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We conducted a retrospective study of the appropriateness of antimicrobial agents prescribed on discharge from an acute care hospital. Seventy percent of discharge antibiotics were inappropriate in antibiotic drug choice, dose, or duration. Our findings suggest there is a significant need for antimicrobial stewardship at transitions in care.
We present MERLIN maps of V1016 Cyg at 6 cm, observed on 1992 July 21 and 1995 March 23. Previously discovered bipolar structure is resolved into three distinct peaks. Evolution and proper motion of these peaks has been measured.
Little is known about predictors of recovery from bipolar depression.
We investigated affective instability (a pattern of frequent and large mood shifts over time) as a predictor of recovery from episodes of bipolar depression and as a moderator of response to psychosocial treatment for acute depression.
A total of 252 out-patients with DSM-IV bipolar I or II disorder and who were depressed enrolled in the Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD) and were randomised to one of three types of intensive psychotherapy for depression (n = 141) or a brief psychoeducational intervention (n = 111). All analyses were by intention-to-treat.
Degree of instability of symptoms of depression and mania predicted a lower likelihood of recovery and longer time until recovery, independent of the concurrent effects of symptom severity. Affective instability did not moderate the effects of psychosocial treatment on recovery from depression.
Affective instability may be a clinically relevant characteristic that influences the course of bipolar depression.
Individuals with major depressive disorder (MDD) are characterized by maladaptive responses to both positive and negative outcomes, which have been linked to localized abnormal activations in cortical and striatal brain regions. However, the exact neural circuitry implicated in such abnormalities remains largely unexplored.
In this study 26 unmedicated adults with MDD and 29 matched healthy controls (HCs) completed a monetary incentive delay task during functional magnetic resonance imaging (fMRI). Psychophysiological interaction (PPI) analyses probed group differences in connectivity separately in response to positive and negative outcomes (i.e. monetary gains and penalties).
Relative to HCs, MDD subjects displayed decreased connectivity between the caudate and dorsal anterior cingulate cortex (dACC) in response to monetary gains, yet increased connectivity between the caudate and a different, more rostral, dACC subregion in response to monetary penalties. Moreover, exploratory analyses of 14 MDD patients who completed a 12-week, double-blind, placebo-controlled clinical trial after the baseline fMRI scans indicated that a more normative pattern of cortico-striatal connectivity pre-treatment was associated with greater improvement in symptoms 12 weeks later.
These results identify the caudate as a region with dissociable incentive-dependent dACC connectivity abnormalities in MDD, and provide initial evidence that cortico-striatal circuitry may play a role in MDD treatment response. Given the role of cortico-striatal circuitry in encoding action–outcome contingencies, such dysregulated connectivity may relate to the prominent disruptions in goal-directed behavior that characterize MDD.
The course of bipolar disorder progressively worsens in some patients. Although responses to pharmacotherapy appear to diminish with greater chronicity, less is known about whether patients' prior courses of illness are related to responses to psychotherapy.
Embedded in the Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD) was a randomized controlled trial of psychotherapy for bipolar depression comparing the efficacy of intensive psychotherapy with collaborative care (a three-session psycho-educational intervention). We assessed whether the number of previous mood episodes, age of illness onset, and illness duration predicted or moderated the likelihood of recovery and time until recovery from a depressive episode in patients in the two treatments.
Independently of treatment condition, participants with one to nine prior depressive episodes were more likely to recover and had faster time to recovery than those with 20 or more prior depressive episodes. Participants with fewer than 20 prior manic episodes had faster time to recovery than those with 20 or more episodes. Longer illness duration predicted a longer time to recovery. Participants were more likely to recover in intensive psychotherapy than collaborative care if they had 10–20 prior episodes of depression [number needed to treat (NNT) = 2.0], but equally likely to respond to psychotherapy and collaborative care if they had one to nine (NNT = 32.0) or >20 (NNT = 9.0) depressive episodes.
Number of previous mood episodes and illness duration are associated with the likelihood and speed of recovery among bipolar patients receiving psychosocial treatments for depression.
Preliminary work indicates that cognitive vulnerability to depression may be associated with variants of the serotonin transporter promoter polymorphism (5-HTTLPR) and the valine to methionine at position 66 (val66met) polymorphism of the brain-derived neurotrophic factor (BDNF) gene; however, existing reports come from small samples. The present study sought to replicate and extend this research in a sample of 375 community-dwelling children and their parents. Following a negative mood induction, children completed a self-referent encoding task tapping memory for positive and negative self-descriptive traits. Consistent with previous work, we found that children with at least one short variant of the 5-HTTLPR had enhanced memory for negative self-descriptive traits. The BDNF val66met polymorphism had no main effect but was moderated by maternal depression, such that children with a BDNF methionine allele had a heightened memory for negative self-descriptive traits when mothers had experienced depression during children's lifetimes; in contrast, children with a methionine allele had low recall of negative traits when mothers had no depression history. The findings provide further support for the notion that the 5-HTTLPR is associated with cognitive markers of depression vulnerability and that the BDNF methionine allele moderates children's sensitivity to contextual factors.
The Dominion Radio Astrophysical Observatory (DRAO) is carrying out a survey as part of an international collaboration to image the northe, at a common resolution, in emission from all major constituents of the interstellar medium; the neutral atomic gas, the molecular gas, the ionised gas, dust and relativistic plasma. For many of these constituents the angular resolution of the images (1 arcmin) will be more than a factor of 10 better than any previous studies. The aim is to produce a publicly-available database of high resolution, high-dynamic range images of the Galaxy for multi-phase studies of the physical states and processes in the interstellar medium. We will sketch the main scientific motivations as well as describe some preliminary results from the Canadian Galactic Plane Survey/Releve Canadien du Plan Galactique (CGPS/RCPG).
ZnSe/GaAs heterojunctions were investigated by contactless electroreflectance and photoreflectance techniques. Negative surface charge densities on the order of 1012 cm-2 were observed for films grown on n-type GaAs indicating a large contribution to the conduction band barrier between the materials due to band bending. The conduction band offset was also measured using a new photoreflectance technique involving a tunable pump laser.
Neuroimaging research has demonstrated medial prefrontal cortex (mPFC) hyporesponsivity and amygdala hyperresponsivity to trauma-related or emotional stimuli in post-traumatic stress disorder (PTSD). Relatively few studies have examined brain responses to the recollection of stressful, but trauma-unrelated, personal events in PTSD. In the current study, we sought to determine whether regional cerebral blood flow (rCBF) abnormalities in mPFC and amygdala in PTSD could be observed during the recollection of trauma-unrelated stressful personal events.
Participants were 35 right-handed male combat veterans (MCVs) and female nurse veterans (FNVs) who served in Vietnam: 17 (seven male, 10 female) with current military-related PTSD and 18 (nine male, nine female) with no current or lifetime PTSD. We used positron emission tomography (PET) and script-driven imagery to study rCBF during the recollection of trauma-unrelated stressful versus neutral and traumatic events.
Voxelwise tests revealed significant between-group differences for the trauma-unrelated stressful versus neutral comparison in mPFC, specifically in the anterior cingulate cortex (ACC). Functional region of interest (ROI) analyses demonstrated that this interaction in mPFC represented greater rCBF decreases in the PTSD group during trauma-unrelated stressful imagery relative to neutral imagery compared to the non-PTSD group. No differential amygdala activation was observed between groups or in either group separately.
Veterans with PTSD, compared to those without PTSD, exhibited decreased rCBF in mPFC during mental imagery of trauma-unrelated stressful personal experiences. Functional neuroanatomical models of PTSD must account for diminished mPFC responses that extend to emotional stimuli, including stressful personal experiences that are not directly related to PTSD.
Compositions in the PNN-PMW-PT system can be tailored to give high dielectric constant for MLC applications. Low temperature firing of MLC is always advantageous in using the less expensive electrode systems. Controlled addition of LiNO3 reduces the sintering temperature, increases the fired density and influences the microstructure of the ceramics. It also raises the peak dielectric constant and shifts the Curie temperature. The possible role of Li+ in modifying the characteristics of the ceramics is discussed.
Composition control in lead or bismuth based ferroelectric thin films was studied for rf magnetron, dc magnetron and ion beam sputter depositions with metal or oxide targets. For room temperature depositions, (1) control of the target surfaces, (2) suppression of harmful effects from negative ions and (3) control of oxygen content in the films were significant. The surface of the lead target gradually degrades and alters the lead flux extracted from the target. At low pressures resputtering from the film occurs by negative oxygen ions. It is necessary to put more oxygen into the films in the sputter depositions with metal targets and the ion beam sputter depositions. For high temperature depositions, a composition self control was observed for films deposited in excess lead environments.
A novel, low-cost, phased-array antenna that uniquely incorporates bulk phase shifting using voltage-tunable dielectric (VTD) material is presented. The array does not contain an individual phase shifter at each radiating element. This paper presents the antenna concept and describes how it can be used as a low-cost phased array. The VTDs that are used in this antenna are described. The measured antenna patterns of a prototype phased array demonstrating electronic beam scanning at 10 GHz are also presented.
Samples of yellow-fever vaccine prepared from homogenized chick embryos, and of an experimental measles vaccine prepared from chick embryo cells, have each been shown to contain a contaminant virus similar in properties to an avian leukosis virus. Young adult males injected with the yellow-fever vaccine did not develop neutralizing antibodies for Rous sarcoma virus.
Whitham's averaged Lagrangian method is used to yield a relativistically covariant formalism for wave packets in a weakly inhomogeneous (and time dependent) medium. Provided the physics of the medium can be based on a Lagrangian density, a procedure of expansion and averaging is available which gives separate Lagrangians for the dynamics of the background and of the waves. The Euler—Lagrange equations then give immediately the equations of motion for the background, including non-linear reaction of the waves, and the dispersion relation, equations for ray tracing, conservation of wave action and non-linear coupling coefficients, for the waves. Many of these results can be interpreted in an illuminating way by considering the corresponding expansion of the canonical four-dimensional stress tensor.