1,107 research outputs found
Experimental Study for Load-Settlement Behavior of Flat and Shell Footings on Sandy Silt Soil
Shell foundations are often used to raise the carrying capacity of a structure on weak soils. In cases where large superstructure loads must be transferred to poorer soils, shell foundations are more cost-effective than ordinary shallow foundations. Advances in the study and design of shell-type foundations have shown their superiority over traditional footings in poorer soils. The current study aims to investigate shell shape’s influence on ultimate load capacity. Seven footing types’ models were created along with an appropriate testing box. The soil needed for the study was from the region north of Mosul city, classified as silt with low plasticity (sandy silt) soil. A laboratory model experimentally determined the ultimate load capacities for inverted and upright conical, inverted and upright pyramid, and hemispherical shell foundations on silty soil. The achieved results were associated with those for conventional flat squares and circles. According to the findings, the “upright conical” shell footing has a load capacity of 12.7 kN, higher than the other foundations, and its efficiency was 51%. When comparing foundations, the “upright pyramidal” shell footing has better settling characteristics and a settlement factor of 0.017. As the shell factor decreases, the shell foundation begins to behave more like a flat foundation, which reduces the maximum load capacity of the shell foundation
Improvement of Soft Soil Properties Using Dynamic Compaction with Stone Columns: Case Study (AL-Mualla Site-Yeman)
Dynamic compaction was considered as one of a deep compaction method which was used to improve the soil properties. Also it was used to save cost and time in comparison with other methods.The aims of the present studies were to study the improvement and changes in soil properties that occurred in Al-Mualla Site-Yeman using dynamic compaction. The site soils classified as Silty Sand with small boulder with Clayey-Silt layer extend from 2.2 m to 3.2 m deep.Cone penetration test was done before and after treatment process using dynamic compaction for approximately the same two tested boreholes. As a result of the treatment and based on how the soil properties changes, the soil was divided into three zones varied from (1.2 to 5, 5 to 8.6, and 8.6 to 11 m) respectively. Field results show that there was increased in bearing capacity from 80 kN/m2 to 110 kN/m2. Cone penetration test for the first zone increased from (1.2 to 8.35 MN/m2), and from (2.43 to 7.07 MN/m2) for the first and third zone respectively at the first tested borehole and also from (2.05 to 6.8 MN/m2), and (2.14 to 5.0 MN/m2) for the second tested borehole. Also can be noted that the cone penetration test results decreased from (5.22 to 3.77 MN/m2) for the second zone at the first tested borehole, with no change was happening for the second tested boreholes.Also the effect of soil improvement on the settlement value and effective stress distribution was studied theoretically using finite element package PLAXIS2D program. The result shows that the improvement in soil properties leads to decrease in the expected settlement
Nurturing Entrepreneurship Ecosystem in a Developing Economy: Myths and Realities
Entrepreneurship is considered as a panacea for economic infirmities. Development and prosperity can be fostered, upon the organized availability of the required resources, ambidextrously.  Entrepreneurship ecosystem is an appropriate approach where a systematic and conducive atmosphere for business activities is paved by providing support and services in the area of business policy, financing, human capital availability, infrastructure accessibility, entrepreneurial culture orientation and internationalization of indigenous products. However, despite having numerous entrepreneurship reinforce institutions, the entrepreneurship ecosystem of many developing countries is still sluggish, Pakistan is prominent among those. To improve entrepreneurship ecosystem, experts have endorsed the role of state ‘pivotal’. In this study, the entrepreneurship ecosystem of Pakistan is explored by focusing the role of government along other dimensions. For the purpose of this examination, an inductive approach was adopted in which twelve open ended interviews were conducted from policy makers, entrepreneurs, entrepreneurship professors and trade associations across the country. After thematic analysis, entrepreneurial ecosystem was found stagnant, where the role of government revealed as ambivalent, yet unfriendly and deficient. In order to develop entrepreneurship, a specific national policy for entrepreneurship should be enacted on priority and then ‘one size fit approach’ must be relinquished. Keywords: Entrepreneurship, Entrepreneurship Ecosystem, Small and Medium Enterprises, Developing Economy, SME
Stability Behavior of Lime Stabilized Gypseous Soil
In arid and semi-arid zones, gypsum (CaSO4.2H2O) is one of the soluble of the common minerals that found in soils. In Iraq, gypseous soils is a worldwide stability problem that causes extensive damage upon wetting, and occur in certain areas characterized by variation of climatic conditions. The results of the stability behavior of lime stabilized gypseous soil where present in this paper under different tests. These tests were erosion, leaching and soaking. Erosion test was conducted under different variables such as water temperature, water velocity and flow duration. The soil used in this study was taken from a site near Al – Hader district about (80 km) from Mosul city. Its main geotechnical index properties are liquid limit is (46%), plastic limit (22%) and specific gravity is 2.58. The amount of the gypsum was 20%. The soil samples were treated with optimum lime percent (4%) depending on the Illinois procedure. A gypseous soil with 20% gypsum content was used and stabilized with 4% lime. All stabilized soil samples were cured for 2 days at 490 C. The results indicate that, the loss in weight increased for samples subjected to the flowing water, further increase in weight losses with increasing flow duration. High water velocity causes increasing in weight losses and loss in gypsum content , more loss in weight and more loss in gypsum content, for all values of flow duration and water temperature. Unconfined compressive strength decreased during the soaking process and further decrease in strength with increasing soaking duration. The leaching effect causes a continuous increasing in the permeability value of unstabilized soil samples, while it has an insignificant effect on the permeability of lime stabilized soil samples. Leaching is a time-dependent process. The results showed that the pH values of natural and lime stabilized soil samples decreases during leaching process
An alternative surgical approach to subclavian and innominate stenosis: a case series
We report three cases of symptomatic stenosis of the great vessels or supra-aortic trunks successfully treated surgically with aorto-subclavian and aorto-innominate bypass. Two were performed via manubriotomy and a third case via standard median sternotomy because of concomitant coronary revascularisation. There was complete symptomatic relief on follow-up, and radiological imaging confirmed good flow in the grafts and post-stenotic arteries
Mortality, morbidity, and hospitalisations due to influenza lower respiratory tract infections, 2017: an analysis for the global burden of disease study 2017
Although the burden of influenza is often discussed in the context of historical pandemics and the threat of future pandemics, every year a substantial burden of lower respiratory tract infections (LRTIs) and other respiratory conditions (like chronic obstructive pulmonary disease) are attributable to seasonal influenza. The Global Burden of Disease Study (GBD) 2017 is a systematic scientific effort to quantify the health loss associated with a comprehensive set of diseases and disabilities. In this Article, we focus on LRTIs that can be attributed to influenza. Methods: We modelled the LRTI incidence, hospitalisations, and mortality attributable to influenza for every country and selected subnational locations by age and year from 1990 to 2017 as part of GBD 2017. We used a counterfactual approach that first estimated the LRTI incidence, hospitalisations, and mortality and then attributed a fraction of those outcomes to influenza. Findings: Influenza LRTI was responsible for an estimated 145 000 (95% uncertainty interval [UI] 99 000–200 000) deaths among all ages in 2017. The influenza LRTI mortality rate was highest among adults older than 70 years (16·4 deaths per 100 000 [95% UI 11·6–21·9]), and the highest rate among all ages was in eastern Europe (5·2 per 100 000 population [95% UI 3·5–7·2]). We estimated that influenza LRTIs accounted for 9 459 000 (95% UI 3 709 000–22 935 000) hospitalisations due to LRTIs and 81 536 000 hospital days (24 330 000–259 851 000). We estimated that 11·5% (95% UI 10·0–12·9) of LRTI episodes were attributable to influenza, corresponding to 54 481 000 (38 465 000–73 864 000) episodes and 8 172 000 severe episodes (5 000 000–13 296 000). Interpretation: This comprehensive assessment of the burden of influenza LRTIs shows the substantial annual effect of influenza on global health. Although preparedness planning will be important for potential pandemics, health loss due to seasonal influenza LRTIs should not be overlooked, and vaccine use should be considered. Efforts to improve influenza prevention measures are needed. Funding: Bill & Melinda Gates Foundation
Attitudes and practices of public health academics towards research funding from for-profit organizations: cross-sectional survey.
OBJECTIVES: The growing trend of for-profit organization (FPO)-funded university research is concerning because resultant potential conflicts of interest might lead to biases in methods, results, and interpretation. For public health academic programmes, receiving funds from FPOs whose products have negative health implications may be particularly problematic. METHODS: A cross-sectional survey assessed attitudes and practices of public health academics towards accepting funding from FPOs. The sampling frame included universities in five world regions offering a graduate degree in public health; 166 academics responded. Descriptive, bivariate, and logistic regression analyses were conducted. RESULTS: Over half of respondents were in favour of accepting funding from FPOs; attitudes differed by world region and gender but not by rank, contract status, % salary offset required, primary identity, or exposure to an ethics course. In the last 5Â years, almost 20% of respondents had received funding from a FPO. Sixty per cent of respondents agreed that there was potential for bias in seven aspects of the research process, when funds were from FPOs. CONCLUSIONS: Globally, public health academics should increase dialogue around the potential harms of research and practice funded by FPOs
A core outcome set for pre-eclampsia research:an international consensus development study
Objective: To develop a core outcome set for pre-eclampsia. Design: Consensus development study. Setting: International. Population: Two hundred and eight-one healthcare professionals, 41 researchers and 110 patients, representing 56 countries, participated. Methods: Modified Delphi method and Modified Nominal Group Technique. Results: A long-list of 116 potential core outcomes was developed by combining the outcomes reported in 79 pre-eclampsia trials with those derived from thematic analysis of 30 in-depth interviews of women with lived experience of pre-eclampsia. Forty-seven consensus outcomes were identified from the Delphi process following which 14 maternal and eight offspring core outcomes were agreed at the consensus development meeting. Maternal core outcomes: death, eclampsia, stroke, cortical blindness, retinal detachment, pulmonary oedema, acute kidney injury, liver haematoma or rupture, abruption, postpartum haemorrhage, raised liver enzymes, low platelets, admission to intensive care required, and intubation and ventilation. Offspring core outcomes: stillbirth, gestational age at delivery, birthweight, small-for-gestational-age, neonatal mortality, seizures, admission to neonatal unit required and respiratory support. Conclusions: The core outcome set for pre-eclampsia should underpin future randomised trials and systematic reviews. Such implementation should ensure that future research holds the necessary reach and relevance to inform clinical practice, enhance women's care and improve the outcomes of pregnant women and their babies. Tweetable abstract: 281 healthcare professionals, 41 researchers and 110 women have developed #preeclampsia core outcomes @HOPEoutcomes @jamesmnduffy. [Correction added on 29 June 2020, after first online publication: the order has been corrected.].</p
Campylobacter Infection as a Trigger for Guillain-Barré Syndrome in Egypt
BACKGROUND: Most studies of Campylobacter infection triggering Guillain-Barré Syndrome (GBS) are conducted in western nations were Campylobacter infection and immunity is relatively rare. In this study, we explored Campylobacter infections, Campylobacter serotypes, autoantibodies to gangliosides, and GBS in Egypt, a country where Campylobacter exposure is common. METHODS: GBS cases (n = 133) were compared to age- and hospital-matched patient controls (n = 374). A nerve conduction study was performed on cases and a clinical history, serum sample, and stool specimen obtained for all subjects. RESULTS: Most (63.3%) cases were demyelinating type; median age four years. Cases were more likely than controls to have diarrhea (29.5% vs. 22.5%, Adjusted Odds Ratio (ORa) = 1.69, P = 0.03), to have higher geometric mean IgM anti-Campylobacter antibody titers (8.18 vs. 7.25 P<0.001), and to produce antiganglioside antibodies (e.g., anti-Gd1a, 35.3 vs. 11.5, ORa = 4.39, P<0.0001). Of 26 Penner:Lior Campylobacter serotypes isolated, only one (41:27, C. jejuni, P = 0.02) was associated with GBS. CONCLUSIONS: Unlike results from western nations, data suggested that GBS cases were primarily in the young and cases and many controls had a history of infection to a variety of Campylobacter serotypes. Still, the higher rates of diarrhea and greater antibody production against Campylobacter and gangliosides in GBS patients were consistent with findings from western countries
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