Reduced linewidth re-broadening by suppressing longitudinal spatial hole burning in high-power 1.55-/spl mu/m continuous-wave distributed-feedback (CW-DFB) laser diodes

For the first time, the impact of longitudinal photon density distribution and longitudinal carrier density distribution on the spectral linewidth re-broadening effect in single-electrode 1.55-/spl mu/m distributed feedback (DFB) laser diodes (LDs) is investigated experimentally in details. By optimizing the front-to-rear facet power ratio, the nonuniformity of the photon density distribution along the laser cavity is reduced, hence reducing the degree of longitudinal spatial hole burning (SHB). Using this optimized value of front-to-rear facet power ratio, the degree of longitudinal SHB can be further reduced through reduction of the nonuniformity of the longitudinal carrier density distribution by increasing the cavity length. As a result, the local stimulated emission is reduced, hence reducing linewidth re-broadening caused by longitudinal SHB. The outcomes of this analysis is being used fruitfully to design high-power 1.55-/spl mu/m DFB LDs exhibiting very narrow spectral linewidth of approximately 1.3 MHz at an output power of 175 mW under continuous-wave operation.     

Analysis of SAW attenuation measurement using acoustic microscopy

Effect of acoustic loss in solids on depths of dips in V(z) curves obtained by reflection acoustic microscopy was calculated. The results were in good agreement with the observed V(z) curves of steels. The applicability and limitations of measuring attenuation of surface acoustic waves from V(z) curves are discussed.     

Correlation between equation of state and temperature and pressure dependence of self-diffusion coefficient of polymers and simple liquids

Correlation between the equation of state and the temperature dependence of the self-diffusion coefficient D for polymers such as polystyrene (PS) and polydimethyl siloxane (PDMS) and simple liquids such as argon, methane and benzene and the pressure dependence of D for oligomers such as dimethyl siloxane (DMS) and simple liquids such as cyclohexane and methanol has been examined based on the equation of state derived previously. The experimental data used were published by Antonietti et al. and McCall et al. for polymers, by McCall for linear dimethylsiloxanes and by Jonas et al. and Woolf et al. for simple liquids. The expression for D in this work is given by

where A₁(M) is a function of molecular weight M_w, C₁(T) and P₁(T) are functions of temperature and B₁, n₁ and m₁ are constants determined experimentally. For simple liquids, the values of n₁ obtained range from 0.3 to 1.2, with an average , and m₁ is in the range 0.5–1.2, with . For polymers, values of n₁ are in the range 2.5–7.0 for PS and 0.5–1.3 for PDMS and m₁ for DMS is in the range 0.8–1.0. The relation Dη/T = f(M) is found to be useful for simple liquids over a wide range of temperature including the critical region and for pressures up to ≈5 kbar

1 kbar = 100 MPa There is a close correlation between ln(D/T) and _p and β_T through ln(D/T)ln D_c−⁻¹_p−β⁻¹_T, where D_c is D at the critical temperature and _p and β_T are the thermal expansion coefficient and compressibility, respectively. The molecular weight dependence of D for polymers and simple liquids is discussed based on the experimental data and recent theory of Doi and Edwards. A new model for the mechanism of self-diffusion in the liquid state is proposed.     

A disjoint path selection scheme with shared risk link groups in GMPLS networks

This letter proposes a disjoint path selection scheme for generalized multi-protocol label switching (GMPLS) networks with shared risk link group (SRLG) constraints. It is called the weighted-SRLG (WSRLG) scheme. It treats the number of SRLG members related to a link as part of the link cost when the k-shortest path algorithm is executed. In WSRLG, a link that has many SRLG members is rarely selected as the shortest path. Simulation results show that WSRLG finds more disjoint paths than the conventional k-shortest path algorithm.     

Millimeter Wave Imaging System Using Monopole Antenna with Cylindrical Reflector and Silicon Lens

We built a reflection imaging system that uses a monopole antenna with a cylindrical reflector and silicon semi-spherical lens for millimeter waves to identify detachments of alabaster from support material such as wood and stone, which can be subject to painting deterioration. Based on the electric field property near the monopole antenna in the system and the lens effect, the system was able to clearly image a test sample made of 2-mm width aluminium tape, which was placed within a range of approximately 10 mm from the lens. In practical imaging testing using a detachment model, which consists of alabaster and wood plating, the result also showed the possibility of observing slight detachment of the alabaster from the wood more easily than an imaging with large numerical aperture.     

Numerical analysis of static wavelength shift for DFB lasers with longitudinal mode spatial hole burning

The static wavelength shift induced by longitudinal mode spatial hole burning is analyzed numerically for lambda /4-shifted DFB lasers. The effective Bragg wavelength at each bias level is introduced to clarify the contribution of nonuniformity in carrier density distribution to the lasing wavelength shift. It is shown that the wavelength shift is caused by two separate factors: by the position-dependent deviation and by the average value in the exact N/sub eq/ distribution. The former factor induces both red- and blue-shifted tuning due to the nonuniformity itself in carried density distribution, while the latter results in blue-shifted tuning due to the increase in modal gain.<>     

Molecular characterization of Ypi1, a novel Saccharomyces cerevisiae type 1 protein phosphatase inhibitor

The Saccharomyces cerevisiae open reading frame YFR003c encodes a small (155-amino acid) hydrophilic protein that we identified as a novel, heat-stable inhibitor of type 1 protein phosphatase (Ypi1). Ypi1 interacts physically in vitro with both Glc7 and Ppz1 phosphatase catalytic subunits, as shown by pull-down assays. Ypi1 inhibits Glc7 but appears to be less effective toward Ppz1 phosphatase activity under the conditions tested. Ypi1 contains a 48RHNVRW53 sequence, which resembles the characteristic consensus PP1 phosphatase binding motif. A W53A mutation within this motif abolishes both binding to and inhibition of Glc7 and Ppz1 phosphatases. Deletion of YPI1 is lethal, suggesting a relevant role of the inhibitor in yeast physiology. Cells overexpressing Ypi1 display a number of phenotypes consistent with an inhibitory role of this protein on Glc7, such as decreased glycogen content and an increased growth defect in a slt2/mpk1 mitogen-activated protein kinase-deficient background. Taking together, these results define Ypi1 as the first inhibitory subunit of Glc7 identified in budding yeast.     

Acute tuberculous bronchiolitis in a patient with generalized miliary tuberculosis]

A case study of an acute tuberculous bronchiolitis (a rarely encountered form of generalized miliary tuberculosis), whose aggravated progressing resulted in fatal outcome 2 months after the onset of the initial disease signs, is described. The prevalence of non-specific infectious-and-allergic manifestations is a clinical-and-morphological peculiarity within the case study, which confirms a diversity of morphological changes occurring in the organism in tuberculosis infection. The etiological- and pathogenetic specific features of acute tuberculous bronchiolitis in children and in adults are under discussion; in particular, a possible role of a preceding viral infection is evaluated. It is one of the cases of hematogenic generalization in primary tuberculosis of adults, observed by the authors, when an involvement of the pulmonary and parenchymatous organs as well as of arachnoids and substances of the cerebrum was registered. The presence of generalized vasculitis with fibrinoid swelling and with necrosis of collagenous fibers of medium (and with the development of pan-vasculitis in the discussed case) is typical of all such observations.     

Aplastic anemia in neonatal lupus erythematosus

OBJECTIVE: To describe an infant with neonatal lupus erythematosus associated with aplastic anemia. SETTING: The pediatric department in a tertiary-care hospital. INTERVENTIONS: Packed red blood cell transfusions and a 3-week course of high-dose steroid therapy. MEASUREMENTS/MAIN RESULTS: The patient presented with severe anemia and a circumscribed, reticular, macular rash on the face and neck at 5 months of age. Skin lesion biopsy revealed epidermic hyperkeratosis, hydropic degeneration of the basal layer, and deposition of immunoglobulins and granular C1q at the dermoepidermal junction. Ro/SS-A antibodies were present in the infant. BFU-E (erythroid progenitor burst-forming unit) colonies in bone marrow increased by about tenfold when suppressor CD8+ T lymphocytes were removed, indicating immune suppression of hematopoiesis. High-dose steroid therapy failed. The infant subsequently developed gram-negative sepsis, severe metabolic acidosis, and consumptive coagulopathy and died. CONCLUSIONS: Neonatal lupus erythematosus may present as part of a spectrum. The disease may range from mild and transient to a severe, life-threatening condition requiring immediate intervention, as in the case reported here. This is the first report of neonatal lupus associated with aplastic anemia due to immune-mediated suppression of hematopoiesis.     

Long-term impact of parental divorce on intimate relationship quality in adulthood and the mediating role of psychosocial resources.

The purpose of this 16-year prospective follow-up study was to investigate the association between parental divorce in childhood and intimate relationship quality in adulthood. The mediating role of psychosocial resources (parent-child relationships at 16 years, self-esteem and social support at 32 years) in this association was also studied. All 16 year olds of one Finnish city completed questionnaires at school and were followed up by postal questionnaires at 32 years of age (n = 1,471). Results showed that women and men from divorced families were more often divorced or separated at the age of 32 years than those from nondivorced families. However, parental divorce was associated with poorer intimate relationship quality only among women. Women from divorced families also had poorer relationships with their father and mother in adolescence, and they had lower self-esteem and satisfaction with social support in adulthood than women from intact families. No such associations were found among men. The impact of parental divorce on intimate relationship quality among women was partially mediated by mother-daughter relationship, self-esteem, and satisfaction with social support. The mediating role of mother-daughter relationship was not direct, however, but was mediated via self-esteem and satisfaction with social support. Our findings indicate that parental divorce affects daughters more than sons. In the context of parental divorce, the mother-daughter relationship in adolescence is important for the development of later psychosocial resources and, via them, for intimate relationship quality. (PsycINFO Database Record (c) 2011 APA, all rights reserved)