1,230 research outputs found

    Identifying priority sites for low impact development (LID) in a mixed-use watershed

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    AbstractLow impact development (LID), a comprehensive land use planning and design approach with the goal of mitigating land development impacts to the environment, is increasingly being touted as an effective approach to lessen runoff and pollutant loadings to streams. Broad-scale approaches for siting LID have been developed for agricultural watersheds, but are rare for urban watersheds, largely due to greater land use complexity. Here, we introduce a spatially-explicit approach to assist landscape architects, urban planners, and water managers in identifying priority sites for LID based exclusively on freely available data. We use a large, mixed-use watershed in central Oklahoma, the United States of America, as a case-study to demonstrate our approach. Our results indicate that for one sub-catchment of the Lake Thunderbird Watershed, LID placed in 11 priority locations can facilitate reductions in nutrient and sediment loading to receiving waters by as much as 16% and 17%, respectively. We had a high rate of correctly identified sites (94±5.7%). Our systematic and transferable approach for prioritizing LID sites has the potential to facilitate effective implementation of LID to lessen the effects of urban land use on stream ecosystems

    Ecosystem Services across US Watersheds: A Meta-Analysis of Studies 2000–2014

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    Despite increasing awareness on the importance of rivers in maintaining human wellbeing, there has not been a comprehensive inventory of watershed-scale ecosystem services across the USA. Here, we analyze and summarize the scientific literature within the context of the supply and demand for ecosystem services across 18 major watersheds of the continental US. We reviewed 305 articles and found that 68 provided information on both the biophysical delivery (supply) and the sociocultural and economic values (demand) of ecosystem services. Maintaining populations and habitats, water filtration, and nutrient sequestration/storage were the most extensively assessed services, while educational and aesthetic values were the least frequently studied. Biophysical assessments were the most frequent valuation followed by economic approaches. The majority of the studies were conducted in the eastern US, while the region least studied was the southwest. In addition to identifying the knowledge gaps in watershed-scale ecosystem services, we highlight the need for a common framework for assessing ecosystem services that includes both the assessment of the supply and demand of ecosystem services provided by US watersheds. There is an urgent need to incorporate the role that cultural services and values can play in water resources management and planning in the USA

    Modeling Chronic Traumatic Encephalopathy: The Way Forward for Future Discovery

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    Despite the extensive media coverage associated with the diagnosis of chronic traumatic encephalopathy (CTE), our fundamental understanding of the disease pathophysiology remains in its infancy. Only recently have scientific laboratories and personnel begun to explore CTE pathophysiology through the use of preclinical models of neurotrauma. Some studies have shown the ability to recapitulate some aspects of CTE in rodent models, through the use of various neuropathologic, biochemical, and/or behavioral assays. Many questions related to CTE development however remain unanswered. These include the role of impact severity, the time interval between impacts, the age at which impacts occur, and the total number of impacts sustained. Other important variables such as the location of impacts, character of impacts, and effect of environment/lifestyle and genetics also warrant further study. In this work we attempt to address some of these questions by exploring work previously completed using single and repetitive injury paradigms. Despite some models producing some deficits similar to CTE symptoms, it is clear that further studies are required to understand the development of neuropathological and neurobehavioral features consistent with CTE-like features in rodents. Specifically, acute and chronic studies are needed that characterize the development of tau-based pathology

    Association between opioid agonist therapy use and HIV testing uptake among people who have recently injected drugs:a systematic review and meta-analysis

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    BACKGROUND AND AIM: Globally, nearly one in five people who inject drugs (PWID) are living with HIV, and the rate of new HIV infections in PWID is increasing in some settings. Early diagnosis is crucial for effective HIV control. We reviewed the evidence on the association between opioid agonist therapy (OAT) and HIV testing uptake among PWID. METHODS: We conducted a systematic review searching MEDLINE, Scopus, Web of Science, Cochrane Central Register of Controlled Trials and PsycINFO for studies published from January 2000 to March 2019. Reference lists and conference proceedings were hand-searched. Observational and intervention studies were eligible for inclusion. Risk of bias was assessed using the Risk of Bias in Non-Randomised Studies of Interventions (ROBINS-I) tool. Meta-analyses were conducted using random-effects models. RESULTS: Of 13 373 records identified, 11 studies from Australia, Europe, Malaysia and the United States were included. All studies had at least a serious risk of bias, largely due to confounding and selection bias, making it difficult to draw causal conclusions from the evidence. Ten studies provided data on the association between current OAT use and recent HIV testing. Six showed a positive association, while four provided little evidence of an association: pooled odds ratio (OR) = 1.71, 95% confidence interval (CI) = 1.28-2.27. Looking at having ever been on OAT and having ever been HIV tested, seven studies showed a positive association and three showed either weak or no evidence of an association: pooled OR = 3.82, 95% CI = 2.96-4.95. CONCLUSIONS: Opioid agonist therapy may increase uptake of HIV testing among people who inject drugs, providing further evidence that opioid agonist therapy improves the HIV treatment care cascade

    An enhanced toolkit for the generation of knockout and marker-free fluorescent Plasmodium chabaudi.

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    The rodent parasite Plasmodium chabaudi is an important in vivo model of malaria. The ability to produce chronic infections makes it particularly useful for investigating the development of anti- Plasmodium immunity, as well as features associated with parasite virulence during both the acute and chronic phases of infection. P. chabaudi also undergoes asexual maturation (schizogony) and erythrocyte invasion in culture, so offers an experimentally-amenable in vivo to in vitro model for studying gene function and drug activity during parasite replication. To extend the usefulness of this model, we have further optimised transfection protocols and plasmids for P. chabaudi and generated stable, fluorescent lines that are free from drug-selectable marker genes. These mother-lines show the same infection dynamics as wild-type parasites throughout the lifecycle in mice and mosquitoes; furthermore, their virulence can be increased by serial blood passage and reset by mosquito transmission. We have also adapted the large-insert, linear PlasmoGEM vectors that have revolutionised the scale of experimental genetics in another rodent malaria parasite and used these to generate barcoded P. chabaudi gene-deletion and -tagging vectors for transfection in our fluorescent P. chabaudi mother-lines. This produces a tool-kit of P. chabaudi lines, vectors and transfection approaches that will be of broad utility to the research community

    Microarray patch delivery of un-adjuvanted influenza vaccine induces potent and broad-spectrum immune responses in a phase I clinical trial

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    Microarray patches (MAPs) offer the possibility of improved vaccine thermostability and dose-sparing potential as well as the potential to be safer, more acceptable, easier to use and more cost-effective for the administration of vaccines than injection by needle and syringe. Here, we report a phase I trial (ACTRN12618000112268/ U1111-1207-3550) using the Vaxxas high-density MAP (HD-MAP) to deliver a monovalent influenza vaccine to evaluate the safety, tolerability, and immunogenicity of lower doses of influenza vaccine delivered by MAPs. To the best of our knowledge, this is the first study determining dose reduction potential using MAPs in humans. Monovalent, split inactivated influenza virus vaccine containing A/Singapore/GP1908/ 2015 [H1N1] haemagglutinin (HA) was delivered by MAP into the volar forearm or upper arm, or given intramuscularly (IM) once. Participants (20 per group) received HD-MAPs delivering doses of 15, 10, 5, 2.5 or 0 µg of HA or an IM injection of quadrivalent influenza vaccine (QIV). In two subgroups, skin biopsies were taken on days 1 (pre-vaccination) and 4 for analysis of the cellular composition from the HD-MAP application sites. All laboratory investigators were blind to treatment and participant allocation. The primary objectives of the study were safety and tolerability. Secondary objectives included immunogenicity and dose de-escalation assessments of the influenza vaccine delivered by HD-MAP. Both objectives were assessed for up to 60 days post-vaccination. Please click Download on the upper right corner to see the full abstract

    Abnormal Accumulation of Desmin in Gastrocnemius Myofibers of Patients with Peripheral Artery Disease: Associations with Altered Myofiber Morphology and Density, Mitochondrial Dysfunction and Impaired Limb Function

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    Patients with peripheral artery disease (PAD) develop a myopathy in their ischemic lower extremities, which is characterized by myofiber degeneration, mitochondrial dysfunction and impaired limb function. Desmin, a protein of the cytoskeleton, is central to maintenance of the structure, shape and function of the myofiber and its organelles, especially the mitochondria, and to translation of sarcomere contraction into muscle contraction. In this study, we investigated the hypothesis that disruption of the desmin network occurs in gastrocnemius myofibers of PAD patients and correlates with altered myofiber morphology, mitochondrial dysfunction, and impaired limb function. Using fluorescence microscopy, we evaluated desmin organization and quantified myofiber content in the gastrocnemius of PAD and control patients. Desmin was highly disorganized in PAD but not control muscles and myofiber content was increased significantly in PAD compared to control muscles. By qPCR, we found that desmin gene transcripts were increased in the gastrocnemius of PAD patients as compared with control patients. Increased desmin and desmin gene transcripts in PAD muscles correlated with altered myofiber morphology, decreased mitochondrial respiration, reduced calf muscle strength and decreased walking performance. In conclusion, our studies identified disruption of the desmin system in gastrocnemius myofibers as an index of the myopathy and limitation of muscle function in patients with PAD

    The Peculiar Debris Disk of HD 111520 as Resolved by the Gemini Planet Imager

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    Using the Gemini Planet Imager (GPI), we have resolved the circumstellar debris disk around HD 111520 at a projected range of ~30-100 AU in both total and polarized HH-band intensity. The disk is seen edge-on at a position angle of ~165∘^{\circ} along the spine of emission. A slight inclination or asymmetric warping are covariant and alters the interpretation of the observed disk emission. We employ 3 point spread function (PSF) subtraction methods to reduce the stellar glare and instrumental artifacts to confirm that there is a roughly 2:1 brightness asymmetry between the NW and SE extension. This specific feature makes HD 111520 the most extreme examples of asymmetric debris disks observed in scattered light among similar highly inclined systems, such as HD 15115 and HD 106906. We further identify a tentative localized brightness enhancement and scale height enhancement associated with the disk at ~40 AU away from the star on the SE extension. We also find that the fractional polarization rises from 10 to 40% from 0.5" to 0.8" from the star. The combination of large brightness asymmetry and symmetric polarization fraction leads us to believe that an azimuthal dust density variation is causing the observed asymmetry.Comment: 9 pages, 8 Figures, 1 table, Accepted to Ap
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