Letters to the Editor

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66389/1/j.1600-0447.1989.tb03017.x.pd

Directional optical coherence tomography provides accurate outer nuclear layer and Henle fiber layer measurements

Purpose: The outer nuclear layer (ONL) contains photoreceptor nuclei, and its thickness is an important biomarker for retinal degenerations. Accurate ONL thickness measurements are obscured in standard optical coherence tomography (OCT) images because of Henle fiber layer (HFL). Improved differentiation of the ONL and HFL boundary is made possible by using directional OCT, a method that purposefully varies the pupil entrance position of the OCT beam. Methods: Fifty-seven normal eyes were imaged using multiple pupil entry positions with a commercial spectral domain OCT system. Cross-sectional image sets were registered to each other and segmented at the top of HFL, the border of HFL and the ONL and at the external limiting membrane. Thicknesses of the ONL and HFL were measured and analyzed. Results: The true ONL and HFL thicknesses varied substantially by eccentricity and between individuals. The true macular ONL thickness comprised an average of 54.6% of measurements that also included HFL. The ONL and HFL thicknesses at specific retinal eccentricities were poorly correlated. Conclusion: Accurate ONL and HFL thickness measurements are made possible by the optical contrast of directional OCT. Distinguishing these individual layers can improve clinical trial endpoints and assessment of disease progression

A longitudinal evaluation of dexamethasone and cortisol plasma concentrations in the dexamethasone suppression test before and during treatment with antidepressant drugs

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66095/1/j.1600-0447.1990.tb03073.x.pd

SUICIDAL IDEATION IN PSORIASIS

Background . Psoriasis has been associated with depressive disease and case reports of completed suicide. Methods . 217 consenting psoriasis patients completed the Carroll Rating Scale for Depression (CRSD), a 52-item self-rated scale, with four of the Items directly addressing wishes to be dead and suicidal ideation. The patients also self-rated the severity of their psoriasis. Results . 9.7% of patients reported a wish to be dead, and 5.5% reported active suicidal ideation at the time of the study. The death wish and suicidal ideation were associated with higher depression scores (P < 0.0001) and higher patient self-ratings of psoriasis severity (P < 0,05). Patient self-reports of psoriasis severity correlated directly with the overall depression scores (r = 0.39), P < 0.0001). Conclusions . The comorbidity between depressive symptoms, suicidal ideation, and psoriasis severity is in contrast with reports that severe depression and suicidal ideation are mainly a feature of life-threatening medical disorders such as malignancies. Our finding may have important implications in the management of psoriasis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65854/1/j.1365-4362.1993.tb02790.x.pd

Psychiatric Aspects of the Treatment of Mild to Moderate Facial Acne

The improvement of acne appears to be associated with decreased depression and anxiety and greater satisfaction with aspects of body image that are generally unrelated to the appearance of the skin, ie, body shape and weight. The latter emphasizes the profound effect of the appearance of the skin upon the patient's overall body image. Our preliminary findings underline the need for larger controlled studies of psychosomatic factors among patients with mild to moderate acne.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65635/1/j.1365-4362.1990.tb03777.x.pd

Resurrecting melancholia

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65798/1/j.1600-0447.2007.00958.x.pd

The Combined Dexamethasone/CRH Test (DEX/CRH Test) and Prediction of Acute Treatment Response in Major Depression

In this study the predictive value of the combined dexamethasone/CRH test (DEX/CRH test) for acute antidepressant response was investigated. In 114 depressed inpatients suffering from unipolar or bipolar depression (sample 1) the DEX/CRH test was performed at admission and shortly before discharge. During their stay in the hospital patients received different antidepressant treatment regimens. At admission, the rate of nonsuppression (basal cortisol levels >75.3 nmol/l) was 24.6% and was not related to the later therapeutic response. Moreover, 45 out of 114 (39.5%) patients showed an enhancement of HPA axis function at discharge in spite of clinical improvement. In a second sample, 40 depressed patients were treated either with reboxetine or mirtazapine for 5 weeks. The DEX/CRH test was performed before, after 1 week, and after 5 weeks of pharmacotherapy. Attenuation of HPA axis activity after 1 week was associated with a more pronounced alleviation of depressive symptoms after 5-week mirtazapine treatment, whereas downregulation of HPA system activity after 5 weeks was related to clinical response to reboxetine. However, early improvement of HPA axis dysregulation was not necessarily followed by a beneficial treatment outcome. Taken together, performance of a single DEX/CRH test does not predict the therapeutic response. The best predictor for response seems to be an early attenuation of HPA axis activity within 1 or 2 weeks. However, early improvement of HPA system dysfunction is not a sufficient condition for a favourable response. Since a substantial part of depressive patients display a persistence of HPA axis hyperactivity at discharge, downregulation of HPA system function is not a necessary condition for acute clinical improvement either. Our data underline the importance of HPA axis dysregulation for treatment outcome in major depression, although restoration of HPA system dysfunction seems to be neither a necessary nor a sufficient determinant for acute treatment response

Sub-Planckian black holes and the Generalized Uncertainty Principle

The Black Hole Uncertainty Principle correspondence suggests that there could exist black holes with mass beneath the Planck scale but radius of order the Compton scale rather than Schwarzschild scale. We present a modified, self-dual Schwarzschild-like metric that reproduces desirable aspects of a variety of disparate models in the sub-Planckian limit, while remaining Schwarzschild in the large mass limit. The self-dual nature of this solution under $M \leftrightarrow M^{-1}$ naturally implies a Generalized Uncertainty Principle with the linear form $\Delta x \sim \frac{1}{\Delta p} + \Delta p$. We also demonstrate a natural dimensional reduction feature, in that the gravitational radius and thermodynamics of sub-Planckian objects resemble that of $(1+1)$-D gravity. The temperature of sub-Planckian black holes scales as $M$ rather than $M^{-1}$ but the evaporation of those smaller than $10^{-36}$g is suppressed by the cosmic background radiation. This suggests that relics of this mass could provide the dark matter.Comment: 12 pages, 9 figures, version published in J. High En. Phy

Goal setting and self-efficacy among delinquent, at-risk and not at-risk adolescents

Setting clear achievable goals that enhance self-efficacy and reputational status directs the energies of adolescents into socially conforming or non-conforming activities. This present study investigates the characteristics and relationships between goal setting and self-efficacy among a matched sample of 88 delinquent (18 % female), 97 at-risk (20 % female), and 95 not at-risk adolescents (20 % female). Four hypotheses related to this were tested. Findings revealed that delinquent adolescents reported fewest goals, set fewer challenging goals, had a lower commitment to their goals, and reported lower levels of academic and self-regulatory efficacy than those in the at-risk and not at-risk groups. Discriminant function analysis indicated that adolescents who reported high delinquency goals and low educational and interpersonal goals were likely to belong to the delinquent group, while adolescents who reported high educational and interpersonal goals and low delinquency goals were likely to belong to the not at-risk group. The at-risk and not at-risk groups could not be differentiated. A multinomial logistic regression also revealed that adolescents were more likely to belong to the delinquent group if they reported lower self-regulatory efficacy and lower goal commitment. These findings have important implications for the development of prevention and intervention programs, particularly for those on a trajectory to delinquency. Specifically, programs should focus on assisting adolescents to develop clear self-set achievable goals and support them through the process of attaining them, particularly if the trajectory towards delinquency is to be addressed

Pulling together: keeping track of pedagogy, design and evaluation through the development of scenarios: a case study

This case study describes the multipurpose use of scenarios in a large multinational research project (MOBIlearn) whose aims are to design and develop a pedagogically sound mobile learning environment. Maintaining effective communication and design focus in large consortia is a wellknown problem (see Carroll, 2000), and we describe the role of scenarios in addressing this. Scenarios were initially used to simply envision the future system in order to inform design, but as the project progressed, the role of the scenarios grew to encompass (i) relating system design and implementation to pedagogy by providing a common frame of reference for developers and pedagogic experts; (ii) through a process of refinement, defining the evaluation strategy for the user trials; and (iii) allowing us to keep the user at the heart of the development project. Thus, scenarios helped to resolve the difficulty identified by Taylor (2004) of how to bring together the relatively high level issues of pedagogic evaluation and the more technical user-centred system evaluation. The development of a first-aid training scenario is used as an illustrative example