641 research outputs found

    Thermal conductivity vs depth profiling using the hot disk technique-Analysis of anisotropic, inhomogeneous structures

    Get PDF
    A recently developed method for analyzing the thermal conductivity vs depth variation near a sample surface has been extended to include inhomogeneous samples with anisotropy. If not considered, the anisotropy ratio in the sample structure can distort the depth-position data of the original test method. The anisotropy ratio is introduced in the original computational scheme in order to improve the depth-position estimations for inhomogeneous structures with anisotropy. The proposed approach has been tested in experiments and shown to improve depth position mapping

    Programmatic correlates of maternal healthcare seeking behaviors in Ethiopia

    Get PDF
    Background: Considerable improvement in maternal healthcare use has been observed since the inception of the health extension program (HEP) in Ethiopia in 2003.Objective: This paper evaluates the influence of HEP outreach strategies on maternal healthcare use.Method: Cross-sectional survey of 2,916 women with children 0 to 11 months from Amhara, Oromiya, Southern Nations, Nationalities and People’s, and Tigray regions, obtained between December 2008 and January 2009, were analyzed using regression models to assess the impacts of HEP strategies on maternal health outcomes.Result: The analyses found that communities (i.e., kebeles) with relatively high prevalence of model families, higher rate of household visits by health extension workers, and higher rate of household visits by voluntary community health workers were associated with improved antenatal care use, tetanus toxoid vaccination coverage, and receiving postnatal care visits; but the strategies were not associated with deliveries attended by health professionals.Conclusion: Although the impacts of HEP strategies on maternal healthcare use were statistically significant, they were not optimum to reach the maternal mortality reduction targets of the government of Ethiopia. The HEP needs to review and strengthen its community based strategies in order to reach its goals. [Ethiop. J. Health Dev. 2010;24 Special Issue 1:92-99

    Calibrating spectral estimation for the LISA Technology Package with multichannel synthetic noise generation

    Full text link
    The scientific objectives of the Lisa Technology Package (LTP) experiment, on board of the LISA Pathfinder mission, demand for an accurate calibration and validation of the data analysis tools in advance of the mission launch. The levels of confidence required on the mission outcomes can be reached only with an intense activity on synthetically generated data. A flexible procedure allowing the generation of cross-correlated stationary noise time series was set-up. Multi-channel time series with the desired cross correlation behavior can be generated once a model for a multichannel cross-spectral matrix is provided. The core of the procedure is the synthesis of a noise coloring multichannel filter through a frequency-by-frequency eigendecomposition of the model cross-spectral matrix and a Z-domain fit. The common problem of initial transients in noise time series is solved with a proper initialization of the filter recursive equations. The noise generator performances were tested in a two dimensional case study of the LTP dynamics along the two principal channels of the sensing interferometer.Comment: Accepted for publication in Physical Review D (http://prd.aps.org/

    Global Monthly Water Scarcity: Blue Water Footprints versus Blue Water Availability

    Get PDF
    Freshwater scarcity is a growing concern, placing considerable importance on the accuracy of indicators used to characterize and map water scarcity worldwide. We improve upon past efforts by using estimates of blue water footprints (consumptive use of ground- and surface water flows) rather than water withdrawals, accounting for the flows needed to sustain critical ecological functions and by considering monthly rather than annual values. We analyzed 405 river basins for the period 1996–2005. In 201 basins with 2.67 billion inhabitants there was severe water scarcity during at least one month of the year. The ecological and economic consequences of increasing degrees of water scarcity – as evidenced by the Rio Grande (Rio Bravo), Indus, and Murray-Darling River Basins – can include complete desiccation during dry seasons, decimation of aquatic biodiversity, and substantial economic disruption

    Quantification of Methane Emissions from Indoor-Fed Fogera Dairy Cows Using Laser Methane Detector

    Get PDF
    Portable laser methane detectors (LMDs) may be an economical means of estimating CH4 emissions from ruminants. Here, we validated an LMD-based approach and then used that approach to evaluate CH4 emissions from indigenous dairy cows in a dryland area of Ethiopia. First, we validated our LMD-based approach in Simmental crossbred beef cattle (n = 2) housed in respiration chambers and fed either a high- or low-concentrate diet. We found that the exhaled air CH4 concentrations measured by LMD were linearly correlated with the CH4 emissions determined by infrared-absorption-based gas analyzer (r2 = 0.55). On the basis of these findings, we constructed an estimation equation to determine CH4 emissions (y, mg min−1) from LMD CH4 concentrations (x, ppm m) as y = 0.4259x + 38.61. Next, we used our validated LMD approach to examine CH4 emissions in Fogera dairy cows grazed for 8 h d−1 (GG, n = 4), fed indoors on natural-grassland hay (CG1, n = 4), or fed indoors on Napier-grass (Pennisetum purpureum) hay (CG2, n = 4). All the cows were supplemented with concentrate feed. Daily CH4 emissions did not differ among the three groups; however, a numerically greater milk yield was obtained from the CG2 cows than from the GG cows, suggesting that Napier-grass hay might be better than natural-grassland hay for indoor feeding. The CG1 cows had higher CH4 emissions per feed intake than the other groups, without significant increases in milk yield and body-weight gain, suggesting that natural-grassland hay cannot be recommended for indoor-fed cows. These findings demonstrate the potential of using LMDs to rapidly and economically evaluate feeding regimens for dairy cows in areas under financial constraint, while taking CH4 emissions into consideration

    Reduction of seafood processing wastewater using technologies enhanced by swim–bed technology

    Get PDF
    The increasing growth of the seafood processing industries considerably requires more industrial process activities and water consumption. It is estimated that approximately 10–40 m3 of wastewater is generated from those industries for processing one-tonne of raw materials. Due to limitations and regulations in natural resources utilization, a suitable and systematic wastewater treatment plant is very important to meet rigorous discharge standards. As a result of food waste biodegradability, the biological treatment and some extent of swim-bed technology, including a novel acryl-fibre (biofilm) material might be used effectively to meet the effluent discharge criteria. This chapter aims to develop understanding on current problems and production of the seafood wastewater regarding treatment efficiency and methods of treatment

    Groundwater depletion embedded in international food trade

    Get PDF
    Recent hydrological modelling1 and Earth observations2,3 have located and quantified alarming rates of groundwater depletion worldwide. This depletion is primarily due to water withdrawals for irrigation1,2,4, but its connection with the main driver of irrigation, global food consumption, has not yet been explored. Here we show that approximately eleven per cent of non-renewable groundwater use for irrigation is embedded in international food trade, of which two-thirds are exported by Pakistan, the USA and India alone. Our quantification of groundwater depletion embedded in the world’s food trade is based on a combination of global, cropspecific estimates of non-renewable groundwater abstraction and international food trade data. A vast majority of the world’s population lives in countries sourcing nearly all their staple crop imports from partners who deplete groundwater to produce these crops, highlighting risks for global food and water security. Some countries, such as the USA, Mexico, Iran and China, are particularly exposed to these risks because they both produce and import food irrigated from rapidly depleting aquifers. Our results could help to improve the sustainability of global food production and groundwater resource management by identifying priority regions and agricultural products at risk as well as the end consumers of these products
    corecore