Exploring the effects of consumers’ trust : a predictive model for satisfying buyers’ expectations based on sellers’ behaviour in the marketplace

In recent years, Consumer-to-Consumer (C2C) marketplaces have become very popular among Internet users. However, compared to traditional Business-to-Consumer (B2C) stores, most modern C2C marketplaces are reported to be associated with stronger negative sentiments among consumers. These negative sentiments arise from the inability of sellers to meet certain buyers’ expectations and are linked to the low trust relationship among sellers and buyers in C2C marketplaces. The growth of these negative emotions might jeopardize buyers’ decisions to opt for C2C marketplaces in their future purchase intentions. In the present study, we extend the definition of trust as an emotion to cover the digital world and demonstrate the trust model currently used by most online stores. Based on the buyer’s behaviour in the C2C marketplace, we propose a conceptual framework to predict trust between the buyer and the seller. Given that C2C marketplaces are rich sources of data for trust mining and sentiment analysis, we perform text mining on Airbnb to predict the trust level in host descriptions of offered facilities. The data are acquired from the US city of Ashville, Alabama, and Manchester in the UK. The results of the analysis demonstrate that guest negative feedback in reviews are high when the description of the host’s property has the emotion of joy only. By contrast, guest negative sentiments in reviews are at a minimum when the host’s sentiment has mixed emotions (e.g., joy and fear)

Customer Awareness and Satisfaction of Islamic Retail Products in Kuwait

The market for Islamic banking has grown rapidly over the past few years, and this high growth is expected to continue for the near future in Kuwait Banking Industry. At the same time the competition market is being reshaped, with more Islamic financial services institutions than before entering the market. Within this competitive environment customers have been identified as the most important foundational pillar for business sustainability.  Using a questionnaire distributed to 150 Kuwaiti client deals with Islamic banks, the study aimed to examine the factors affecting Kuwaiti customers in the choice of the Islamic Bank, which they deal with, and to study the level of awareness customers have on the Islamic principles that stand behind each retail service provided by the Kuwaiti Islamic Banks. The study also examined the level of satisfaction of services provided by these banks. The study found the twenty three factors investigated by the study were very important in choosing Islamic banks in Kuwait. One Islamic factor only (Bank reputation in regards of abidance with Sharia principles) was one of the first five factors but it took last place. This mean that Kuwaiti customers seek more than abidance by sharia low, they want the same things customers of traditional banks requests from their bank. Kuwaiti customers are aware of Tawaroq and Islamic credit cards, but they aren’t fully aware of Mudarabah, Murabaha, Musharaka and Ijara. The study also found that in spite of a relatively high degree of satisfaction by Kuwaiti customers in general, they are still not fully satisfied with some areas related to Kuwaiti Islamic banks including adherence to Shariah principles. Keywords: Satisfaction, Customer Awareness, Islamic Banks, Islamic Shariah, Mudarabah, Murabaha, Musharaka and Ijara

Some Immunologic Evaluations of Toxoplasmosis in Iraqi Aborted Females

Forty-eight aborted women (Iraqi Arab Muslims) at the first trimester with a serological evidence of toxoplasmosis were investigated. Two age- and ethnic-matched control groups were included: 40 aborted women due to accidental events (Control I), and 40 unmarried (virgin) women (Control II). The subjects were evaluated for the following parameters: HLA-class I antigens (A, B and Cw), blood groups, total and differential counts of leukocytes, lymphocyte subpopulations (CD3+, CD4+ and CD20+ cells), phagocytosis of heat-killed yeast (phagocytic index and NBT index), and total serum levels of immunoglobulins (IgA, IgG and IgM) and complement components (C3 and C4). The HLA-A2 and -Cw8 antigens were significantly increased in the patients, while A3 antigen was significantly decreased. Blood group phenotypes in patients and controls also showed significant variations. The total and differential counts of leukocytes showed no significant differences between patients and controls, with the exception of lymphocytes, which showed a significant decreased count in the patients compared to control II. However, the lymphocyte subpopulations showed a significant increased percentage in patients. The phagocytic index was approximated in patients and controls, while NBT index was significantly decreased. Total serum level of IgG was significantly increased in the patients, while IgA, IgM, C3 and C4 levels did not maintain such variation

Isolation and characterization of native Bacillus thuringiensis strains from Saudi Arabia with enhanced larvicidal toxicity against the mosquito vector Anopheles gambiae (s.l.).

BACKGROUND: Worldwide, mosquito vectors are transmitting several etiological agents of important human diseases, including malaria, causing millions of deaths every year. In Saudi Arabia, as elsewhere, vector-control is based mostly on chemical insecticides which may be toxic and cause environmental deprivation. Here, to support the development of bio-pesticide alternatives, a study was conducted to identify native Bacillus thuringiensis (Bt) isolates with improved toxicity against the malaria vector, Anopheles gambiae (s.l.). METHODS: Sixty-eight Bt isolates were obtained from 300 soil and other samples collected from 16 sites across Saudi Arabia. Bt identification was based on morphological characteristics of colonies, shape of parasporal crystals and biochemical profiles. After characterization of their mosquitocidal activity, larvicidal strains were described through 16S ribosomal DNA gene sequencing, cry, cyt and chi genes PCR-amplification profiles, and SDS-PAGE protein analyses. RESULTS: Spherical Bt crystals were predominant amongst the 68 isolates (34%), while irregular, bi-pyramidal and spore-attached crystals were found in 32, 13 and 21% of strains, respectively. LC50 and LC90 bioassays showed that 23/68 isolates were larvicidal, with distinct biochemical activity profiles compared to non-larvicidal Bt strains. Eight larvicidal strains showed larvicidal activity up to 3.4-fold higher (LC50 range: 3.90-7.40 μg/ml) than the reference Bti-H14 strain (LC50 = 13.33 μg/ml). Of these, 6 strains had cry and cyt gene profiles similar to Bti-H14 (cry4Aa, cry4Ba, cry10, cry11, cyt1Aa, cyt1Ab, cyt2Aa). The seventh strain (Bt63) displaying the highest larvicidal activity (LC50 = 3.90 μg/ml) missed the cry4Aa and cyt1Ab genes and had SDS-PAGE protein profiles and spore/crystal sizes distinct from Bti-H14. The eight strain (Bt55) with LC50 of 4.11μg/ml had cry and cyt gene profiles similar to Bti-H14 but gave a chi gene PCR product size of 2027bp. No strains harbouring cry2, cry17 + 27, cry24 + 40, cry25, cry29, cry30, or cyt2Ba were detected. CONCLUSION: This study represents the first report of several Saudi indigenous Bt strains with significantly higher larvicidal efficacy against An. gambiae than the reference Bti-H14 strain. The very high toxicity of the Bt63 strain, combined with distinct cry and cyt genes and SDS-PAGE-protein profiles makes it a promising candidate for future applications in mosquito bio-control

Prevalence and Determinants of Metabolic Syndrome in Qatar: Results from a National Health Survey

OBJECTIVES: To determine optimum measurements for abdominal obesity and to assess the prevalence and determinants of metabolic syndrome in Qatar. DESIGN: National health survey. SETTING: Qatar National STEPwise Survey conducted by the Supreme Council of Health during 2012. PARTICIPANTS: 2496 Qatari citizens aged 18-64 representative of the general population. PRIMARY AND SECONDARY OUTCOME MEASURES: Measure of obesity (body mass index, waist circumference or waist-to-height ratio) that best identified the presence of at least 2 other factors of metabolic syndrome; cut-off values of waist circumference; frequency of metabolic syndrome. RESULTS: Waist circumference ≥102 for men and ≥94 cm for women was the best predictor of the presence of other determinants of metabolic syndrome (raised blood pressure, fasting blood glucose, triglycerides and reduced high-density lipoprotein cholesterol). Using these values, we identified 28% of Qataris with metabolic syndrome, which is considerably lower than the estimate of 37% calculated using the International Diabetes Federation (IDF) criteria. Restricting the analysis to participants without known elevated blood pressure, elevated blood sugar or diabetes 16.5% would be classified as having metabolic syndrome. In a multivariable logistic regression analysis, the prevalence of metabolic syndrome increased steadily with age (OR=3.40 (95% CI 2.02 to 5.74), OR=5.66 (3.65 to 8.78), OR=10.2 (5.98 to 17.6) and OR=18.2 (7.01 to 47.5) for those in the age group \u2730-39\u27, \u2740-49\u27, \u2750-59\u27, \u2760-64\u27 vs \u2718-29\u27; p CONCLUSIONS: Waist circumference was the best measure of obesity to combine with other variables to construct a country-specific definition of metabolic syndrome in Qatar. Approximately 28% of adult Qatari citizens satisfy the criteria for metabolic syndrome, which increased significantly with age. Education and physical activity were inversely associated with this syndrome

Association between the inflammatory potential of diet and stress among female college students

A pro-inflammatory diet may have an adverse influence on stress and inflammatory biomarker levels among college students. The dietary inflammatory index (DII®) is a tool used to assess the inflammatory potential of a diet. However, evidence for the association between DII and stress is limited. We examined the association between energy-adjusted DII (E-DIITM), high sensitivity-C-reactive protein [hs-CRP], and stress among female college students. This cross-sectional study included 401 randomly selected female students, aged 19-35 years. Data collection included blood, anthropometric measurements, a healthy-history questionnaire, the perceived stress scale (PSS-10), the Saudi food frequency questionnaire (FFQ), and E-DII. Multiple linear regression analyses were used to examine the association between FFQ-derived E-DII score, hs-CRP, and PSS. A higher E-DII score per 1SD (1.8) was associated with a 2.4-times higher PSS score (95% CI: 1.8, 3.1). Higher hs-CRP per 1SD (3.3 mg/L) was associated with a 0.9 (95% CI: 0.7-1.1) times higher PSS score, independent of lifestyle and dietary factors. Our findings indicate that pro-inflammatory diets were highly prevalent among Saudi college students and were associated with higher stress levels. Consideration of the role of stress and focusing on anti-inflammatory foods may be key for healthier dietary habits

Study of orifice design on oleo-pneumatic shock absorber

Aircraft oil-strut shock absorbers rely on orifice designs to control fluid flow and optimize damping performance. However, the complex nature of cavitating flows poses significant challenges in predicting the influence of orifice geometry on energy dissipation and system reliability. This study presents a comprehensive computational fluid dynamics (CFD) analysis of the effects of circular, rectangular, semicircular, and cutback orifice profiles on the internal flow characteristics and damping behavior of oleo-pneumatic shock absorbers. High-fidelity simulations reveal that the rectangular orifice generates higher damping pressures and velocity magnitude than those generated by others designs, while the semicircular shape reduces cavitation inception and exhibits a more gradual pressure recovery. Furthermore, the study highlights the importance of considering both geometric and thermodynamic factors in the design and analysis of cavitating flow systems, as liquid properties and vapor pressure significantly impact bubble growth and collapse behavior. Increasing the orifice length had a negligible impact on damping but moderately raised orifice velocities. This research provides valuable insights for optimizing shock absorber performance across a range of operating conditions, ultimately enhancing vehicle safety and passenger comfort.This research was funded by Innovate UK grant number 10002411, under the ATI/IUK Project: LANDOne, with Airbus UK as Industrial Lead

Unsteady multiphase simulation of oleo-pneumatic shock absorber flow

The internal flow in oleo-pneumatic shock absorbers is a complex multiphysics problem combining the interaction between highly unsteady turbulent flow and multiphase mixing, among other effects. The aim is to present a validated simulation methodology that facilitates shock absorber performance prediction by capturing the dominant internal flow physics. This is achieved by simulating a drop test of approximately 1 tonne with an initial contact vertical speed of 2.7 m/s, corresponding to a light jet. The flow field solver is ANSYS Fluent, using an unsteady two-dimensional axisymmetric multiphase setup with a time-varying inlet velocity boundary condition corresponding to the stroke rate of the shock absorber piston. The stroke rate is calculated using a two-equation dynamic system model of the shock absorber under the applied loading. The simulation is validated against experimental measurements of the total force on the shock absorber during the stroke, in addition to standard physical checks. The flow field analysis focuses on multiphase mixing and its influence on the turbulent free shear layer and recirculating flow. A mixing index approach is suggested to facilitate systematically quantifying the mixing process and identifying the distinct stages of the interaction. It is found that gas–oil interaction has a significant impact on the flow development in the shock absorber’s upper chamber, where strong mixing leads to a periodic stream of small gas bubbles being fed into the jet’s shear layer from larger bubbles in recirculation zones, most notably in the corner between the orifice plate and outer shock absorber wall.This research was funded by Innovate UK grant number 10002411, under the ATI/IUK Project: LANDOne, with Airbus UK as Industrial Lead

Numerical investigation of orifice nearfield flow development in oleo-pneumatic shock absorbers

The flow field development through a simplified shock absorber orifice geometry is investigated using a single phase Large Eddy Simulation. Hydraulic oil is used as the working fluid with a constant inlet velocity and an open top boundary to allow the study to focus on the free shear layer and the flow development in the vicinity of the main orifice. The flow field is validated using standard mixing layer dynamics. The impact of the orifice shape is discussed with regards to the initial free shear layer growth, boundary layer development and the potential appearance of cavitation bubbles. Observations are made regarding the presence of flow field disturbances upstream of and through the orifice, thereby, leading to a notable turbulence intensity level in those regions.Innovate UK: 263261 and Airbus U