On the Security of Millimeter Wave Vehicular Communication Systems using Random Antenna Subsets

Millimeter wave (mmWave) vehicular communica tion systems have the potential to improve traffic efficiency and safety. Lack of secure communication links, however, may lead to a formidable set of abuses and attacks. To secure communication links, a physical layer precoding technique for mmWave vehicular communication systems is proposed in this paper. The proposed technique exploits the large dimensional antenna arrays available at mmWave systems to produce direction dependent transmission. This results in coherent transmission to the legitimate receiver and artificial noise that jams eavesdroppers with sensitive receivers. Theoretical and numerical results demonstrate the validity and effectiveness of the proposed technique and show that the proposed technique provides high secrecy throughput when compared to conventional array and switched array transmission techniques

Molnupiravir and risk of post-acute sequelae of covid-19: Cohort study

OBJECTIVE: To examine whether treatment with the antiviral agent molnupiravir during the first five days of SARS-CoV-2 infection is associated with reduced risk of post-acute adverse health outcomes. DESIGN: Cohort study. SETTING: US Department of Veterans Affairs. PARTICIPANTS: 229 286 participants who tested positive for SARS-CoV-2 between 5 January 2022 and 15 January 2023, had at least one risk factor for progression to severe covid-19, and survived the first 30 days after testing positive were enrolled. 11 472 participants received a prescription for molnupiravir within five days of the positive test result and 217 814 received no covid-19 antiviral or antibody treatment (no treatment group). MAIN OUTCOME MEASURES: Risks of post-acute sequelae of SARS-CoV-2 (PASC, defined based on a prespecified set of 13 post-acute sequelae), post-acute death, post-acute hospital admission, and each individual post-acute sequela between the molnupiravir group and no treatment group were examined after application of inverse probability weighting to balance the treatment and no treatment groups. Post-acute outcomes were ascertained from 30 days after the first SARS-CoV-2 positive test result until end of follow-up. Risks on the relative scale (relative risk or hazard ratio) and absolute scale (absolute risk reduction at 180 days) were estimated. RESULTS: Compared with no treatment, molnupiravir use within five days of a positive SARS-CoV-2 test result was associated with reduced risk of PASC (relative risk 0.86 (95% confidence interval 0.83 to 0.89); absolute risk reduction at 180 days 2.97% (95% confidence interval 2.31% to 3.60%)), post-acute death (hazard ratio 0.62 (0.52 to 0.74); 0.87% (0.62% to 1.13%)), and post-acute hospital admission (0.86 (0.80 to 0.93); 1.32% (0.72% to 1.92%)). Molnupiravir was associated with reduced risk of eight of the 13 post-acute sequelae: dysrhythmia, pulmonary embolism, deep vein thrombosis, fatigue and malaise, liver disease, acute kidney injury, muscle pain, and neurocognitive impairment. Molnupiravir was also associated with reduced risk of PASC in people who had not received a covid-19 vaccine, had received at one or two vaccine doses, and had received a booster dose, and in people with primary SARS-CoV-2 infection and reinfection. CONCLUSIONS: In people with SARS-CoV-2 infection and at least one risk factor for progression to severe covid-19, compared with no treatment, molnupiravir use within five days of infection was associated with reduced risk of PASC in people who had not received a covid-19 vaccine, had received one or two vaccine doses, and had received a booster dose, and in those with primary SARS-CoV-2 infection and reinfection. Among people at high risk of progression to severe covid-19, molnupiravir use within five days of SARS-CoV-2 infection may be a viable approach to reduce the risk of PASC

ALGAE TO BIODIESEL

In the spring of 2010, a CBE 459 design team focused on cultivating algae with the SimgaeTM Algal Biomass Production System, extracting algal lipids using OriginOilTM single-step extraction technology, and converting lipids into green diesel fuel. It was determined that the process was profitable, but required a staggering capital investment of 2.8 billion dollars. In the past year, both public and private institutions have joined the race to produce biofuels from an algal feedstock in an economically responsible manner that is by maintaining profitability while minimizing high capital costs. The intention of this report is to contribute to the global discourse on alternative-fuels and to reevaluate the promise of algae as a renewable resource for alternative fuels in light of the latest research and technological advances. The algae-to-biofuel venture was segmented into three modules: algal cultivation, lipid extraction and lipid processing. Each module was studied thoroughly and several strategies were proposed for the reduction of its associated fixed, capital and variable costs. As contrasted with a previous study, it was concluded that heterotrophic algal cultivation and transesterification lipid- processing technologies would improve the efficiency and reduce the total capital investment. Once each module was designed in detail, the three segments were stitched together to perform an overall economic analysis. Based on the current market price of $3.30 per gallon for pure biodiesel, a project life of 15 years, and a 15$1.3 billion and the Return on Investment (ROI) was determined to be 32%. Although these economic results are promising, they are based on an analysis that necessarily invoked highly uncertain postulates in the dearth of published data. For example, the kinetics used to model the lipid-processing module were based on data collected for palm oil at similar conditions, while the details of lipid-extraction energy usage for a high-density slurry were approximated on the basis of results for low-density slurry. Furthermore, it was concluded that the income from the sale of the algal biomass byproduct of lipid-extraction is a critical factor in the profitability. Based on its protein content, this report considered the use of algal biomass as animal feed and determined its economic worth accordingly. However, to ensure the economic success of biodiesel production, an additional analysis should focus on algal usage of biomass as a feedstock and confirm the safety of its use. Further analyses could examine other potential applications for the byproduct, including opportunities within the pharmaceutical and power generation industries. Overall, in order to convince investors that the attractive economics published in this report may be translated into actual earnings, it is critical to move beyond modeling. Pilot studies must be conducted in order to bolster the proposed algae-to-biodiesel venture with experimental data and identify possible pitfalls

Optimal Container Migration for Mobile Edge Computing: Algorithm, System Design and Implementation

Edge computing is a promising alternative to cloud computing for offloading computationally heavy tasks from resource-constrained mobile user devices. Placed at the edge of the network, edge computing is particularly advantageous to delay-limited applications for having a short distance to end- users. However, when a mobile user moves away from the service coverage of the associated edge server, the advantage gradually vanishes, increasing response time. Although service migration has been studied to address this problem focusing on minimizing the service downtime, both zero-downtime and the amount of traffic generated as a result of migration need further study. In this paper, an optimal live migration for containerized edge computing service is studied. This paper presents three zero-downtime migration techniques based on state duplication and state reproduction techniques, and then, proposes an optimal migration technique selection algorithm that jointly minimizes the response time and network traffic during migration. For validation and performance comparison, the proposed migration techniques are implemented on off-the-shelf hardware with Linux operating system. The evaluation results showed that compared with a naive migration, the optimal approach reduced the response time and network load by at least 74.75% and 94.79%, respectively, under considered scenarios

The endosymbiont Wolbachia rebounds following antibiotic treatment

Antibiotic treatment has emerged as a promising strategy to sterilize and kill filarial nematodes due to their dependence on their endosymbiotic bacteria, Wolbachia. Several studies have shown that novel and FDA-approved antibiotics are efficacious at depleting the filarial nematodes of their endosymbiont, thus reducing female fecundity. However, it remains unclear if antibiotics can permanently deplete Wolbachia and cause sterility for the lifespan of the adult worms. Concerns about resistance arising from mass drug administration necessitate a careful exploration of potential Wolbachia recrudescence. In the present study, we investigated the long-term effects of the FDA-approved antibiotic, rifampicin, in the Brugia pahangi jird model of infection. Initially, rifampicin treatment depleted Wolbachia in adult worms and simultaneously impaired female worm fecundity. However, during an 8-month washout period, Wolbachia titers rebounded and embryogenesis returned to normal. Genome sequence analyses of Wolbachia revealed that despite the population bottleneck and recovery, no genetic changes occurred that could account for the rebound. Clusters of densely packed Wolbachia within the worm\u27s ovarian tissues were observed by confocal microscopy and remained in worms treated with rifampicin, suggesting that they may serve as privileged sites that allow Wolbachia to persist in worms while treated with antibiotic. To our knowledge, these clusters have not been previously described and may be the source of the Wolbachia rebound