1,035 research outputs found

    Seed Yield Prediction Models of Four Common Moist-Soil Plant Species in Texas

    Get PDF
    Seed production by moist-soil plant species often varies within and among managed wetlands and on larger landscapes. Quantifying seed production of moist-soil plants can be used to evaluate wetland management strategies and estimate wetland energetic carrying capacity, specifically for waterfowl. In the past, direct estimation techniques were used, but due to excessive personnel and time costs, other indirect methods have been developed. Because indirect seed yield models do not exist for moist-soil plant species in east-central or coastal Texas, we developed direct and indirect methods to model seed production on regional managed wetlands. In September 2004 and 2005, we collected Echinochloa crusgalli (barnyard grass), E. walterii (wild millet), E. colona (jungle rice), and Oryza sativa (cultivated rice) for phytomorphological measurements and seed yield modeling. Initial simple linear and point of origin regression analyses demonstrate strong relationships (P \u3c 0.001) among phytomorphological and dot grid methods in predicting seed production for all four species. These models should help regional wetland managers evaluate moist-soil management success and create models for seed production for other moist-soil plants in this region

    Decomposition of Three Common Moist-Soil Managed Wetland Plant Species

    Get PDF
    Moist-soil wetland management is used to precisely control delivery, duration, and timing of water addition to, and removal from, managed wetlands with targeted responses including germination and growth of desirable moist-soil plant species. Similarly, water delivery and removal drives decomposition of moist-soil plants as well as nutrient cycling within these systems, which is a key driver of productivity in such managed wetlands. Through deployment of litter bags, we examined rate of mass loss and decay coefficients of three locally abundant moist-soil annual species that are potentially valuable wintering-waterfowl food sources (nodding smartweed Persicaria lapathifolia, red-rooted flatnut sedge Cyperus erythrorhizos, and toothcup Ammannia coccinea) within man-made moist-soil managed wetlands on the Richland Creek Wildlife Management Area in East-central Texas. All three species lost nearly 100% of their mass during an 11-mo deployment period, where rate of mass lost and decay coefficient rates were driven by time, because all moist-soil managed wetlands used were inundated for the duration of this study. Plant materials exposed to persistent inundation in shallow wetlands exhibited rates of mass loss typical of the first two stages of decomposition, during which a majority of plant material mass was lost. However, during this study, typical inundation and drawdown regimes were not implemented, which may have delayed or prolonged decomposition processes, because litter bags of focal species were inundated for the duration of this study. Both locally and regionally specific moist-soil management hydroperiod manipulation should include both drawdown and inundation, to incorporate temporal transitions between these conditions. Such practices will allow wetland managers to more expeditiously meet plant management and waterfowl food production goals within moist-soil managed wetlands

    Influence of providers and nurses on completion of non-targeted HIV screening in an urgent care setting

    Get PDF
    Introduction: Despite recommendations by the Centers for Disease Control (CDC) that all adults be offered non-targeted HIV screening in all care settings, screening in acute-care settings remains unacceptably low. We performed an observational study to evaluate an HIV screening pilot in an academic-community partnership health center urgent care clinic. Methods: We collected visit data via encounter forms and demographic and laboratory data from electronic medical records. A post-pilot survey of perceptions of HIV screening was administered to providers and nurses. Multivariable analysis was used to identify factors associated with completion of testing. Results: Visit provider and triage nurse were highly associated with both acceptance of screening and completion of testing, as were younger age, male gender, and race/ethnicity. 23.5% of patients completed tests, although 36.0% requested screening; time constraints as well as risk perceptions by both the provider and patient were cited as limiting completion of screening. Post-pilot surveys showed mixed support for ongoing HIV screening in this setting by providers and little support by nurses. Conclusions: Visit provider and triage nurse were strongly associated with acceptance of testing, which may reflect variable opinions of HIV screening in this setting by clinical staff. Among patients accepting screening, visit provider remained strongly associated with completion of testing. Despite longstanding recommendations for non-targeted HIV screening, further changes to improve the testing and results process, as well as provider education and buy-in, are needed to improve screening rates

    MEK Inhibition Enhances Paclitaxel-induced Tumor Apoptosis

    Get PDF
    The anti-cancer drug paclitaxel (Taxol) alters microtubule assembly and activates pro-apoptotic signaling pathways. Previously, we and others found that paclitaxel activates endogenous JNK in tumor cells, and the activation of JNK contributes to tumor cell apoptosis. Here we find that paclitaxel activates the prosurvival MEK/ERK pathway, which conversely may compromise the efficacy of paclitaxel. Hence, a combination treatment of paclitaxel and MEK inhibitors was pursued to determine whether this treatment could lead to enhanced apoptosis. The inhibition of MEK/ERK with a pharmacologic inhibitor, U0126, together with paclitaxel resulted in a dramatic enhancement of apoptosis that is four times more than the additive value of the two drugs alone. Enhanced apoptosis was verified by the terminal transferase-mediated dUTP nick end labeling assay, by an enzyme-linked immunosorbent assay for histone-associated DNA fragments, and by flow cytometric analysis for DNA content. Specificity of the pharmacologic inhibitor was confirmed by the use of (a) a second MEK/ERK inhibitor and (b) a transdominant-negative MEK. Enhanced apoptosis was verified in breast, ovarian, and lung tumor cell lines, suggesting this effect is not cell type-specific. This is the first report of enhanced apoptosis detected in the presence of paclitaxel and MEK inhibition and suggests a new anticancer strategy

    AN UPDATED DISTRIBUTION MAP FOR THE LOWER COLORADO RIVER VALLEY POPULATION OF GREATER SANDHILL CRANES

    Get PDF
    The U.S. Fish and Wildlife Service (USFWS) recognizes 6 migratory populations of sandhill cranes (Grus canadensis) in the United States, 4 of which occur in or west of the Rocky Mountains. Traditionally the Lower Colorado River Valley Population (LCRVP; greater sandhill crane [G. c. tabida]) was thought to be distributed across the Imperial (California) and Lower Colorado River (Arizona) Valleys, southward into Mexico via the Colorado River delta in winter and northeastern Nevada (Elko and White Pine Counties) during summer. Conservation and management concern exists over known distribution based on winter and summer surveys because discrepancies exist between the number of individuals counted on winter and summer termini. In 2014 the USFWS initiated a mark-recapture program on the LCRVP to aid in the development of long-term management of this least abundant greater sandhill crane population. The objective of this paper is to update the known distribution of the LCRVP from greater sandhill cranes by using platform transmitter terminals (PTTs). We captured 44 individual greater sandhill cranes and equipped 22 with PTTs on the wintering and summering grounds in the Imperial and Lower Colorado River Valleys and west-central Idaho, 2014-2015. Our updated distribution map from 18 of 22 PTT-tagged individuals identified several new summer locations extending north and west into west-central Idaho and numerous new migratory locations extending east into Utah. We also confirmed winter locations on the Gila River southwest of Phoenix, Arizona. The extent of the distribution of the LCRVP extends farther north and east than previously expected and, most importantly, overlaps with areas commonly affiliated with the Central Valley and Rocky Mountain Populations in the Intermountain West

    Improving Access and Mental Health For Youth Using Smart Technologies

    Get PDF
    The overall objective of this research is to evaluate the use of a mobile health smartphone application (app) to improve the mental health of youth between the ages of 14 and 25 years, with symptoms of anxiety and/or depression. This project includes 122 youth who are accessing outpatient mental health services at one of three hospitals and two community agencies. The youth and care providers are using the Smart technology to enhance care. The technology uses mobile questionnaires (QnairesTM) to help promote self-assessment and track changes to support the plan of care. The youth were provided a smartphone and talk/text/data plan, if needed. The majority of participants identified themselves as Caucasian (73.5%). Expectedly, the demographics revealed that Anxiety Disorders and Mood Disorders were highly prevalent within the sample (73.6% and 66.9% respectively). Findings from the qualitative summary established that both staff and youth found having a smartphone and data plan beneficial. Demographic variables such as age, sex, mental health and physical health did not predict which youth were more likely to use the application

    Improving Access and Mental Health for Youth Through Virtual Models of Care

    Get PDF
    The overall objective of this research is to evaluate the use of a mobile health smartphone application (app) to improve the mental health of youth between the ages of 14–25 years, with symptoms of anxiety/depression. This project includes 115 youth who are accessing outpatient mental health services at one of three hospitals and two community agencies. The youth and care providers are using eHealth technology to enhance care. The technology uses mobile questionnaires to help promote self-assessment and track changes to support the plan of care. The technology also allows secure virtual treatment visits that youth can participate in through mobile devices. This longitudinal study uses participatory action research with mixed methods. The majority of participants identified themselves as Caucasian (66.9%). Expectedly, the demographics revealed that Anxiety Disorders and Mood Disorders were highly prevalent within the sample (71.9% and 67.5% respectively). Findings from the qualitative summary established that both staff and youth found the software and platform beneficial

    Imaging along-strike variations in mechanical properties of the Gofar transform fault, East Pacific Rise

    Get PDF
    Author Posting. © American Geophysical Union, 2014. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Solid Earth 119 (2014): 7175–7194, doi:10.1002/2014JB011270.A large part of global plate motion on mid-ocean ridge transform faults (RTFs) is not accommodated as major earthquakes. When large earthquakes do occur, they often repeat quasiperiodically. We focus here on the high slip rate (∼14 cm/yr) Gofar transform fault on the equatorial East Pacific Rise. This fault is subdivided into patches that slip during Mw 5.5–6 earthquakes every 5 to 6 years. These patches are separated by rupture barriers that accommodate slip through swarms of smaller events and/or aseismic creep. We performed an imaging study to investigate which spatiotemporal variations of the fault zone properties control this segmentation in mechanical behavior and could explain the specific behavior of RTFs at the global scale. We adopt a double-difference approach in a joint inversion of active air gun shots and microseismicity recorded for 1 year. This data set includes the 2008 Mw 6 Gofar earthquake. The along-strike P wave velocity structure reveals an abrupt transition between the barrier area, characterized by a damaged fault zone of 10–20% reduced Vp and a nearly intact fault zone in the asperity area. The importance of the strength of the damage zone on the mechanical behavior is supported by the temporal S wave velocity changes which suggest increased damage within the barrier area, during the week preceding the Mw 6 earthquake. Our results support the conclusion that extended highly damaged zones are the key factor in limiting the role of major earthquakes to accommodate plate motion along RTFs.The material presented here is based on work supported by the National Science Foundation grants 1232725 and 0242117.2015-03-2
    • …
    corecore