Flash flood simulations for an Egyptian city - mitigation measures and impact of infiltration

Within this work, the impact of mitigation measures and infiltration on flash floods is investigated by using a 2D robust shallow water model including infiltration with the Green-Ampt model. The results show the combined effects of infiltration and mitigation measures as well as the effectiveness of bypass channels in addition to retention basins. Retention basins at appropriate locations could reduce the maximum water depth at critical locations by 23%, while the additional implementation of drainage channels lead to a reduction of 75%, considering also infiltration lead to a further reduction of 97%. If infiltration was considered without mitigation measures, the peak water depth was reduced by 67%. For an exceptional extreme event the measures lead to a reduction of 73% at some locations, while at other locations the overflow from retention basins due to overstraining generated even higher inundations with an increase of 58%

Decomposition of 1,1-Dichloroethane and 1,1-Dichloroethene in an electron beam generated plasma reactor

An electron beam generated plasma reactor is used to decompose low concentrations (100–3000 ppm) of 1,1-dichloroethane and 1,1-dichloroethene in atmospheric pressure air streams. The energy requirements for 90% and 99% decomposition of each compound are reported as a function of inlet concentration. Dichloroethene decomposition is enhanced by a chlorine radical propagated chain reaction. The chain length of the dichloroethene reaction is estimated to increase with dichloroethene concentration from 10 at 100 ppm initial dichloroethene concentration to 30 at 3000 ppm. Both the dichloroethane and dichloroethene reactions seem to be inhibited by electron scavenging decomposition products. A simple analytic expression is proposed for fitting decomposition data where inhibition effects are important and simple first order kinetics are not observed

Plasma Adrenomedullin level in Egyptian children and Adolescents with type 1 diabetes mellitus: relationship to microvascular complications

<p>Abstract</p> <p>Background</p> <p>Adrenomedullin (AM) is known to be elevated in different clinical situations including diabetes mellitus (DM), but its potential role in the pathogenesis of vascular complications in diabetic children and adolescents is to be clarified. Hence, the study aimed at assessment of plasma adrenomedullin levels in children and adolescents with type 1 DM and correlation of these levels with metabolic control and diabetic microvascular complications (MVC).</p> <p>Methods</p> <p>The study was performed in the Diabetes Specialized Clinic, Children's Hospital of Ain Shams University in Cairo, Egypt. It included 55 diabetic children and adolescents (mean age 13.93 ± 3.15 years) who were subdivided into 40 with no MVC and 15 with MVC. Thirty healthy subjects, age-and sex- matched were included as control group (mean age 12.83 ± 2.82 years). Patients and controls were assessed for glycosylated hemoglobin (HbA1c) and plasma adrenomedullin assay using ELISA technique.</p> <p>Results</p> <p>Mean plasma AM levels were significantly increased in patients with and without MVC compared to control group, (110.6 pg/mL, 60.25 pg/mL and 39.2 pg/mL respectively) (P < 0.01) with higher levels in those with MVC (P < 0.05). Plasma AM levels were positively correlated with both duration of diabetes (ρ = 0.703, P < 0.001) and glycemic control (HbA1c) (ρ = 0.453, P < 0.001).</p> <p>Conclusion</p> <p>Higher plasma AM levels in diabetics particularly in those with MVC & its correlation with diabetes duration and metabolic control may reflect the role of AM in diabetic vasculopathy in the pediatric age group.</p

Onboard Plasmatron Hydrogen Production for Improved Vehicles

A plasmatron fuel reformer has been developed for onboard hydrogen generation for vehicular applications. These applications include hydrogen addition to spark-ignition internal combustion engines, NOx trap and diesel particulate filter (DPF) regeneration, and emissions reduction from spark ignition internal combustion engines First, a thermal plasmatron fuel reformer was developed. This plasmatron used an electric arc with relatively high power to reform fuels such as gasoline, diesel and biofuels at an oxygen to carbon ratio close to 1. The draw back of this device was that it has a high electric consumption and limited electrode lifetime due to the high temperature electric arc. A second generation plasmatron fuel reformer was developed. It used a low-current high-voltage electric discharge with a completely new electrode continuation. This design uses two cylindrical electrodes with a rotating discharge that produced low temperature volumetric cold plasma., The lifetime of the electrodes was no longer an issue and the device was tested on several fuels such as gasoline, diesel, and biofuels at different flow rates and different oxygen to carbon ratios. Hydrogen concentration and yields were measured for both the thermal and non-thermal plasmatron reformers for homogeneous (non-catalytic) and catalytic reforming of several fuels. The technology was licensed to an industrial auto part supplier (ArvinMeritor) and is being implemented for some of the applications listed above. The Plasmatron reformer has been successfully tested on a bus for NOx trap regeneration. The successful development of the plasmatron reformer and its implementation in commercial applications including transportation will bring several benefits to the nation. These benefits include the reduction of NOx emissions, improving engine efficiency and reducing the nation's oil consumption. The objective of this program has been to develop attractive applications of plasmatron fuel reformer technology for onboard applications in internal combustion engine vehicles using diesel, gasoline and biofuels. This included the reduction of NOx and particulate matter emissions from diesel engines using plasmatron reformer generated hydrogen-rich gas, conversion of ethanol and bio-oils into hydrogen rich gas, and the development of new concepts for the use of plasmatron fuel reformers for enablement of HCCI engines

Silica Fume Influence on Behavior of Expansive Soil

In this investigation, silica fume (SF) was used as an additive material to study its influence on the characteristics of expansive soil. The soil used in this research was prepared in a lab by mingling bentonite (50 percent by soil dry weight) with natural soil. According to (USCS), the prepared soil was classified as (CH) with a liquid limit of 67.5 percent and a plastic limit of 29.3%. Expansive soil was mixed with different percentages of (SF), (8, 9, 10, 11, 12, and 13%), and experiments were conducted for treated and untreated soil to examine the impact of (SF) on Atterberg's limits, compressibility, swelling, and shear strength parameters. The outcome of this test shows that the use of silica fume raised Atterberg's limits (L.L, P.L, and P.I) and lowered compressibility and swelling percentage, as well as shear strength parameters (c,φ), were altered by increasing the angle of internal friction (φ), and decreased the cohesion (c). From these results, it is concluded that (SF) has a positive effect as an additive material to enhance the geotechnical properties of expansive soil

Metagenomic insight into drought-induced changes in the Egyptian wheat rhizosphere microbiome

Wheat is one of the most important cereal crops and an important source of food for billions of people worldwide. However, drought stress can pose a real threat to its productivity and lead to significant yield losses, especially in Egypt. The rhizospheric microbiome of wheat can play an important role in drought stress and help wheat to respond to this abiotic stress. Understanding this microbiome is therefore also important to improve drought stress resilience and productivity. In this study, a metagenomic analysis was performed to investigate how the composition and diversity of microbial communities associated with the wheat rhizosphere change under drought. Taxonomic and phylogenetic analyses revealed a shift in microbial abundance, with Actinobacteria, Bacteroidetes, Proteobacteria and Verrucomicrobia being the four most abundant phyla of the ethnic microbiota. Remarkably, other classes, including Alphaproteobacteria and Cytophagia, were significantly enriched under drought, which could be a promising enhancement of plant stress altruism. Differential abundance analysis showed that the control samples had higher abundance of microbial taxa such as OD1, WS2, Chlorobi, ABY1 and SHA-109 compared to the drought-treated genotypes. Functional prediction analysis using PICRUSt showed that an uncharacterized ATP-binding protein within the AAA + superfamily is overrepresented under drought conditions. This suggests that these genes may play a role in stress adaptation, possibly via energy-dependent regulation of cellular processes involved in plant survival. Our results expand our understanding of the complexity of responses of the wheat rhizosphere microbiome to drought and have practical implications for the development of microbial target combinations to improve wheat tolerance and productivity in the context of climate change challenges