Barium strontium titanate glass-ceramics were successfully produced with one major crystalline phase when Al^sub 2^O^sub 3^ was added to the melt. A dielectric constant of 1000 and a breakdown ...strength of 800 kV/cm was achieved; however the energy density was only measured to be 0.3-0.9 J/cm^sup 3^. These energy density values were lower than anticipated due to the presence of dendrites and pores in the microstructure. Using BaF^sub 2^ as a refining agent improved the microstructure and doubled the energy density for BST 80/20 samples. However, no refining agent reduced the increasing amount of hysteresis that developed with increasing applied electric field. This phenomenon is believed to be due to interfacial polarization.PUBLICATION ABSTRACT
We present observations of 77 early-type galaxies imaged with the PC1 CCD of the Hubble Space Telescope (HST) WFPC2. 'Nuker-law' parametric fits to the surface brightness profiles are used to ...classify the central structure into 'core' or 'power-law' forms. Core galaxies are typically rounder than power-law galaxies. Nearly all power-law galaxies with central ellipticities >= 0.3 have stellar disks, implying that disks are present in power-law galaxies with < 0.3 but are not visible because of unfavorable geometry. A few low-luminosity flattened core galaxies also have disks; these may be transition forms from power-law galaxies to more luminous core galaxies, which lack disks. Several core galaxies have strong isophote twists interior to their break radii, although power-law galaxies have interior twists of similar physical significance when the photometric perturbations implied by the twists are evaluated. Central color gradients are typically consistent with the envelope gradients; core galaxies have somewhat weaker color gradients than power-law galaxies. Nuclei are found in 29% of the core galaxies and 60% of the power-law galaxies. Nuclei are typically bluer than the surrounding galaxy. While some nuclei are associated with active galactic nuclei (AGNs), just as many are not; conversely, not all galaxies known to have a low-level AGN exhibit detectable nuclei in the broadband filters. NGC 4073 and 4382 are found to have central minima in their intrinsic starlight distributions; NGC 4382 resembles the double nucleus of M31. In general, the peak brightness location is coincident with the photocenter of the core to a typical physical scale of <1 pc. Five galaxies, however, have centers significantly displaced from their surrounding cores; these may be unresolved asymmetric double nuclei. Finally, as noted by previous authors, central dust is visible in about half of the galaxies. The presence and strength of dust correlates with nuclear emission; thus, dust may outline gas that is falling into the central black hole. The prevalence of dust and its morphology suggest that dust clouds form, settle to the center, and disappear repeatedly on ~108 yr timescales. We discuss the hypothesis that cores are created by the decay of a massive black hole binary formed in a merger. Apart from their brightness profiles, there are no strong differences between core galaxies and power-law galaxies that demand this scenario; however, the rounder shapes of core, their lack of disks, and their reduced color gradients may be consistent with it.
This randomised, double-blind, placebo-controlled, cross-over study was designed to identify which pharmacodynamic parameters most accurately quantify the effects of delta-9-Tetrahydrocannabinol ...(THC), the predominantly psychoactive component of cannabis. In addition, we investigated the acceptability and usefulness of a novel mode of intrapulmonary THC administration using a Volcano® vaporizer and pure THC instead of cannabis. Rising doses of THC (2, 4, 6 and 8 mg) or vehicle were administered with 90 minutes intervals to twelve healthy males using a Volcano® vaporizer. Very low between-subject variability was observed in THC plasma concentrations, characterising the Volcano® vaporizer as a suitable method for the administration of THC. Heart rate showed a sharp increase and rapid decline after each THC administration (8 mg: 19.4 bpm: 95% CI 13.2, 25.5). By contrast, dose dependent effects of body sway (8 mg: 108.5%: 95% CI 72.2%, 152.4%) and different subjective parameters did not return to baseline between doses (Visual Analogue Scales of 'alertness' (8 mg: -33.6 mm: 95% CI -41.6, -25.7), 'feeling high' (8 mg: 1.09 U: 95% CI 0.85, 1.33), 'external perception' (8 mg: 0.62 U: 95% CI 0.37, 0.86)). PK/PD-modeling of heart rate displayed a relatively short equilibration half-life of 7.68 min. CNS parameters showed equilibration half-lives ranging between 39.4 - 84.2 min. Some EEG-frequency bands, and pupil size showed small changes following the highest dose of THC. No changes were seen in saccadic eye movements, smooth pursuit and adaptive tracking performance. These results may be applicable in the development of novel cannabinoid agonists and antagonists, and in studies of the pharmacology and physiology of cannabinoid systems in humans.
The Collaborative Longitudinal Personality Disorders Study (CLPS; Gunderson et al., 2000) was developed to fill gaps in our understanding of the nature, course, and impact of personality disorders ...(PDs). Here, we review published findings to date, discuss their implications for current conceptualizations of PDs, and raise questions that warrant future consideration. We have found that PDs are more stable than major depressive disorder, but that meaningful improvements are possible and not uncommon. We have confirmed also that PDs constitute a significant public health problem, with respect to associated functional impairment, extensive treatment utilization, negative prognostic impact on major depressive disorder, and suicide risk. At the same time, we have demonstrated that dimensional models of PDs have clinical validity that categories do not, especially greater temporal stability. Furthermore, dimensional personality traits appear to be the foundation of behaviors described by many PD criteria. Taken together, our results lead us to hypothesize that PDs may be reconceptualized as hybrids of stable personality traits and intermittently expressed symptomatic behaviors.
Following the appearance of stripe rust in South Africa in 1996, efforts have been made to identify new sources of durable resistance. The French cultivar Cappelle-Desprez has long been considered a ...source of durable, adult plant resistance (APR) to stripe rust. As Cappelle-Desprez contains the seedling resistance genes
Yr3a
and
Yr4a,
wheat lines were developed from which
Yr3a
and
Yr4a
had been removed, while selecting for Cappelle-Desprez derived APR effective against South African pathotypes of the stripe rust fungus,
Puccinia striiformis
f. sp
. tritici.
Line Yr16DH70, adapted to South African wheat growing conditions, was selected and crossed to the stripe rust susceptible cultivar Palmiet to develop a segregating recombinant inbred line mapping population. A major effect QTL,
QYr.ufs
-
2A
was identified on the short arm of chromosome 2A derived from Cappelle-Desprez, along with three QTL of smaller effect,
QYr.ufs
-
2D, QYr.ufs
-
5B
and
QYr.ufs
-
6D. QYr.ufs
-
2D
was located within a region on the short arm of chromosome 2D believed to be the location of the stripe rust resistance gene
Yr16
. An additional minor effect QTL,
QYr.ufs
-
4B,
was identified in the cv. Palmiet. An examination of individual RILs carrying single or combinations of each QTL indicated significant resistance effects when
QYr.ufs
-
2A
was combined with the three minor QTL from Cappelle-Desprez, and between
QYr.ufs
-
2D
and
QYr.ufs
-
5B.
Working within the context of PT-symmetric quantum mechanics, we begin by describing a non-Hermitian extension of QED that is both Lorentz invariant and consistent with unitarity. We show that the ...non-Hermitian Dirac mass matrix of this theory exhibits an exceptional point, corresponding to an effectively massless theory whose conserved current is either right- or left-chiral dominated. With this inspiration, we are able to construct a non- Hermitian model of light Dirac neutrino masses from Hermitian and anti-Hermitian Yukawa couplings that are both of order unity. We finish by highlighting potential phenomenological implications of this model.
Barium strontium titanate (BST) has been targeted as one potential ferroelectric glass–ceramic for high‐energy density dielectric materials. Previous testing has shown that the dielectric constant of ...these materials was as high as 1000 and the dielectric breakdown strength up to 800 kV/cm. This did not, however, result in exceptional energy density (∼0.90 J/cc). In order to increase overall energy density refining agents can be added to the melt, but the nucleation and growth of the ceramic particles can also play a role. Therefore, in this study the crystallization kinetics were studied to more fully understand how BST phase forms so that the optimal energy density could be obtained. It was determined that the activation energy of the crystallization of BST 70/30 glass–ceramic is approximately 430 kJ/mol which is close to the dissociation energy of Si–O bonds. The Avrami parameter was found to be ∼3 meaning that three‐dimensional growth is dominant and the mechanism of growth was interface controlled.
Color has been shown to facilitate both visual search and recognition tasks. It was our purpose to examine the impact of a color-coding algorithm on the interpretation of 2D-DSA acquisitions by ...experienced and inexperienced observers.
Twenty-six 2D-DSA acquisitions obtained as part of routine clinical care from subjects with a variety of cerebrovascular disease processes were selected from an internal data base so as to include a variety of disease states (aneurysms, AVMs, fistulas, stenosis, occlusions, dissections, and tumors). Three experienced and 3 less experienced observers were each shown the acquisitions on a prerelease version of a commercially available double-monitor workstation (XWP, Siemens Healthcare). Acquisitions were presented first as a subtracted image series and then as a single composite color-coded image of the entire acquisition. Observers were then asked a series of questions designed to assess the value of the color-coded images for the following purposes: 1) to enhance their ability to make a diagnosis, 2) to have confidence in their diagnosis, 3) to plan a treatment, and 4) to judge the effect of a treatment. The results were analyzed by using 1-sample Wilcoxon tests.
Color-coded images enhanced the ease of evaluating treatment success in >40% of cases (P < .0001). They also had a statistically significant impact on treatment planning, making planning easier in >20% of the cases (P = .0069). In >20% of the examples, color-coding made diagnosis and treatment planning easier for all readers (P < .0001). Color-coding also increased the confidence of diagnosis compared with the use of DSA alone (P = .056). The impact of this was greater for the naïve readers than for the expert readers.
At no additional cost in x-ray dose or contrast medium, color-coding of DSA enhanced the conspicuity of findings on DSA images. It was particularly useful in situations in which there was a complex flow pattern and in evaluation of pre- and posttreatment acquisitions. Its full potential remains to be defined.
We combine several HST investigations on the central structure of early-type galaxies to generate a large sample of surface photometry. The studies selected were those that used the "Nuker law" to ...characterize the inner light distributions of the galaxies. The sample comprises WFPC1 and WFPC2 V-band observations published earlier by our group, R-band WFPC2 photometry of Rest et al., NICMOS H-band photometry by Ravindranath et al. and Quillen et al., and the brightest cluster galaxy WFPC2 I-band photometry of Laine et al. The distribution of the logarithmic slopes of the central brightness profiles strongly affirms that the central structure of elliptical galaxies with M sub(v) < -19 is bimodal, based on both parametric and nonparametric analysis. At the HST resolution limit, most galaxies are either power-law systems, which have steep cusps in surface brightness, or core systems, which have shallow cusps interior to a steeper envelope brightness distribution. A rapid transition between the two forms occurs over the luminosity range -22 < M sub(v) < -20, with cores dominating at the highest luminosities and power laws at the lowest. There are a few "intermediate" systems that have both cusp slopes and total luminosities that fall within the core/power-law transition, but they are rare and do not fill in the overall bimodal distribution.
Objective: Although much attention has been given to the effects of adverse childhood experiences on the development of personality disorders (PDs), we know far less about how recent life events ...influence the ongoing course of functioning. We examined the extent to which PD subjects differ in rates of life events and the extent to which life events impact psychosocial functioning.
Method: A total of 633 subjects were drawn from the Collaborative Longitudinal Personality Disorders Study (CLPS), a multi‐site study of four personality disorders – schizotypal (STPD), borderline (BPD), avoidant (AVPD), obsessive‐compulsive (OCPD) – and a comparison group of major depressive disorders (MDD) without PD.
Results: Borderline personality disorder subjects reported significantly more total negative life events than other PDs or subjects with MDD. Negative events, especially interpersonal events, predicted decreased psychosocial functioning over time.
Conclusion: Our findings indicate higher rates of negative events in subjects with more severe PDs and suggest that negative life events adversely impact multiple areas of psychosocial functioning.
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