Ultrasonic attenuation in the mixed state of a dirty superconductor

Transport coefficients in the mixed state have simple expressions when the response is local. For dirty materials the ultrasonic attenuation is given by the local expression over the whole mixed-state regime because of the Coulomb interaction between the electrons, and responses of the order parameter and magnetic field to the sound wave do not contribute to the attenuation. Computations based on the theory are compared with experiment.On leave of absence from Research Institute of Electrical Communication, Tohoku University, Sendai, Japan.     

Novel linearizer using balanced circulators and its application tomultilevel digital radio systems

A miniaturized RF predistortion linearizer for a GaAs field-effect transistor power amplifier applicable to 256 quadrature-amplitude modulation (QAM) digital microwave systems is presented. This linearizer, which is based upon the cuber linearizer technique, utilizes circulators and a pair of diodes in the distortion generator to obtain high signal component isolation, and in the variable phase shifter to compensate for temperature variations. This allows miniaturization and easy adjustment of the circuit. Results show that a distortion reduction of more than 10 dB is obtained over a 300 MHz bandwidth. It was verified that distortion reduction can be achieved over a temperature range from 0 to 50°C. The fundamental characteristics of the linearizer and its effect on the 256-QAM signal are shown. The results show an improvement of more than 6 dB in the output back-off of the amplifier     

Preparation of CoLaO3 catalyst fine particles by mist decomposition method II effect of additives for the increase of surface area

The mist of a mixed solution of cobalt nitrate, lanthanum nitrate and an additive was produced by a supersonic atomization, and treated successively in the three furnaces of different temperatures to prepare the fine particles of CoLaO₃. The temperatures of the furnaces were adjusted for the evaporation of water, the decomposition of the mixed metal salts, and the crystallization of the mixed oxides, respectively. The spherical particles (ca. 0.7 μm) of a perovskite were prepared. The specific surface area of the particles was increased from 11 to ca. 50 m²/g by the addition of the reagents such as ammonium chloride and a polyvinyl alcohol. The catalytic activities of these samples for the surface combustion of propane were compared.     

2.5 Gbit/s-9720 km, 10 Gbit/s-6480 km transmission in the FSAcommercial system with 90 km spaced optical amplifier repeaters anddispersion-managed cables

The authors report 2.5 and 10 Gbit/s transoceanic distance transmission in a commercial FSA optical amplifier system which has 90 km repeater spacing. The unique fibre dispersion management technique and amplifier passband management scheme used in the system are successfully demonstrated. The SNR improvement achieved with polarisation scrambling is also reported     

Study of fatigue crack growth retardation due to overloads in polymethylmethacrylate

Retardation of the fatigue crack growth after overloading was investigated in conjunction with the craze deformation at the fatigue crack tip in polymethylmethacrylate. The craze deformation was measured by optical interference and analysed numerically with reference to a previously proposed craze model. In the base line loading, the craze stress concentrates at the crack tip with the applied load and, hence, the non-uniform stress distribution is attained at the maximum load. The overload alters this stress distribution. Just after overloading, the crack tip stress does not reach the previous level, even at the same maximum load. The reduced crack tip stress correlates well with the retarded duration after the overload. It is concluded, therefore, that the craze stress reduction at the crack tip is the cause of crack growth retardation.     

Adrenalectomy for treatment of Cushing syndrome: results in 122 patients and long-term follow-up studies

Patients with Cushing syndrome (n = 122) who underwent adrenalectomy from 1957 through 1993 were reviewed for survival and complications. Of the 122 patients, 70 had adrenocortical adenoma, 30 Cushing's disease, 6 primary pigmented nodular adrenocortical disease (PPNAD), 7 other types of primary nodular hyperplasia, 5 adrenocortical carcinoma, and 4 ectopic ACTH syndrome. Sixty-five patients with adrenocortical adenoma are alive, and the survival rate was equal to the age-matched control population, when patients who died of the postoperative complication were excluded. Of the patients with Cushing's disease, 20 are alive; and 10 of 16 patients (63%) who were followed-up and evaluated had skin pigmentation. Four of sixteen patients (25%) developed Nelson's syndrome. Four PPNAD patients and five with other types of nodular hyperplasia are alive. Most of these patients underwent bilateral total adrenalectomy, but some patients remitted after unilateral adrenalectomy. All of five adrenocortical carcinoma patients and four with ectopic ACTH syndrome died within 2 years after operation. The prognosis for patients with adrenocortical adenoma after unilateral adrenalectomy is excellent, though it is important to avoid operative complications. The rapid cure of signs and symptoms of glucocorticoid excess after total adrenalectomy is ensured, and prognosis is satisfactory under careful glucocorticoid replacement, making total adrenalectomy an alternative treatment for Cushing's disease.     

Optimum parameter guidelines for 10 Gbit/s, multi-megametre transmission systems considering the nonlinear effect

The impact of the nonlinear effect, combined with group velocity dispersion, on cascaded amplifier transmission systems is clarified experimentally using a 10 Gbit/s transmission system. Based on the results, the optimum amplifier output power is presented as a function of amplifier spacing 3000 km transmission is feasible at 10 Gbit/s if the spacing is 100 km.<>     

Liver metastases from breast cancer 14 years after radical mastectomy; successful treatment with hepatic arterial infusion chemotherapy and systemic endocrine therapy--a case report

The patient was a 73-year-old woman who was admitted to our hospital for epigastric discomfort and body weight loss. She had undergone radical right mastectomy in March 1982. Ultrasonography and computed tomography revealed multiple tumors in the liver. Three of the tumor markers (CA-125, CA 19-9, and CA 15-3) were positive. US-guided fine needle aspiration biopsy of the liver tumor showed small atypical cells with solid cell nests. Immunohistochemical tests revealed estrogen receptor was positive. We diagnosed the patient as recurrent breast cancer metastatic to liver, 14 years postoperatively. The liver tumors were successfully controlled with the combination of intra-arterial infusion chemotherapy (5-fluorouracil, epirubicin, and mitomycin C) along with systemic endocrine therapy (medroxyprogesterone acetate and fadrozole hydrochloride hydrate).     

DDD pacemaker implantation--cardiac pacemaker tips in the left atrium and ventricle by the left thoracotomy

Recently DDD pacemaker implantation for the children has undergone trials world wide; though regarding the approach, ways and positions of the epicardial lead, a few problems are still remained to be discussed. Now we report 9 cases (5 males, 4 females) of DDD pacemaker implantations by the left anterolateral thoracotomy approach. The 9 patients weighing 6.5 to 33 kg, were aged 11 months to 12 years (mean 6 years) of whom male 5, female 4 with degree of Block; 2 and 7. To all patients the stab-in type epicardial tips were implanted in the left atrium, the screw-in type ventricular epicardial tips were in the left ventricle by the 4th intercostal thoracotomy, and the pacemaker generators were beneath the fascia of the abdominal rectus muscle. We have no sensing and pacing failure, all pacemakers are working in the DDD mode well.