Influence of fillers on hydrogen penetration properties and blister fracture of rubber composites for O-ring exposed to high-pressure hydrogen gas

Ethylene–propylene rubber (EPDM) and nitrile–butadiene rubber (NBR) composites having carbon black, silica, and no fillers were exposed to hydrogen gas at a maximum pressure of 10 MPa; then, blister tests and the measurement of hydrogen content were conducted. The hydrogen contents of the composites were proportional to the hydrogen pressure, i.e., the behavior of their hydrogen contents follows Henry's law. This implies that hydrogen penetrates into the composite as a hydrogen molecule. The addition of carbon black raised the hydrogen content of the composite, while the addition of silica did not. Based on observations, the blister damages of composites with silica were less pronounced, irrespective of the hydrogen pressures. This may be attributed to their lower hydrogen content and relatively better tensile properties than the others.     

Phase transition and proton transport characteristics in CsH2PO4/SiO2 composites

The stabilization of superprotonic phase in neat CsH₂PO₄ and CsH₂PO₄/SiO₂ composites as well as the anomalous phase transformation with a large hysteresis was investigated through proton conductivity, thermal analysis and Raman spectroscopy. The reversibility of the transition to the superprotonic phase and the phase transformation between monoclinic phase and cubic phase in neat CsH₂PO₄ at around T_c = 230 °C was confirmed under humidified and sealed conditions. In CsH₂PO₄/SiO₂ composites, a large asymmetric thermal hysteresis in the conductivity appeared, i.e. significant supercooling in the superprotonic phase was induced in silica matrices. A differential thermal analysis revealed that the temperature of a reverse transition from the cubic phase (superprotonic phase) to the monoclinic phase decreased in the composites. This effect became significant with an increase in silica volume fraction. The stabilization of superprotonic phase (cubic phase) in the composites will be induced by shear elastic forces at the interface between CsH₂PO₄ and silica particles. The main origin of the anomalous asymmetric thermal hysteresis in proton conductivity is the phase stability arising from the shear elastic forces and a proton-conducting network in silica matrices.     

Molecular Classification and Overcoming Therapy Resistance for Acute Myeloid Leukemia with Adverse Genetic Factors

The European LeukemiaNet (ELN) criteria define the adverse genetic factors of acute myeloid leukemia (AML). AML with adverse genetic factors uniformly shows resistance to standard chemotherapy and is associated with poor prognosis. Here, we focus on the biological background and real-world etiology of these adverse genetic factors and then describe a strategy to overcome the clinical disadvantages in terms of targeting pivotal molecular mechanisms. Different adverse genetic factors often rely on common pathways. KMT2A rearrangement, DEK-NUP214 fusion, and NPM1 mutation are associated with the upregulation of HOX genes. The dominant tyrosine kinase activity of the mutant FLT3 or BCR-ABL1 fusion proteins is transduced by the AKT-mTOR, MAPK-ERK, and STAT5 pathways. Concurrent mutations of ASXL1 and RUNX1 are associated with activated AKT. Both TP53 mutation and mis-expressed MECOM are related to impaired apoptosis. Clinical data suggest that adverse genetic factors can be found in at least one in eight AML patients and appear to accumulate in relapsed/refractory cases. TP53 mutation is associated with particularly poor prognosis. Molecular-targeted therapies focusing on specific genomic abnormalities, such as FLT3, KMT2A, and TP53, have been developed and have demonstrated promising results.     

The permselective coefficient of inorganic ions on reverse osmosis membrane

Although many investigations on the rejection of inorganic ions in reverse osmosis were carried out for single-solute systems, their measurements could not be compared exactly with each other because of the change of the membrane property with time. In this paper, the permselective coefficient in reverse osmosis was defined similarly to electrodialysis, and those of various ions for mixed-solute systems were measured. From the results, an approximately linear relationship exists between a logarithm of the permselective coefficient of each ion and the charge-to-radius ratio. The influence of experimental conditions on the permselective coefficient was studied.     

Sclerosing peritonitis associated with luteinized thecoma of the ovary

A unique case of bilateral luteinized thecomas of the ovary associated with sclerosing peritonitis is reported and the clinical and pathological features of this and previously reported cases are reviewed. The patient, 52 years of age, presented with abdominal distension and diarrhea. Pelvic imaging studies revealed bilateral ovarian tumors with ascites. Total abdominal hysterectomy and bilateral salpingo-oophorectomy with adhesiotomy of the small bowel were performed. Histologically, the ovarian tumor was composed of closely packed spindle to round-shaped cells, and within the spindle cell population, lutein-like cells were scattered singly or in clusters. Mitotic counts of spindle cells revealed 12 mitotic figures (MF) per 10 high-power fields (HPF) in one part of the left ovarian tumor, but other areas of the tumor showed less than 3 MF/10 HPF on average. The lesion from the resected small bowel showed prominent fibrosis, confined to the serosa with no evidence of metastasis from the ovarian tumor. The patient has undergone adhesiotomy with partial resection of the small bowel seven times since the first laparotomy because of the recurrent small bowel obstruction. The patient has survived with complications due to short bowel syndrome for 7 years after the initial surgery and so far no recurrence or metastasis of the ovarian tumor has been identified. The case reported here also supports the idea that luteinized thecoma of the ovary associated with sclerosing peritonitis may be a distinct clinicopathologic entity, in terms of the unique association and of the unique features of thecoma; that is, bilateral, hormonally inactive and apparently benign in spite of its highly mitotic activity. Additional attention should be paid to the patient's quality of life, which is often degraded by peritoneal fibrosis and small bowel obstruction.     

Effect of metal ion location in reaction medium on formation process and structure of PtCu–CuO nanoparticles supported on carbon and γ-Fe2O3

The process of nanoparticle formation by radiochemical synthesis in a heterogeneous system has been investigated considering the effects of the metal ion location in the reaction medium. PtCu nanoparticles supported on carbon and γ-Fe₂O₃ were synthesized using a high-energy electron beam. The metal ions in the precursor were categorized as those dissolved in solution, adsorbed on support, and precipitated. The ratio of metal ions in the solution was varied prior to the electron beam irradiation and its effects on the synthesized particle structures were examined. The nanoparticles were characterized by inductively coupled plasma-atomic emission spectrometry, transmission electron microscopy, X-ray diffraction, and X-ray absorption spectroscopy. A PtCu alloy and CuO were immobilized on the support in all the samples. The PtCu alloy nanoparticle composition depended on the Cu ion content in the solution. The nanoparticle formation mechanism could be explained using the obtained results. Metal ions present in the solution resulted in formation of the alloy. The adsorbed ions also contributed to the alloy formation by desorbing from the support when irradiated. On the other hand, alloy formation with Pt from the precipitated Cu ions was found to be difficult.     

Electronic Structure of Corannulene Monoanion: A Comparative Study with the Neutral and Tetraanionic States

Electronic structure of monoanionic corannulene, C₂₀H^-₁₀, has been studied comparing with those of C₂₀H₁₀ and C₂₀H^4-₁₀ based on the ab initio molecular orbital calculation at the HF/3-21G level. The difference in geometries and electronic structures among these three corannulene systems and the strength of Jahn-Teller distortion appearing in C₂₀H^-₁₀ are discussed.