349 research outputs found
Transient behaviour of a group of induction motors
The non-linear differential equations describing the
transient behaviour of a group of induction motors are developed
from the equations for a single machine. These equations enable
the behaviour of each machine in the group to be investigated,
either when the complete group is connected to a stiff supply
or when the supply is weak and the machine behaviour is interactive. A numerical solution of the equations using a digital
computer is used to predict the transient currents and torques
of a 0.75 kW/1.5 kW motor group and of a 0.75 kW/1.5 kW/2.25 kW
motor group, and the results obtained are compared with experimentally
obtained results. [Continues.
A new Solar Desalination System Design and Heat Recovery
The work evaluates experimentally technique toimprove fresh water production by careful energy recovery inthe vapour condensation processes; the recovered heat in turnon drives additional evaporation and preheats the feedwater. Apilot plant is designed and constructed in an arid area with 2 m2solar evaporation collector area to evaluate the process. Thisunit is tested on cold and hot days. The effect of mainparameters on fresh water production of the unit is studied. Theexperimental results show that, the production rate andefficiency of the system are strongly affected by solar radiationand level water in solar evaporation collector. Within the studiedranges, the maximum productivity reached to 16.1 kg/ m2day atTvap,av = 87.6 oC , solar radiation 842 W/m2 and level water 1.912kg. According to these results, fresher water production of thepresent system is higher than that solar still desalination systemin the previous studies
Synthesis and characterization of metallic materials for membrane technology
AbstractPowder of metallic materials composed of Fe, Ni was proposed for membrane applications such as microfiltration devices. The powder was synthesized using thermal route of simultaneously sinteringâreduction techniques. The resulting powder has specific porous structure and can be deposited on steel substrate. The formed phases were identified by X-ray phase analysis. The produced powder was characterized by reflected light microscope and scanning electron microscope along with energy-dispersive X-ray spectroscopy (EDX). The reduction behavior of metal oxides was followed up by thermogravimetric techniques. The kinetics data obtained from reduction process were used to elucidate the reduction mechanism under isothermal condition. The microstructure changes accompanying sinteringâreduction processes were investigated under different experimental parameters such as temperature, holding time and gas composition. The results show that pure Fe0.64Ni0.36 with relatively high porosity can be fabricated via reduction route. The presence of NiO plays a significant role in the reduction of iron oxide as well as in the structural changes accompanying the reduction processes. The particle size distribution of the produced metallic materials is being controlled under the different operation conditions to get a homogenous porous metallic structure with well defined porosity. The main advantage of using porous ferroalloy materials is their narrow size distribution leading to a well defined pore size distribution after sintering and reduction
Crude Coal Tar and Ultraviolet (UV) A radiation (Modified Goeckerman Technique) in Treatment of Psoriasis
Background: Psoriasis is a chronic inflammatory dermatosis that has a substantial impact on the quality of life. Goeckerman\u27s technique (GT) has been recruited for the treatment of psoriasis with high clearance rates and long periods of remission.Psoriasis is a chronic inflammatory dermatosis that has a substantial impact on the quality of life. Goeckermanâs technique (GT) has been implemented for the treatment of psoriasis with high clearance rates and long periods of remission. The objective of this article was to evaluate the efficacy and safety of modified GT (crude coal tar 2.5% plus UVA) as an alternative therapeutic modality for psoriatic patients with skin types III-V. Twenty two patients with moderate, severe, and erythrodermic psoriasis were included in this study. All patients received modified GT (crude coal tar 2.5% plus UVA) six days per week for a period of 3 months. Assessment of the rate of reduction of psoriasis area severity index (PASI) was performed, as well as photographic documentation of each patient at baseline and after completion of therapy. There was a significant reduction in PASI scores after therapy in all patients (P=0.001). The rate of PASI reduction after therapy was >50% in 63.6% of patients; 27.3% of patients achieved >75% reduction and 9.1% of patients achieved 26-50% reduction. No serious side effects were reported in any of the patients. Modified GT is a safe and effective therapeutic option for patients with moderate and severe psoriasis.</p
Seroepidemiological Studies on Poultry Salmonellosis and its Public Health Importance
ABSTRACT Non-typhoid Salmonella serovars remain a potential threat to human health, and poultry species are possible sources of these organisms. In this study, trials for Salmonella isolation from poultry and humans were conducted in the period April 2009 through March 2010 in Beni-Suef Governorate, Egypt. Cloacal swabs were collected from different live poultry species including 150 broilers, 50 breeders, 50 layers, 50 turkeys, and 50 ducks, beside 30 litter samples from various poultry farms. Regarding the humans, stool samples as well as hand swabs were collected from 90 workers and poultry contacts of the examined farms. All poultry and human samples were subjected to bacteriological examination and serological identification for Salmonella spp. The recovered Salmonella strains were found belonging to S. Kentucky, S. Typhimurium and S. SaintPaul. The obtained results demonstrated that the occurrence of Salmonella spp. accounted for 16.66, 10.0, 2.0, 6.0 and 2.0% in broilers, breeders, layers, ducks and turkeys respectively. Investigation of litter samples revealed that the occurrence of S. Kentucky was 53.33, 66.66 and 28.57% in broiler's, breeder's and duck's litters respectively. Examination of human samples declared that 8 out of 90 hand swabs were found positive for S. Kentucky whereas all stool samples reacted negatively to all Salmonella spp. In the present study, conclusively Salmonella serovars (S. Kentucky) isolated from chickens were frequently isolated from hand swabs of the examined poultry contacts, this provided evidence that direct contact with poultry or poultry environment may pose health hazards for humans
RESPONSE OF TWO MAIZE CULTIVARS (Zea mays L.) TO ORGANIC MANUR AND MINERAL NANO NITROGEN FERTILIZER UNDER SIWA OASIS CONDITIONS
Two trials were carried out at the Experimental Station farm of Desert Research Center, Teggzerty from Siwa Oasis, Matroh Governorate during the two summer seasons, 2015 and 2016. Trials were performed to study response of two maize hybrids.(Single hybrid 131 and Triple hybrid 329) to organic manure (OM) levels (15 and 30 m3/fed.) and five combinations between mineral and nano nitrogen (N) fertilizers: 1)100% mineral N from the recommended dose (120 kg N/fed.), 2)75% mineral + 25% nano N fertilizers, 3)50% mineral + 50% nano N fertilizers, 4)25% mineral + 75% nano N fertilizers, 5)100% nano N as the recommended rate (500 ppm as foliar application). Mineral N rates were added in three equal doses, with foliar application by nano N rates, after 30, 45 and 60 days from sowing. Treatments, included twenty treatments, was laid out in a splilt-split plot design, with three replicates, OM levels were arranged in the main plots, maize cvs. were allocated in the sub plots, and mineral nano N fertilizer treatments were assigned in the sub-sub plots. At harvest the following characters were recorded, plant height (cm), number of rows/ear, ear length (cm), ear diameter (cm), number of grains/row, 100-grain weight (g), ear weight (ton/fed), grain, straw and biological yields (ton/ fed), shelling (%) and harvest index(%). Results indicated that increasing OM levels significantly increased ear length harvest index and protein content (%), in the 2nd season only, triple hybrid gave the maximum values of all pa rameters, except no. of rows/ear and harvest index, in the 1st season, and 100-grain weight and carbohydrate (%), in both seasons, which had no significant difference with single hybrid in the most cases. Concerning with the effect of mineral and nano N, all parameters, except carbohydrate (%), were increased with increasing mineral N (%) and/or with decreasing nano N (%). Fertilized maize crop by mineral N at 100% or 75% plus 25% nano N fertilizer gave the maximum values of plant ht., no. of rows/ear, ear length and diameter, no. of grains/row, 100-grain wt.,ear weight, grain, straw and biological yields, shelling (%), protein (%), protein yield and harvest index in both seasons. However, fertilized maize crop by nano N at 100% produced the highest value of carbohydrate content (%) in two seasons. Results suggested that selected triple maize hybrid cv. (329), at 30 m3 OM, with 100% mineral N (120 kg N/fed.) or with 75% mineral N (90 kg N/fed.) plus 25% nano N (125 ppm as foliar application) fertilizers could be utilized for attaining the maximal improvement in farmer income by increasing the maize yield under saline conditions at Siwa Oasis, Egypt
Potential gene conversion and source genes for recently integrated Alu elements
Alu elements comprise \u3e10% of the human genome. We have used a computational biology approach to analyze the human genomic DNA sequence databases to determine the impact of gene conversion on the sequence diversity of recently integrated Alu elements and to identify Alu elements that were potentially retroposition competent. We analyzed 269 Alu Ya5 elements and identified 23 members of a new Alu subfamily termed Ya5a2 with an estimated copy number of 35 members, including the de novo Alu insertion in the NFI gene. Our analysis of Alu elements containing one to four (Ya1-Ya4) of the Ya5 subfamily-specific mutations suggests that gene conversion contributed as much as 10%-20% of the variation between recently integrated Alu elements. In addition, analysis of the middle A-rich region of the different Alu Ya5 members indicates a tendency toward expansion of this region and subsequent generation of simple sequence repeats. Mining the databases for putative retroposition-competent elements that share 100% nucleotide identity to the previously reported de novo Alu insertions linked to human diseases resulted in the retrieval of 13 exact matches to the NF1 Alu repeat, three to the Alu element in BRCA2, and one to the Alu element in FGFR2 (Apert syndrome). Transient transfections of the potential source gene for the Apert\u27s Alu with its endogenous flanking genomic sequences demonstrated the transcriptional and presumptive transpositional competency of the element
Development of (4-Phenylamino)quinazoline Alkylthiourea Derivatives as Novel NF-ÎșB Inhibitors
For many inflammatory diseases, new effective drugs with fewer side effects are needed.
While it appears promising to target the activation of the central pro-inflammatory transcription
factor NF-ÎșB, many previously discovered agents suffered from cytotoxicity. In this study, new
alkylthiourea quinazoline derivatives were developed that selectively inhibit the activation of NF-ÎșB
in macrophage-like THPâ1 cells while showing low general cytotoxicity. One of the best com pounds, 19, strongly inhibited the production of IL-6 (IC50 = 0.84 ”M) and, less potently, of TNFα
(IC50 = 4.0 ”M); in comparison, the reference compound, caffeic acid phenethyl ester (CAPE), showed
IC50s of 1.1 and 11.4 ”M, respectively. Interestingly, 19 was found to block the translocation of the
NF-ÎșB dimer to the nucleus, although its release from the IÎșB complex was unaffected. Furthermore,
19 suppressed the phosphorylation of NF-ÎșB-p65 at Ser468 but not at Ser536; however, 19 did not
inhibit any kinase involved in NF-ÎșB activation. The only partial suppression of p65 phosphorylation
might be associated with fewer side effects. Since several compounds selectively induced cell death
in activated macrophage-like THPâ1 cells, they might be particularly effective in various inflam matory diseases that are exacerbated by excess activated macrophages, such as arteriosclerosis and
autoimmune diseases
Evaluation of Combined Use of Temocillin Disk and Mastdisks Inhibitor Combination Set Against Polymerase Chain Reaction for Detection of Carbapenem-Resistant Enterobacteriaceae
AIMS: To evaluate the diagnostic performance of MDI and temocillin disk (30 ĂÂŒg) for detection of carbapenem-resistant Enterobacteriaceae in comparison to real-time PCR.METHODS AND RESULTS: Fifty specimens submitted to the Microbiology Laboratory of Ain Shams University Hospitals and showed resistance to carbapenem drugs through routine culture and susceptibility testing, were assessed by both temocillin disk (30 ĂÂŒg) and MDI set to detect carbapenem-resistant Enterobacteriaceae. Results were compared to real-time PCR for detection of carbapenemase genes blaKPC, blaNDM, blaOXAĂąâŹâ48-like, blaVIM, and blaIMP. Our work revealed that most of the CPE isolates were Klebsiella species (62%) followed by E. coli (24%), Serratia (10%) and Citrobacter (4%). Phenotypic detection of carbapenem-resistant classes revealed OXA - 48 in 96% of isolates, followed by MBLs (82%), and KPC (34%).Ă All isolates were negative for AmpC.Ă Detection of the genes by real-time PCR showed that the predominance was for the blaOXA-48 gene (96%) then blaVIM (94%) followed by blaNDM (54%), blaKPC (46%) and finally blaIMP (40%). Evaluation of the MDI set against PCR showed sensitivity (82.1%) and specificity (70%). The temocillin disk had 97.9% sensitivity and 50% specificity.Ă The evaluation of Temocillin disk and MDI in combination for detection of carbapenem-resistant Enterobacteriaceae showed 99.7% sensitivity and 35% specificity.CONCLUSIONS: Adding Temocillin disk to Mastdisks ID inhibitor combination set provides a simple, easy, rapid and highly sensitive test that can be used for screening and classification of carbapenem-resistant Enterobacteriaceae. However, it still needs confirmation by molecular techniques
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