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Copper-doped zinc sulfide (ZnS:Cu) exhibits down-conversion luminescence in the UV, visible, and IR regions of the electromagnetic spectrum; the visible red, green, and blue emission is referred to as R-Cu, G-Cu, and B-Cu, respectively. The sub-bandgap emission arises from optical transitions between localized electronic states created by point defects, making ZnS:Cu a prolific phosphor material and an intriguing candidate material for quantum information science, where point defects excel as single-photon sources and spin qubits. Colloidal nanocrystals (NCs) of ZnS:Cu are particularly interesting as hosts for the creation, isolation, and measurement of quantum defects, since their size, composition, and surface chemistry can be precisely tailored for bio-sensing and opto-electronic applications. Here, we present a method for synthesizing colloidal ZnS:Cu NCs that emit primarily R-Cu, which has been proposed to arise from the Cu$_{Zn}$-V$_S$ complex, an impurity-vacancy point defect structure analogous to well-known quantum defects in other materials that produce favorable optical and spin dynamics. First principles calculations confirm the thermodynamic stability and electronic structure of Cu$_{Zn}$-V$_S$. Temperature- and time-dependent optical properties of ZnS:Cu NCs show blueshifting luminescence and an anomalous plateau in the intensity dependence as temperature is increased from 19 K to 290 K, for which we propose an empirical dynamical model based on thermally-activated coupling between two manifolds of states inside the ZnS bandgap. Understanding of R-Cu emission dynamics, combined with a controlled synthesis method for obtaining R-Cu centers in colloidal NC hosts, will greatly facilitate the development of Cu$_{Zn}$-V$_S$ and related complexes as quantum point defects in ZnS., Comment: 31 pages, 19 figures

Atomically thin MoS2 nanosheets are of interest due to unique electronic, optical, and catalytic properties that are absent in the bulk material. Methods to prepare nanosheets from bulk material th...

Colloidal quantum dots (QDs) are nanoscale semiconductor crystals with surface ligands that enable their dispersion in solvents. Quantum confinement effects facilitate wave function engineering to sculpt the spatial distribution of charge and spin states and thus the energy and dynamics of QD optical transitions. Colloidal QDs can be integrated in devices using solution-based assembly methods to position single QDs and to create ordered QD arrays. Here, we describe the synthesis, assembly, and photophysical properties of colloidal QDs that have captured scientific imagination and have been harnessed in optical applications. We focus especially on the current understanding of their quantum coherent effects and opportunities to exploit QDs as platforms for quantum information science. Freedom in QD design to isolate and control the quantum mechanical properties of charge, spin, and light presents various approaches to create systems with robust, addressable quantum states. We consider the attributes of QDs for optically addressable qubits in emerging quantum computation, sensing, simulation, and communication technologies, e.g., as robust sources of indistinguishable, single photons that can be integrated into photonic structures to amplify, direct, and tune their emission or as hosts for isolated, coherent spin states that can be coupled to light or to other spins in QD arrays.

The COVID-19 pandemic offers both challenges and opportunities for those who provide and receive psychological services. For training clinics tasked with educating the next generation of health service psychologists, providing vital mental health care to the community, and conducting clinical research, the pandemic offers an opportunity to consider how best to fulfill these crucial missions during a time of global uncertainty. The present paper reviews the recent, rapid move to telepsychology among North American university training clinics in response to the COVID-19 pandemic and offers relevant suggestions for mental health service providers rapidly transitioning to telepsychology moving forward. Data summarizing the response of university training clinics in health service psychology in the United States and Canada to physical distancing guidelines are presented, and considerations regarding best practices in service delivery and supervision via telepsychology are provided. While the present data focus on North American training clinics, the suggestions offered are relevant to any clinic tasked with providing high quality services and training mental health providers via telepsychology, particularly during the COVID-19 pandemic. Given the growing emphasis within health service psychology on increasing access to mental health services via telepsychology prior to the pandemic, as well as the benefits to psychology trainees in gaining competence in this valuable form of service delivery, this paper aims to provide timely guidance around the benefits, risks, and practical considerations regarding the maintenance of effective clinical care in training settings when rapidly implementing telepsychology.

Objectives The present study sought to examine the association between maternal depressive symptoms and characteristics of offspring physical health, including health status, health behaviors, and healthcare utilization, among low-income families. Maternal engagement was explored as a mediator of observed effects. Methods Cross-sectional survey data from a community sample of 4589 low-income women and their preschool-age children participating in the WIC program in Los Angeles County were analyzed using logistic, Poisson, and zero-inflated negative binomial regression. Mediation was tested via conditional process analyses. Results After controlling for the effects of demographic characteristics including maternal health insurance coverage, employment status, education, and preferred language, children of depressed women (N = 1025) were significantly more likely than children of non-depressed women (N = 3564) to receive a "poor" or "fair" maternal rating of general health (OR 2.34), eat fewer vegetables (IRR: 0.94) more sweets (IRR: 1.20) and sugary drinks daily (IRR: 1.32), and consume fast food more often (OR 1.21). These children were also less likely to have health insurance (OR 1.59) and more likely to receive medical care from a public medical clinic or hospital emergency room (OR 1.30). Reduced maternal engagement partially mediated associations between maternal depressive symptoms and several child health outcomes including poor diet, health insurance coverage, and use of public medical services. Conclusions for Practice Maternal depressive symptoms are associated with poor health among preschool-age children in low-income families. Prevention, screening, and treatment efforts aimed at reducing the prevalence of maternal depression may positively affect young children's health.

We have developed highly flexible imaging bands that incorporate light source and detectors for assessing joint diseases, such as rheumatoid arthritis (RA). The resulting low-cost imaging system supports high-fidelity data acquisition, which allows for dynamic optical measurements in the field of diffuse optical tomography (DOT).

Objective We explored whether patients with varied levels of baseline deficits in compensatory skills and self-understanding had different outcomes across cognitive and dynamic therapies.

The goal of this investigation was to explore changes in psychotherapy utilization for patients with major depressive disorder (MDD) treated in community mental health agencies across two cohorts. We used a Medicaid claims database including approximately 300,000 public sector clients. Although the use of psychotherapy alone showed a small decrease, there was a large increase in the use of combined medication and psychotherapy as a treatment for MDD. Race was a significant predictor of both treatment type received and length of treatment. African American consumers were more likely to receive psychotherapy alone than combined treatment and attended significantly fewer psychotherapy sessions.

Computerized administration of mental health-related questionnaires has become relatively common, but little research has explored this mode of assessment in "real-world" settings. In the current study, 200 consumers at a community mental health center completed the BASIS-24 via handheld computer as well as paper and pen. Scores on the computerized BASIS-24 were compared with scores on the paper BASIS-24. Consumers also completed a questionnaire which assessed their level of satisfaction with the computerized BASIS-24. Results indicated that the BASIS-24 administered via handheld computer was highly correlated with pen and paper administration of the measure and was generally acceptable to consumers. Administration of the BASIS-24 via handheld computer may allow for efficient and sustainable outcomes assessment, adaptable research infrastructure, and maximization of clinical impact in community mental health agencies.

Puberty is accompanied by numerous psychological and interpersonal challenges, including a dramatic rise in the prevalence of depression among girls. Pubertal timing has been identified as a potent predictor of depressive symptoms among females, but less is known about other features of puberty. The present study sought to address this gap in the literature by examining the effect of pubertal synchrony, the degree to which morphological indicators of puberty develop concurrently, on depressive symptoms in adolescence and emerging adulthood in a longitudinal sample. Among 355 female participants, asynchronous development at age 13 was associated with increased depressive symptoms at age 20, but not age 15. Additional analyses indicated that pubertal timing moderated the association between synchrony and depressive symptoms at age 20, such that girls who exhibited asynchronous development had the highest levels of depressive symptoms when they matured later than peers. Results provide initial empirical support for the role of pubertal synchrony in the development of depression among females and are discussed with regard to the biopsychosocial processes that may connect features of puberty with the long-term development of psychopathology.

Chronic stress refers to the perceived and actual negative life conditions that affect a person on a daily or continuing basis, and is found to predict a wide array of debilitating emotional and behavioral states; physiological and medical changes;and neurobiological changes in development, cognition, memory, and information processing. Measures of chronic stress have been developed to cover both perceived and actual experiences, primarily focused on specific domains (e.g., financial concerns, marital or caregiving relationships, discrimination), or on general experiences across multiple roles affecting daily life (e.g., work, marriage, parenting, health).Thisentry describes more commonly used specific or general measures of chronic stress, and discusses psychometric properties of diverse questionnaire and interview assessments.Further study is needed on improving assessment methods, the nature of the content and aspects of chronic stress that are particularly harmful, and biological mechanisms associated with exposure to chronic stress. Keywords: measurement in psychology; psychology of stress; chronic strain; chronic stress; ongoing difficulties; perceived stress; stress

Maternal depression serves as a potent source of stress among offspring, greatly enhancing the risk of numerous adverse outcomes including youth depression. Several factors moderate the transmission of depression from mothers to offspring. However, the role of genetic characteristics in this process merits further exploration. Consistent with an interpersonal perspective on depression, the present study focused on a genetic polymorphism that has been shown to be relevant to social functioning, the rs53576 polymorphism of the oxytocin receptor gene (OXTR). In a community sample of 441 youth, OXTR genotype moderated the association between maternal depression in early childhood and youth depressive symptoms in adolescence, such that youth possessing at least one A allele of OXTR who also had a history of maternal depression exhibited the highest levels of depressive symptoms at age 15. In order to explore possible interpersonal mediators of this effect, conditional process analyses examined the role of youth social functioning in adolescence. Results suggest that OXTR genotype may partially account for the transmission of maternal depression to youth and support the role of dysfunctional social processes as a mechanism through which OXTR influences the development of depressive symptoms.

We assessed the impact of free on-site influenza vaccination on childcare staff vaccination prevalence using 2 before-and-after studies. Vaccination was offered during the 2003-2004 and 2006-2007 influenza seasons. Staff vaccination prevalence was higher in each intervention season compared to the prior, nonintervention season. No baseline characteristics were associated with receipt of vaccination.