195 research outputs found

    Studying the Dynamical Properties of 20 Nearby Galaxy Clusters

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    Using SDSS-DR7, we construct a sample of 42382 galaxies with redshifts in the region of 20 galaxy clusters. Using two successive iterative methods, the adaptive kernel method and the spherical infall model, we obtained 3396 galaxies as members belonging to the studied sample. The 2D projected map for the distribution of the clusters members is introduced using the 2D adaptive kernel method to get the clusters centers. The cumulative surface number density profile for each cluster is fitted well with the generalized King model. The core radii of the clusters' sample are found to vary from 0.18 Mpc \mbox{h}^{-1} (A1459) to 0.47 Mpc \mbox{h}^{-1} (A2670) with mean value of 0.295 Mpc \mbox{h}^{-1}. The infall velocity profile is determined using two different models, Yahil approximation and Praton model. Yahil approximation is matched with the distribution of galaxies only in the outskirts (infall regions) of many clusters of the sample, while it is not matched with the distribution within the inner core of the clusters. Both Yahil approximation and Praton model are matched together in the infall region for about 9 clusters in the sample but they are completely unmatched for the clusters characterized by high central density. For these cluster, Yahil approximation is not matched with the distribution of galaxies, while Praton model can describe well the infall pattern of such clusters.Comment: 16 pages, 8 figure

    Numerical investigations on the performance and emissions of a turbocharged engine using an ethanol-gasoline blend

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    Due to a scarcity of fossil fuel supplies and concerns about pollution, the use of ethanol in gasoline has become a priority in the automobile industry. This paper aims to investigate the effect of different ethanol-gasoline fuel blend ratios, namely E20 (% ethanol + % gasoline), E50 (% ethanol + % gasoline), and E75 (75% ethanol + 25% gasoline) on a 1.6 L turbocharged, 4-cylinder, 2017 Proton Preve Premium CFE CVT engine, where E0 (pure gasoline) is taken as reference fuel. In addition, different speed intervals, which include 1000 RPM, 2000 RPM, and 5000 RPM, are employed for each fuel blend. The production of four major emissions, NOx, CO, CO2, and HC, and performance parameters such as thermal efficiency, volumetric efficiency, and brake-specific fuel consumption, are evaluated using SolidWorks for CAD modelling. This then is transferred to ANSYS for emission and performance analysis. According to the findings, increasing ethanol concentration and engine speed increases volumetric efficiency and brake-specific fuel consumption by up to 12.89% and 6.59%, respectively. It was also discovered that ethanol and increasing engine speed had an 11.39% reduction in thermal efficiency. Furthermore, the addition of ethanol occurs, along with an increase in speed, exhaust gas emissions are reduced by up to 21.74% compared to pure gasoline

    The serum thyroid hormone profile in mechanically ventilated children: Does euthyroid sick syndrome exist?

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    Background: The term "euthyroid sick syndrome" refers to alterations in thyroid function testing during critical illness. Mechanically ventilated children's thyroid hormone levels may be altered, although the reason for this remains a mystery.Objective: This study was aimed to evaluate thyroid hormone profile in mechanically ventilated children and their correlation with mortality.Patients and Methods: Thirty-four mechanically ventilated children were enrolled in a prospective cohort study. On the first and third days of mechanical ventilation, serum TSH, FT3, FT4 and reverse T3 were measured.Results: The mean age of the studied patients was of 31.06 ± 35.94 months. After three days of mechanical ventilation, the serum levels of FT3 and FT4 in the blood were significantly lower than the serum levels on the first day. The serum reverse T3 levels increased significantly on the third day of mechanical ventilation compared to the first day. There was a statistically significant increase in the number of patients with low FT3 and FT4 serum levels on the third day compared to the first day. Twenty-two patients (64.7%) died, and the frequency of low FT3 among dead patients was signiisignificantlycantly higher than among surviving patients.Conclusions: It could be concluded that the mechanically ventilated children had signs of euthyroid sick syndrome, shown by low levels of FT3 and FT4 and a rise in rT3 without a compensatory rise in TSH. Serum FT3 and FT4 decreased, but reverse T3 increased, on the third day of mechanical ventilation compared to the first day. Patients who had low FT3 levels died at a higher rate

    Impact of a Designed Nursing Intervention Protocol about Preoperative Liver transplantation Care on Patients’ Outcomes at A University Hospital in Egypt

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    Background: Literature review cited that, Liver transplantation is now considered as the gold standard for treatment of patients with end-stage liver diseases and early liver tumors in cirrhotic livers. Patient education is vital to the safety and success of a transplant. Aim: the aim is to assess the impact of a designed nursing intervention protocol about preoperative liver transplantation care on patient’s outcomes as indicated by: patients` knowledge & practice mean scores, and complications developed. To fulfill the aim of this study, the following hypothesis was formulated: patients undergoing liver transplantation who will be exposed to the designed nursing intervention protocol about preoperative liver transplantation care will show better outcomes. Material and Methods: A convenient sample of 14 adult male and female patients admitted to Liver Transplant Unit at El Manial University Hospital were included, three of them were died with an attrition rate of 21.4%. Four tools were formulated to collect data pertinent to the study. 1- Sociodemographic and medical data sheet; 2- Pre/Post knowledge assessment questionnaire sheet, 3- Observational checklists, & 4- Complications assessment sheet. Structured interview, reviewing medical records, direct observation and physical examination were utilized for data collection. Results: a  significant statistical difference was found in relation to the total and subtotal mean knowledge and practice scores during different assessment periods  with P values (0.00 for both); as well, 45.5 %  of patients developed respiratory complications (pleural effusion) compared to 53.8 % of their correspondence who developed respiratory complications (pleural effusion, chest infection, and others), in addition, 9.1% of the studied subjects developed  rejection, and ascites as compared to (1.9 %, 5.7%) of their correspondence over the last consecutive three years respectively. Conclusion: Liver transplantation patients showed a positive improvement in their knowledge and practice in relation to breathing, coughing, & using respirometer exercises and range of motion. Replication of this study on a larger sample selected from different geographical areas is highly recommended. Key wards: liver transplantation, designed nursing intervention protocol, preoperative liver transplantation care, knowledge, complications, and patient`s outcome

    Synthesis and biological evaluation of phthalimide dithiocarbamate and dithioate derivatives as anti-proliferative and anti-angiogenic agents-I

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    A facile synthesis of new phthalimide dithiocarbamate and dithioate analogs 8a-j, 9a-e and 9g-j were achieved by the reaction of N-chloromethyl and N-bromoethylphthalimide with carbon disulfide (CS2) and various amines. The structures of the synthesized analogs were elucidated by spectroscopic methods, including IR, 1H NMR and 13C NMR, and ESI-HRMS techniques. The antiproliferative activity of the newly synthesized compounds was also evaluated against various human cancer cell lines. The compound 9e and 9i exhibited the highest activity against human breast adenocarcinoma MCF-7 and hepatocellular carcinoma HepG2 cells. Compound 8f showed better antiproliferative effect against colon carcinoma HCT-116 and cervical carcinoma HeLa compared to thalidomide. The binding affinity to vascular endothelial growth factor receptor (VEGFR) of some compounds was assessed in addition to molecular docking study. Compounds 9e and 9i showed high docking score values and they significantly declined the concentration of VEGFR

    Photometric and Spectroscopic Analysis of the SX Phe Star BL Cam

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    In the present paper, we report the photometric and spectroscopic observations obtained by the 1.88 m telescope at the Kottamia astronomical observatory of the pulsating star BL Cam. Fourier analysis of the light curves reveals that the fundamental mode has two harmonics. The O-C method is used to establish the period changes. So far, the analysis has been very successful in mapping the pulsation amplitude of the star across the instability strip. By using the formalism of Eddington and Plakidis (1929), we found significant results and strong indications of the evolutionary period change. A total of 55 new maximum light timings are reported. New values of (1/P) dP/dt are estimated using the O-C diagram based on all newly obtained times of maximum light combined with those taken from the literature, assuming the periods are decreasing and changing smoothly. To compute the effective temperature and surface gravity of the star, we performed model atmosphere analysis on its spectra. The physical parameters of the star are calculated and compared with the evolutionary models

    Pharmacology of the Autonomic Nervous System

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    This comprehensive chapter delves into the intricate landscape of autonomic nervous system (ANS) pharmacology. It meticulously explores both agonists and antagonists pharmacology that work on the sympathetic and parasympathetic divisions. This chapter covers direct and indirectly acting drugs and thoroughly explains receptor interactions. The content spans a wide array of examples, elucidating these agents’ mechanisms and clinical applications. Through a detailed examination of pharmacokinetics, metabolism, adverse effects, and contraindications, healthcare professionals gain the insights needed to navigate the complexities of ANS modulation. This knowledge equips practitioners to harness the potential of autonomic drugs, facilitating optimal therapeutic outcomes across diverse medical scenarios

    Fetuin-A and Ghrelin Levels in Children with End Stage Renal Disease and the Effect of a Single Hemodialysis Session on Them

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    BACKGROUND: Fetuin-A and ghrelin have been implicated in cardiovascular diseases and mortality among end stage renal disease patients. The exact mechanisms have not been fully elucidated. There is robust data supporting an association between ghrelin and various cardiovascular conditions, and some common processes such as inflammation, oxidative stress, and endoplasmic reticulum stress have been implicated.AIM: This study was conducted to assay serum fetuin-A and ghrelin in chronic renal failure pediatric patients and to study changes in their level that may occur after a single hemodialysis.MATERIAL AND METHODS: Forty nine pediatric patients suffering from ESRD on maintenance hemodialysis (HD), 20 patients with chronic renal failure (CRF) not on dialysis and 35 healthy subjects as control group were included. The mean age of the study population was 10.58 ± 3.94, 10.62 ± 3.24 and 10.61 ± 3.97 years respectively. Serum fetuin-A and plasma acyl ghrelin levels were measured by using ELISA method.RESULTS: The present study revealed that predialysis serum fetuin-A level was significantly increased in pediatric HD patients compared with the normal population, while ghrelin levels were significantly reduced. Furthermore, serum levels of fetuin-A decreased significantly after a single HD session.CONCLUSION: Our study concluded that fetuin-A and acyl ghrelin may play a role in inflammatory process among HD pediatric patients which may account for cardiovascular insults and mortality but their use as biochemical markers among ESRD pediatric patients have limitations due to wide fluctuations
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