Thermodynamics of sulfur in the BaO-MnO-SiO2 flux system

The sulfide capacity of the molten BaO-MnO-SiO₂ system was determined by measuring the sulfur partition ratio between the oxide and an Ag-S alloy in a controlled CO-CO₂-Ar gas mixture at 1573 K for two purposes. One is to develop highly basic fluxes which can extensively desulfurize manganese-based alloys, and the other is to examine the effect of BaO addition on thermodynamic properties of sulfur in the MnO-SiO₂ melts from which MnS precipitates functioning as the nucleus for subsequent γ -α transformation of steel. The sulfide capacity of the BaO-MnO-SiO₂ system strongly depends on the composition, and MnO has been found to enhance sulfide capacity to a greater extent than BaO at less basic compositions.     

PREPARATIVE SEPARATION OF PROTEINS BY GRADIENT- AND STEPWISE-ELUTION CHROMATOGRAPHY: ZONE-SHARPENING EFFECT

A method is developed for predicting the zone-sharpening effect in linear gradient- and stepwise-elution chromatography of proteins. Numerical calculations have shown that the elution curve by different models are almost the same when the values of zone spreading parameters in the model are chosen so that the values of the number of the theoretical plates are equal. A good correlationship curve is established on the basis of the numerical calculations, from which the degree of the zone-sharpening can be easily predicted with a single dimensionless parameter.

When the modulator concentration is very high (the desorption is complete), the stepwise-elution chromatography can be regarded as the gradient elution with steep-slope of the gradient. The experimental stepwise elution cation-exchange chromatography of basic proteins from egg white has shown that the purity, the recovery and the concentration factor of the recovered fraction are very high.     

Auxiliary resonant commutated pole inverter using two internalvoltage-points of DC source

This paper presents a new auxiliary resonant commutated pole inverter that has series-connected batteries as the DC source. This inverter has two main switches and two auxiliary switches, and of all these devices achieve soft switching. The resonant operations are employed only during the commutating intervals; therefore, pulsewidth modulation (PWM) can be applied to the circuit. This circuit has the feature of using two internal voltage points of the DC source. Consequently, the circuit has the advantages of stability, simplicity in control, and high efficiency. The principle of the circuit operation and the experimental results are described in this paper     

Perineurial malignant peripheral nerve sheath tumor (MPNST): a clinicopathologic, immunohistochemical, and ultrastructural study of seven cases

Most malignant peripheral nerve sheath tumors (MPNST) are schwannian in nature. The pathologic features of MPNST with perineurial cell differentiation remain to be characterized. To determine the clinicopathologic, immunohistochemical, and ultrastructural characteristics of perineurial MPNST, 121 MPNST from the Mayo Clinic Tissue Registry were examined. Of these 23 spindle cell tumors with long processes disposed in whorls or storiform patterns, features typical of perineurioma, were studied. On the basis of immunohistochemistry (epithelial membrane antigen+/S-100-), 5 perineurial MPNST were identified among 23 tumors selected. These and two previously characterized perineurial MPNST are the subject of this study. None of seven tumors was associated with NF-1. Patients included five males and two females ranging in age from 11 to 83 years (mean, 45.7 years). The tumors measured 1.5 to 30 cm (mean, 9.1 cm) and arose in the extremities (two), trunk (two), face (one), mediastinum (one), and retroperitoneum (one). Only one tumor was nerve associated (phrenic nerve). All tumors were surgically removed. No encapsulation or neurofibroma components were noted. Necrosis was seen in three lesions. Four tumors were classified as high-grade malignant and three as low grade. Mitotic indices varied from 1 to 85/10 high-power fields (median, 16). Immunoreactivities included epithelial membrane antigen (100%), vimentin (100%), Leu-7 (57%), and CD34 (14%). Stains for S-100 protein, muscle markers, and cytokeratin were nonreactive. Ultrastructurally, perineurial-like cells were noted in three tumors and cells intermediate between perineurial and Schwann cells in one. Four tumors recurred and two metastasized; no deaths of disease were noted at follow-ups of 28 to 98 months (mean, 66.9). In conclusion, 4% of MPNST show perineurial cell differentiation. An NF-1 association has yet to be described. Nerve involvement is infrequent. Their immunophenotype (epithelial membrane antigen+/S-100-) frequently indicates ultrastructural perineurial differentiation. The prognosis of perineural MPNST appears to be more favorable than that of conventional MPNST.     

Design and performance of clock recovery GaAs ICs for high-speedoptical communication systems

Design and performance of clock-recovery GaAs ICs are presented. Four kinds of ICs were developed: a limiting amplifier, a tuning amplifier, a rectifier, and a differentiator. The cascaded limiting amplifier together with a tuning amplifier achieved a 58-dB gain and a 10-degree phase deviation with 20-dB input dynamic range at 10 GHz. A clock-recovery circuit successfully extracts a low-jitter 10-GHz clock signal of 1-dBm constant power from 10-Gb/s NRZ pseudorandom bit streams using a pulse pattern generator     

Admittance and Impedance Representations of Friction Based on Implicit Euler Integration

Modeling of friction force is cumbersome because of its discontinuity at zero velocity. This paper presents a set of discrete-time friction models for the purpose of haptic rendering and virtual environment construction. These models allow friction to be treated as an admittance-type or impedance-type element of a virtual environment. They are derived from implicit Euler integration of Coulomb-like discontinuous friction and linear mass-spring-damper dynamics, and have closed-form expressions. They include rate-dependent friction laws, and their extension to multidimensional cases is easy in most practical cases. The validity of the models is demonstrated through numerical examples and implementation experiments     

Immunohistochemical overexpression of p16 protein associated with intact retinoblastoma protein expression in cervical cancer and cervical intraepithelial neoplasia

A 35-year-old man with non-Hodgkin's lymphoma (NHL) (follicular small cleaved, B cell, stage IVB) received double myeloablative chemotherapy with syngeneic peripheral blood stem cell transplantation (PBSCT). Although platelet recovery was delayed until day 29 after the second transplantation, thereafter trilineage hematopoietic reconstitution was achieved. The evaluation after PBSCT did not detect any residual tumor. The patient was in good health until day 138, when his platelet count suddenly began falling; on day 150, it had fallen to 1.5 x 10(4)/microliter, and the patient was re-admitted for treatment. The bone marrow was normocellular with a normal count and megakaryocyte structure. Other examinations, including serological tests and computed tomography of the neck, chest, abdomen, and retroperitoneum, did not indicate a recurrence of NHL or reveal the cause of thrombocytopenia. The patient's platelet-associated IgG (PAIgG) level was at 70.9 ng/10(7) platelets (normal range: 9-25 ng/10(7) platelets); a diagnosis of thrombocytopenia due to an autoimmune mechanism such as idiopathic thrombocytopenic purpura (ITP) was made. Prednisolone therapy increased the platelet count and reduced the PAIgG level. Thrombocytopenia with an ITP-like mechanism rarely occurs more than 100 days after autologous or syngeneic stem cell transplantation, and should be taken into consideration as a late complication of PBSCT.