EVALUATION OF THERMAL SRESSES IN CONTINOUOS CONCRETE BRIDGES

This search is mainly concerned with making a comparison between three methods for analyzing continuous concrete bridges, Priestly, Abdul-Ahad and finite elements. Three standard Design temperature distribution, New Zealand, AASHTO and British (5400) were used to analyze the concrete bridges in Baghdad. The analysis of two continues precast prestressed concrete bridges in Baghdad are presented. Another comparison as made between the thermal stresses and the stress associated with dead and live loads. Analytical results indicated that stresses and curvature values are very sensitive to the type of temperature distribution assumed. The suggested analytical models for the bridge can be used to be predict thermal movement and stresses due to any shape of temperature distribution

Study of the effect of HFE gene mutations on iron overload in Egyptian thalassemia patients

Background: HFE gene mutations have been shown to be responsible for hereditaryhemochromatosis. Their effect on iron load in β-thalassemia patients and carriers remains controversial.Objectives: We aimed to determine the prevalence of HFE gene mutations (C282Y and H63D) in β-thalassemia patients and carriers and to investigate its effect on their serum ferritin levels.Patients and methods: A total of 100 β-thalassemia subjects; 75 patients and 25 carriers were screened for HFE gene mutations by PCR-RFLP. Serum ferritin measured by ELISA was evaluated in relation to HFE mutations.Results: Twenty-eight β-thalassemia patients (37.3%) were heterozygotes for H63D mutation (H/D), 8 (10.7%) were D/D and 39 (52%) were negative (H/H). Among carriers, 4 (16%) were D/D and 21 (84%) were H/H homozygotes. C282Y mutant allele was not detected in any of the subjects. Serum ferritin levels were significantly higher in β-thalassemia patients heterozygotes or homozygotes for H63D mutation compared to those without mutation (p= 0.000). Carriers homozygotes for H63D mutation showed significantly higher serum ferritin levels compared to those without mutation (p< 0.001).Conclusion: Homozygosity for H63D mutation tends to be associated with higher ferritin levels in beta-thalassemia patients and carriers suggesting its modulating effect on iron load in these cases

Growing and laying performance of two different-plumage color Japanese quail varieties supplemented with corn silk in their diet

The current study aimed to investigate the dietary supplementation effect of corn silk (CS) on performance and blood chemistry of brown and whitefeathered quails during the grower and layer periods. Japanese quails of brown and white-feathered color (180 birds/variety at 2 wks old) were randomly allotted into three groups with 3 replicates each (n = 20 birds/ replicate). Corn silk powder (CS) was supplemented to the basal diet at 0, 1, and 2% of the diet for each quail variety for 1-month growing period, then continued for another 6-wk laying period to assess the egg production and egg quality characteristics. CS supplementation at 1% and 2% for brown and white-feathered quails respectively improved their growth performance (body weight and weight gain), carcass yield, and intestinal villi length with increasing feed consumption but without changes in feed conversion ratio. In both quail varieties, CS addition had a hypolipidemic effect, confirmed by lowering serum triglyceride (TG), cholesterol (CHO), and low density lipoprotein (LDL) while increased high density lipoprotein (HDL) concentrations (P < 0.05) with a clear response observed in white quails than the brown ones. Besides, CS supplementation increased (P = 0.002) hen day egg production in brown feathered quails, while reducing it in the white-feathered quails compared with the CS-free diet. The increased egg production was not significantly (P > 0.05) correlated with lower content of TG and CHO, while significantly increased the antioxidant content in both quail varieties (P < 0.05). Moreover, CS dietary supplementation significantly enhanced (P = 0.003) the yolk color, especially in brown-feathered quail. In conclusion, CS can be safely supplemented to the Japanese quail diet (1% and 2% for brown-feathered and white-feathered quails respectively) to improve growth performance, and egg quality characteristics

Brain-based learning in design and visual arts education: a bibliometric assessment of Scopus indexed literature [version 3; peer review: 2 approved, 1 not approved]

Background: This study aims to critically review, quantify, and assess research outcomes on brain-based learning with an evidence-based study on Scopus indexed literature, with a focus to understand the evolution structure and growth, detect trends, subject development, and most importantly, identify the gaps in the published body of literature that relates brain-based learning to design and visual arts education. Methods: Various scientometric tools were used to map, visualize, and analyze 186 research publications, indexed in Scopus in a twenty-year timespan ‘2001-2021’. Annual publication trends, relevant sources, prolific authors, authorship patterns, productive organizations and countries, funding agencies, keyword co-occurrence analysis, and thematic evolution mapping on brain-based learning publications were examined in this study. Results: Despite the significance to apply brain-based learning strategies in design and visual arts education to boost students’ knowledge and creative skills, the findings show a decline in quantities and growth patterns in brain-based learning research directed towards design disciplines in the past twenty years. Among the identified (186) documents published in (128) sources, with (1013) citations, the study detected only (57) research (30%) that were related to ‘design education,’ including those focusing on ‘instructional design, ‘and ‘syllabus design’ whereas only (3) articles were in ‘design and visual arts’ disciplines. Conclusion: These rather small numbers reflect the big gap in the current body of literature that associates brain-based learning with creativity-based disciplines, specifically in design and visual arts education. This infers the necessity to direct the attention of academics, researchers, and educationalists in the fields of design and arts towards brain-based learning applications, research and pedagogy

Advanced Analysis Techniques for Intra-cardiac Flow Evaluation from 4D Flow MRI

Time-resolved 3D velocity-encoded MR imaging with velocity encoding in three directions (4D Flow) has emerged as a novel MR acquisition technique providing detailed information on flow in the cardiovascular system. In contrast to other clinically available imaging techniques such as echo-Doppler, 4D Flow MRI provides the 3D Flow velocity field within a volumetric region of interest over the cardiac cycle. This work reviews the most recent advances in the development and application of dedicated image analysis techniques for the assessment of intra-cardiac flow features from 4D Flow MRI.Novel image analysis techniques have been developed for extraction of relevant intra-cardiac flow features from 4D Flow MRI, which have been successfully applied in various patient cohorts and volunteer studies. Disturbed flow patterns have been linked with valvular abnormalities and ventricular dysfunction. Recent technical advances have resulted in reduced scan times and improvements in image quality, increasing the potential clinical applicability of 4D Flow MRI.4D Flow MRI provides unique capabilities for 3D visualization and quantification of intra-cardiac blood flow. Contemporary knowledge on 4D Flow MRI shows promise for further exploration of the potential use of the technique in research and clinical applications

Impact of Age and Diastolic Function on Novel, 4D flow CMR Biomarkers of Left Ventricular Blood Flow Kinetic Energy

Two-dimensional (2D) methods of assessing mitral inflow velocities are pre-load dependent, limiting their reliability for evaluating diastolic function. Left ventricular (LV) blood flow kinetic energy (KE) derived from four-dimensional flow cardiovascular magnetic resonance imaging (4D flow CMR) may offer improvements. It remains unclear whether 4D LV blood flow KE parameters are associated with physiological factors, such as age when compared to 2D mitral inflow velocities. Fifty-three healthy volunteers underwent standard CMR, plus 4D flow acquisition. LV blood flow KE parameters demonstrated good reproducibility with mean coefficient of variation of 6 ± 2% and an accuracy of 99% with a precision of 97%. The LV blood flow KEiEDV E/A ratio demonstrated good association to the 2D mitral inflow E/A ratio (r = 0.77, P < 0.01), with both decreasing progressively with advancing age (P < 0.01). Furthermore, peak E-wave KEiEDV and A-wave KEiEDV displayed a stronger association to age than the corresponding 2D metrics, peak E-wave and A-wave velocity (r = −0.51 vs −0.17 and r = 0.65 vs 0.46). Peak E-wave KEiEDV decreases whilst peak A-wave KEiEDV increases with advancing age. This study presents values for various LV blood flow KE parameters in health, as well as demonstrating that they show stronger and independent correlations to age than standard diastolic metrics

Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10&nbsp;years; 78.2% included were male with a median age of 37&nbsp;years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020