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Supersymmetry is an extension of the successful Standard Model of particle physics; it relies on the principle that fermions and bosons are related by a symmetry, leading to an elegant predictive structure for quantum field theory. This textbook provides a comprehensive and pedagogical introduction to supersymmetry and spinor techniques in quantum field theory. By utilising the two-component spinor formalism for fermions, the authors provide many examples of practical calculations relevant for collider physics signatures, anomalies, and radiative corrections. They present in detail the component field and superspace formulations of supersymmetry and explore related concepts, including the theory of extended Higgs sectors, models of grand unification, and the origin of neutrino masses. Numerous exercises are provided at the end of each chapter. Aimed at graduate students and researchers, this volume provides a clear and unified treatment of theoretical concepts that are at the frontiers of high energy particle physics.
Studies have reported that minorities are disproportionately impacted by the COVID-19 pandemic. Few studies have elucidated the lived experiences of African American older adults, and the resiliency displayed in combatting the COVID-19 pandemic and other disasters.
Methods:
This study used 4 recorded focus groups with 26 African American older adults who have spent most of their lives living in Houston, Texas to assess safety, economic, and health concerns related to the pandemic and similarities or differences with other types of disasters that are specific to Houston/ the Gulf Region of Texas, such as Hurricane Harvey.
Results:
Key themes emerged from the thematic analysis: 1) previous disasters provided important coping and preparation skills, although each occurrence was still a major stressor, 2) while telehealth was a significant benefit, regular health maintenance and chronic disease management were not completed during the COVID-19 pandemic, 3) information from the federal and state authorities were inconsistent and spurred fear and anxiety, 4) participants experienced few to no disruptions to their income but were heavily called on to support family members, and 5) participants experienced anxiety and isolation, but many used existing social connections to cope.
Conclusions:
These findings demonstrate how African American older adults navigate disaster response and recovery through experience and community. Providing unambiguous information to older adults could prove useful in preparing for future disaster events and coping with disasters.
Posttraumatic Stress Disorder (PTSD) tends to co-occur with greater alcohol consumption as well as alcohol use disorder (AUD). However, it is unknown whether the same etiologic factors that underlie PTSD-alcohol-related problems comorbidity also contribute to PTSD- alcohol consumption.
Methods
We used summary statistics from large-scale genome-wide association studies (GWAS) of European-ancestry (EA) and African-ancestry (AA) participants to estimate genetic correlations between PTSD and a range of alcohol consumption-related and alcohol-related problems phenotypes.
Results
In EAs, there were positive genetic correlations between PTSD phenotypes and alcohol-related problems phenotypes (e.g. Alcohol Use Disorders Identification Test (AUDIT) problem score) (rGs: 0.132−0.533, all FDR adjusted p < 0.05). However, the genetic correlations between PTSD phenotypes and alcohol consumption -related phenotypes (e.g. drinks per week) were negatively associated or non-significant (rGs: −0.417 to −0.042, FDR adjusted p: <0.05-NS). For AAs, the direction of correlations was sometimes consistent and sometimes inconsistent with that in EAs, and the ranges were larger (rGs for alcohol-related problems: −0.275 to 0.266, FDR adjusted p: NS, alcohol consumption-related: 0.145–0.699, FDR adjusted p: NS).
Conclusions
These findings illustrate that the genetic associations between consumption and problem alcohol phenotypes and PTSD differ in both strength and direction. Thus, the genetic factors that may lead someone to develop PTSD and high levels of alcohol consumption are not the same as those that lead someone to develop PTSD and alcohol-related problems. Discussion around needing improved methods to better estimate heritabilities and genetic correlations in diverse and admixed ancestry samples is provided.
The transfer rate for patients from an Alternate Care Site (ACS) back to a hospital may serve as a metric of appropriate patient selection and the ability of an ACS to treat moderate to severely ill patients accepted from overwhelmed health-care systems. During the coronavirus infectious disease 2019 (COVID-19) pandemic, hospitals worldwide experienced acute surges of patients presenting with acute respiratory failure.
Methods:
An ACS in Imperial County, California was re-established in November 2020 to help decompress 2 local hospitals experiencing surges of COVID-19 cases. The patients treated often had multiple comorbid illnesses and required a median supplemental oxygen of 3 L/min (LPM) on admission. Numerous interventions were initiated during a 2-wk period to improve clinical care delivery.
Results:
The objectives of this retrospective observational study are to evaluate the impact of these clinical and staff interventions at an ACS on the transfer rate and to provide issues to consider for future ACS sites managing COVID-19 patients.
Conclusions:
The data suggest that continuous, real-time process-improvement interventions helped reduce the transfer rate back to hospitals from 36.7% to 14.5% and that an ACS is a viable option for managing symptomatic COVID-19 positive patients requiring hospital-level care when hospitals are overburdened.
Higher inflammation has been linked to poor physical and mental health outcomes, and mortality, but few studies have rigorously examined whether changes in perceived stress and depressive symptoms are associated with increased inflammation within family caregivers and non-caregivers in a longitudinal design.
Design:
Longitudinal Study.
Setting:
REasons for Geographic And Racial Differences in Stroke cohort study.
Participants:
Participants included 239 individuals who were not caregivers at baseline but transitioned to providing substantial and sustained caregiving over time. They were initially matched to 241 non-caregiver comparisons on age, sex, race, education, marital status, self-rated health, and history of cardiovascular disease. Blood was drawn at baseline and approximately 9.3 years at follow-up for both groups.
Measurements:
Perceived Stress Scale, Center for Epidemiological Studies-Depression, inflammatory biomarkers, including high-sensitivity C-reactive protein, D dimer, tumor necrosis factor alpha receptor 1, interleukin (IL)-2, IL-6, and IL-10 taken at baseline and follow-up.
Results:
Although at follow-up, caregivers showed significantly greater worsening in perceived stress and depressive symptoms compared to non-caregivers, there were few significant associations between depressive symptoms or perceived stress on inflammation for either group. Inflammation, however, was associated with multiple demographic and health variables, including age, race, obesity, and use of medications for hypertension and diabetes for caregivers and non-caregivers.
Conclusions:
These findings illustrate the complexity of studying the associations between stress, depressive symptoms, and inflammation in older adults, where these associations may depend on demographic, disease, and medication effects. Future studies should examine whether resilience factors may prevent increased inflammation in older caregivers.
Psychiatric mother and baby units (MBUs) are recommended for severe perinatal mental illness, but effectiveness compared with other forms of acute care remains unknown.
Aims
We hypothesised that women admitted to MBUs would be less likely to be readmitted to acute care in the 12 months following discharge, compared with women admitted to non-MBU acute care (generic psychiatric wards or crisis resolution teams (CRTs)).
Method
Quasi-experimental cohort study of women accessing acute psychiatric care up to 1 year postpartum in 42 healthcare organisations across England and Wales. Primary outcome was readmission within 12 months post-discharge. Propensity scores were used to account for systematic differences between MBU and non-MBU participants. Secondary outcomes included assessment of cost-effectiveness, experience of services, unmet needs, perceived bonding, observed mother–infant interaction quality and safeguarding outcome.
Results
Of 279 women, 108 (39%) received MBU care, 62 (22%) generic ward care and 109 (39%) CRT care only. The MBU group (n = 105) had similar readmission rates to the non-MBU group (n = 158) (aOR = 0.95, 95% CI 0.86–1.04, P = 0.29; an absolute difference of −5%, 95% CI −14 to 4%). Service satisfaction was significantly higher among women accessing MBUs compared with non-MBUs; no significant differences were observed for any other secondary outcomes.
Conclusions
We found no significant differences in rates of readmission, but MBU advantage might have been masked by residual confounders; readmission will also depend on quality of care after discharge and type of illness. Future studies should attempt to identify the effective ingredients of specialist perinatal in-patient and community care to improve outcomes.
OBJECTIVES/GOALS: We aimed to determine if GLP-1 receptor agonists exert beneficial effects on surrogate measures of cardiovascular function independently of weight loss. Our objective was to compare the outcomes between GLP-1 receptor agonist treatment versus a similar drug without cardiovascular benefit versus weight loss through diet alone. METHODS/STUDY POPULATION: We enrolled 88 individuals with obesity (BMI ≥ 30kg/m2) and pre-diabetes and randomized them in a 2:1:1 ratio to 14 weeks of the GLP-1 receptor agonist liraglutide, the dipeptidyl peptidase-4 inhibitor sitagliptin, or hypocaloric diet. Sitagliptin blocks degradation of endogenous GLP-1 but does not cause weight loss or lower adverse cardiovascular outcomes. Treatment was double-blinded and placebo-controlled for drug, and unblinded for diet. Primary endpoints were flow-mediated dilation (FMD) to assess endothelial vasodilatory function, and plasminogen activator inhibitor-1 (PAI-1) to assess endothelial fibrinolytic function. We used a general linear model for each outcome and included gender as a covariate for FMD. Baseline characteristics were similar. Mean age was 50, with 32% men and 13% black. RESULTS/ANTICIPATED RESULTS: At 14 weeks, diet and liraglutide caused weight loss (diet -4.3 ± 3.2 kg, P<0.01; liraglutide -2.7 ± 3.2, P<0.01), while sitagliptin did not (-0.7 ± 2.0, P=0.17). Diet did not improve FMD at 14 weeks compared to baseline (+0.9%, 95% CI [-1.5, 3.3], P=0.46). FMD tended to increase after liraglutide and sitagliptin but was not significant (liraglutide +1.2 [-0.3, 2.8], P=0.12; sitagliptin +1.6 [-0.6, 3.8], P=0.15). Given that liraglutide and sitagliptin work through the same GLP-1 pathway, we combined the liraglutide and sitagliptin groups for overall effect on FMD, which was significantly improved from baseline (+1.4 [0.1, 2.8], P=0.04). Diet and liraglutide improved PAI-1 at 14 weeks (diet -4.4U/mL, [-8.5, -0.2], P=0.04; liraglutide -3.4 [-6.0, -0.7], P=0.01), while sitagliptin did not (-1.4 [-5.1, 2.3], P=0.46). DISCUSSION/SIGNIFICANCE: Activation of the GLP-1 pathway by liraglutide or sitagliptin improves FMD independent of weight loss, while PAI-1 improvement is weight-loss dependent and is only seen after liraglutide or diet. Our study suggests the cardiovascular benefit of liraglutide may be due to combined improvements in endothelial vasodilatory and fibrinolytic function.
Recurrent laryngeal nerve injury leading to vocal cord paralysis is a known complication of cardiothoracic surgery. Its occurrence during interventional catheterisation procedures has been documented in case reports, but there have been no studies to determine an incidence.
Objective:
To establish the incidence of left recurrent laryngeal nerve injury leading to vocal cord paralysis after left pulmonary artery stenting, patent ductus arteriosus device closure and the combination of the procedures either consecutively or simultaneously.
Methods:
Members of the Congenital Cardiovascular Interventional Study Consortium were asked to perform a retrospective analysis to identify cases of recurrent laryngeal nerve injury after the aforementioned procedures. Twelve institutions participated in the analysis. They also contributed the total number of each procedure performed at their respective institutions for statistical purposes.
Results:
Of the 1337 patients who underwent left pulmonary artery stent placement, six patients (0.45%) had confirmed vocal cord paralysis. 4001 patients underwent patent ductus arteriosus device closure, and two patients (0.05%) developed left vocal cord paralysis. Patients who underwent both left pulmonary artery stent placement and patent ductus arteriosus device closure had the highest incidence of vocal cord paralysis which occurred in 4 of the 26 patients (15.4%). Overall, 92% of affected patients in our study population had resolution of symptoms.
Conclusion:
Recurrent laryngeal nerve injury is a rare complication of left pulmonary artery stent placement or patent ductus arteriosus device closure. However, the incidence is highest in patients undergoing both procedures either consecutively or simultaneously. Additional research is necessary to determine contributing factors that might reduce the risk of recurrent laryngeal nerve injury.
Much evidence shows that economic inequality within States has increased dramatically during the current round of globalization, since about 1980. This has occurred even as the level of absolute poverty has significantly declined, as has inequality among States I and among individuals worldwide (Bourguignon 2015; Milanovic 2016). Yet the effect of economic inequality on economic and social human rights varies across States.
The behaviour of a viscous drop squeezed between two horizontal planes (a squeezed Hele-Shaw cell) is treated by both theory and experiment. When the squeezing force $F$ is constant and surface tension is neglected, the theory predicts ultimate growth of the radius $a\sim t^{1/8}$ with time $t$. This theory is first reviewed and found to be in excellent agreement with experiment. Surface tension at the drop boundary reduces the interior pressure, and this effect is included in the analysis, although it is negligibly small in the squeezing experiments. An initially elliptic drop tends to become circular as $t$ increases. More generally, the circular evolution is found to be stable under small perturbations. If, on the other hand, the force is reversed ($F<0$), so that the plates are drawn apart (the ‘contraction’, or ‘lifting plate’, problem), the boundary of the drop is subject to a fingering instability on a scale determined by surface tension. The effect of a trapped air bubble at the centre of the drop is then considered. The annular evolution of the drop under constant squeezing is still found to follow a ‘one-eighth’ power law, but this is unstable, the instability originating at the boundary of the air bubble, i.e. the inner boundary of the annulus. The air bubble is realised experimentally in two ways: first by simply starting with the drop in the form of an annulus, as nearly circular as possible; and second by forcing four initially separate drops to expand and merge, a process that involves the resolution of ‘contact singularities’ by surface tension. If the plates are drawn apart, the evolution is still subject to the fingering instability driven from the outer boundary of the annulus. This instability is realised experimentally by levering the plates apart at one corner: fingering develops at the outer boundary and spreads rapidly to the interior as the levering is slowly increased. At a later stage, before ultimate rupture of the film and complete separation of the plates, fingering spreads also from the boundary of any interior trapped air bubble, and small cavitation bubbles appear in the very low-pressure region, far from the point of leverage. This exotic behaviour is discussed in the light of the foregoing theoretical analysis.
Studying phenotypic and genetic characteristics of age at onset (AAO) and polarity at onset (PAO) in bipolar disorder can provide new insights into disease pathology and facilitate the development of screening tools.
Aims
To examine the genetic architecture of AAO and PAO and their association with bipolar disorder disease characteristics.
Method
Genome-wide association studies (GWASs) and polygenic score (PGS) analyses of AAO (n = 12 977) and PAO (n = 6773) were conducted in patients with bipolar disorder from 34 cohorts and a replication sample (n = 2237). The association of onset with disease characteristics was investigated in two of these cohorts.
Results
Earlier AAO was associated with a higher probability of psychotic symptoms, suicidality, lower educational attainment, not living together and fewer episodes. Depressive onset correlated with suicidality and manic onset correlated with delusions and manic episodes. Systematic differences in AAO between cohorts and continents of origin were observed. This was also reflected in single-nucleotide variant-based heritability estimates, with higher heritabilities for stricter onset definitions. Increased PGS for autism spectrum disorder (β = −0.34 years, s.e. = 0.08), major depression (β = −0.34 years, s.e. = 0.08), schizophrenia (β = −0.39 years, s.e. = 0.08), and educational attainment (β = −0.31 years, s.e. = 0.08) were associated with an earlier AAO. The AAO GWAS identified one significant locus, but this finding did not replicate. Neither GWAS nor PGS analyses yielded significant associations with PAO.
Conclusions
AAO and PAO are associated with indicators of bipolar disorder severity. Individuals with an earlier onset show an increased polygenic liability for a broad spectrum of psychiatric traits. Systematic differences in AAO across cohorts, continents and phenotype definitions introduce significant heterogeneity, affecting analyses.
Alcohol use disorder (AUD) and schizophrenia (SCZ) frequently co-occur, and large-scale genome-wide association studies (GWAS) have identified significant genetic correlations between these disorders.
Methods
We used the largest published GWAS for AUD (total cases = 77 822) and SCZ (total cases = 46 827) to identify genetic variants that influence both disorders (with either the same or opposite direction of effect) and those that are disorder specific.
Results
We identified 55 independent genome-wide significant single nucleotide polymorphisms with the same direction of effect on AUD and SCZ, 8 with robust effects in opposite directions, and 98 with disorder-specific effects. We also found evidence for 12 genes whose pleiotropic associations with AUD and SCZ are consistent with mediation via gene expression in the prefrontal cortex. The genetic covariance between AUD and SCZ was concentrated in genomic regions functional in brain tissues (p = 0.001).
Conclusions
Our findings provide further evidence that SCZ shares meaningful genetic overlap with AUD.
In the absence of evidence of acute cerebral herniation, normal ventilation is recommended for patients with traumatic brain injury (TBI). Despite this recommendation, ventilation strategies vary during the initial management of patients with TBI and may impact outcome. The goal of this systematic review was to define the best evidence-based practice of ventilation management during the initial resuscitation period.
Methods:
A literature search of PubMed, CINAHL, and SCOPUS identified studies from 2009 through 2019 addressing the effects of ventilation during the initial post-trauma resuscitation on patient outcomes.
Results:
The initial search yielded 899 articles, from which 13 were relevant and selected for full-text review. Six of the 13 articles met the inclusion criteria, all of which reported on patients with TBI. Either end-tidal carbon dioxide (ETCO2) or partial pressure carbon dioxide (PCO2) were the independent variables associated with mortality. Decreased rates of mortality were reported in patients with normal PCO2 or ETCO2.
Conclusions:
Normoventilation, as measured by ETCO2 or PCO2, is associated with decreased mortality in patients with TBI. Preventing hyperventilation or hypoventilation in patients with TBI during the early resuscitation phase could improve outcome after TBI.
Markedly elevated adverse mental health symptoms were widely observed early in the coronavirus disease-2019 (COVID-19) pandemic. Unlike the U.S., where cross-sectional data indicate anxiety and depression symptoms have remained elevated, such symptoms reportedly declined in the U.K., according to analysis of repeated measures from a large-scale longitudinal study. However, nearly 40% of U.K. respondents (those who did not complete multiple follow-up surveys) were excluded from analysis, suggesting that survivorship bias might partially explain this discrepancy. We therefore sought to assess survivorship bias among participants in our longitudinal survey study as part of The COVID-19 Outbreak Public Evaluation (COPE) Initiative.
Methods
Survivorship bias was assessed in 4039 U.S. respondents who completed surveys including the assessment of mental health as part of The COPE Initiative in April 2020 and were invited to complete follow-up surveys. Participants completed validated screening instruments for symptoms of anxiety, depression and insomnia. Survivorship bias was assessed for (1) demographic differences in follow-up survey participation, (2) differences in initial adverse mental health symptom prevalence adjusted for demographic factors and (3) differences in follow-up survey participation based on mental health experiences adjusted for demographic factors.
Results
Adjusting for demographics, individuals who completed only one or two out of four surveys had significantly higher prevalence of anxiety and depression symptoms in April 2020 (e.g. one-survey v. four-survey, anxiety symptoms, adjusted prevalence ratio [aPR]: 1.30, 95% confidence interval [CI]: 1.08–1.55, p = 0.0045; depression symptoms, aPR: 1.43, 95% CI: 1.17–1.75, p = 0.00052). Moreover, individuals who experienced incident anxiety or depression symptoms had significantly higher adjusted odds of not completing follow-up surveys (adjusted odds ratio [aOR]: 1.68, 95% CI: 1.22–2.31, p = 0.0015, aOR: 1.56, 95% CI: 1.15–2.12, p = 0.0046, respectively).
Conclusions
Our findings reveal significant survivorship bias among longitudinal survey respondents, indicating that restricting analytic samples to only respondents who provide repeated assessments in longitudinal survey studies could lead to overly optimistic interpretations of mental health trends over time. Cross-sectional or planned missing data designs may provide more accurate estimates of population-level adverse mental health symptom prevalence than longitudinal surveys.
Nudges based on social norms (norm-nudges) can be compelling behavioral interventions compared with traditional interventions such as taxes and regulations, but they do not work in all circumstances. We tested two empirical norm-nudge frames in an online experiment on taking measures for flood preparedness with large samples of homeowners (N = 1805) in two European countries, to evaluate the possible interactions between norm-nudge effectiveness, individual characteristics, and intercultural differences. We contrasted these norm-nudge treatments with a control and norm-focusing treatment by asking respondents to express their beliefs about what other respondents would do before making a decision relevant to their own payoff. We find no evidence of a treatment effect, suggesting that our social norm-nudges do not affect flood preparedness in the context of a flood risk investment game.
Individuals present in lower Manhattan during the 9/11 World Trade Center (WTC) disaster suffered from significant physical and psychological trauma. Studies of longitudinal psychological distress among those exposed to trauma have been limited to relatively short durations of follow-up among smaller samples.
Methods
The current study longitudinally assessed heterogeneity in trajectories of psychological distress among WTC Health Registry enrollees – a prospective cohort health study of responders, students, employees, passersby, and residents in the affected area (N = 30 839) – throughout a 15-year period following the WTC disaster. Rescue/recovery status and exposure to traumatic events of 9/11, as well as sociodemographic factors and health status, were assessed as risk factors for trajectories of psychological distress.
Results
Five psychological distress trajectory groups were found: none-stable, low-stable, moderate-increasing, moderate-decreasing, and high-stable. Of the study sample, 78.2% were classified as belonging to the none-stable or low-stable groups. Female sex, being younger at the time of 9/11, lower education and income were associated with a higher probability of being in a greater distress trajectory group relative to the none-stable group. Greater exposure to traumatic events of 9/11 was associated with a higher probability of a greater distress trajectory, and community members (passerby, residents, and employees) were more likely to be in greater distress trajectory groups – especially in the moderate-increasing [odds ratios (OR) 2.31 (1.97–2.72)] and high-stable groups [OR 2.37 (1.81–3.09)] – compared to the none-stable group.
Conclusions
The current study illustrated the heterogeneity in psychological distress trajectories following the 9/11 WTC disaster, and identified potential avenues for intervention in future disasters.