Intussusception caused by a carcinoma of the cecum during pregnancy: report of a case and review of the literature

Respiratory infections are the most common infection in children. They differ remarkably according to age, bacteria and viruses. Therefore a careful history of outbreak, age, former infections, involvement of surroundings, symptoms, etc are essential. The present study included 50 children, aged between 0.3 and 12 yrs, all treated ambulatorily. 21 received brodimoprim (B) and 29 erythromycin (E). Indications were: tonsillitis, bronchitis, otitis media, sinusitis and scarlet fever. Dosages were: B was given 10 mg/kg body weight (b.w.) initially followed by 5 mg/kg b.w., once-a-day. The duration of treatment varied between 4 and 14 days (mean 8.3 days). E was given 30.50 mg/kg b.w. 3 times per day; duration 4 to 14 days (mean 8.6 days). Overall results were: in group B:12 cures, 5 improvements, 3 failures; 1 not assessable. In group E: 20 cures, 8 improvements, 1 failure. Side effects: in group B: vomiting (1), skin reaction (2), discontinuation (2); in group E: skin reaction (1), diarrhea (5), diarrhea+vomiting (1); discontinuation (2). The differences in efficacy and tolerability in the two groups are not statistically significant. The improved compliance with a single versus t.i.d. dosages has to be taken into account.     

The blocking barrier effect on aluminum electromigration due totitanium layers in multilayered interconnects of LSI's

Experimental evidence of an increase in the resistance of a cathode-side metal line without any void generation is presented for a multilayered metal structure terminated by via-holes during electromigration tests. This resistance increase is reversed to the initial value by high temperature storage after electromigration testing. The increase in the resistance of multilayered metal structures is attributed to the vacancy accumulation in the cathode side due to the blocking barrier effect of the refractory metal layer in the via-hole     

Deformation of NiO single crystals below room temperature: dislocation configurations

NiO single crystals prepared by two crystal growth techniques (zone melting in an arc-image furnace and Verneuil crystallization have been deformed by compression along 001 at temperatures as low as 4.2 K, and the dislocation substructure observed by transmission electron microscopy. The Peierls mechanism has been suggested as the mechanism controlling the mechanical behaviour at the lower temperatures. The dislocations generated at cavities found in the zone-melted crystals may be responsible for the increase of the flow stress of these crystals compared with the Verneuil ones.     

Temperature Dependence of KIC for High-Pressure Hot-Pressed Si3N4 Without Additives

Temperature dependence of K_IC values for Si₃N₄ bodies sintered at high pressures without additives was studied from room temperature to 1400°C. Little change in K_K was found in this range.     

Temperature Dependence of Young's Modulus and Internal Friction in Alumina, Silicon Nitride, and Partially Stabilized Zirconia Ceramics

The temperature dependence of Young's modulus and internal friction (Q⁻¹)in alumina, silicon nitride, and partially stabilized zirconia (Y-PSZ) ceramics was studied. Little change in Q⁻¹ was found for alumina, whereas Q⁻¹ for silicon nitride ceramics increased above 700°C. The Q⁻¹ of Y-PSZ increased markedly with increasing temperature up to a peak at ∼200°C.     

A polar coordinate integration scheme with a hierachical correction procedure to improve numerical accuracy on the boundary element method

In order to calculate accurate physical values of interior region by the boundary element method, a new approach is proposed to singular kernel integration which is applicable to general isoparametric elements and never fails, no matter where the internal point under consideration may be located. The integration scheme consists of two parts.First, the singular kernel functions are assumed to be reciprocal of the distance types. Then the present scheme describes on the quadrate boundary element. The element is subdivided into four triangular regions for which Gauss-Legendre numerical quadrature is applied.Secondly, a method is proposed to reduce residual errors in the application of the above mentioned numerical scheme. The boundary integrals to calculate interior physical values are expressed formally with exact and numerical error terms, and boundary values in error terms are expanded by a Taylor series around the interior point. To evaluate the coefficient of each derivative in the series, a boundary integral form of an identity with respect to a vector from the interior point to the boundary surface is derived. Error resulting from numerical integration of the identity is found to coincide with the coefficient of the derivative in the Taylor series. Thus, the correction factor for numerical errors is obtained.The present scheme was verified to be quite effective such that both the numerical error and CPU time became 1/100 less than those by the double exponential quadrature. Moreover, the present numerical scheme is applicable to general curved elements.     

Thermomechanical fatigue behavior of the third-generation,single-crystal superalloy TMS-75: Deformation structure

The deformation structure after the out-of-phase thermomechanical fatigue (OP TMF) of the single-crystal (SC), Ni-based superalloy TMS-75 has been studied. Mechanical experiments were performed at temperatures between 400 °C and 900 °C under different total strain ranges with varying hold times in the compression stage. The lives of TMF for samples with hold times of 10 and 60 minutes dropped drastically by one order of magnitude as compared with those without it. Different structures developed during TMF were correlated to the difference in mechanical behavior for the two cases. The dislocations in the γ phase and the stacking faults (SFs) in the γ′ phase were quantitatively analyzed by transmission electron microscopy (TEM). This work verified that shearing of the γ′ precipitates occurred with a single-dislocation mechanism rather than a dislocation-reaction mechanism. The implications of this work on the design of superalloys are presented.     

Spin-vortex Superconductivity

We present a theory of superconductivity based on the theoretical prediction that a macroscopic persistent current is generated by spin-vortices. It explains the origin of the phase variable θ that is canonical conjugate to the superfluid density as a Berry phase arising from the spin-vortex formation. This superconductivity does not require Cooper-pairs as charge carriers, thus, is not directly related to the standard theory based on the BCS one; however, it exhibits the flux quantization in the unit Φ ₀=hc/2|e|, where h is Planck’s constant, c the speed of light, and e the electron charge; and the AC Josephson frequency, f _J=2|e|V/h, where V is the voltage of the battery connected to the superconductor–insulator–superconductor junction. In due course, it is found that the standard derivation of the AC Josephson frequency misses a term arising from the flow of particles through the leads connected to the junction. If this contribution is included, the observed f _J indicates that the phase θ is a variable conjugate to the number density of charge e carriers instead of the currently accepted charge 2e carriers. We propose an experiment that discriminates whether it is e or 2e. If the above claim is verified, it means that the BCS theory cannot predict whether a particular compound is a superconductor or not since it does not explain the origin of θ. A connection between the present mechanism and the BCS mechanism is discussed; the fact that the BCS theory gives an excellent estimate of T _c is attributed to the fact that it predicts the temperature at which spin-vortices become long-lived due to the energy gap formation; since the stabilization by the electron-pair formation is compatible with the present mechanism, asymmetries observed in the even and odd number of electron systems are preserved. The most notable difference is that the persistent current generation is formulated in a strictly particle-number-conserving manner. Thus, it does not violate the superselection rule for the total charge.     

FM/PWM control scheme in class DE inverter

This paper presents a new control scheme for a Class DE inverter, that is, frequency modulation/pulsewidth modulation (FM/PWM) control. Further, the FM/PWM controlled Class DE inverter is analyzed and we clarify performance characteristics. Since the FM/PWM controlled inverter has two control parameters, namely, the switching frequency and the switch-on duty ratio, it has one more degree of freedom for the control than the inverter with the conventional control scheme. The increased degree of freedom is used to minimize the switching losses. Therefore, it is possible to control the output power with high power-conversion efficiency for wide-range control. Carrying out the circuit experiments, we confirm that the experimental results agree well with the theoretical predictions quantitatively. For example, the proposed controlled inverter can control the output voltage from 56% to 191% of the optimum one, which is designed for 1.8 W at 1.0 MHz, with maintaining over 90% power-conversion efficiency.