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  • Author: Sherif Mohamed x
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Sensitivity of some nitrogen fixers and the target pest Fusarium oxysporum to fungicide thiram

This study was carried out to investigate the toxic effects of the fungicide thiram (TMTD) against five nitrogen fixers and the thiram target pest Fusarium oxysporum under laboratory conditions. Nitrogen fixing bacteria Falvobacterium showed the highest values of LD50 and proved to be the most resistant to the fungicide followed by Fusarium oxysporum, while Pseudomonas aurentiaca was the most affected microorganism. LD50 values for these microorganisms were in 2-5 orders of magnitude lower in comparison with LD50 value for Fusarium oxysporum. Thiram was most toxic to Pseudomonas aurentiaca followed by Azospirillum. The lowest toxicity index was recorded for Fusarium oxysporum and Flavobacterium. The slope of the curve for Azomonas, Fusarium oxysporum and Flavobacterium is more steep than that of the other curves, suggesting that even a slight increase of the dose of the fungicide can cause a very strong negative effect. Thiram was more selective to Pseudomonas aurentiaca followed by Azospirillum, Rhizobium meliloti and Azomonas. The lowest selectivity index of the fungicide was recorded for Falvobacterium followed by Fusarium oxysporum. The highest safety coefficient of the fungicide was assigned for Flavobacterium, while Pseudomonas aurentiaca showed the lowest value.

Abstract

Effective stakeholder management (ESM) is a critical success factor for projects. The increasing complexity in the relationships among stakeholders and their diverse characteristics, including power and interests makes the management of stakeholders increasingly challenging. To date, much of the literature has focused on the stakeholder analysis with very limited to the direct and indirect relationships between stakeholder characteristics (SC) and project performance (PP). Therefore, the aim of this study is to fill these research gaps by empirically examining (1) the relationship(s) between SC and PP and (2) the mediation effect of ESM on the above-mentioned relationships. Data analysis was conducted using structural equation modelling. The findings suggest that stakeholder legitimate behaviour (LB), opposing behaviour (OB), and conflicting interests affect the ability to achieve both sets of quantitative and qualitative PP negatively. ESM has been identified as a key element to eliminate the negative effects of the aforementioned behaviours on qualitative (and not quantitative) PP measures.

Abstract

BACKGROUND: Obesity is associated with an increased risk of developing hyperinsulinemia, dyslipidemia, hypertension, premature atherosclerosis, and coronary artery disease in the future.

AIM: This study is designed to assess the relationship between serum adiponectin, asymmetric dimethylarginine (ADMA), and lipid profile among Egyptian overweight and obese children.

METHODS: This cross sectional case control study included 40 selected pre-pubertal overweight and obese children, 24 girls (60%) and 16 boys (40%) aged between 5 to 13 years (8.85 ± 2.7 years), from new cases attending the National nutrition institute clinic during 2013. Forty apparently healthy children of matched age and sex were recruited as a control group.

RESULTS: Obese group showed highly significant higher levels of serum ADMA, triglycerides, and total cholesterol compared with healthy controls (P < 0.000 in all). However, serum adiponectin levels were highly significant lower in obese children compared to healthy controls (P < 0.000). Serum ADMA showed significant positive correlations with height, serum total cholesterol and serum triglycerides levels and significant negative correlation with the body mass index and weight for age z score. Serum adiponectin showed significant negative correlations with BMI, weight, and weight for age z score and significant positive correlation with serum triglycerides. By linear regression analysis; serum adiponectin, and serum triglycerides levels were significant predictors of high serum ADMA level (p =0.045 and 0.015 respectively). BMI, weight, height and serum triglycerides were significant predictors of low serum adiponectin levels (p = 0.005, 0.022, 0.026 and 0.015 respectively).

CONCLUSIONS: Our results revealed that ADMA, Adiponectin and lipid profile can be considered as predictive biomarkers in prediction and prevention of atherosclerotic risk in the future among overweight and obese Egyptian children.

Abstract

Bahr Youssef (B.Y) is a semi-natural branch canal connecting the River Nile with Fayoum depression, in the desert immediately to the west of the Nile Valley, about 92 kilometers southwest of Cairo, for irrigation purposes of El-Minya, El-Fayoum, Bani-Swif, and Giza governorates. The area served by Bahr Youssef reaches about 850.000 feds in the Middle Egypt, out of 1.650.000 feds served by the Ibrahimeya carrier canal, which branches from the River Nile's at Assiut barrage, and extends northward for 55 kilometers, until Dayrut city. In Dayrut; “Ibrahimeya” canal bifurcates into seven carrier canals, (Bahr Youssef is one of them,) through Dayrut Group of regulators. Bahr Youssef suffers from, meandering phenomenon, in many reaches, occurred with all its harmful and destructive effects. As meanders are the direct result of erosion-deposition processes occur in such flatty reaches with hydraulically unstable sections, our effort here is directed for studying the existing geometric, and hydraulic conditions of some representative reaches of Bahr Youssef, to evaluate the size of the problem through intensive field measurements, and to verify the available predicting techniques and theories by comparison with the obtained measured values. Introducing an acceptable, effective and easy method, which can be used for an accurate estimation of the meandering phenomenon, is the main objective of this study. This was achieved through reviewing and assessment of the available predicting techniques, and evaluating their liability, validity, and suitability through the comparison with the field collected measurements.