Influence of Spin Fluctuations Upon Heat Capacity of 2D Fermi Liquid Formed on Hectorite

We measured low-temperature heat capacities of two-dimensional Fermi liquid (2D FL) formed on Hectorite down to 15mK. At a coverage where mean atomic distance is comparable to that of bulk ³ He liquid, we found that the temperature dependence deviates considerably from the expected linearity. To account for the deviation we carried through integrals including RPA spin susceptibility for the Stoner-Hubbard(SH) or the Landau's Fermi liquid (LFL) models over the effectively entire, energy-momentum space without imposing the paramagnon approximation or the like. We found numerically that the spin fluctuation develops a T ² correction at T<T* which, at T>T*, is taken over by a Tlog T term where T* is some hundredths of T _F . With these corrections we are able to interprete the data and have determined the parameters for each model consistently at the densities observed.     

Uniform characteristics with low threshold and high efficiency fora single-transverse-mode vertical-cavity surface-emitting laser-typedevice array

Vertical-to-surface transmission electrophotonic devices with a vertical-cavity are described. The individually accessed 12×4 arrays are characterized and demonstrated to have uniform room-temperature continuous-wave operating characteristics for a threshold current of ~2.8±0.15 mA and a slope efficiency of ~0.18±0.012 W/A with a single transverse mode. Both low threshold and high efficiency with 5% and 7% deviation, respectively, are achieved simultaneously. These devices can be used to constructing two-dimensional massively parallel optical interconnections     

Electron transfer reactions of some ferrous complexes of substituted 1,10-phenanthroline

The cyclic voltammograms of ferrous complexes of 5-substituted 1,10-phenanthroline were obtained. The anodic and the cathodic peak potentials shifted toward positive side by substituting electron-withdrawing group for 5-hydrogen in 1,10-phenanthroline. This result was interpreted by that the probability of the transition of electron from d orbital to the empty MO of the ligand was increased by the introduction of electron-withdrawing group, and hence the oxidation of the ferrous complex became more difficult. The oxidized substances of ferrous complex containing this functional group were labile and decomposed chemically.     

Activity determinator for the automatic measurements of the chemical potentials of FeO in metallurgical slags

An automatic system for rapid determinations of the activities of FeO in metallurgical slags has been developed. With this facility, one datum is obtainable within 5 minutes. The facility was applied for the activity measurements in the system CaO + SiO₂ + FeO, while activity data obtained were consistent with those deduced from the phase diagram.     

Duodenal duplication cyst communicating with an accessory pancreatic duct of Santorini

A 16 year-old girl with recurrent attacks of acute pancreatitis and upper gastrointestinal bleeding was found to have an aberrant pancreatic duct communicating with a duodenal duplication cyst and a pancreatic pseudocyst on endoscopic retrograde pancreatography (ERP). A partial gastrectomy combined with resection of the aberrant pancreas was performed. The patient is doing well without any problems 17 years after surgery. ERP was of great value in diagnosing this rare disease. Gastroduodenal duplication cysts communicating with the pancreatic duct are rare; only 21 cases, including our own, have been reported in the English-language literature since 1958.     

Oxidant stress incites spreading of macrophages via extracellular signal-regulated kinases and p38 mitogen-activated protein kinase

Cultured macrophages exhibit spreading in response to external stimuli. It is relevant to in vivo morphologic changes of macrophages during extravasation, migration, and differentiation. The present study was performed to elucidate molecular mechanisms that regulate spreading of macrophages. Redox is a crucial factor that modulates a wide range of cell function. We found that macrophages undergo spreading in response to oxidant stress caused by hydrogen peroxide or an oxidant generating agent menadione. To identify signaling pathways involved, a role of mitogen-activated protein (MAP) kinases was investigated. Western blot analysis showed that treatment of macrophages with menadione rapidly induced phosphorylation of extracellular signal-regulated kinases (ERK1, ERK2) and p38 MAP kinase, but not c-Jun N-terminal kinase (JNK). Pharmacologic inhibition of either ERK or p38 activation blunted the macrophage spreading. Similarly, transfection with dominant-negative mutants of ERKs or a mutant p38 significantly suppressed the oxidant-triggered spreading. ERKs and p38 are known to activate serum response element (SRE) via phosphorylation of the ternary complex factor Elk-1. To further identify downstream events, we focused on a role of SRE. Stimulation of macrophages with menadione induced activation of SRE. Intervention in the SRE activation by a dominant-negative mutant of Elk-1 inhibited the menadione-induced spreading. These results suggest that oxygen radical metabolites, the well-known mediators for tissue injury, incite spreading of macrophages via the MAP kinase-SRE signaling pathways.     

An analysis of creep crack propagation on the basis of the plastic singular stress field

In order to gain an insight into creep crack propagation problems a mechanics approach is presented in this paper on the basis of the plastic singular stress field near a crack tip under the Mode III and I steady-state creep conditions, in combination with a generalized creep damage hypothesis. Closed form equations which predict rates of creep crack propagation are obtained analytically. According to this analysis, it is found that $\text{b}{}_1\text{(n + 1)}$ is the index which characterizes the effect of damage accumulation in front of a crack, where n is the creep exponent and b₁ is the exponent involved in the creep damage hypothesis used in this analysis. The tendency of the predicted crack propagation behaviors is consistent with experimental data available in the literature.     

The potential distribution in local cells on corroding metals

In the galvanic corrosion, the distribution of potential within the electrolyte was calculated for the condition that each local cell is independent and there is no interaction between the local cells. This analysis on the problem extended the Waber's treatment, and the distribution of potential was obtained for each local cell.