Abnormally High Graphitic Crystallization of Cellulose Nanocrystals.

Cellulose nanocrystals (CNCs) are currently of great interest for many applications, such as energy storage and nanocomposites, because of their natural abundance. A number of carbonization studies have reported abnormal graphitization behavior of CNCs, although cellulose is generally known as a precursor for hard carbon (nongraphitizable carbon). Herein, we report a spray-freeze-drying (SFD) method for CNCs and a subsequent carbonization study to ascertain the difference in the structural development between the amorphous and crystalline phases. The morphological observation by high-resolution transmission electron microscopy of the carbonized SFD-CNC clearly shows that the amorphous and crystalline phases of CNC are attributed to the formation of hard and soft carbon, respectively. The results of a reactive molecular dynamics (RMD) study also show that the amorphous cellulose phase leads to the formation of fewer carbon ring structures, indicative of hard carbon. In contrast, the pristine crystalline cellulose phase has a higher density and thermal stability, resulting in limited molecular relaxation and the formation of a highly crystalline graphitic structure (soft carbon).

Scalable Design of Ru-Embedded Carbon Fabric Using Conventional Carbon Fiber Processing for Robust Electrocatalysts.

Metal-carbon composites are extensively utilized as electrochemical catalysts but face critical challenges in mass production and stability. We report a scalable manufacturing process for ruthenium surface-embedded fabric electrocatalysts (Ru-SFECs) via conventional fiber/fabric manufacturing. Ru-SFECs have excellent catalytic activity and stability toward the hydrogen evolution reaction, exhibiting a low overpotential of 11.9 mV at a current density of 10 mA cm-2 in an alkaline solution (1.0 M aq KOH solution) with only a slight overpotential increment (6.5%) after 10,000 cycles, whereas under identical conditions, that of commercial Pt/C increases 6-fold (from 1.3 to 7.8 mV). Using semipilot-scale equipment, a protocol is optimized for fabricating continuous self-supported electrocatalytic electrodes. Tailoring the fiber processing parameters (tension and temperature) can optimize the structural development, thereby achieving good catalytic performance and mechanical integrity. These findings underscore the significance of self-supporting catalysts, offering a general framework for stable, binder-free electrocatalytic electrode design.

NJK14047 inhibition of p38 MAPK ameliorates inflammatory immune diseases by suppressing T cell differentiation.

p38 MAPK has been implicated in the pathogenesis of rheumatoid arthritis and psoriasis. To assess the therapeutic efficacy of the p38 MAPK inhibitor NJK14047 in the treatment of rheumatoid arthritis and psoriasis, we developed mouse models of collagen-induced rheumatoid arthritis (CIA) and imiquimod-induced psoriasis (IIP). NJK14047 was found to suppress arthritis development and psoriasis symptoms and also suppressed histopathological changes induced by CIA and IIP. Furthermore, we established that CIA and IIP evoked increases in the mRNA expression levels of Th1/Th17 inflammatory cytokines in the joints and skin, which was again suppressed by NJK14047. NJK14047 reversed the enlargement of spleens induced by CIA and IIP as well as increases in the levels of inflammatory cytokine in spleens following induction by CIA and IIP. In human SW982 synovial cells, NJK14047 was found to suppress lipopolysaccharide-induced increases in the mRNA expression of proinflammatory cytokines. NJK14047 inhibition of p38 MAPK suppressed the differentiation of naïve T cells to Th17 and Th1 cells. Our findings in this study provide convincing evidence indicating the therapeutic efficacy of the p38 MAPK inhibitor NJK14047 against CIA and IIP, which we speculate could be associated with the suppression on T-cell differentiation.

COVID-19 and Mortality in the Global Surgical Population: A Systematic Review and Meta-Analysis.

INTRODUCTION: To date, no systematic review or meta-analysis has comprehensively estimated the risk of mortality by surgery type on an international scale. We aim to delineate the risk of mortality in patients with COVID-19 who undergo surgery. METHODS: PubMed (MEDLINE), Scopus, OVID, the World Health Organization Global Literature on Coronavirus Disease, and Corona-Central databases were searched from December 2019 through January 2022. Studies providing data on mortality in patients undergoing surgery were included. The Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines for abstracting data were followed and performed independently by two reviewers. The main outcome was mortality in patients with COVID-19. RESULTS: Of a total of 4023 studies identified, 46 studies with 80,015 patients met our inclusion criteria. The mean age was 67 y; 57% were male. Surgery types included general (14.9%), orthopedic (23.4%), vascular (6.4%), thoracic (10.6%), and urologic (8.5%). Patients undergoing surgery with COVID-19 elicited a nine-fold increased risk of mortality (relative risk [RR] 8.99, 95% confidence interval [CI] 4.96-16.32) over those without COVID-19. In low-income and middle-income countries (RR: 16.04, 95% CI: 4.59-56.12), the mortality risk was twice as high compared to high-income countries (RR: 7.50, 95% CI: 4.30-13.09). CONCLUSIONS: Mortality risk in surgical patients with COVID-19 compared to those without is increased almost 10-fold. The risk was highest in low-income and middle-income countries compared to high-income countries, suggesting a disproportionate effect of the pandemic on resource-constrained regions.

Water Quality Monitoring with the Multiplexed Assay MitoOxTox for Mitochondrial Toxicity, Oxidative Stress Response, and Cytotoxicity in AREc32 Cells.

Mitochondria play a key role in the energy production of cells, but their function can be disturbed by environmental toxicants. We developed a cell-based mitochondrial toxicity assay for environmental chemicals and their mixtures extracted from water samples. The reporter gene cell line AREc32, which is frequently used to quantify the cytotoxicity and oxidative stress response of water samples, was multiplexed with an endpoint of mitochondrial toxicity. The disruption of the mitochondrial membrane potential (MMP) was quantified by high-content imaging and compared to measured cytotoxicity, predicted baseline toxicity, and activation of the oxidative stress response. Mitochondrial complex I inhibitors showed highly specific effects on the MMP, with minor effects on cell viability. Uncouplers showed a wide distribution of specificity on the MMP, often accompanied by specific cytotoxicity (enhanced over baseline toxicity). Mitochondrial toxicity and the oxidative stress response were not directly associated. The multiplexed assay was applied to water samples ranging from wastewater treatment plant (WWTP) influent and effluent and surface water to drinking and bottled water from various European countries. Specific effects on MMP were observed for the WWTP influent and effluent. This new MitoOxTox assay is an important complement for existing in vitro test batteries for water quality testing and has potential for applications in human biomonitoring.

Multimodal Haptic Feedback for Virtual Collisions Combining Vibrotactile and Electrical Muscle Stimulation.

In this paper, we explore the effects of multimodal haptic feedback combining vibrotactile and electrical muscle stimulation (EMS) on expressing virtual collisions. We first present a wearable multimodal haptic device capable of generating both mechanical vibration and EMS stimuli. The two types of haptic stimulus are combined into a haptic rendering method that conveys improved virtual collision sensations. This multimodal rendering method highlights the strengths of each modality while compensating for mutual weaknesses. The multimodal rendering method is compared in subjective quality with two unimodal methods (vibration only and EMS only) by a user study. Experimental results demonstrate that our multimodal feedback method can elicit more realistic, enjoyable, expressive, and preferable user experiences.

Life under the snow: A year-round transcriptome analysis of Antarctic mosses in natural habitats provides insight into the molecular adaptation of plants under extreme environment.

Mosses are vital components of ecosystems, exhibiting remarkable adaptability across diverse habitats from deserts to polar ice caps. Sanionia uncinata (Hedw.) Loeske, a dominant Antarctic moss survives extreme environmental condition through perennial lifecycles involving growth and dormancy alternation. This study explores genetic controls and molecular mechanisms enabling S. uncinata to cope with seasonality of the Antarctic environment. We analysed the seasonal transcriptome dynamics of S. uncinata collected monthly from February 2015 to January 2016 in King George Island, Antarctica. Findings indicate that genes involved in plant growth were predominantly upregulated in Antarctic summer, while those associated with protein synthesis and cell cycle showed marked expression during the winter-to-summer transition. Genes implicated in cellular stress and abscisic acid signalling were highly expressed in winter. Further, validation included a comparison of the Antarctic field transcriptome data with controlled environment simulation of Antarctic summer and winter temperatures, which revealed consistent gene expression patterns in both datasets. This proposes a seasonal gene regulatory model of S. uncinate to understand moss adaptation to extreme environments. Additionally, this data set is a valuable resource for predicting genetic responses to climatic fluctuations, enhancing our knowledge of Antarctic flora's resilience to global climate change.

In vitro bioassays for monitoring drinking water quality of tap water, domestic filtration and bottled water.

BACKGROUND: Location-specific patterns of regulated and non-regulated disinfection byproducts (DBPs) were detected in tap water samples of the Barcelona Metropolitan Area. However, it remains unclear if the detected DBPs together with undetected DPBs and organic micropollutants can lead to mixture effects in drinking water. OBJECTIVE: To evaluate the neurotoxicity, oxidative stress response and cytotoxicity of 42 tap water samples, 6 treated with activated carbon filters, 5 with reverse osmosis and 9 bottled waters. To compare the measured effects of the extracts with the mixture effects predicted from the detected concentrations and the relative effect potencies of the detected DBPs using the mixture model of concentration addition. METHODS: Mixtures of organic chemicals in water samples were enriched by solid phase extraction and tested for cytotoxicity and neurite outgrowth inhibition in the neuronal cell line SH-SY5Y and for cytotoxicity and oxidative stress response in the AREc32 assay. RESULTS: Unenriched water did not trigger neurotoxicity or cytotoxicity. After up to 500-fold enrichment, few extracts showed cytotoxicity. Disinfected water showed low neurotoxicity at 20- to 300-fold enrichment and oxidative stress response at 8- to 140-fold enrichment. Non-regulated non-volatile DBPs, particularly (brominated) haloacetonitriles dominated the predicted mixture effects of the detected chemicals and predicted effects agreed with the measured effects. By hierarchical clustering we identified strong geographical patterns in the types of DPBs and their association with effects. Activated carbon filters did not show a consistent reduction of effects but domestic reverse osmosis filters decreased the effect to that of bottled water. IMPACT STATEMENT: Bioassays are an important complement to chemical analysis of disinfection by-products (DBPs) in drinking water. Comparison of the measured oxidative stress response and mixture effects predicted from the detected chemicals and their relative effect potencies allowed the identification of the forcing agents for the mixture effects, which differed by location but were mainly non-regulated DBPs. This study demonstrates the relevance of non-regulated DBPs from a toxicological perspective. In vitro bioassays, in particular reporter gene assays for oxidative stress response that integrate different reactive toxicity pathways including genotoxicity, may therefore serve as sum parameters for drinking water quality assessment.

Sound-to-Touch Crossmodal Pitch Matching for Short Sounds.

This article explores how to relate sound and touch in terms of their spectral characteristics based on crossmodal congruence. The context is the audio-to-tactile conversion of short sounds frequently used for user experience improvement across various applications. For each short sound, a single-frequency amplitude-modulated vibration is synthesized so that their intensive and temporal characteristics are very similar. It leaves the vibration frequency, which determines the tactile pitch, as the only variable. Each sound is paired with many vibrations of different frequencies. The congruence between sound and vibration is evaluated for 175 pairs (25 sounds × 7 vibration frequencies). This dataset is employed to estimate a functional relationship from the sound loudness spectrum of sound to the most harmonious vibration frequency. Finally, this sound-to-touch crossmodal pitch mapping function is evaluated using cross-validation. To our knowledge, this is the first attempt to find general rules for spectral matching between sound and touch.

Genome-Wide Identification and Comprehensive Analysis of the GASA Gene Family in Peanuts (Arachis hypogaea L.) under Abiotic Stress.

Peanut (Arachis hypogaea L.) is a globally cultivated crop of significant economic and nutritional importance. The role of gibberellic-acid-stimulated Arabidopsis (GASA) family genes is well established in plant growth, development, and biotic and abiotic stress responses. However, there is a gap in understanding the function of GASA proteins in cultivated peanuts, particularly in response to abiotic stresses such as drought and salinity. Thus, we conducted comprehensive in silico analyses to identify and verify the existence of 40 GASA genes (termed AhGASA) in cultivated peanuts. Subsequently, we conducted biological experiments and performed expression analyses of selected AhGASA genes to elucidate their potential regulatory roles in response to drought and salinity. Phylogenetic analysis revealed that AhGASA genes could be categorized into four distinct subfamilies. Under normal growth conditions, selected AhGASA genes exhibited varying expressions in young peanut seedling leaves, stems, and roots tissues. Notably, our findings indicate that certain AhGASA genes were downregulated under drought stress but upregulated under salt stress. These results suggest that specific AhGASA genes are involved in the regulation of salt or drought stress. Further functional characterization of the upregulated genes under both drought and salt stress will be essential to confirm their regulatory roles in this context. Overall, our findings provide compelling evidence of the involvement of AhGASA genes in the mechanisms of stress tolerance in cultivated peanuts. This study enhances our understanding of the functions of AhGASA genes in response to abiotic stress and lays the groundwork for future investigations into the molecular characterization of AhGASA genes.

Qualitative Assessment of a Human Trafficking Module Intervention in Pharmacy Education.

Description of the Problem: Human trafficking is a critical public health threat in the United States, yet education on human trafficking for pharmacy students has not been evaluated despite pharmacists being the most accessible health care professionals. Description of the Innovation: To evaluate the most valuable aspects of an introductory module on human trafficking, pharmacy students participated in a human trafficking module, and their perception of human trafficking was evaluated after the module. Content on human trafficking was delivered through an asynchronous online presentation followed by a synchronous Zoom class discussion. Fifty-three third-year pharmacy students from the Women's Health elective in the fall semester of 2020 at the University of Minnesota - College of Pharmacy were included. Consensual Qualitative Research methodology was used for qualitative data analysis. Critical Analysis: Students' perceptions of the value of this learning module was evaluated through consensual qualitative research. The findings suggest the module held significant value for students to better understand human trafficking and the role of pharmacists. Implications: A hybrid model on human trafficking involving discussions, case examples, and questions posed by students was found to have a positive impact on their knowledge on human trafficking. The results of this study will provide direction for future modules, classes, or adaptations to the curriculum on human trafficking for pharmacy students and may prove beneficial for other health care professionals.

Twenty years of research on shrinking cities: a focus on keywords and authors.

Most scholarly attention to vanishing cities is fairly recent so, to guide future research, a comprehensive evaluation of prior findings is required. This study is a network analysis of 333 publications authored in English, published over the last two decades. The findings are as follows: (1) shrinking city research has increased significantly since 2016; (2) the key themes are planning, decline, depopulation, policy, regeneration, vacant land, green infrastructure, and case studies such as Detroit; and (3) major academic groups have not yet collaborated effectively on the subject.

Human Pancreatic α-Cell Heterogeneity and Trajectory Inference Analysis Using Integrated Single Cell- and Single Nucleus-RNA Sequencing Platforms.

Prior studies have shown that pancreatic α-cells can transdifferentiate into ß-cells, and that ß-cells de-differentiate and are prone to acquire an α-cell phenotype in type 2 diabetes (T2D). However, the specific human α-cell and ß-cell subtypes that are involved in α-to-ß-cell and ß-to-α-cell transitions are unknown. Here, we have integrated single cell RNA sequencing (scRNA-seq) and single nucleus RNA-seq (snRNA-seq) of isolated human islets and human islet grafts and provide additional insight into α-ß cell fate switching. Using this approach, we make seven novel observations. 1) There are five different GCG -expressing human α-cell subclusters [α1, α2, α-ß-transition 1 (AB-Tr1), α-ß-transition 2 (AB-Tr2), and α-ß (AB) cluster] with different transcriptome profiles in human islets from non-diabetic donors. 2) The AB subcluster displays multihormonal gene expression, inferred mostly from snRNA-seq data suggesting identification by pre-mRNA expression. 3) The α1, α2, AB-Tr1, and AB-Tr2 subclusters are enriched in genes specific for α-cell function while AB cells are enriched in genes related to pancreatic progenitor and ß-cell pathways; 4) Trajectory inference analysis of extracted α- and ß-cell clusters and RNA velocity/PAGA analysis suggests a bifurcate transition potential for AB towards both α- and ß-cells. 5) Gene commonality analysis identifies ZNF385D, TRPM3, CASR, MEG3 and HDAC9 as signature for trajectories moving towards ß-cells and SMOC1, PLCE1, PAPPA2, ZNF331, ALDH1A1, SLC30A8, BTG2, TM4SF4, NR4A1 and PSCK2 as signature for trajectories moving towards α-cells. 6) Remarkably, in contrast to the events in vitro , the AB subcluster is not identified in vivo in human islet grafts and trajectory inference analysis suggests only unidirectional transition from α-to-ß-cells in vivo . 7) Analysis of scRNA-seq datasets from adult human T2D donor islets reveals a clear unidirectional transition from ß-to-α-cells compatible with dedifferentiation or conversion into α-cells. Collectively, these studies show that snRNA-seq and scRNA-seq can be leveraged to identify transitions in the transcriptional status among human islet endocrine cell subpopulations in vitro , in vivo , in non-diabetes and in T2D. They reveal the potential gene signatures for common trajectories involved in interconversion between α- and ß-cells and highlight the utility and power of studying single nuclear transcriptomes of human islets in vivo . Most importantly, they illustrate the importance of studying human islets in their natural in vivo setting.

Discovery of 3-Phenyl Indazole-Based Novel Chemokine-like Receptor 1 Antagonists for the Treatment of Psoriasis.

Chemokine-like receptor 1 (CMKLR1)─a G protein-coupled receptor─has functional roles in the immune system and related diseases, including psoriasis and metabolic diseases. Psoriasis is a chronic inflammatory disease characterized by skin redness, scaliness, and itching. In this study, we sought to develop novel CMKLR1 antagonists by screening our in-house GPCR-targeting compound library. Moreover, we optimized a phenylindazole-based hit compound with antagonistic activities and evaluated its oral pharmacokinetic properties in a murine model. A structure-based design on the human CMKLR1 homology model identified S-26d as an optimized compound that serves as a potent and orally available antagonist with a pIC50 value of 7.44 in hCMKLR1-transfected CHO cells. Furthermore, in the imiquimod-induced psoriasis-like mouse model, oral administration of S-26d for 1 week significantly alleviated modified psoriasis area and severity index scores (severity of erythema, scaliness, skin thickness) compared with the control group.

Intergenerational Continuity of Childhood Adversity and Its Underlying Mechanisms Among Teen Mothers and Their Offspring.

The present study investigates how parenting stress mediates the intergenerational continuity of childhood adversity in teenage mothers. Childhood adversity experiences of caregivers significantly affect their offspring's exposure to childhood adversity. However, little is known about the mechanisms linking childhood adversity across generations. The study measures how parental distress and parent-child dysfunctional interaction mediate the association between teen mothers' childhood adversity and their offspring's adversity, measuring when the offspring reached 11.5 years of age. The results revealed that parental distress, but not parent-child dysfunctional interaction, mediated the association between teen mothers' child abuse and their offspring's household dysfunction. This suggests that parental distress may be a crucial intervention target to prevent the intergenerational continuity of childhood adversity. The findings imply that efforts to prevent the intergenerational continuity of childhood adversity may be more successful if the public and professionals have a broader understanding of the associations between early adversity and parenting contexts. In conclusion, the study shed light on the potential mechanisms underlying the intergenerational continuity of childhood adversity and highlights the importance of targeting parenting stress, specifically parental distress, as an intervention strategy to prevent the perpetuation of childhood adversity across generations.

The development and evaluation of a self-efficacy enhancement program for older adults with mild cognitive impairment.

OBJECTIVE: The aims of this study were to develop a self-efficacy enhancement program and to evaluate its effect on cognitive function, dementia knowledge, self-efficacy, depression, and dementia preventive behaviors in older adults (age ≥ 65 years) with mild cognitive impairment (MCI). METHODS: This equivalent control group pretest-posttest study was conducted at a tertiary hospital in Seoul, South Korea. Older adults with MCI were randomly allocated to an experimental (EG, n = 16) or control group (CG, n = 16). The EG underwent an 8-week intervention (weekly 60-min session) utilizing self-efficacy enhancement strategies; the CG received usual care. The intervention was comprised of physical, cognitive, and emotional activities and was followed by 4-week maintenance during which both groups engaged in self-learning at home with a dementia preventive guidebook. Outcome data were evaluated at the pretest and 8, 10, and 12 weeks later. This study adhered to the CONSORT guidelines. RESULTS: There were significant differences in cognitive function, dementia knowledge, self-efficacy, and dementia preventive behaviors, but not in depression between the two groups over the time. Regarding cognitive function subdomains, significant differences were observed in visuospatial/executive, attention, language, and delayed recall. CONCLUSION: The integrated intervention consisting of physical, cognitive, and emotional activities was effective in improving cognitive function, dementia knowledge, self-efficacy, and dementia preventive behaviors. This suggests that this program can be utilized as an educational program to prevent dementia in older adults with MCI in dementia support centers, public health centers, clinics, and hospitals. TRIAL REGISTRATION: KCT0006094 in the Clinical Research Information Service. Retrospectively registered 23 April 2021, https://cris.nih.go.kr/cris/search/listDetail.do.

Maternal childhood adversity and adolescent marijuana use at age 17 years: The role of parental mental health and parenting behaviors.

INTRODUCTION: Children's risk for marijuana use may be linked to their parents' history of childhood adversity, yet little is known about the mechanisms underlying this link. This study examined whether maternal parenting behavior and mental health serve as mechanisms linking maternal childhood adversity to their children's marijuana use at age 17 years, by gender. METHODS: Data were from the Young Women and Child Development Study (59% male), a longitudinal panel study, which began in 1988 and followed mother-child dyads for 17 years (n = 240). Participants were recruited from health and social services agencies located in a metropolitan region of Washington State. Hypotheses were tested using Structural Equation Modeling in Mplus. Multiple-group analysis was conducted to evaluate potential gender differences. RESULTS: Results showed that maternal childhood adversity was associated with their mental health outcomes (ß = .32, p < .001), which in turn was predictive of mothers' harsh parenting (ß = .27, p < .01). Maternal harsh parenting behavior was then associated with their children's marijuana use at age 17 years (ß = .34, p < .001). Multiple group analyses revealed that the path from harsh parenting to adolescent marijuana use differed across genders being only significant for boys (ß = .42, p < .001). CONCLUSIONS: The intergenerational impact of childhood adversity highlights the need for interventions that target both parents and children. This would support teen mothers with a history of childhood adversity to acquire skills and knowledge to help mitigate its impact on their parenting behaviors and offset risks for their children.

Enhancing Hydrophilicity of Thick Electrodes for High Energy Density Aqueous Batteries.

Thick electrodes can substantially enhance the overall energy density of batteries. However, insufficient wettability of aqueous electrolytes toward electrodes with conventional hydrophobic binders severely limits utilization of active materials with increasing the thickness of electrodes for aqueous batteries, resulting in battery performance deterioration with a reduced capacity. Here, we demonstrate that controlling the hydrophilicity of the thicker electrodes is critical to enhancing the overall energy density of batteries. Hydrophilic binders are synthesized via a simple sulfonation process of conventional polyvinylidene fluoride binders, considering physicochemical properties such as mechanical properties and adhesion. The introduction of abundant sulfonate groups of binders (i) allows fast and sufficient electrolyte wetting, and (ii) improves ionic conduction in thick electrodes, enabling a significant increase in reversible capacities under various current densities. Further, the sulfonated binder effectively inhibits the dissolution of cathode materials in reactive aqueous electrolytes. Overall, our findings significantly enhance the energy density and contribute to the development of practical zinc-ion batteries.

A Qualitative Study on the Self-Care Experiences of People with Heart Failure.

We aimed to explore in-depth experiences and emotions of people with heart failure within the context of self-care. A qualitative descriptive study was conducted using semi-structured interviews. Ten patients were recruited from an outpatient clinic at a university-affiliated hospital in South Korea between September and November 2019. Data were analyzed using a thematic content analysis approach. Participants were 68-86 years old, and 80% were men. Five themes of the self-care experiences of persons with heart failure were identified: "Suddenly diagnosed with heart failure," "Unpredictable symptoms and unprepared for self-care," "Dependent on caring family on a heartbreaking uphill," "Self-care efforts with apprehension," and "Continued self-care efforts with expert help." Programs to support self-care for people with heart failure are needed and should be developed by incorporating patients' needs and reflecting their uncertainty and vulnerability.

Regular Cannabis Use During the First Year of the Pandemic: Studying Trajectories Rather Than Prevalence.

INTRODUCTION: Cannabis use in the U.S. rose early in the COVID-19 pandemic, but it is unclear whether that rise was temporary or permanent. This study estimated the nature and sociodemographic correlates of U.S. adult subpopulations regularly using cannabis by examining weekly trajectories of use during the first year of the pandemic. METHODS: Data came from the Understanding America Study, a nationally representative panel of U.S. adults (N=8,397; March 10, 2020-March 29, 2021). A growth mixture model was deployed to identify subgroups with similar regular cannabis use. Sociodemographic correlates of subgroups were examined using multinomial logistic regression. RESULTS: Four cannabis-use groups were identified. Most participants did not regularly use cannabis (no regular use; 81.7%). The other groups increased regular use until April 2020 but then diverged. Some (7.1%) decreased thereafter, whereas others (3.4%) maintained their elevated use until October 26, 2020 before decreasing. The last group (7.7%) sustained their elevated use throughout. Individuals aged between 18 and 39 years, unmarried, living in poverty, without a college degree, and with longer unemployment or underemployment spells had higher odds of being in the other groups with more weekly use than in the no-regular-use group. CONCLUSIONS: The analyses revealed population subgroups with prolonged regular cannabis use and a disproportionate concentration of socioeconomically vulnerable members of society in these subgroups. These findings elucidate important heterogeneity in the subpopulations using cannabis, highlighting the urgent need to tailor public health programs for subgroups that may have unique service needs.