Phase shift keyed systems based on a gain switched laser transmitter.

Return-to-Zero (RZ) and Non-Return-to-Zero (NRZ) Differential Phase Shift Keyed (DPSK) systems require cheap and optimal transmitters for widespread implementation. The authors report on a gain switched Discrete Mode (DM) laser that can be employed as a cost efficient transmitter in a 10.7 Gb/s RZ DPSK system and compare its performance to that of a gain switched Distributed Feed-Back (DFB) laser.

Ethical issues in psychiatric research.

The field of psychiatric research ethics has evolved in recent years. This evolution seems to stem from the efforts of various groups (eg, medical ethicists, regulatory bodies, and the profession's own association, the APA) and from increased understanding of the endeavor of psychiatric empirical research. Current data regarding mental illness highlight the need for the continued expansion of psychiatric research to help relieve the suffering of the many individuals whom mental illness affects.

Differences in self-reported disclosure of college experiences by first-generation college student status.

Disclosure of stressful life experiences is described here as a potential means of stress reduction and as a potential indicator of available support. This study compared reports of the disclosure of college experiences by college freshmen (N = 1,539). Using a student survey conducted at four universities across the country, disclosure by first-generation student status was compared.

Emotion and eating psychopathology: links with attitudes toward emotional expression among young women.

Objective: The aim of this study was to determine links between attitudes toward emotional expression and levels of eating psychopathology among young women.

Method: Eighty-nine young female volunteers completed the Attitudes Toward Emotional Expression scale (AEE) and the Eating Disorders Examination Questionnaire (EDEQ).

Results: There were positive significant associations between AEE subscales and EDEQ scores.

Clinical signs and symptoms of oropharyngeal aspiration and dysphagia in children.

The diagnostic value of various signs and symptoms (clinical markers) in predicting oropharyngeal aspiration (OPA) or swallowing dysfunction has not been established in children. The present retrospective study was undertaken to: 1) identify specific clinical markers associated with radiographic evidence of OPA, isolated laryngeal penetration (ILP) and post-swallow residue (PSR); 2) determine the sensitivity and specificity of clinical markers associated with OPA; and 3) determine the influence of age and neurological impairment on clinical markers of OPA. In total, 11 clinical markers of dysphagia were compared with the videofluoroscopic swallow study (VFSS) results (OPA, ILP and PSR) in 150 children on diets of thin fluid and purée consistencies.

Polarization dependence of a GaAs-based two-photon absorption microcavity photodetector.

In this paper, the polarization response of a GaAs based two-photon absorption microcavity photodetector has been studied. The deviation in the dependence of the detector response from that of bulk GaAs is shown to be due to the birefringence of the cavity. A theoretical model based on the convolution of the cavity birefringence and the polarization dependence of two-photon absorption in GaAs is described and shown to match the measured polarization dependence of the microcavity detector very well.

The effect of a self-monitored relaxation breathing exercise on male adolescent aggressive behavior.

This study sought to contribute to the identification of effective interventions in the area of male adolescent aggressive behavior. Existing research includes both group- and single-case studies implementing treatments which typically include an anger-management component and its attendant relaxation and stress-reduction techniques. The design of this study was single-subject with multiple baselines across 6 subjects on 2 behavioral measures.

Optimization of a 42.7 Gb/s wavelength tunable RZ transmitter using a linear spectrogram technique.

The optimization of a wavelength tunable RZ transmitter, consisting of an electro-absorption modulator and a SG DBR tunable laser, is carried out using a linear spectrogram based characterization and leads to 1500 km transmission at 42.7 Gb/s independent of the operating wavelength. We demonstrate that, to ensure optimum and consistent transmission performance over a portion of the C-band, the RF drive and bias conditions of the EAM must be varied at each wavelength.

Characterisation of an optical clock recovery method based on a mode-locked laser diode using spectrographic pulse measurement.

As channels rates in optical networks are expected to exceed 100 Gb/s in the near future, new optical techniques for clock recovery will have to be developed for optical regeneration. This paper describes an optical clock recovery method based on a mode-locked laser diode. Experimental results show that a 42 GHz high quality optical clock can be retrieved from a 170 Gb/s OTDM data signal.

Higher burden of depression among older women: the effect of onset, persistence, and mortality over time.

Context: The prevalence of depression is disproportionately higher in older women than men, yet the reasons for this sex difference are not clear.

Objective: To determine whether the higher burden of depression among older women than men might be attributable to sex differences in the onset (ie, first or recurrent episodes) or persistence of depression and/or to differential mortality among those who are depressed.

Design: Prospective cohort study.

Complete pulse characterization at 1.5 mum by cross-phase modulation in optical fibers.

Cross-phase modulation in optical fibers has been used for complete characterization of ultrashort pulses by a modified frequency-resolved optical gating (FROG) measurement technique. This technique has been used for characterization of picosecond pulses at 1.5mum with energy as low as 24 pJ, and the results are in excellent agreement with second-harmonic generation (SHG)-FROG characterization.

Association between angina and treatment satisfaction after myocardial infarction.

Background: Patient satisfaction is increasingly recognized as a quality indicator and important outcome of care. Little is known about the clinical factors associated with satisfaction after myocardial infarction (MI).

Objective: To assess the hypothesis that angina after MI is independently associated with lower treatment satisfaction.

Oropharyngeal aspiration and pneumonia in children.

Oropharyngeal aspiration (OPA) of food and fluids is known to be associated with pneumonia in dysphagic children with neurological disease and direct causality is often assumed. However, little is known about the relationship between OPA and pneumonia in medically complex children when other possible risk factors for pneumonia are considered. We examined the association of World Health Organization (WHO)-defined pneumonia in a heterogeneous group of children with swallowing dysfunction identified by a videofluoroscopic swallow study (VFSS).

Patient satisfaction with treatment after acute myocardial infarction: role of psychosocial factors.

Objective: To determine if psychosocial status influences treatment satisfaction, a quality-of-care indicator, of patients who were hospitalized for acute myocardial infarction (AMI).

Methods: Psychosocial variables (social support, dispositional optimism, and depression) were assessed in 1847 AMI patients who completed a 1-month assessment in Prospective Registry Evaluating Myocardial Infarction: Events and Recovery (PREMIER), a multicenter, prospective cohort study. Patients' treatment satisfaction was determined using the Treatment Satisfaction scale of the Seattle Angina Questionnaire.

Perceived control and change in physical functioning after coronary artery bypass grafting: a prospective study.

We determined if perceived general and health-related control predicted change in physical functioning after coronary artery bypass grafting (CABG) in 1,038 patients. Control and physical functioning were assessed prior to hospital discharge and physical functioning also was assessed 6 weeks and 6 months later. The repeated measures outcome was modeled using a one-way analysis of covariance with interaction terms for General and Health-Related Control x Time.

Social support and change in health-related quality of life 6 months after coronary artery bypass grafting.

Objective: We determined whether perceived social support predicted change in health-related quality of life, operationalized as change in mental health and physical functioning, 6 months after coronary artery bypass grafting (CABG).

Methods: A prospective cohort of 1164 patients undergoing first CABG was interviewed prior to hospital discharge and 6 months later. Perceived instrumental and emotional support were assessed predischarge.

Identification of pain-reduction strategies used by community-dwelling older persons.

Background: The types of methods used by older persons to reduce chronic pain have not been adequately characterized. In this cross-sectional study of older persons with chronic nonmalignant pain, we sought to identify strategies perceived as effective in reducing pain and to ascertain factors associated with their use.

Methods: Participants included 272 community-dwelling persons aged 73 years or older.

Signal degradation due to output filtering of self-seeded gain-switched pulses exhibiting weak inherent side-mode-suppression ratios.

We show the importance of achieving an acceptable level of output side-mode-suppression ratio when generating pulses by using the self-seeded gain-switched technique. Experiments carried out on such pulses exhibiting poor side-mode-suppression ratios that are subsequently filtered to improve the latter demonstrate that they possess an associated level of noise. This buildup of noise with a decreasing inherent side-mode-suppression ratio is noted regardless of the improved output-filtered side-mode-suppression ratio of 35 dB that is maintained.

A pilot study of cytokine levels and white blood cell counts in the diagnosis of necrotizing fasciitis.

Study Objectives: To characterize the early cytokine response of patients presenting to the emergency department with necrotizing fasciitis (NF) and to determine whether serum cytokine levels and white blood cell (WBC) counts may be useful in distinguishing NF from other severe soft-tissue infections.

Methods: White blood cell counts and cytokine levels (IL-1beta, IL-1Ra, IL-6, IL-8, IL-18, and IFN-gamma) were measured in patients presenting to the emergency department with severe soft-tissue infections and high suspicion of NF. Necrotizing fasciitis was confirmed intraoperatively and by surgical pathology.

Identification of strategies used to cope with chronic pain in older persons receiving primary care from a Veterans Affairs Medical Center.

Objectives: To identify the strategies used by older persons to cope with chronic noncancer pain, determine the perceived effectiveness of the strategies, and ascertain factors associated with their use.

Design: Cross-sectional telephone survey.

Setting: Primary care practice located at a Veterans Affairs Medical Center in New England.

Decreased peritoneal macrophage NF-kappaB translocation to the nucleus in protein energy malnutrition--a role for the glucocorticoid response?

Background & Aims: Protein energy malnutrition (PEM) induces immune suppression leading to increased morbidity and mortality. The mechanism(s) underlying PEM-mediated immune suppression remain unclear. Plasma glucocorticoid levels are elevated in PEM and it has been postulated that these increased levels may mediate macrophage (MØ) dysfunction in PEM.

Cognitive-behavioral therapy for chronic low back pain in older persons: a preliminary study.

Objective: To determine the feasibility and potential efficacy of providing cognitive-behavioral therapy (CBT) to older persons with chronic low back pain (CLBP).

Methods: This was an uncontrolled pilot study conducted at a senior housing center (SHC) in New Haven, Connecticut. Fourteen SHC residents aged 65 years and older who were cognitively intact (Mini Mental State Examination score > or =24) and had CLBP were recruited for the study.

Functional self-efficacy and pain-related disability among older veterans with chronic pain in a primary care setting.

We examined the relationship between functional self-efficacy and pain-related disability in a sample of older veterans with chronic pain. A total of 1045 veterans aged 65 years or older who received primary care at the VA Connecticut Healthcare System in West Haven, CT, were assessed for the presence of chronic pain (i.e.