Prediction of runoff and discharge in the Simiyu River (tributary of Lake Victoria, Tanzania) using the WetSpa model

International audienceA spatially distributed hydrologic model (WetSpa) is used to estimate daily river water discharge in the Simiyu river a tributary of Lake Victoria, Tanzania. The model combines topography, landuse and soil maps, and observed daily meteorological time series to predict discharge hydrographs and the spatial distribution of hydrological parameters in the catchment. The elevations in the catchment range from 2000 to 1100 m at the outlet, with average slope of 1.4%. The dominant landuse types are, wasteland, grassland, bushland, cultivated land, and a very small area is covered by surface water. The dominant soil types are sandy loam, followed by sandy clay loam, clay loam, clay, loam and sandy clay. There are two distinctive seasons in the Simiyu catchment. Short rains mainly in November, December and January, and long rains in March to May, resulting in a total average annual precipitation of 700 to 1000 mm. The annual potential evapotranspiration is about 1300 mm, and the river discharge at the catchment outlet ranges from 0 to about 200 m3/s. Global parameters of the model are calibrated using three years of daily observed discharge values measured at the mouth of the river at Lake Victoria. The estimated average travel time of the runoff to the outlet of the catchment is about 2.4 d and maximum 8 d for the most remote areas. The model results also show that the surface runoff and interflow provide respectively 38.6% and 61.4% of the total runoff, while the contribution of groundwater drainage is nil. The absence of groundwater drainage is probably due to the high evaporation demand of the atmosphere, which accounts for about 90% of the total precipitation being lost by evapotranspiration. The annual water balance estimated with the model reveals that the total outflow to Lake Victoria is about 500×106 m3 per year, which occurs mainly in the wet seasons, i.e. from March to May and from November to January. The volume of runoff produced by agricultural land amounts to about 9% of the total runoff annually

Simulation of hydrological processes in the Simiyu River, tributary of Lake Victoria, Tanzania

A spatially-distributed hydrologic model (WetSpa) is used to simulate hydrologic processes in the Simiyu River, a tributary of Lake Victoria, Tanzania. The model combines digital maps of topography, land-use and soil texture with observed daily meteorological time series to predict discharge hydrographs and spatial distribution of hydrologic parameters in the basin. The model was calibrated using 3 years of daily observed discharge measured at the mouth of the river at Lake Victoria. The estimated average travel time of the runoff to the outlet of the basin is about 2.4 days and a maximum of 8 days for the most remote areas. The model results show that the surface runoff and interflow provide, respectively, 38.6% and 61.4% of the total discharge, while the contribution of groundwater drainage is about nil. The absence of groundwater drainage is likely due to the high evaporative demand of the atmosphere, which accounts for about 90% of the total precipitation being lost by evapotranspiration. The annual water balance estimated with the model reveals that the total outflow to Lake Victoria is about 475 x 106 m3 per year, which occurs mainly in the wet seasons, i.e. from March to May and from November to January. The discharge volume produced by agricultural land amounts to about 43 x 106 m3 and may carry agrochemicals to Lake Victoria

Blood and tissue biomarker analysis in dogs with osteosarcoma treated with palliative radiation and intra-tumoral autologous natural killer cell transfer.

We have previously reported radiation-induced sensitization of canine osteosarcoma (OSA) to natural killer (NK) therapy, including results from a first-in-dog clinical trial. Here, we report correlative analyses of blood and tissue specimens for signals of immune activation in trial subjects. Among 10 dogs treated with palliative radiotherapy (RT) and intra-tumoral adoptive NK transfer, we performed ELISA on serum cytokines, flow cytometry for immune phenotype of PBMCs, and PCR on tumor tissue for immune-related gene expression. We then queried The Cancer Genome Atlas (TCGA) to evaluate the association of cytotoxic/immune-related gene expression with human sarcoma survival. Updated survival analysis revealed five 6-month survivors, including one dog who lived 17.9 months. Using feeder line co-culture for NK expansion, we observed maximal activation of dog NK cells on day 17-19 post isolation with near 100% expression of granzyme B and NKp46 and high cytotoxic function in the injected NK product. Among dogs on trial, we observed a trend for higher baseline serum IL-6 to predict worse lung metastasis-free and overall survival (P = 0.08). PCR analysis revealed low absolute gene expression of CD3, CD8, and NKG2D in untreated OSA. Among treated dogs, there was marked heterogeneity in the expression of immune-related genes pre- and post-treatment, but increases in CD3 and CD8 gene expression were higher among dogs that lived > 6 months compared to those who did not. Analysis of the TCGA confirmed significant differences in survival among human sarcoma patients with high and low expression of genes associated with greater immune activation and cytotoxicity (CD3e, CD8a, IFN-γ, perforin, and CD122/IL-2 receptor beta). Updated results from a first-in-dog clinical trial of palliative RT and autologous NK cell immunotherapy for OSA illustrate the translational relevance of companion dogs for novel cancer therapies. Similar to human studies, analyses of immune markers from canine serum, PBMCs, and tumor tissue are feasible and provide insight into potential biomarkers of response and resistance

RasGRP4 Is a Novel Ras Activator Isolated from Acute Myeloid Leukemia

Although a number of genetic defects are commonly associated with acute myeloid leukemia (AML), a large percentage of AML cases are cytogenetically normal. This suggests a functional screen for transforming genes is required to identify genetic mutations that are missed by cytogenetic analyses. We utilized a retrovirus-based cDNA expression system to identify transforming genes expressed in cytogenetically normal AML patients. We identified a new member of the Ras guanyl nucleotide-releasing protein (RasGRP) family of Ras guanine nucleotide exchange factors, designating it RasGRP4. Subsequently, cDNA sequences encoding rodent and human RasGRP4 proteins were deposited in GenBank. RasGRP4 contains the same protein domain structure as other members of the RasGRP family, including a Ras exchange motif, a CDC25 homology domain, a C1/diacyglycerol-binding domain, and putative calcium-binding EF hands. We show that expression of RasGRP4 induces anchorage-independent growth of Rat1 fibroblasts. RasGRP4 is a Ras-specific activator and, interestingly, is highly expressed in peripheral blood leukocytes and myeloid cell lines. Unlike other RasGRP proteins, RasGRP4 is not expressed in the brain or in lymphoid cells. We demonstrated that 32D myeloid cells expressing RasGRP4 have elevated levels of activated Ras compared with control cells, and phorbol 12-myristate 13-acetate (PMA) treatment greatly enhanced Ras activation. PMA induced membrane localization of RasGRP4 and 32D cells expressing RasGRP4 were capable of cytokine-independent proliferation in the presence of PMA. We conclude that RasGRP4 is a member of the RasGRP family of Ras guanine nucleotide exchange factors that may play a role in myeloid cell signaling growth regulation pathways that are responsive to diacylglycerol levels

Examination of the role of Mycoplasma bovis in bovine pneumonia and a mathematical model for its evaluation

The authors screened 34 large cattle herds for the presence of Mycoplasma bovis infection by examining slaughtered cattle for macroscopic lung lesions, by culturing M. bovis from lung lesions and at the same time by testing sera for the presence of antibodies against M. bovis. Among the 595 cattle examined, 33.9% had pneumonic lesions, mycoplasmas were isolated from 59.9% of pneumonic lung samples, and 10.9% of sera from those animals contained antibodies to M.bovis. In 25.2% of the cases M. bovis was isolated from lungs with no macroscopic lesions. The proportion of seropositive herds was 64.7%. The average seropositivity rate of individuals was 11.3% but in certain herds it exceeded 50%. A probability model was developed for examining the relationship among the occurrence of pneumonia, the isolation of M. bovis from the lungs and the presence of M. bovis specific antibodies in sera

Team creativity/innovation in culturally diverse teams: A meta‐analysis

This meta-analysis investigates the direction and strength of the relationship between diversity in culturally diverse teams and team creativity/innovation. We distinguish the effects of two diversity levels (i.e., surface- versus deep-level) in culturally diverse teams and examine the moderators suggested by the socio-technical systems framework (i.e., team virtuality and task characteristics in terms of task interdependence, complexity, and intellectiveness). Surface-level diversity in culturally diverse teams is not related to team creativity/innovation, while deep-level diversity in culturally diverse teams is positively related to team creativity/innovation. Moreover, surface-level diversity in culturally diverse teams and team creativity/innovation are negatively related for simple tasks, but unrelated for complex tasks. Deep-level diversity in culturally diverse teams and team creativity/innovation are positively related for collocated teams and interdependent tasks, but unrelated for non-collocated teams and independent tasks. We discuss the theoretical and practical implications

The social relations of health care and household resource allocation in neoliberal Nicaragua

<p>Abstract</p> <p>Background</p> <p>With the transition to neoliberalism, Nicaragua's once-critically acclaimed health care services have substantially diminished. Local level social formations have been under pressure to try to bridge gaps as the state's role in the provision of health care and other vital social services has decreased. This paper presents a case study of how global and national health policies reverberated in the social relations of an extended network of female kin in a rural community during late 2002 - 2003.</p> <p>Methods</p> <p>The qualitative methods used in this ethnographic study included semi-structured interviews completed during bi-weekly visits to 51 households, background interviews with 20 lay and professional health practitioners working in the public and private sectors, and participant-observation conducted in the region's government health centers. Interviews and observational field notes were manually coded and iteratively reviewed to identify and conceptually organize emergent themes. Three households of extended kin were selected from the larger sample to examine as a case study.</p> <p>Results</p> <p>The ongoing erosion of vital services formerly provided by the public sector generated considerable frustration and tension among households, networks of extended kin, and neighbors. As resource allocations for health care seeking and other needs were negotiated within and across households, longstanding ideals of reciprocal exchange persisted, but in conditions of poverty, expectations were often unfulfilled, exposing the tension between the need for social support, versus the increasingly oppositional positioning of social network members as sources of competition for limited resources.</p> <p>Conclusions</p> <p>In compliance with neoliberal structural adjustment policies mandated by multilateral and bilateral agencies, government-provided health care services have been severely restricted in Nicaragua. As the national safety net for health care has been eroded, the viability of local level social formations and their ability to respond to struggles collectively has been put at risk as well. Bi-lateral and multilateral agencies need to take into account local needs and demands, and implement policies in a manner that respects national laws, and protects both the physical and social well-being of individuals.</p

The GTPase RalA Regulates Different Steps of the Secretory Process in Pancreatic β-Cells

BACKGROUND: RalA and RalB are multifuntional GTPases involved in a variety of cellular processes including proliferation, oncogenic transformation and membrane trafficking. Here we investigated the mechanisms leading to activation of Ral proteins in pancreatic beta-cells and analyzed the impact on different steps of the insulin-secretory process. METHODOLOGY/PRINCIPAL FINDINGS: We found that RalA is the predominant isoform expressed in pancreatic islets and insulin-secreting cell lines. Silencing of this GTPase in INS-1E cells by RNA interference led to a decrease in secretagogue-induced insulin release. Real-time measurements by fluorescence resonance energy transfer revealed that RalA activation in response to secretagogues occurs within 3-5 min and reaches a plateau after 10-15 min. The activation of the GTPase is triggered by increases in intracellular Ca2+ and cAMP and is prevented by the L-type voltage-gated Ca2+ channel blocker Nifedipine and by the protein kinase A inhibitor H89. Defective insulin release in cells lacking RalA is associated with a decrease in the secretory granules docked at the plasma membrane detected by Total Internal Reflection Fluorescence microscopy and with a strong impairment in Phospholipase D1 activation in response to secretagogues. RalA was found to be activated by RalGDS and to be severely hampered upon silencing of this GDP/GTP exchange factor. Accordingly, INS-1E cells lacking RalGDS displayed a reduction in hormone secretion induced by secretagogues and in the number of insulin-containing granules docked at the plasma membrane. CONCLUSIONS/SIGNIFICANCE: Taken together, our data indicate that RalA activation elicited by the exchange factor RalGDS in response to a rise in intracellular Ca2+ and cAMP controls hormone release from pancreatic beta-cell by coordinating the execution of different events in the secretory pathway