7 research outputs found
Intimate Monolithic integration of Chip-scale Photonic Circuits
Cataloged from PDF version of article.In this paper, we introduce a robust monolithic integration technique for fabricating photonic integrated circuits comprising optoelectronic devices (e.g., surface-illuminated photodetectors, waveguide quantum-well modulators, etc.) that are made of completely separate epitaxial structures and possibly reside at different locations across the wafer as necessary. Our technique is based on the combination of multiple crystal growth steps, judicious placement of epitaxial etch-stop layers, a carefully designed etch sequence, and self-planarization and passivation steps to compactly integrate optoelectronic devices. This multigrowth integration technique is broadly applicable to most III-V materials and can be exploited to fabricate sophisticated, highly integrated, multifunctional photonic integrated circuits on a single substrate. As a successful demonstration of this technique, we describe integrated photonic switches that consume only a 300 x 300 mu m footprint and incorporate InGaAs photodetector mesas and InGaAsP/InP quantum-well modulator waveguides separated by 50 mu m on an InP substrate. These switches perform electrically-reconfigurable optically-controlled wavelength conversion at multi-Gb/s data rates over the entire center telecommunication wavelength band
Panic disorder severity scale: Reliability and validity of the Turkish version
We assessed the reliability and validity of the Turkish version of the seven-item Panic Disorder Severity Scale (PDSS). We recruited 174 subjects, including 104 with current DSM-IV panic disorder with (n = 76) or without (n = 28) agoraphobia, 14 with a major depressive episode, 24 with a non-panic anxiety disorder, and 32 healthy controls. Assessment instruments were Panic Disorder Severity Scale, Panic and Agoraphobia Scale, both the observer-rated (P&Ao) and self-rating (PAsr); Clinical Global Impression Scale (CGI); Hamilton Anxiety Scale, and Beck Depression Inventory. We repeated the measures for a group of panic disorder patients (n = 51) after 4 weeks to assess test-retest reliability. The internal consistency (Cronbach's alpha) of the PDSS was .92-94. The inter-rater correlation coefficient was .79. The test-retest correlation coefficient after 4 weeks was .63. In discriminant validity analyses, the highest correlation for PDSS was with P&Ao, P&Asr (r =. 87 and. 87, respectively) and CGI (r =. 76) and the lowest with Beck Depression Inventory (r =. 29). The cutoff point was six/seven, associated with high sensitivity (99%) and specificity (98%). This study confirmed the objectivity, reliability and validity of the Turkish version of the PDSS. (C) 2004 Wiley-Liss, Inc
Combination of Pharmacotherapy With Electroconvulsive Therapy in Prevention of Depressive Relapse A Pilot Controlled Trial
Objective: Relapse rates after electroconvulsive therapy (ECT) remain high with standard treatments. We aimed to test the efficacy of an early administered continuation pharmacotherapy (c-pharm early) strategy in prevention of post-ECT relapse
History of suffocation, state-trait anxiety, and anxiety sensitivity in predicting 35% carbon dioxide-induced panic
The aim of this study was to examine the effects of history of suffocation, state-trait anxiety, and anxiety sensitivity on response to a 35% carbon dioxide (CO(2)) challenge in panic disorder patients, their healthy first-degree relatives and healthy comparisons. Thirty-two patients with panic disorder, 32 first-degree relatives, and 34 healthy volunteers underwent the 35% CO(2) challenge. We assessed baseline anxiety with the Anxiety Sensitivity Index (ASI) and State-Trait Anxiety Inventory (STAI1), and panic symptoms with the Panic Symptom List (PSL III-R). A history of suffocation was associated with greater risk of CO(2) reactivity in the combined sample. Patients had more anxiety sensitivity and state and trait anxiety than relatives and healthy comparisons; the difference between relatives and healthy comparisons was not significant. In female patients, trait anxiety predicted CO(2)-induced panic. Having a CO(2)-sensitive panic disorder patient as a first-degree relative did not predict CO(2)-induced panic in a healthy relative. History of suffocation may be an important predictor of CO(2)-induced panic. Trait anxiety may have a gender-specific relation to CO(2) reactivity. (C) 2009 Elsevier Ireland Ltd. All rights reserved