33 research outputs found
The relationship between lifestyle and the frequency of polycystic ovary syndrome in Saudi female residing in Riyadh
Background: Polycystic Ovary Disorder (PCOS) is perceived as the most widely recognized endocrinopathy in reproductive women. This study aimed to assess the relationship between the lifestyle and frequency of polycystic ovary syndrome in Saudi Arabia.Methods: This is a case-control study conducted on females at princess Nourah University (PNU), King Fahad Medical City (KFMC) and malls in Riyadh city, Saudi Arabia. The study included females in the reproductive age including 401 controls and 122 PCOS cases.Results: History of pregnancy related disorders was higher among the PCOS women in comparison to controls, while abortion represented the highest percentage in both cases and controls. Family history of polycystic ovary syndrome was doubled in cases than controls. There was significant increase in the percentage of hypothyroidism and hyperlipidemia in polycystic ovary syndrome patients (P <0.001). Snoring, use of oral contraceptives, high prolactin level, incidence of menorrhagia and urinary tract infection were significantly higher in cases than controls (P <0.001). In addition, there was no difference between controls and polycystic ovary syndrome cases regarding their dietary intake. On the other hand, physical activity was significantly higher in controls compared to polycystic ovary syndrome group.Conclusions: This study supports previous studies that revealed a relation between polycystic ovary syndrome and endocrinological disorders such as hypothyroidism, hyperprolactinemia, and obesity. On the other hand, there is no relation between dietary intake and PCOS, however exercising regularly can decrease the possibility of having the disease
Predicting the drying shrinkage behavior of high strength portland cement mortar under the combined influence of fine aggregate and steel micro fiber
Medical students' perceptions of complementary and alternative medicine therapies: A pre- and post-exposure survey in Majmaah University, Saudi Arabia
Background: Evidently, Complementary and Alternative Medicine (CAM) is increasingly a recognized medical practice that efficiently uses multiple treatment therapies and techniques in promoting the health and wellbeing of people as well as preventing and managing a variety of human disorders. Research in CAM, which courses exposure to diverse healthcare professionals, is important from many perspectives including improvement in teaching skills of faculty, enhancing capacity building, and innovative curriculum development. This pre- and post-design crosssectional study aimed to assess perceptions, training needs, personal usage, use in office practice, and knowledge of two batches of medical students toward CAM therapies in Majmaah University, Saudi Arabia.Materials and Methods: The second year medical students of the first (year 2012-13) and second (year 2013-2014) batch [n=26 & 39, respectively] were selected for this study. A reliable 16-item self-administered questionnaire was distributed among all students for answering before and after the 48-hour specific 19 CAM therapies course, in terms of CAM therapies are clearly conventional or alternative, training needs, effectiveness, personal use, use in practice, management of two clinical cases by CAM or conventional therapies, and views about which evidence based approach strongly support individual CAM modalities.Results: Medical students' knowledge and perceptions of CAM therapies significantly improved across some sub-items of CAM questionnaire with a positive trend in the rest of its items including their views about CAM therapies, need for further training, personal use of therapies and advising patients regarding CAM practices strongly supported by randomized clinical controlled trials and published case studies.Conclusion: CAM course tends to have positive impact on the knowledge and perceptions of medical students, in addition to need for further training, and personal use and use of CAM therapies in practice in line with strong evidence-based data regarding therapeutic efficacy. The preliminary results of this study call for further research in specific CAM modalities with a larger sample in academic settings across the nation. Key words: Medical students; Complementary and Alternative Medicine; CAM course; CAM therapies; pre-post design study; Saudi Arabia
MEDICAL STUDENTS' PERCEPTIONS OF COMPLEMENTARY AND ALTERNATIVE MEDICINE THERAPIES: A PRE- AND POST-EXPOSURE SURVEY IN MAJMAAH UNIVERSITY, SAUDI ARABIA
Background: Evidently, Complementary and Alternative Medicine (CAM) is increasingly a recognized medical practice that efficiently uses
multiple treatment therapies and techniques in promoting the health and wellbeing of people as well as preventing and managing a variety of
human disorders. Research in CAM, which courses exposure to diverse healthcare professionals, is important from many perspectives including
improvement in teaching skills of faculty, enhancing capacity building, and innovative curriculum development. This pre- and post-design crosssectional
study aimed to assess perceptions, training needs, personal usage, use in office practice, and knowledge of two batches of medical
students toward CAM therapies in Majmaah University, Saudi Arabia.
Materials and Methods: The second year medical students of the first (year 2012-13) and second (year 2013-2014) batch [n=26 & 39,
respectively] were selected for this study. A reliable 16-item self-administered questionnaire was distributed among all students for answering
before and after the 48-hour specific 19 CAM therapies course, in terms of CAM therapies are clearly conventional or alternative, training needs,
effectiveness, personal use, use in practice, management of two clinical cases by CAM or conventional therapies, and views about which
evidence based approach strongly support individual CAM modalities.
Results: Medical students' knowledge and perceptions of CAM therapies significantly improved across some sub-items of CAM questionnaire
with a positive trend in the rest of its items including their views about CAM therapies, need for further training, personal use of therapies and
advising patients regarding CAM practices strongly supported by randomized clinical controlled trials and published case studies.
Conclusion: CAM course tends to have positive impact on the knowledge and perceptions of medical students, in addition to need for further
training, and personal use and use of CAM therapies in practice in line with strong evidence-based data regarding therapeutic efficacy. The
preliminary results of this study call for further research in specific CAM modalities with a larger sample in academic settings across the nation
Seroprevalence of antibodies to SARS-CoV-2 among blood donors in the early month of the pandemic in Saudi Arabia
Background: Serologic testing provides better understanding of SARS-CoV-2 prevalence and its transmission. This study was an investigation of the prevalence of antibodies to SARS-CoV-2 among blood donors in Saudi Arabia.
Objective: To estimate the seroprevalence of anti-SARS-CoV-2 antibodies among blood donors in Saudi Arabia during the early phase of the COVID-19 pandemic.
Methods: Serology results and epidemiological data were analyzed for 837 adult blood donors, with no confirmed SARS-CoV-2 infection, in Saudi Arabia from 20th to 25th May 2020. Seroprevalence was determined using electrochemical immunoassay to detect anti-SARS-CoV-2 antibodies.
Results: The overall seroprevalence of anti-SARS-CoV-2 antibodies was 1.4% (12/837). Non-citizens had higher seroprevalence compared with citizens (OR 13.6, p = 0.001). Secondary education was significantly associated with higher seroprevalence compared with higher education (OR 6.8, p = 0.005). The data showed that the highest seroprevalence was in Makkah (8.1%). Uisng Makkah seroprevalence as the reference, the seroprevalence in other areas was: Madinah 4.1% (OR 0.48, 95% CI 0.12-1.94), Jeddah 2.3% (OR 0.27, 95% CI 0.31-2.25), and Qassim 2.9 % (OR 0.34, 95% CI 0.04-2.89) and these were not statistically different from seroprevalence in the Makkah region.
Conclusions: At the early months of the COVID-19 pandemic in Saudi Arabia, the seroprevalence of antibodies to SARS-CoV-2 among blood donors was low, but was higher among non-citizens. These findings may indicate that non-citizens and less educated individuals may be less attentive to preventive measures. Monitoring seroprevalence trends over time require repeated sampling
Seroprevalence of SARS-CoV-2 (COVID-19) among Healthcare Workers in Saudi Arabia: Comparing Case and Control Hospitals
Healthcare workers (HCWs) stand at the frontline for fighting coronavirus disease 2019 (COVID-19) pandemic. This puts them at higher risk of acquiring the infection than other individuals in the community. Defining immunity status among health care workers is therefore of interest since it helps to mitigate the exposure risk. This study was conducted between May 20th and 30th, 2020. Eighty-five hospitals across Kingdom of Saudi Arabia were divided into 2 groups: COVID-19 referral hospitals are those to which RT-PCR-confirmed COVID-19 patients were admitted or referred for management (Case-hospitals). COVID-19 nonaffected hospitals where no COVID-19 patients had been admitted or managed and no HCW outbreak (Control hospitals). Next, seroprevalence of severe acute respiratory syndrome coronavirus 2 among HCWs was evaluated; there were 12,621 HCWs from the 85 hospitals. There were 61 case-hospitals with 9379 (74.3%) observations, and 24 control-hospitals with 3242 (25.7%) observations. The overall positivity rate by the immunoassay was 299 (2.36%) with a significant difference between the case-hospital (2.9%) and the control-group (0.8%) (P value <0.001). There was a wide variation in the positivity rate between regions and/or cities in Saudi Arabia, ranging from 0% to 6.31%. Of the serology positive samples, 100 samples were further tested using the SAS2pp neutralization assay; 92 (92%) samples showed neutralization activity.
The seropositivity rate in Kingdom of Saudi Arabia is low and varies across different regions with higher positivity in case-hospitals than control-hospitals. The lack of neutralizing antibodies (NAb) in 8% of the tested samples could mean that assay is a more sensitive assay or that neutralization assay has a lower detection limits; or possibly that some samples had cross-reaction to spike protein of other coronaviruses in the assay, but these were not specific to neutralize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)
Investigating Crack Initiation and Propagation of Concrete in Restrained Shrinkage Circular/Elliptical Ring Test
The restrained ring test, which is recommended by AASHTO and ASTM, has been used for assessing the potential of early-age cracking of concrete and other cement-based materials. Recently, a novel elliptical ring test method has been proposed to replace the circular ring test method for the purpose of shortening ring test duration and observing crack initiation and propagation more conveniently. In order to explore the mechanism of this novel test method, a numerical model is developed to analyze crack initiation and propagation process in restrained concrete rings, in which the effect of concrete shrinkage is simulated by a fictitious temperature drop applied on concrete causing the same strain as that induced by shrinkage. First, an elastic analysis is conducted to obtain the circumferential stress contour of a concrete ring subject to restrained shrinkage. Combined with the fictitious crack model, a fracture mechanics method is introduced to determine crack initiation and propagation, in which crack resistance caused by cohesive force acting on fracture process zone is considered. Finite element analysis is carried out to simulate the evolution of stress intensity factor in
restrained concrete rings subject to circumferential drying. Cracking age and position of a series of
circular/elliptical concrete rings are obtained from numerical analyses which agree reasonably well with
experimental results. It is found that the sudden drop of steel strain observed in the restrained ring test
represents the onset of unstable crack propagation rather than crack initiation. The results given by the
AASHTO/ASTM restrained ring test actually reflects the response of a concrete ring as a structure to
external stimulation, in this case restrained concrete shrinkage.The financial support from the National Natural Science Foundation of China under the grants of NSFC
51478083 & 51421064, Engineering and Physical Sciences Research Council under the grant of EP/I031952/1, and the National Basic Research Program of China (973 Program, Grant No. 2015CB057703) is gratefully acknowledged
Prediction of Drying Shrinkage of Portland Cement Paste: Influence of Shrinkage Mechanisms
Ultimate drying shrinkage of paste was investigated in terms of the Gibbs-Bangham shrinkage and the capillary stress mechanisms. Shrinkage measurements and nitrogen sorption isotherms were obtained on cement pastes of water-to-cement (W/C) ratios of 0.4,0.6 and 0.75. The contribution to ultimate drying shrinkage from these two mechanisms was obtained from ultimate shrinkage versus increase in surface free energy curves in the relative humidity (RH) range of 95 to 0 percent. The Gibbs-Bangham stress mechanism is the major contributor to shrinkage stresses in this RH range. The capillary stress mechanism is active in the RH range of 95 to 50 percent.The maximum Gibbs-Bangham stress shrinkage, which occurs at 0 percent RH, is linearly proportional to total surface area as obtained from volume-thickness (V-t) sorption analysis. Maximum capillary stress shrinkage occurs at about 50 percent RH. This component was found to be linearly proportional to cumulative capillary surface area. V-t adsorption analysis was used to estimate the cumulative capillary surface area. The equations for predicting maximum Gibbs-Bangham and capillary stress shrinkage were extended to include effect of RH of drying. They were tested on different shrinkage results of well-hyd-rated pastes of 0.4 and 0.6 W/C ratios and found to be accurate
The Prediction of Drying Shrinkage of Portland Cement Paste and Concrete.
The effects of specimen size and geometry on drying shrinkage of paste, mortar and concrete were investigated. Drying shrinkage-weight loss curves showed that ultimate shrinkage is independent of member size and shape Development of drying shrinkage over time can be accurately described using a modified Ross equation. It includes a shrinkage-half time coefficient which is linearly proportional to the volume-to-surface (V/S) ratio on a semilogarithmic scale. The equation was tested on long-term shrinkage measurements and found to be accurate for concretes of V/S ratios up to 4.2 in. and drying times later than about 30 days. The equation can be used with a single shrinkage measurement at 30 days or later to predict ultimate shrinkage. The predicted error using this approach was within (+OR-)20 percent of the measured shrinkage. This is a substantial improvement over current ACI procedures which have prediction errors of about (+OR-)63 percent. A constitutive model for predicting ultimate drying shrinkage was tested. It showed excellent agreement with experimental results of different sizes and shapes of paste, mortar and concrete. The effects of water-to-cement (W/C) ratio, curing time, and aggregate content on drying shrinkage versus relative humidity (RH) in the range of 0 to 100 percent were investigated. A relative humidity correction factor was developed in the range of 11 to 100 percent RH which is independent of W/C ratio, curing time, and aggregate content. The present findings suggest that ACI procedures may overestimate shrinkage in the RH range of 40 to 100 percent. Ultimate drying shrinkage of paste was modeled in terms of the Gibbs-Bangham and the capillary stress shrinkage mechanisms. These two mechanisms were described by two different relationships which incorporate nitrogen surface areas. The proposed equations were tested on shrinkage results obtained from the literature on well-hydrated pastes and found to be accurate.Ph.D.Civil engineeringUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/161198/1/8702673.pd