Rationale
Impulsivity has been strongly linked to addictive behaviors, but can be operationalized in a number of ways that vary considerably in overlap, suggesting multidimensionality.
Objective
This ...study tested the hypothesis that the latent structure among multiple measures of impulsivity would reflect the following three broad categories:
impulsive choice
, reflecting discounting of delayed rewards;
impulsive action
, reflecting ability to inhibit a prepotent motor response; and
impulsive personality traits
, reflecting self-reported attributions of self-regulatory capacity.
Methods
The study used a cross-sectional confirmatory factor analysis of multiple impulsivity assessments. Participants were 1252 young adults (62 % female) with low levels of addictive behavior, who were assessed in individual laboratory rooms at the University of Chicago and the University of Georgia. The battery comprised a Delay (replace hyphen with space) Discounting Task, Monetary Choice Questionnaire, Conners’ Continuous Performance Test, Go/NoGo Task, Stop Signal Task, Barratt Impulsiveness Scale, and the UPPS-P Impulsive Behavior Scale.
Results
The hypothesized three-factor model provided the best fit to the data, although sensation seeking was excluded from the final model. The three latent factors were largely unrelated to each other and were variably associated with substance use.
Conclusions
These findings support the hypothesis that diverse measures of impulsivity can broadly be organized into three categories that are largely distinct from one another. These findings warrant investigation among individuals with clinical levels of addictive behavior and may be applied to understanding the underlying biological mechanisms of these categories.
Tissue-resident immune cells span both myeloid and lymphoid cell lineages, have been found in multiple human tissues, and play integral roles at all stages of the immune response, from maintaining ...homeostasis to responding to infectious challenges to resolution of inflammation to tissue repair. In humans, studying immune cells and responses in tissues is challenging, although recent advances in sampling and high-dimensional profiling have provided new insights into the ontogeny, maintenance, and functional role of tissue-resident immune cells. Each tissue contains a specific complement of resident immune cells. Moreover, resident immune cells for each lineage share core properties, along with tissue-specific adaptations. Here we propose a five-point checklist for defining resident immune cell types in humans and describe the currently known features of resident immune cells, their mechanisms of development, and their putative functional roles within various human organs. We also consider these aspects of resident immune cells in the context of future studies and therapeutics.
Immune response dynamics in coronavirus disease 2019 (COVID-19) and their severe manifestations have largely been studied in circulation. Here, we examined the relationship between immune processes ...in the respiratory tract and circulation through longitudinal phenotypic, transcriptomic, and cytokine profiling of paired airway and blood samples from patients with severe COVID-19 relative to heathy controls. In COVID-19 airways, T cells exhibited activated, tissue-resident, and protective profiles; higher T cell frequencies correlated with survival and younger age. Myeloid cells in COVID-19 airways featured hyperinflammatory signatures, and higher frequencies of these cells correlated with mortality and older age. In COVID-19 blood, aberrant CD163+ monocytes predominated over conventional monocytes, and were found in corresponding airway samples and in damaged alveoli. High levels of myeloid chemoattractants in airways suggest recruitment of these cells through a CCL2-CCR2 chemokine axis. Our findings provide insights into immune processes driving COVID-19 lung pathology with therapeutic implications for targeting inflammation in the respiratory tract.
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•Airways show localized immune responses correlating to age and outcome in COVID-19•Airway T cells are activated and resident, while myeloid cells are hyperinflammatory•Aberrant CD163hi and HLA-DRlo monocytes predominate in COVID-19 blood•Monocytes infiltrate airways and lung alveoli potentially through a CCL2-CCR2 axis
Through longitudinal profiling of paired airways and blood from patients with severe COVID-19, Szabo et al. reveal airway immune responses that correlate with age and outcome. They further identify coordinate roles for T and myeloid cells in the respiratory tract and circulation in perpetuating lung pathology and disease pathogenesis.
An Alcohol Purchase Task (APT) is a novel behavioral economic measure for characterizing the incentive value of alcohol to an individual (i.e., alcohol demand). Individual differences in alcohol ...demand have been associated with a number of alcohol-related outcomes and the current investigation sought to extend these previous findings in a number of ways. The goals of the study were: (a) to examine the relationship between alcohol demand and alcohol misuse in a large sample of community adults; (b) to examine sex differences in alcohol demand; and, (c) to examine the relationship between alcohol demand and impulsive personality traits, both in general and as moderating variables. Participants (N = 720; 39% female) were adult smokers who reported drinking in the last year and were recruited from the community at large. All four behavioral economic indices of demand from the APT were significantly associated with alcohol misuse, with Omax and intensity uniquely associated in combined analyses. Males exhibited significantly higher demand, but these differences were largely eliminated after adjusting for drinks per week and other covariates. Trait levels of urgency, sensation-seeking and lack of premeditation were significantly associated with intensity and urgency was associated with Omax, but no moderating relationships were present. The significant relationships between aspects of impulsivity and the demand indices may signify a common process underlying disinhibition and demand for alcohol. These findings further support the relationship between indices of alcohol demand and alcohol misuse and a link between demand and impulsivity. Methodological considerations and future directions are discussed.
Impulsive personality traits are complex heritable traits that are governed by frontal-subcortical circuits and are associated with numerous neuropsychiatric disorders, particularly drug abuse and ...attention-deficit/hyperactivity disorder (ADHD). In collaboration with the genetics company 23andMe, we performed 10 genome-wide association studies on measures of impulsive personality traits the short version of the UPPS-P Impulsive Behavior Scale, and the Barratt Impulsiveness Scale (BIS-11) and drug experimentation (the number of drug classes an individual had tried in their lifetime) in up to 22,861 male and female adult human research participants of European ancestry. Impulsive personality traits and drug experimentation showed single nucleotide polymorphism heritabilities that ranged from 5 to 11%. Genetic variants in the
locus were significantly associated with UPPS-P Sensation Seeking (
= 8.3 × 10
, rs139528938) and showed a suggestive association with Drug Experimentation (
= 3.0 × 10
, rs2163971;
= 0.68 with rs139528938). Furthermore, genetic variants in the
locus were significantly associated with UPPS-P Negative Urgency (
= 3.8 × 10
; rs199694726). The role of these genes was supported by single variant, gene- and transcriptome-based analyses. Multiple subscales from both UPPS-P and BIS showed strong genetic correlations (>0.5) with Drug Experimentation and other substance use traits measured in independent cohorts, including smoking initiation, and lifetime cannabis use. Several UPPS-P and BIS subscales were genetically correlated with ADHD (
= 0.30-0.51), supporting their validity as endophenotypes. Our findings demonstrate a role for common genetic contributions to individual differences in impulsivity. Furthermore, our study is the first to provide a genetic dissection of the relationship between different types of impulsive personality traits and various psychiatric disorders.
Impulsive personality traits (IPTs) are heritable traits that are governed by frontal-subcortical circuits and are associated with neuropsychiatric disorders, particularly substance use disorders. We have performed genome-wide association studies of IPTs to identify regions and genes that account for this heritable variation. IPTs and drug experimentation were modestly heritable (5-11%). We identified an association between single nucleotide polymorphisms in
and both sensation seeking and drug experimentation; and between variants in
and negative urgency. The role of these genes was supported by single variant, gene- and transcriptome-based analyses. This study provides evidence that impulsivity can be genetically separated into distinct components. We showed that IPT are genetically associated with substance use and ADHD, suggesting impulsivity is an endophenotype contributing to these psychiatric conditions.
Previous research has implicated demographic, psychological, behavioral, and cognitive variables in the onset and maintenance of pediatric overweight/obesity. No adequately-powered study has ...simultaneously modeled these variables to assess their relative associations with body mass index (BMI; kg/m2) in a nationally representative sample of youth.
Multiple machine learning regression approaches were employed to estimate the relative importance of 43 demographic, psychological, behavioral, and cognitive variables previously associated with BMI in youth to elucidate the associations of both fixed (e.g. demographics) and potentially modifiable (e.g. psychological/behavioral) variables with BMI in a diverse representative sample of youth. The primary analyses consisted of 9-10 year olds divided into a training (n = 2724) and test (n = 1123) sets. Secondary analyses were conducted by sex, ethnicity, and race.
The full sample model captured 12% of the variance in both the training and test sets, suggesting good generalizability. Stimulant medications and demographic factors were most strongly associated with BMI. Lower attention problems and matrix reasoning (i.e. nonverbal abstract problem solving and inductive reasoning) and higher social problems and screen time were robust positive correlates in the primary analyses and in analyses separated by sex.
Beyond demographics and stimulant use, this study highlights abstract reasoning as an important cognitive variable and reaffirms social problems and screen time as significant correlates of BMI and as modifiable therapeutic targets. Prospective data are needed to understand the predictive power of these variables for BMI gain.
A distinct CD83-expressing subset of γδ T cells are enriched in preterm infants with sepsis, providing insights into their functional maturation dynamics in settings of homeostasis and disease ...(León-Lara et al. https://doi.org/10.1084/jem.20231987).
The gender gap in physician pay is often attributed in part to women working fewer hours than men, but evidence to date is limited by self-report and a lack of detail regarding clinical revenue and ...gender differences in practice style.
Using national all-payer claims and data from electronic health records, we conducted a cross-sectional analysis of 24.4 million primary care office visits in 2017 and performed comparisons between female and male physicians in the same practices. Our primary independent variable was physician gender; outcomes included visit revenue, visit counts, days worked, and observed visit time (interval between the initiation and the termination of a visit). We created multivariable regression models at the year, day, and visit level after adjustment for characteristics of the primary care physicians (PCPs), patients, and types of visit and for practice fixed effects.
In 2017, female PCPs generated 10.9% less revenue from office visits than their male counterparts (-$39,143.2; 95% confidence interval CI, -53,523.0 to -24,763.4) and conducted 10.8% fewer visits (-330.5 visits; 95% CI, -406.6 to -254.3) over 2.6% fewer clinical days (-5.3 days; 95% CI, -7.7 to -3.0), after adjustment for age, academic degree, specialty, and number of sessions worked per week, yet spent 2.6% more observed time in visits that year than their male counterparts (1201.3 minutes; 95% CI, 184.7 to 2218.0). Per visit, after adjustment for PCP, patient, and visit characteristics, female PCPs generated equal revenue but spent 15.7% more time with a patient (2.4 minutes; 95% CI, 2.1 to 2.6). These results were consistent in subgroup analyses according to the gender and health status of the patients and the type and complexity of the visits.
Female PCPs generated less visit revenue than male colleagues in the same practices owing to a lower volume of visits, yet spent more time in direct patient care per visit, per day, and per year. (Funded in part by the Robert Wood Johnson Foundation.).
This work presents a method for using nanosecond repetitively pulsed (NRP) plasma discharges for accelerating a propagating flame such that the deflagration-to-detonation transition occurs. A ...strategy is developed for bringing the location of the plasma near the tube wall and, thus, reducing the presence of the electrodes in the combustion tube as well as presenting a configuration in which cooling of the electrodes is viable for practical applications. Time-of-flight measurements were used in combination with energy deposition measurements and high-speed OH*-chemiluminescence imagery to investigate the flame acceleration process. For stoichiometric hydrogen–air flames, successful transition to detonation was achieved by applying a burst of 110 pulses at 100 kHz, with energies as low as 10 mJ per pulse. This was also achieved when plasma discharges were applied in the vicinity of the wall. Two enhancement mechanisms for flame acceleration were identified. The essential role of shock–flame interaction was established as being the main mechanism for flame acceleration when the discharges are located near the wall. This work presents an effective alternative that allows for NRP discharges to be applied near the wall while successfully maintaining a promising success rate for detonation transition.
This work provides proof of concept for the use of nanosecond repetitively pulsed (NRP) plasma discharges to accelerate a propagating turbulent flame, resulting in enhanced deflagration-to-detonation ...transition and significant reduction in run-up length. The investigations are conducted on a stoichiometric hydrogen-air mixture at near ambient conditions. The effect of plasma actuation on the flame velocity is investigated using time-of-flight measurements of the propagating flame and detonation wave. The flame velocity shortly after the application of the NRP plasma discharges is more than double that obtained in cases in which no plasma is applied. High-speed imaging of OH* chemiluminescence in the electrode area confirms this result and provides insight about the mechanisms of plasma action. While the volumetric energy deposited during plasma actuation is sufficiently low as to not ignite the combustible mixture prior the arrival of the flame, the chemical and thermal enhancement of the gas is efficient enough to significantly accelerate the transition to detonation. The decrease in the run-up length to transition to detonation is obtained for a plasma power of less than 0.14% of the thermal power of the flame. This result indicates that low-energy active devices using NRP discharges might be suitable for replacing passive devices such as orifice plates or Shchelkin spirals.
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