Investigating the Effectiveness of Digital-Based Concept Mapping on Teaching Educational Technology for Undergraduate Students

The purpose of this study was to investigate the effects of using digital-based concept mapping as strategy on students’ achievements and attitudes. Data was collected from 58 students enrolled in the course of ”Introduction to Educational Technology” in Instructional and Teaching Technologies Department at Sultan Qaboos University. Two sections out of four sections were selected randomly as the sample of the study. One of the sections was randomly chosen as experimental group (n = 27) and the other was control group (n = 31). Both pre- and post- achievement tests were used. The results of the study revealed that students who were taught with digital-based concept mapping strategy performed better than those who were taught with the conventional method. There was a significant difference between male and female students in the post test scores of the experimental group in favor of females. In addition, no interaction effect for the independent variables was found. The study also showed that students in the experimental group had positive attitude towards using digital-based concept mapping in learning edu- cational technology

Dyslipidemia among Sudanese Children Undergoing Maintenance Dialysis

Introduction: Dyslipidemia is an established risk factor for atherosclerosis and cardiovascular disease. It is common among children undergoing maintenance dialysis. To our knowledge, this is the first report on the lipid profile of children undergoing maintenance hemodialysis (HD) or continuous ambulatory peritoneal dialysis (CAPD) in Sudan. Methods: We studied 17 children on HD, 11 children on CAPD and 28 controls. The levels of total cholesterol (TC), triglycerides (TGD) and high density lipoprotein cholesterol (HDL-C) were measured from fasting serum samples using electrophoresis and low density lipoprotein cholesterol (LDL-C) was then calculated. Results: End stage renal failure (ESRF) children had higher mean TC (193±36 versus 135±17 mg/dl), higher mean TGD (120±38 versus 90±15 mg/dl), higher mean LDL-C (129±32 versus 69±18 mg/dl), and lower mean HDL-C (39±12 versus 49±4 mg/dl) than controls (P=0.00 for all parameters). CAPD patients had higher mean TC (211±39 versus 181±30 mg/dl) and higher LDL-C (145±35 versus 118±25 mg/dl) than controls (P=0.03 for both parameters). The prevalence of dyslipidemia among ESRF patients was 75% while none of the control group had lipid parameters outside the accepted range. Among ESRF patients, 39.3% had TC > 200 mg/dl, 21.4% had TGD > 150 mg/dl, 42.9% had LDL-C > 130 mg/dl, and 35.7% had HDL-C < 35 mg/dl. Abnormal HDL-C values were more prevalent among CAPD patients compared to HD patients (52.9% versus 9.1%, P=0.02) Conclusion: Despite the small number of studied children, this study is likely to reflect the high prevalence of dyslipidemia among children undergoing maintenance dialysis treatment in Sudan. Keywords: Children; Continuous Ambulatory Peritoneal Dialysis; Dyslipidemia; Hemodialysis; Suda

Mitigation of train-induced vibrations on nearby high-rise buildings by open or geofoam-filled trenches

The vibrations induced by moving trains especially in close distances with high-rise buildings can be destructive. The high technology of wilding rails induced a high train velocity which is associated with high vibrations. The buildings near the railways suffer from the train-induced vibrations. In this paper, a 3D FEM model was constructed to study the train-induced vibrations on a nearby high-rise building (HRB), show its response and investigate the most suitable technique to mitigate the effect of the train-induced vibrations by an open trench or a geofoam-filled trench. Three trench parameters were investigated to enhance the mitigation performance, the distance from the trench to the HRB, the trench depth and the use of either open (empty) trench or geofoam-filled trench. The geofoam-filled trench technique improved the dynamic response of the structure. Thus, trenches filled with geofoam can be considered a protection technique for high-rise buildings constructed near moving trains

Properties of High-Performance Concretes made of Black Sand at High Temperature

To modify high-performance concrete (HPC) fireproofing properties, black sand (BS) was partially substituted as fine aggregate at various levels. This study aims at evaluating the BS reliability in improving HPC durability properties for various construction applications based on its unique heavy minerals. To achieve this, five HPC series blends were setup to substitute fine aggregate independently with BS. Substitution percentages ranged from 15 to 100% with consistent supplementary cementing materials (SCMs) proportion for each gathering. Tests were performed to assess compressive strength before and after fire exposure under various temperatures of 250, 500 and 750 °C at different curing age. Generally, blending FA with BS was better than using SF with BS. Utilizing BS in the range of 15 to 60% as fine aggregate with 10% FA improves HPC fire-insulating properties. Besides, Z1 SEM analysis observed homogenously and compacted HPC microstructure at 250 and 500 °C. Doi: 10.28991/cej-2021-03091634 Full Text: PD

Effect of Changing Properties of Wythes in Precast Structural Sandwich Panels

This study investigates the effects of changing in the properties of face and core wythes in structural sandwich panels (with dimensions of 500 500 mm and 120 mm total height). Concrete face wythes of three grades (80, 70, 37) MPa, thicknesses of (25, 35, and 45) mm, and three types of core materials (high density foam, polyethylene foam, and palm bark) were used in the production of panels. Steel shear connectors were installed in the panels with angle of 45º. Three-point bending load test was carried out on all panels and results were compared with both of the theoretical extremes capacities of non- composite and fully-composite states and ANSYS software results. The degree of composite action (%) and the (strength/weight) ratio were the main parameters that judged the specimens. It was found that upgrading concrete increased overall strength of slabs especially in high strength concrete (80 MPa), however the use of lightweight concrete (70 MPa) caused high (strength/weight) ratio due to very lightweight. Results revealed that decreasing thickness of concrete face wythes had a positive effect on strength/weight ratio (although the ultimate loads decreased) that enhanced the performance of panels as lightweight structural panels. The optimum face wythe thickness is that of 2.5 cm and has high (strength/weight) ratio. It was noticed that adding polyethylene foam as a core material results in positive effect and high (strength/weight) ratio. Results revealed that high strength concrete (80 MPa) and light-weight concrete (37 MPa) are very successful in the production face wythes of precast light-weight sandwich panels that can obtain high (strength/weight) ratio and high percent of composite action

Omani Students’ Application of the Second Standard for Technology Coaches in Internship Program

The aim of this study was to investigate the extent to which Omani students apply In- ternational Society for Technology in Education (ISTE) second standard for technology coaches and its relation with gender, training institution type, student’s specialization, GPA and cohort. A questionnaire of twenty three items to measure the components of the second standard was derived from these components and used. A sample of 171 students was used to collect data. Onsite supervisors were used to evaluate students’ application of the second standard. The re- sults indicate that the overall performance of the students reflects a reasonable and acceptable performance but does not reach the target and desirable performance. Statistical analysis shows no significant differences due to gender, and cohort but there were significant differences due to students’ specialization, institution type and students’ GPA. The study concludes with some recommendations to improve the weak components and revise the procedures and processes of the internship progra

Weak-Key Analysis of POET

We evaluate the security of the recently proposed authenticated encryption scheme POET with regard to weak keys when its universal hash functions are instantiated with finite field multiplications. We give explicit constructions for weak key classes not covered by POET\u27s weak key testing strategy, and demonstrate how to leverage them to obtain universal forgeries

Impact of the underlying cause and co-morbid conditions on the outcome of hepatic encephalopathy

Background: Hepatic encephalopathy (HE) is a serious neuropsychiatric complication of acute and chronic liver diseases. This study aimed at identifying liver diseases and co-morbidity conditions associated with hepatic encephalopathy (HE) and their impact on patient`s mortality (the outcome).Methods: A hospital-based, prospective study enrolled 76 patients admitted with HE conducted at Ibn Sina specialized gastroenterology hospital, Sudan, from January 2010 to May 2011. Personal data, clinical presentation, underlying liver disease, precipitants, co-morbid conditions and the outcome of HE were obtained from the inpatients’ hospital records.Results: A total of 76 patients were included, 62 males (81.5%) and 14 females (18.5%) aged between 13 and 84 years old. Hepatitis B virus (HBV) was the most common cause of the liver disease (36.8%), followed by HCV (11.8%). Clinically, 53 patients (69%) had impaired level of consciousness. Infection was the most common risk factor for HE (54%) followed by electrolyte disturbance (42%). Overall mortality within one to three weeks following the admission was (50%). The higher percentage of mortality was seen inpatients with late stage autoimmune hepatitis, followed by HCC and in co-morbid conditions like renal impairment (58.8%).Conclusion: HE is associated with a high mortality despite proper management in specialized hospitals. The mortality tends to increase in the presence of comorbid condition.