581 research outputs found
Solving Modal Equations of Motion with Initial Conditions Using MSC/NASTRAN DMAP
By utilizing MSC/NASTRAN DMAP (Direct Matrix Abstraction Program) in an existing NASA Lewis Research Center coupled loads methodology, solving modal equations of motion with initial conditions is possible using either coupled (Newmark-Beta) or uncoupled (exact mode superposition) integration available within module TRD1. Both the coupled and newly developed exact mode superposition methods have been used to perform transient analyses of various space systems. However, experience has shown that in most cases, significant time savings are realized when the equations of motion are integrated using the uncoupled solver instead of the coupled solver. Through the results of a real-world engineering analysis, advantages of using the exact mode superposition methodology are illustrated
Solving modal equations of motion with initial conditions using MSC/NASTRAN DMAP. Part 1: Implementing exact mode superposition
Within the MSC/NASTRAN DMAP (Direct Matrix Abstraction Program) module TRD1, solving physical (coupled) or modal (uncoupled) transient equations of motion is performed using the Newmark-Beta or mode superposition algorithms, respectively. For equations of motion with initial conditions, only the Newmark-Beta integration routine has been available in MSC/NASTRAN solution sequences for solving physical systems and in custom DMAP sequences or alters for solving modal systems. In some cases, one difficulty with using the Newmark-Beta method is that the process of selecting suitable integration time steps for obtaining acceptable results is lengthy. In addition, when very small step sizes are required, a large amount of time can be spent integrating the equations of motion. For certain aerospace applications, a significant time savings can be realized when the equations of motion are solved using an exact integration routine instead of the Newmark-Beta numerical algorithm. In order to solve modal equations of motion with initial conditions and take advantage of efficiencies gained when using uncoupled solution algorithms (like that within TRD1), an exact mode superposition method using MSC/NASTRAN DMAP has been developed and successfully implemented as an enhancement to an existing coupled loads methodology at the NASA Lewis Research Center
Fifteen years experience: Egyptian metabolic lab
Background: Inborn errors of metabolism (IEM) are single gene disorders responsible for abnormalities in the synthesis or catabolism of proteins, carbohydrates and fats by means of defective enzymes or transport proteins which results in a block of the metabolic pathway and accumulation of metabolites in different tissues. This study shows the most common diagnosed inherited inborn errors of metabolism among the Egyptian population. Prior to 1995, the diagnosis of inherited metabolic disorders in Egypt was very limited and diagnosed mainly on clinical suspicion. In 1995, The Biochemical Genetics Unit at The National Research Centre has been established as a part of The Human Genetics Department and later on in 2003 it was developed into The Biochemical Genetics Department by applying advanced techniques and equipments and providing early diagnosis for the metabolic disorders which led to better outcome in our patients. Material and methods: We have retrospectively reviewed a total of 12,148 cases suspected to have inborn errors of metabolism (IEM) with different age groups. They had been referred from several diagnostic centers and hospitals in Egypt to The Department of Biochemical Genetics at The National Research Centre. The diagnosis of these disorders was confirmed by qualitative determination of amino acid profile, quantitative determination of phenylalanine and galactose levels using dried blood spots (DBSs), quantitative determination of urinary glycosaminoglycans (GAGs), twodimensional electrophoretic separation of GAGs in urine and the assay for lysosomal enzymes activities in plasma and leukocytes. Results: Out of the total number of cases; 1041 (8.6%) patients were proved to have metabolic disorders. Those patients were classified as: 722 patients (69.4%) with lysosomal storage disorders, 302 patients (29%) with amino acid disorders and 17 patients (1.6%) with galactosemia. Conclusion: This study illustrates the experience of the reference metabolic lab in Egypt over 15 years. The lab began metabolic disorder screening by using simple diagnostic techniques like thin layer chromatography and colored tests in urine which by time updated and upgraded the methods to diagnose a wide range of disorders. This study shows the most common diagnosed inherited inborn errors of metabolism among the Egyptian population.Keywords: IEM; Consanguineous marriages; Aminoacidopathies; Lysosomal storage disorder
Effect of police training during the confinement period on some cardiopulmonary and hematological parameters in Khartoum, Sudan
Background: Pulmonary function tests (PFT) serve as a tool of health assessment and as a predictor of occupational fitness. Police officers must develop and maintain high levels of physical fitness for physical demanding tasks they perform. The training program starts with confinement of five to eight weeks according to the trainee. Previously it has been shown that the police students have better lung functions values compared to their civilian colleagues. In this study the effect of the confinement training on pulmonary function tests was investigated.Methods: Eighty one policemen trainee were randomly selected from a new batch in the faculty of police sciences and Law, the National Ribat University, Khartoum, Sudan at their starting confinement period. Subjects were medically fit with no history of Diabetes, Hypertension, Asthma or use of any long term medications. Pulmonary function tests (FVC, FEV1 and PEFR) were performed using a micro-plus spirometer. Blood pressure, pulse rate, and hemoglobin were measured. All these were repeated at the end of the confinement.Results: The age of participants ranged from 24 to 26 years. FVC, FEV1 and PEFR significantly increased after the confinement period. The blood pressure and the pulse significantly decreased. The weight of the participants decreased after the confinement but Hb significantly slightly increased.Conclusions: Regular police training during the confinement improved the pulmonary and cardiovascular reserve function
Attitudes of Saudi Mothers Towards Breastfeeding: A Cross–Sectional Survey in Taif Region, Saudi Arabia
Background: Mothers’ attitudes are strong predicators of choice of infant feeding method. This study was conducted to measure attitudes towards breastfeeding among Saudi mothers.
Methods: A cross-sectional survey was conducted during April 2013 among Saudi nursing mothers in Taif Region; Kingdom of Saudi Arabia (KSA). Data was collected by trained pharmacy female students through face-to-face interview method using structured questionnaire. Mothers’ attitudes towards breastfeeding were assessed by The Iowa Infant Feeding Attitude Scale (IIFAS).
Results: A total of 387 mothers were included of them 204 (52.7%) aged < 32 years and 334 (86.3%) were residents in the town. University or college graduates were 262 (67.7%). Overall 181 (46.8%) of the mothers had positive attitudes towards breastfeeding, while 206 (53.2%) held negative ones. Correlating mothers’ total attitudes towards breastfeeding to their demographics showed that; out of the mothers aged < 32 years 118 (57.8%) had significantly more positive attitudes than older ones (aged > 32 years) 63 (34.4%), (P < 0.001). Cross tabulation of the method of infant feeding and mothers’ total attitudes towards breastfeeding showed that mothers used formula feeding or mixed feeding method 120 (49.0%) had significantly positive attitudes towards breastfeeding more than breastfeeding ones 61(43.0%), (P =0.025).
Conclusion: The rate of exclusive breastfeeding was low. Positive attitudes towards breastfeeding was found to be more among mothers used formula or mixed feeding method. Educational interventions are needed to raise awareness and upgrade mothers’ knowledge on infant breastfeeding
First documented presence of Galeocerdo cuvier (Péron & Lesueur, 1822) (ELASMOBRANCHII, CARCHARHINIDAE) in the Mediterranean basin (Libyan waters)
One male and one female specimen of tiger shark, Galeocerdo cuvier (Peron & Lesueur, 1822), were accidentally caught by a drifting longline for swordfish in the south Mediterranean (Libyan waters). This finding confirms beyond any doubt that the tiger shark may be encountered in the waters of the Mediterranean Sea. Although records of this species has previously been reported, the information is partial or dubious, due to the lack of a description of the individuals found or the uncertain provenance of preserved material. Our finding confirms the record of this species in the southern part of the Mediterranean basin. Images, as well as morphometrics and information on stomach contents are given. Based on the size of the individuals, it is considered that the two specimens were born recently, presumably inside the Mediterranean Sea and likely close to the area where the individuals were found
Shear Performance of GFRP Reinforced Concrete Beams with Seawater and Chopped Fiber
This paper reports an experimental study on the behavior and shear strength of concrete beams reinforced with longitudinal GFRP bars mixed with sea water. In order to evaluate how much concrete contributes to shear resistance, seven beams were tested in bending. Similar in size and concrete strength, the beams were longitudinally reinforced with glass fiber-reinforced polymer bars; however, they did not even have shear reinforcement. The beams, which measured 3,100 mm in length, 400 mm in depth, and 200 mm in width, were conducted and tested up to failure. The test variables were longitudinal reinforcement ratios (1.0, 1.4, and 2.0%), chopped fiber content (0, 0.5, 2, and 3 kg/m3), and mixing water type (freshwater and seawater). The test findings showed that increasing the reinforcement ratio increased the neutral-axis depth and allowed the formation of more closely spaced fractures while decreasing the loss of flexural stiffness after cracking. By increasing the area of concrete in compression, this in turn enhances the contribution of aggregate interlock as well as the contribution of uncracked concrete. Furthermore, increasing the reinforcement ratio improves the dowel action, which reduces the tensile stresses that are created in the concrete around it. Doi: 10.28991/CEJ-2023-09-04-05 Full Text: PD
Potential Role of New Anthropometric Parameters in Childhood Obesity with or Without Metabolic Syndrome
BACKGROUND: Obese children and adolescents are more prone to have metabolic syndrome (MS).MS is a cluster of cardiovascular risk factors associated with insulin resistance. Body round index [BRI], visceral adiposity index [VAI] and a body shape index [ABSI] are among the new obesity anthropometric parameters.
AIM: To evaluate the new markers for obesity in children and their possible association with other laboratory and clinical variables of MS.
METHODS: Eighty nine obese children and 40 controls aged 10-18 years were recruited. Full history taking, thorough clinical examination, anthropometric and biochemical features were performed in the studied groups. Subcutaneous fat thickness (SFT) and visceral fat thickness (VFT) were estimated by ultrasonography.
RESULTS: Obese children, exhibited significantly higher values in all anthropometric measurements (P < 0.001). Diastolic and systolic blood pressure were significantly higher (P < 0.001) in the obese group. ABSI, BRI and VAI have been found to be significantly higher in obese subjects (P < 0.001), with no significant gender difference. BMI, WHtR, WC/HR, SBP, DBP, subcutaneous fat thickness and visceral fat thickness, Liver Span, ABSI, BRI, VAI and HOMA_IR were significantly higher among children with MS than those without MS. Positive significant correlations of VAI with BMI, WC/Ht, WC/Hip, SBP, DBP, SFT, VFT, Liver size and HOMA-IR (r = 0.384, 0.239, 0.268, 0.329, 0.516, 0.320, 0.254, 0.251, and 0.278 respectively) are shown. The area under the ROC curve (AUC) of BMI, VAI, ABSI, BRI for predicting MS was 0.802 (0.701-0.902), 0.737 (0.33-0.841), 0.737 (0.620-0.855), 0.816 (0.698-0.934).
CONCLUSION: We suggest using the VAI and WHtR indexes, as they are better predictor of MS
POTENTIAL ROLE OF MILK THISTLE SEED AND ITS OIL EXTRACTS AGAINST HEART AND BRAIN INJURIES INDUCED BY γ-RADIATION EXPOSURE
Objective: This study aimed to investigate the protective effect of Silybum marianum (S. marianum) seeds extract its oil fraction against damage effect of γ-radiation in female albino rats.Methods: Ultrasonic-assisted extraction was used for the extraction of S. marianum seeds. Lipid patterns of S. marianum seeds oil were elucidated using gas chromatography-mass spectrometry (GC-MS). S. marianum seeds extract was analyzed using high-performance liquid chromatography (HPLC). Malondialdehyde (MDA), reduced glutathione (GSH) and metallothionein (MT) were estimated in heart and brain tissues of the examined rats. Lactate dehydrogenase (LDH) and creatine kinase-MB (CKMB) were measured in the serum of the examined rats, and the brain biomarkers; dopamine and serotonin were also measured.Results: The oil was found to be rich in linoleic acid (58.20%) and arachidic acid (23.38%). S. marianum seeds extract revealed the presence of taxifolin and six main active constituents of silymarin, including silydianin, silychristin, silybin A, silybin B, isosilybin A and isosilybin B. Treatment of γ-radiation damage effect using S. marianum seeds extract and its oil fraction led to a significant reduction of MDA levels in heart (139.6 and 165.5 nmol/g, respectively) and brain (158.5 and 135.2 nmol/g, respectively) tissues, however, significant increase of GSH levels in heart (316.4 and 293 mg/g, respectively) and brain (210.4 and 227 mg/g, respectively) tissues was observed, also a significant increase of dopamine levels (85.27 and 65.74 ng/g, respectively) and MT levels of heart tissues (108.5 and 70.52 mg/g, respectively) was observed.Conclusion: S. marianum seeds extract and its oil fraction showed a protective effect against γ-radiation-induced damage in heart and brain.Â
Vitamin D Receptor Gene (Fok-I) Polymorphisms in Type 1 Diabetic Children; Case Study in Zagazig University Hospitals
Background: Many meta-analyses studied the association between vitamin D receptor (VDR) gene polymorphism and type 1 diabetes (T1DM) susceptibility.
Objective: This study was designed to assess the role of VDR gene (FOK-I) polymorphisms in type 1 diabetic children from Zagazig University Hospitals in Egypt.
Patients and Method: In this case-control study, the genotypes of VDR gene (FOK-I) polymorphisms were assessed in 180 type 1 diabetic children and 120 healthy matched age controls by PCR-RFLP analysis.
Results: A high statistical difference between patient and control regarding VDR gene (FOK-I) polymorphisms, where 44% of the patient group had heterozygous genotype (AG) compared to 8.3% in the control group. AG genotype has almost a higher risk nine times odds ratio (OR) = 8.8 than AA genotype in diabetic patients. There was a significant increase in the G allele in the patient group. Moreover, a significant association between (FOK-I) polymorphisms and T1DM complications was also observed.
Conclusion: (AG) genotype of VDR gene (FOK-I) polymorphisms could be a risk factor for T1DM complications. So, VDR gene (FOK-I) polymorphisms should be performed with other genetic studies for early prediction, detection and prevention of microvascular complications of T1DM that adversely affect health-related quality of life of Egyptian children and burden the primary care units
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