A Study of Antecedents of Sense of Presence in Virtual World: Virtual Presence vs. Social Presence

Virtual World as an electronic artificial environment, enables users to have an identity while interacting with others is one of the new instances of Computer-Mediated Communications environment. Our study aims to elaborate the two types of presence in virtual world and their effects on users’ satisfaction and loyalty in second life. In addition we try to elaborate the factors that affect virtual and social presence. We used survey in order to collect data from a student sample frame. Our samples are students who at least have three weeks experience with second life in order to measure our model. Results of the research suggested that cognitive absorption positively influence virtual presence and sense of belonging positively influence social presence. In addition our results suggested that sense of presence in virtual world increase satisfaction and loyalty among virtual world users

A Study of the Effect of Privacy Assurance Mechanisms on Self-disclosure in Social Networking Sites from the View of Protection Motivation Theory

Because of the predominant and rampant of social networking sites (SNSs), users’ information privacy issue becomes an important challenge not only for SNS users but also for the SNS service providers and governing organizations. This study’s objectives are: (1) to study how assurance mechanisms affect SNS users’ self-disclosure intention by applying protection motivation theory (PMT), and (2) to empirically test the perceived privacy concern as part of the PMT in order to predict self-disclosure on SNS. There are a number of expected contributions for this study. First, this study applies PMT in order to understand how assurance mechanisms applied by SNSs affect users to disclose their personal information. Second, we introduce the customizing privacy as an assurance mechanism which has not been studied in previous literature. Finally, we consider fear component of PMT which has not been studied by previous researchers who applied PMT in this context

Genotype and phenotype of COVID-19: Their roles in pathogenesis

COVID-19 is a novel coronavirus with an outbreak of unusual viral pneumonia in Wuhan, China, and then pandemic. Based on its phylogenetic relationships and genomic structures the COVID-19 belongs to genera Betacoronavirus. Human Betacoronaviruses (SARS-CoV-2, SARS-CoV, and MERS-CoV) have many similarities, but also have differences in their genomic and phenotypic structure that can influence their pathogenesis. COVID-19 is containing single-stranded (positive-sense) RNA associated with a nucleoprotein within a capsid comprised of matrix protein. A typical CoV contains at least six ORFs in its genome. All the structural and accessory proteins are translated from the sgRNAs of CoVs. Four main structural proteins are encoded by ORFs 10, 11 on the one-third of the genome near the 3′-terminus. The genetic and phenotypic structure of COVID-19 in pathogenesis is important. This article highlights the most important of these features compared to other Betacoronaviruses. keywords: COVID-19, Genotype, Pathogenesis, Phenotyp

Apple and quince peroxidase activity in response to essential oils application

Enzymatic browning arises by peroxidase in fruits. However, essential oils are recognized as natural antioxidant agents. So in this study, the effect of thyme, coriander and rosemary essential oils were evaluated on the reduction of peroxidase activity in apples (Malus domestica Mill. cv Golden delicious), (M. domestica Mill. cv Red delicious) and quince (Cydonia oblonga Mill. cv. Esfahan). In this study, 50, 75, 100 or 200 μl/100 ml concentrations of pure essential oil were applied in vivo and in vitro. The results revealed the control samples of golden delicious, red delicious and quince had 185, 142.5 and 300 (units/min/g) peroxidase activity, respectively. In vitro 75 μl/100 ml of thyme and in vivo 50 μl/100 ml of thyme and 200 μl/100 ml of rosemary essential oils exerted the highest antioxidant ability (reductions in peroxidase activity by 92%) in the golden delicious. In vitro experiments were focused on the coriander essential oil treatments offering potential antioxidant benefits in the red delicious. Peroxidase activity was affected by in vivo 50 μl/100 ml concentrations of pure rosemary essential oil (reductions in peroxidase activity by 90%) when the enzyme was obtained from quince.Key words: Peroxidase, essential oil, antioxidant, apple, quince

High-tech biomedical research: lessons from Iran's experience

Iran has recently made a significant progress in the field of biomedical science and launched an appreciable number of new high-tech biomedical research projects. Review of Iran's experience in advancing its biomedical research and the pitfalls the country encountered during the years of its progress could be of interest to other countries with similar technological conditions. As needs assessment and human resources have pivotal roles in any research infrastructure, here, we have delineated these factors and explored ways by which optimum advantage could be gained from them

A Study of the Effect of Privacy Assurance Mechanisms on Self-disclosure in Social Networking Sites from the View of Protection Motivation Theory

Along with recent advancement of web technologies, social networking sites (SNSs) affect people’s life styles by enabling them to perform different activities which are not easy to do before. Predominant uses of SNSs allow users to quickly access and easily share personal information. In turn, users’ information privacy issues become important challenge. Drawing upon Protection Motivation Theory, this research investigates the effect of privacy assurance mechanisms (i.e., privacy assurance statements and privacy customization) on privacy concern and disclosure behavior. The results show that privacy assurance statements significantly influence SNS users’ privacy concern by affecting users’ assessment of threat susceptibility and effectiveness of assurance mechanisms; privacy customization features significantly influence users’ self-efficacy and perceived effectiveness of assurance mechanisms; SNS users’ privacy concern results form a risk calculus process in which users assess the threat and available coping mechanisms; and the effect of privacy concern on self-disclosure mediates by users’ protection motivation

Continued Usage and Location Disclosure of Location-Based Applications: A Necessity for Location Intelligence

Location-based applications (LBA) have been widely accepted and used for different purposes ranging from navigation to dating or gaming. Most LBAs ask users to provide access to location data for more efficient and personalized location-based services. Location intelligence as an emerging area of business intelligence relies heavily on disclosing location information by users. This research builds a continuance usage and location disclosure model from the expectation-confirmation perspective. The effect of benefit expectations on usefulness and satisfaction is hypothesized. In addition, the positive effect of usefulness on satisfaction and continuance intention is postulated. After collecting survey data from main LBA users, the results of the analysis support the proposed model. Findings contribute to the current literature in business intelligence by focusing on location disclosure behavior in the context of LBAs and the necessity of this type of information for location intelligence

Antecedents of Online Customers Reviews’ Helpfulness: A Support Vector Machine Approach

Online customer reviews (OCRs) have become an important part of online customers’ decision making and People use online reviews to make decision to buy or not to buy products and services. This study aims to answer two research questions: (1) what are the antecedents of helpfulness of online reviews based on their contents? (2) How do content-based cues on OCRs influence their helpfulness? We posit a research model to study the effect of peripheral and central cues in OCRs on online review helpfulness. Online review web pages will be collected from Amazon website using a web crawler. This article will be one of the first studies that investigate OCRs helpfulness based on the central cues in the text of the review. In addition, this research will be the first study that applied the support vector machine as a machine learning method to analyze the text of OCRs

The Low Prevalence of Hepatitis C Virus and Human Immunodeficiency Virus Coinfection and Hepatitis C Virus Mono-Infection Among Methadone Toxicity Patients

the incidence of Hepatitis C Virus (HCV)and Human Immunodeficiency Virus(HIV) coinfection in People Who InjectDrugs (PWIDs) is a public health issue; itpresents various contentions to the healthcareproviders. Although antiretroviral therapy improvedthe life expectancy of HIV-infected people, HCV-relatedmortality turned into a greater concern among these individuals[1]. AccFurthermore, they mentioned, “injectingdrug users in the Taipei methadone maintenancetreatment program had a very high prevalence of HIV/HBV coinfection and HCV mono-infection”[2].Besides, a systematic review and meta-analysis resultssuggested a high frequency of HIV/HBV coinfection(>80%) in Intravenous (IV) drug users [3]. Althoughthe incidence of HIV among IV drug users has beendecreased, HCV is still endemic in this population [4].We aimed to estimate HCV/HIV coinfection frequencyand its related risk factors among methadone poisonedpatients who were admitted to the Loghman Hakim poisoningcenter between March 2012 and March 2017.Loghman-Hakim Hospital is a unique poisoning referralcenter in Tehran, Iran, that admits patients from all citiesin Tehran Province, Iran. Annually, around 20000 hospitalizedpatients are observed and treated in this center,with 80-100 patients daily turn-over.The required data were collected using a questionnaire,clinical examinations, and laboratory findings. The patientswith a history of infectious diseases, like hepatitisB or C, HIV, and IV drug consumption, were excludedfrom the present research. The obtained blood sampleswere screened for antibodies to HCV and HIV using acommercially available Enzyme-Linked ImmunosorbentAssay (ELISA). Furthermore, the relevant urine sampleswere analyzed for the presence of methadone with a rapidtest. Among 200 participants, 134 (67%) were male, and66 (33%) were female with the age range of 1 to 83 years.The methadone serum levels of 129 (64.5%) patients werepositive, 39 (19.5%) were negative, and 32 (16%) patientswere not examined due to the short duration of hospitalization(i.e. <2 days). Underlying diseases, such as noncommunicablediseases (11%), psychotic disorders (1.5%), andrespiratory disease (3.5%) were detected in 30 cases. ReactiveHCV-antibodies, active HIV-antibodies, and HIV/HCV coinfection were observed in 10 (5%), 2 (1%), and 2(1%) of the study subjects, respectively. Figure 1 shows theprevalence of HCV and HIV infection by gender and age

A Recommender System for Online Consumer Reviews

Online consumer reviews have helped consumers to increase their knowledge about different products/services. While most previous studies try to provide general models that predict performance of online reviews, this study notes that different people look for different types of reviews. Hence, there is a need for developing a system that that is able to sort reviews differently for each user based on the ratings they previously assigned to other reviews. Using a design science approach, we address the above need by developing a recommender system that is able to predict the perceptions of each user regarding helpfulness of a specific review. In addition to addressing the sorting problem, this study also develops models that extract objective information from the text of online reviews including utilitarian cues, hedonic cues, product quality, service quality, price, and product comparison. Each of these characteristics may also be used for sorting and filtering online reviews