A strong astrophysical constraint on the violation of special relativity by quantum gravity

Special relativity asserts that physical phenomena appear the same to all unaccelerated observers. This is called Lorentz symmetry and relates long wavelengths to short ones: if the symmetry is exact it implies that space-time must look the same at all length scales. Several approaches to quantum gravity, however, suggest that there may be a microscopic structure of space-time that leads to a violation of Lorentz symmetry. This might arise because of the discreteness or non-commutivity of space-time, or through the action of extra dimensions. Here we determine a very strong constraint on a type of Lorentz violation that produces a maximum electron speed less than the speed of light. We use the observation of 100-MeV synchrotron radiation from the Crab nebula to improve the previous limit by a factor of 40 million, ruling out this type of Lorentz violation, and thereby providing an important constraint on theories of quantum gravity.

Predictors of fear of falling in dizzy and nondizzy elderly

Fear of falling may constitute an independent risk factor for disability, leading older people to unnecessarily restrict their activity. Sixty older adults with chronic dizziness and 66 healthy controls were studied to help clarify the interrelationships among demographic factors, psychological status, physical health, and fear of falling. Chronic dizziness was strongly associated with fear of falling; among dizzy patients, nearly half (47%) expressed fear of falling, in comparison with 3% of controls. In participants with dizziness, 3 factors predicted fear of falling: an activity of daily living score, the revised Symptom Checklist 90 Depression (Derogatis, 1983) score, and stability when standing with feet together. These results support the concept that fear of falling is multiply determined and that psychological factors play a major role in influencing the symptoms and responses in many older patients with dizziness.

Anorexia nervosa associated with hypothalamic tumour

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Acrocyanosis in anorexia nervosa

Acrocyanosis, an uncommon disorder of the peripheral circulation, may occur in patients with anorexia nervosa. It is not known why this should be, nor whether acrocyanosis correlates with any other features of the disorder. The findings in an unselected series of 155 anorectics are reported. Acrocyanosis occurred in 32 and was more prevalent among the more severely ill. It was associated also with pallor of the face and trunk, slower pulse rates and higher fasting plasma glucose levels. Acrocyanosis could represent a more extreme form of a heat conserving mechanism not uncommon in anorectics. The possible relationship between peripheral vascular changes and plasma glucose levels requires further study.

Plasma melatonin levels in anorexia nervosa

Plasma melatonin levels were measured at three-hourly intervals over 24 hours in 11 women with untreated anorexia nervosa, and in nine healthy women of normal weight. The circadian rhythm was unaltered but the nocturnal secretion of melatonin was significantly greater in anorectics. It is possible that this was related to nocturnal hypoglycaemia.

Exclusive, Dual, and Polytobacco Use Among US Adults by Sociodemographic Factors: Results From 3 Nationally Representative Surveys

PURPOSE

To provide tobacco product use patterns for US adults by sociodemographic group.

DESIGN

A secondary analysis of Tobacco Use Supplement to the Current Population Survey (2014-15), National Health Interview Survey (2015), and Population Assessment of Tobacco and Health (2015-16).

SETTING

United States.

SAMPLE

Three nationally representative samples of adults (N = 28,070-155,067).

MEASURES

All possible combinations of cigarette, Electronic Nicotine Delivery Systems (ENDS), other combustible product, and smokeless tobacco use, defined as current use every day or some days.

ANALYSIS

Weighted population prevalence and proportion among tobacco users of exclusive, dual, and polyuse patterns by sex, race/ethnicity, education, income, and age.

RESULTS

Exclusive cigarette use was the most prevalent pattern (10.9-12.8% of US population). Dual and polyuse were less prevalent at the population level (2.6-5.2% and 0.3-1.3%, respectively) but represented 16.7-25.5% of product use among tobacco users. Cigarette plus ENDS use was similar by sex, but men were more likely to be dual users of cigarettes plus other combustibles or smokeless tobacco. Among race/ethnic subgroups, non-Hispanic (NH) Whites were most likely to use cigarettes plus ENDS, while NH Blacks were most likely to use cigarettes plus other combustibles. Dual and polyuse were generally less common among adults with higher education, income, and age.

CONCLUSION

Differences in product use patterns by sociodemographic group likely represent different risk profiles with important implications for resulting health disparities.

Leptospirosis presenting with profuse haemoptysis

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Trends in Exclusive, Dual and Polytobacco Use among U.S. Adults, 2014-2019: Results from Two Nationally Representative Surveys

Although increases in the variety of tobacco products available to consumers have led to investigations of dual/polytobacco use patterns, few studies have documented trends in these patterns over time. We used data from the 2014/2015 and 2018/2019 Tobacco Use Supplement to the Current Population Survey (TUS-CPS) and the 2015–2019 National Health Interview Survey (NHIS) to estimate trends in the following use patterns: exclusive use of cigarettes, electronic nicotine delivery systems (ENDS), other combustibles (cigars/cigarillos/little filtered cigars and traditional pipes/hookah), and smokeless tobacco (four categories); dual use (two product groups) of each product group with cigarettes (three categories); polyuse with cigarettes (all four product groups; one category); and dual/polyuse without cigarettes (one category). We estimated trends in product use patterns overall and by age, sex, and race/ethnicity using two-sample tests for differences in linear proportions. From 2014/2015 to 2018/2019, exclusive ENDS use increased, whereas cigarettes and ENDS dual use decreased. Furthermore, polyuse with cigarettes decreased, whereas dual/polyuse without cigarettes increased, with trends varying by age, sex, and race/ethnicity. Our findings suggest that patterns of dual/polyuse with and without cigarettes have changed in recent years, indicating the need for further surveillance of concurrent tobacco product use patterns.

Anorexia nervosa: some observations on "dieters" and "vomiters", cholesterol and carotene

Twenty consecutive cases of anorexia nervosa admitted to a general medical ward were found to consist of ten who reduced weight by means of dieting and ten who in addition employed self-induced vomiting. Clinical and biochemical differences between "dieters' and "vomiters' were less pronounced than those reported elsewhere. However, the "vomiters' had higher scores on the anxiety, somatic and depression subscales of the Crown-Crisp Experiential Index and lower serum carotene concentrations. The implications of these findings are discussed.

The 'state' of tobacco: Perceptions of tobacco among Appalachian youth in Kentucky

INTRODUCTION

In Appalachia, youth tobacco-use rates remain higher than the U.S. national average. Past research has indicated that several factors are related to high rates of tobacco use among Appalachian youth (e.g. low socioeconomic status, rural lifestyles). Of the Appalachian states, Kentucky has one of the highest rates of youth tobacco use. The aim of this study was to explore views of tobacco among Kentucky youth living in Appalachian counties.

METHODS

In Fall 2014 - Spring 2015, focus group interviews were conducted with middle and high school students (N=109) in Appalachian counties in Kentucky. Each focus group session included open-ended questions and was conducted by trained facilitators. Focus group transcriptions and field notes were analyzed for themes.

RESULTS

Study participants described an entrenched culture of tobacco. Three themes exemplified this culture. First, adult behavior served to enable youth tobacco use (e.g. teachers ignoring dip use in class, adults smoking with youth). Second, tobacco is easily accessible to youth (e.g. restrictions on youth sales are often ignored, family members provide). Third, symbols of tobacco are prevalent (e.g. festivals celebrating tobacco heritage, tobacco barns, and tobacco marketing logos).

CONCLUSIONS

Youth participants described a deeply rooted tobacco culture, which they believed was unlikely to change. Additional studies and health education efforts are needed in these rural communities. Further, stricter enforcement of tobacco sales and marketing restrictions may be helpful in protecting this vulnerable population.

The social patterning of electronic nicotine delivery system use among US adults

There is little research examining the social patterning of electronic nicotine delivery system (ENDS) use. This study investigated the association between socioeconomic status (SES) (education, income, and employment status) and current and former ENDS use. Data were collected from 2561 participants from the American Heart Association Tobacco Regulatory and Addiction Center (A-TRAC) online survey. Participants were 18-64 years old and reported demographic, SES, and ENDS use. Poisson regression was used to estimate prevalence ratios (PR 95% confidence interval-CI) of participants' current and former (vs. never) ENDS use. Models were adjusted for age, sex, sexual orientation, race/ethnicity, marital status, and reasons for ENDS use. In the unadjusted analysis, ENDS use was primarily patterned by education and employment status. College educated persons (vs. those with less than a high school diploma) had a 37% greater prevalence of current ENDS use (PR 1.37, 95% CI 1.20-1.55), and a 16% greater prevalence of former ENDS use (PR 1.16, 95% CI 1.06-1.28) in the fully-adjusted model. Persons with household incomes above $90 K (vs. less than $20,000) had a greater prevalence of current (PR 1.30, 95% CI 1.19-1.41) and former (PR 1.17, 95% CI 1.05-1.30) ENDS use. Those who were employed (vs. not employed) had a 13% greater prevalence of current ENDS use (PR 1.13, 95% CI 1.07-1.19) after full adjustment. Higher SES (vs. lower SES) persons were more likely to use ENDS.

New limits on Planck scale Lorentz violation in QED

Constraints on possible Lorentz symmetry violation (LV) of order E/M(Planck) for electrons and photons in the framework of effective field theory (EFT) are discussed. Using (i) the report of polarized MeV emission from GRB021206 and (ii) the absence of vacuum Cerenkov radiation from synchrotron electrons in the Crab Nebula, we improve previous bounds by 10(-10) and 10(-2), respectively. We also show that the LV parameters for positrons and electrons are different, discuss electron helicity decay, and investigate how prior constraints are modified by the relations between LV parameters implied by EFT.

Tobacco use and harm perceptions among Appalachian youth

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Over one-third had tried tobacco and over one-fifth had tried two or more products.

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Most participants recognized harms associated with conventional tobacco use.

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E-cigarettes were perceived as less harmful than conventional tobacco products.

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Smokers and polytobacco users had lower odds of indicating tobacco health risks.

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E-cigarette users were less likely to perceive e-cigarettes as harmful or addictive.

Appalachian youth tobacco use rates exceed the national average. Additional inquiry is needed to better understand youth product perceptions and use patterns. This study examined tobacco harm perceptions and their relationship with tobacco use among Appalachian youth. From 2014 to 2016, a survey of Appalachian middle and high school students (N = 1,136) was conducted. Tobacco harm perceptions were assessed by tobacco use status, categorized as never user, cigarette only user, smokeless only user, e-cigarette only user, or polytobacco user. Descriptive characteristics were compared by tobacco use status and harm perceptions. Adjusted multivariable logistic regression models assessed the relationship between tobacco use status and harm perceptions. Over one-third of participants were tobacco users (34.6%; 4.7% cigarette only users, 3.3% smokeless only users, 5.6% e-cigarette only users, and 21.0% polytobacco users). Approximately half agreed that e-cigarettes cause health problems (54.4%), and 64.7% agreed that e-cigarettes are addictive. Most participants (83.4–92.3%) agreed that smoking and smokeless tobacco cause health problems and are addictive. Tobacco users more often disagreed that tobacco products cause health problems than did never users. Compared to never users, e-cigarette only users were more likely to disagree that smoking (AOR: 2.99, 95% CI: 1.30–6.90) and e-cigarettes cause health problems (AOR: 2.79, 95% CI: 1.64–4.75) and that e-cigarettes cause addiction (AOR: 2.48, 95% CI: 1.48–4.16). Most youth were aware of health dangers associated with smoking, but perceptions were split on whether e-cigarettes were associated with health problems or addiction.

The findings indicate the need for additional youth tobacco use prevention efforts.

Fluorimetric method for simultaneous estimation of cortisol, corticosterone, and testosterone in plasma

The simultaneous estimation of steroids in plasma was carried out by the assay of cortisol, corticosterone, and testosterone. The method entails separation by means of thin layer chromatography, followed by conversion to a fluorophore and fluorimetric measurement. Its major advantages are its high specificity, its ability to detect unknown substances, and the ease with which it can be performed. The method has acceptable levels of accuracy and precision and the normal values obtained by it compare well with those given by methods in general use.

Adolescents' Concerns About School Violence or Shootings and Association With Depressive, Anxiety, and Panic Symptoms

IMPORTANCE

The prevalence of internalizing problems among US adolescents has risen in the past decade. The extent to which concerns about school violence or shootings are associated with risk of internalizing problems is unknown.

OBJECTIVE

To examine the prospective association of concern, worry, and stress related to school violence or shootings with internalizing problems and to examine sex and racial and ethnic differences in the magnitude of the associations.

DESIGN, SETTING, AND PARTICIPANTS

This longitudinal cohort study involved 3 surveys administered 6 months apart (fall of grade 11 [prebaseline]; spring of grade 11 [baseline]; and fall of grade 12 [follow-up]) from 2015 to 2016. Participants included 2263 students from 10 high schools in Los Angeles, California. Analyses were performed from April 29, 2020, to April 8, 2021.

EXPOSURES

Baseline self-reported level of concern, worry, and stress about shootings or violence at the student's school or other schools, each rated on 5-point scales (ranging from not at all [0] to extremely [4]) with a mean score calculated as a 3-item composite index rescaled into z-score standard deviation units.

MAIN OUTCOMES AND MEASURES

Surpassing clinically significant or borderline significant thresholds for major depressive disorder, generalized anxiety disorder, or panic disorder based on symptom ratings on the Revised Children's Anxiety and Depression Scale at 6-month follow-up.

RESULTS

Of the 2263 students included in the analyses (1250 [55.2%] girls; mean [SD] age, 16.5 [0.4] years), appreciable proportions reported being very or extremely concerned (850 0f 2226 [38.2%]), worried (703 of 2209 [31.8%]), or stressed (332 of 2183 [15.2%]) about shootings or violence at their school or other schools. After adjusting for prebaseline covariates, concerns about school violence or shootings were associated with clinically significant generalized anxiety symptoms (odds ratio [OR], 1.31; 95% CI, 1.15-1.50) and panic symptoms (OR, 1.18; 95% CI, 1.05-1.32), but not depressive symptoms (OR, 1.13; 95% CI, 0.99-1.30) at the 6-month follow-up. There was a significant association between concern with school violence or shootings and depressive symptoms for Black youth (OR, 3.15; 95% CI, 1.38-7.19) and non-Hispanic/Latinx White youth (OR, 1.62 [95% CI, 1.25-2.09]) but not for youth of other races and ethnicities (OR for Asian, 1.26 [95% CI, 0.86-1.85]; OR for Hispanic/Latinx, 0.94 [95% CI, 0.76-1.16]; OR for other, 0.93 [95% CI, 0.54-1.61]). Sex did not moderate these associations.

CONCLUSIONS AND RELEVANCE

The findings of this study suggest that concern, worry, and stress related to school violence or shootings may be risk factors for internalizing problems among adolescents, with variation in the strength of the association by race/ethnicity.

Change in distress about police brutality and substance use among young people, 2017-2020

BACKGROUND

It is unknown whether increasing attention to police brutality is a source of stress associated with substance use risk among young people.

METHODS

A longitudinal racially/ethnically diverse cohort from Los Angeles, California (n = 1797) completed baseline (2017; mean age: 17.9) and follow-up (2020; mean age: 21.2) surveys assessing level of concern, worry, and stress about police brutality (range: 0 'not at all' - 4 'extremely') and past 30-day nicotine, cannabis, alcohol, other drug, and number of substances used (0-19). Regression models, adjusted for demographic characteristics and baseline substance use, evaluated whether changes in distress about police brutality from 2017 to 2020 were associated with substance use in 2020 overall and stratified by race/ethnicity.

RESULTS

Distress about police brutality increased between 2017 (mean: 1.59) and 2020 (mean: 2.43) overall. Black/African American and Hispanic/Latino respondents consistently had the highest mean distress levels at both timepoints. In the full sample, each one-unit greater increase in distress about police brutality from 2017 to 2020 was associated with 11% higher odds of cannabis use, 13% higher odds of alcohol use, and 8% higher risk of using an additional substance for the number of substances used outcome. Race/ethnicity-stratified models indicated that greater increases in distress from 2017 to 2020 was associated with substance use among Black/African American, Hispanic, and multiracial respondents in 2020, but not Asian American/Pacific Islander and White respondents.

CONCLUSIONS

Distress about police brutality may be associated with substance use, particularly among certain racial/ethnic minority young people. Further investigation of whether police brutality affects health in disparity populations is needed.

Trends in prevalence and sociodemographic and geographic patterns of current menthol cigarette use among U.S. adults, 2005-2015

Despite overall reductions in U.S. smoking prevalence, prior evidence suggests similar reductions may not have occurred for menthol cigarette users. This study examines nationally representative current menthol and non-menthol cigarette use prevalence and trends for adults (18+) overall and by sociodemographic and geographic characteristics using the 2005 (n = 31,132), 2010 (n = 26,967), and 2015 (n = 33,541) National Health Interview Survey. Between 2005 and 2015, non-menthol cigarette use decreased overall (14.7% to 9.6%, p < 0.001) and within all sociodemographic and geographic subgroups analyzed (i.e., by sex, age, race/ethnicity, sexual orientation, education, family income, and geographic region), except non-Hispanic American Indians/Alaskan Natives (NH AI/AN) and non-Hispanic Others. Menthol cigarette use significantly decreased overall (5.3% to 4.4%, p < 0.001), and among females (5.6% to 4.6%); participants aged 18-24 (7.1% to 4.3%) and 35-54 (6.2% to 4.9%); non-Hispanic Whites (4.1% to 3.6%) and non-Hispanic Blacks (14.8% to 11.9%); participants with high school degrees/GEDs (7.0% to 5.9%); participants with a family income of $75,000 or higher (3.4% to 2.3%); and participants residing in the Northeast (6.0% to 4.3%). Menthol cigarette use remained stable or did not significantly decrease among males; adults aged 25-34 and 55 years and older; NH AI/ANs, NH Others, and Hispanics; participants with less than high school education, some college, or a college degree; participants with a family income below $75,000; and participants residing in the North Central/Midwest, South, and West. Given that menthol cigarette use did not significantly change or decrease for multiple subgroups, further restriction on menthol manufacturing may help reduce tobacco use disparities.

Unpacking the Non-Hispanic Other Category: Differences in Patterns of Tobacco Product Use Among Youth and Adults in the United States, 2009-2018

Studies investigating patterns of tobacco use by race often aggregate non-Black and non-Hispanic racial minorities into the "Other" category, masking important differences. Pooling 10 years (2009-2018) of National Survey on Drug Use and Health data (n = 52,424), we estimated the prevalence and proportion of individual tobacco product use and patterns of single, dual, and polytobacco use overall and by sex for youth (12-17) and adult (18 +) non-Hispanic Asian, American Indian/Alaska Native (AI/AN), Native Hawaiian/other Pacific Islander (NH/PI), and multiracial respondents. Cigarette prevalence was highest among AI/AN youth (8.6%) and adults (37.3%). For youth and adults, the AI/AN subgroup had the highest prevalence of single (9.2% youth, 35.8% adults) and dual (2.8% youth, 6.6% adults) use, followed by multiracial respondents. Furthermore, among tobacco users, AI/AN and multiracial youth and adults had the highest proportions of dual and poly use compared to other races. Appropriate tobacco prevention and cessation interventions should consider variation in tobacco use among non-Hispanic "Other" subgroups.

Perceived health risks of electronic nicotine delivery systems (ENDS) users: The role of cigarette smoking status

INTRODUCTION

Use of electronic nicotine delivery systems (ENDS) has increased markedly. We examined how current ENDS users differ in perceptions of tobacco and ENDS-related health risks as a function of cigarette smoking status.

METHODS

We classified 1329 current ENDS users completing a national online survey based on cigarette smoking status, and employed linear and logistic regression to assess group differences in perceptions of tobacco-related health risks.

RESULTS

The sample consisted of 38% Current Cigarette Smokers, 40% Former Cigarette Smokers, and 22% Non-Smokers. Our targeted recruitment strategy yielded a balance of key descriptive variables across participants. Significant differences were observed in race, employment and marital status across cigarette smoking status, but not in gender, education, income, or sexual orientation. Participants reported considerable perceived knowledge about health risks associated with tobacco use, but less regarding ENDS use. Current Smokers rated ENDS use as riskier than Non-Smokers, and considered cigarette use less risky for both users and bystanders. Current Smokers were more likely to perceive cardiovascular diseases, diabetes and cancer as the health risks associated with ENDS use. Former Smokers were more likely to perceive such risks with traditional tobacco use. Further, regardless of smoking status, perceived knowledge about the health risks of tobacco or ENDS use was positively associated with perceived likelihood of high risks of cardiovascular diseases and cancer.

CONCLUSIONS

Among current ENDS users, there were significant differences in perceived health risks based on cigarette smoking history. Improved health messaging can be achieved when cigarette smoking status is taken into account.

The contribution of research to racial health equity? Blame and responsibility in navigating the status quo of anti-black systemic racism

Thirty-seven years ago, the Secretary's Task Force on Black and Minority Health called attention to a "national paradox" of persistent Black-White health disparities despite overall health improvements for the nation (HHS, 1985). Subsequent updates to the "Heckler Report" came to the same conclusion; Black Americans continued to exhibit poorer health in comparison to White Americans (Satcher et al., 2005). Current population health statistics demonstrate Black-White health disparities comparable to 1985 (AHRQ, 2018; Shiels et al., 2021; Wall et al., 2018). Although psychological, behavioral, social, and economic factors all contribute to Black-White differences in health, there is a noticeable increase in discussions about the importance of systemic racism in producing racial health disparities. This article addresses three questions relevant to research on racism and the health of Black Americans: (1) Why has academic public health research on racism failed to reduce racial health disparities? (2) What can academic public health scientists do differently to reduce the impact of systemic racism on inequities among Black and White Americans? (3) What can Black Americans do in the face of present-day anti-Black systemic racism? We argue that to convert the vision of health equity into a visible reality, health equity research scientists must move beyond discussion, observation, and description. We also argue that to demonstrate progress in reducing racial health disparities, health equity scientists will need to work much more directly on eradicating racism as a fundamental cause of health differences between Black and White Americans. As scientists, the challenge we face is how to accomplish this mission without leaving the realm of science. Racism is a social determinant of Black health and social determinants are political problems. Political problems require political solutions.

Longitudinal associations between exclusive, dual, and polytobacco use and asthma among US youth

Little is known about the respiratory health effects of dual (two products) and polytobacco (three or more products) use among youth in the United States. Thus, we followed a longitudinal cohort of youth into adulthood using data from Waves 1-5 (2013-2019) of the Population Assessment of Tobacco and Health Study, examining incident asthma at each follow-up (Waves 2-5). We classified past 30-day tobacco use as 1) no products (never/former use), 2) exclusive cigarettes, 3) exclusive electronic nicotine delivery systems (ENDS), 4) exclusive other combustible (OC) tobacco products (cigars, hookah, pipe), 5) dual cigarettes/OC and ENDS, 6) dual cigarettes and OCs, and 7) polytobacco use (cigarettes, OCs, and ENDS). Using discrete time survival models, we analyzed the incidence of asthma across Waves 2-5, predicted by time-varying tobacco use lagged by one wave, and adjusted for potential baseline confounders. Asthma was reported by 574 of the 9141 respondents, with an average annual incidence of 1.44% (range 0.35% to 2.02%, Waves 2-5). In adjusted models, exclusive cigarette use (HR: 1.71, 95% CI: 1.11-2.64) and dual cigarette and OC use (HR: 2.78, 95% CI: 1.65-4.70) were associated with incident asthma compared to never/former use, while exclusive ENDS use (HR: 1.50, 95% CI: 0.92-2.44) and polytobacco use (HR: 1.95, 95% CI: 0.86-4.44) were not. To conclude, youth who use cigarettes with or without OCs had higher risk of incident asthma. Further longitudinal studies on the respiratory health effects of ENDS and dual/polytobacco use are needed as products continue to evolve.