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Sample records for mekhanizmy radiatsionnoi gibeli

  1. Characterization of the regional variability of flood regimes within the Omo-Gibe River Basin, Ethiopia

    NASA Astrophysics Data System (ADS)

    Yared, Adanech; Demissie, Solomon S.; Sivapalan, Murugesu; Viglione, Alberto; MacAlister, Charlotte

    2014-05-01

    Hydrological variability and seasonality is one of the Ethiopia's primary water resource management challenges. Variability is most obviously manifest in endemic, devastating droughts and floods. While the level of flooding is quite often extremely high and destroys human beings and property, in many cases flooding is of vital importance because the community benefits from flood recession agriculture. This is the case of the lower Omo plain whose agriculture is based on the regularity of the inundations due to flooding of the Omo Gibe River. The big flood in 2006, which caused death for more than 300 people and 2000 cattle, poses a dilemma. Flooding must be controlled and regulated in a way that the damages are reduced as much as possible but the flooding-related benefits are not lost. To this aim, characterization and understanding of hydrological variability of the Omo Gibe River basin is fundamental. The goal of this work is to extract the maximal amount of information on the hydrological variability and specially on the flooding regime from the few data available in the region. Because most of the basin is ungauged, hydrological information is reconstructed using the data from 9 gauged catchments. A daily water balance model has been developed, calibrated and validated for 9 gauged catchments and, subsequently, the parameters have been correlated to catchment characteristics in order to establish a functional relationship that allows to apply the model to ungauged catchments. Daily streamflow has been predicted for 15 ungauged catchments, which are assumed to comprehensively represent the hydrological variability of the Omo-Gibe River Basin. Even though both northern and southern catchments are affected by a strong seasonality of precipitation, with most of the rain falling in less than 3 months, most of the northern catchments are humid, while in the southern part of the Omo-Gibe River basin, the catchments are either humid, dry sub humid, semiarid or arid. As

  2. Mineral deficiency status of ranging zebu (Bos indicus) cattle around the Gilgel Gibe catchment, Ethiopia.

    PubMed

    Dermauw, Veronique; Yisehak, Kechero; Belay, Duguma; Van Hecke, Thomas; Du Laing, Gijs; Duchateau, Luc; Janssens, Geert P J

    2013-06-01

    Mineral deficiencies in cattle, widespread in East Africa, impair optimal health and production and consequently place a great burden on the farmers' income. Therefore, detection of shortages and imbalances of specific minerals is essential. Our objective was to evaluate the mineral status of grazing cattle around the Gilgel Gibe catchment in Ethiopia and associated factors. In study I, individual animal plasma and herd faecal Ca, P, Mg, Na, K, S, Fe, Zn, Mn and Cu concentrations were determined in adult zebu cattle (Bos indicus; n=90) grazing at three altitudes around the catchment, whilst recording body condition score and sex. In study II, liver samples of adult male zebu cattle (n=53) were analysed for Cu, Zn, Fe, Se and Mo concentrations and inspected for parasitic infections. Plasma and liver analyses revealed a Cu deficiency problem in the area, since 68 and 47 % of cattle, respectively, were Cu deprived according to diagnostic criteria for Bos taurus cattle. High hepatic Mo concentrations in 17 % of cases might reflect excessive dietary Mo intake. Liver Se and plasma Na concentrations were too low in 92 and 80 % of cattle. Plasma Mn concentrations were largely below the detection limit. Plasma Cu as well as Ca concentrations were lower in the lowest altitude compared to the highest altitude group (P<0.05), whereas lean to medium cattle had lower plasma Cu concentrations (P<0.05). No differences in hepatic mineral concentrations were detected between cattle with different types of parasitic infection. In conclusion, bovine mineral deficiencies were present in the Gilgel Gibe area and were associated with grazing altitude and body condition score.

  3. Spatio-temporal Hydrological Variability under Changing Climate in the Omo-Gibe River Basin of Ethiopia

    NASA Astrophysics Data System (ADS)

    Shiferaw, E.; Gebremichael, M.; Zagona, E. A.; Hailu, D.; Seyoum, S.

    2012-12-01

    Considering the use of water resource in a sustainable manner and forecasting the future likelihood patterns of this resource under different scenarios can help to mitigate and adapt the multi dimensional impact of climate change. Omo-Gibe River basin is one of the highest socio-economic development sites due to its numerous hydro potential for hydropower and irrigation. However, in recent years, the climate variations induced hydrological variability poses a challenge on decision making for planning and operation of hydropower plants. Hence, there should be a better understanding and projection of all the systems which can lead to a sustainable and optimal use of water for the intended purpose of generating power. The main goal of this study is to synthesize and understand future water resources distribution over space and time, and the extent of climate change induced hydrological variability impact on the generation capacity of the cascade hydropower plants in the Omo-Gibe River basin. An attempt has been made to collate historical and future projected downscaled climate data under different climatic scenarios from different sources. After applying hydrological modelling on the Omo-Gibe River basin with a catchment area of 79,000km2, preliminary result shows there is considerable hydrological variability over space and time which will have consequences on the generation capacity of the cascade hydropower plants across the basin.

  4. Characterizing weathering intensity and trends of geological materials in the Gilgel Gibe catchment, southwestern Ethiopia

    NASA Astrophysics Data System (ADS)

    Regassa, Alemayehu; Van Daele, K.; De Paepe, P.; Dumon, M.; Deckers, J.; Asrat, Asfawossen; Van Ranst, E.

    2014-11-01

    Detailed geological and geochemical characterization is crucial to support soil studies in such geologically and topographically complex systems as the Gilgel Gibe catchment in southwestern Ethiopia. Field studies, as well as mineralogical, petrological and geochemical analyses on selected rock samples and their weathering products revealed that the catchment is dominantly underlain by rhyolites and trachytes, which occur as both lava flows and pyroclastic associations. Most of the lavas have a trachytic texture, while few others are massive or show spherulitic or perlitic texture. The rocks have a SiO2-content ranging from about 62 to 73 wt% (intermediate to felsic composition, on an anhydrous base) and a relatively high Na2O + K2O content ranging from about 9 to 12 wt% (anhydrous base). The dominant phenocrysts present in the rocks are plagioclase, sanidine and Fe-Ti oxide minerals. Alkali-rich amphiboles and quartz occur in most of them, while hornblende, titanite and clinopyroxene are rare. The amount of phenocrysts varies from less than 1 vol.% to about 30 vol.%. The pyroclastic associations are discontinuously scattered within the study area. They all have a glassy matrix (vitrophyric texture) and are composed of a mixture of lithics, crystals and glass. In comparison with the lava samples, the pyroclastic samples exhibit a more variable chemistry. In contrast, the X-ray diffractograms of the pyroclastic deposits and the lavas show little difference. The Chemical Index of Alteration values for the studied samples vary from 53 to 99 indicating moderate to high intensity of weathering. Samples from lava flows have shown less degree of weathering than samples of the pyroclastic associations.

  5. Assessing the potential hydrological impact of the Gibe III Dam on Lake Turkana water level using multi-source satellite data

    NASA Astrophysics Data System (ADS)

    Velpuri, N. M.; Senay, G. B.

    2012-10-01

    Lake Turkana, the largest desert lake in the world, is fed by ungauged or poorly gauged river systems. To meet the demand of electricity in the East African region, Ethiopia is currently building the Gibe III hydroelectric dam on the Omo River, which supplies more than 80% of the inflows to Lake Turkana. On completion, the Gibe III dam will be the tallest dam in Africa with a height of 241 m. However, the nature of interactions and potential impacts of regulated inflows to Lake Turkana are not well understood due to its remote location and unavailability of reliable in situ datasets. In this study, we used 12 yr (1998-2009) of existing multi-source satellite and model-assimilated global weather data. We used a calibrated multi-source satellite data-driven water balance model for Lake Turkana that takes into account model routed runoff, lake/reservoir evapotranspiration, direct rain on lakes/reservoirs and releases from the dam to compute lake water levels. The model evaluates the impact of the Gibe III dam using three different approaches - a historical approach, a rainfall based approach, and a statistical approach to generate rainfall-runoff scenarios. All the approaches provided comparable and consistent results. Model results indicated that the hydrological impact of the Gibe III dam on Lake Turkana would vary with the magnitude and distribution of rainfall post-dam commencement. On average, the reservoir would take up to 8-10 months, after commencement, to reach a minimum operation level of 201 m depth of water. During the dam filling period, the lake level would drop up to 1-2 m (95% confidence) compared to the lake level modeled without the dam. The lake level variability caused by regulated inflows after the dam commissioning were found to be within the natural variability of the lake of 4.8 m. Moreover, modeling results indicated that the hydrological impact of the Gibe III dam would depend on the initial lake level at the time of dam commencement. Areas

  6. Phosphorus contents and phosphorous sorption in soils of the Gilgel Gibe catchment, SW Ethiopia

    NASA Astrophysics Data System (ADS)

    Behn, Christian; Janssen, Manon; Geda Adela, Yalemsew; Lennartz, Bernd

    2013-04-01

    The Gilgel Gibe reservoir, located on the edge of the Ethiopian Plateau, is threatened by siltation and nutrient imports, with phosphate concentrations being more than 50-fold higher than WHO guidelines. Phosphorus reaches the reservoir mainly adsorbed to eroded soil particles. At the same time, P availability for plant production is generally limited in strongly weathered volcanic soils due to their high P sorption capacity. The objectives of this study are therefore to determine the P contents and the P sorption capacity of the soils in the catchment, and to evaluate the influence of slope position and land use. Six catenas surrounding the reservoir (120 to 440 m long), either used as pasture or as arable land, were investigated. Topsoil samples were taken at three slope positions. Parent materials were basalt and rhyolite. Soil texture was clay, the clay content ranged between 41 and 88 %. The soils were moderately to very strongly acid with pH values of 4.6 to 5.9. Plant-available P (double lactate method), total P, Fe and Al (aqua regia digestion) as well as dithionite and oxalate extractable P, Al and Fe contents were determined. Batch experiments were conducted with 7 P concentrations ranging from 0 to 500 mg/l, and the adsorption isotherms will be evaluated using Freundlich and Langmuir models. First results showed that total P contents ranged between 0.2 and 0.5 g/kg soil. Total Fe and Al contents were extremely high with values of 36 to 85 and 29 to 80 g/kg soil, respectively. P contents were significantly correlated with Fe (r=0.68) and clay (r=0.65) contents (P<0.01), which highlights the effect of the parent material. No plant-available P, however, was found in any of the soils, demonstrating the poor growth conditions. P sorption also mainly depended on the soil's Fe content. An influence of slope position or land use on either P content or P sorption capacity could not be detected.

  7. Modeling Lake Turkana Hydrology: Evaluating the potential hydrological impact of Gibe III reservoir on the Lake Turkana water levels using multi-source satellite data

    NASA Astrophysics Data System (ADS)

    Velpuri, N.; Senay, G. B.

    2012-12-01

    Ethiopia is currently building the Gibe III hydroelectric dam on the Omo River, which supplies >80% of the inflows to Lake Turkana, Kenya. On completion, the Gibe III dam will be the tallest dam in Africa (height of 241 m) with a storage capacity of 14.5 billion m3. Arguably, this is one of the most controversial hydro-power projects in the region because the nature of interactions and potential impacts of the dam regulated flows on Lake Turkana are not well understood due to its remote location and unavailability of reliable in situ hydrological datasets. In this research, we used a calibrated multi-source satellite data-driven water balance model for Lake Turkana that takes into account 12 years (1998-2009) of satellite rainfall, model routed runoff, lake/reservoir evapotranspiration, direct rain on lakes/reservoirs and releases from the dam to compute lake water levels. The model was used to evaluate the impact of the Gibe III dam using three different simple but robust approaches - a historical approach; a rainfall based sampling approach; and a non-parametric bootstrap resampling approach to generate rainfall-runoff scenarios. Modelling results indicate that, on average, the reservoir would take up to 8-10 months to reach minimum operation level of 201 m (initial impoundment period). During this period, the dam would regulate the lake inflows up to 50% and as a result the lake level would drop up to 2 m. However, after the initial impoundment period, due to releases from the dam, the rate of lake inflows would be around 10 m3/s less when compared to the rate without Gibe III (650 m3/s). Due to this, the lake levels will decline on average 1.5 m (<1 m to >3 m). Over the entire modeling period including the initial period of impoundment, the average rate of lake inflows due to Gibe III dam was estimated to be 500 m3/s. Results indicated that dam would also moderate the seasonal fluctuations in the lake. Areas along the Lake Turkana shoreline that are vulnerable

  8. Assessing the Potential Hydrological Impact of the Gibe III Dam on Lake Turkana Water Level Using Multi-Source Satellite Data

    USGS Publications Warehouse

    ,; Senai, G.B.

    2012-01-01

    Lake Turkana, the largest desert lake in the world, is fed by ungauged or poorly gauged river systems. To meet the demand of electricity in the East African region, Ethiopia is currently building the Gibe III hydroelectric dam on the Omo River, which supplies more than 80% of the inflows to Lake Turkana. On completion, the Gibe III dam will be the tallest dam in Africa with a height of 241 m. However, the nature of interactions and potential impacts of regulated inflows to Lake Turkana are not well understood due to its remote location and unavailability of reliable in-situ datasets. In this study, we used 12 years (1998–2009) of existing multi-source satellite and model-assimilated global weather data. We use calibrated multi-source satellite data-driven water balance model for Lake Turkana that takes into account model routed runoff, lake/reservoir evapotranspiration, direct rain on lakes/reservoirs and releases from the dam to compute lake water levels. The model evaluates the impact of Gibe III dam using three different approaches such as (a historical approach, a knowledge-based approach, and a nonparametric bootstrap resampling approach) to generate rainfall-runoff scenarios. All the approaches provided comparable and consistent results. Model results indicated that the hydrological impact of the dam on Lake Turkana would vary with the magnitude and distribution of rainfall post-dam commencement. On average, the reservoir would take up to 8–10 months, after commencement, to reach a minimum operation level of 201 m depth of water. During the dam filling period, the lake level would drop up to 2 m (95% confidence) compared to the lake level modelled without the dam. The lake level variability caused by regulated inflows after the dam commissioning were found to be within the natural variability of the lake of 4.8 m. Moreover, modelling results indicated that the hydrological impact of the Gibe III dam would depend on the initial lake level at the time of

  9. Assessing the potential hydrological impact of the Gibe III Dam on Lake Turkana water level using multi-source satellite data

    NASA Astrophysics Data System (ADS)

    Velpuri, N. M.; Senay, G. B.

    2012-03-01

    Lake Turkana, the largest desert lake in the world, is fed by ungauged or poorly gauged river systems. To meet the demand of electricity in the East African region, Ethiopia is currently building the Gibe III hydroelectric dam on the Omo River, which supplies more than 80% of the inflows to Lake Turkana. On completion, the Gibe III dam will be the tallest dam in Africa with a height of 241 m. However, the nature of interactions and potential impacts of regulated inflows to Lake Turkana are not well understood due to its remote location and unavailability of reliable in-situ datasets. In this study, we used 12 years (1998-2009) of existing multi-source satellite and model-assimilated global weather data. We use calibrated multi-source satellite data-driven water balance model for Lake Turkana that takes into account model routed runoff, lake/reservoir evapotranspiration, direct rain on lakes/reservoirs and releases from the dam to compute lake water levels. The model evaluates the impact of Gibe III dam using three different approaches such as (a historical approach, a knowledge-based approach, and a nonparametric bootstrap resampling approach) to generate rainfall-runoff scenarios. All the approaches provided comparable and consistent results. Model results indicated that the hydrological impact of the dam on Lake Turkana would vary with the magnitude and distribution of rainfall post-dam commencement. On average, the reservoir would take up to 8-10 months, after commencement, to reach a minimum operation level of 201 m depth of water. During the dam filling period, the lake level would drop up to 2 m (95% confidence) compared to the lake level modelled without the dam. The lake level variability caused by regulated inflows after the dam commissioning were found to be within the natural variability of the lake of 4.8 m. Moreover, modelling results indicated that the hydrological impact of the Gibe III dam would depend on the initial lake level at the time of dam

  10. Prevalence Soil Transmitted Helminthiasis and malaria co-infection among pregnant women and risk factors in Gilgel Gibe dam Area, Southwest Ethiopia

    PubMed Central

    2013-01-01

    Background Malaria and Soil Transmitted Helminthiasis (STH) are co-endemic and major public health problems in Ethiopia. The aim of the study was to assess the prevalence of malaria and STHs co-infection and to determine the association risk factors. Methods A cross-sectional community based study was conducted on 388 pregnant women living in three districts around Gilgel Gibe Dam area, southwestern Ethiopia. Socio-demographic and socio-economic data, single stool sample and blood sample were collected from each participant. Results The prevalence of STH and malaria was 159 (41%) and 45 (11.6%), respectively and the prevalence of STHs/malaria co-infection was 30 (7.7%). Hookworm was the most prevalent 114 (29.4%) soil transmitted helminthiasis infection followed by Ascaris lumbricoides (A. lumbricoides) 58 (15%) and Trichuris trichiura (T. trichiura) 13 (3.4%). Habit of eating soil (Adjusted Odds Ratio (AOR) = 4.64, 95% CI: 1.50-14.36, P=0.008), presence of stagnant water near study participants’ house (AOR=2.99, 95% CI: 1.28-6.99, P=0.012) and habit of using human feces as a fertilizer (AOR= 5.34, 95% CI: 1.99-14.28, P<0.001) were found to be significantly associated with malaria and STH co-infection among the pregnant women. Hookworm parasitic load was positively correlated with malaria parasitic load (r = 0.299, P<0.001) while A. lumbricoides parasitic load was negatively correlated with malaria parasitic load (r = −0.095, P<0.001). Conclusion Intestinal parasite and/or malaria co-infection is a health problem among pregnant women living around Gilgel Gibe dam area. Therefore, intervention including improving sanitation, removing stagnant water, and health education to the pregnant women should be given. PMID:23837685

  11. Evaluating the Impact of Gilgel Gibe Dam on the Lake Turkana Water Levels: An Illustration from an Endorheic Lake in Africa

    NASA Astrophysics Data System (ADS)

    Velpuri, N.; Senay, G. B.

    2010-12-01

    Lake Turkana is one of the lakes in the Great Rift Valley, Africa. This lake has no outlet hence it is considered as closed or endorheic lake. To meet the demand of electricity in the east African region, Ethiopia is currently building Gilgel Gibe-III dam on the Omo River, which supplies up to 80% of the inflows to the Lake Turkana. On completion, this dam would be the tallest dam in Africa with a height of 241 m. As Lake Turkana is highly dependent on the inflows from the Omo River, the construction of this dam could potentially pose a threat to the downstream river valley and to Lake Turkana. This hydroelectric project is arguably one of the most controversial projects in the region. The impact of the dam on the lake is evaluated using Remote Sensing datasets and hydrologic modeling. First, lake water levels (1998-2007) were estimated using the Simplified Lake Water Balance (SLAB) approach which takes in satellite based rainfall estimates, modeled runoff and evapotranspiration data over the Turkana basin. Modeled lake levels were validated against TOPEX/POSIEDON/Jason-1 satellite altimeter data. Validation results showed that the model could capture observed trends and seasonal variations in lake levels. The fact that the lake is endorheic makes it easy to model the lake levels. Using satellite based estimates for the years 1998-2009, future scenarios for rainfall and evapotranspiration were generated using the Monte Carlo simulation approach and the impact of Gilgel Gibe-III dam on the Lake Turkana water levels is evaluated using SLAB approach. Preliminary results indicate that the impact of the dam on the lake would vary with the initial water level in the lake at the time of dam commissioning. It was found that during the initial period of dam/reservoir filling the lake level would drop up to 2-3 m (95% confidence interval). However, on average the lake would stabilize within 10 years from the date of commissioning. The variability within the lake levels due

  12. The application of predictive modelling for determining bio-environmental factors affecting the distribution of blackflies (Diptera: Simuliidae) in the Gilgel Gibe watershed in Southwest Ethiopia.

    PubMed

    Ambelu, Argaw; Mekonen, Seblework; Koch, Magaly; Addis, Taffere; Boets, Pieter; Everaert, Gert; Goethals, Peter

    2014-01-01

    Blackflies are important macroinvertebrate groups from a public health as well as ecological point of view. Determining the biological and environmental factors favouring or inhibiting the existence of blackflies could facilitate biomonitoring of rivers as well as control of disease vectors. The combined use of different predictive modelling techniques is known to improve identification of presence/absence and abundance of taxa in a given habitat. This approach enables better identification of the suitable habitat conditions or environmental constraints of a given taxon. Simuliidae larvae are important biological indicators as they are abundant in tropical aquatic ecosystems. Some of the blackfly groups are also important disease vectors in poor tropical countries. Our investigations aim to establish a combination of models able to identify the environmental factors and macroinvertebrate organisms that are favourable or inhibiting blackfly larvae existence in aquatic ecosystems. The models developed using macroinvertebrate predictors showed better performance than those based on environmental predictors. The identified environmental and macroinvertebrate parameters can be used to determine the distribution of blackflies, which in turn can help control river blindness in endemic tropical places. Through a combination of modelling techniques, a reliable method has been developed that explains environmental and biological relationships with the target organism, and, thus, can serve as a decision support tool for ecological management strategies.

  13. The Application of Predictive Modelling for Determining Bio-Environmental Factors Affecting the Distribution of Blackflies (Diptera: Simuliidae) in the Gilgel Gibe Watershed in Southwest Ethiopia

    PubMed Central

    Ambelu, Argaw; Mekonen, Seblework; Koch, Magaly; Addis, Taffere; Boets, Pieter; Everaert, Gert; Goethals, Peter

    2014-01-01

    Blackflies are important macroinvertebrate groups from a public health as well as ecological point of view. Determining the biological and environmental factors favouring or inhibiting the existence of blackflies could facilitate biomonitoring of rivers as well as control of disease vectors. The combined use of different predictive modelling techniques is known to improve identification of presence/absence and abundance of taxa in a given habitat. This approach enables better identification of the suitable habitat conditions or environmental constraints of a given taxon. Simuliidae larvae are important biological indicators as they are abundant in tropical aquatic ecosystems. Some of the blackfly groups are also important disease vectors in poor tropical countries. Our investigations aim to establish a combination of models able to identify the environmental factors and macroinvertebrate organisms that are favourable or inhibiting blackfly larvae existence in aquatic ecosystems. The models developed using macroinvertebrate predictors showed better performance than those based on environmental predictors. The identified environmental and macroinvertebrate parameters can be used to determine the distribution of blackflies, which in turn can help control river blindness in endemic tropical places. Through a combination of modelling techniques, a reliable method has been developed that explains environmental and biological relationships with the target organism, and, thus, can serve as a decision support tool for ecological management strategies. PMID:25372843

  14. Birth Preparedness and Its Association with Skilled Birth Attendance and Postpartum Checkups among Mothers in Gibe Wereda, Hadiya Zone, South Ethiopia

    PubMed Central

    Tessema, Fasil; Hailu, Chernet

    2016-01-01

    Background. Birth preparedness program was designed to enhance skilled birth attendance and postpartum checkups of women in a developing country to reduce the three delays that lead women and neonates to death and disability. However, the relationship between birth preparedness with skilled birth attendance and postpartum checkups among mothers is not well studied. Therefore this study is intended to assess the association between birth preparedness and skilled birth attendance and postpartum checkups. Methods. A community based cross-sectional study was conducted from March to April 2014. Eight out of 22 Kebeles were selected using probability proportional to size sampling method. Seven hundred and forty-five mothers were selected randomly from the sampling frame, generated from family folders obtained from health posts. Data was collected using pretested questionnaire by face-to-face interview. Data was entered into EpiData version 3.1 database and analyzed by SPSS version 16. Result. Out of 745 sampled mothers 728 (97.7%) participated in the study. One hundred and twelve (15.4%) and 128 (17.6%) mothers got skilled birth attendance and received postpartum checkups for their last child, respectively. Birth preparedness, educational status of women and their husbands, and antenatal care visits of mothers were found to be predictor of skilled birth attendance and postpartum checkups. Mothers well prepared for child birth were 6.7 times more likely to attend skilled birth attendance [AOR = 6.7 (2.7–16.4)] and 3 times more likely to follow postpartum checkups [AOR = 3.0 (1.5–5.9)] than poorly prepared mothers, respectively. Travel time to reach the nearest health facility was found as predictor for postpartum checkups of mothers; mothers who travel ≤ 2 hours were three times more likely to follow postpartum checkups than mothers who travel > 2 hours (AOR (95% CI) = 3.4 (1.5–7.9)). Conclusion and Recommendation. Skilled birth attendance and postpartum checkups were low. Encouraging women to attend recommended antenatal care visits and providing advice and education on birth preparedness and obstetric danger signs are important interventions to increase skilled birth attendance and postpartum checkups. PMID:28115949

  15. Grazing incidence beam expander

    NASA Astrophysics Data System (ADS)

    Akkapeddi, P. R.; Glenn, P.; Fuschetto, A.; Appert, Q.; Viswanathan, V. K.

    1985-01-01

    A Grazing Incidence Beam Expander (GIBE) telescope is being designed and fabricated to be used as an equivalent end mirror in a long laser resonator cavity. The design requirements for this GIBE flow down from a generic Free Electron Laser (FEL) resonator. The nature of the FEL gain volume (a thin, pencil-like, on-axis region) dictates that the output beam be very small. Such a thin beam with the high power levels characteristic of FELs would have to travel perhaps hundreds of meters or more before expanding enough to allow reflection from cooled mirrors. A GIBE, on the other hand, would allow placing these optics closer to the gain region and thus reduces the cavity lengths substantially. Results are presented relating to optical and mechanical design, alignment sensitivity analysis, radius of curvature analysis, laser cavity stability analysis of a linear stable concentric laser cavity with a GIBE. Fabrication details of the GIBE are also given.

  16. Earthshots: Satellite images of environmental change – Lake Turkana, Kenya and Ethiopia

    USGS Publications Warehouse

    ,

    2013-01-01

    Ethiopia is constructing a series of dams on the Omo River. The Gibe I and Gibe II dams are completed, and the Gibe III dam began filling its reservoir in 2015. Studies are ongoing to understand the interactions between regulated flows as a result of the dams and rainfall on the water levels of Lake Turkana. Scientists use many years’ worth of data to get a better understanding of the lake’s natural variability and how that variability might be affected by dams, irrigation, and rainfall.

  17. The Confederate Command During the Fort Henry-Fort Donelson Campaign, February 1862.

    DTIC Science & Technology

    2007-11-02

    another in theory , regardless if he was a brigadier or full general.6 It was important to clearly establish just what rank a general held as well as...articles were masterpieces of gibes, ridicule, irony, and sarcasm . Buckner made the man appear to be a pompous and arrogant fool at best.8 The...West of the Mississippi in Arkansas, but under Johnston’s command, were 20,000 under Van Dorn. Those forces in theory could be brought east across

  18. Acute effects of ginger extract on biochemical and functional symptoms of delayed onset muscle soreness

    PubMed Central

    Hoseinzadeh, Khadijeh; Daryanoosh, Farhad; Baghdasar, Parvin Javad; Alizadeh, Hamid

    2015-01-01

    Background: Inflammation and pain induced by delayed onset muscle soreness (DOMS) as a result of eccentric exercise (EE) or unaccustomed activity cause some difficulties in exercise for athletes. The purpose of this study was to survey the effect of ginger extract on biochemical and functional symptom of delayed onset muscle soreness. Methods: In a quasi-experimental study, 36 healthy female subjects, who were recruited by intra dormitory calls, randomly divided into 3 groups, including: ginger intake 1 hour before exercise (GIBE), ginger intake immediately after exercise (GIAE) and placebo group (PL). Subjects consumed capsules contain 60 mg of ginger extract (equivalent of 2 g dried ginger powder) or placebo before and after exercise. The exercise protocol consisted of a 20 minute step test using a 46cm step at a rate of 15 steps per minute. The blood samples were taken before, 1, 24 and 48 hour after exercise to assay creatine kinase (CK) and interleukin-6 (IL-6). Muscle pain scores, isometric strength and circumference of thigh muscle, and hip range of motion were recorded at mentioned times. The analysis of variance (ANOVA) with repeated measure was used to determine the differences between groups. Results: The results showed a significant reduction of pain in GIBE compared to GIAE after 24 and 48h of EE and GIAE compared to PL (p<0.05). IL-6 changed significantly in GIBE compared to PL (p<0.05) after 1, 24, and 48h after EE. The other factors didn’t change meaningfully. Conclusion: The finding of this study suggests that 2 grams of ginger may have anti-inflammation and analgesic effect on DOMS. PMID:26793652

  19. The impact of changing climate on the safety of hydropower dams

    NASA Astrophysics Data System (ADS)

    Ayele, Dawit

    2014-05-01

    Global climate change is expected to lead to changes in precipitation patterns and increased frequency and intensity of extreme weather events which may produce conditions outside current design criteria for dams. This study investigated climate change effects on future safety of the Gilgel Gibe II hydro-power dam during extreme floods. The design inflow floods for present and future climate scenarios were calculated using two approaches. Flood frequency analysis was applied to the annual maximum series from the simulated daily flows for present and future periods. Analysis of extreme precipitation and floods was performed using a hydrological model to compute the corresponding extreme flood values for the present situation and future scenarios. The outflow flood with the associated water level was calculated using a reservoir routing model linking all the Gilgel Gibe II reservoirs. Results from this study show that there will be a change in seasonal shift in the peak inflow flood from summer to autumn for the future scenario; and from the range of results of climate models and emission scenarios, the design inflow flood in the autumn is projected to increase for future scenario.

  20. Tuberculosis lymphadenitis in Southwest Ethiopia: a community based cross-sectional study

    PubMed Central

    2012-01-01

    Background In Ethiopia where there is no strong surveillance system and diagnostic facilities are limited, the real burden of tuberculosis (TB) lymphadenitis is not well known. Therefore, we conducted a study to estimate the prevalence of TB lymphadenitis in Southwest Ethiopia. Methods A community based cross-sectional study was conducted from February to March 2009 in the Gilgel Gibe field research area. A total of 30,040 individuals 15 years or older in 10,882 households were screened for TB lymphadenitis. Any individual 15 years or older with lumps in the neck, armpits or groin up on interview were considered TB lymphadenitis suspect. The diagnosis of TB lymphadenitis was established when acid fast bacilli (AFB) smear microscopy of fine needle aspiration (FNA) sample, culture or cytology suggested TB. HIV counseling and testing was offered to all TB lymphadenitis suspects. Descriptive and bivariate analysis was done using SPSS version 15. Results Complete data were available for 27,597 individuals. A total of 87 TB lymphadenitis suspects were identified. Most of the TB lymphadenitis suspects were females (72.4%). Sixteen cases of TB lymphadenitis were confirmed. The prevalence of TB lymphadenitis was thus 58.0 per 100,000 people (16/27,597) (95% CI 35.7-94.2). Individuals who had a contact history with chronic coughers (OR 5.58, 95% CI 1.23-25.43) were more likely to have TB lymphadenitis. Lymph nodes with caseous FNA were more likely to be positive for TB lymphadenitis (OR 5.46, 95% CI 1.69-17.61). Conclusion The prevalence of TB lymphadenitis in Gilgel Gibe is similar with the WHO estimates for Ethiopia. Screening of TB lymphadenitis particularly for family members who have contact with chronic coughers is recommended. Health extension workers could be trained to screen and refer TB lymphadenitis suspects using simple methods. PMID:22770435

  1. Knowledge, Health Seeking Behavior and Perceived Stigma towards Tuberculosis among Tuberculosis Suspects in a Rural Community in Southwest Ethiopia

    PubMed Central

    Abebe, Gemeda; Deribew, Amare; Apers, Ludwig; Woldemichael, Kifle; Shiffa, Jaffer; Tesfaye, Markos; Abdissa, Alemseged; Deribie, Fetene; Jira, Chali; Bezabih, Mesele; Aseffa, Abraham; Duchateau, Luc; Colebunders, Robert

    2010-01-01

    Background Perceived stigma and lack of awareness could contribute to the late presentation and low detection rate of tuberculosis (TB). We conducted a study in rural southwest Ethiopia among TB suspects to assess knowledge about and stigma towards TB and their health seeking behavior. Methods A community based cross sectional survey was conducted from February to March 2009 in the Gilgel Gibe field research area. Any person 15 years and above with cough for at least 2 weeks was considered a TB suspect and included in the study. Data were collected by trained personnel using a pretested structured questionnaire. Logistic regression analysis was done using SPSS 15.0 statistical software. Results Of the 476 pulmonary TB suspects, 395 (83.0%) had ever heard of TB; “evil eye” (50.4%) was the commonly mentioned cause of TB. Individuals who could read and write were more likely to be aware about TB [(crude OR = 2.98, (95%CI: 1.25, 7.08)] and more likely to know that TB is caused by a microorganism [(adjusted OR = 3.16, (95%CI: 1.77, 5.65)] than non-educated individuals. Males were more likely to know the cause of TB [(adjusted OR = 1.92, (95%CI: 1.22, 3.03)] than females. 51.3% of TB suspects perceived that other people would consider them inferior if they had TB. High stigma towards TB was reported by 199(51.2%). 220 (46.2%) did not seek help for their illness. Individuals who had previous anti-TB treatment were more likely to have appropriate health seeking behavior [(adjusted OR = 3.65, (95%CI: 1.89, 7.06)] than those who had not. Conclusion There was little knowledge about TB in the Gilgel Gibe field research area. We observed inappropriate health seeking behavior and stigma towards TB. TB control programs in Ethiopia should educate rural communities, particularly females and non-educated individuals, about the cause and the importance of early diagnosis and treatment of TB. PMID:20948963

  2. Monitoring climate and man-made induced variations in terrestrial water storage (TWS) across Africa using GRACE data

    NASA Astrophysics Data System (ADS)

    Ahmed, M. E.; Sultan, M.; Wahr, J. M.; Yan, E.; Bonin, J. A.; Chouinard, K.

    2012-12-01

    northwest Africa; (5) deforestation in the Congo Basin and southern Tanzania decreased TWS and (6) the construction of dams (e.g., Merowe High Dam, Tekezé, Amerti-Neshi, Beles, Gilgel Gibe I, Gilgel Gibe II, and Karadobi) throughout the GRACE period increased TWS in upstream Nile Valley countries. Given the 10-year monthly GRACE record of water availability data (represented by GRACE TWS) acquired on the sub-basin scale across the globe, and the plans underway for deployment of a GRACE follow-up (2016-2026), consideration should be given to using GRACE TWS data as an alternative, viable drought index, and for monitoring the impacts of human interventions on hydrologic systems.

  3. My Philosophy

    NASA Astrophysics Data System (ADS)

    Lodge, Oliver

    2012-08-01

    Foreword; Part I. An Elementary Survey of Physical Existence: 1. The constitution of things around us; 2. The progress of physical science; 3. Design and purpose in the universe; 4. Religion and science; 5. The organism and the control; 6. The property of inertia; 7. Summary of new knowledge; 8. Machinery of guidance; Part II. Evidence for and Controversies Concerning the Ether: 9. Matter, energy and the ether; 10. The ether and the forms of energy; 11. Faraday's conception of the ether; 12. Modern gibes at the ether; 13. The physical aspect of the universe; 14. Views of Thomas Young, Newton and Fresnel; 15. The ether and relativity; 16. Magnetism and the ether, with suggestions for experiment; 17. Summary of our present knowledge about the ether; Part III. Introduction of Life and Mind: 18. The interaction of the psychical with the physical; 19. Life and mechanism; 20. A psychical function suggested for the ether of space; 21. Ether and the soul; Part IV. The Evidence for Survival and its Mechanism: 22. Evidence for and mechanism of survival; 23. On the difficulty of proving individual survival; 24. On the reasons for the non-recognition of psychical research by the majority of the scientific world; 25. On the apparent element of caprice introduced by the spiritistic hypothesis; 26. The whole organically considered; 27. The spiritistic hypothesis; 28. The bearing of the theory upon religions; Index.

  4. River Water Pollution Status and Water Policy Scenario in Ethiopia: Raising Awareness for Better Implementation in Developing Countries.

    PubMed

    Awoke, Aymere; Beyene, Abebe; Kloos, Helmut; Goethals, Peter L M; Triest, Ludwig

    2016-10-01

    Despite the increasing levels of pollution in many tropical African countries, not much is known about the strength and weaknesses of policy and institutional frameworks to tackle pollution and ecological status of rivers and their impacts on the biota. We investigated the ecological status of four large river basins using physicochemical water quality parameters and bioindicators by collecting samples from forest, agriculture, and urban landscapes of the Nile, Omo-Gibe, Tekeze, and Awash River basins in Ethiopia. We also assessed the water policy scenario to evaluate its appropriateness to prevent and control pollution. To investigate the level of understanding and implementation of regulatory frameworks and policies related to water resources, we reviewed the policy documents and conducted in-depth interviews of the stakeholders. Physicochemical and biological data revealed that there is significant water quality deterioration at the impacted sites (agriculture, coffee processing, and urban landscapes) compared to reference sites (forested landscapes) in all four basins. The analysis of legal, policy, and institutional framework showed a lack of cooperation between stakeholders, lack of knowledge of the policy documents, absence of enforcement strategies, unavailability of appropriate working guidelines, and disconnected institutional setup at the grass root level to implement the set strategies as the major problems. In conclusion, river water pollution is a growing challenge and needs urgent action to implement intersectoral collaboration for water resource management that will eventually lead toward integrated watershed management. Revision of policy and increasing the awareness and participation of implementers are vital to improve ecological quality of rivers.

  5. River Water Pollution Status and Water Policy Scenario in Ethiopia: Raising Awareness for Better Implementation in Developing Countries

    NASA Astrophysics Data System (ADS)

    Awoke, Aymere; Beyene, Abebe; Kloos, Helmut; Goethals, Peter L. M.; Triest, Ludwig

    2016-10-01

    Despite the increasing levels of pollution in many tropical African countries, not much is known about the strength and weaknesses of policy and institutional frameworks to tackle pollution and ecological status of rivers and their impacts on the biota. We investigated the ecological status of four large river basins using physicochemical water quality parameters and bioindicators by collecting samples from forest, agriculture, and urban landscapes of the Nile, Omo-Gibe, Tekeze, and Awash River basins in Ethiopia. We also assessed the water policy scenario to evaluate its appropriateness to prevent and control pollution. To investigate the level of understanding and implementation of regulatory frameworks and policies related to water resources, we reviewed the policy documents and conducted in-depth interviews of the stakeholders. Physicochemical and biological data revealed that there is significant water quality deterioration at the impacted sites (agriculture, coffee processing, and urban landscapes) compared to reference sites (forested landscapes) in all four basins. The analysis of legal, policy, and institutional framework showed a lack of cooperation between stakeholders, lack of knowledge of the policy documents, absence of enforcement strategies, unavailability of appropriate working guidelines, and disconnected institutional setup at the grass root level to implement the set strategies as the major problems. In conclusion, river water pollution is a growing challenge and needs urgent action to implement intersectoral collaboration for water resource management that will eventually lead toward integrated watershed management. Revision of policy and increasing the awareness and participation of implementers are vital to improve ecological quality of rivers.

  6. Occurrence and formation of kaolinite-smectite mixed-layers in 'red and black' soilscapes: a case study from south-western Ethiopia.

    NASA Astrophysics Data System (ADS)

    Dumon, Mathijs; Cornelis, Jean-Thomas; Delvaux, Bruno; Van Ranst, Eric

    2014-05-01

    The relationship between red and black coloured soils in the so-called 'red and black' soilscapes in humid tropical environments has been well documented in the literature. This change in colour is especially striking because it is linked with the landscape position: red soils in the highlands and black soils in the lowlands. The obvious change in colour is also associated with a change in the clay mineralogy: from a mixture composed mostly of iron oxides and kaolinite to one dominated by smectitic minerals. These soilscapes are also more commonly observed in areas where igneous and volcanic rocks occur as parent materials, since these provide the necessary physico-chemical conditions for the formation of smectites. As the parent materials become more intensely leached, the mineralogy becomes dominated by kaolinite and iron oxides, giving rise to the red coloured soils, while smectites either elluviate and accumulate or crystallize directly from the soil solutions in the lower landscape positions. Several accounts have been made of the occurrence of kaolinite-smectite mixed-layer minerals in such red and black soilscapes, even though these mixed-layers are not regarded as a common soil mineral constituent. Often these mixed-layer minerals are considered to be an intermediate product in the mineralogical evolution of these tropical soils. However, the exact processes involved in its formation are still a source of debate. A better understanding and documentation on the conditions under which these mixed-layer minerals are found might improve our understanding. Recent mineralogical analyses of soil profiles located in the Gilgel-Gibe catchment in south-western Ethiopia revealed the clay fraction of 'black' Vertisols and Vertic Planosols to be dominated by kaolinite-smectite mixed-layers. Specific chemical extractions suggest that kaolinite layers are more actively being formed from the soil solution in better-drained topsoil horizons compared to more poorly drained

  7. Thermal Evolution of the Moon and a Possible Explanation for Deep Moonquakes

    NASA Astrophysics Data System (ADS)

    Ziethe, R.; Knapmeyer, M.

    2007-08-01

    The Moonquakes were first detected by the sensitive seismometers placed during the Apollo missions at four relatively densely spaced locations on the lunar surface. Because winds, sea waves, and road traffic do not shake the Moon, the lunar seismometers can detect quite weak Moonquakes even at 1000 km depth. The sheer existence of moonquakes is somewhat surprising, since the Moon is believed to be geologically inactive by today. In contrast to the Earth, were plate motions cause dislocations and build up stresses, which are released through earthquakes, the Moon's interior is significantly less active. However, if no interior processes were going on, no moonquakes could be detected. The physical cause of both deep and shallow moonquakes remains unresolved today because it is difficult to reconcile them with models of the lunar thermal evolution and mantle flows. The monthly and bi-weekle periods in quake frequency hint to a connection to tidal deformation, may be as a cause, or just a trigger. The depth range of 930 to 960 km, which is compatible with most of the deep quakes, should also gibe a hint. We have set up a three dimensional thermal convection model to investigate the thermal evolution of the Moon.We find that the Moons history is dominated by the growth of a massive lithosphere, which constricts the effective transport of heat through convection due to its stiffness. Heat can then only be transported through thermal conduction. Henceforth the lithosphere serves as an insulating shell and keeps the lunar interior relatively warm. Although the hot thermal boundary at the core mantle boundary breaks down after about 0.5 Ga, the Moon's lower mantle is being heated internally due to radioactive heat sources. The convection velocities become smaller with ongoing time, but even today a slight movement in the lower mantle is present. Although the strain rate build up due to convection might not be efficient enough to release moonquakes from the detected