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Use of Learning Portals in Education in the Arab Region
No full textWith the advancement of Internet and World Wide Web the definition of business, entertainment and education has changed in astonishing ways. In late 1990s web portals opened a new arena for organizations because the use of portals has enabled content providers to make information from various sources accessible to their employees or customers with varying interests. Nowadays we have a variety of portals available offering different services like public services, health services, educational services as well as media and entertainment. In this paper our focus is on the portals providing services in educational context called the Learning Portals.AAC
Direct UPLC-MS-MS Validated Method for the Quantification of 5-Aminolevulinic Acid: Application to in-vitro Assessment of Colonic-Targeted Oral Tablets
No full textA reliable, sensitive, specific, and rapid ultra-performance liquid chromatography-tandem mass spectrometric (UPLC-MS-MS) method was developed for the determination of 5-aminolevulinic acid (5-ALA) in orally-administered colonic delivery system. The prepared system is a compression-coated tablet using granulated chitosan as the coat layer. L-Tyrosine (TYR) was used as an internal standard with no need for derivatization. The chromatographic system consisted of Acquity UPLC BEH C18 column and isocratic mobile phase composed of acetonitrile and 0.1% formic acid with a flow rate of 2.5 min. The assay was based on ESI+ mode in a multiple reaction monitoring (MRM) transitions at m/z 132.08 > 86.0 and m/z 132.08 > 114.0 and m/z 182.1 > 91.2 for 5-ALA and TYR, respectively. Limit of quantification was 5.0 ng/mL and the calibration curve was linear (r(2) = 0.994). Within-run precision and between-run repeatability were expressed as relative standard deviation and were lower than 2.5%. The recoveries from control samples were > 95%. The method was successfully applied for evaluation in assay and release profile of 5-ALA colon targeted tablets media containing suspended rat cecal contents pH 6.8 medium (colonic) for colonic delivery
Effect of Long-Term Dietary Lipids on Femur Mineral Content, Ex vivo Prostaglandin E2 release and Bone Growth in Growing Rabbits
No full textThe long-term effects of different dietary oil sources with varying omega-6/omega-3 (-6/-3) polyunsaturated fatty acids (PUFAs) ratios on the bone marrow fatty acids level, bone growth, and ex vivo prostaglandin E2 (PGE2) release and minerals content in bone were evaluated in rabbits. Weanling male and female New Zealand White rabbits were randomly assigned to five groups and fed ad libitum on diets containing 70 g/kg of added oil for 100 days as follow: soybean oil (SBO control), sesame oil (SO), fish oil (FO), DHA algae oil (DHA), and DHA and ARA algae oils (DHA/ARA). The dietary lipid treatments were formulated to provide the following ratio of -6/-3 fatty acids: 8.7 (SBO), 21.8 (SO), 0.4 (FO), 0.6 (DHA), and 0.7 (DHA/ARA). The bone marrow fatty acids level of rabbits was significantly influenced by and reflected the dietary level of -6 and -3 fatty acids fed to rabbits. Rabbits fed the FO diet maintained a lower -6/-3 ratio and a higher EPA and DHA concentrations in their bone marrow; those fed the SO diet maintained a higher -6/-3 fatty acids ratio, while those fed the SBO diet maintained a higher LA and ALA concentrations and intermediate value of -6/-3 ratio. Ex vivo PGE2 level declined progressively as the -6/-3 dietary ratio declined. There was a significant main effect of dietary treatment on femur Ca, P, Mg, and Zn contents in both genders. These results demonstrate that dietary -6/-3 ratio modulates bone PGE2 production in growing rabbits, hence may reduce bone resorption and improve bone mass during growth. In addition, the significant elevation in mineral content and the maintenance of optimal Ca/P ratio in bone of DHA/ARA and DHA fed groups demonstrates that marine algae oils may be promising dietary sources for promoting bone mineralization and formation thus improving bone mass during the growth stage.KACST & R
OntoQue: A Question Generation Engine for Educational Assessment Based on Domain Ontologies
No full textAssessment forms a key constituent of the instructional process. It provides a measure for evaluating learning and evaluating the effectiveness of instructional pedagogy. However, constructing assessment items for objective tests is a challenging task, which is time consuming and requires experience. This paper describes the OntoQue system, an engine for objective assessment item generation based on domain ontologies. Ontologies are knowledge representation structures which provide a conceptual model of the domain. The engine uses knowledge inherent in the ontology about domain entities such as classes, properties, and individuals to generate semantically correct assessment items. We present the design, implementation and evaluation of the Onto Que engine. The system was evaluated using four OWL ontologies from different domains. Results of the evaluation show that %90 of assessment items generated by OntoQue are categorized as "good"
Heuristic Techniques for Solving the Vehicle Routing Problem with Time Windows
No full textSolving the Vehicle Routing Problem (VRP) and its related variants is at the heart of scientific research for optimizing logistic planning. One important variant of the VRP is the Vehicle Routing Problem with Time Windows (VRPTW), where it is assumed that a number of clients must be served by a fleet of vehicles operating from a central depot. Solving this problem requires finding a set of minimum cost routes for the vehicles, while observing a number of pre-defined problem constraints. Since the VRPTW is NP-hard, solving it using exact methods is very time consuming. Heuristic and meta-heuristic approaches are usually the preferred option for solving practical size problems. In this paper, we describe the problem and explain some of the most popular heuristic techniques that have been applied for the solution construction and the solution improvement phases of the problem.Singapore Institute of Electronics and International Association of Computer Science and Information Technolog
Saudi nursing student’s perception of effective clinical instructors’ characteristics
No full textThe clinical experience has been recognized as a significant and very essential component of nursing education. Clinical instructors have a responsibility not only to their students but also to clients and the nursing profession to identify and exhibit effective clinical teacher characteristics. Moreover, as the clinical experiences and its resources are limited, students must optimize clinical practice opportunities; they must therefore, work with effective clinical instructors.
The purpose of this study is to determine the characteristics of effective clinical instructors as perceived by Saudi nursing students.
The Nursing Clinical Teacher Effective Inventory (NCTEI) developed a 48-item Likert scale checklist describing discrete teachers characteristics clustered into five subscales or categories: teaching ability, nursing competence, personality traits, interpersonal relationships and evaluation.
300 Saudi female nursing students, enrolled in the 4th to 8th term of their study in different colleges of nursing will be asked to participate. This sample also includes students from the college of health sciences, who are enrolled in the second term, of the first year, till those in the second term of the third year.College of Nursing, King Saud Universit
Biharmonic extensions on trees without positive potentials
No full textLet be a tree rooted at endowed with a nearest-neighbor transition probability that yields a recurrent random walk. We show that there exists a function biharmonic off whose Laplacian has potential theoretic importance and, in addition, has the following property: Any functiononwhich is biharmonic outside a finite set has a representation, unique up to addition of a harmonic function. We obtain a characterization of the functions biharmonic outside a finite set whose Laplacian has 0 flux similar to one that holds for a function biharmonic outside a compact set in Rfor= 23, and 4 proved by Bajunaid and Anandam. Moreover, we extend the definition of flux and, under certain restrictions on the tree, we characterize the functions Biharmonic outside a finite set that have finite flux in this extended sense.the research center of the center for female scientific and medical colleges in King Saud Universit
Can lung volumes and capacities be used as an outcome measure for phrenic nerve recovery after cardiac surgeries?
No full textAbstract
Phrenic nerve is the main nerve drive to the diaphragm and its injury is a well-known complication following cardiac surgeries. It results in diaphragmatic dysfunction with reduction in lung volumes and capacities. This study aimed to evaluate the objectivity of lung volumes and capacities as an outcome measure for the prognosis of phrenic nerve recovery after cardiac surgeries. In this prospective experimental study, patients were recruited from Cardio-Thoracic Surgery Department, Educational-Hospital of College of Medicine, Cairo University. They were 11 patients with right phrenic nerve injury and 14 patients with left injury. On the basis of receiving low-level laser irradiation, they were divided into irradiated group and non-irradiated group. Measures of phrenic nerve latency, lung volumes and capacities were taken pre and post-operative and at 3-months follow up. After 3 months of low-level laser therapy, the irradiated group showed marked improvement in the phrenic nerve recovery. On the other hand, vital capacity and forced expiratory volume in the first second were the only lung capacity and volume that showed improvement consequent with the recovery of right phrenic nerve (P value <0.001 for both). Furthermore, forced vital capacity was the single lung capacity that showed significant statistical improvement in patients with recovered left phrenic nerve injury (P value <0.001). Study concluded that lung volumes and capacities cannot be used as an objective outcome measure for recovery of phrenic nerve injury after cardiac surgeries
Preparation and Characterization of Chitosan Microparticles for Oral Sustained Delivery of Gliclazide: In Vitro/In Vivo Evaluation
No full textChitosan microparticles were prepared with tripolyphosphate (TPP) by ionic cross-linking with gliclazide (GLZ) as a model drug. The particle sizes of TPP-chitosan microparticles ranged from 675-887 mu m with loading efficiencies of greater than 94%. Chitosan concentration, TPP solution pH, and glutaraldehyde volume solution added to the TPP cross-linking solution affected drug release characteristics. Pectin interactions with cationic chitosan on the surface of TPP/chitosan microparticles led to the formation of polyelectrolyte complex films that improved drug sustained release performance. In vivo testing of the GLZ-chitosan microparticles in diabetic albino rabbits demonstrated a significant antidiabetic effect of GLZ/chitosan microparticles after 8 h that lasts for 18 h compared with GLZ powder that produced a maximal hypoglycemic effect at 4 h, suggesting that GLZ/chitosan microparticles represent an improved system for the long-term delivery of GLZKing Saud Universit
In vitro mass production of Ruta gravoelens L. for secondary products
No full textHypocotyls explants of 1-week-old Ruta gravoelens L. seedlings showed high regeneration ability on Murashige and Skoog’s medium supplemented with 5.2 mM H2PO4 -, 250 mM adenine sulphate, 3.0% sucrose and 8.87 lM BA. Increasing phosphate and adenine sulphate concentrations had pronounced effects on organogenesis and shoot growth compared to the stander MS medium. Multiple shoots were successfully maintained for 60 days in static liquid medium without any hyperhydricity phenomena. Uncountable shoot buds and shoots were developed on the leaf surface which was in contact with the medium. The growth index increased linearly during the culture course (R2 = 0.992–0.999) and the highest GI (30.43) was achieved on medium enriched with 90 mM nitrogen and 4.5% sucrose. Medium supplemented with 6.0% sucrose and 60 mM N yielded the highest biomass (4.37 g per flask). However, medium with the stander N content and 6.0% sucrose developed the maximum percentage of biomass (6.67%). The highest percentage of furanocoumarins (11.46 mg g-1 dry weight) calculated as xanthotoxin was produced in medium enriched with 90 mM N and 4.5 or 6.0% sucrose, whereas the maximum rutin (73.5 mg g-1 dry weight) was on medium supplemented with 90 mM N and 4.5% sucrose. Developing system seems to be used for secondary metabolites production because the shoot rooting did not appear. So, all energy is devoted for shoots multiplication, their growth and secondary metabolites production.King Saud Universit