Evaluation of the performance of bias-corrected CORDEX regional climate models in reproducing Baro–Akobo basin climate

The applicability of the regional climate model (RCMs) for catchment hydroclimate is obscured due to their systematic bias. As a result, bias correction has become an essential precondition for the study of climate change. This study aimed to evaluate the skill of seven rainfall and five maximum and minimum temperature RCM outputs against observed data in simulating the characteristics of climate at several locations over the Baro–Akobo basin in Ethiopia. The evaluation was performed based on raw and bias-corrected RCMs against observed for a long-term basis. Several statistical metrics were used to compare RCMs against observed using a pixel-to-point approach. In this finding, raw RCMs showed pronounced biases such as lower correlation and higher PBIAS in estimating rainfall and minimum temperature than maximum temperature. However, most RCMs after bias correction showed better performance in reproducing the magnitude and distribution of the mean monthly rainfall and temperature and improve all the statistical metrics. The Mann–Kendall trend test for observed and bias-corrected RCMs indicated a decreasing annual rainfall trend while the maximum and minimum temperature showed an increasing trend in most stations. In most statistical metrics, the ensemble mean resulted in better agreement with observation than individual models in most stations. In general, after bias correction, the ensemble adequately simulates the Baro–Akobo basin climate and can be used for evaluation of future climate projections in the region

Properties of an alkali-thermo stable xylanase from Geobacillus thermodenitrificans A333 and applicability in xylooligosaccharides generation

An extracellular thermo-alkali-stable and cellulase-free xylanase from Geobacillus thermodenitrificans A333 was purified to homogeneity by ion exchange and size exclusion chromatography. Its molecular mass was 44 kDa as estimated in native and denaturing conditions by gel filtration and SDS-PAGE analysis, respectively. The xylanase (GtXyn) exhibited maximum activity at 70 °C and pH 7.5. It was stable over broad ranges of temperature and pH retaining 88 % of activity at 60 °C and up to 97 % in the pH range 7.5–10.0 after 24 h. Moreover, the enzyme was active up to 3.0 M sodium chloride concentration, exhibiting at that value 70 % residual activity after 1 h. The presence of other metal ions did not affect the activity with the sole exceptions of K+ that showed a stimulating effect, and Fe2+, Co2+ and Hg2+, which inhibited the enzyme. The xylanase was activated by non-ionic surfactants and was stable in organic solvents remaining fully active over 24 h of incubation in 40 % ethanol at 25 °C. Furthermore, the enzyme was resistant to most of the neutral and alkaline proteases tested. The enzyme was active only on xylan, showing no marked preference towards xylans from different origins. The hydrolysis of beechwood xylan and agriculture-based biomass materials yielded xylooligosaccharides with a polymerization degree ranging from 2 to 6 units and xylobiose and xylotriose as main products. These properties indicate G. thermodenitrificans A333 xylanase as a promising candidate for several biotechnological applications, such as xylooligosaccharides preparation

Informational entropy : a failure tolerance and reliability surrogate for water distribution networks

Evolutionary algorithms are used widely in optimization studies on water distribution networks. The optimization algorithms use simulation models that analyse the networks under various operating conditions. The solution process typically involves cost minimization along with reliability constraints that ensure reasonably satisfactory performance under abnormal operating conditions also. Flow entropy has been employed previously as a surrogate reliability measure. While a body of work exists for a single operating condition under steady state conditions, the effectiveness of flow entropy for systems with multiple operating conditions has received very little attention. This paper describes a multi-objective genetic algorithm that maximizes the flow entropy under multiple operating conditions for any given network. The new methodology proposed is consistent with the maximum entropy formalism that requires active consideration of all the relevant information. Furthermore, an alternative but equivalent flow entropy model that emphasizes the relative uniformity of the nodal demands is described. The flow entropy of water distribution networks under multiple operating conditions is discussed with reference to the joint entropy of multiple probability spaces, which provides the theoretical foundation for the optimization methodology proposed. Besides the rationale, results are included that show that the most robust or failure-tolerant solutions are achieved by maximizing the sum of the entropies

A comparison of polarized and non-polarized human endometrial monolayer culture systems on murine embryo development

BACKGROUND: Co-culture of embryos with various somatic cells has been suggested as a promising approach to improve embryo development. Despite numerous reports regarding the beneficial effects of epithelial cells from the female genital tract on embryo development in a co-culture system, little is known about the effect of these cells when being cultured under a polarized condition on embryo growth. Our study evaluated the effects of in vitro polarized cells on pre-embryo development. METHODS: Human endometrial tissue was obtained from uterine specimens excised at total hysterectomy performed for benign indications. Epithelial cells were promptly isolated and cultured either on extra-cellular matrix gel (ECM-Gel) coated millipore filter inserts (polarized) or plastic surfaces (non-polarized). The epithelial nature of the cells cultured on plastic was confirmed through immunohistochemistry, and polarization of cells cultured on ECM-Gel was evaluated by transmission electron microscopy (TEM). One or two-cell stage embryos of a superovulated NMRI mouse were then flushed and placed in culture with either polarized or non-polarized cells and medium alone. Development rates were determined for all embryos daily and statistically compared. At the end of the cultivation period, trophectoderm (TE) and inner cell mass (ICM) of expanded blastocysts from each group were examined microscopically. RESULTS: Endometrial epithelial cells cultured on ECM-Gel had a highly polarized columnar shape as opposed to the flattened shape of the cells cultured on a plastic surface. The two-cell embryos cultured on a polarized monolayer had a higher developmental rate than those from the non-polarized cells. There was no statistically significant difference; still, the blastocysts from the polarized monolayer, in comparison with the non-polarized group, had a significantly higher mean cell number. The development of one-cell embryos in the polarized and non-polarized groups showed no statistically significant difference. CONCLUSION: Polarized cells could improve in vitro embryo development from the two-cell stage more in terms of quality (increasing blastocyst cellularity) than in terms of developmental rate

Error propagation of climate model rainfall to streamflow simulation in the Gidabo sub-basin, Ethiopian Rift Valley Lakes Basin

This study assesses bias error of rainfall from climate models and related error propagation effects to simulated streamflow in the Gidabo sub-basin, Ethiopia. Rainfall is obtained from a combination of four global and regional climate models (GCM-RCMs), and streamflow is simulated by means of the Hydrologiska Byråns Vattenbalansavdelning (HBV-96) rainfall-runoff model. Five bias correction methods were tested to reduce the rainfall bias. To assess the effects of rainfall bias error propagation, percent bias (PBIAS), difference in coefficient of variation (CV), and 10th and 90th percentile indicators were applied. Findings indicate that the bias of the uncorrected rainfall caused large errors in simulated streamflow. All five bias correction methods improved the HBV-96 model performance in terms of capturing the observed streamflow. Overall, the findings of this study indicate that the magnitude of the error propagation varies subject to the selected performance indicator, bias correction method and climate model

Biochemical and immunological properties of related small ruminant trophoblast interferons

The objectives of this study were 1) to evaluate the biochemical and immunological properties of caprine interferon tau (cIFNγ), 2) to determine if intrauterine injection of recombinant ovine interferon tau (roIFNγ) extends CL life span in goats, and 3) to evaluate potential side effects of intramuscular (im) administration roIFNγ. Caprine IFNγ was purified, and its effects on lymphocyte proliferation were evaluated. Incorporation of 3H- thymidine into newly synthesized DNA was suppressed (P\u3c0.05) by clFNγ. Spanish goats were also fitted with bilateral uterine catheters at Day 7 or 8 postestrus. The goats received twice-daily intrauterine injections of 100 μg roIFNγ (n = 4) or caprine serum proteins (n = 4) from Days 14 to 18 postestrus. Intrauterine injection of roIFNγ extended CL life span compared with that of control goats (26.4 ± 1.7 vs 17.8 ± 1.9 d, respectively; P\u3c0.01). Potential side effects of intramuscular injections of roIFNγ were also evaluated. Goats received 0, 1, 2 or 4 mg of roIFNγ on Days 10, 13, 16 or 19 of the estrous cycle. Treatment of goats with roIFN resulted in hyperthermia (P\u3c0.01), with rectal temperatures of 40.5δ C recorded after 4 h and returning to normal (38.5δ C) after 24 h. Concomitant with the increase in rectal temperatures was a decrease (P\u3c0.01) in plasma progesterone concentrations. Therefore, the tau interferons of goats and sheep have similar biological properties and roIFNγ has side effects associated with other classes of interferons

Complexes of lutein with bovine and caprine caseins and their impact on lutein chemical stability in emulsion systems: Effect of arabinogalactan

Lutein is an important xanthophyll carotenoid with many benefits to human health. Factors affecting the application of lutein as a functional ingredient in low-fat dairy-like beverages (pH 6.0–7.0) are not well understood. The interactions of bovine and caprine caseins with hydrophobic lutein were studied using UV/visible spectroscopy as well as fluorescence. Our studies confirmed that the aqueous solubility of lutein is improved after binding with bovine and caprine caseins. The rates of lutein solubilization by the binding to bovine and caprine caseins were as follows: caprine αS1-II-casein 34%, caprine αS1-I-casein 10%, and bovine casein 7% at 100 μM lutein. Fluorescence of the protein was quenched on binding supporting complex formation. The fluorescence experiments showed that the binding involves tryptophan residues and some nonspecific interactions. Scatchard plots of lutein binding to the caseins demonstrated competitive binding between the caseins and their sites of interaction with lutein. Competition experiments suggest that caprine αS1-II casein will bind a larger number of lutein molecules with higher affinity than other caseins. The chemical stability of lutein was largely dependent on casein type and significant increases occurred in the chemical stability of lutein with the following pattern: caprine αS1-II-casein \u3e caprine αS1-I-casein \u3e bovine casein. Addition of arabinogalactan to lutein-enriched emulsions increases the chemical stability of lutein-casein complexes during storage under accelerated photo-oxidation conditions at 25°C. Therefore, caprine αS1-II-casein alone and in combination with arabinogalactan can have important applications in the beverage industry as carrier of this xanthophyll carotenoid (lutein)