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Polystyrene beads (PS beads) with narrow size distribution were synthesized, and their diameter was controlled from 1.2 to 5 µm by varying the injection rate of a styrene solution containing initiator and the concentration of reactant, such as initiator and capping material. The diameter of the PS beads increased with increasing in the injection rates and the initiator concentration or decreasing the capping material concentration. Then, we used the PS beads as building block, and organized them into a hexagonally close-packed monolayer on substrate with template-assisted manual assembly. We showed perfect hexagonally close-packed organization of the PS beads with various sizes in large-scale area. And we demonstrated the superiority of the dry manual assembly over the wet self-assembly in terms of simplicity, speed, perfect ordering, and large scale. [ABSTRACT FROM AUTHOR]

In order to obtain optimum growth conditions for desired thickness and more effective silicon feedstock usage, effects of processing parameters such as preheated substrate temperatures, time intervals, moving velocity of substrates, and Ar gas blowing rates on silicon ribbon thickness were investigated in the horizontal growth process. Most of the parameters strongly affected in the control of ribbon thickness with columnar grain structure depended on the solidification rate. The thickness of the silicon ribbon decreased with an increasing substrate temperature, decreasing time interval, and increasing moving velocity of the substrate. However, the blowing of Ar gas onto a liquid layer existing on the surface of solidified ribbon contributed to achieving smooth surface roughness but did not closely affect the change of ribbon thickness in the case of a blowing rate of ≥ 0.65 Nm³/h because the thickness of the solidified layer was already determined by the exit height of the reservoir. [ABSTRACT FROM AUTHOR]

A nanostructured SiC was successfully obtained through the decomposition of Al4SiC4 additive during spark plasma sintering at the lowest temperature so far published under the pressing condition of below 121 MPa. The specimen had a relative density of 95% after sintering at 1450°C, and nearly full densification with a grain size of around 70 nm was achieved at 1500°C. Heavy Al segregation occurred at the grain boundaries, which caused the low-temperature sintering most presumably by promoting grain-boundary diffusion. [ABSTRACT FROM AUTHOR]

Background. Hepatocyte growth factor (HGF) can promote proliferation, invasion, and angiogenesis in various tumor cells. However, the prognosis according to expression of HGF/c-Met has not been reported in patients with squamous cell carcinoma of the oral tongue (SCCOT). Methods. Tumors from 61 patients with SCCOT were evaluated for the expression of HGF and c-Met by immunohistochemistry. For Western blot, we used fresh normal and cancer tissues from 3 patients with SCCOT. Results. The positive rates of HGF and c-Met immunostaining in SCCOT were 57.3% and 54.1%, respectively. The c-Met staining was significantly correlated with lymph node metastasis (p = .005), tumor classification (p = .004), and recurrence (p = .018). Survival was significantly affected in patients with positive c-Met expression (p = .003). HGF and c-Met were strongly expressed in cancer tissues on Western blot. Conclusion. The c-Met expression may play an important role in the progression and the survival outcome of patients with SCCOT. [ABSTRACT FROM AUTHOR]

The processing parameters for the synthesis of Al3BC3 powder were optimized, and the synthetic mechanism was investigated. The mechanical mixing of the raw powders promoted the formation of secondary phases due to mechanical alloying effect and contamination. Nearly X-ray pure Al3BC3 powder was obtained after the calcination of the raw powder mixture at 1800°C for 2 h in Ar by suppressing the vaporization of aluminum. During calcination, Al4C3 layer was formed at the surface of aluminum powder by the reaction with carbon, which maintained the morphology of the aluminum powder above its melting temperature. The nucleation and growth of Al3BC3 within aluminum melt began to occur at 1000°C, and became the main synthetic mechanism of Al3BC3 at 1100°C. The Al3BC3 particles synthesized at 1100°C were porous and were composed of fine hexagonal crystals. The main synthetic mechanism of A3BC3 changed into solid–solid reaction above 1100°C, and a gas–solid reaction promoted the densification of the porous Al3BC3 powder above 1340°C. [ABSTRACT FROM AUTHOR]

Aluminum-containing ternary carbide, Al4SiC4, was successfully synthesized using a mixture of Al(OH)3, SiO2, and phenolic resin by a carbothermal reduction process without any posttreatment. In addition, the processing parameters were optimized in this study. Unlike the JCPDS pattern of Al4SiC4, the powder has a highly aligned structure along the c-axis, indicating a hexagonal plate-like morphology. The growth rate of particulates was higher than the nucleation rate as the carbon content decreased. The crystallinity (formation yield) of Al4SiC4 was much more dependent on the ratio of carbon to oxides than on the ratio of SiO2 to Al(OH)3. Possible reaction mechanisms responsible for the synthesis of ternary carbide are discussed by considering reactions at the initial and later stages during the carbothermal reduction process. [ABSTRACT FROM AUTHOR]

Aim: Henoch-Schönlein purpura (HSP) is a common childhood systemic vasculitis involving the skin, gastrointestinal tract, joint, kidneys and even scrotum. Methods: We retrospectively reviewed the clinical and laboratory data of 120 male patients with HSP and also evaluated the risk factors for scrotal involvement and the relation between scrotal involvement and other clinical features. Twenty-six out of 120 boys (21.7%) diagnosed with HSP had scrotal involvement. Results: Scrotal symptoms manifested as swelling in 88.5% and pain (or tenderness) in 69.2% of HSP patients with scrotal involvement. Neurologic symptoms, mainly headache and localized edema among various manifestations and high serum C3 level of laboratory profiles were more frequently observed in scrotal-involved group than in those of non-involved group. However, there was no difference in the outcomes of scrotal symptoms according to therapeutic modalities and the occurrence of scrotal involvement had no correlation with renal involvement from acute to chronic phase. Conclusions: We found that neurologic symptoms, localized edema and high serum C3 level show a significant relation with scrotal involvement in male HSP patients. Because scrotal involvement in male HSP patients is not rare, the accurate early diagnosis of HSP is mandatory by the early notification of purpura and imaging evaluations in order to avoid unnecessary procedures. [ABSTRACT FROM AUTHOR]