Suicide and the dexamethasone suppression test in adolescence

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25837/1/0000400.pd

LAGEOS geodetic analysis-SL7.1

Laser ranging measurements to the LAGEOS satellite from 1976 through 1989 are related via geodetic and orbital theories to a variety of geodetic and geodynamic parameters. The SL7.1 analyses are explained of this data set including the estimation process for geodetic parameters such as Earth's gravitational constant (GM), those describing the Earth's elasticity properties (Love numbers), and the temporally varying geodetic parameters such as Earth's orientation (polar motion and Delta UT1) and tracking site horizontal tectonic motions. Descriptions of the reference systems, tectonic models, and adopted geodetic constants are provided; these are the framework within which the SL7.1 solution takes place. Estimates of temporal variations in non-conservative force parameters are included in these SL7.1 analyses as well as parameters describing the orbital states at monthly epochs. This information is useful in further refining models used to describe close-Earth satellite behavior. Estimates of intersite motions and individual tracking site motions computed through the network adjustment scheme are given. Tabulations of tracking site eccentricities, data summaries, estimated monthly orbital and force model parameters, polar motion, Earth rotation, and tracking station coordinate results are also provided

Treatment of adolescents with major depression: implications of the DST and the melancholic clinical subtype

Of 38 adolescents hospitalized with major depression, 47% of those receiving psychosocial treatment alone responded. Of the non-responders then treated with combined tricyclic antidepressants and psychosocial treatment, 92% responded. The melancholic subtype and dexamethasone suppression test non-suppression were associated with failure to respond to psychosocial treatment alone. Implications for controlled studies are discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/27768/1/0000162.pd

Panic and depressive disorders among psychiatrically hospitalized adolescents

Sixty-one adolescents hospitalized on an inpatient psychiatric unit were evaluated to determine whether they met criteria for panic and affective disorders according to Research Diagnostic Criteria. Ten (16%) and 15 (24%) met criteria for definite or possible panic disorder. Fifteen (24.5%) had major depressive disorder (MDD) endogenous subtype, 10 (16%) had MDD nonendogenous subtype, 8 (13%) had minor depressive disorder (mDD), and 27 (44%) had no diagnosable mood disorder. Four adolescents with definite panic disorders were diagnosed as having MDD endogenous subtype, three MDD, two mDD, and one had no diagnosable depressive disorder. The mean total score on the Hamilton Rating Scale for Depression (HRSD) was significantly higher among those subjects with definite panic attacks compared with those with either possible or no panic. Patients with definite panic disorder showed significant increases on the HRSD items of guilt, decreased work and interest, psychological and somatic anxiety, and weight loss compared to these samples.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26753/1/0000305.pd

Use of the Hamilton rating scale for depression and the Carroll self-rating scale in adolescents

The relationship of clinicians' ratings of depression in adolescents to self-rating is important to clinical research. The Hamilton Rating Scale for Depression (HRSD) and the Carroll Self-Rating Scale (CSRS) were compared in a study of 81 psychiatrically hospitalized adolescents. The correlation of CSRS and HRSD total scores in adolescents with melancholic major depression was 0.46, lower than the correlation reported in adults (0.80). Higher correlations were seen in females and in nonmelancholic and nondepressed subgroups. While the comparison of the two rating methods suggests some characteristics of depressed adolescents' presentation of their illness, it does not appear that the self-rating instrument can be used as an alternative to clinicians' ratings.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25763/1/0000324.pd

Building a Better Racetrack

We find IIb compactifications on Calabi-Yau orientifolds in which all Kahler moduli are stabilized, along lines suggested by Kachru, Kallosh, Linde and Trivedi.Comment: 47 pages, 1 figure, harvmac (v2: added references, minor comments, v3: improved discussion of metastability and explicit flux vacua

Dirac theory on a space with linear Lie type fuzziness

A spinor theory on a space with linear Lie type noncommutativity among spatial coordinates is presented. The model is based on the Fourier space corresponding to spatial coordinates, as this Fourier space is commutative. When the group is compact, the real space exhibits lattice characteristics (as the eigenvalues of space operators are discrete), and the similarity of such a \emph{lattice} with ordinary lattices is manifested, among other things, in a phenomenon resembling the famous \emph{fermion doubling} problem. A projection is introduced to make the dynamical number of spinors equal to that corresponding to the ordinary space. The actions for free and interacting spinors (with Fermi-like interactions) are presented. The Feynman rules are extracted and 1-loop corrections are investigated.Comment: 1+14 pages, no figure

On Supergravity Solutions of Branes in Melvin Universes

We study supergravity solutions of type II branes wrapping a Melvin universe. These solutions provide the gravity description of non-commutative field theories with non-constant non-commutative parameter. Typically these theories are non-supersymmetric, though they exhibit some feature of their corresponding supersymmetric theories. An interesting feature of these non-commutative theories is that there is a critical length in the theory in which for distances larger than this length the effects of non-commutativity become important and for smaller distances these effects are negligible. Therefore we would expect to see this kind of non-commutativity in large distances which might be relevant in cosmology. We also study M5-brane wrapping on 11-dimensional Melvin universe and its descendant theories upon compactifying on a circle.Comment: 25 pages, latex file; v2: typos corrected, Refs. adde

On Instanton Effects in F-theory

We revisit the issue of M5-brane instanton corrections to the superpotential in F-theory compactifications on elliptically fibered Calabi-Yau fourfolds. Elaborating on concrete geometries, we compare the instanton zero modes for non-perturbative F-theory models with the zero modes in their perturbative Sen limit. The fermionic matter zero modes localized on the intersection of the instanton with the space-time filling D7-branes show up in a geometric way in F-theory. Methods for their computation are developed and, not surprisingly, exceptional gauge group structures do appear. Finally, quite intriguing geometrical aspects of the one-loop determinant are discussed.Comment: 52 pages, 8 figures, 13 tables; v2: extended discussion of matter zero modes, refs added; v3: sections 3.3 + 4.1 restructure

Gaugino Condensation and Nonperturbative Superpotentials in Flux Compactifications

There are two known sources of nonperturbative superpotentials for K\"ahler moduli in type IIB orientifolds, or F-theory compactifications on Calabi-Yau fourfolds, with flux: Euclidean brane instantons and low-energy dynamics in D7 brane gauge theories. The first class of effects, Euclidean D3 branes which lift in M-theory to M5 branes wrapping divisors of arithmetic genus 1 in the fourfold, is relatively well understood. The second class has been less explored. In this paper, we consider the explicit example of F-theory on $K3 \times K3$ with flux. The fluxes lift the D7 brane matter fields, and stabilize stacks of D7 branes at loci of enhanced gauge symmetry. The resulting theories exhibit gaugino condensation, and generate a nonperturbative superpotential for K\"ahler moduli. We describe how the relevant geometries in general contain cycles of arithmetic genus $\chi \geq 1$ (and how $\chi > 1$ divisors can contribute to the superpotential, in the presence of flux). This second class of effects is likely to be important in finding even larger classes of models where the KKLT mechanism of moduli stabilization can be realized. We also address various claims about the situation for IIB models with a single K\"ahler modulus.Comment: 24 pages, harvmac, no figures, references adde