Fabrication of Textured Alumina by High-Temperature Deformation

Texture formation via high-temperature deformation in sintered alumina was investigated. Fine-grained, normal-purity-alumina sintered bodies deformed under stresses up to 80 MPa in a temperature range of 1200°–1300°C. Fine, disklike grains formed in the equiaxial fine-grained matrix during high-temperature deformation and aligned unidirectionally via material flow during deformation. Highly textured sintered alumina bodies were obtained via high-temperature deformation and further annealing.     

Removal of cadmium or lead from polluted water by biological amphiphiles

Biological amphiphiles were examined for the removal of Cd²⁺ or Pb²⁺ from polluted water within a pH range from 2.5 to 7.5 at a fixed ratio of amphiphilic concentration to heavy metal concentration (C _A /C _M ) on a molar basis of approximately 11. Tannic acid, among eight amphiphiles, was selected for Cd²⁺ or Pb²⁺ removal because it exerted noticeable improvement within limited pH ranges. In the presence of tannic acid, the removal of Cd²⁺ or Pb²⁺ was investigated as a function of pH ranging from 2.5 to 13 at C _A /C _M ratios from 1.2 to 11. The removal capacity (mass of metal/mass of tannic acid) increased with decreasing C _A /C _M for both Cd²⁺ and Pb²⁺. Removal capacities were 0.084 and 0.154 g/g-tannic acid for Cd²⁺ and Pb²⁺ at pH 6.9 and 4.4, respectively. The maximal removals for Cd²⁺ and Pb²⁺ were 99 and 96%, respectively.     

Prophylactic Therapy with Human Amniotic Fluid Stem Cells Improves Long-Term Cognitive Impairment in Rat Neonatal Sepsis Survivors

A systemic inflammatory response induces multiple organ dysfunction and results in poor long-term neurological outcomes in neonatal sepsis. However, there is no effective therapy for treating or preventing neonatal sepsis besides antibiotics and supportive care. Therefore, a novel strategy to improve neonatal sepsis-related morbidity and mortality is desirable. Recently, we reported that prophylactic therapy with human amniotic stem cells (hAFSCs) improved survival in a rat model of lipopolysaccharide (LPS)-induced neonatal sepsis through immunomodulation. Besides improving the mortality, increasing survival without major morbidities is an important goal of neonatal intensive care for neonatal sepsis. This study investigated long-term neurological outcomes in neonatal sepsis survivors treated with hAFSCs using the LPS-induced neonatal sepsis model in rats. We found that prophylactic therapy with hAFSCs improved spatial awareness and memory-based behavior in neonatal sepsis survivors at adolescence in rats. The treatment suppressed acute reactive gliosis and subsequently reduced astrogliosis in the hippocampal region over a long period of assessment. To the best of our knowledge, this is the first report that proves the concept that hAFSC treatment improves cognitive impairment in neonatal sepsis survivors. We demonstrate the efficacy of hAFSC therapy in improving the mortality and morbidity associated with neonatal sepsis.     

Measurements of the binding of a large protein using a substrate density-controlled DNA chip

The DNA chip that immobilizes DNA oligonucleotides on a solid plate surface is used for many diagnostic applications. For maximizing the detection sensitivity and accuracy, it is important to control the DNA density on a chip surface and establish a convenient method for optimizing the density. Here, the binding of DNA mismatch-binding protein MutS to the DNA substrate on the chip was investigated, which can be applied for high-throughput single-nucleotide polymorphism analysis in a genome. We prepared the DNA chips where the DNA substrate density was changed simply by using a mixed DNA solution. The binding of MutS was significantly influenced by the amount of DNA substrate on the chip as a consequence of steric crowding, and the moderate density that gave the distance between the DNA substrates greater than the size of the protein was appropriate to obtain accurate kinetic parameters. The substrate density-controlled DNA chip prepared using the mixed DNA solution has distinctive advantages for maximizing the detection capability and kinetic analysis of the binding of MutS and probably also other large proteins.     

Effect of location of polymerizable double bond on the polymerization of micelle-forming monomers

Summary The polymerizability of micelle-forming quaternary ammonium monomers, which were derived from a methacrylic ester and styrene, carrying a polymerizable double bond close to the head group (Type H) or at the alkyl chain end (Type T) including a new monomer, 5-(p-vinylphenyl)pentyltrimethylammonium bromide, has been investigated above their critical micelle concentrations in water. The results are explained on the basis of the structure of the obtained polymers as well as the micelle structure of the monomers in water. The Type H monomers were able to thermally polymerize, while the Type T monomers could not.     

Quality of hearing preservation in acoustic neuroma surgery

OBJECTIVE: This study aimed to investigate the factors affecting the quality of postoperative hearing in acoustic neuroma. STUDY DESIGN: The study was designed as a retrospective case review. SETTING: The study was performed at the Department of Otolaryngology, School of Medicine, Keio University, Tokyo, Japan. PATIENTS: The subjects were 94 patients with unilateral acoustic neuroma. INTERVENTION: Hearing preservation surgery was performed in the subjects via the extended cranial fossa approach or the middle cranial fossa approach. MAIN OUTCOME MEASURES: The outcome measures included patient's age and gender, hearing level, speech discrimination score, tumor size, and surgical approach. The relationship between the qualities of preoperative and postoperative hearing and the long-term prognosis of preserved hearing also was investigated. RESULTS: In 94 subjects, there were 47 patients whose hearing was preserved (HP group) and 47 patients whose hearing was not preserved (non-HP group). Overall, hearing preservation rate was 50%. There were no significant differences in age, gender, and tumor size between the two groups. The hearing preservation rate was significantly higher in patients with an intracanalicular tumor than that with a larger tumor. The better the preoperative quality of hearing was, the higher the postoperative one. Although the preserved hearing deteriorated after surgery in 4 patients, no significant hearing deterioration was observed in the other 43 patients. CONCLUSIONS: The results of this study indicated that the diagnosis for acoustic neuroma in the early stage with serviceable hearing is the most important to improve the quality of postoperative hearing.     

New criteria for wind effects on pedestrians

Experiments concerned with wind effects on pedestrians are described. The experiments consists of three parts. In Part I, walking tests were conducted in a large wind tunnel. In Part II, walking tests were held in a precinct at the base of a high-rise building. Part III again consisted of observation of pedestrians in a precinct at the base of a high-rise building. In Parts I and II, 5 to 10 persons were used as subjects and movie records of their footsteps were analysed. In Part III, movie records taken by video camera of over 2000 pedestrians were analysed as to footstep-irregularity and body-balance.Based on these three-part experiments, the following criteria are proposed for evaluating wind effects on pedestrians:

$\text{u<}\text{m s}{}^{\mathrm{?1}}\text{no effect}\text{5<}\text{u<10}\text{some effect}\text{10<}\text{u<15}\text{serious effect}\text{15<}\text{very serious effect}$

where u is the instantaneous wind speed averaged over 3 s.These criteria are the same as or a little more severe than those proposed by Hunt et al. [6] and considerably more severe than others.     

Strength of Silicon Nitride after Thermal Shock

A water-quenching technique was used to evaluate the thermal-shock strength behavior of silicon nitride (Si₃N₄) ceramics in an air atmosphere. When the tensile surface was shielded from air during the heating and soaking process, the quenched specimens showed a gradual decrease in strength at temperatures above 600°C. However, the specimens with the air-exposed surface exhibited a ∼16% and ∼29% increase in strength after quenching from 800° and 1000°C, respectively. This is because of the occurrence of surface oxidation, which may cause the healing of surface cracks and the generation of surface compressive stresses. As a result, some preoxidation of Si₃N₄ components before exposure to a thermal-shock environment is recommended in practical applications.