6,468 research outputs found

    Digenetic trematodes from siganid fish Amphacanthus sigan at Macady Bay, Southern Hurghada, Red Sea, Egypt

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    AbstractForty fish samples of Amphacanthus sigan were collected from Sharm El-Naga southern Hurghada to study the parasitic infection included and present a new individual to Helicometra species using light microscope and re-describe another digenean trematode species using scanning electron microscope (SEM). Two trematode species were identified and described; Helicometra siganus n. sp. Nov belonging to Helicometra Odhner, 1902 (family Opecoelidae Ozaki, 1925) which is different from all the listed species in many features as having an elongated body, tapering anteriorly and larger sucker ratio; the vitellaria extended from the intestinal bifurcation to the posterior extremity of the hind-body and finally the cirrus sac and cirrus longer than the other species and extended to the midpoint of esophagus level. So, these criteria are specific and sufficient to consider it as a new species. The other species, Gyliauchen volubilis Nagaty, 1956 (Gyliauchenidae Fuki, 1929 and Ozaki, 1933) which was described before but some other constituent are not evident and appeared using the electron microscope. However, the present sample illustrated transverse striations on the body surface, the acetabulum evaginates outward, ovoid shaped and surrounded by lip-like structures and finally, the excretory pore is situated at some distance from the acetabulum at the posterior end extremity

    Circulating dendritic cells in pediatric patients with nephrotic syndrome

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    Background: Dendritic cells (DCs) represent one of the most extensively studied topics in immunology, because of their central role in the induction and regulation of adaptive immunity, and because of their therapeutic potential for manipulating immune responses. Objectives: To evaluate circulating DC levels in pediatric patients with idiopathic nephrotic syndrome (NS) and its relation to disease activity in these patients. Methods: Fifteen nephrotic patients in relapse (proteinuria>40mg/m2/hour, hypoalbuminemia, and edema) before initiating steroid therapy (Group I), and another15 nephrotic patients in remission after withdrawal of steroid therapy (Group II) were compared to 15 age- and sex- matched healthy children. Besides clinical evaluation and routine laboratory investigations of nephrotic syndrome, circulating DCs were measured by flowcytometry. Results: Circulating DC count was lower in nephrotic patients in both proteinuria and remission groups [(48.89±13.52) and (64.64±7.69) X106/liter respectively] than in the control group (78.54±9.8) X106/liter with highly significant statistical difference (p < 0.001), and lower in proteinuria group than the remission group with highly significant statistical difference (p < 0.001). There was a positive correlation between DC count and serum albumin (moderate association) (p=0.002) and a negative correlation between DC count and urine protein /creatinine ratio (strong association) (p=0.001). Conclusion: Nephrotic syndrome was associated with decreased number of circulating DCs and the decrease was more apparent in patients with active disease. The positive correlation between DC counts and total protein, and serum albumin, and the negative correlation between DC count and urine protein/creatinine ratio point to the link between the decrease in DC count and the severity of the disease process.Keywords: Denderitic cells, nephrotic syndrome, immune deficiencyEgypt J Pediatr Allergy Immunol 2011;9(1):41-4

    The in-vitro Antibiotic Sensitivity Test of Pasteurella multocida Isolated from Layer and Breeder Chickens

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    Abstract The current study aimed to characterize Pasteurella multocida (P. multocida) isolates from layers and breeder chickens in Egypt regarding in-vitro antibiotic sensitivity and resistance pattern. In doing so, spleen, liver, lungs, and heart, were taken aseptically from chickens suffering from a drop in egg production, septicemia, respiratory manifestations, and mortalities between 2016 and 2017. To isolate bacteria, samples were grown on a modified Das medium. Moreover, microscopic appearance and biochemical characteristics were used to identify pure colonies of P. multocida isolates. In the next step, in-vitro antibiotic sensitivity testing was performed on the isolated P. multocida. The findings indicated that P. multocida was found in 36 isolates out of 330 investigated chicken flocks. Small glistering, mucoid, grayish, and dew drop P. multocida colonies were discovered during the culture analysis. Pasteurella multocida isolates were Gram-negative coccobacilli using the microscope. Catalase, indole generation, H2S production, nitrate reduction, and oxidase tests were all positive for the sample; however, methyl red, urease activity, Voge's proskaur, and gelatin liquefaction tests were all negative. They also fermented glucose, mannose, fructose, sucrose, mannitol, xylose, and sorbitol without producing gas but not lactose, arabinose, maltose, inositol, salicin, raffinose, or dulcitol. Isolated P. multocida strains were sensitive to tetracycline, erythromycin, trimethoprim/sulphamethoxazole, norfloxacin, ofloxacin, penicillin, chloramphenicol, and azithromycin, while resistant to ampicillin and clindamycin. Cefoperazone, gentamycin, and streptomycin all showed intermediate sensitivity. https://jwps.rovedar.com/index.php/JWPS/article/view/

    Enhancement of glutamine synthetase activity in Paenibacillus polymyxa by optimization of different growth conditions

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    Biological nitrogen fixation is highly regulated at the transcriptional level by sophisticated regulatory networks that respond to multiple environmental signals. Glutamine synthetase (GS) occupies a central position in cellular metabolism and offer to the cell, a potential point for regulation of biosynthetic function. The aim of this work is to enhance the activity of GS in Paenibacillus polymyxa through altering the constituents of the growth medium, thereby increasing the nitrogen fixation capability. Two bacterial strains were identified as P. polymyxa by 16S rRNA gene (Accession No AB727983). High GS activity was recorded in the two strains, in presence of the divalent cations Mg+2 and Mn+2. Western blot analysis confirmed the presence of the GS at approximately ~60 kDa. GS activity was found to be affected by growth medium, carbon source, nitrogen source and sodium chloride. LB supplemented with 7% glycerol, 0.4% asparagine and 0.15% sodium chloride gave the highest GS activity.Key words: Glutamine, Paenipacillus polymyxa, 16S rRNA, nitrogen fixation, western blot, Mg+2 and Mn+2

    Interferon gamma: is it a co-player in the pathogenesis of idiopathic nephrotic syndrome

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    Introduction: Idiopathic nephrotic syndrome (INS), the most common form of NS in childhood, was considered 4 decades ago as a systemic disorder of T cells, mediated through its released cytokines. To date, the exact incriminated cytokine or immunological mediator is not properly defined. Interferon gamma (IFN-γ), a pro-inflammatory cytokine, is thought to have a role in the provocation of the T cell mediated INS relapse, through promotion of T helper1 (Th1) differentiation and suppression of regulatory T cells (Treg). Aim of the study: to evaluate the immunopathogenic role of IFN-γ in children with steroid sensitive idiopathic nephrotic syndrome (SSNS) through monitoring the changes in its levels with disease course. Methods: This study included twenty-five newly diagnosed children with SSINS. They were all given full dose prednisolone, evaluated at initial diagnosis and at full remission as regards the serum level of IFN-γ. Results: Serum levels of IFN-γ were lowermost at time of diagnosis and increased with remission on corticosteroids. Conclusions: this study points to a role for the lower serum IFN-γ at diagnosis, in the immunopathogenesis of INS than at remission and the rise in its serum level might be a marker of remission induction, however this awaits confirmation in larger scale studies. Studies on renal biopsy specimens are needed to determine the exact renal in situ levels and effects of IFN-

    Complete Study of an Original Power-Exponential Transformation Approach for Generalizing Probability Distributions

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    In this paper, we propose a flexible and general family of distributions based on an original power-exponential transformation approach. We call it the modified generalized-G (MGG) family. The elegance and significance of this family lie in the ability to modify the standard distributions by changing their functional forms without adding new parameters, by compounding two distributions, or by adding one or two shape parameters. The aim of this modification is to provide flexible shapes for the corresponding probability functions. In particular, the distributions of the MGG family can possess increasing, constant, decreasing, “unimodal”, or “bathtub-shaped“ hazard rate functions, which are ideal for fitting several real data sets encountered in applied fields. Some members of the MGG family are proposed for special distributions. Following that, the uniform distribution is chosen as a baseline distribution to yield the modified uniform (MU) distribution with the goal of efficiently modeling measures with bounded values. Some useful key properties of the MU distribution are determined. The estimation of the unknown parameters of the MU model is discussed using seven methods, and then, a simulation study is carried out to explore the performance of the estimates. The flexibility of this model is illustrated by the analysis of two real-life data sets. When compared to fair and well-known competitor models in contemporary literature, better-fitting results are obtained for the new model

    Application of a Novel Synergetic Control for Optimal Power Extraction of a Small-Scale Wind Generation System with Variable Loads and Wind Speeds

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    © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).The synergetic control technique (SCT) has the solution for understanding the symmetry inherent in the non-linear properties of wind turbines (WTs); therefore, they achieve excellent performance and enhance the operation of the WT. Small-scale WTs are efficient and cost-effective; they are usually installed close to where the generated electricity is used. This technology is gaining popularity worldwide for off-grid electricity generation, such as in rural homes, farms, small factories, and commercial properties. To enhance the efficiency of the WT, it is vital to operate the WT at its maximum power. This work proposes an efficient and fast maximum power point tracking (MPPT) technique based on the SCT to eradicate the drawbacks of the conventional methods and enhance the operation of the WT at the MPP regardless of wind speed and load changes. The SCT has advantages, such as robustness, simplified design, fast response, no requirement for knowledge of WT characteristics, no need for wind sensors or intricate power electronics, and straightforward implementation. Furthermore, it improves speed convergence with minimal steady-state oscillations at the MPP. The investigated configuration involves a wind-driven permanent magnet synchronous generator (PMSG), uncontrolled rectifier, boost converter, and variable load. The two converters are used to integrate the PMSG with the load. Three scenarios (step changes in wind speed, stochastic changes in wind speed, and variable electrical load) are studied to assess the SCT. The results prove a high performance of the suggested MPPT control method for a fast convergence speed, boosted WT efficacy, low oscillation levels, and applicability under a variety of environmental situations. This work used the MATLAB/Simulink program and was then implemented on a dSPACE 1104 control board to assess the efficacy of the SCT. Furthermore, experimental validation on a 1 kW Darrieus-type WT driving a PMSG was performed.Peer reviewe

    Effect of FSW Parameters on The Microstructure and Mechanical Properties of T-joints between Dissimilar Al-Alloys

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    The main purpose of this research is to develop T-joints between the aluminum AA 2024-T4 and AA 7075-T6 using friction stir welding.  The effect of tool geometries, tool traveling speed, and rotational rate in the welded T-joints were investigated and discussed. Three different tools were used with different shoulder to pin ratios 3.28, 3.36, and 4.31. After optimization, the best tool dimension has used with the different rotational and welding speeds. Three tool traverse speeds of 50, 75, and 100 mm/min were used. Two rotation rates of 800 rpm and 1000 rpm were applied. After FSW, at a number of the above FSW parameters' combinations, macrostructure and microstructure analyses were done using optical microscopy. In order to have an insight into the mechanical properties, hardness measurements and tensile testing were carried out. Using small shoulder to pin ratio produced visually unacceptable T-joint. Opposite happened by using the tool with 4.31 of shoulder to pin ratio. Furthermore, the results showed sound T-welds with no obvious defects at high rotational rate of 1000 rpm with the two used traveling speeds. Asymmetric temperature distribution was observed between the two sides, advance side (AS) and retreating side (RS
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