oder einem Malignom ist nur mittels Biopsie möglich. Als Therapie der Wahl wird die vollständige Exzision empfohlen, wobei Tumorausdehnung und zu erwartende Morbidität die Radikalität des Vorgehens bestimmen. Bei vollständiger Entfernung sind Rezidive selte

Engineering the semiconductor/oxide interaction for stacking twin suppression in single crystalline epitaxial silicon(111)/insulator/Si(111) heterostructures

The integration of alternative semiconductor layers on the Si material platform via oxide heterostructures is of interest to increase the performance and/or functionality of future Si-based integrated circuits. The single crystalline quality of epitaxial (epi) semiconductor-insulator-Si heterostructures is however limited by too high defect densities, mainly due to a lack of knowledge about the fundamental physics of the heteroepitaxy mechanisms at work. To shed light on the physics of stacking twin formation as one of the major defect mechanisms in (111)-oriented fcc-related heterostructures on Si(111), we report a detailed experimental and theoretical study on the structure and defect properties of epi-Si(111)/Y2O 3/Pr2O3/Si(111) heterostructures. Synchrotron radiation-grazing incidence x-ray diffraction (SR-GIXRD) proves that the engineered Y2O3/Pr2O3 buffer dielectric heterostructure on Si(111) allows control of the stacking sequence of the overgrowing single crystalline epi-Si(111) layers. The epitaxy relationship of the epi-Si(111)/insulator/Si(111) heterostructure is characterized by a type A/B/A stacking configuration. Theoretical ab initio calculations show that this stacking sequence control of the heterostructure is mainly achieved by electrostatic interaction effects across the ionic oxide/covalent Si interface (IF). Transmission electron microscopy (TEM) studies detect only a small population of misaligned type B epi-Si(111) stacking twins whose location is limited to the oxide/epiSi IF region. Engineering the oxide/semiconductor IF physics by using tailored oxide systems opens thus a promising approach to grow heterostructures with well-controlled properties. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft

Development of a Health-Related Quality of Life Questionnaire (HRQL) for patients with Extremity Soft Tissue Infections (ESTI)

BACKGROUND: Past clinical trials of antimicrobial treatment in soft tissue infections have focused on non-standardized clinical and physiological outcome variables, and have not considered the subjective experience of patients. The objective of this study was to develop a health-related quality of life questionnaire (HRQL) for patients with extremity soft tissue infections (ESTI) for future use in clinical trials. METHODS: The design of this study followed published guidelines and included item generation, item reduction, and questionnaire preparation. Study subjects were consenting English-speaking adults with acute ESTI requiring prescription of at least two days of outpatient intravenous antibiotic therapy. RESULTS: A list of 49 items that adversely impact the quality of life of patients with ESTI was generated by literature review, informal health professional feedback, and semi-structured interviews with twenty patients. A listing of these items was then administered to 95 patients to determine their relative importance on quality of life. A questionnaire was prepared that included the twenty most important items with a 5-point Likert scale response. Questionnaire domains included physical symptoms, problems performing their activities of daily living, impairment of their emotional functioning, and difficulties in their social interactions as related to their ESTI. The final questionnaire was pre-tested on a further ten patients and was named the ESTI-Score. CONCLUSION: The ESTI-Score is a novel instrument designed to quantify the impact of ESTI on quality of life. Future study is required to determine its validity and responsiveness before use as an outcome measure in clinical trials

HACD1, a regulator of membrane composition and fluidity, promotes myoblast fusion and skeletal muscle growth

The reduced diameter of skeletal myofibres is a hallmark of several congenital myopathies, yet the underlying cellular and molecular mechanisms remain elusive. In this study, we investigate the role of HACD1/PTPLA, which is involved in the elongation of the very long chain fatty acids, in muscle fibre formation. In humans and dogs, HACD1 deficiency leads to a congenital myopathy with fibre size disproportion associated with a generalized muscle weakness. Through analysis of HACD1-deficient Labradors, Hacd1-knockout mice, and Hacd1-deficient myoblasts, we provide evidence that HACD1 promotes myoblast fusion during muscle development and regeneration. We further demonstrate that in normal differentiating myoblasts, expression of the catalytically active HACD1 isoform, which is encoded by a muscle-enriched splice variant, yields decreased lysophosphatidylcholine content, a potent inhibitor of myoblast fusion, and increased concentrations of ≥C18 and monounsaturated fatty acids of phospholipids. These lipid modifications correlate with a reduction in plasma membrane rigidity. In conclusion, we propose that fusion impairment constitutes a novel, non-exclusive pathological mechanism operating in congenital myopathies and reveal that HACD1 is a key regulator of a lipid-dependent muscle fibre growth mechanism

Microplastic in Surface Waters of Urban Rivers: Concentration, Sources, and Associated Bacterial Assemblages

The ecological dynamics of microplastic (\u3c5 mm) are well documented in marine ecosystems, but the sources, abundance, and ecological role of microplastic in rivers are unknown and likely to be substantial. Microplastic fibers (e.g., synthetic fabrics) and pellets (e.g., abrasives in personal care products) are abundant in wastewater treatment plant (WWTP) effluent, and can serve as a point source of microplastic in rivers. The buoyancy, hydrophobic surface, and long transport distance of microplastic make it a novel substrate for the selection and dispersal of unique microbial assemblages. We measured microplastic concentration and bacterial assemblage composition on microplastic and natural surfaces upstream and downstream of WWTP effluent sites at nine rivers in Illinois, United States. Microplastic concentration was higher downstream of WWTP effluent outfall sites in all but two rivers. Pellets, fibers, and fragments were the dominant microplastic types, and polymers were identified as polypropylene, polyethylene, and polystyrene. Mean microplastic flux was 1,338,757 pieces per day, although the flux was highly variable among nine sites (min = 15,520 per day, max = 4,721,709 per day). High-throughput sequencing of 16S rRNA genes showed bacterial assemblage composition was significantly different among microplastic, seston, and water column substrates. Microplastic bacterial assemblages had lower taxon richness, diversity, and evenness than those on other substrates, and microplastic selected for taxa that may degrade plastic polymers (e.g., Pseudomonas) and those representing common human intestinal pathogens (e.g., Arcobacter). Effluent from WWTPs in rivers is an important component of the global plastic “life cycle,” and microplastic serves as a novel substrate that selects and transports distinct bacterial assemblages in urban rivers. Rates of microplastic deposition, consumption by stream biota, and the metabolic capacity of microplastic biofilms in rivers are unknown and merit further research