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Crystallization of osumilite from modified basaltic glasses
Osumilite-type phases, which have high temperature stability and low linear thermal expansion coefficients, were crystallized from modified basalt glass composition. To satisfy the compositional requirements of osumilite molecules, a deliberate amount of kaolin, sand, magnesite and TiO2 should be added to the basalt. The crystallization process was investigated by DTA, X-ray diffractometry and SEM. The effect of compositional changes on bulk crystallization and growth morphology was also studied. The linear thermal expansion coefficient was measured to characterize the produced glass-ceramics
The Level of Ischemic Modified Albumin (IMA) as Risk Marker for Cardio Vascular D isease (CVD) among some diabetic patients (type II) in Khartoum state -Sudan
Background. Recent literature reports show large interest in ischemic modified albumin (IMA) biochemical marker for detection of myocardial injury. Special attention is focused in estimation of IMA test for the diagnosis and evaluation of myocardial ischemia as well as others acute coronary syndrome in emergency patients.Objective : evaluation of ischemia-modified albumin (IMA) in well controlled and uncontrolled patients with type 2 diabetes mellitus and estimation of its connection with cardiovascular disease.Measurement thelevelof IMA asrisk marker forcardio vascular disease (CVD) in diabetic patients that arrivedtoemergency department with signs and symptoms of CVD.Methodology. 140 subjects enrolled in thisstudy ,70 diabetes mellitus patients with signs and symptoms of CVD, and other 70 apparently non diabetic healthy subjects' as controls, , the levels of biomarker IMA was measured as the risk marker ofCVDin controlled and uncontrolleddiabeticpatients with type2,the Diagnostic potential was evaluated by receiver operating characteristic analysis and their relationships were analyzed. This study was donein Shab Hospital, Khartoum.Period from 1st of February 2015 to October 2015.Results: The results showed that CVD were predominant among diabetic female 57 % and peaked at age 75.5 years among 40-75 year old. The IMA was significantly increase in diabetic patients when compare with normal healthy group with cut off value ( 0.97 IU/L ), and there is also significantly increase in IMA level in uncontrolled diabetic patients (Mean ± SD; 14.70 + 10.66) that presented with acute chest pain and havea signs and symptoms of cardiac ischemia when compared with the well-controlled diabetic patients(Mean ± SD; 3.74 + 3.68). controlled and uncontrolled diabetic patients were determined by the level of their HBA1c and comparison with the means of IMA level in their serum.Conclusions: increase IMA level in poor control and long stand diabetic patients could help to identify the higher risk for develop to CVD, and The most common complication such as suffering from local or systemic hypoxic conditions, as acute ischemic stroke, peripheral vascular disease.Keywords: Ischemia, Type 2 diabetes mellitus, cardiovascular disease, Ischemic Modified Albumi
The level of Ischemic Modified Albumin (IMA) as risk marker for Cardio Vascular Disease (CVD) among some diabetic patients (type II) in Khartoum State-Sudan
Background: Recent literature reports show large interest in ischemic modified albumin (IMA) biochemical marker for detection of myocardial injury. Special attention is focused in estimation of IMA test for the diagnosis and evaluation of myocardial ischemia as well as others acute coronary syndrome in emergencypatients.Objective: evaluation of ischemia-modified albumin (IMA) in well controlled and uncontrolled patients with type 2 diabetes mellitus and estimation of its connection with cardiovascular disease.Measurement the levelof IMA as risk marker for cardio vascular disease (CVD) in diabetic patients that arrived to emergency department with signs and symptoms of CVD.Methodology: 140 subjects enrolled in this study ,70 diabetes mellitus patients with signs and symptoms of CVD, and other 70 apparently non diabetic healthy subjects’ as controls, , the levels of biomarker IMA was measured as the risk marker of CVDin controlled and uncontrolled diabeticpatients with type2,the Diagnostic potential was evaluated by receiver operating characteristic analysis and their relationships were analyzed. This study was done in Shab Hospital, Khartoum. Period from 1st of February 2015 to October 2015.Results: The results showed that CVD were predominant among diabetic female 57 % and peaked at age 75.5 years among 40-75 year old. The IMA was significantly increase in diabetic patients when compare with normal healthy group with cut off value ( 0.97 IU/L ), and there is also significantly increase in IMA level in uncontrolled diabetic patients (Mean ± SD; 14.70 + 10.66) that presented with acute chest pain and havea signs and symptoms of cardiac ischemia when compared with the wellcontrolled diabetic patients (Mean ± SD; 3.74 ± 3.68). controlled and uncontrolled diabetic patients were determined by the level of their HBA1c and comparison with the means of IMA level in their serum.Conclusions: increase IMA level in poor control and long stand diabetic patients could help to identify the higher risk for develop to CVD, and The most common complication such as suffering from local or systemic hypoxic conditions, as acute ischemic stroke, peripheral vascular disease.Keywords: Ischemia, Type 2 diabetes mellitus, cardiovascular disease, Ischemic Modified Albumi
Effects of space plasma on an oxide coating of spacecraft's surface materials
The aim of this paper is to study the properties of the materials for spacecraft surfaces under the effects of simulated low Earth orbit (LEO) plasma environment to understand the effects of charging and discharging phenomena, which are known to take place when spacecraft is moving through space plasma in LEO. Anodized aluminum Al2O3 samples were prepared using electrochemical techniques with different thicknesses to investigate the role of the Al2O3 coating in the charging and discharging phenomena. Penning plasma source is used to generate plasma using Ar gas flowing through the vacuum chamber. The peak current and the voltage waveform associated with charging and discharging processes, when a negatively biased voltage is applied to the substrate, are discussed. The structural properties before and after plasma exposure are investigated through the morphology and optical analyses of the samples. Morphological analyses confirmed the significant contribution of space plasma in the variation of the crystalline structure, and sample characteristics are dependent on the value of the thickness. In addition, the results confirm the variation of optical properties and the microcrystalline structure over the surface of the anodic oxide film
Sensitivity of Non-Contrast Computed Tomography for Small Renal Calculi with Endoscopy as the Gold Standard
Objectives
To compare the sensitivity of non-contrast CT to endoscopy for detection of renal calculi. Imaging modalities for detection of nephrolithiasis have centered on abdominal x-ray (KUB), ultrasound (US), and non-contrast computed tomography (CT). Sensitivities of 58-62% (KUB), 45% (US), and 95-100% (CT) have been previously reported. However, these results have never been correlated with endoscopic findings.
Methods
Idiopathic calcium oxalate stone formers with symptomatic calculi requiring ureteroscopy (URS) were studied. At the time of surgery, the number and location of all calculi within the kidney were recorded followed by basket retrieval. Each calculus was measured and sent for micro CT and infrared spectrophotometry. All CT scans were reviewed by the same genitourinary radiologist who was blinded to the endoscopic findings. The radiologist reported on the number, location, and size of each calculus.
Results
18 renal units were studied in 11 patients. Average time from CT scan to URS was 28.6 days. The mean number of calculi identified per kidney was 9.2±6.1 for endoscopy and 5.9±4.1 for CT (p<0.004). The mean size of total renal calculi (sum of longest stone diameters) per kidney was 22.4±17.1 mm and 18.2±13.2 mm for endoscopy and CT, respectively (p=0.06).
Conclusions
CT scan underreports the number of renal calculi, probably missing some small stones and unable to distinguish those lying in close proximity to one another. However, the total stone burden seen by CT is, on average, accurate when compared to that found on endoscopic examination
Sensitive Determination of Moxifloxacin HCl in Pharmaceuticals or Human Plasma Using Luminescence or Eye Vision
A new probe based on the complex of 1,2 dihydro-2-oxoquinoloine-4-carboxylic acid (DOCA) as a ligand with Europium (III) ion was developed for the quantitation of Moxifloxacin HCl (Moxi.HCl) in pharmaceuticals and human plasma using a luminescence method. The metal to ligand ratio of the complex is 1:2 as determined by a Job plot. The determination of Moxi.HCl is based on static quenching of the luminescence of the probe upon coordination of Moxi.HCl. The negative value for ΔG proves that this reaction is spontaneous. The calibration curve was constructed based on a Stern–Volmer equation and the quantitation range was 0.05–80 µg mL−1. This is low enough to determine the drug in blood plasma, even hours after administration, which is not feasible with the methods published so far. The LOD was 15 ng mL−1. The accuracy of the method was demonstrated by good recoveries of spiking experiments in tablets, ophthalmic eyedrops and human blood plasma, where the mean recovery was 99% with RSDs below 5%. The method was validated by closely matching concentrations of the drug found in all these real samples by HPLC. Additionally, Moxi.HCl can be assessed semi-quantitatively by eye vision upon excitation with a UV lamp at 365 nm by a gradual color shift from red to blue with increasing concentrations of Moxi.HCl
Electrical performance of efficient quad-crescent-shaped Si nanowire solar cell
The electrical characteristics of quad-crescent-shaped silicon nanowire (NW) solar cells (SCs) are numerically analyzed and as a result their performance optimized. The structure discussed consists of four crescents, forming a cavity that permits multiple light scattering with high trapping between the NWs. Additionally, new modes strongly coupled to the incident light are generated along the NWs. As a result, the optical absorption has been increased over a large portion of light wavelengths and hence the power conversion efficiency (PCE) has been improved. The electron–hole (e–h) generation rate in the design reported has been calculated using the 3D finite difference time domain method. Further, the electrical performance of the SC reported has been investigated through the finite element method, using the Lumerical charge software package. In this investigation, the axial and core–shell junctions were analyzed looking at the reported crescent and, as well, conventional NW designs. Additionally, the doping concentration and NW-junction position were studied in this design proposed, as well as the carrier-recombination-and-lifetime effects. This study has revealed that the high back surface field layer used improves the conversion efficiency by ∼ 80%. Moreover, conserving the NW radial shell as a low thickness layer can efficiently reduce the NW sidewall recombination effect. The PCE and short circuit current were determined to be equal to 18.5% and 33.8 mA/cm for the axial junction proposed. However, the core–shell junction shows figures of 19% and 34.9 mA/cm. The suggested crescent design offers an enhancement of 23% compared to the conventional NW, for both junctions. For a practical surface recombination velocity of 10 cm/s, the PCE of the proposed design, in the axial junction, has been reduced to 16.6%, with a reduction of 11%. However, the core–shell junction achieves PCE of 18.7%, with a slight reduction of 1.6%. Therefore, the optoelectronic performance of the core–shell junction was marginally affected by the NW surface recombination, compared to the axial junction
A Comparative Study of Prediction Techniques for Supersonic Missile Aerodynamic Coefficients / Loai A. El-Mahdy … [et al.]
Evaluating the aerodynamic coefficients of flying vehicles such as missiles is a key step in their design and development procedures. In practice, the aerodynamic coefficients can be estimated using experimental measurements, numerical simulations, or using empirical and semi-empirical engineering tools. In the present paper, these three approaches are compared in the context of examining the aerodynamic coefficients of a fin-stabilized tactical missile. Supersonic flight conditions up to Mach 4 at incidence up to 18 degrees are considered. Lift and drag coefficients as well as the centre of pressure locations based on the three approaches are compared. The flow features around the missile are explored based on the numerical simulations
Dietary Behaviour Pattern and Physical Activity in Overweight and Obese Egyptian Mothers: Relationships with Their Children's Body Mass Index
BACKGROUND: Obesity and related morbidity increase in Egyptian women and their children. A better understanding of dietary and activity patterns is needed to reduce obesity prevalence.AIM: The present study aimed to assess dietary patterns and physical activity in Egyptian overweight and obese mothers and to explore its relationships with their children's body mass index (BMI).SUBJECTS AND METHODS: This descriptive case-control study was conducted at the National Research Center. The study included a sample of 64 overweight and obese mothers and 75 children, compared with apparently healthy non-obese mothers and their children of matched age and social class. Tested questionnaires were used to collect information of the studied subjects.RESULTS: A statistically significantly higher incidence of unemployment, large family size was observed in overweight & obese women compared to controls (P < 0.05). Those women who consumed vegetables more than 3 times a week were less likely to be overweight or obese (P < 0.05). No significant association were detected between mothers' physical activity, dietary behaviour variables and children’s BMI except for consuming beverages with added sugar (95%CI = 0.074-0.985, P<0.05).CONCLUSION: Improper dietary patterns, nonworking mothers and big family size are associated with obesity among Egyptian women. Emphasis should be given to increasing physical activity and encourage healthier diets among Egyptian mothers and their children
Ethical, legal and social aspects of the approach in Sudan
The global malaria situation, especially in Africa, and the problems frequently encountered in chemical control of vectors such as insecticide resistance, emphasize the urgency of research, development and implementation of new vector control technologies that are applicable at regional and local levels. The successful application of the sterile insect technique (SIT) for the control of the New World screwworm Cochliomyia hominivorax and several species of fruit flies has given impetus to the use of this method for suppression or elimination of malaria vectors in some areas of Africa including Northern State of Sudan. The research and development phase of the Northern State feasibility study has been started. Sudanese stakeholders are working side-by-side with the International Atomic Energy Agency in the activities of this important phase. Several ethical, legal and social issues associated with this approach arose during this phase of the project. They need to be seriously considered and handled with care. In this paper, these issues are described, and the current and proposed activities to overcome potential hurdles to ensure success of the project are listed
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