16 research outputs found
The Online Shopping Acceptance Model
E-commerce in general, and online shopping in particular, are becoming popular ways of utilizing the Internet throughout the world. Social media is also becoming a widespread tool, not only for interaction with others but also for marketing. Despite this trend, there is a dearth of knowledge about the acceptance of online shopping and the use of social media in developing countries such as Saudi Arabia. Technology adoption levels in Saudi Arabia are growing rapidly but have yet to reach their full potential. One of the leading theories explaining online shopping behaviour – the online shopping acceptance model (OSAM) – has not been employed in previous studies of social media use or in developing countries such as Saudi Arabia to understand online shopping. To address this research problem, the researcher implemented a study using a positivist approach. Quantitative data was gathered using an online survey. This survey was conducted with Saudi residents who engage with online shopping. A data set of 423 completed survey responses is used in this thesis for statistical analysis. The data was collected using a random sample and was collected from January to September 2015. The structural equation modelling tested the hypothesised relationships between the constructs as postulated in the model. Nineteen of the hypothesised links were supported and ten were rejected. Eventually, the model that has statistical and explanatory power was confirmed. The findings indicate a positive relationship between online shopping intention and other factors of online shopping acceptance in Saudi Arabia. A positive relationship is also seen between online shopping orientation and online shopping experience. The case examines the relationship between online shopping orientation and online shopping motivation. The same applies for the relationship between online shopping and social media through the mediation of online shopping intention. This research contributes to understanding the role of social media in OSAM in Saudi Arabia as a developing country, as OSAM incorporates social media as a new factor that influences acceptance aside from what is traditionally stipulated. A second contribution is the finding that shopping orientation is the most important construct affecting online shopping intention in Saudi Arabia
Study of the properties of thermoset materials derived from epoxidized soybean oil and protein fillers
[EN] Novel bio-based thermoset formulations were prepared by using epoxidized soybean oil (ESBO), nadic methyl anhydride as a hardener and with different types of proteins as fillers. In the first part of the study, the effect of the protein-type (wheat gluten, soy protein, casein and ovalbumin) on cured ESBO materials was investigated. Thermal and mechanical properties were characterized by flexural tests, Shore D hardness, Charpy impact tests, Vicat softening temperature and heat deflection temperature. In addition, a study of the morphology of fractured surfaces by scanning electron microscopy was carried out. In general, the addition of protein-based fillers improved the mechanical and thermal properties. It was found that the highest increase of thermal and mechanical properties was achieved by ovalbumin. In the second part of the work, the effect of the total amount of ovalbumin filler was studied. Bio-based thermoset materials from ESBO and 15 wt %
ovalbumin improved flexural modulus more than 150 % when compared to the unfilled material. Similar evolution was observed for other mechanical properties. Moreover, the brittleness of this composition was the minimum from the studied systems. A direct relationship between energy absorption capacity and morphologies of the failure surface was evidenced by SEM.This work is a part of the project IPT-310000-2010-037,"ECOTEXCOMP: Research and development of textile structures useful as reinforcement of composite materials with marked ecological character" funded by the "Ministerio de Ciencia e Innovacion", with an aid of 189540.20 euros, within the "Plan Nacional de Investigacion Cientifica, Desarrollo e Innovacion Tecnologica 2008-2011" and funded by the European Union through FEDER funds, Technology Fund 2007-2013, "Operational Programme on R+D+I for and on behalf of the companies". Also, Generalitat Valenciana ACOMP/2012/087 is acknowledged for financial support.Fombuena Borrás, V.; Sánchez Nacher, L.; Samper Madrigal, MD.; Juárez Varón, D.; Balart Gimeno, RA. (2013). Study of the properties of thermoset materials derived from epoxidized soybean oil and protein fillers. Journal of the American Oil Chemists' Society. 90(3):449-457. https://doi.org/10.1007/s11746-012-2171-2S449457903Alonso MV, Oliet M, Garcia J, Rodriguez F, Echeverria J (2006) Gelation and isoconversional kinetic analysis of lignin-phenol-formaldehyde resol resins cure. Chem Eng J 122:159–166Altuna FI, Esposito LH, Ruseckaite RA, Stefani PM (2011) Thermal and mechanical properties of anhydride-cured epoxy resins with different contents of bio-based epoxidized soybean oil. J Appl Polym Sci 120:789–798Boquillon N, Fringant C (2000) Polymer networks derived from curing of epoxidised linseed oil: influence of different catalysts and anhydride hardeners. 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Assessment of occupational noise‐related hearing impairment among dental health personnel
Experimental and theoretical studies of (E)-N′-1-(4-propylbenzylidene)nicotinohydrazide as corrosion inhibitor of mild steel in 1 M HCl
β-Lactamase Production in Key Gram-Negative Pathogen Isolates from the Arabian Peninsula
Infections due to Gram-negative bacilli (GNB) are a leading cause of morbidity and mortality worldwide. The extent of antibiotic resistance in GNB in countries of the Gulf Cooperation Council (GCC), namely, Saudi Arabia, United Arab Emirates, Kuwait, Qatar, Oman, and Bahrain, has not been previously reviewed. These countries share a high prevalence of extended-spectrum-β-lactamase (ESBL)- and carbapenemase-producing GNB, most of which are associated with nosocomial infections. Well-known and widespread β-lactamases genes (such as those for CTX-M-15, OXA-48, and NDM-1) have found their way into isolates from the GCCstates. However, less common and unique enzymes have also been identified. These include PER-7, GES-11, and PME-1. Several potential risk factors unique to the GCC states may have contributed to the emergence and spread of β-lactamases, including the unnecessary use of antibiotics and the large population of migrant workers, particularly from the Indian subcontinent. It is clear that active surveillance of antimicrobial resistance in the GCC states is urgently needed to address regional interventions that can contain the antimicrobial resistance issue