Oral mucosal vaccination using integrated fiber microneedles.

The oral mucosa is an attractive site for immunization due to its accessibility and ability to elicit local and systemic immune responses. However, evaluating oral mucosal immunogenicity has proven challenging due to the physical barriers and immunological complexity of the oral mucosa. Microneedles can overcome these physical barriers, but previous work has been limited in the scope of microneedle delivery site, geometry, and release kinetics, all of which are expected to affect physiological responses. Here, we develop integrated fiber microneedle devices, an oral dosage form with tunable geometries and material configurations capable of both burst and sustained release to controlled depths in the oral mucosa. Integrated fiber microneedles administered to either the buccal or sublingual mucosa result in seroconversion and antigen-specific interferon-γ secretion in splenocytes. The dynamics and magnitude of the resulting immune response can be modulated by tuning microneedle release kinetics. Optimal microneedle geometry is site-specific, with longer microneedles eliciting greater immunogenicity in the buccal mucosa, and shorter microneedles eliciting greater immunogenicity in the sublingual mucosa. The Th1/Th2 phenotype of the resulting immune response is also dependent on integrated fiber microneedle length. Together, these results establish integrated fiber microneedles as a multifunctional delivery system for the oral mucosa and motivate further exploration using tunable delivery systems to better understand oral mucosal immunity.

Telemedicine in home-based care for COVID-19 patients.

BACKGROUND: The COVID-19 pandemic has made devastating impacts on public health and global economy. While most people experience mild symptoms, it is highly transmissible and deadly in at-risk populations. Telemedicine has the potential to prevent hospitalization and provide remote care. METHODS: This retrospective study included 336 people with COVID-19, among which 141 (42%) and 195 (58%) were in Delta and Omicron dominant groups, respectively. Patients were confirmed to have COVID-19 by PCR or rapid test and were cared for via telemedicine. Severe cases were hospitalized for more intensive treatment.  RESULTS: The majority of individuals recovered at home (97.02%), while 2.98% required hospitalization. All hospital admissions were in Delta dominant group. No deaths were reported. Delta dominant group was more likely to develop loss of taste and smell, decreased appetite and need longer treatment time than those in Omicron dominant group. CONCLUSIONS: Telemedicine is a safe measure to provide at-home care for people with COVID-19 infections caused by both Delta and Omicron variants. TRIAL REGISTRATION: This study was approved by the Institutional Review Board Committee of University of Medicine and Pharmacy at Ho Chi Minh City (IRB No: 22115-DHYD).

The environmental impact of cryptocurrencies using proof of work and proof of stake consensus algorithms: A systematic review.

A systematic literature review is conducted to investigate the environmental impact of Proof of Work (PoW) and Proof of Stake (PoS) cryptocurrencies. Due to the focus of recent research on Bitcoin, an inductive approach has been applied to analyze and cluster the findings of PoW cryptocurrencies into seven aspects that effect the environmental impact of cryptocurrencies: resources, energy consumption, carbon footprint, environmental-related social and economic aspects, policy regulation and subsidization, and electronic waste. Subsequently, interconnections and rebound effects are presented and discussed by synthesizing results from each of the seven aspects into one scenario analysis inspired by the crackdown on cryptocurrency miners in China, 2021. Furthermore, it was observed that proposed policy regulation in literature is strongly focusing on miners. As the profitability of miners globally depends on the price of the PoW cryptocurrency, researchers and policymakers are advised to focus more on investors and third-party services such as regulated exchanges. Thus, identifying and implementing policies that demotivate investment in PoW cryptocurrencies could reduce their prices and the incentive to mine. Ultimately, it was assessed that PoW cryptocurrencies, especially Bitcoin, are historically associated with an ever-increasing environmental impact. In contrary, researchers address PoS as a sustainable alternative that poses a solution to the environmental issues related to PoW.

Brain Tissue-Derived Extracellular Vesicle Mediated Therapy in the Neonatal Ischemic Brain.

Hypoxic-Ischemic Encephalopathy (HIE) in the brain is the leading cause of morbidity and mortality in neonates and can lead to irreparable tissue damage and cognition. Thus, investigating key mediators of the HI response to identify points of therapeutic intervention has significant clinical potential. Brain repair after HI requires highly coordinated injury responses mediated by cell-derived extracellular vesicles (EVs). Studies show that stem cell-derived EVs attenuate the injury response in ischemic models by releasing neuroprotective, neurogenic, and anti-inflammatory factors. In contrast to 2D cell cultures, we successfully isolated and characterized EVs from whole brain rat tissue (BEV) to study the therapeutic potential of endogenous EVs. We showed that BEVs decrease cytotoxicity in an ex vivo oxygen glucose deprivation (OGD) brain slice model of HI in a dose- and time-dependent manner. The minimum therapeutic dosage was determined to be 25 µg BEVs with a therapeutic application time window of 4-24 h post-injury. At this therapeutic dosage, BEV treatment increased anti-inflammatory cytokine expression. The morphology of microglia was also observed to shift from an amoeboid, inflammatory phenotype to a restorative, anti-inflammatory phenotype between 24-48 h of BEV exposure after OGD injury, indicating a shift in phenotype following BEV treatment. These results demonstrate the use of OWH brain slices to facilitate understanding of BEV activity and therapeutic potential in complex brain pathologies for treating neurological injury in neonates.

The Effect of Gender Body-Swap Illusions on Working Memory and Stereotype Threat.

The underrepresentation of women in technical and STEM fields is a well-known problem, and stereotype threatening situations have been linked to the inability to recruit and retain women into these fields. Virtual reality enables the unique ability to perform body-swap illusions, and research has shown that these illusions can change participant behavior. Characteristically people take on the traits of the avatar they are embodying. We hypothesized that female participants embodying male avatars when a stereotype threat was made salient would demonstrate stereotype lift. We tested our hypothesis through a between-participants user study in an immersive virtual environment by measuring working memory. Our results support that stereotype threat can be induced in an immersive virtual environment, and that stereotype lift is possible with fully-immersive body-swap illusions. Additionally, our results suggest that participants in a gender-swapped avatar without an induced stereotype threat have significantly impaired working memory; however, this impairment is lifted when a threat is made salient. We discuss possible theories as to why a body-swap illusion from a female participant into a male avatar would only increase working memory impairment when not under threat, as well as applications and future research directions. Our results offer additional insight into understanding the cognitive effects of body-swap illusions, and provide evidence that virtual reality may be an applicable tool for decreasing the gender gap in technology.

Mode transformer for miniaturized optical circuits.

A novel mode transformer was fabricated that transforms a modal area by a factor of 100. Using the mode transformer improves the efficiency of mode transformation by an order of magnitude compared with that when no mode transformer is used. With this mode transformer, input-output coupling of miniaturized, on-chip integrated optical circuits to external optical fibers is achieved with low loss. The mode transformer's design, fabricated in silicon, is scalable to virtually any waveguide size, facilitating continuous miniaturization in silicon optoelectronics.