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A simplified shear-moment interaction model is proposed for the shear capacity of reinforced concrete (RC) beams without web reinforcement, considering four basic variables (longitudinal steel ratio, concrete strength, shear span to depth ratio and beam size) and verified by existing experimental results. The proposed model shows that shear strength and mode of failure depend on the shear-moment paths followed to bring the beams to failure. This study shows that the variations in the experimental results of shear capacity of slender RC beams ( a / d  2.5 ) defined at the formation of diagonal cracks of beams under the combined action of moment and shear can primarily be explained by the variations of the concrete tensile strength. A design formula based on this shear-moment interaction model is also proposed for shear capacity of slender RC beams. [ABSTRACT FROM AUTHOR]

Background: diabetes is well studied in Saudi Arabia; however, there seems to be little research in the area of awareness, education and health care delivery. Objectives: to assess the awareness about diabetes mellitus among attendees of primary health care centers, Makkah, Saudi Arabia. Subjects and Methods: a cross-sectional study was conducted among a representative random sample of adult attendees of primary health care centers (diabetic and non-diabetics), Makkah Al-Mokkaramah, the kingdom of Saudi Arabia during the study period (1-31 November, 2016). An Arabic self-administered questionnaire was used for data collection. It includes 31 questions with sections of demographic data, community awareness regarding diabetes definition, risk factors, signs and symptoms, and complications community awareness regarding diabetes prevention. Results: the study included 662 adult patients. Approximately one-third of them (32.2%) aged 60 years or more. Females represent 51.1% of them. More than one-fifth of them (21%) were university graduated whereas 6.3% were illiterates. Prevalence of diabetes among the participants was 33.7% and majority of them (97.9%) had family history of diabetes. The most frequent sources were mass media (57.4%), health sector (29.9%) and educational sector (10.6%). Overall sufficient awareness regarding diabetes mellitus was reported among majority of the participants (91.2%). Among studied factors, only marital status and income were significantly associated with sufficient awareness. Conclusion: population in Makkah AL-Mokkaramah has enough knowledge of the general knowledge of diabetes regarding risk factors, symptoms, etc. However, they are not very well aware of the diabetes associated secondary complications. [ABSTRACT FROM AUTHOR]

This study evaluates the shear capacity of reinforced concrete (RC) membrane elements subjected to pure inplane shear stresses at different levels of loading. These elements are shown to fail in four different modes. A model is proposed for the shear capacity of these membrane elements that can be computed by direct simple expressions without the need to any iterative process as is usually the case in existing models. Failure in these membrane elements is generally preceded by the formation of two or more major critical cracks assumed herein to propagate in a direction normal to the principal tensile stresses in the concrete. At each stage of loading, the major critical cracks are shown to open at an optimum angle that corresponds to the least shearing resistance to external loading. Major cracks as well as ultimate shear capacity of RC membrane elements are shown to occur when the contribution of the x-reinforcement to resist shear stresses is equal to that of the y-reinforcement. Experimental results of tests on RC membrane elements subjected to pure inplane shear stresses obtained from literature are used to validate and compare the proposed model with existing models. Examples are provided for the computations of shear capacity by the proposed model for the different modes of failure. [ABSTRACT FROM AUTHOR]

A simplified model is proposed for the shear strength of reinforced concrete (RC) membrane elements subjected to in-plane normal and shear stresses. The shear strength of these elements is evaluated at various stages of loading and can be computed by direct simple expressions. Failure in these elements is shown to occur in four different modes and to be preceded by the formation of two or more major critical cracks. At each stage of loading, the major critical cracks are shown to open at an optimum angle that supplies least shearing resistance to external loading. Consequently, these major cracks are shown to form when the contribution of the reinforcement in the x -direction to resist shear stresses is equal to that of the reinforcement in the y -direction. A unique normalized relationship is derived for the shear strength as a function of a ratio defined in terms of the amounts and yield strengths of reinforcements. Experimental results of 70 RC membrane elements subjected to in-plane normal and shear stresses obtained from literature are used to validate the proposed model. Numerical examples are provided for the computations of shear strength and modes of failure by the proposed model. [ABSTRACT FROM AUTHOR]

The active and passive lateral earth pressures against retaining walls under seismic loading are investigated, taking into consideration the variations of internal friction angle ∅ and seismic effect represented by the seismic angle ϑ. This study basically involves the computation of the active and passive lateral earth pressure coefficients, ae kae and kpe, and their coefficients of variation, cov(kae and) cov(kpe, using a first order Taylor's series expansion. The concept of extreme value distributions (maxima and minima) is utilized for evaluating the reliability of these earth pressure coefficients. Design charts are developed for a wide range of granular soils. Examples illustrating the design method based on the usage of the reliability of these coefficients are also presented. Values of load factor utilized in the conventional deterministic approach are correlated with reliability levels; the load factor values vary depending on the importance of the structure and the variations of the design input values as contrasted to the constant value of load factor used in the conventional deterministic approach. [ABSTRACT FROM AUTHOR]

Abstract: The SRS method explicitly relates the coefficient of consolidation c v and end of primary (EOP) settlement δ p to the intercept and slope of the linear section of the observed dδ t /dt – δ t curve that can theoretically be recognized for the average degree of consolidation U ≥52.6%. The SRS method calculates the coefficient of consolidation independently of any specific value of U and can simultaneously compute the EOP settlement δ p without the need to continue the test into the secondary compression range. Thus, the overall testing time may significantly be reduced and the influence of load duration as well as secondary compression may be minimized. Results of oedometer tests on four clayey soils are used to compare the SRS method with existing methods such as the Casagrande and Taylor methods. [ABSTRACT FROM AUTHOR]

Background: Slums or informal settlements characterize most large cities in LMIC. Previous evidence suggests pharmacies may be the most frequently used source of primary care in LMICs but that pharmacy services are of variable quality. However, evidence on pharmacy use and availability is very limited for slum populations.Methods: We conducted household, individual, and healthcare provider surveys and qualitative observations on pharmacies and pharmacy use in seven slum sites in four countries (Nigeria, Kenya, Pakistan, and Bangladesh). All pharmacies and up to 1200 households in each site were sampled. Adults and children were surveyed about their use of healthcare services and pharmacies were observed and their services, equipment, and stock documented.Results: We completed 7692 household and 7451 individual adults, 2633 individual child surveys, and 157 surveys of pharmacies located within the seven sites. Visit rates to pharmacies and drug sellers varied from 0.1 (Nigeria) to 3.0 (Bangladesh) visits per person-year, almost all of which were for new conditions. We found highly variable conditions in what constituted a "pharmacy" across the sites and most pharmacies did not employ a qualified pharmacist. Analgesics and antibiotics were widely available but other categories of medications, particularly those for chronic illness were often not available anywhere. The majority of pharmacies lacked basic equipment such as a thermometer and weighing scales.Conclusions: Pharmacies are locally and widely available to residents of slums. However, the conditions of the facilities and availability of medicines were poor and prices relatively high. Pharmacies may represent a large untapped resource to improving access to primary care for the urban poor. [ABSTRACT FROM AUTHOR]

Background: A good social environment is a key strategy to improve the level of education and achievement in medical college students. However, survey data from Jeddah, Saudi Arabia have indicated that a large number of medical students are affected negatively by their social status. This article comparatively explores the impact of four main factors: Social class/Background, Students' Personality, Health Status, and Psychological health on their achievement. Data were collected as part of a program of qualitative and quantitative research investigating the prevalence of bad environment effect on the psychological level of the students. Objectives: To study the four main factors Social class/Background, Students' Personality, Health Status, and Psychological health affecting academic achievement among Female Students at Ibn Sina National College. Methods: The study was conducted among 1315 female students attending colleges of Ibn Sina-Jeddah-Saudi Arabia between 1st of April - 31th of May 2016. An open-ended questionnaire was developed to cover the objectives. Conclusion: After assessment of the factors and variables across the targeted sites about the academic achievement were often conclude that overall achievement were very good regardless the factor. [ABSTRACT FROM AUTHOR]

Background: In Kenya, cardiovascular diseases (CVDs) accounted for more than 10% of total deaths and 4% of total Disability-Adjusted Life Years (DALYs) in 2015 with a steady increase over the past decade. The main objective of this paper was to review the existing policies and their content in relation to prevention, control and management of CVDs at primary health care (PHC) level in Kenya.Methods: A targeted document search in Google engine using keywords "Kenya national policy on cardiovascular diseases" and "Kenya national policy on non-communicable diseases (NCDs)" was conducted in addition to key informant interviews with Kenyan policy makers. Relevant regional and international policy documents were also included. The contents of documents identified were reviewed to assess how well they aligned with global health policies on CVD prevention, control and management. Thematic content analysis of the key informant interviews was also conducted to supplement the document reviews.Results: A total of 17 documents were reviewed and three key informants interviewed. Besides the Tobacco Control Act (2007), all policy documents for CVD prevention, control and management were developed after 2013. The national policies were preceded by global initiatives and guidelines and were similar in content with the global policies. The Kenya health policy (2014-2030), The Kenya Health Sector Strategic and Investment Plan (2014-2018) and the Kenya National Strategy for the Prevention and Control of Non-communicable diseases (2015-2020) had strategies on NCDs including CVDs. Other policy documents for behavioral risk factors (The Tobacco Control Act 2007, Alcoholic Drinks Control (Licensing) Regulations (2010)) were available. The National Nutrition Action Plan (2012-2017) was available as a draft. Although Kenya has a tiered health care system comprising primary healthcare, integration of CVD prevention and control at PHC level was not explicitly mentioned in the policy documents.Conclusion: This review revealed important gaps in the policy environment for prevention, control and management of CVDs in PHC settings in Kenya. There is need to continuously engage the ministry of health and other sectors to prioritize inclusion of CVD services in PHC. [ABSTRACT FROM AUTHOR]