Self-propulsion via slipping: Frictional swimming in multilegged locomotors.

Locomotion is typically studied either in continuous media where bodies and legs experience forces generated by the flowing medium or on solid substrates dominated by friction. In the former, centralized whole-body coordination is believed to facilitate appropriate slipping through the medium for propulsion. In the latter, slip is often assumed minimal and thus avoided via decentralized control schemes. We find in laboratory experiments that terrestrial locomotion of a meter-scale multisegmented/legged robophysical model resembles undulatory fluid swimming. Experiments varying waves of leg stepping and body bending reveal how these parameters result in effective terrestrial locomotion despite seemingly ineffective isotropic frictional contacts. Dissipation dominates over inertial effects in this macroscopic-scaled regime, resulting in essentially geometric locomotion on land akin to microscopic-scale swimming in fluids. Theoretical analysis demonstrates that the high-dimensional multisegmented/legged dynamics can be simplified to a centralized low-dimensional model, which reveals an effective resistive force theory with an acquired viscous drag anisotropy. We extend our low-dimensional, geometric analysis to illustrate how body undulation can aid performance in non-flat obstacle-rich terrains and also use the scheme to quantitatively model how body undulation affects performance of biological centipede locomotion (the desert centipede Scolopendra polymorpha) moving at relatively high speeds (∼0.5 body lengths/sec). Our results could facilitate control of multilegged robots in complex terradynamic scenarios.

Probing Hydrodynamic Fluctuation-Induced Forces with an Oscillating Robot.

We study the dynamics of an oscillating, free-floating robot that generates radially expanding gravity-capillary waves at a fluid surface. In open water, the device does not self-propel; near a rigid boundary, it can be attracted or repelled. Visualization of the wave field dynamics reveals that when near a boundary, a complex interference of generated and reflected waves induces a wave amplitude fluctuation asymmetry. Attraction increases as wave frequency increases or robot-boundary separation decreases. Theory on confined gravity-capillary wave radiation dynamics developed by Hocking in the 1980s captures the observed parameter dependence due to these "Hocking fields." The flexibility of the robophysical system allows detailed characterization and analysis of locally generated nonequilibrium fluctuation-induced forces [M. Kardar and R. Golestanian, Rev. Mod. Phys. 71, 1233 (1999)RMPHAT0034-686110.1103/RevModPhys.71.1233].

Young Adults' Exposure to and Engagement With Tobacco-Related Social Media Content and Subsequent Tobacco Use.

INTRODUCTION: Nicotine/tobacco social media content may increase young people's risk for use. This study examined prospective associations between exposure to and engagement with nicotine/tobacco-related social media content and nicotine/tobacco use among young adults. AIMS AND METHODS: Young adults (N = 2080) originally recruited from Southern California high schools for a prospective cohort study reported frequency of viewing and posting nicotine/tobacco content on four social media platforms (Facebook, Instagram, Twitter, and YouTube). Participants also reported frequency of seeing nicotine/tobacco posts from friends, seeing nicotine/tobacco posts from influencers or celebrities, and liking nicotine/tobacco posts. Within subsamples of nicotine/tobacco never users (n = 794), past users (n = 897) and current users (n = 389), analyses examined associations of baseline (May-October 2020) social media content exposure and engagement with follow-up (January-June 2021) tobacco use initiation (among never users), resumption (among past users), and continuation (among current users), adjusting for sociodemographic and socioenvironmental characteristics. RESULTS: Never users who saw nicotine/tobacco posts from friends (Adjusted Odds Ratio [AOR] = 2.91 [95% Confidence Interval [CI]: 1.46, 5.82], p = .002) or from celebrities or influencers (AOR = 2.77 [1.32, 5.84], p = .007) were significantly more likely to initiate nicotine/tobacco use than their peers. Among past users, posting nicotine/tobacco content at baseline was associated with use resumption (AOR = 1.77 [1.12, 2.80], p = .014). Content exposure and engagement were not associated with nicotine/tobacco use continuation among current users (p-values > .05). CONCLUSIONS: Seeing nicotine/tobacco posts from friends, influencers, or celebrities was associated with greater odds of tobacco use initiation, but not resumption or continuation, 6 months later. Young adults with past nicotine/tobacco use who post about nicotine/tobacco may be at elevated risk for resuming use. IMPLICATIONS: Young adults with exposure to nicotine/tobacco social media content were more likely than their peers to initiate nicotine/tobacco use 6 months later. Past nicotine/tobacco users who reported posting about nicotine/tobacco on social media at baseline were more likely than their peers to resume nicotine/tobacco use. Among young adults with current nicotine/tobacco use at baseline, social media activity did not predict odds of nicotine/tobacco use continuation at follow-up. Nicotine/tobacco content on social media should be restricted to reduce young people's chances of nicotine/tobacco use initiation or resumption.

Hepatitis C virus NS5A and core protein induce fibrosis-related genes regulation on Huh7 cells through activation of LX2 cells.

INTRODUCTION AND OBJECTIVES: Liver fibrosis remains a complication derived from a chronic Hepatitis C Virus (HCV) infection even when it is resolved, and no liver antifibrotic drug has been approved. Molecular mechanisms on hepatocytes and activation of hepatic stellate cells (HSCs) play a central role in liver fibrogenesis. To elucidate molecular mechanisms, it is important to analyze pathway regulation during HSC activation and HCV infection. MATERIALS AND METHODS: We evaluate the fibrosis-associated molecular mechanisms during a co-culture of human HSCs (LX2), with human hepatocytes (Huh7) that express HCV NS5A or Core protein. We evaluated LX2 activation induced by HCV NS5A or Core expression in Huh7 cells during co-culture. We determined a fibrosis-associated gene expression profile in Huh7 that expresses NS5A or Core proteins during the co-culture with LX2. RESULTS: We observed that NS5A induced 8.3-, 6.7- and 4-fold changes and that Core induced 6.5-, 1.8-, and 6.2-fold changes in the collagen1, TGFß1, and timp1 gene expression, respectively, in LX2 co-cultured with transfected Huh7. In addition, NS5A induced the expression of 30 genes while Core induced 41 genes and reduced the expression of 30 genes related to fibrosis in Huh7 cells during the co-culture with LX2, compared to control. The molecular pathways enriched from the gene expression profile were involved in TGFB signaling and the organization of extracellular matrix. CONCLUSIONS: We demonstrated that HCV NS5A and Core protein expression regulate LX2 activation. NS5A-induced LX2 activation, in turn, regulates diverse fibrosis-related gene expression at different levels in Huh7, which can be further analyzed as potential antifibrotic targets during HCV infection.

PopHumanVar: an interactive application for the functional characterization and prioritization of adaptive genomic variants in humans.

Adaptive challenges that humans faced as they expanded across the globe left specific molecular footprints that can be decoded in our today's genomes. Different sets of metrics are used to identify genomic regions that have undergone selection. However, there are fewer methods capable of pinpointing the allele ultimately responsible for this selection. Here, we present PopHumanVar, an interactive online application that is designed to facilitate the exploration and thorough analysis of candidate genomic regions by integrating both functional and population genomics data currently available. PopHumanVar generates useful summary reports of prioritized variants that are putatively causal of recent selective sweeps. It compiles data and graphically represents different layers of information, including natural selection statistics, as well as functional annotations and genealogical estimations of variant age, for biallelic single nucleotide variants (SNVs) of the 1000 Genomes Project phase 3. Specifically, PopHumanVar amasses SNV-based information from GEVA, SnpEFF, GWAS Catalog, ClinVar, RegulomeDB and DisGeNET databases, as well as accurate estimations of iHS, nSL and iSAFE statistics. Notably, PopHumanVar can successfully identify known causal variants of frequently reported candidate selection regions, including EDAR in East-Asians, ACKR1 (DARC) in Africans and LCT/MCM6 in Europeans. PopHumanVar is open and freely available at https://pophumanvar.uab.cat.

Proximity to Cannabis Retailers and Recent Cannabis Use among a Diverse Sample of California Adolescents.

Background: As of May 2023, 23 states and Washington, DC have legalized the sale of cannabis for adults aged 21+, and 38 states, three territories, and D.C. have legalized medical cannabis. Exposure to cannabis retailers could increase adolescent cannabis use. Few studies have examined the impact of residential proximity to cannabis retailers on adolescent cannabis use, and previous findings are inconsistent. Methods: This study examined associations between proximity to cannabis retailers and past 30-day cannabis use. Data were from Project Cal Teens, a statewide survey of California adolescents regarding cannabis-related opinions/behaviors (N = 1406, mean age = 15.5 years, 48% female, 38% Hispanic/Latinx, 33% White, 15% Asian/Pacific Islander, 10% Black/African American, 5% Other/Multiracial). Participants were recruited via schools/social media in 2018-2020. Results: For every additional 5 driving miles to the nearest cannabis retailer, the risk of past 30-day cannabis use was reduced by 3.6% [IRR: 0.964; 95% CI: 0.935-0.994]. For every additional 5 miles from a licensed retailer, the risk of past 30-day cannabis use was reduced by 4.3% [IRR: 0.957; 95% CI: 0.926-0.989]. Interaction analyses revealed that among Hispanic/Latinx students, every 5 miles from a licensed retailer was associated with an 11.9% reduction in the risk of past 30-day cannabis use [IRR: 0.881; 95% CI: 0.820-0.945]. Conclusions: As the number of cannabis retailers in the U.S. increases with the continued legalization of adult cannabis use, research examining the effects of these policies on underage use is crucial. Interventions could include enforcement of zoning laws in/near residential areas to reduce accessibility of adolescents to cannabis retailers.

Antibody-dependent NK-cell and neutralizing antibody responses against the Spike protein of Wuhan-Hu-1 and Omicron BA.1 SARS-CoV-2 variants in vaccinated experienced and vaccinated naïve individuals.

Antibodies triggering Fc-mediated NK cell activity may contribute to protection against disease caused by SARS-CoV-2 infection in humans. However, how these Fc-mediated humoral responses compare between individuals displaying hybrid immunity (Vac-ex) and those fully vaccinated with no history of SARS-CoV-2 infection (Vac-n) and whether they correlate with neutralizing antibody (NtAb) responses remains largely undetermined. In this retrospective study serum samples from 50 individuals (median age, 44.5 years; range, 11-85; 25 males), 25 Vac-ex and 25 Vac-n were studied. A flow-cytometry-based antibody-mediated NK-cell activation assay was used to quantitate effector NK-cells stimulated to express LAMP1 (lysosomal associated membrane protein 1), MIP1 (Macrophage inflammatory protein 1), and interferon-γ (IFNγ); NK cells isolated from two donors (D1 and D2) were used. NtAb levels targeting the Spike protein of Wuhan-Hu-1 and Omicron BA.1 SARS-CoV-2 variants were quantitated using a SARS-CoV-2 S pseudotyped neutralization assay. Regardless of the SARS-CoV-2 variant S antigen used in the NK-cell activation assay, the frequency of NK cells stimulated to express LAMP-1, MIP1ß, and IFNγ was higher in Vac-ex compared with Vac-n (p values ranging from 0.07 to 0.006) for D1; this was only seen for BA.1 when NK cells from D2 were employed. The frequency of functional NK cells activated by antibody binding to either Wuhan-Hu-1 or Omicron BA.1 S protein was not significantly different for both VAC-ex and VAC-n. In contrast, NtAb titers against BA.1 were around 10-fold lower than that against Wuhan-Hu-1. Vac-ex displayed higher NtAb titers against both (sub)variants than Vac-n. NK-cell responses correlated poorly with NtAb titers (ρ ≤ 0.30). The data demonstrate higher cross-reactivity across variants of concern for antibodies triggering Fc-mediated NK cell than for NtAb. Moreover, Vac-Ex seemed to display more robust functional antibody responses as compared with Vac-n.

Hypoxia-induced blood-brain barrier dysfunction is prevented by pericyte-conditioned media via attenuated actomyosin contractility and claudin-5 stabilization.

The blood-brain barrier (BBB) regulates molecular and cellular entry from the cerebrovasculature into the surrounding brain parenchyma. Many diseases of the brain are associated with dysfunction of the BBB, where hypoxia is a common stressor. However, the contribution of hypoxia to BBB dysfunction is challenging to study due to the complexity of the brain microenvironment. In this study, we used a BBB model with brain microvascular endothelial cells and pericytes differentiated from iPSCs to investigate the effect of hypoxia on barrier function. We found that hypoxia-induced barrier dysfunction is dependent upon increased actomyosin contractility and is associated with increased fibronectin fibrillogenesis. We propose a role for actomyosin contractility in mediating hypoxia-induced barrier dysfunction through modulation of junctional claudin-5. Our findings suggest pericytes may protect brain microvascular endothelial cells from hypoxic stresses and that pericyte-derived factors could be candidates for treatment of pathological barrier-forming tissues.

Active and passive mechanics for rugose terrain traversal in centipedes.

Centipedes coordinate body and limb flexion to generate propulsion. On flat, solid surfaces, the limb-stepping patterns can be characterized according to the direction in which limb-aggregates propagate, opposite to (retrograde) or with the direction of motion (direct). It is unknown how limb and body dynamics are modified in terrain with terradynamic complexity more representative of these animal's natural heterogeneous environments. Here, we investigated how centipedes that use retrograde and direct limb-stepping patterns, Scolopendra polymorpha and Scolopocryptops sexspinosus, respectively, coordinate their body and limbs to navigate laboratory environments which present footstep challenges and terrain rugosity. We recorded the kinematics and measured the locomotive performance of these animals traversing two rugose terrains with randomly distributed step heights and compared the kinematics with those on a flat frictional surface. Scolopendra polymorpha exhibited similar body and limb dynamics across all terrains and a decrease in speed with increased terrain rugosity. Unexpectedly, when placed in a rugose terrain, S. sexspinosus changed the direction of the limb-stepping pattern from direct to retrograde. Further, for both species, traversal of these rugose terrains was facilitated by hypothesized passive mechanics: upon horizontal collision of a limb with a block, the limb bent and later continued the stepping pattern. Although centipedes have many degrees of freedom, our results suggest these animals negotiate limb-substrate interactions and navigate complex terrains leveraging the innate flexibility of their limbs to simplify control.

Spanish-language tobacco-related posts on Twitter: content analysis.

INTRODUCTION: Twitter data has been used to surveil public sentiment about tobacco products, however, most tobacco-related Twitter research has been conducted with English-language posts. There is a gap in the literature on tobacco-related discussions on Twitter in languages other than English. This study summarized tobacco-related discussions in Spanish on Twitter. METHODS: A set of Spanish terms reflecting electronic cigarettes (e.g., cigarillos electrónicos), cigarettes (e.g., "pitillo"), and cigars (e.g., "cigaro") were identified. A content analysis of tweets (n=1,352) drawn from 2021 was performed to examine themes and sentiment. An initial codebook was developed in English then translated to Spanish and then translated back to English by a bilingual (Spanish and English) member of the research team. Two bilingual members of the research team coded the tweets into themes and sentiment. RESULTS: Themes in the tweets included 1) product promotion (n=168, 12.4%), 2) health warnings (n=161, 11.9%), 3) tobacco use (n=136, 10.1%), 4) health benefits of vaping (n=58, 4.3%), 5) cannabis use (n=50, 3.7%), 6) cessation (n=47, 3.5%), 7) addiction (n=33, 2.4%), 8) policy (n=27, 2.0%), and 9) polysubstance use (n=12, 0.9%). Neutral (n=955, 70.6%) was the most common category of sentiment observed in the data. CONCLUSIONS: Tobacco products are discussed in multiple languages on Twitter and can be summarized by bilingual research teams. Future research should determine if Spanish-speaking individuals are frequently exposed to pro-tobacco content on social media and if such exposure increases susceptibility to use tobacco among never users or sustained use among current users. IMPLICATIONS: Spanish-language pro-tobacco content exists on Twitter, which has implications for Spanish-speaking individuals who may be exposed to this content. Spanish-language pro-tobacco-related posts may help normalize tobacco use among Spanish-speaking populations. As a result, anti-tobacco tweets in Spanish may be necessary to counter areas of the online environment that can be considered pro-tobacco.

Characteristics associated with attitudes and behaviors towards mask wearing during the COVID-19 pandemic: The Trojan Pandemic Response Initiative.

BACKGROUND: Attitudes and behaviors towards mask wearing may influence the ability to reduce transmission of COVID-19 and other diseases. METHODS: University students, staff, and faculty (N = 9653) responded to an email invitation to complete electronic surveys (November 2021 and April 2022). Surveys included 19 items measuring attitudes and behaviors towards mask wearing from the Understanding America Study. Linear mixed models including variables for sex, age group, division, race and ethnicity, political affiliation, and history of COVID-19, were used to estimate the mean difference of the mean score for attitudes and behavior between Time 1 (November 2021) and Time 2 (April 2022). RESULTS: Participants were mostly female (62.1%), students (70.6%), White (39.5%) and Asian (34.7%). More than half identified their political affiliation as Democrat (65.5%). Characteristic variable-by-time interactions for difference in mean mask attitude scores difference were significant at Time 1 (T1) and Time 2 (T2) between Black and White participants (B = 0.18 (0.05), 95% CI: 0.07, 0.28, p = 0.001), Asian and White participants (B = 0.07 (0.02), 95% CI: 0.03-0.12, p = 0.001), participants with self-reported history of COVID-19 and no history of COVID-19 (B= -0.13 (0.02), 95% CI: -0.07, -0.18, p < 0.0001), females and males (B = 0.07 (0.02), 95% CI: 0.03, 0.11, p = 0.001), Republicans and Democrats (B= -0.18 (0.04), 95%CI: -0.26, -0.10, p < 0.0001) and Independents and Democrats (B= -0.10 (0.03), 95%CI: -0.15, -0.05, p < 0.0001). Mean difference in mean scores for mask behaviors at Time and Time 2 were significant between participants with COVID-19 and participants who did not have COVID-19 (B= -0.12 (0.04), 95% CI: -0.19, -0.04, p = 0.004), students compared to faculty and staff (B=-0.22 (0.05), -0.32, -0.12, p < 0.0001), between Republicans and Democrats (B-= -0.16 (0.07), 95% CI: -0.28, -0.03, p = 0.020, and between Independents and Democrats (B=-0.08 (0.04), 95% CI: -0.16, -0.002, p = 0.04). CONCLUSION: Race and ethnicity, political affiliation, and division may affect attitudes and behaviors in mask wearing. Further investigation into how characteristics influence public health measures such as mask wearing is needed to contain the spread of the COVID-19 virus, other infectious diseases, and future pandemics.

Trust in science and scientists among university students, staff, and faculty of a large, diverse university in Los Angeles during the COVID-19 pandemic, the Trojan Pandemic Response Initiative.

BACKGROUND: Mistrust in science and scientists may adversely influence the rate of COVID-19 vaccination and undermine public health initiatives to reduce virus transmission. METHODS: Students, staff and faculty responded to an email invitation to complete an electronic survey. Surveys included 21-items from the Trust in Science and Scientists Inventory questionnaire. Responses were coded so higher scores indicated a higher trust in science and scientists, A linear regression model including sex, age group, division, race and ethnicity, political affiliation, and history of COVID-19, was used to determine variables significantly associated with trust in science and scientists scores at the p < 0.05 level. RESULTS: Participants were mostly female (62.1%), Asian (34.7%) and White (39.5%) and students (70.6%). More than half identified their political affiliation as Democrat (65%). In the final regression model, all races and ethnicities had significantly lower mean trust in science and scientists scores than White participants [Black ([Formula: see text]= -0.42, 95% CI: -0.55, -0.43, p < 0.001); Asian ([Formula: see text]= -0.20, 95% CI: -0.24, -0.17, p < 0.001); Latinx ([Formula: see text]= -0.22, 95% CI: -0.27, -0.18, p < 0.001); Other ([Formula: see text]= -0.19, 95% CI: -0.26, -0.11, p < 0.001)]. Compared to those identifying as Democrat, all other political affiliations had significantly lower mean scores. [Republican ([Formula: see text] =-0.49, 95% CI: -0.55, -0.43, p < 0.0001); Independent ([Formula: see text] =-0.29, 95% CI: -0.33, -0.25, p < 0.0001); something else ([Formula: see text] =-0.19, 95% CI: -0.25, -0.12, p < 0.0001)]. Having had COVID-19 ([Formula: see text]= -0.10, 95% CI: -0.15, -0.06, p < 0.001) had significantly lower scores compared to those who did not have COVID-19. CONCLUSION: Despite the setting of a major research University, trust in science is highly variable. This study identifies characteristics that could be used to target and curate educational campaigns and university policies to address the COVID19 and future pandemics.

Surveying Adolescents During a Pandemic: Comparison of Adolescents Recruited via Social Media vs. Schools.

School-based surveys of adolescents can be logistically difficult and exclude students who do not attend school. Social media recruitment could be a promising strategy to recruit representative samples of adolescents. However, few studies have compared adolescent survey data collected via different methodologies. Our team was conducting a school-based survey when the COVID-19 pandemic closed all schools, necessitating a shift to online adolescent recruitment. To achieve our goal of obtaining a sample of high school students throughout California, we placed ads on social media. We compared the adolescents recruited in schools with those recruited on social media on demographic characteristics, mental health, and substance use. The sample of students recruited in schools (N = 737) and adolescents recruited via social media (N = 953) did not differ significantly on gender or substance use. However, compared with school-based recruitment, social media recruitment yielded a higher proportion of boys, whites, and Asians and a lower proportion of girls, Hispanic/Latinx adolescents, and those who spoke other languages at home. The social media sample had significantly higher levels of depression and anxiety symptoms and perceived stress than the school-based sample. Results indicate that social media can be useful for recruiting adolescents for survey research, especially if strategies such as Spanish-language social media ads are used to recruit and consent Hispanic/Latinx adolescents and those with non-English-speaking parents. This method could potentially replace school-based surveys in cases where schools are unwilling to participate in research, or it could be used to supplement school-based samples. Advantages and disadvantages of both methods are discussed.

COVID-19 Testing in Schools: Perspectives of School Administrators, Teachers, Parents, and Students in Southern California.

BACKGROUND: School-based COVID-19 testing is a potential strategy to facilitate the safe reopening of schools that have been closed due to the pandemic. This qualitative study assessed attitudes toward this strategy among four groups of stakeholders: school administrators, teachers, parents, and high school students. METHODS: Focus groups and interviews were conducted in Los Angeles from December 2020 to January 2021 when schools were closed due to the high level of COVID transmission in the community. RESULTS: Findings indicated similarities and differences in attitudes toward in-school COVID-19 testing. All groups agreed that frequent in-school COVID-19 testing could increase the actual safety and perceived safety of the school environment. School administrators expressed pessimism about the financial cost and logistics of implementing a testing program. Parents supported frequent testing but expressed concerns about physical discomfort and stigma for students who test positive. Teachers and parents noted that testing would prevent parents from sending sick children to school. Students were in favor of testing because it would allow them to return to in-person school after a difficult year of online learning. CONCLUSION: In-school COVID-19 testing could be a useful component of school reopening plans and will be accepted by stakeholders if logistical and financial barriers can be surmounted and stigma from positive results can be minimized.

Cultural Stress Profiles: Describing Different Typologies of Migration Related and Cultural Stressors among Hispanic or Latino Youth.

Youth of immigrant origin vary across their families' migration history (e.g., country of heritage, reasons for migration, etc.) and in the communities in which they reside. As such, these youth are often faced with different cultural and immigrant stressors. Although prior research documented the detrimental impact of cultural and immigrant stressors, variable-centered approaches fail to account for the fact that these stressors often co-occur. Addressing this gap, the current study identified typologies of cultural stressors in Hispanic/Latino adolescents using latent profile analysis. Cultural stress profiles were derived using socio-political stress, language brokering, in-group identity threats, and within-group discrimination as indicators. The study was conducted in two sites (Los Angeles and Miami; total N = 306) during Spring and Summer 2020. A four-profile solution was identified: Low Cultural Stress (n = 94, 30.7%), Sociopolitical and Language Brokering Stress (n = 147, 48%), Sociopolitical and In-group Identity Threat Stress (n = 48, 15.7%), and Higher Stress (n = 17, 5.6%). Results indicate that profiles with stress were characterized by worse mental health symptoms, reporting higher means of depression, stress, and lower self-esteem, as well as by higher heritage cultural orientation compared to the low stress profile. Interventions designed to mitigate the deleterious effects of cultural stressors would benefit from adopting an individualized, tailored approach that addresses youth's stress profile membership.

Perceived Negative Political Climate Among Hispanic/Latino Adolescents Before and After the 2020 U.S. Presidential Election: Associations with Internalizing Symptoms and Substance Use.

The political climate often changes following the installment of a new president. This volatility presents opportunities for examining how elections might affect vulnerable subgroups such as Hispanic/Latino (HL) adolescents. The present study explored the perception of negative political climate among HL adolescents before and after the 2020 U.S. presidential election and its association with internalizing symptoms and substance use. We conducted the study in Los Angeles and Miami between 2020-2021, with a sample of 304 HL adolescents (Females = 60.8%), aged 15.3 years on average. Participants completed measures of negative political climate (pre- post-election) and measures of depressive symptoms, anxiety, substance misuse, and substance use intentions after the election. We used paired tests and linear mixed-effects modeling to explore changes in perceived negative climate before and after the election. Structural equation modeling was used to determine predictors of negative political climate and its associations with internalizing symptoms and substance use. Results indicated that following the election negative political climate increased significantly in Miami and among Cuban-origin adolescents but not in Los Angeles or among Mexican-origin adolescents. Pre-election perceived negative political climate was significantly predicted by gender, study site, and mother's nativity. Pre-election negative political climate predicted post-election internalizing symptoms and substance use intentions indirectly through post-election negative political climate. HL youth's perceived political climate is a complex construct that might vary across different sociopolitical contexts and populational sub-groups. Exploring variations in politically-based cultural stressors and their role as mental health and substance use risk factors is crucial to addressing HL disparities. KEY WORDS: Adolescence, Hispanic/Latino, political climate, presidential election, internalizing symptoms, substance use.

Single-reaction multi-antigen serological test for comprehensive evaluation of SARS-CoV-2 patients by flow cytometry.

Here, we describe a new, simple, highly multiplexed serological test that generates a more complete picture of seroconversion than single antigen-based assays. Flow cytometry is used to detect multiple Ig isotypes binding to four SARS-CoV-2 antigens: the Spike glycoprotein, its RBD fragment (the main target for neutralizing antibodies), the nucleocapsid protein, and the main cysteine-like protease in a single reaction. Until now, most diagnostic serological tests measured antibodies to only one antigen and in some laboratory-confirmed patients no SARS-CoV-2-specific antibodies could be detected. Our data reveal that while most patients respond against all the viral antigens tested, others show a marked bias to make antibodies against either proteins exposed on the viral particle or those released after cellular infection. With this assay, it was possible to discriminate between patients and healthy controls with 100% confidence. Analysing the response of multiple Ig isotypes to the four antigens in combination may also help to establish a correlation with the severity degree of disease. A more detailed description of the immune responses of different patients to SARS-CoV-2 virus might provide insight into the wide array of clinical presentations of COVID-19.

SARS-CoV-2 Cysteine-like Protease Antibodies Can Be Detected in Serum and Saliva of COVID-19-Seropositive Individuals.

Currently, there is a need for reliable tests that allow identification of individuals that have been infected with SARS-CoV-2 even if the infection was asymptomatic. To date, the vast majority of the serological tests for SARS-CoV-2-specific Abs are based on serum detection of Abs to either the viral spike glycoprotein (the major target for neutralizing Abs) or the viral nucleocapsid protein that is known to be highly immunogenic in other coronaviruses. Conceivably, exposure of Ags released from infected cells could stimulate Ab responses that might correlate with tissue damage and, hence, they may have some value as a prognostic indicator. We addressed whether other nonstructural viral proteins, not incorporated into the infectious viral particle, specifically the viral cysteine-like protease, might also be potent immunogens. Using ELISA tests, coating several SARS-CoV-2 proteins produced in vitro, we describe that COVID-19 patients make high titer IgG, IgM, and IgA Ab responses to the Cys-like protease from SARS-CoV-2, also known as 3CLpro or Mpro, and it can be used to identify individuals with positive serology against the coronavirus. Higher Ab titers in these assays associated with more-severe disease, and no cross-reactive Abs against prior betacoronavirus were found. Remarkably, IgG Abs specific for Mpro and other SARS-CoV-2 Ags can also be detected in saliva. In conclusion, Mpro is a potent Ag in infected patients that can be used in serological tests, and its detection in saliva could be the basis for a rapid, noninvasive test for COVID-19 seropositivity.

Associations between Local Jurisdiction Ordinances and Current Use of Cannabis Products in California Adolescents.

PURPOSE: Cannabis use among adolescents may have detrimental effects and use among this age group is increasing. It is important to understand how expansion of laws permitting cannabis sales may impact adolescent use. Much of the current research has explored how state-level policy decisions may impact adolescents' use behaviors; however, there is a gap in the understanding of how differences in local jurisdictional policies may also influence underage cannabis use.Procedures: The present study cross-sectionally assesses local variation in cannabis policies to explore the potential effects of local policy on underage use behaviors. Data were collected from (N = 1,573) adolescents representing 120 different localities across California, collected as a part of Project Cal Teens. Linear regression models were used to assess associations between local jurisdiction's allowance of retail sale of cannabis for adult-use and past 30-day use of non-medical (adult use) cannabis and perceived access to cannabis products. FINDINGS: Local policy allowing cannabis retail was associated with adolescents' significantly higher past 30-day use of cannabis (ß = 0.25 95% CI = 0.08, 0.42) and perceived access (ß = 0.60 95% CI = 0.27, 0.94). CONCLUSIONS: Results highlight the impact of local cannabis policies on adolescent cannabis use and perception. Considering the effects of cannabis use on adolescent development, this is an important public health concern because 14 states have already legalized recreational retail sales and growing numbers of local jurisdictions are allowing the retail sale of recreational cannabis.

#FlavorsSaveLives: An Analysis of Twitter Posts Opposing Flavored E-cigarette Bans.

BACKGROUND: Starting in 2019 policies restricting the availability of flavored e-cigarette products were proposed or implemented in the United States to curb vaping by youth. People took to Twitter to voice their opposition, referencing the phrase "Flavors Save Lives." This study documented the emerging themes pertaining to "Flavors Saves Lives" over a 12-month period. METHODS: The study period was from May 1, 2019, to May 1, 2020. A stratified sampling procedure supplied 2500 tweets for analysis. Posts were classified by one or more of the following themes: (1) Political Referendum; (2) Institutional Distrust; (3) Individual Rights; (4) Misinformation; (5) THC Vaping is the Real Problem; (6) Smoking Cessation; (7) Adult Use; and (8) Not a Bot. The temporal pattern of tweets over the year was examined. RESULTS: Political Referendum (76.5%) and Institutional Distrust (31.3%) were the most prominent themes, followed by Not a Bot (11.0%), Individual Rights (10.4%), Adult Use (8.0%), Smoking Cessation (6.6%), Misinformation (5.9%), and THC Vaping is the Real Problem (3.5%). Total tweet frequencies increased in September 2019 and peaked in November 2019 before returning to relatively low numbers. Political Referendum and Institutional Distrust were consistently the most prevalent themes over time. CONCLUSION: Twitter posts with the phrase "Flavors Save Lives" commonly discussed voting against political incumbents and mentioned distrust of government representatives. Findings demonstrated the possibility of near real-time Twitter monitoring of public opposition to flavor bans. These data may be valuable for designing tobacco control information campaigns in the future. IMPLICATIONS: (a) Starting in 2019 policies restricting the availability of flavored e-cigarette products were proposed or implemented in the United States to curb vaping by youth. (b) This study content analyzed Twitter posts with the phrase "Flavors Save Lives" from a 12-month period to understand opposition to flavor restrictions. (c) Twitter posts commonly discussed voting against political incumbents and mentioned distrust of government representatives. (d) Findings demonstrated the possibility of near real-time Twitter monitoring of public opposition to flavor bans, and contribute to a more comprehensive assessment of different sub-population's responses to current and proposed tobacco control information policies.