Surface-hopping dynamics and decoherence with quantum equilibrium structure

In open quantum systems decoherence occurs through interaction of a quantum subsystem with its environment. The computation of expectation values requires a knowledge of the quantum dynamics of operators and sampling from initial states of the density matrix describing the subsystem and bath. We consider situations where the quantum evolution can be approximated by quantum-classical Liouville dynamics and examine the circumstances under which the evolution can be reduced to surface-hopping dynamics, where the evolution consists of trajectory segments evolving exclusively on single adiabatic surfaces, with probabilistic hops between these surfaces. The justification for the reduction depends on the validity of a Markovian approximation on a bath averaged memory kernel that accounts for quantum coherence in the system. We show that such a reduction is often possible when initial sampling is from either the quantum or classical bath initial distributions. If the average is taken only over the quantum dispersion that broadens the classical distribution, then such a reduction is not always possible.Comment: 11, pages, 8 figure

A mental health–informed physical activity intervention for first responders and their partners delivered using Facebook: Mixed methods pilot study

Background: First responders (eg, police, firefighters, and paramedics) are at high risk of experiencing poor mental health. Physical activity interventions can help reduce symptoms and improve mental health in this group. More research is needed to evaluate accessible, low-cost methods of delivering programs. Social media may be a potential platform for delivering group-based physical activity interventions. Objective: This study aims to examine the feasibility and acceptability of delivering a mental health–informed physical activity program for first responders and their self-nominated support partners. This study also aims to assess the feasibility of applying a novel multiple time series design and to explore the impact of the intervention on mental health symptoms, sleep quality, quality of life, and physical activity levels. Methods: We co-designed a 10-week web-based physical activity program delivered via a private Facebook group. We provided education and motivation around different topics weekly (eg, goal setting, overcoming barriers to exercise, and reducing sedentary behavior) and provided participants with a Fitbit. A multiple time series design was applied to assess psychological distress levels, with participants acting as their own control before the intervention. Results: In total, 24 participants (12 first responders and 12 nominated support partners) were recruited, and 21 (88%) completed the postassessment questionnaires. High acceptability was observed in the qualitative interviews. Exploratory analyses revealed significant reductions in psychological distress during the intervention. Preintervention and postintervention analysis showed significant improvements in quality of life (P=.001; Cohen d=0.60); total depression, anxiety, and stress scores (P=.047; Cohen d=0.35); and minutes of walking (P=.04; Cohen d=0.55). Changes in perceived social support from family (P=.07; Cohen d=0.37), friends (P=.10; Cohen d=0.38), and sleep quality (P=.28; Cohen d=0.19) were not significant. Conclusions: The results provide preliminary support for the use of social media and a multiple time series design to deliver mental health–informed physical activity interventions for first responders and their support partners. Therefore, an adequately powered trial is required

Cognitive effects of brief and ultrabrief pulse bitemporal electroconvulsive therapy: A randomised controlled proof-of-concept trial

Background Reduction of the pulse width has been reported to improve ECT outcomes with unilateral ECT (similar efficacy, fewer cognitive side effects), but has been minimally studied for bitemporal ECT. The only study comparing brief and ultrabrief pulse bitemporal ECT found reduced efficacy for bitemporal ultrabrief compared to bitemporal brief pulse stimulation. This randomised controlled trial (RCT) aimed to test if ultrabrief pulse bitemporal ECT results in fewer cognitive side effects than brief pulse bitemporal ECT, when given at doses adjusted with the aim of achieving comparable efficacy.Methods Thirty-six participants were randomly assigned to receive ultrabrief (at 3 times seizure threshold) or brief (at 1.5 times seizure threshold) pulse bitemporal ECT given 3 times a week in a double-blind, controlled proof-of-concept trial. Blinded raters assessed mood and cognitive functioning over the ECT course.Results Efficacy and cognitive outcomes did not differ significantly between the two treatment groups over the ECT course. The ultrabrief pulse group performed better on a test of visual memory assessed acutely after an ECT treatment.Conclusions This study suggests there may be a small cognitive advantage in giving bitemporal ECT with an ultrabrief pulse when dosage is increased to match the efficacy of brief pulse bitemporal ECT, but the study was underpowered to fully examine this issue. Clinical Trials Registration: www.clinicaltrials.gov, NCT00870805

The influence of personality on trajectories of distress, health and functioning in mild-to-moderately depressed adults with type 2 diabetes

Identification of mental health risk is important for optimising diabetes care in type 2 diabetes mellitus (T2DM). Personality is linked to diabetes health and may assist detection of individuals with T2DM most at risk of chronic mental health difficulties. This study examined the moderator effect of personality factors on changes in psychological distress and functioning in adults with T2DM and mild-to-moderate depressive symptoms across a 12-month period. Data were obtained from participants in a randomised controlled trial of adults with T2DM.  Participants completed measures of depression (Patient Health Questionnaire-9), anxiety (General Anxiety Disorder-7), general functioning (Work and Social Adjustment Scale), diabetes distress (Diabetes Distress Scale), and diabetes self-management (Self-Management Profile for Type 2 Diabetes) at baseline, 3-, 6- and 12-months. Glycaemic control (HbA1c) was measured at baseline, 6- and 12-months. Two hundred trial completers agreed to complete a personality inventory (Big Five Inventory). Low neuroticism was linked with reduced depression, anxiety, functional impairment and diabetes distress over the year. High extraversion was associated with decreased anxiety and functional impairment. High conscientiousness was linked to increased healthy eating. No personality trait moderated HbA1c levels. Personality screening may help identify mental health risk and guide medical carer approach in T2DM patients

The anaesthetic-ECT time interval with thiopentone—Impact on seizure quality

Background: The time between anaesthetic induction and ECT stimulus administration has been hypothesised to significantly impact ictal EEG quality. In this study, our aim was to examine the effect of the time interval between anaesthetic induction and the ECT stimulus for ictal seizure quality in ECT sessions utilising thiopentone anaesthesia. Methods: 413 EEG traces from 42 patients, collected retrospectively, were manually rated using a quantitative-qualitative structured rating scale (indices including seizure amplitude, regularity, post-ictal suppression and general seizure quality). Linear Mixed Effects Models were used to analyse the effect of the anaesthetic-ECT time interval on seizure quality indices, seizure duration and orientation scores after ECT, controlling for patient and ECT treatment factors. Results: The anaesthetic-ECT time interval had a significant impact on ictal EEG quality indices (p < 0.05), with longer times producing higher quality seizures. Seizure duration and orientation scores after ECT were not significantly influenced by the anaesthetic-ECT time interval. Age, anaesthetic dose, ECT type and ECT treatment number also had a significant impact on measures of seizure quality (p < 0.05). Limitations: The effect of ventilation technique was not explicitly measured. Only manual ratings of ictal quality were analysed. Conclusions: The time between anaesthetic induction and ECT stimulus administration has a significant impact on the ictal EEG seizure quality observed, with thiopentone anaesthetic. These results are consistent with prior findings with propofol anaesthesia, and suggest a need for routine clinical monitoring of this time interval. This variable warrants consideration when interpreting ictal EEGs, which often informs subsequent dosing decisions

Vibrational Förster transfer to hydrated protons

We have studied the influence of excess protons on the vibrational energy relaxation of the O-H and O-D stretching modes in water using femtosecond pump-probe spectroscopy. Without excess protons, we observe exponential decays with time constants of 1.7 and 4.3 ps for the bulk and anion bound O-D stretch vibrations. The addition of protons introduces a new energy relaxation pathway, which leads to an increasingly nonexponential decay of the O-D stretch vibration. This new pathway is attributed to a distance-dependent long range dipole-dipole (Förster) interaction between the O-D stretching vibration and modes associated with dissolved protons. The high efficiency of hydrated protons as receptors of vibrational energy follows from the very large absorption cross section and broad bandwidth of protons in water. For a proton concentration of 1M we find that Förster energy transfer occurs over an average distance of 4.5 Å, which corresponds to a separation of about two water molecules

Effects of polygenic risk for suicide attempt and risky behavior on brain structure in young people with familial risk of bipolar disorder

Bipolar disorder (BD) is associated with a 20–30-fold increased suicide risk compared to the general population. First-degree relatives of BD patients show inflated rates of psychopathology including suicidal behaviors. As reliable biomarkers of suicide attempts (SA) are lacking, we examined associations between suicide-related polygenic risk scores (PRSs)—a quantitative index of genomic risk—and variability in brain structures implicated in SA. Participants (n = 206; aged 12–30 years) were unrelated individuals of European ancestry and comprised three groups: 41 BD cases, 96 BD relatives (“high risk”), and 69 controls. Genotyping employed PsychArray, followed by imputation. Three PRSs were computed using genome-wide association data for SA in BD (SA-in-BD), SA in major depressive disorder (SA-in-MDD) (Mullins et al., 2019, The American Journal of Psychiatry, 176(8), 651–660), and risky behavior (Karlsson Linnér et al., 2019, Nature Genetics, 51(2), 245–257). Structural magnetic resonance imaging processing employed FreeSurfer v5.3.0. General linear models were constructed using 32 regions-of-interest identified from suicide neuroimaging literature, with false-discovery-rate correction. SA-in-MDD and SA-in-BD PRSs negatively predicted parahippocampal thickness, with the latter association modified by group membership. SA-in-BD and Risky Behavior PRSs inversely predicted rostral and caudal anterior cingulate structure, respectively, with the latter effect driven by the “high risk” group. SA-in-MDD and SA-in-BD PRSs positively predicted cuneus structure, irrespective of group. This study demonstrated associations between PRSs for suicide-related phenotypes and structural variability in brain regions implicated in SA. Future exploration of extended PRSs, in conjunction with a range of biological, phenotypic, environmental, and experiential data in high risk populations, may inform predictive models for suicidal behaviors.Australian National Health and Medical Research Council (NHMRC); Lansdowne Foundation, Paul and Jenny Reid, Good Talk, and the Keith Pettigrew Family Bequest. DNA extraction was undertaken by Genetic Repositories Australia (GRA; www.neura.edu.au/GRA), Claudio Toma is a recipient of a “Ramón y Cajal” fellowship (RYC2018-024106-I) from the Spanish MINECO. This research was undertaken with the assistance of resources from the National Computational Infrastructure (NCI), which is supported by the Australian Governmen

Recruiting to a Randomized Controlled Trial of a Web-Based Program for People With Type 2 Diabetes and Depression: Lessons Learned at the Intersection of e-Mental Health and Primary Care

Background: E-mental health (eMH) interventions are now widely available and they have the potential to revolutionize the way that health care is delivered. As most health care is currently delivered by primary care, there is enormous potential for eMH interventions to support, or in some cases substitute, services currently delivered face to face in the community setting. However, randomized trials of eMH interventions have tended to recruit participants using online recruitment methods. Consequently, it is difficult to know whether participants who are recruited online differ from those who attend primary care. Objective: This paper aimed to document the experience of recruiting to an eMH trial through primary care and compare the characteristics of participants recruited through this and other recruitment methods. Methods: Recruitment to the SpringboarD randomized controlled trial was initially focused on general practices in 2 states of Australia. Over 15 months, we employed a comprehensive approach to engaging practice staff and supporting them to recruit patients, including face-to-face site visits, regular contact via telephone and trial newsletters, and development of a Web-based patient registration portal. Nevertheless, it became apparent that these efforts would not yield the required sample size, and we therefore supplemented recruitment through national online advertising and promoted the study through existing networks. Baseline characteristics of participants recruited to the trial through general practice, online, or other sources were compared using the analysis of variance and chi square tests. Results: Between November 2015 and October 2017, 780 people enrolled in SpringboarD, of whom 740 provided information on the recruitment source. Of these, only 24 were recruited through general practice, whereas 520 were recruited online and 196 through existing networks. Key barriers to general practice recruitment included perceived mismatch between trial design and diabetes population, prioritization of acute health issues, and disruptions posed by events at the practice and community level. Participants recruited through the 3 different approaches differed in age, gender, employment status, depressive symptoms, and diabetes distress, with online participants being distinguished from those recruited through general practice or other sources. However, most differences reached only a small effect size and are unlikely to be of clinical importance. Conclusions: Time, labor, and cost-intensive efforts did not translate into successful recruitment through general practice in this instance, with barriers identified at several different levels. Online recruitment yielded more participants, who were broadly similar to those recruited via general practice

A Web-Based Cognitive Behavior Therapy Intervention to Improve Social and Occupational Functioning in Adults With Type 2 Diabetes (The SpringboarD Trial): Randomized Controlled Trial

BACKGROUND: Depressive symptoms are common in people with type 2 diabetes mellitus (T2DM). Effective depression treatments exist; however, access to psychological support is characteristically low. Web-based cognitive behavioral therapy (CBT) is accessible, nonstigmatizing, and may help address substantial personal and public health impact of comorbid T2DM and depression. OBJECTIVE: The aim of this study was to evaluate the Web-based CBT program, myCompass, for improving social and occupational functioning in adults with T2DM and mild-to-moderate depressive symptoms. myCompass is a fully automated, self-guided public health treatment program for common mental health problems. The impact of treatment on depressive symptoms, diabetes-related distress, anxiety symptoms, and self-care behavior was also examined. METHODS: Participants with T2DM and mild-to-moderate depressive symptoms (N=780) were recruited online via Google and Facebook advertisements targeting adults with T2DM and via community and general practice settings. Screening, consent, and self-report scales were all self-administered online. Participants were randomized using double-blind computerized block randomization to either myCompass (n=391) for 8 weeks plus a 4-week tailing-off period or an active placebo intervention (n=379). At baseline and postintervention (3 months), participants completed the Work and Social Adjustment Scale, the primary outcome measure. Secondary outcome measures included the Patient Health Questionnaire-9 item, Diabetes Distress Scale, Generalized Anxiety Disorder Questionnaire-7 item, and items from the Self-Management Profile for Type 2 Diabetes. RESULTS: myCompass users logged in an average of 6 times and completed an average of .29 modules. Healthy Lifestyles users logged in an average of 4 times and completed an average of 1.37 modules. At baseline, mean scores on several outcome measures, including the primary outcome of work and social functioning, were near to the normal range, despite an extensive recruitment process. Approximately 61.6% (473/780) of participants completed the postintervention assessment. Intention-to-treat analyses revealed improvement in functioning, depression, anxiety, diabetes distress, and healthy eating over time in both groups. Except for blood glucose monitoring and medication adherence, there were no specific between-group effects. Follow-up analyses suggested the outcomes did not depend on age, morbidity, or treatment engagement. CONCLUSIONS: Improvement in social and occupational functioning and the secondary outcomes was generally no greater for myCompass users than for users of the control program at 3 months postintervention. These findings should be interpreted in light of near-normal mean baseline scores on several variables, the self-selected study sample, and sample attrition. Further attention to factors influencing uptake and engagement with mental health treatments by people with T2DM, and the impact of illness comorbidity on patient conceptualization and experience of mental health symptoms, is essential to reduce the burden of T2DM. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12615000931572; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=368109&isReview=true (Archived by WebCite at http://www.webcitation.org/7850eg8pi)