An investigation of the computer training needs of the teachers and students at teacher colleges in Saudi Arabia

Worldwide discussion has been initiated about the role of computers and information technology in schools. In Saudi Arabia, the introduction of computers into education institutes has been a feature of development planning since 1990, but many educationalists assert that the technology is underestimated and blame inadequate teacher preparation.The main purpose of this study was to investigate the computer experience, computer knowledge, computer training needs and attitude toward computers of Teacher College teaching staff and students in Saudi Arabia. It also examines the availability of human and physical resources for appropriate training in this area.The survey sample was 147 teaching staff and 472 students drawn from all departments and levels of study in five men's Teacher Colleges, one from each of the five regions of the country. In addition, a small number of policy- makers (e. g. college deans and ministry officials) were interviewed.Data were collected via a questionnaire survey, using an instrument adapted from Fodah (1990), containing multiple- choice questions on computer experience, knowledge and training needs, and a 5- part Likert-type attitude scale. Information on computer courses, resources and related policy were addressed by semi-structured interviews. Lack of access to computers, deficiencies in computer knowledge and low computer experience were found among staff and students. Lack of computer training appears to be one of the main causes of low utilization; inadequate material and human resources are another obstacle. Nevertheless, both groups had positive attitudes to computers.If Saudi Arabia is to keep abreast of the information revolution, Teacher Colleges need a high level of equipment and service infrastructure, and well-prepared computer teachers and staff capable of training their colleagues and students to integrate computers in teaching and learning

A Numerical Simulation of the Effect of Ambient Temperature on Capillary Tube Performance in Domestic Split Air Conditioners with R22 Alternatives

A numerical model has been formulated to simulate the capillary tube insplit air conditioners of 1 and 2 TR capacities under high outdoor air temperatures. The outdoor air temperature was varied from 35 to 55°C with 5 °Cincrements. Three environment friendly refrigerantswereused as alternatives to R22. They are  R290, R407C and R410A. Finite difference method has been adopted in conjunction with EES software. This model is capable of predicting pressure, temperature, quality, velocityandviscositydistributions through the capillary tube for all refrigerants. The geometrical parameters and input conditions to the capillary tube model areextracted from experimental data.  Theseinclude inner diameter, mass flow rate, surface roughness, temperature and pressure of the subcooledliquid refrigerant.  Theresults show that the capillary choking length increases with increasing outdoor air temperature.    Results of the simulation show thatR290 needsmore capillary length than the other refrigerants investigated,whereas  R410A needs less capillary tube length. Keywords: Capillary tube simulation; capillary tube with R22,R290, R407C, R410A; high ambient effect on capillary tube

An efficient sensor based on anodic activation of graphene oxide for sensitive and selective determination of dopamine in blood serum

A native graphene oxide (NGO) prepared by Hummers modified method was used as the template materials for the fabrication of electrochemically oxidative graphene oxide (OGO) onto a glassy carbon electrode (GCE). The fabrication of OGO-GCE persuaded via anodic reversible potentiodynamic of NGO base surface materials that increases the concentration of oxygen functionalities. The development of a new aldehyde/alcoholic functional group on OGO-GCE characterized by XPS analysis is a marked signal for oxygen richness surface which provoked on the cost of sp2 hybridized function. The EIS data underline that OGO-GCE promote the electron transfer kinetics much more than NGO-GCE by 9 times as estimated by the rate constant calculation. The XPS and EIS data highlight the influence of anodic treatment on increasing the interlayer spacing distance between the resultant OGO. Differential pulse voltammetry (DPV) results were evident for a promising efficiency of OGO-GCE on the simultaneous determination of dopamine (DA), ascorbic acid (AA) and uric acid (UA). In addition, the selectivity of the proposed sensor for DA quantification in the presence of high concentrations of AA and UA was achieved successfully with a detection limit (DL3s) approach to 12 nM. The analytical performance of OGO-GCE on serum blood revealed its potential application for trace DA quantification

Immunohistochemical study of breast cancer antigens (part 1)

Survivin has been characterized as a member of the family of inhibitor of apoptosis proteins (lAP). It is a 16.5 kD protein made up of 142 amino acids. Survivin is expressed in the G2/M phase of the cell cycle. It has been previously sho\vn to be expressed in a large number of cancers, and its expression has been associated with the aggression of tumors, or with the poor survival of cancer patients

Performance Evaluation of Small Scale Air-Conditioning System Using R22 and Alternative Refrigerants

A mathematical model has been formulated to predict the influence of high outdoor air temperature on the performance of small scale air - conditioning system using R22 and alternative refrigerants R290, R407C, R410A. All refrigerants were investigated in the cooling mode operation. The mathematical model results have been validated with experimental data extracted from split type air conditioner of 2 TR capacity. This entailed the construction of an experimental test rig which consists of four main parts. They are, the refrigeration system, psychrometric test facility, measuring instrumentation, and auxiliary systems. The conditioned air was maintained at 25 0C dry bulb and 19 0C wet bulb for all tests. The outdoor ambient air temperature was varied from 35 0C to 55 0C in 5 0C increments. The study showed that R290 is the better replacement for R22 when the air conditioning system works under high ambient temperature. It has better performance as a drop in refrigerant. R407C has the closest performance to R22, followed by R410A

EXPERIMENTAL INVESTIGATION OF INDIVIDUAL EVACUATED TUBE HEAT PIPE SOLAR WATER HEATING SYSTEMS

lar water heating systems with heat pipes of three diameter groups of 16, 22 and 28.5 mm. The first and third groups had evaporator lengths of 1150, 1300 and 1550 mm. The second group had an additional length of 1800 mm. all heat pipes were of fixed condenser length of 200 mm. Ethanol at 50% fill charge ratio of the evaporator volume was used as the heat pipes working fluid. Each heat pipe condenser section was inserted in a storage tank and the evaporator section inserted into an evacuated glass tube of the Owens- Illinois type. The combined heat pipe and evacuated glass tube form an active solar collector of a unique design. The resulting ten solar water heating systems were tested outdoors under the meteorological conditions of Baghdad, Iraq. Experiments were carried out with no load, intermittent and continuous load conditions. Some tests, at no load, were carried out with and without reflectors. The overall system efficiency was found to improve with load conditions by a maximum of 55%. The system employing an 1800 mm evaporator length and 22 mm heat pipe (HP7) showed the best performance by higher water temperatures, overall useful energy gain and efficiency at various load conditions. System performance was predicted theoretically using electrical analogy derived from an energy balance. An agreement of within 14% was obtained between theoretical and experimental values

Spatial Binding Impairments in Visual Working Memory following Temporal Lobectomy

Disorders of the medial temporal lobe (MTL) adversely affect visual working memory (vWM) performance, including feature binding. It is unclear whether these impairments generalize across visual dimensions or are specifically spatial. To address this issue, we compared performance in two tasks of 13 epilepsy patients, who had undergone a temporal lobectomy, and 15 healthy controls. In the vWM task, participants recalled the color of one of two polygons, previously displayed side by side. At recall, a location or shape probe identified the target. In the perceptual task, participants estimated the centroid of three visible disks. Patients recalled the target color less accurately than healthy controls because they frequently swapped the nontarget with the target color. Moreover, healthy controls and right temporal lobectomy patients made more swap errors following shape than space probes. Left temporal lobectomy patients, showed the opposite pattern of errors instead. Patients and controls performed similarly in the perceptual task. We conclude that left MTL damage impairs spatial binding in vWM, and that this impairment does not reflect a perceptual or attentional deficit

Identification of biomarkers in ductal carcinoma in situ of the breast with microinvasion

<p>Abstract</p> <p>Background</p> <p>Widespread use of mammography in breast cancer screening has led to the identification of increasing numbers of patients with ductal carcinoma <it>in situ </it>(DCIS). DCIS of the breast with an area of focal invasion 1 mm or less in diameter is defined as DCIS with microinvasion, DCIS-Mi. Identification of biological differences between DCIS and DCIS-Mi may aid in understanding of the nature and causes of the progression of DCIS to invasiveness.</p> <p>Methods</p> <p>In this study, using resected breast cancer tissues, we compared pure DCIS (52 cases) and DCIS-Mi (28 cases) with regard to pathological findings of intraductal lesions, biological factors, apoptosis-related protein expression, and proliferative capacity through the use of immunohistochemistry and the TdT-mediated dUTP-biotin nick end labeling (TUNEL) method.</p> <p>Results</p> <p>There were no differences in biological factors between DCIS and DCIS-Mi, with respect to levels of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor type 2. The frequency of necrosis and positive expression ratio of survivin and Bax were significantly higher in DCIS-Mi than in DCIS. In addition, apoptotic index, Ki-67 index, and positive Bcl-2 immunolabeling tended to be higher in DCIS-Mi than in DCIS. Multivariate analysis revealed that the presence of necrosis and positive survivin expression were independent factors associated with invasion.</p> <p>Conclusion</p> <p>Compared with DCIS, DCIS-Mi is characterized by a slightly elevated cell proliferation capacity and enhanced apoptosis within the intraductal lesion, both of which are thought to promote the formation of cell necrotic foci. Furthermore, the differential expression of survivin may serve in deciding the response to therapy and may have some prognostic significance.</p

Characterisation of male breast cancer: a descriptive biomarker study from a large patient series

Male breast cancer (MBC) is rare. We assembled 446 MBCs on tissue microarrays and assessed clinicopathological information, together with data from 15 published studies, totalling 1984 cases. By immunohistochemistry we investigated 14 biomarkers (ERα, ERβ1, ERβ2, ERβ5, PR, AR, Bcl-2, HER2, p53, E-cadherin, Ki67, survivin, prolactin, FOXA1) for survival impact. The main histological subtype in our cohort and combined analyses was ductal (81%, 83%), grade 2; (40%, 44%), respectively. Cases were predominantly ERα (84%, 82%) and PR positive (74%, 71%), respectively, with HER2 expression being infrequent (2%, 10%), respectively. In our cohort, advanced age (>67) was the strongest predictor of overall (OS) and disease free survival (DFS) (p = 0.00001; p = 0.01, respectively). Node positivity negatively impacted DFS (p = 0.04). FOXA1 p = 0.005) and AR p = 0.009) were both positively prognostic for DFS, remaining upon multivariate analysis. Network analysis showed ERα, AR and FOXA1 significantly correlated. In summary, the principle phenotype of MBC was luminal A, ductal, grade 2. In ERα+ MBC, only AR had prognostic significance, suggesting AR blockade could be employed therapeutically

Bcl-2 expression and clinico-pathological correlations in invasive ductal carcinoma of the breast

Bcl-2 is an anti-apoptotic protein belonging to a family of proteins that act as regulators of apoptosis in mammalian cells. Bcl-2 expression has previously been reported in normal breast ductal cells and its involvement in the hormonal regulation of hyperplasia and involution was further suggested, and it was thought to be expressed through hormonedependent pathways. Bcl-2 is a cytoplasmic oncoprotein which is highly expressed in human solid tumours. In breast cancer cells, however, Bcl-2 expression is down regulated, the exact mechanism and the effects of which are not clearly defined, as bcl-2 expression appears to be inversely correlated with the presence of p53 mutations. This work aimed at investigating the expression of bcl-2 in invasive ductal carcinoma of the breast utilizing an immunohistochemistry assay as well as studying the clinical correlations of bcl-2. Bcl-2 was detected in 43.7% of 382 invasive ductal carcinoma study cases. Its expression correlated positively, with lower age of patients, higher histological grades, large tumour sizes, estrogen receptor positivity and progesterone receptor negativity. However, the statistical correlations were weak. With the data obtained, it was found that the expression of bcl-2 correlated with unfavourable prognoses. Furthermore, bcl-2 detection alone may not be very helpful in consolidating a clinical diagnosis