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This study experimentally investigates reacting jets in cross-flow (RJICF), considering flame/shear layer offset, momentum flux ratio ($J$) and density ratio ($S$) effects. These results demonstrate that non-reacting JICF and RJICF can exhibit very similar or completely different dynamics and controlling physics, depending upon streamwise and radial flame location. Consistent with prior measurements of Getsinger et al. (Exp. Fluids, vol. 53 (3), 2012, pp. 783–801), spatial amplification rates of shear layer vortex (SLV) structures increased with decreasing $S$ for non-reacting cases. Similar $S$ dependencies exist for reacting cases in which the flame lay outside the jet shear layer, whose flow topology is also quite similar to non-reacting cases, albeit with reduced SLV growth rates. However, although the reacting cases have lower growth rates, these SLV structures ultimately reach approximately the same peak strength as in the non-reacting cases. Finally, the SLV decay rate in both non-reacting and reacting cases was found to similarly scale inversely with the initial SLV growth rate. As such, primarily inertial mechanisms govern SLV growth and decay for reacting cases where the flame lies outside the shear layer. In contrast, very different behaviour is exhibited by reacting cases where the flame lies inside the shear layer, where the locally increased viscosity exerts significant influences. In these reacting cases, SLV roll-up is completely suppressed and the entire jet column undulates over a long length scale relative to the jet diameter. As such, the relative roles of inertial and viscous mechanisms in controlling combustion influences on the SLV dynamics, changes markedly with shear layer–flame offset.
Alzheimer’s disease (AD) is highly heritable, and AD polygenic risk scores (AD-PRSs) have been derived from genome-wide association studies. However, the nature of genetic influences very early in the disease process is still not well known. Here we tested the hypothesis that an AD-PRSs would be associated with changes in episodic memory and executive function across late midlife in men who were cognitively unimpaired at their baseline midlife assessment..
We examined 1168 men in the Vietnam Era Twin Study of Aging (VETSA) who were cognitively normal (CN) at their first of up to three assessments across 12 years (mean ages 56, 62, and 68). Latent growth models of episodic memory and executive function were based on 6–7 tests/subtests. AD-PRSs were based on Kunkle et al. (Nature Genetics, 51, 414–430, 2019), p < 5×10−8 threshold.
AD-PRSs were correlated with linear slopes of change for both cognitive abilities. Men with higher AD-PRSs had steeper declines in both memory (r = −.19, 95% CI [−.35, −.03]) and executive functioning (r = −.27, 95% CI [−.49, −.05]). Associations appeared driven by a combination of APOE and non-APOE genetic influences.
Memory is most characteristically impaired in AD, but executive functions are one of the first cognitive abilities to decline in midlife in normal aging. This study is among the first to demonstrate that this early decline also relates to AD genetic influences, even in men CN at baseline.
From 2014 to 2020, we compiled radiocarbon ages from the lower 48 states, creating a database of more than 100,000 archaeological, geological, and paleontological ages that will be freely available to researchers through the Canadian Archaeological Radiocarbon Database. Here, we discuss the process used to compile ages, general characteristics of the database, and lessons learned from this exercise in “big data” compilation.
The present study examined patterns of stability and change in loneliness across adolescence. Data were drawn from the Environmental Risk (E-Risk) Longitudinal Twin Study, a UK population-representative cohort of 2,232 individuals born in 1994 and 1995. Loneliness was assessed when participants were aged 12 and 18. Loneliness showed modest stability across these ages (r = .25). Behavioral genetic modeling indicated that stability in loneliness was explained largely by genetic influences (66%), while change was explained by nonshared environmental effects (58%). Individuals who reported loneliness at both ages were broadly similar to individuals who only reported it at age 18, with both groups at elevated risk of mental health problems, physical health risk behaviors, and education and employment difficulties. Individuals who were lonely only at age 12 generally fared better; however, they were still more likely to finish school with lower qualifications. Positive family influences in childhood predicted reduced risk of loneliness at age 12, while negative peer experiences increased the risk. Together, the findings show that while early adolescent loneliness does not appear to exert a cumulative burden when it persists, it is nonetheless a risk for a range of concomitant impairments, some of which can endure.
Adolescent e-cigarette use has been labeled an epidemic and alcohol use during this developmental period is associated with deleterious outcomes. Though specific temperamental dimensions have been shown to predict substance use, profiles of temperament have rarely been examined as predictors. This study examines dimensions and profiles of adolescent temperament as predictors of early use of e-cigarettes and alcohol. The sample was comprised of adolescent (62.07% female, 87.59% White, 82.76% Hispanic/Latinx)/caregiver dyads (N = 146) who completed the first two timepoints (M age at second timepoint = 16.16, SD = 0.68) of a longitudinal adolescent substance use study. Models showed parent-reported effortful control predicted protection against adolescent use of e-cigarettes, whereas adolescent report of effortful control predicted protection against alcohol use. Though dissimilar in temperamental pattern, three profiles emerged from both parent- and adolescent-report-based latent profile analysis models. Adolescents characterized by parents as displaying a Resilient profile had greater odds of e-cigarette use than those characterized by a Reserved profile, whereas adolescents who self-characterized as Mixed-type had markedly greater odds of alcohol use than those who self-characterized as Resilient. Utilization of temperamental profiles may aid in identification of particularly vulnerable subgroups of adolescents who may benefit from relevant preventative programing.
Schmid and Mullins present what they call ‘the Aloneness Argument’ for the inconsistency of four theses from classical theism: the doctrine of divine simplicity, the doctrine of divine omniscience, the claim that God is free to create or not to create, and the claim that it is possible that God and nothing but God exist. We deny that they have shown an inconsistency between these theses. We maintain that, depending on how certain premises are interpreted, one or another premise is false. We also offer a positive proposal regarding a simple God's knowledge that he is alone in a world where he doesn't create anything.
Catatonia, a severe neuropsychiatric syndrome, has few studies of sufficient scale to clarify its epidemiology or pathophysiology. We aimed to characterise demographic associations, peripheral inflammatory markers and outcome of catatonia.
Electronic healthcare records were searched for validated clinical diagnoses of catatonia. In a case–control study, demographics and inflammatory markers were compared in psychiatric inpatients with and without catatonia. In a cohort study, the two groups were compared in terms of their duration of admission and mortality.
We identified 1456 patients with catatonia (of whom 25.1% had two or more episodes) and 24 956 psychiatric inpatients without catatonia. Incidence was 10.6 episodes of catatonia per 100 000 person-years. Patients with and without catatonia were similar in sex, younger and more likely to be of Black ethnicity. Serum iron was reduced in patients with catatonia [11.6 v. 14.2 μmol/L, odds ratio (OR) 0.65 (95% confidence interval (CI) 0.45–0.95), p = 0.03] and creatine kinase was raised [2545 v. 459 IU/L, OR 1.53 (95% CI 1.29–1.81), p < 0.001], but there was no difference in C-reactive protein or white cell count. N-Methyl-d-aspartate receptor antibodies were significantly associated with catatonia, but there were small numbers of positive results. Duration of hospitalisation was greater in the catatonia group (median: 43 v. 25 days), but there was no difference in mortality after adjustment.
In the largest clinical study of catatonia, we found catatonia occurred in approximately 1 per 10 000 person-years. Evidence for a proinflammatory state was mixed. Catatonia was associated with prolonged inpatient admission but not with increased mortality.
The COVID-19 pandemic has placed significant strain on emergency departments (EDs) that were not designed to care for many patients who may be highly contagious. This report outlines how a busy urban ED was adapted to prepare for COVID-19 via 3 primary interventions: (1) creating an open-air care space in the ambulance bay to cohort, triage, and rapidly test patients with suspected COVID-19, (2) quickly constructing temporary doors on all open treatment rooms, and (3) adapting and expanding the waiting room. This description serves as a model by which other EDs can repurpose their own care spaces to help ensure safety of their patients and health care workers.
In the early phase of the coronavirus disease 2019 (COVID-19) pandemic, United States Emergency Medical Services (EMS) experienced a decrease in calls, and at the same time, an increase in out-of-hospital deaths. This finding led to a concern for the implications of potential delays in care for the obstetric population.
This study examines the impact of the pandemic on prehospital care amongst pregnant women.
A retrospective observational study was conducted comparing obstetric-related EMS activations in Maryland (USA) during the pandemic (March 10-July 20, 2020) to a pre-pandemic period (March 10-July 20, 2019). Comparative analysis was used to analyze the difference in frequency and acuity of calls between the two periods.
There were fewer obstetric-related EMS encounters during the pandemic compared to the year prior (daily average during the pandemic 12.5 [SD = 3.8] versus 14.6 [SD = 4.1] pre-pandemic; P <.001), although the percent of total female encounters remained unchanged (1.6% in 2020 versus 1.5% in 2019; P = .091). Key indicators of maternal status were not significantly different between the two periods. African-American women represented a disproportionately high percentage of obstetric-related activations (36.2% in 2019 and 34.8% in 2020).
In this state-wide analysis of EMS calls in Maryland early in the pandemic, no significant differences existed in the utilization of EMS by pregnant women. Prehospital EMS activations amongst pregnant women in Maryland only decreased slightly without an increase in acuity. Of note, over-representation by African-American women compared to population statistics raises concern for broader systemic differences in access to obstetric care.
A robust economy is assumed to bolster leaders' standing. This ignores how benefits of growth are distributed. Extending the partisan models of economic voting, we theorize executives are more likely rewarded when gains from growth go to their constituents. Analyses of presidential approval in 18 Latin American countries support our pro-constituency model of accountability. When economic inequality is high, growth concentrates among the rich, and approval of right-of-center presidents is higher. Leftist presidents benefit from growth when gains are more equally distributed. Further analyses show growth and inequality inform perceptions of personal finances differently based on wealth, providing a micro-mechanism behind the aggregate findings. Study results imply that the economy is not purely a valence issue, but also a position issue.
The Subglacial Antarctic Lakes Scientific Access (SALSA) Project accessed Mercer Subglacial Lake using environmentally clean hot-water drilling to examine interactions among ice, water, sediment, rock, microbes and carbon reservoirs within the lake water column and underlying sediments. A ~0.4 m diameter borehole was melted through 1087 m of ice and maintained over ~10 days, allowing observation of ice properties and collection of water and sediment with various tools. Over this period, SALSA collected: 60 L of lake water and 10 L of deep borehole water; microbes >0.2 μm in diameter from in situ filtration of ~100 L of lake water; 10 multicores 0.32–0.49 m long; 1.0 and 1.76 m long gravity cores; three conductivity–temperature–depth profiles of borehole and lake water; five discrete depth current meter measurements in the lake and images of ice, the lake water–ice interface and lake sediments. Temperature and conductivity data showed the hydrodynamic character of water mixing between the borehole and lake after entry. Models simulating melting of the ~6 m thick basal accreted ice layer imply that debris fall-out through the ~15 m water column to the lake sediments from borehole melting had little effect on the stratigraphy of surficial sediment cores.
CHD affects over 1 million children in the United States. Studies show decreased mortality from CHD with newborn cardiac screening. California began a screening programme on 1 July, 2013. We evaluated the effect of mandatory screening on surgical outcomes at Loma Linda University Children’s Hospital since 1 July, 2013.
We evaluated all infants having congenital heart surgery at Loma Linda University Children’s Hospital between 1 July, 2013 and 31 December, 2018. Primary target diagnoses include hypoplastic left heart syndrome, pulmonary atresia with intact ventricular septum, tetralogy of Fallot, total anomalous pulmonary venous return, transposition of the great arteries, tricuspid atresia, and truncus arteriosus. Secondary target diagnoses include aortic coarctation, double outlet right ventricle, Ebstein anomaly, interrupted aortic arch, and single ventricle. Patients were stratified by timing of diagnosis (pre-screen, screen positive, and screen negative). Primary end points were post-operative length of stay, operative mortality, absolute mortality, and actuarial survival.
The cohort included 274 infants. Of these, 79% were diagnosed prior to screening (46% prenatally). Only 38% of those screened were positive, with 13% of the cohort having a “missed diagnosis.”
Primary targets were more likely to be diagnosed by screening (53%), while secondary targets were unlikely to be diagnosed by screening (10%) (p = 0.004). Outcomes such as length of stay, operative mortality, and actuarial survival were not different based on timing of diagnosis (p > 0.05). Despite late diagnosis, those not diagnosed until after screening did not have adverse outcomes.
There is substantial evidence that voters’ choices are shaped by assessments of the state of the economy and that these assessments, in turn, are influenced by the news. But how does the economic news track the welfare of different income groups in an era of rising inequality? Whose economy does the news cover? Drawing on a large new dataset of US news content, we demonstrate that the tone of the economic news strongly and disproportionately tracks the fortunes of the richest households, with little sensitivity to income changes among the non-rich. Further, we present evidence that this pro-rich bias emerges not from pro-rich journalistic preferences but, rather, from the interaction of the media’s focus on economic aggregates with structural features of the relationship between economic growth and distribution. The findings yield a novel explanation of distributionally perverse electoral patterns and demonstrate how distributional biases in the economy condition economic accountability.
Deaf readers may have larger perceptual spans than ability-matched hearing native English readers, allowing them to read more efficiently (Belanger & Rayner, 2015). To further test the hypothesis that deaf and hearing readers have different perceptual spans, the current study uses eye-movement data from two experiments in which deaf American Sign Language–English bilinguals, hearing native English speakers, and hearing Chinese–English bilinguals read semantically unrelated sentences and answered comprehension questions after a proportion of them. We analyzed skip rates, fixation times, and accuracy on comprehension questions. In addition, we analyzed how lexical properties of words affected skipping behavior and fixation durations. Deaf readers skipped words more often than native English speakers, who skipped words more often than Chinese–English bilinguals. Deaf readers had shorter first-pass fixation times than the other two groups. All groups’ skipping behaviors were affected by lexical frequency. Deaf readers’ comprehension did not differ from hearing Chinese–English bilinguals, despite greater skipping and shorter fixation times. Overall, the eye-tracking findings align with Belanger’s word processing efficiency hypothesis. Effects of lexical frequency on skipping behavior indicated further that eye movements during reading remain under cognitive control in deaf readers.
This SHEA white paper identifies knowledge gaps and challenges in healthcare epidemiology research related to coronavirus disease 2019 (COVID-19) with a focus on core principles of healthcare epidemiology. These gaps, revealed during the worst phases of the COVID-19 pandemic, are described in 10 sections: epidemiology, outbreak investigation, surveillance, isolation precaution practices, personal protective equipment (PPE), environmental contamination and disinfection, drug and supply shortages, antimicrobial stewardship, healthcare personnel (HCP) occupational safety, and return to work policies. Each section highlights three critical healthcare epidemiology research questions with detailed description provided in supplementary materials. This research agenda calls for translational studies from laboratory-based basic science research to well-designed, large-scale studies and health outcomes research. Research gaps and challenges related to nursing homes and social disparities are included. Collaborations across various disciplines, expertise and across diverse geographic locations will be critical.
The present study used a longitudinal and discordant twin design to explore in depth the developmental associations between victimization and loneliness from mid-childhood to young adulthood. The data were drawn from the Environmental Risk (E-Risk) Longitudinal Twin Study, a birth cohort of 2,232 individuals born in England and Wales during 1994–1995. Diverse forms of victimization were considered, differing across context, perpetrator, and timing of exposure. The results indicated that exposure to different forms of victimization was associated with loneliness in a dose–response manner. In childhood, bullying victimization was uniquely associated with loneliness, over and above concurrent psychopathology, social isolation, and genetic risk. Moreover, childhood bullying victimization continued to predict loneliness in young adulthood, even in the absence of ongoing victimization. Within-twin pair analyses further indicated that this longitudinal association was explained by genetic confounds. In adolescence, varied forms of victimization were correlated with young adult loneliness, with maltreatment, neglect, and cybervictimization remaining robust to controls for genetic confounds. These findings indicate that vulnerability to loneliness in victimized young people varies according to the specific form of victimization in question, and also to the developmental period in which it was experienced.
This work investigated the photophysical pathways for light absorption, charge generation, and charge separation in donor–acceptor nanoparticle blends of poly(3-hexylthiophene) and indene-C60-bisadduct. Optical modeling combined with steady-state and time-resolved optoelectronic characterization revealed that the nanoparticle blends experience a photocurrent limited to 60% of a bulk solution mixture. This discrepancy resulted from imperfect free charge generation inside the nanoparticles. High-resolution transmission electron microscopy and chemically resolved X-ray mapping showed that enhanced miscibility of materials did improve the donor–acceptor blending at the center of the nanoparticles; however, a residual shell of almost pure donor still restricted energy generation from these nanoparticles.
To understand hospital policies and practices as the COVID-19 pandemic accelerated, the Society for Healthcare Epidemiology of America (SHEA) conducted a survey through the SHEA Research Network (SRN). The survey assessed policies and practices around the optimization of personal protection equipment (PPE), testing, healthcare personnel policies, visitors of COVID-19 patients in relation to procedures, and types of patients. Overall, 69 individual healthcare facilities responded in the United States and internationally, for a 73% response rate.