Abstract Objective A significant correlation exists between coronary artery diseases and depression. The aim of this trial was to compare the efficacy and safety of saffron versus fluoxetine in ...improving depressive symptoms of patients who were suffering from depression after performing percutaneous coronary intervention (PCI). Methods In this randomized double-blind parallel-group study, 40 patients with a diagnosis of mild to moderate depression who had undergone PCI in the last six months were randomized to receive either fluoexetine (40 mg/day) or saffron (30 mg/day) capsule for six weeks. Participants were evaluated by Hamilton depression rating scale (HDRS) at weeks 3 and 6 and the adverse events were systemically recorded. Results By the study endpoint, no significant difference was detected between two groups in reduction of HDRS scores ( P =0.62). Remission and response rates were not significantly different as well ( P =1.00 and P =0.67; respectively). There was no significant difference between two groups in the frequency of adverse events during this trial. Limitations Relatively small sample size and short observational period were the major limitations of this study. Conclusion Short-term therapy with saffron capsules showed the same antidepressant efficacy compared with fluoxetine in patients with a prior history of PCI who were suffering from depression.
In this work, we examine the changes in demand for bike-sharing platforms with the onset of the Covid-19 pandemic. Using the fixed-effects regression formulation of difference-in-differences, we ...evaluate how the demand for bike-sharing platforms changed after the first cases of Covid were discovered and after the first executive orders were implemented. Accounting for weather conditions, socio-economic characteristics, time trends, and fixed effects across cities, our findings indicate that there is an increase in daily bike-sharing trips by 22% on average after the first Covid-19 case diagnosis, and a decrease of 30% after the first executive order implementation in each municipality, using the data up to August 2020. Moreover, we observe a 22% increase in weekday-specific trip frequency after the first Covid-19 case diagnosis and a 28% decrease in weekend-specific trip frequency after the first executive order implementation. Finally, we find that there is an increase in the frequency of trips on bike-sharing platforms in more bike-friendly, transit-friendly, and pedestrian-friendly cities upon both the first Covid-19 case diagnosis and the first executive order implementation.
Do spikes in Twitter chatter about a firm precede unusual stock market trading activity for that firm? If so, Twitter activity may provide useful information about impending financial market activity ...in real-time. We study the real-time relationship between chatter on Twitter and the stock trading volume of 96 firms listed on the Nasdaq 100, during 193 days of trading in the period from May 21, 2012 to September 18, 2013. We identify observations featuring firm-specific spikes in Twitter activity, and randomly assign each observation to a ten-minute increment matching on the firm and a number of repeating time indicators. We examine the extent that unusual levels of chatter on Twitter about a firm portend an oncoming surge of trading of its stock within the hour, over and above what would normally be expected for the stock for that time of day and day of week. We also compare the findings from our explanatory model to the predictive power of Tweets. Although we find a compelling and potentially informative real-time relationship between Twitter activity and trading volume, our forecasting exercise highlights how difficult it can be to make use of this information for monetary gain.
During the last four decades, digital technologies have disrupted many industries. Car control systems have gone from mechanical to digital. Telephones have changed from sound boxes to portable ...computers. But have the firms that digitized their products and services become more valuable than firms that didn't? Here we introduce the construct of digital proximity, which considers the interdependent activities of firms linked in an economic network. We then explore how the digitization of products and services affects a company's Tobin's q-the ratio of market value over assets-a measure of the intangible value of a firm. Our panel regression methods and robustness tests suggest the positive influence of a firm's digital proximity on its Tobin's q. This implies that firms able to come closer to the digital sector have increased their intangible value compared to those that have failed to do so. These findings contribute a new way of measuring digitization and its impact on firm performance that is complementary to traditional measures of information technology (IT) intensity.
Background In addition to their educational role, resilient schools have a good capacity in response to disasters. Due to the large student population, the schools can be a safe and secure ...environment during disasters, in addition to maintaining their performance after. Given the role and importance of the schools, the impact of culture and environment on resilience, without any indigenous and comprehensive tool for measuring the resilience in Iran, the study aimed to design and psychometrically evaluate the measurement tools. Method This study was conducted using a mixed-method sequential explanatory approach. The research was conducted in two main phases of production on items based on hybrid model and the psychometric evaluation of the tool. The second phase included validity (formal, content and construction) and reliability (multiplex internal similarity, consistency and reliability). Result The integration of systematic and qualitative steps resulted in entering 91 items into the pool of items. After formal and content validity, 73 items remained and 44 were omitted in exploratory factor analysis. A questionnaire with 5 factors explained 52.08% of total variance. Finally, after the confirmatory factor analysis, the questionnaire was extracted with 29 questions and 5 factors including "functional", "architectural", "equipment", "education" and "safety". Internal similarity and stability in all factors were evaluated as good. Conclusion The result showed that the 29-item questionnaire of school resilience in emergencies and disasters is valid and reliable, that can be used to evaluate school resilience. On the other hand, the questionnaire on assessment of school resilience in disasters enables intervention to improve its capacity.
Over the past few decades, the prevalence of Diabetes Mellitus (DM) has risen rapidly in Iran and other low and middle-income countries. We investigated the prevalence of DM, pre-diabetes, ...undiagnosed and uncontrolled diabetes and its relationship with some associated socioeconomic factors in the Yazd Greater Area in Iran.
Yazd Health Study is a longitudinal study conducted to determine the prevalence of non-communicable disease and related risk factors. In a two-step cluster sampling, 10,000 adults aged 20-69 years (200 clusters) were selected. In the recruitment phase, DM was considered if the patients had been either diagnosed DM by a physician or had fasting blood glucose ≥ 126 mg/dL. Chi square test was used for categorical variables to evaluate the differences and logistic regression model was applied to determine the predictors of diabetes.. P-value < 0.05 considered statistically significant.
Of the 9965 individuals recruited, the crude self-reported prevalence of DM was 14.1% (95% CI: 13.4-14.7). The prevalence was higher in women than men (15.6 vs.12.4%), significantly. The age-standardized prevalence of DM was 8%. The prevalence was 14.9% in Yazd local people and 8.6% in those residents migrated from other provinces (P < 0.0001). We showed a significant association between DM prevalence and age, education, marital status, unemployment, insurance status, and positive family history (P < 0.0001). The prevalence of DM diagnosed by phycisians was 16.1% in participants (age-standardized prevalence: 8.3%). The subset analysis showed that 4.8% of patients were not aware of their disease. The prevalence of pre-diabetes was 25.8%. Of those with diabetes, 58.3% were not adequately controlled, which is not statistically significant with socio-economic status.
The current study showed a high prevalence of DM in Yazd Greater Area which is closely related to some socio-demographic factors. The high prevalence of pre-diabetes is alarming. Effective strategies for DM prevention should be introduced. The majority of people with diabetes are aware, but half of them are not controlled. The ineffective care plan currently in use, should be reviewed. Patients needs to be encouraged to improve their lifestyle. Active follow-up of patients is recommended to ensure continuity of care.
Many internet platforms that collect behavioral big data use it to predict user behavior for internal purposes and for their business customers (e.g., advertisers, insurers, security forces, ...governments, political consulting firms) who utilize the predictions for personalization, targeting, and other decision-making. Improving predictive accuracy is therefore extremely valuable. Data science researchers design algorithms, models, and approaches to improve prediction. Prediction is also improved with larger and richer data. Beyond improving algorithms and data, platforms can stealthily achieve better prediction accuracy by pushing users’ behaviors towards their predicted values, using behavior modification techniques, thereby demonstrating more certain predictions. Such apparent “improved” prediction can result from employing reinforcement learning algorithms that combine prediction and behavior modification. This strategy is absent from the machine learning and statistics literature. Investigating its properties requires integrating causal with predictive notation. To this end, we incorporate Pearl’s causal do(.) operator into the predictive vocabulary. We then decompose the expected prediction error given behavior modification and identify the components impacting predictive power. Our derivation elucidates implications of such behavior modification to data scientists, platforms, their customers, and the humans whose behavior is manipulated. Behavior modification can make users’ behavior more predictable and even more homogeneous; yet this apparent predictability might not generalize when business customers use predictions in practice. Outcomes pushed towards their predictions can be at odds with customers’ intentions, and harmful to manipulated users.
In this paper, we examine how the competitive industry environment shapes the way that digital strategic posture (defined as a focal firm's degree of engagement in a particular class of digital ...business practices relative to the industry norm) influences firms' realized digital business strategy. We focus on two forms of digital strategy: general IT investment and IT outsourcing investment. Drawing from prior literature on determinants of IT activity and competitive dynamics, we argue that three elements of the industry environment determine whether digital strategic posture has an increasingly convergent or divergent influence on digital business strategy. By divergent influence, we mean an influence that leads to spending substantially more or less on a particular strategic activity than industry norms. We predict that a digital strategic posture (difference from the industry mean) has an increasingly divergent effect on digital business strategy under higher industry turbulence, while having an increasingly convergent effect on digital business strategy under higher industry concentration and higher industry growth. The study uses archival data for 400 U.S.-based firms from 1999 to 2006. Our findings imply that digital business strategy is not solely a matter of optimizing firm operations internally or of responding to one or two focal competitors, but also arises strikingly from awareness and responsiveness to the digital business competitive environment. Collectively, the findings provide insights on how strategic posture and industry environment influence firms' digital business strategy.
Strategic management of the wastage produced due to earthquakes has faced many challenges over the recent decade. Thus, the present study seeks to identify and explain the challenges in earthquake ...wastage strategic management.
The present qualitative study has been steered through a content analysis approach and conducted using semi-structured interviews and a purposive selection of 17 professors, experts, and managers experienced in the field of waste management in Kermanshah and Varzaghan-Ahar earthquakes over 2020-2021. Besides, the interviews were initially categorized using MAXQDA18 software.
Analysis of the experiences and perception regarding the changes in strategic management of wastage produced due to Kermanshah and Varzaghan-Ahar earthquakes revealed 418 codes, 97 subcategories, 33 categories, and 8 main categories including management and leadership, organizational culture, planning, organizational learning, employee management, rules and regulations, resource management, and procedure management.
Strategic waste management has not been implemented in a coherent, integrated, and well-planned manner in the cases of the Kermanshah and Varzaghan-Ahar earthquakes. The challenges of strategic waste management turned out to be due to various reasons which will result in many issues in achieving the goals and selecting the suitable method for resource and procedure management should they not be managed well. Hence, policymakers, managers, and executors in the field of crisis management and waste management in disasters -specifically earthquakes- must take the necessary measures to remove these barriers.
How should digital platforms engage with and invest in their online communities to shape innovation and knowledge contributions from members in their platform ecosystems? This is an important ...question because user contributions are important drivers of technological progress and business value. We examine the effect of platform sponsors’ investments in online communities on user knowledge contributions, using fine-grained longitudinal data from a leading enterprise software vendor’s community network. We focus on the sponsor practice of knowledge seeding, in which its employees provide free technical support by answering questions posted in discussion forums. We define user knowledge contribution as peer-evaluated, quality-weighted solutions that community members provide to help resolve the questions their peers raise. We show that the platform sponsor’s investments in knowledge seeding have a positive, significant association with user knowledge contribution. We also find temporal and geographical variations in returns on the sponsor’s knowledge investments. Specifically, returns (i.e., amount of user contribution that is stimulated) decrease with the age of the community, consistent with the observation that the most active contributors are lead users who tend to join the community early. In addition, returns vary across different countries, such that greater returns are realized when the investment is made in countries with higher levels of information technology (IT) infrastructure, partly because country-level IT infrastructure may be associated with greater absorptive capacity of these countries. We discuss the implications for research and practice.
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