Anisotropy in ac losses near the irreversibility field of Bi2Sr2CaCu2O8

The ac susceptibility under a biased dc field near the irreversibility field (H _irr) of a Bi₂Sr₂CaCu₂O₈ single crystal has been measured. The frequency dependence, the ac-power dependence, and the nearly lossless character of the vs.H _dc curve forHa-axis have been roughly explained from a reversible (elastic) fluxoid motion, while those forH c-axis have been explained from a thermally assisted flux-flow (TAFF) model. The obtained parameters are discussed in relation to anisotropic flux-pinning mechanisms in the layered structure of this compound.     

Analysis of Molecular Species Profiles of Ceramide-1-phosphate and Sphingomyelin Using MALDI-TOF Mass Spectrometry

Ceramide‐1‐phosphate (C1P) is a potential signaling molecule that modulates various cellular functions in animals. It has been known that C1P with different N‐acyl lengths induce biological responses differently. However, molecular species profiles of the C1P in animal tissues have not been extensively examined yet. Here, we developed a method for determination of the molecular species of a C1P using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry with Phos‐tag, a phosphate capture molecule. The amounts of total C1P in skin, brain, liver, kidney and small intestine of mice were determined to be 344, 151, 198, 96 and 90 pmol/g wet weight, respectively. We found a C1P species having an α‐hydroxypalmitoyl residue (h‐C1P, 44 pmol/g wet weight) in mouse skin. The h‐C1P was detected only in the skin, and not other tissues of mice. The same analysis was applied to sphingomyelin after conversion of sphingomyelin to C1P by Streptomyces chromofuscus phospholipase D. We found that molecular species profiles of sphingomyelin in skin, kidney and small intestine of mice were similar to those of C1P in corresponding tissues. In contrast, molecular species profiles of sphingomyelin in liver and brain were quite different from those of C1P in these tissues, indicating selective synthesis or degradation of C1P in these tissues. The method described here will be useful for detection of changes in molecular species profiles of C1P and sphingomyelin.     

Current Diagnosis and Treatment Options for Cutaneous Adnexal Neoplasms with Apocrine and Eccrine Differentiation

Adnexal tumors of the skin are a rare group of benign and malignant neoplasms that exhibit morphological differentiation toward one or more of the adnexal epithelium types present in normal skin. Tumors deriving from apocrine or eccrine glands are highly heterogeneous and represent various histological entities. Macroscopic and dermatoscopic features of these tumors are unspecific; therefore, a specialized pathological examination is required to correctly diagnose patients. Limited treatment guidelines of adnexal tumor cases are available; thus, therapy is still challenging. Patients should be referred to high-volume skin cancer centers to receive an appropriate multidisciplinary treatment, affecting their outcome. The purpose of this review is to summarize currently available data on pathogenesis, diagnosis, and treatment approach for apocrine and eccrine tumors.     

Semiconductor Lasers in Photonics

Research activities on semiconductor lasers related to optical communications and information technologies are reviewed.     

Loss Reduction in a Mesh Waveguide Star Coupler

Abstract

A straight mixing waveguide has been introduced into a mesh waveguide star coupler for the purpose of reducing its excess loss. A preferable structure for a 4 × 4 star coupler has been found by a ray-tracing method. Loss reduction by 3·5 dB compared with a previous structure is demonstrated in an ion-diffused waveguide.     

Research on evaluation methods of generated energy and lowering factors of photovoltaic generation system

Despite substantial progress of research efforts in the field of photovoltaic (PV) power generation, some serious problems remain to be solved, including a fairly low energy generated by PV systems in comparison to the expected output, and a broad spread of output values among individual PV systems. The expected level of generated energy is usually evaluated by means of such coefficients as “the performance ratio” which is obtained as the energy actually generated by a PV array over a period of 1 year divided by the calculated output over the same period. However, this method has some limitations, such as the necessity to continuously perform data measurements over a long time, difficulties in the examination of factors reducing the level of the generated energy or improving the system efficiency, and so on. In this study, the authors propose a new method of accurate evaluation of the generated energy. The authors also examined a method for classifying the losses caused by the rise of the PV cell temperature and presented a method of data measurements over a short time period. The proposed method can also be applied to the classification and analysis of losses occurring at the time of the MPPT operation of the system (P_max operation). © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 154(4): 24–33, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20222     

A study of the merits of a battery combined photovoltaic generation system for a residential house

In this paper we examine the merits that a practical photovoltaic system combining photovoltaic generation with storage batteries would provide if used in ordinary residences. Various configurations and operation methods could be envisaged for such a system. In this research we examined the optimal battery capacity, operation methods, and economic effects for a system emphasizing an economical merit for the user. We first calculated the hourly amount of photovoltaic generated electricity each month, and used data on average load patterns from actual measurements to calculate battery capacity. Next, taking battery capacity and photovoltaic module capacity/price as parameters, we calculated and evaluated the economic merit for ordinary residences. The result showed that the optimal battery capacity for combination with 3‐ or 5‐kW photovoltaic generation is around 10 kWh, and that a combined system provides a merit even though it entails higher photovoltaic module costs than the use of photovoltaic generation alone. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(4): 20–31, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10302     

Analysis of Wear-Out Degradation of a DFB Laser Using an Optical-Beam-Induced Current Monitor

We investigated the degradation behavior of distributed feedback lasers by employing the optical-beam-induced current measurement technique. We showed that the degradation mechanism is governed by diffused defects at the waveguide other than those in the vicinity of the antireflection facet. In addition, we found that a diffused source is probably generated in the upper InP cladding layer above the grating during the growth of the upper InP cladding layer.     

Threshold reduction of 1.3 mu m GaInAsP/InP surface emitting laser by a maskless circular planar buried heterostructure regrowth

A newly introduced maskless planar buried heterostructure regrowth has substantially improved the regrown heterointerface of a 1.3 mu m GaInAsP/InP circular buried heterostructure surface emitting laser. The threshold current of the 12 mu m phi device was reduced to 2.2 mA at 77 K under CW conditions.<>     

Bone marrow relapse in high-risk pediatric patients with acute lymphoblastic leukemia: a comparison of relapse times and initial clinical features of patients on different protocols. Children''s Cancer and Leukemia Study group (CCLSG)

Alpha adrenergic blocker has become the first choice in the medical treatment of benign prostatic hyperplasia (BPH). The efficacy of alpha adrenergic blocker has been suggested to be related to the prostatic tissue components, and to be ineffective in treating the clinical symptoms caused by BPH in some cases. The efficacy and prostate reduction of an anti-androgenic agent, chlormadinone acetate, combined with alpha adrenergic blocker, tamsulosin hydrochloride, were evaluated using 40-BPH patients insufficiently treated with tamsulosin hydrochloride alone. Fifty mg of chlormadinone acetate and 0.2 mg of tamsulosin hydrochloride were administered orally once a day for 16 weeks to patients with a prostate subjective symptoms score, I-PSS, of greater than 13 or a peak flow rate of less than 12 ml/s, even after the treatment with 0.2 mg of tamsulosin hydrochloride alone for more than four weeks. Total I-PSS decreased significantly after four weeks. The total irritative symptom score did not change for 16 weeks, but the total obstructive symptom score decreased significantly, as did the total I-PSS. In objective data, the estimated volume of both total prostate and the transition zone on transrectal ultrasonogram decreased significantly at the end of the treatment, and the peak flow rate decreased significantly after 12 weeks. These findings suggest that the addition of chlormadinone acetate may be a reasonable alternative in the treatment of BPH patients responding insufficiently to tamsulosin hydrochloride alone, and that combination therapy using chlormadinone acetate and tamsulosin hydrochloride may be useful for BPH patients with serious obstructive symptoms.