96 research outputs found
Use of Computer Simulation to Reduce the Energy Consumption in a Tall Office Building in Dubai-UAE
Buildings are a major consumer of energy and thus have a significant impact on the environment. The use of artificial lights is a major contributor to the energy usage in a typical office building using electricity to run the lights and also increasing the cooling load due to its heat dissipation. Proper design for the maximization of natural light helps reduce the use of artificial lights and results in reduction in the buildings energy consumption. Computer simulation of the lighting and energy consumption in a typical tall office building in Dubai-UAE is used to optimize the effectiveness of natural lighting penetration and calculate the associated energy savings. Two alternative building designs are proposed and tested. The overall energy savings for the whole building reached 31.4 % for the proposed oval shaped design. This represents a significant reduction in the buildings electricity load and thus its impact on the environment
Epidemiology of herpes simplex virus type 2 in sub-Saharan Africa:systematic review, meta-analyses, and meta-regressions
Background: Herpes simplex virus type 2 (HSV-2) infection is a prevalent, sexually transmitted infection with a sizable disease burden that is highest in sub-Saharan Africa. This study aimed to characterize HSV-2 epidemiology in this region. Methods: Cochrane and PRISMA guidelines were followed to systematically review, synthesize, and report HSV-2 related findings up to August 23, 2020. Meta-analyses and meta-regressions were conducted. Findings: From 218 relevant publications, 451 overall outcome measures and 869 stratified measures were extracted. Pooled incidence rates ranged between 2.4–19.4 per 100 person-years across populations. Pooled seroprevalence was lowest at 37.3% (95% confidence interval (CI): 34.9–39.7%) in general populations and high in female sex workers and HIV-positive individuals at 62.5% (95% CI: 54.8–70.0%) and 71.3% (95% CI: 66.5–75.9%), respectively. In general populations, pooled seroprevalence increased steadily with age. Compared to women, men had a lower seroprevalence with an adjusted risk ratio (ARR) of 0.61 (95% CI: 0.56–0.67). Seroprevalence has decreased in recent decades with an ARR of 0.98 (95% CI: 0.97–0.99) per year. Seroprevalence was highest in Eastern and Southern Africa. Pooled HSV-2 proportion in genital ulcer disease was 50.7% (95% CI: 44.7–56.8%) and in genital herpes it was 97.3% (95% CI: 84.4–100%). Interpretation: Seroprevalence is declining by 2% per year, but a third of the population is infected. Age and geography play profound roles in HSV-2 epidemiology. Temporal declines and geographic distribution of HSV-2 seroprevalence mirror that of HIV prevalence, suggesting sexual risk behavior has been declining for three decades. HSV-2 is the etiological cause of half of genital ulcer disease and nearly all genital herpes cases with limited role for HSV-1. Funding: This work was supported by pilot funding from the Biomedical Research Program at Weill Cornell Medicine in Qatar and by the Qatar National Research Fund [NPRP 9–040–3–008]
Medical students' perceptions of supporting pharmacology learning in english by key information prepared in arabic
We explored medical students' perceptions of supporting pharmacology self-learning in English by focused materials prepared in Arabic. This study targeted third-year medical students at the Arabian Gulf University in Bahrain (n= 183). During the endocrine and metabolism subunit, which is taught in English, slides containing focused information in Arabic preceded detailed English ones. At the end of the subunit, students' perceptions were explored by a questionnaire and focus group discussions. Most participants reported that this intervention made pharmacology learning easier, improved confidence in drug selection, knowledge of adverse drug reactions, detection of response to medications and occurrence of adverse reactions. Most respondents thought that this intervention would help them during the clinical phase of their study and in communicating drug therapy to patients in Arabic. Supporting pharmacology learning in a foreign language with instructional materials prepared in a native language improved students self-reported learning and satisfaction.Scopu
Measuring medical students' professional competencies in a problem-based curriculum: A reliability study
Identification and assessment of professional competencies for medical students is challenging. We have recently developed an instrument for assessing the essential professional competencies for medical students in Problem-Based Learning (PBL) programs by PBL tutors. This study aims to evaluate the reliability and validity of professional competency scores of medical students using this instrument in PBL tutorials. Methods: Each group of seven to eight students in PBL tutorials (Year 2, n = 46) were assessed independently by two faculty members. Each tutor assessed students in his/her group every five weeks on four occasions. The instrument consists of ten items, which measure three main competency domains: interpersonal, cognitive and professional behavior. Each item is scored using a five-point Likert scale (1 = poor, 5 = exceptional). Reliability of professional competencies scores was calculated using G-theory with raters nested in occasions. Furthermore, criterion-related validity was measured by testing the correlations with students' scores in written examination. Results: The overall generalizability coefficient (G) of the professional competency scores was 0.80. Students' professional competencies scores (universe scores) accounted for 27% of the total variance across all score comparisons. The variance due to occasions accounted for 10%, while the student-occasion interaction was zero. The variance due to raters to occasions represented 8% of the total variance, and the remaining 55% of the variance was due to unexplained sources of error. The highest reliability measured was the interpersonal domain (G = 0.84) and the lowest reliability was the professional behavior domain (G = 0.76). Results from the decision (D) study suggested that an adequate dependability (G = 0.71) can be achieved by using one rater for five occasions. Furthermore, there was a positive correlation between the written examination scores and cognitive competencies scores (r = 0.46, P < 0.01), but not with the other two competency domains (interpersonal and professionalism). Conclusions: This study demonstrates that professional competency assessment scores of medical students in PBL tutorials have an acceptable reliability. Further studies for validating the instrument are required before using it for summative evaluation of students by PBL tutors.Scopu
Measuring medical students' professional competencies in a problem-based curriculum: A reliability study
Background: Identification and assessment of professional competencies for medical students is challenging. We
have recently developed an instrument for assessing the essential professional competencies for medical students
in Problem-Based Learning (PBL) programs by PBL tutors. This study aims to evaluate the reliability and validity of
professional competency scores of medical students using this instrument in PBL tutorials.
Methods: Each group of seven to eight students in PBL tutorials (Year 2, n = 46) were assessed independently by
two faculty members. Each tutor assessed students in his/her group every five weeks on four occasions. The
instrument consists of ten items, which measure three main competency domains: interpersonal, cognitive and
professional behavior. Each item is scored using a five-point Likert scale (1 = poor, 5 = exceptional). Reliability of
professional competencies scores was calculated using G-theory with raters nested in occasions. Furthermore,
criterion-related validity was measured by testing the correlations with students’ scores in written examination.
Results: The overall generalizability coefficient (G) of the professional competency scores was 0.80. Students’
professional competencies scores (universe scores) accounted for 27% of the total variance across all score
comparisons. The variance due to occasions accounted for 10%, while the student-occasion interaction was zero.
The variance due to raters to occasions represented 8% of the total variance, and the remaining 55% of the
variance was due to unexplained sources of error. The highest reliability measured was the interpersonal domain
(G = 0.84) and the lowest reliability was the professional behavior domain (G = 0.76). Results from the decision (D)
study suggested that an adequate dependability (G = 0.71) can be achieved by using one rater for five occasions.
Furthermore, there was a positive correlation between the written examination scores and cognitive competencies
scores (r = 0.46, P < 0.01), but not with the other two competency domains (interpersonal and professionalism).
Conclusions: This study demonstrates that professional competency assessment scores of medical students in PBL
tutorials have an acceptable reliability. Further studies for validating the instrument are required before using it for
summative evaluation of students by PBL tutors
A one-year cost–utility analysis of REBOA versus RTACC for non-compressible torso haemorrhage
Introduction: Major trauma is a leading cause of death and disability in young adults, especially from massive noncompressible torso haemorrhage. The standard technique to control distal haemorrhage and maximise central perfusion is resuscitative thoracotomy with aortic cross-clamping (RTACC). More recently, the minimally invasive technique of resuscitative endovascular balloon occlusion of the aorta (REBOA) has been developed to similarly limit distal haemorrhage without the morbidity of thoracotomy; cost–utility studies on this intervention, however, are still lacking. The aim of this study was to perform a one-year cost–utility analysis of REBOA as an intervention for patients with major traumatic non-compressible abdominal haemorrhage, compared to RTACC within the U.K.’s National Health Service. Methods: A retrospective analysis of the outcomes following REBOA and RTACC was conducted based on the published literature of survival and complication rates after intervention. Utility was obtained from studies that used the EQ5D index and from self-conducted surveys. Costs were calculated using 2016/2017 National Health Service tariff data and supplemented from further literature. A cost–utility analysis was then conducted. Results: A total of 12 studies for REBOA and 20 studies for RTACC were included. The mean injury severity scores for RTACC and REBOA were 34 and 39, and mean probability of death was 9.7 and 54%, respectively. The incremental costeffectiveness ratio of REBOA when compared to RTACC was £44,617.44 per quality-adjusted life year. The incremental cost-effectiveness ratio, by exceeding the National Institute for Health and Clinical Effectiveness’s willingness-to-pay threshold of £30,000/quality-adjusted life year, suggests that this intervention is not cost-effective in comparison to RTACC. However, REBOA yielded a 157% improvement in utility with a comparatively small cost increase of 31.5%. Conclusion: Although REBOA has not been found to be cost-effective when compared to RTACC, ultimately, clinical experience and expertise should be the main factor in driving the decision over which intervention to prioritise in the emergency context
Preparing foundation-year students for medical studies in a problem-based learning environment:Students' perceptions
Purpose: To contribute to the field of preparing new students for their medical studies and to investigate how foundation-year medical students perceive the progression of appropriate learning skills for studying in a PBL medical curriculum via the support of a course aiming at facilitating students with these skills.
Methods: A 10-point scale online questionnaire consisting of 20 questions was used for data collection. 50 out of the 59 (19 males and 31 females) students responded and self-evaluated a list of learning skills according to the course objectives before and after the course. Cronbach׳s alpha was used to test for internal consistency and reliability of the collected data and Principal Component Exploratory Factor Analysis was performed. Paired t-test was used to examine differences between pre- and post-analysis data.
Results: The internal consistency of the questionnaire was sufficient. Factor analysis identified four factors: 1) Ability to search for, share, and present information, 2) Ability to develop learning tools and express opinions, 3) Ability to use diverse learning sources, and 4) Ability to participate in discussion and reflect. Overall improvement between pre- and post-test was high (2.38). Paired t-tests showed significant improvements (p<.001) for each of the 4 factors. The four factors together explained 60.7% percent of variance in the data.
Discussion: Students reported large improvements among learning skills required in a problem-based medical curriculum, and suggests that students in a premedical foundation year can benefit from a course aiming at preparing students for their future learning in a PBL environment. A shortcoming was considered the retrospective nature of the pretest, possibly biasing the results of the comparisons
Refurbishment of public housing villas in the United Arab Emirates (UAE): energy and economic impact
© 2016, Springer Science+Business Media Dordrecht. This study aims at assessing the technical and economic benefits of refurbishing existing public housing villas in the UAE. Four representative federal public housing villas built between 1980s and 2010s were modeled and analyzed. The Integrated Environmental Solutions-Virtual Environment (IES-VE) energy modeling software was used to estimate the energy consumption and savings due to different refurbishment configurations applied to the villas. The refurbishment technical configurations were based on the UAE’s Estidama green buildings sustainability assessment system. The refurbishment configurations include upgrading three elements: the wall and roof insulation as well as replacing the glazing. The annual electricity savings results indicated that the most cost-efficient refurbishment strategy is upgrading of wall insulation (savings up to 20.8 %) followed by upgrading the roof’s insulation (savings up to 11.6 %) and lastly replacing the glazing (savings up to 3.2 %). When all three elements were refurbished simultaneously, savings up to 36.7 % were achieved (villa model 670). The savings translated to CO2 emission reduction of 22.6 t/year. The simple and discounted payback periods for the different configurations tested ranged between 8 and 28 and 10 and 50 years, respectively
Diagnostic value of endobronchial ultrasound-guided transbronchial needle aspiration in various lung diseases
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