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Racial and ethnic groups in the USA differ in the prevalence of posttraumatic stress disorder (PTSD). Recent research however has not observed consistent racial/ethnic differences in posttraumatic stress in the early aftermath of trauma, suggesting that such differences in chronic PTSD rates may be related to differences in recovery over time.
As part of the multisite, longitudinal AURORA study, we investigated racial/ethnic differences in PTSD and related outcomes within 3 months after trauma. Participants (n = 930) were recruited from emergency departments across the USA and provided periodic (2 weeks, 8 weeks, and 3 months after trauma) self-report assessments of PTSD, depression, dissociation, anxiety, and resilience. Linear models were completed to investigate racial/ethnic differences in posttraumatic dysfunction with subsequent follow-up models assessing potential effects of prior life stressors.
Racial/ethnic groups did not differ in symptoms over time; however, Black participants showed reduced posttraumatic depression and anxiety symptoms overall compared to Hispanic participants and White participants. Racial/ethnic differences were not attenuated after accounting for differences in sociodemographic factors. However, racial/ethnic differences in depression and anxiety were no longer significant after accounting for greater prior trauma exposure and childhood emotional abuse in White participants.
The present findings suggest prior differences in previous trauma exposure partially mediate the observed racial/ethnic differences in posttraumatic depression and anxiety symptoms following a recent trauma. Our findings further demonstrate that racial/ethnic groups show similar rates of symptom recovery over time. Future work utilizing longer time-scale data is needed to elucidate potential racial/ethnic differences in long-term symptom trajectories.
Physical distancing among healthcare workers (HCWs) is an essential strategy in preventing HCW-to-HCWs transmission of severe acute respiratory coronavirus virus 2 (SARS-CoV-2).
To understand barriers to physical distancing among HCWs on an inpatient unit and identify strategies for improvement.
Qualitative study including observations and semistructured interviews conducted over 3 months.
A non–COVID-19 adult general medical unit in an academic tertiary-care hospital.
HCWs based on the unit.
We performed a qualitative study in which we (1) observed HCW activities and proximity to each other on the unit during weekday shifts July–October 2020 and (2) conducted semi-structured interviews of HCWs to understand their experiences with and perspectives of physical distancing in the hospital. Qualitative data were coded based on a human-factors engineering model.
We completed 25 hours of observations and 20 HCW interviews. High-risk interactions often occurred during handoffs of care at shift changes and patient rounds, when HCWs gathered regularly in close proximity for at least 15 minutes. Identified barriers included spacing and availability of computers, the need to communicate confidential patient information, and the desire to maintain relationships at work.
Physical distancing can be improved in hospitals by restructuring computer workstations, work rooms, and break rooms; applying visible cognitive aids; adapting shift times; and supporting rounds and meetings with virtual conferencing. Additional strategies to promote staff adherence to physical distancing include rewarding positive behaviors, having peer leaders model physical distancing, and encouraging additional safe avenues for social connection at a safe distance.
The aim of this study was to detect longitudinal differences in white matter brain structures in adults with schizophrenia compared to healthy controls.
Twenty adult patients with multi-episode schizophrenia under stable antipsychotic medication and twenty-two age- and sex-matched healthy subjects were included in the study. Diffusion Tensor Imaging (DTI) was applied at baseline (t1), after 6weeks (t2) and after 3months (t3) and data processing was done with tract-based spatial statistics (p<0.05, corrected). Two subjects in the schizophrenic sample dropped out at t2 and one healthy subject at t3. Clinical and neuropsychological variables were measured and correlated with the most significant DTI findings.
Compared with healthy age- and sex-matched controls schizophrenic patients showed widespread decreases in mean fractional anisotropy values (p<0.05, corrected). The most obvious FA decrease in the long-term was found in the anterior part of the corpus callosum (p<0.005, corrected), the left temporal lobe (p<0.004, corr.) and the mid-cingulate gyrus bilateral (p<0.004, corr.). Correlations to demographic variables, clinical rating scales (PANSS, CGI and GAF), verbal learning and memory and working memory will be presented.
Magnetic resonance imaging was able to detect altered structural connectivity in patients with multi-episode schizophrenia in a longitudinal design.
Patients with schizophrenia might benefit from exercise via multiple ways. It can be assumed that positive effects observed in healthy people counteract different pathological dimensions of schizophrenia or add to a better compensation. E.g. exercise may serve as a coping strategy, produces changes in brain structure and function and is already known to improve mood and cardiovascular health. First studies have shown beneficial effects of exercise in schizophrenia. These studies feature a multitude of exercise types and diagnostic tests and also lay emphasis on different research questions.
From the diverse information of the studies, heterogenic character conclusions for future therapy and research can be derived. From the point of view of sports science, feasibility and effectiveness of endurance training will be discussed on the basis of current literature and results from our own research. In a controlled trial 22 patients with schizophrenia participated in 12 weeks of endurance training using bicycle ergometers resulting, e. g., in improvements of endurance capacity and functioning. A special focus was laid on analyzing the differences between the adaptations of patients and healthy controls to test the transferability of methods and effects of endurance training. The exercise intervention was feasible and effective for both healthy controls and patients but some interesting differences could be found.
Additionally, ideas and special circumstances regarding the implementation of endurance training in clinical settings or for outpatients will be considered. From the current knowledge it can be concluded, that the implementation of endurance training in multimodal therapy strategies can be recommended to promote recovery.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Biological tissues have complex, three-dimensional (3D) organizations of cells and matrix factors that provide the architecture necessary to meet morphogenic and functional demands. Disordered cell alignment is associated with congenital heart disease, cardiomyopathy, and neurodegenerative diseases and repairing or replacing these tissues using engineered constructs may improve regenerative capacity. However, optimizing cell alignment within engineered tissues requires quantitative 3D data on cell orientations and both efficient and validated processing algorithms. We developed an automated method to measure local 3D orientations based on structure tensor analysis and incorporated an adaptive subregion size to account for multiple scales. Our method calculates the statistical concentration parameter, κ, to quantify alignment, as well as the traditional orientational order parameter. We validated our method using synthetic images and accurately measured principal axis and concentration. We then applied our method to confocal stacks of cleared, whole-mount engineered cardiac tissues generated from human-induced pluripotent stem cells or embryonic chick cardiac cells and quantified cardiomyocyte alignment. We found significant differences in alignment based on cellular composition and tissue geometry. These results from our synthetic images and confocal data demonstrate the efficiency and accuracy of our method to measure alignment in 3D tissues.
One of the major science goals of the SkyMapper survey of the Southern Hemisphere sky is the determination of the shape and extent of the halo of the Galaxy. In this paper, we quantify the likely efficiency and completeness of the survey as regards the detection of RR Lyrae variable stars, which are excellent tracers of the halo stellar population. We have accomplished this via observations of the RR Lyrae-rich globular cluster NGC 3201. We find that for single-epoch uvgri observations followed by two further epochs of g, r imaging, as per the intended three-epoch survey strategy, we recover known RR Lyraes with a completeness exceeding 90%. We also investigate boundaries in the gravity-sensitive single-epoch two-colour diagram that yield high completeness and high efficiency (i.e., minimal contamination by non-RR Lyraes) and the general usefulness of this diagram in separating populations.
This paper presents the design and science goals for the SkyMapper telescope. SkyMapper is a 1.3-m telescope featuring a 5.7-square-degree field-of-view Cassegrain imager commissioned for the Australian National University's Research School of Astronomy and Astrophysics. It is located at Siding Spring Observatory, Coonabarabran, NSW, Australia and will see first light in late 2007.
The imager possesses 16 384 × 16 384 0.5-arcsec pixels. The primary scientific goal of the facility is to perform the Southern Sky Survey, a six-colour and multi-epoch (four-hour, one-day, one-week, one-month and one-year sampling) photometric survey of the southerly 2π sr to g ∼23 mag. The survey will provide photometry to better than 3% global accuracy and astrometry to better than 50 milliarcsec. Data will be supplied to the community as part of the Virtual Observatory effort. The survey will take five years to complete.
It is well established that the presence of prominent anxiety within depressive episodes portends poorer outcomes. Important questions remain as to which anxiety features are important to outcome and how sustained their prognostic effects are over time.
To examine the relative prognostic importance of specific anxiety features and to determine whether their effects persist over decades and apply to both unipolar and bipolar conditions.
Participants with unipolar (n = 476) or bipolar (n = 335) depressive disorders were intensively followed for a mean of 16.7 years (s.d. = 8.5).
The number and severity of anxiety symptoms, but not the presence of pre-existing anxiety disorders, showed a robust and continuous relationship to the subsequent time spent in depressive episodes in both unipolar and bipolar depressive disorder. The strength of this relationship changed little over five successive 5-year periods.
The severity of current anxiety symptoms within depressive episodes correlates strongly with the persistence of subsequent depressive symptoms and this relationship is stable over decades.
Magneto-optical garnet based optical circulator was designed and fabricated with wafer-scale technology. Modeling and simulation strategy is established for the optimization of a new design of circulator based on ring cavity. Wafer-scale technological process is developed and demonstrated allowing fabrication of the optimized BIG/GGG buried ring circulator.
Suicide is a leading cause of death and has been strongly associated with affective disorders. The influence of affective disorder polarity on subsequent suicide attempts or completions and any differential effect of suicide risk factors by polarity were assessed in a prospective cohort.
Participants with major affective disorders in the National Institute of Mental Health (NIMH) Collaborative Depression Study (CDS) were followed prospectively for up to 25 years. A total of 909 participants meeting prospective diagnostic criteria for major depressive and bipolar disorders were followed through 4204 mood cycles. Suicidal behavior was defined as suicide attempts or completions. Mixed-effects, grouped-time survival analysis assessed risk of suicidal behavior and differential effects of risk factors for suicidal behavior by polarity. In addition to polarity, the main effects of age, gender, hopelessness, married status, prior suicide attempts and active substance abuse were modeled, with mood cycle as the unit of analysis.
After controlling for age of onset, there were no differences in prior suicide attempts by polarity although bipolar participants had more prior severe attempts. During follow-up, 40 cycles ended in suicide and 384 cycles contained at least one suicide attempt. Age, hopelessness and active substance abuse but not polarity predicted suicidal behavior. The effects of risk factors did not differ by polarity.
Bipolarity does not independently influence risk of suicidal behavior or alter the influence of well-established suicide risk factors within affective disorders. Suicide risk assessment strategies may continue to appraise these common risk factors without regard to mood polarity.
We present the first results from our next-generation microlensing survey, the SuperMACHO project. We are using the CTIO 4m Blanco telescope and the MOSAIC imager to carry out a search for microlensing toward the Large Magellanic Cloud (LMC). We plan to ascertain the nature of the population responsible for the excess microlensing rate seen by the MACHO project. Our observing strategy is optimized to measure the differential microlensing rate across the face of the LMC. We find this derivative to be relatively insensitive to the details of the LMC's internal structure but a strong discriminant between Galactic halo and LMC self lensing. In December 2003 we completed our third year of survey operations. 2003 also marked the first year of real-time microlensing alerts and photometric and spectroscopic followup. We have extracted several dozen microlensing candidates, and we present some preliminary light curves and related information. Similar to the MACHO project, we find SNe behind the LMC to be a significant contaminant - this background has not been completely removed from our current single-color candidate sample. Our follow-up strategy is optimized to discriminate between SNe and true microlensing.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html
For most of the last century, researchers have searched for a muscle contraction-induced factor that mediates some of the exercise effects in other tissues such as the liver and the adipose tissue. It has been called the ‘work stimulus’, the ‘work factor’ or the ‘exercise factor’. In the search for such a factor, a cytokine, IL-6, was found to be produced by contracting muscles and released into the blood. It has been demonstrated that IL-6 has many biological roles such as: (1) induction of lipolysis; (2) suppression of TNF production; (3) stimulation of cortisol production. The IL-6 gene is rapidly activated during exercise, and the activation of this gene is further enhanced when muscle glycogen content is low. In addition, carbohydrate supplementation during exercise has been shown to inhibit the release of IL-6 from contracting muscle. Thus, it is suggested that muscle-derived IL-6 fulfils the criteria of an exercise factor and that such classes of cytokines could be termed ‘myokines’.
Background. We tested the hypotheses that the addition of medication to psychotherapy enhances participation in the latter by: (1) speeding the acquisition of the psychotherapy's targeted skill; and (2) facilitating higher skill level acquisition.
Method. Participants were 431 chronically depressed patients who received Cognitive Behavioral Analysis System of Psychotherapy (CBASP), alone (N=214) or in combination with nefazodone (N=217), as part of a randomized chronic depression study (Keller et al. 2000). CBASP, developed specifically to treat chronic depression, uses a specific procedure, ‘situational analysis’ to help patients engage in more effective goal-oriented interpersonal behaviours. At the end of each session, therapists rated patients on their performance of situational analysis. Outcome on depressive symptoms was assessed with the 24-item Hamilton Rating Scale for Depression.
Results. Although reductions in depression were significantly greater in combined treatment compared to CBASP alone, there were no between-group differences in either the rate of skill acquisition or overall skill level at the end of treatment. Proficiency in the use of the main skill taught in psychotherapy at treatment midpoint predicted outcome independently of medication status and of baseline depressive severity.
Conclusions. Effective participation in CBASP, as reflected by proficiency in the compensatory skill taught in psychotherapy, is not enhanced by the addition of medication and does not mediate the between-group difference in depression outcome.
The hydrological ice-sheet basin draining into the Tasersiaq lake, West Greenland (66°13’ N, 50°30’W), was delineated, first using standard digital elevation models (DEMs) for ice-sheet surface and bedrock, and subsequently using a new high-resolution dataset, with a surface DEM derived from repeat-track interferometric synthetic aperture radar (SAR) and a bedrock topography derived from an airborne 60 MHz ice-penetrating radar. The extent of the delineation was calculated from a water-pressure potential as a function of the ice-sheet surface and bedrock elevations and a hydraulic factor k describing the relative importance of the potential of the ice overburden pressure compared to the bedrock topography. Themeltwater run-off for the basin delineations was modelled with an energy-balance model calibrated with observed ice-sheet ablation and compared to a 25 year time series of measured basin run-off. The standard DEMs were found to be inadequate for delineation purposes, whereas delineations from high-resolution data were found to be very sensitive to changes in k in a non-linear way, causing a factor 5 change of basin area, corresponding to a doubling of the modelled runoff. The 50% standard deviation of the measured basin run-off could thus be explained by small year-to-year variations of the k-factor.
An AlxGa1−xN/GaN two-dimensional electron gas structure with x = 0.13 deposited by molecular beam epitaxy on a GaN layer grown by organometallic vapor phase epitaxy on a sapphire substrate was characterized. Hall effect measurements gave a sheet electron concentration of 5.1×1012 cm−2 and a mobility of 1.9 × 104 cm2/Vs at 10 K. Mobility spectrum analysis showed single-carrier transport and negligible parallel conduction at low temperatures. The sheet carrier concentrations determined from Shubnikov-de Haas magnetoresistance oscillations were in good agreement with the Hall data. The electron effective mass was determined to be 0.215±0.006 m0 based on the temperature dependence of the amplitude of Shubnikov-de Haas oscillations. The quantum lifetime was about one-fifth of the transport lifetime of 2.3 × 10−12 s.
The microstructure of narrow metal conductors in the electrical interconnections on IC chips has often been identified as of major importance in the reliability of these devices. The stresses and stress gradients that develop in the conductors as a result of thermal expansion differences in the materials and of electromigration at high current densities are believed to be strongly dependent on the details of the grain structure. The present work discusses new techniques based on microbeam x-ray diffraction (MBXRD) that have enabled measurement not only of the microstructure of totally encapsulated conductors but also of the local stresses in them on a micron and submicron scale. White x-rays from the Advanced Light Source were focused to a micron spot size by Kirkpatrick-Baez mirrors. The sample was stepped under the micro-beam and Laue images obtained at each sample location using a CCD area detector. Microstructure and local strain were deduced from these images. Cu lines with widths ranging from 0.8 [.proportional]m to 5 [.proportional]m and thickness of 1 [.proportional]m were investigated. Comparisons are made between the capabilities of MBXRD and the well established techniques of broad beam XRD, electron back scatter diffraction (EBSD) and focused ion beam imagining (FIB).