The Mediation Effect of Trusting Beliefs on the Relationship Between Expectation-Confirmation and Satisfaction with the Usage of Online Product Recommendation

Online Product Recommendations (OPRs) are increasingly available to onlinecustomers as a value-added self-service in evaluating and choosing a product.Research has highlighted several advantages that customers can gain from usingOPRs. However, the realization of these advantages depends on whether and towhat extent customers embrace and fully utilise them. The relatively low OPR USAgerate indicates that customers have not yet developed trust in OPRs’ performance.Past studies also have established that satisfaction is a valid measure of systemperformance and a consistent significant determinant of users’ continuous systemusage. Therefore, this study aimed to examine the mediation effect of trustingbeliefs on the relationship between expectation-confirmation and satisfaction. Theproposed research model is tested using data collected via an online survey from626 existing users of OPRs. The empirical results revealed that social-psychologicalbeliefs (perceived confirmation and trust) are significant contributors to customersatisfaction with OPRs. Additionally, trusting beliefs partially mediate the impactof perceived confirmation on customer satisfaction. Moreover, this study validatesthe extensions of the interpersonal trust construct to trust in OPRs and examinesthe nomological validity of trust in terms of competence, benevolence, andintegrity. The findings provide a number of theoretical and practical implications.&nbsp

Chemical Speciation and Potential Mobility of Heavy Metals in the Soil of Former Tin Mining Catchment

This study describes the chemical speciation of Pb, Zn, Cu, Cr, As, and Sn in soil of former tin mining catchment. Total five sites were selected for sampling and subsequent subsamples were collected from each site in order to create a composite sample for analysis. Samples were analysed by the sequential extraction procedure using optical emission spectrometry (ICP OES). Small amounts of Cu, Cr, and As retrieved from the exchangeable phase, the ready available for biogeochemical cycles in the ecosystem. Low quantities of Cu and As could be taken up by plants in these kind of acidic soils. Zn not detected in the bioavailable forms while Pb is only present in negligible amounts in very few samples. The absence of mobile forms of Pb eliminates the toxic risk both in the trophic chain and its migration downwards the soil profile. The results also indicate that most of the metals have high abundance in residual fraction indicating lithogenic origin and low bioavailability of the metals in the studied soil. The average potential mobility for the metals giving the following order: Sn > Cu > Zn > Pb > Cr > As

Calli Essential Oils Synergize with Lawsone against Multidrug Resistant Pathogens.

The fast development of multi-drug resistant (MDR) organisms increasingly threatens global health and well-being. Plant natural products have been known for centuries as alternative medicines that can possess pharmacological characteristics, including antimicrobial activities. The antimicrobial activities of essential oil (Calli oil) extracted from the Calligonum comosum plant by hydro-steam distillation was tested either alone or when combined with lawsone, a henna plant naphthoquinone, against MDR microbes. Lawsone showed significant antimicrobial activities against MDR pathogens in the range of 200-300 µg/mL. Furthermore, Calli oil showed significant antimicrobial activities against MDR bacteria in the range of 180-200 µg/mL, Candida at 220-240 µg/mL and spore-forming Rhizopus fungus at 250 µg/mL. Calli oil's inhibition effect on Rhizopus, the major cause of the lethal infection mucormycosis, stands for 72 h, followed by an extended irreversible white sporulation effect. The combination of Calli oil with lawsone enhanced the antimicrobial activities of each individual alone by at least three-fold, while incorporation of both natural products in a liposome reduced their toxicity by four- to eight-fold, while maintaining the augmented efficacy of the combination treatment. We map the antimicrobial activity of Calli oil to its major component, a benzaldehyde derivative. The findings from this study demonstrate that formulations containing essential oils have the potential in the future to overcome antimicrobial resistance

Noise Effects on a Proposed Algorithm for Signal Reconstruction and Bandwidth Optimization

The development of wireless technology in recent years has increased the demand for channel resources within a limited spectrum. The system\u27s performance can be improved through bandwidth optimization, as the spectrum is a scarce resource. To reconstruct the signal, given incomplete knowledge about the original signal, signal reconstruction algorithms are needed. In this paper, we propose a new scheme for reducing the effect of adding additive white Gaussian noise (AWGN) using a noise reject filter (NRF) on a previously discussed algorithm for baseband signal transmission and reconstruction that can reconstruct most of the signal’s energy without any need to send most of the signal’s concentrated power like the conventional methods, thus achieving bandwidth optimization. The proposed scheme for noise reduction was tested for a pulse signal and stream of pulses with different rates (2, 4, 6, and 8 Mbps) and showed good reconstruction performance in terms of the normalized mean squared error (NMSE) and achieved an average enhancement of around 48%. The proposed schemes for signal reconstruction and noise reduction can be applied to different applications, such as ultra-wideband (UWB) communications, radio frequency identification (RFID) systems, mobile communication networks, and radar systems

C–O isotope geochemistry of the Florida phosphate of Four Corners and Hardee County mines, USA: Implication for genesis and diagenesis

© 2017 Elsevier B.V. The study area located in Florida, USA and emphasized on low-grade phosphorites in Hardee County (HC) and Four Corners (FC) mining areas. The main purpose of this study is to apply a standard geochemical technique to understand the diagenetic history and paleo-environmental aspects of phosphates within one of the major phosphate deposits in the USA. The effect of diagenesis on the phosphate minerals was studied by isotope analysis of the phosphate bone fragments and phosphatized mudclasts and rods. The environmental conditions that prevailed during the life of organisms were assessed by isotope analysis of the shark teeth. In this paper, variation in stable isotope (δ18O and δ13C) signatures of structural carbonate in rocks and shark teeth were studied in Florida phosphate. The studied samples show negative values for both δ13C and δ18O isotopes of structural carbonate. The light mudclast samples shows higher oxygen ratios (− 1.6) than the dark mudclasts (− 2.3) in Hardee County, whereas those values were lower, − 2.3 and − 3, respectively, in Four Corners samples. The shark teeth found in the deposits show narrow variations in values of δ13C (− 3.4 to − 4.9%o) and δ18O (− 1.4 to 2.1%o) isotope. The bone fragments in the deposits are more similar to the light mudclasts regarding the isotope ratios and carbonate content. The alteration is evident in the Florida phosphorites where δ18O values of bulk teeth are higher than those of bones and mudclast. This alteration could be because of increasing crystallinity and decreasing carbonate content with increasing depth of burial

Ultrastructure of antennal sensillae of the samsum ant, Pachycondyla sennaarensis (Hymenoptera: Formicidae)

Black ant (Samsum), Pachycodyla sennarrensis, stings and injects venom and inflicts allergy (a rare clinical problem) due to its local and systemic reaction, which is considered as a health hazard amongst Saudi society. Thus, black ant is a source of serious concern for the government and experts as well.  Ultramorphological variations, distribution, differential sensillae counts (DSC) and total sensillae counts (TSC), were identified and estimated as a complementary part of the peripheral nervous system on the antennae of worker samsum ant, P. sennarrensis in order to understand its behavioral ecology. Based on scanning electron micrographs, four types of sensillae constituted with three trichoid types, which is an abundant form with a high distribution density at the apex, but a low density at subsequent proximal flagellomere of the antenna and a placoid type of sensillae (a rare form mostly found in the middle of the flagellum, that is, on the 4th, 5th and 6th flagellomere) were categorised. It is documented that nonporous trichoid type of sensillae are mechanoreceptors and thermoreceptors, whereas, the placoid types are olfactory receptors. Present findings in an indigenous species in Saudi Arabia may help in understanding the ecological behaviour of the ant, which subsequently may form the basis in producing its effective control measure in future.Key words: Samsum ants, Pachycondyla sennarrensis, ultrastructure, antenna, sensillae

Perspectives for a mixed two-qubit system with binomial quantum states

The problem of the relationship between entanglement and two-qubit systems in which it is embedded is central to the quantum information theory. This paper suggests that the concurrence hierarchy as an entanglement measure provides an alternative view of how to think about this problem. We consider mixed states of two qubits and obtain an exact solution of the time-dependent master equation that describes the evolution of two two-level qubits (or atoms) within a perfect cavity for the case of multiphoton transition. We consider the situation for which the field may start from a binomial state. Employing this solution, the significant features of the entanglement when a second qubit is weakly coupled to the field and becomes entangled with the first qubit, is investigated. We also describe the response of the atomic system as it varies between the Rabi oscillations and the collapse-revival mode and investigate the atomic inversion and the Q-function. We identify and numerically demonstrate the region of parameters where significantly large entanglement can be obtained. Most interestingly, it is shown that features of the entanglement is influenced significantly when the multi-photon process is involved. Finally, we obtain illustrative examples of some novel aspects of this system and show how the off-resonant case can sensitize entanglement to the role of initial state setting.Comment: 18 pages, 9 figure

Selective harmonic elimination in awide modulation range using modified Newton-raphson and pattern generation methods for a multilevel inverter

Considering the aim of having low switching losses, especially in medium-voltage and high-power converters, the pre-programmed pulse width modulation technique is very useful because the generated harmonic content can be known in advance and optimized. Among the different low switching frequency techniques, the Selective Harmonics Elimination (SHE) modulation method is most suitable because of its direct control over the harmonic spectrum. This paper proposes a method for obtaining multiple solutions for selectively eliminating specific harmonics in a wide range of modulation indices by using modified Newton-Raphson (NR) and pattern generation techniques. The different pattern generation and synthesis approach provide more degrees of freedom and a way to operate the converter in a wide range of modulation. The modified Newton-Raphson technique is not complex and ensures fast convergence on a solution. Moreover, multiple solutions are obtained by keeping a very small increase in the modulation index. In the previous methods, solutions were not obtainable at all modulation indices. In this paper, only exact solutions to the low-order harmonics elimination for Cascaded H-bridge inverter are reported for all modulation indices. Analytical and simulation results prove the robustness and correctness of the technique proposed in this paper. 2018 by the authors.Acknowledgments: This (publication, report, etc.) was made possible by NPRP grant # [X-033-2-007] from the Qatar National Research Fund (a member of Qatar Foundation).Scopu

Unusual rainfall shift during monsoon period of 2010 in Pakistan: Flash flooding in Northern Pakistan and riverine flooding in Southern Pakistan

Floods due to “blocking event” in the jet stream during 2010 caused intense rainfall and flash floods in northern Pakistan which resulted to riverine flooding in southern Pakistan. In the beginning of July 2010, changes in summer monsoon rainfall patterns caused the most severe flooding in Pakistan history. Process control charts suggest that monsoon pattern was not normal which made one-fifth of the country to be inundated. In this study, our main concern was to check the upward shifts (floods) in the rainfall pattern of all provinces of Pakistan. Results indicate that there was significant and sudden shift in the rainfall pattern of monsoon in 2010 which might be due to prolong “blocking event” in the jet stream. In late July, rainwater from the highlands entered major rivers which affected nearby areas of the Indus River. More than 250 mm of rain fell over a 36-h period in late July. Abeyant policies by the Pakistan Irrigation Department (PID) caused destruction in Jacobabad which was not a normal Indus waterway. The first week of August marked the worst week of extreme flooding in southern Pakistan. Flood simulation overylay technique showed the affected areas of the country in comparison with normal waterways by using vector and raster data images.Key words: Indus River, monsoon, flooding in 2010, rainfall pattern, Climate Change, Floods