Patterns in random walks and Brownian motion

We ask if it is possible to find some particular continuous paths of unit length in linear Brownian motion. Beginning with a discrete version of the problem, we derive the asymptotics of the expected waiting time for several interesting patterns. These suggest corresponding results on the existence/non-existence of continuous paths embedded in Brownian motion. With further effort we are able to prove some of these existence and non-existence results by various stochastic analysis arguments. A list of open problems is presented.Comment: 31 pages, 4 figures. This paper is published at http://link.springer.com/chapter/10.1007/978-3-319-18585-9_

Genome-wide association study identifies 30 Loci Associated with Bipolar Disorder

This paper is dedicated to the memory of Psychiatric Genomics Consortium (PGC) founding member and Bipolar disorder working group co-chair Pamela Sklar. We thank the participants who donated their time, experiences and DNA to this research, and to the clinical and scientific teams that worked with them. We are deeply indebted to the investigators who comprise the PGC. The views expressed are those of the authors and not necessarily those of any funding or regulatory body. Analyses were carried out on the NL Genetic Cluster Computer (http://www.geneticcluster.org ) hosted by SURFsara, and the Mount Sinai high performance computing cluster (http://hpc.mssm.edu).Bipolar disorder is a highly heritable psychiatric disorder. We performed a genome-wide association study including 20,352 cases and 31,358 controls of European descent, with follow-up analysis of 822 variants with P<1x10-4 in an additional 9,412 cases and 137,760 controls. Eight of the 19 variants that were genome-wide significant (GWS, p < 5x10-8) in the discovery GWAS were not GWS in the combined analysis, consistent with small effect sizes and limited power but also with genetic heterogeneity. In the combined analysis 30 loci were GWS including 20 novel loci. The significant loci contain genes encoding ion channels, neurotransmitter transporters and synaptic components. Pathway analysis revealed nine significantly enriched gene-sets including regulation of insulin secretion and endocannabinoid signaling. BDI is strongly genetically correlated with schizophrenia, driven by psychosis, whereas BDII is more strongly correlated with major depressive disorder. These findings address key clinical questions and provide potential new biological mechanisms for BD.This work was funded in part by the Brain and Behavior Research Foundation, Stanley Medical Research Institute, University of Michigan, Pritzker Neuropsychiatric Disorders Research Fund L.L.C., Marriot Foundation and the Mayo Clinic Center for Individualized Medicine, the NIMH Intramural Research Program; Canadian Institutes of Health Research; the UK Maudsley NHS Foundation Trust, NIHR, NRS, MRC, Wellcome Trust; European Research Council; German Ministry for Education and Research, German Research Foundation IZKF of Münster, Deutsche Forschungsgemeinschaft, ImmunoSensation, the Dr. Lisa-Oehler Foundation, University of Bonn; the Swiss National Science Foundation; French Foundation FondaMental and ANR; Spanish Ministerio de Economía, CIBERSAM, Industria y Competitividad, European Regional Development Fund (ERDF), Generalitat de Catalunya, EU Horizon 2020 Research and Innovation Programme; BBMRI-NL; South-East Norway Regional Health Authority and Mrs. Throne-Holst; Swedish Research Council, Stockholm County Council, Söderström Foundation; Lundbeck Foundation, Aarhus University; Australia NHMRC, NSW Ministry of Health, Janette M O'Neil and Betty C Lynch

The Physics of Star Cluster Formation and Evolution

© 2020 Springer-Verlag. The final publication is available at Springer via https://doi.org/10.1007/s11214-020-00689-4.Star clusters form in dense, hierarchically collapsing gas clouds. Bulk kinetic energy is transformed to turbulence with stars forming from cores fed by filaments. In the most compact regions, stellar feedback is least effective in removing the gas and stars may form very efficiently. These are also the regions where, in high-mass clusters, ejecta from some kind of high-mass stars are effectively captured during the formation phase of some of the low mass stars and effectively channeled into the latter to form multiple populations. Star formation epochs in star clusters are generally set by gas flows that determine the abundance of gas in the cluster. We argue that there is likely only one star formation epoch after which clusters remain essentially clear of gas by cluster winds. Collisional dynamics is important in this phase leading to core collapse, expansion and eventual dispersion of every cluster. We review recent developments in the field with a focus on theoretical work.Peer reviewe

Investigating rare pathogenic/likely pathogenic exonic variation in bipolar disorder

Bipolar disorder (BD) is a serious mental illness with substantial common variant heritability. However, the role of rare coding variation in BD is not well established. We examined the protein-coding (exonic) sequences of 3,987 unrelated individuals with BD and 5,322 controls of predominantly European ancestry across four cohorts from the Bipolar Sequencing Consortium (BSC). We assessed the burden of rare, protein-altering, single nucleotide variants classified as pathogenic or likely pathogenic (P-LP) both exome-wide and within several groups of genes with phenotypic or biologic plausibility in BD. While we observed an increased burden of rare coding P-LP variants within 165 genes identified as BD GWAS regions in 3,987 BD cases (meta-analysis OR = 1.9, 95% CI = 1.3–2.8, one-sided p = 6.0 × 10−4), this enrichment did not replicate in an additional 9,929 BD cases and 14,018 controls (OR = 0.9, one-side p = 0.70). Although BD shares common variant heritability with schizophrenia, in the BSC sample we did not observe a significant enrichment of P-LP variants in SCZ GWAS genes, in two classes of neuronal synaptic genes (RBFOX2 and FMRP) associated with SCZ or in loss-of-function intolerant genes. In this study, the largest analysis of exonic variation in BD, individuals with BD do not carry a replicable enrichment of rare P-LP variants across the exome or in any of several groups of genes with biologic plausibility. Moreover, despite a strong shared susceptibility between BD and SCZ through common genetic variation, we do not observe an association between BD risk and rare P-LP coding variants in genes known to modulate risk for SCZ

Biomass offsets little or none of permafrost carbon release from soils, streams, and wildfire: an expert assessment

As the permafrost region warms, its large organic carbon pool will be increasingly vulnerable to decomposition, combustion, and hydrologic export. Models predict that some portion of this release will be offset by increased production of Arctic and boreal biomass; however, the lack of robust estimates of net carbon balance increases the risk of further overshooting international emissions targets. Precise empirical or model-based assessments of the critical factors driving carbon balance are unlikely in the near future, so to address this gap, we present estimates from 98 permafrost-region experts of the response of biomass, wildfire, and hydrologic carbon flux to climate change. Results suggest that contrary to model projections, total permafrost-region biomass could decrease due to water stress and disturbance, factors that are not adequately incorporated in current models. Assessments indicate that end-of-the-century organic carbon release from Arctic rivers and collapsing coastlines could increase by 75% while carbon loss via burning could increase four-fold. Experts identified water balance, shifts in vegetation community, and permafrost degradation as the key sources of uncertainty in predicting future system response. In combination with previous findings, results suggest the permafrost region will become a carbon source to the atmosphere by 2100 regardless of warming scenario but that 65%–85% of permafrost carbon release can still be avoided if human emissions are actively reduced

Dignity therapy online: Piloting an online psychosocial intervention for people with terminal illness

Objective Dignity therapy is a life review intervention shown to reduce distress and enhance the quality of life for people with a terminal illness and their families. Dignity therapy is not widely used in clinical practice because it is time and cost prohibitive. This pilot study examined the feasibility and acceptability of dignity therapy delivered through therapist-supported web-based delivery to reduce costs, increase time efficiency, and promote access to treatment. Methods This study employed a one-group pre-test post-test design to pilot methods. Australian adults diagnosed with a terminal illness with a prognosis of six months or less were recruited for the study. The primary outcome measure was a Participant Feedback Questionnaire used in previous face-to-face dignity therapy studies. Data regarding therapist time and details about final documents were recorded. Results Six people were recruited; four chose to complete the intervention via video conference and two chose email. Participants reported high levels of acceptability and efficacy comparable to face-to-face delivery; meanwhile therapist time was about 40% less and legacy documents were longer. Participants described dignity therapy online as convenient, but technological issues may create challenges. Conclusions Online delivery of dignity therapy is feasible and acceptable, reduces therapist time and clinical cost, and appears to reach people who would not otherwise receive the therapy. Dignity therapy via email may have the greatest potential to reduce time and cost barriers. This pilot study demonstrates a need for further research to determine the full benefits of online delivery of dignity therapy

The perceived effects of emotional labor in psychologists providing individual psychotherapy

Existing literature examining burnout in psychotherapists has not adequately considered the contributing role of emotional labor. Similarly, emotional labor research has not sufficiently explored how this construct operates in the context of psychologists who provide individual psychotherapy. To address these existing gaps in the literature, thematic analysis was conducted on interviews with 24 psychologists who provide individual psychotherapy to determine the perceived consequences of emotional labor identified by the participants. Participants discussed personal growth, feeling depleted and exhausted, and craving space free from people and work-related emotion as consequences of emotion management in the context of providing individual psychotherapy. The findings suggest that emotional labor can exert positive, negative, and neutral effects on psychologists providing psychotherapy and is worthy of attention as a variable in efforts to promote positive well-being. In the occupational group of psychologists providing individual psychotherapy, performing emotional labor can lead to personal growth, emotional exhaustion, and a need to distance oneself from work-related emotion. (PsycInfo Database Record (c) 2020 APA, all rights reserved

Development and initial test of the self-report grief and bereavement assessment

Implementing evidence-based and cost-effective bereavement care is a challenge. A self-report measure could assist to identify caregivers at-risk of prolonged grief. We developed a new measure via five steps: identification of risk and protective factors for prolonged grief, item generation, consultation with an expert panel (n = 8), review by the academic team and expert panel, and a pilot test with family caregivers (n = 19) from three palliative care services. The Grief and Bereavement Assessment is a brief self-report measure that is theoretically and empirically grounded, acceptable to caregivers, feasible for use in palliative care, and requires psychometric validation

Family carers' experiences of receiving the news of a Motor Neurone Disease: a national survey

Family carers have a central role in the care and support of people with MND and face the challenges of the disease from diagnosis to progression and the multiple losses of MND, but their support needs are often neglected. This study aimed to investigate the experiences of family carers at the time of diagnosis and their satisfaction with receiving the news. An anonymous postal survey was facilitated by all MND Associations in Australia (2014) and 190 family carers completed the questionnaire. The questions centred on the SPIKES protocol for communicating bad news. Two-thirds of family carers rated the skills of their neurologists as above average and were satisfied with the delivery of the diagnosis, in terms of having a significantly longer consultation time, the neurologist being warm and caring, satisfaction with the amount and content of information they received and relevant supports, and a plan for following up support. Conversely those who rated the neurologist's skills as below average commented on the difficulties they encountered and the long term emotional stress engendered by poor communication. The study emphasises previous research that suggested that neurologists may require education and training in communicating the diagnosis and this should include family carers as a vital member in MND care