The Relation between Cultural Learning Framework and Blackboard System Acceptance: Case Study Blended Learning University-United Arab Emirate

Many Electronic learning (E-learning) universities have recently appeared. Students of these universities are from various cultures, and need different requirements in their studies. This study covers the Arabic learner’ needs and requirements, through examines the relationship between cultural learning framework and system acceptance using Collaboration Blackboard System in online learning environment. This study used a survey to evaluate this relation using represented sample of blended learning university students in United Arab Emirate. The result shows that culture has a significant relation with acceptance in learning framework using Blackboard System. This relation between culture and acceptance differ according to cultural dimensions that have been considered in this study. Keywords: Culture, Technology Acceptance Model (TAM), Blackboard System

Artificial Neural Network Controller for Reducing the Total Harmonic Distortion (THD) in HVDC

A neural network based space vector modulation (SVM) of voltage source inverter is proposed. The voltage source converter (VSC) is highly used in high voltage direct current (HVDC) transmission so that a detailed analysis and transmission of this system is carried out. In addition, a non-linear neural network controller is proposed to control the space vector pulse width modulation (SVPWM) to reduce the total harmonic distortion (THD) of the converter (inverter) output voltage. The inverter outputcurrent is analyzed with two switching frequency 1050Hz and1450Hz with and without proposed ANN controller. The results show a THD enhancement about 0.74 % for 1050Hz and 0.68 % for 1450Hz

The Effect of Proper Selection of Drilling Fluid on Drilling Operation in Janbour Field

Selecting a proper drilling fluid has always been a difficult task to overcome by drilling mud engineers. There are some constraints such as formation lithology encountered, the range of temperature and pressure of the formation, environmental considerations and cost that play a paramount role in the selection of the proper drilling fluid. In this paper, well data from Janbour Oilfield was used and analyzed. The concentration lies on the second section of the well since it shows to be the most problematic one.  Salt saturated mud was designed in lab and compared with the mud used to drill the second section of the well. The final result of this paper indicates that the designed salt saturated mud is superior to the mud used to drill the section.

Prognostic factors associated with failure of total elbow arthroplasty

AimsThe aims of this study were to identify and evaluate the current literature examining the prognostic factors which are associated with failure of total elbow arthroplasty (TEA).MethodsElectronic literature searches were conducted using MEDLINE, Embase, PubMed, and Cochrane. All studies reporting prognostic estimates for factors associated with the revision of a primary TEA were included. The risk of bias was assessed using the Quality In Prognosis Studies (QUIPS) tool, and the quality of evidence was assessed using the modified Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) framework. Due to low quality of theevidence and the heterogeneous nature of the studies, a narrative synthesis was used.ResultsA total of 19 studies met the inclusion criteria, investigating 28 possible prognostic factors. Most QUIPS domains (84%) were rated as moderate to high risk of bias. The quality of the evidence was low or very low for all prognostic factors. In low-quality evidence, prognostic factors with consistent associations with failure of TEA in more than one study were: the sequelae of trauma leading to TEA, either independently or combined with acute trauma, and male sex. Severalother studies investigating sex reported no association. The evidence for other factors was of very low quality and mostly involved exploratory studies.ConclusionThe current evidence investigating the prognostic factors associated with failure of TEA is of low or very low quality, and studies generally have a moderate to high risk of bias. Prognostic factors are subject to uncertainty, should be interpreted with caution, and are of little clinical value. Higher-quality evidence is required to determine robust prognostic factors for failure of TEA

Assessment of the Carbonate Rocks of the Pila Spi Formation for Cement Industry, in Permam Mountain, Erbil, Iraqi Kurdistan Region

The Pila Spi Formation is exposed in Permam Mountain forming its carapace, and continuous ridges for few hundreds of kilometers. The rocks of the formation are mainly dolomitic limestone, dolomite, and limestone with various proportions. The thickness of the formation in Permam Mountain is about 100 m. Nine samples are collected from the Pila Spi Formation along a recently road cut across Permam Mountain. The sampling interval varies from 10 to 15 m. The collected samples were subjected to X-ray fluorescence (XRF) spectroscopy test to indicate the percentages of the main oxides in the samples. The results showed that the chemical composition of samples No. 1 and 9 meet the Iraqi standards for cement industry, whereas the remaining samples (Nos. 2–8) do not meet the Iraqi standards, and their total thickness is 80 m. To evaluate the suitability of the exposed rocks for cement industry in the sampled section within the Pila Spi Formation, different ratios of sample No. 1 were mixed with different ratios of a sample called sample No. A, it represents a mixture of samples No. 2–8. The mixing ratios are: (Sample No. 1/sample No. A) 50/50, 60/40, 70/30, 80/20, and 90/10. The same procedure was repeated for Sample No. 9. Another attempt was performed by mixing equal ratios of samples Nos. 1 and 9 with the same performed ratios with sample No. A.The chemical compositions of the samples were indicated using XRF test. The results showed that the best mixing ratios for the cement industry are 90:10, 80:20, and 70: 30 (samples Nos. 1+9: sample No. A)

Cross-Effects in Microgravity Flows

Film growth by chemical/physical vapor deposition is a process of considerable interest in microgravity experiments. The absence of natural convection should allow better control of film growth processes but, in highly non-isothermal ampoules, thermal slip (creep) can become a matter of significant concern. The reported research is a theoretical and experimental investigation of the flow of gas/vapor mixtures under non-continuum conditions. The Boltzmann equation has been solved for a monatomic gas under non-condensing conditions and the various phenomenological coefficients have been computed. Computations for realistic potentials as well as for velocity and creep slip have been completed and the creep slip has been found to be dependent on the type of gas confirming the accuracy of previous variational results. The variational technique has been extended and planar flows calculated via the Burnett solutions. Velocity, diffusion and creep slips have been computed for gas mixtures and previously unknown dependencies of the creep slip on the mixture properties have been observed. Also for gas mixtures, an integral representation of the linearized Boltzmann operator has been developed for use in numerical and variational calculations for all intermolecular force laws. Two, two-bulb capillary systems have been designed, built and tested for the measurements of cross-flows; one of glass for isothermal measurements and one of stainless steel for non-isothermal measurements. Extensive data have been collected for Ar-He and N2-He mixtures at a variety of pressures and mole ratios. Viscosity, velocity slip coefficients and tangential momentum accommodation coefficients have been obtained from measurements with a spinning rotor gauge via a new theory that has been formulated for the spinning rotor gauge in the slip regime. The FIDAP fluid dynamics code has been applied to condensing flows in ampoules in the continuum regime and agreement obtained with the earlier work of Duval

Characterization and Control of the Microbial Community Affiliated with Copper or Aluminum Heat Exchangers of HVAC Systems

Microbial growth in heating ventilation and air-conditioning (HVAC) systems with the subsequent contamination of indoor air is of increasing concern. Microbes and the subsequent biofilms grow easily within heat exchangers. A comparative study where heat exchangers fabricated from antimicrobial copper were evaluated for their ability to limit microbial growth was conducted using a full-scale HVAC system under conditions of normal flow rates using single-pass outside air. Resident bacterial and fungal populations were quantitatively assessed by removing triplicate sets of coupons from each exchanger commencing the fourth week after their installation for the next 30 weeks. The intrinsic biofilm associated with each coupon was extracted and characterized using selective and differential media. The predominant organisms isolated from aluminum exchangers were species of Methylobacterium of which at least three colony morphologies and 11 distinct PFGE patterns we found; of the few bacteria isolated from the copper exchangers, the majority were species of Bacillus. The concentrations and type of bacteria recovered from the control, aluminum, exchangers were found to be dependent on the type of plating media used and were 11,411–47,257 CFU cm−2 per coupon surface. The concentration of fungi was found to average 378 CFU cm−2. Significantly lower concentrations of bacteria, 3 CFU cm−2, and fungi, 1 CFU cm−2, were recovered from copper exchangers regardless of the plating media used. Commonly used aluminum heat exchangers developed stable, mixed, bacterial/fungal biofilms in excess of 47,000 organisms per cm2 within 4 weeks of operation, whereas the antimicrobial properties of metallic copper were able to limit the microbial load affiliated with the copper heat exchangers to levels 99.97 % lower during the same time period

Dimethyl fumarate in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial

Dimethyl fumarate (DMF) inhibits inflammasome-mediated inflammation and has been proposed as a treatment for patients hospitalised with COVID-19. This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing multiple treatments in patients hospitalised for COVID-19 (NCT04381936, ISRCTN50189673). In this assessment of DMF performed at 27 UK hospitals, adults were randomly allocated (1:1) to either usual standard of care alone or usual standard of care plus DMF. The primary outcome was clinical status on day 5 measured on a seven-point ordinal scale. Secondary outcomes were time to sustained improvement in clinical status, time to discharge, day 5 peripheral blood oxygenation, day 5 C-reactive protein, and improvement in day 10 clinical status. Between 2 March 2021 and 18 November 2021, 713 patients were enroled in the DMF evaluation, of whom 356 were randomly allocated to receive usual care plus DMF, and 357 to usual care alone. 95% of patients received corticosteroids as part of routine care. There was no evidence of a beneficial effect of DMF on clinical status at day 5 (common odds ratio of unfavourable outcome 1.12; 95% CI 0.86-1.47; p = 0.40). There was no significant effect of DMF on any secondary outcome

Dimethyl fumarate in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial

Dimethyl fumarate (DMF) inhibits inflammasome-mediated inflammation and has been proposed as a treatment for patients hospitalised with COVID-19. This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing multiple treatments in patients hospitalised for COVID-19 (NCT04381936, ISRCTN50189673). In this assessment of DMF performed at 27 UK hospitals, adults were randomly allocated (1:1) to either usual standard of care alone or usual standard of care plus DMF. The primary outcome was clinical status on day 5 measured on a seven-point ordinal scale. Secondary outcomes were time to sustained improvement in clinical status, time to discharge, day 5 peripheral blood oxygenation, day 5 C-reactive protein, and improvement in day 10 clinical status. Between 2 March 2021 and 18 November 2021, 713 patients were enroled in the DMF evaluation, of whom 356 were randomly allocated to receive usual care plus DMF, and 357 to usual care alone. 95% of patients received corticosteroids as part of routine care. There was no evidence of a beneficial effect of DMF on clinical status at day 5 (common odds ratio of unfavourable outcome 1.12; 95% CI 0.86-1.47; p = 0.40). There was no significant effect of DMF on any secondary outcome