8 research outputs found

    The Effects of Social Distancing on Electricity Demand Considering Temperature Dependency

    No full text
    To mitigate the spread of the Novel Coronavirus (COVID-19), governments around the world have imposed social distancing policies ranging from minor social activity suspensions to full curfews. These social distancing policies have altered electricity consumption behaviors in numerous countries. Many governments imposed strict social distancing policies during a temperature transition season where the impacts of temperature variations are particularly important for the operation of the electric grid. This paper studies how strict social distancing policies affect the relationship between electricity demand and ambient temperature. We first review the expected short- and long-term impacts of social distancing on the electricity demand. We then present a case study on the electricity demand of the Kingdom of Saudi Arabia during strict social distancing policies. The results of this case study suggest that strict social distancing policies result in a stronger correlation between temperature and electricity demand compared to previous years. Additionally, we observe a reduction in the time required for the electricity demand to respond to temperature changes. Power system regulators can use the results in this paper to better design energy policies. The results can also be used by power system operators to more accurately forecast electricity demands and avoid inefficient and insecure operation of the electric grid

    Efficacy of povidone-iodine nasal rinse and mouth wash in COVID-19 management: a prospective, randomized pilot clinical trial (povidone-iodine in COVID-19 management)

    No full text
    Abstract Objectives/Hypothesis To assess the efficacy of 0.23% povidone-iodine (PVP-I) nasal rinses and mouth washes on detectability of the coronavirus disease 2019 (COVID-19) virus and cycle threshold (Ct) values in nasopharyngeal swabs. Study design This was an open-label, prospective, randomized, placebo-controlled clinical trial. Setting The study was conducted in King Saud University Medical City, Riyadh, Saudi Arabia, from August 2021 to July 2022. Methods Participants diagnosed with SARS-CoV-2 were randomly assigned to one of three groups, with participants receiving either 0.23% PVP-I, 0.9% normal saline (NS) nasal rinses and mouth washes, or no intervention (control group). Nasopharyngeal swabs were taken 4, 8, 12, and 18 days after the first swab to measure the detectability of the virus and the Ct. Results A total of 19 participants were involved in this study. The mean viral survival was 9.8, 12, and 12.6 days for the PVP-I, NS, and control groups, respectively, with a statistically significant difference (p = 0.046). The Ct mean values were 23 ± 3.4, 23.5 ± 6.3, and 26.3 ± 5.9 at the time of recruitment and 25.2 ± 3.5, 15 ± 11.7, and 26.9 ± 6.4 after 4 days for the PVP-I, NS, and control groups, respectively. Conclusions When used continuously at a concentration of 0.23%, PVP-I showed promising results in terms of decreasing the pandemic burden by reducing the period of infectiousness and viral load. However, the use of PVP-I did not result in significantly different changes in the quality-of-life parameters in recently vaccinated and mild COVID-19 patients

    If It Looks Like a Spammer and Behaves Like a Spammer, It Must Be a Spammer

    No full text
    Spam in online social networks (OSNs) is a systemic problem that imposes a threat to these services in terms of undermining their value to advertisers and potential investors, as well as negatively affecting users’ engagement. As spammers continuously keep creating newer accounts and evasive techniques upon being caught, a deeper understanding of their spamming strategies is vital to the design of future social media defense mechanisms. In this work, we present a unique analysis of spam accounts in OSNs viewed through the lens of their behavioral characteristics. Our analysis includes over 100 million messages collected from Twitter over the course of 1 month. We show that there exist two behaviorally distinct categories of spammers and that they employ different spamming strategies. Then, we illustrate how users in these two categories demonstrate different individual properties as well as social interaction patterns. Finally, we analyze the detectability of spam accounts with respect to three categories of features, namely content attributes, social interactions, and profile properties

    Adverse Responses following Exposure to Subtoxic Concentrations of Zinc Oxide and Nickle Oxide Nanoparticles in the Raw 264.7 Cells

    No full text
    The incorporation of engineered nanomaterials (ENMs) in biomedical and consumer products has been growing, leading to increased human exposure. Previous research was largely focused on studying direct ENM toxicity in unrealistic high-exposure settings. This could result in overlooking potential adverse responses at low and subtoxic exposure levels. This study investigated adverse cellular outcomes to subtoxic concentrations of zinc oxide (ZnONPs) or nickel oxide (NiONPs) nanoparticles in the Raw 264.7 cells, a macrophage-like cell model. Exposure to both nanoparticles resulted in a concentration-dependent reduction of cell viability. A subtoxic concentration of 6.25 ”g/mL (i.e., no observed adverse effect level) was used in subsequent experiments. Exposure to both nanoparticles at subtoxic levels induced reactive oxygen species generation. Cellular internalization data demonstrated significant uptake of NiONPs, while there was minimal uptake of ZnONPs, suggesting a membrane-driven interaction. Although subtoxic exposure to both nanoparticles was not associated with cell activation (based on the expression of MHC-II and CD86 surface markers), it resulted in the modulation of the lipopolysaccharide-induced inflammatory response (TNFα and IL6), and cells exposed to ZnONPs had reduced cell phagocytic capacity. Furthermore, subtoxic exposure to the nanoparticles distinctly altered the levels of several cellular metabolites involved in cell bioenergetics. These findings suggest that exposure to ENMs at subtoxic levels may not be devoid of adverse health outcomes. This emphasizes the importance of establishing sensitive endpoints of exposure and toxicity beyond conventional toxicological testing

    Synthesis, Characterization, and Toxicity Assessment of Zinc Oxide-Doped Manganese Oxide Nanoparticles in a Macrophage Model

    No full text
    The doping of engineered nanomaterials (ENMs) is a key tool for manipulating the properties of ENMs (e.g., electromagnetic, optical, etc.) for different therapeutic applications. However, adverse health outcomes and the cellular biointeraction of doped ENMs, compared to undoped counterparts, are not fully understood. Previously, we have shown that doping manganese oxide nanoparticles with ZnO (ZnO-MnO2 NPs) improved their catalytic properties. In this study, we assessed the toxicity of ZnO-MnO2 NPs in Raw 264.7 cells. NPs were prepared via an eco-friendly, co-precipitation method and characterized by several techniques, including transmission and scanning electron microscopy, X-ray diffraction, and Fourier transform infrared. The physicochemical properties of ZnO-MnO2 NPs, including size, morphology, and crystalline structure, were almost identical to MnO2 NPs. However, ZnO-MnO2 NPs showed slightly larger particle aggregates and negative charge in cell culture media. Exposure to ZnO-MnO2 NPs resulted in lower toxicity based on the cell viability and functional assay (phagocytosis) data. Exposure to both NPs resulted in the activation of the cell inflammatory response and the generation of reactive oxygen species (ROS). Despite this, exposure to ZnO-MnO2 NPs was associated with a lower toxicity profile, and it resulted in a higher ROS burst and the activation of the cell antioxidant system, hence indicating that MnO2 NP-induced toxicity is potentially mediated via other ROS-independent pathways. Furthermore, the cellular internalization of ZnO-MnO2 NPs was lower compared to MnO2 NPs, and this could explain the lower extent of toxicity of ZnO-MnO2 NPs and suggests Zn-driven ROS generation. Together, the findings of this report suggest that ZnO (1%) doping impacts cellular biointeraction and the consequent toxicological outcomes of MnO2 NPs in Raw 264.7 cells

    SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

    No full text
    Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population
    corecore