Relationships between Runoff, Land Cover and Climate in the Semi-Arid Intermountain Region of the Western U.S.A.

Land cover and climate change with their associated impacts on runoff are among the pressing areas of research within the western United States. In the first paper of this dissertation, we identified a total of 39 watersheds draining to U.S. Geological Survey (USGS) streamflow gauges, chosen either from the USGS Hydroclimatic Climatic Data Network of gauges that are minimally impacted by anthropogenic alterations, or because they have long, relatively continuous streamflow records and are representative of large areas within the study region in Utah. In each of these watersheds we examined trends in precipitation, temperature, snow, streamflow and runoff ratio as well as land use and land cover information. In addition, we developed a water balance model to quantify the sensitivity of runoff to changes in vegetation based on differences in evapotranspiration from different land cover types. The second paper addressed runoff sensitivity to land cover changes in a spatially explicit way by performing detailed simulations using a Regional Hydro Ecological Simulation System (RHESSys) model applied to the Weber River near Oakley watershed (USGS gauge # 10128500). Our runoff sensitivity results suggest that during winter reduced Leaf Area Index (LAI) decreases canopy interception, which tends to increase snow accumulations, and hence snow available for runoff during the early spring melt season. Increased LAI during spring melt season tends to delay the snow melting process due to reduced radiation beneath high LAI surfaces relative to low LAI surfaces. The last paper examined the sensitivity of the Great Salt Lake level to changes in streamflow input or changes in climate that manifest as changes in air temperatures over the lake. We quantified this sensitivity by examining an elasticity measure defined as the ratio of the variability of streamflow, precipitation, evaporation, area and salinity to the variability in historic volume changes. We also developed a mass balance model to simulate lake level and volume driven by stochastic precipitation, streamflow and climate inputs. We showed that fluctuation in streamflow is the dominant factor in lake level fluctuations, but that fluctuations in lake area, which modulates evaporation and precipitation directly on the lake, are also important

An improvement on Nourein's method for the simultaneous determination of the zeroes of a polynomial (An algorithm)

AbstractIn a recent paper [2], Nourein derived an iteration formula, which exhibited cubic convergence for the simultaneous determination of the zeroes of a polynomial. In this paper - following quite a different appraoch - we derive a method which can be viewed as an improvement on that of [2]. The derivation is based on the approximation of the polynomial in question by a Lagrange interpolation formula. We give the algorithm in ALGOL 60. For a given real polynomial, the algorithm caters for the general case of complex zeroes

Watershed Management and Water Production Study for State of Utah

The amount of water produced from a watershed depends on the climate, soils, geology, land cover and land use. Precipitation water inputs in the form of rain or snow are partitioned by the watershed into evapotranspiration, runoff and groundwater recharge. This study has examined factors that may impact the production of runoff from Utah watersheds, focusing on factors related to land and watershed management. Specifically we are interested in how land use changes, such as afforestation, deforestation, agricultural, urban, industrial and mining development, impact runoff. The scale of interest is regional subbasins at the USGS cataloging unit 8 digit Hydrologic Unit Code (HUC) scale (http://water.usgs.gov/GIS/huc.html). Twelve 8 digit HUCs in Utah, with an average area of 4500 km2 were selected for this study. Within these subbasins we identified a total of 39 watersheds draining to USGS streamflow gages, chosen either from the USGS Hydroclimatic Climatic Data Network of gages that are minimally impacted by anthropogenic alterations, or to be representative of large areas within the chosen HUCs with long relatively continuous streamflow records. In each of these watersheds we examined trends in precipitation, temperature, snow, streamflow and runoff ratio. Runoff ratio is the fraction of precipitation that becomes streamflow. We also examined land use and land cover information for these watersheds from the national land cover dataset, southwest regional GAP analyses and the Utah division of water resources water related land use inventory. The most consistent trend noted was in temperature which is increasing. We did not note any significant trends in precipitation. Fourteen of the 39 watersheds examined had significant decreasing trends in streamflow and runoff ratio. We were unable to find definitive causes for these streamflow and runoff ratio trends, though we do have indications that some of them are associated with human development, storage in reservoirs and land cover and land use changes. In analysis of the land cover data we found that unequivocal interpretation of land cover changes was confounded by differences in methodology and technology used to determine land cover over time. We were consequently unable to derive relationships from the data as to how land cover and land use affect water production. So as to provide some information helpful for land management policy making and economic analyses we developed a water balance approach that quantifies sensitivity of runoff production to changes in land cover based on differences in evapotranspiration from different land cover types. The coefficients that quantify the potential evapotranspiration from each land cover type in this analysis are based on our judgment and information from the literature. In coming up with these coefficients we also endeavored to reconcile them with precipitation, streamflow and runoff ratio data for the Utah study watersheds. This water balance approach provides predictions of how water production from these Utah watersheds may change with land cover changes. By considering a range of water balance model parameters we provide water balance derived bounds on how streamflow could change given land cover changes. However, we caution that in the use of these results, the sensitivities depend directly upon the coefficients that quantify the potential evapotranspiration from each land cover type. This represents a fairly gross simplification. In semi-arid settings the vegetation water use is often limited by water availability, rather than potential evapotranspiration, and differences in water yield may relate more to factors such as the timing and rate of water inputs (precipitation intensity and snowmelt). Vegetation also depends strongly on topographic setting, due to factors such as elevation, aspect, and solar radiation exposure. Changes in the proportioning of land cover in a watershed therefore should consider the control that topographic setting has on land cover. Economic considerations associated with changes in water production were also examined. Value was estimated using two approaches: (1) the price for leases and sales of water rights, and (2) using shadow values derived from economic models based on the increasing profitability of water users as water availability increases (or decreases). In general, we noted that irrigated agriculture was responsible for around 80% of water diversions, but that municipal and industrial (M&I) water had higher prices than water for irrigated agriculture. Purchase price for irrigated agriculture in this region has ranged from $25 to$400 per acre foot. Purchase price for M&I water has ranged from $300 to$25,000 per acre foot. Shadow value estimates of the value of water to irrigated agriculture ranged from $300 to$1,500 per acre foot. These figures indicate that, while the value of water is time and place dependent, and it is difficult to generalize about the value of the changes in water production, that in general the economic value of additional water in irrigation is relatively low, but that water for M&I is generally of higher economic value, which suggests that increases in water production from watersheds serving urban areas are likely to have relatively high returns, while water increases used for irrigation use will have relatively low returns

The use of CMIP5 data to simulate climate change impacts on flow regime within the Lake Champlain Basin

Study region: Lake Champlain Basin, northwestern New England, USA. Study focus: Our study uses regional hydrologic analyses and modeling to examine alternative possibilities that might emerge in the Lake Champlain Basin streamflow regime for various climate scenarios. Climate data as well as spatial data were processed to calibrate the Regional Hydro-Ecological Simulation System (RHESSys) model runoff simulations. The 21st century runoff simulations were obtained by driving the RHESSys model with climate data from the Coupled Model Intercomparison Project phase 5 (CMIP5) for representative concentration pathways RCP 4.5 and 8.5. New hydrological insights for the region: Our analyses suggest that most of CMIP5 ensembles fail to capture both the trends and variability observed in historical precipitation when run in hindcast. This raises concerns of using such products in driving hydrologic models for the purpose of obtaining reliable runoff projections that can aid researchers in regional planning. A subset of five climate models among the CMIP5 ensembles have shown statistically significant trends in precipitation, but the magnitude of these trends is not adequately representative of those seen in observed annual precipitation. Adjusted precipitation forecasts project a streamflow regime described by an increase of about 30% in seven-day maximum flow, a four days increase in flooded days, a three orders of magnitude increase in base flow index, and a 60% increase in runoff predictability (Colwell index)

Molecular detection of Mycobacterium tuberculosis and its relationship to histopathological diagnosis in paraffin-embedded lymph node tissues

Background: Tuberculous lymphadenitis (TBL) is one of the most common forms of extra pulmonary tuberculosis (EPTB) worldwide, with difficulty in its diagnosis. And since in the Sudan, the routinely used method for diagnosis is conventional histopathology, the aim of this study was to confirm the histopathological diagnosis by polymerase chain reaction (PCR).Methods: In this study 718 lymph node (LN) biopsies were retrieved, of which 161 were diagnosed as TBL (histopathological evidences). PCR technique was performed for all 161 positive samples to detect the IS6110 sequence of M. tuberculosis as well as to obtain the sensitivity and specificity of morphological diagnosis.Results: Out of 161 specimens 135 (84%) were found to be positive with PCR, the remaining 26 (16%) were negative.Conclusions: Although PCR indicated high sensitivity it can’t be a substitute for conventional histopathology in the diagnosis of tuberculous lymphadenitis in tissue

Hitting Hotspots: Spatial Targeting of Malaria for Control and Elimination

Teun Bousema and colleagues argue that targeting malaria “hotspots” is a highly efficient way to reduce malaria transmission at all levels of transmission intensity

Strategies, Practices, and Challenges for Interagency Co-Authorship in an International Science and Development Program

No abstract availabl

High Mobility and Low Use of Malaria Preventive Measures Among the Jarai Male Youth Along the Cambodia?Vietnam Border

Malaria control along the Vietnam?Cambodia border presents a challenge for both countries\u27 malaria elimination targets as the region is forested, inhabited by ethnic minority populations, and potentially characterized by early and outdoor malaria transmission. A mixed methods study assessed the vulnerability to malaria among the Jarai population living on both sides of the border in the provinces of Ratanakiri (Cambodia) and Gia Lai (Vietnam). A qualitative study generated preliminary hypotheses that were quantified in two surveys, one targeting youth (N = 498) and the other household leaders (N = 449). Jarai male youth, especially in Cambodia, had lower uptake of preventive measures (57.4%) and more often stayed overnight in the deep forest (35.8%) compared with the female youth and the adult population. Among male youth, a high-risk subgroup was identified that regularly slept at friends\u27 homes or outdoors, who had fewer bed nets (32.5%) that were torn more often (77.8%). The vulnerability of Jarai youth to malaria could be attributed to the transitional character of youth itself, implying less fixed sleeping arrangements in nonpermanent spaces or non-bed sites. Additional tools such as long-lasting hammock nets could be suitable as they are in line with current practices

Dimethyl fumarate in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial

Dimethyl fumarate (DMF) inhibits inflammasome-mediated inflammation and has been proposed as a treatment for patients hospitalised with COVID-19. This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing multiple treatments in patients hospitalised for COVID-19 (NCT04381936, ISRCTN50189673). In this assessment of DMF performed at 27 UK hospitals, adults were randomly allocated (1:1) to either usual standard of care alone or usual standard of care plus DMF. The primary outcome was clinical status on day 5 measured on a seven-point ordinal scale. Secondary outcomes were time to sustained improvement in clinical status, time to discharge, day 5 peripheral blood oxygenation, day 5 C-reactive protein, and improvement in day 10 clinical status. Between 2 March 2021 and 18 November 2021, 713 patients were enroled in the DMF evaluation, of whom 356 were randomly allocated to receive usual care plus DMF, and 357 to usual care alone. 95% of patients received corticosteroids as part of routine care. There was no evidence of a beneficial effect of DMF on clinical status at day 5 (common odds ratio of unfavourable outcome 1.12; 95% CI 0.86-1.47; p = 0.40). There was no significant effect of DMF on any secondary outcome

Dimethyl fumarate in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial

Dimethyl fumarate (DMF) inhibits inflammasome-mediated inflammation and has been proposed as a treatment for patients hospitalised with COVID-19. This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing multiple treatments in patients hospitalised for COVID-19 (NCT04381936, ISRCTN50189673). In this assessment of DMF performed at 27 UK hospitals, adults were randomly allocated (1:1) to either usual standard of care alone or usual standard of care plus DMF. The primary outcome was clinical status on day 5 measured on a seven-point ordinal scale. Secondary outcomes were time to sustained improvement in clinical status, time to discharge, day 5 peripheral blood oxygenation, day 5 C-reactive protein, and improvement in day 10 clinical status. Between 2 March 2021 and 18 November 2021, 713 patients were enroled in the DMF evaluation, of whom 356 were randomly allocated to receive usual care plus DMF, and 357 to usual care alone. 95% of patients received corticosteroids as part of routine care. There was no evidence of a beneficial effect of DMF on clinical status at day 5 (common odds ratio of unfavourable outcome 1.12; 95% CI 0.86-1.47; p = 0.40). There was no significant effect of DMF on any secondary outcome