New approach to environmentally benign epoxidation: the solid-phase-system using urea–H2O2 and recyclable dodecatungstate on apatite

On the basis of new concept using a solid disperse phase we have developed an efficient catalytic solid-phase-system for epoxidations of alkenes using urea–hydrogen peroxide (urea–H₂O₂) complex and cetylpyridinium dodecatungstate ((CetylPy)₁₀[H₂W₁₂O₄₂]) catalyst on fluorapatite (FAp). The recovered solid catalyst phase was reused to keep the catalytic activity after several times. In the conceptual idea it is a key point that in situ solid-phase-activation of the catalyst with urea–H₂O₂ proceeds to form microcrystals of the active species dispersed on the solid phase. The dispersion of the catalyst on FAp in the case of tungstic acid (H₂WO₄) was suggested by EPMA analysis. We proposed the peroxo type of species keeping the parent polyoxometalate framework as novel active species from FT-IR spectroscopic studies. FAp phase plays important roles of dispersing the active species on its surface to have high catalytic activity and of stabilizing the active species to lead to high reusability.     

Multivariate analysis of the associations between laboratory data and clinical features among patients with infectious mononucleosis syndrome

Infectious mononucleosis (IM) syndrome is typically caused by EBV, but also by drugs and other organisms such as CMV and HBV. It demonstrates a wide range of clinical and laboratory characteristics, presumably depending on the age of onset. However, associations of laboratory abnormalities with the clinical features have not been well documented. We evaluated here, the associations among patients with IM syndrome using of multiple regression (MR) and multiple logistic regression (MLR) analyses. We examined 90 (40 males, 50 females) patients, who were admitted to our hospital with IM syndrome. The diagnostic criteria were fever and presence of atypical lymphocytes (> 5% of the WBC or the count including monocytes > 5000/microliter), and at least 3 of 7 clinical features: tonsillitis, lymphadenopathy, skin rash, hepato-, spleno-megaly, hepatic dysfunction. The diagnosis of EBV was serologically confirmed in 41 cases. MR revealed that the higher age group tended to have lower platelet counts, and that lower platelet counts were associated with higher ALT levels. In addition, MLR revealed that patients with skin rash tended not to have splenomegaly. The frequency of splenomegaly was not related to age, contrary to the findings of previous reports. These findings are useful to differentiate IM syndrome based on laboratory data.     

Phase separation behavior and morphology development of phenolic resin/PMMA/hexamethylenetetrarnine blends

Summary In order to obtain materials with nanopores which will be applicable for many fields, the structures of the cured blends of phenolic resin (PhN), poly(methyl methacrylate) (PMMA) and curing agent were studied. After PMMA was extracted from cured blends, the structures of cured phenolic resins were observed with SEM. As a results, it was found that nanosized continuous pore structures were formed in extremely wide composition region if curing temperature was high.     

A comment on pure-strategy Nash equilibria in competitive diffusion games

In [N. Alon, M. Feldman, A.D. Procaccia, M. Tennenholtz, A note on competitive diffusion through social networks, Inform. Process. Lett. 110 (2010) 221–225], the authors introduced a game-theoretic model of diffusion process through a network. They showed a relation between the diameter of a given network and existence of pure Nash equilibria in the game. Theorem 1 of their paper says that a pure Nash equilibrium exists if the diameter is at most two. However, we have an example which does not admit a pure Nash equilibrium even if the diameter is two. Hence we correct the statement of Theorem 1 of their paper.     

Formation of Tetravalent Fe Ions in LaFeO3 Perovskite Through Mechanochemical Modification by Ball Milling

Mechanochemical modification of previously synthesized LaFeO₃ perovskite‐type oxide by a high‐energy ball milling was investigated to introduce Fe⁴⁺ ions or transform some Fe³⁺ into Fe⁴⁺ in LaFeO₃. X‐ray absorption fine structure studies revealed that the formation of Fe⁴⁺ ions into LaFeO₃ perovskite has been achieved at first time by ball milling at room temperature without any additives or replacement of La³⁺ ions by some divalent cations. The structural model of Fe⁴⁺ containing LaFeO₃ could be described as with a modified perovskite having equal amounts of La and Fe vacancies, which is supported by a good correlation between the results of Fe K‐edge XANES spectra and O₂‐TPD. The synthesis of Fe⁴⁺‐containing LaFeO₃ perovskite by ball milling was able to produce the O₂ adsorption capacity of nonsubstituted perovskite‐type oxide.     

Accuracy of the difference scheme of solving the eigenvalue problem for the Laplacian

The finite-difference approximation of the eigenvalue problem with the Dirichlet boundary conditions for the Laplacian in a two-dimensional domain of complex form is analyzed for accuracy and the error of eigenfunctions from the class W₂²( W) W_2^2\left( \Omega \right) in the mesh norm of W₂¹( w) W_2^1\left( \omega \right) is estimated.     

Some ultrastructural effects of testosterone and insulin on the ventral prostate of rats in organ culture

The fine structure of the secretory epithelial cells of rat's ventral prostate has been studied following organ culture. Culturing with either testosterone or insulin alone, and with the two hormones combined, were carried out to investigate how insulin modifies the action of testosterone on the maintenance of cellular integrity. After 4 days in hormone-free culture, the secretory epithelial cells showed signs of cellular atrophy and regression, involving loss of the apical microvilli, absence of the apical secretory vacuoles, atrophy of the Golgi apparatus, decrease in rough endoplasmic reticulum and the appearance of autophagic vacuoles. The presence in the medium of either testosterone or insulin alone, or combined, prevented cellular atrophy and regression. The best maintenance of cellular integrity was obtained in a culture containing both hormones. The effects of insulin was approximately equivalent to those of testosterone in the maintenance of cellular integrity.     

Formation mechanism of monodispersed spherical core-shell ceria/polymer hybrid nanoparticles

Very unique core-shell ceria (cerium oxide)/polymer hybrid nanoparticles that have monodispersed spherical structures and are easily dispersed in water or alcohol without the need for a dispersant were reported recently. The formation mechanism of the unique nanoparticles, however, was not clear. In order to clarify the formation mechanism, these nanoparticles were prepared using a polyol method (reflux heating) under varied conditions of temperature, time, and concentration and molecular weight of added polymer (poly(vinylpyrrolidone)). The size of the resultant nanoparticles was strongly and complicatedly dependent on the set temperature used during reflux heating and the poly(vinylpyrrolidone) molecular weight. Furthermore, the size of the nanoparticles increased by a 2-step process as the reflux heating time increased. The IR spectral changes with increasing reflux time indicated the increase in the number of cross-linked polymers in the shell. From these results, the formation mechanism was discussed and proposed.     

Protective effect of amiloride against reperfusion damage as evidenced by inhibition of accumulation of free fatty acids in working rat hearts

To examine whether amiloride protects against ischemia-induced or reperfusion-induced damage to the heart, mechanical and metabolic studies were performed in the isolated, working rat heart. Ischemia decreased both mechanical function and the tissue levels of high-energy phosphates and increased the tissue levels of free fatty acids (FFAs). Reperfusion restored the levels of high-energy phosphates but further increased FFA accumulation. For this reason, accumulation of FFAs was used as an indicator of both ischemia-induced and reperfusion-induced damage. Drugs were added to the perfusion solution 5 min before ischemia until the end of ischemia (pre) or until 10 min after reperfusion (pre + post). Diltiazem (1 or 5 mumol/L pre) decreased the mechanical function of the non-ischemic heart and attenuated both ischemia-induced and reperfusion-induced accumulation of FFAs. Amiloride (50 mumol/L pre) did not affect the mechanical function of the non-ischemic heart or attenuate ischemia-induced or reperfusion-induced FFA accumulation effectively. However, amiloride (50 mumol/L pre + post) did markedly attenuate the reperfusion-induced accumulation of FFAs. In conclusion, diltiazem attenuates both ischemia-induced and reperfusion-induced myocardial damage, probably through its energy-sparing effect as a result of a decrease in mechanical function before ischemia. In contrast, amiloride attenuates only the reperfusion-induced myocardial damage through mechanisms other than the energy-sparing effect.     

A New Silicon Sensor for Hot Metal Measurements

In the present study, an electrochemical sensor has been designed for the direct measurement of silicon content in hot metal. The sensor represents a galvanic silicon concentration cell of the type Ni_sat—Si(1) II silicate electrolyte (1) II Fe—C—Si(1) The tubular silica-glass sensor can be immediately immersed into the metal bath at a response time of 30 to 60 s. A reproducible EMF vs. wt.% Si relationship was obtained for measurements in carbon-saturated Fe—C—Si melts at 1400°C and Si contents from 0.05 to 1.8 wt.%. This relationship is nearly identical with the cell function calculated from thermodynamic data.