87 research outputs found
Mosquito population dynamics during the establishment phase of a constructed desert wetland
The Nature Preserve at the Clark County Wetlands Park is a constructed wetland that has the potential to produce new mosquito habitat. This thesis evaluates the potential for the development of a mosquito problem at the newly constructed wetland system by assessing the population dynamics of mosquitoes within the Nature Preserve. Based on data collected from May 2001 through January 2002, I describe fluctuations in mosquito genus and relative abundance during the first summer through winter period of wetland development
Effect of sugarcane residue management on soil organic carbon in a Louisiana agricultural system: implications for carbon sequestration
The soil organic carbon (SOC) pool is an important component of the global carbon budget. Agricultural systems in particular have been identified as an area in which SOC may be increased appreciably when managed for carbon sequestration. In the southern climate region of the United States, potential rates of carbon sequestration in soils are largely unquantified. The aim of this study was to quantify SOC and its spatial variability under two long-term residue management systems, burn and no-burn, for sugarcane (Saccharum Spp. Hyb.). Soil cores to a depth of 1 m were collected using a Giddings probe. Thirty soil cores per treatment were collected along a transect with 1.8-m spacing. Parameters measured were SOC, soil nitrogen, bulk density, gravimetric water content, CEC, and pH. Comparisons between treatments were conducted using paired t-tests. Geostatistical analyses were used to investigate 2-D vertical and lateral spatial trends. In a subsequent sampling, soil cores were collected from depths up to 2.7 m, and SOC, soil nitrogen, and gravimetric water content were measured. Differences in SOC between the two treatments were significant (t = 2.35, p = 0.019) and indicated that the no-burn treatment contained more SOC than the burn treatment. Variogram models indicated that the no-burn treatment (range = 10.19 m) had higher spatial variability than the burn treatment (range = 18.95 m), and kriging illustrated that the burn treatment had a SOC content that was more evenly distributed with depth. Some 70 % of SOC was in the 20-100 cm soil depth, and the greatest differences between the treatments occurred at depths below 60 cm. Estimated carbon sequestration was 0.56 Mg/ha/yr. A major finding from this study is that soil carbon sequestration in the burn and no-burn managements was consistent with other studies in the region; however, significant quantities of SOC may be present at depths below the typical 20-cm sampling depth, and ignoring deeply distributed carbon may result in the underestimation of carbon sequestration
Water and solute transport in the shallow subsurface of a riverine wetland natural levee
In riverine wetlands, the rate and magnitude of water exchanged between river channels and adjacent wetlands have a major influence on hydrologic function and associated aquatic habitat and water quality. River channels are generally separated from backswamps by natural levees; however, preferential flow may allow potentially substantial water and solute exchange between them. Determining the influence of preferential flow on water and solute transport in natural levees requires an innovative approach that allows measurement of transport rates at a scale large enough to capture field-scale variability. To test the hypothesis that preferential flow is important to subsurface water movement through natural levees, we measured hydraulic gradients and solute tracers in a 10 x 9 m grid of 19 shallow (2m) monitoring wells within a large volume (300 m3) of natural levee in the Atchafalaya Basin, Louisiana. In addition to measuring transient responses to natural events, we constructed a small reservoir on the backswamp side of the levee to create a hydraulic gradient from the swamp to the adjacent river channel. We used a simple linear system approach to model residence time distributions of water and solute within the natural levee. Overall, hydraulic response to forcing events, whether from rain or reservoir filling, was rapid in all wells (mean pressure wave velocity 2.5 E-2 m/s) and relatively uniform; in comparison, tracer transport was much slower (mean 3.2 E-4 m/s) and more variable. Spatially, mean subsurface tracer velocities varied over several orders of magnitude: between 1.6 E-7 and 6.8 E-5 m/s under a 12-cm hydraulic gradient and between 2.1 E-7 and 2.2 E-3 m/s under a 70-cm hydraulic gradient. Comparatively greater variability of chemical verses hydraulic behavior indicates multiple functioning transport mechanisms in natural levee sediments and suggests preferential flow; thus, methods that estimate transport rates based on standard point measurements likely greatly underestimate exchange at the field scale. Results suggest that preferential, subsurface flow through natural levees may provide hydrologic connectivity that is meaningful to basin-scale biogeochemical processes
Assessment of Interest in Youth Arts Programming.
Prepared in partnership with the New York Mills Arts Retreat and Regional Cultural Center by the Community Assistantship Program (CAP) administered by the Center for Urban and Regional Affairs, University of Minnesota
New York Mills Regional Cultural Center Youth Arts Program Implementation Project
Prepared in partnership with the New York Mills Arts Retreat and Regional Cultural Center by the Community Assistantship Program (CAP) ,administered by the Center for Urban and Regional Affairs (CURA) at the University of Minnesota
The why, when, and how of computing in biology classrooms [version 1; peer review: 2 approved]
Many biologists are interested in teaching computing skills or using computing in the classroom, despite not being formally trained in these skills themselves. Thus biologists may find themselves researching how to teach these skills, and therefore many individuals are individually attempting to discover resources and methods to do so. Recent years have seen an expansion of new technologies to assist in delivering course content interactively. Educational research provides insights into how learners absorb and process information during interactive learning. In this review, we discuss the value of teaching foundational computing skills to biologists, and strategies and tools to do so. Additionally, we review the literature on teaching practices to support the development of these skills. We pay special attention to meeting the needs of diverse learners, and consider how different ways of delivering course content can be leveraged to provide a more inclusive classroom experience. Our goal is to enable biologists to teach computational skills and use computing in the classroom successfully
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The experience of taking methotrexate for juvenile idiopathic arthritis: results of a cross-sectional survey with children and young people
Background: Children and young people (CYP) with juvenile idiopathic arthritis (JIA) are known to have impaired health-related quality of life (HRQoL), which is improved significantly for many by treatment with methotrexate (MTX). However, a significant proportion of CYP experience difficulties in taking MTX, which may reduce its potential benefits for HRQoL. The aim of this research was to examine how CYP with JIA perceive MTX treatment and how this relates to HRQoL.
Methods: CYP aged 8-16 years taking MTX for JIA completed an adapted Parent Adherence Report Questionnaire, which contains 100mm visual analogue scales, to assess difficulty taking MTX, adherence, frequency of negative reactions and helpfulness of MTX. They also completed the Pediatric Quality of Life Inventory (PedsQL) Generic and Rheumatology scales. We collected data on age, gender, JIA course, disease duration, MTX duration of use, route and dose. Number of inflamed and limited joints were indicators of disease severity.
Results: 116 CYP participated. Most considered MTX helpful (median 87; interquartile range (IQR) 50.75–98) and reported adherence was high (median 98; IQR 90–100). There was greater variability on scores for difficulty (median 22; IQR 2–69) and frequency of negative reactions (median 14.5; IQR 1.25–80). Mean (S.D.) scores on the PedsQL Physical and Psychosocial subscales were 71.63 (24.02) and 71.78 (19.59) respectively, indicating poorer HRQoL than that reported by healthy children. After controlling for demographic and disease variables, poorer physical HRQoL was significantly accounted for by greater difficulty in taking MTX. Poorer psychosocial HRQoL was significantly accounted for by subcutaneous MTX administration, a lower rating of MTX helpfulness and a greater reported difficulty in taking MTX.
Conclusions: Taking MTX for JIA was viewed as helpful by most CYP but HRQoL was poorer in those who reported greater difficulty in taking MTX
Vaginal microbicide and diaphragm use for sexually transmitted infection prevention: A randomized acceptability and feasibility study among high-risk women in Madagascar (Sex Transm Dis (2008) 35(9) 818-26)
In preparation for a randomized controlled trial (RCT), we conducted a pilot RCT of the acceptability and feasibility of diaphragms and candidate vaginal microbicide for sexually transmitted infection prevention among high-risk women in Madagascar
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