Analysis of deformation mechanisms in magnesium single crystals using a dedicated four-point bending tester

In this study,we explored the deformation mechanisms of Mg single crystals using a combination of scanning electron microscopy and electron backscattered diffraction in conjunction with a dedicated four-point bending tester.We prepared two single-crystal samples,oriented along the<1120>and<1010>directions,to assess the mechanisms of deformation when the initial basal slip was suppressed.In the<1120>sample,the primary{1012}twin(T1)was confirmed along the<1120>direction of the sample on the compression side with an increase in bending stress.In the<1010>sample,T1 and the secondary twin(T2)were confirmed to be along the<1120>direction,with an orientation of±60°with respect to the bending stress direction,and their direction matched with(0001)in T1 and T2.This result implies that crystallographically,the basal slip occurs readily.In addition,the<1010>sample showed the double twin in T1 on the compression side and the tertiary twin along the<1010>direction on the tension side.These results demonstrated that the maximum bending stress and displacement changed significantly under the bend loading because the deformation mechanisms were different for these single crystals.Therefore,the correlation between bending behavior and twin orientation was determined,which would be helpful for optimizing the bending properties of Mg-based materials.

Characterization of deformation transition in the rolled LZ91 magnesium alloy under tensile loading

In this study,the mechanical behavior of crystal group of hexagonal close-packed(hcp;αphase)and body-centered cubic(bcc;βphase)during tensile loading was investigated to elucidate the mechanism from elastic to plastic deformation transition of the rolled LZ91 Mg alloy using transmission-X-ray diffraction(transmission-XRD)measurement,transmission electron microscopy(TEM),scanning transmission electron microscopy(STEM),energy dispersive X-ray spectroscopy(EDS).The approximate proof stress of the LZ91 Mg alloy sample was found that the lattice strain retained the expanded state from 0.6%nominal strain,and the transmission-XRD measurement characterized the crystalline behavior during the transition by the integrated intensity of crystal group hcp(100).The lattice strain of bcc(110)decreased from the 0.6%nominal strain due to dislocation activity,which occurred nearβ/βgrain boundary.In addition,we performed the analyses of electron energy loss spectroscopy(EELS)modes,the Li-K peak disappeared from the segregated Li regions of 10–60 nm nearβ/βgrain boundary at the nominal strain of 0.8%.Understanding this mechanical behavior during the elastic to plastic deformation transition by transmission-XRD is crucial for the development of Mg-Li alloys.

Sporadic gastric carcinoid tumor successfully treated by two-stage laparoscopic surgery:A case report

We report a case of sporadic gastric carcinoid tumor successfully treated by two-stage laparoscopic surgery.A 38-year old asymptomatic woman was referred to our hospital for evaluation of a submucosal tumor of the stomach.Endoscopic examination showed a solitary submucosal tumor without ulceration or central depression on the posterior wall of the antrum and biopsy specimens were not sufficient to determine the diagnosis.Endoscopic ultrasound revealed a tumor nearly 2 cm in diameter arising from the muscle layer and a computed tomography scan showed the tumor enhanced in the arterial phase.Laparoscopic wedge resection was performed for definitive diagnosis.Pathologically,the tumor was shown to be gastric carcinoid infiltrating the muscle layer which indicated the probability of lymph node metastasis.Serum gastrin levels were normal.As a radical treatment,laparoscopy-assisted distal gastrectomy with regional lymphadenectomy was performed 3 wk after the initial surgery.Finally,pathological examination revealed no lymph node metastasis.

Expected clinical applications of circulating tumor cells in breast cancer

Tumor cell invasion and intravascular filtration lead to the presence of circulating tumor cells(CTCs)in peripheral blood.CTCs have,thus,been counted in patients with cancer to analyze metastatic mechanisms or in the hope of developing clinical applications for diagnosis and therapy;various CTC-related studies have been performed.However,the clinical significance of CTCs remains to be established because of the extremely small number of CTCs in peripheral blood as compared with the number of blood cells.Technical problems(e.g.reproducibility and reliability)in the detection of CTCs also remain to be solved.The use of flow cytometric analysis,which can be performed with tumor-cell markers such as anti-epithelial cell adhesion molecule antibodies and anti-cytokeratin antibodies and nontumor-cell markers such as anti-CD45 antibodies has enhanced specificity for the detection of tumor cells.The CellSearch System?can detect 1 CTC in 7.5 mL of peripheral blood,with high reproducibility.Its detection rate and accuracy for CTCs have been confirmed.In the United States,clinical trials have used this system to detect CTCs in patients with metastatic breast cancer,metastatic colorectal cancer,and metastatic prostate cancer,and CTCs have been confirmed to be a useful prognostic factor.This system was also suggested to be useful for monitoring treatment response in patients with metastatic breast cancer and was approved by the United States Food and Drug Administration in 2004.Measuring CTC counts can facilitate the early prediction of treatment response and thereby avoid unnecessary therapy.CTCs may also be a useful biomarker for molecular targeted agents,enabling the identification of patients most likely to respond to a given treatment and facilitating treatment selection.However,the widespread use of CTC monitoring as a routine examination requires a further improvement in measurement sensitivity,the establishment of criteria for quantitative and qualitative evaluations,and additional clear-cut evidence supporting the clinical significance of CTCs.We expect that CTCs will be established to be a new diagnostic and therapeutic index for breast cancer.

研制小型风冷吸收式组装空调机的进展

在日本,燃气直燃式空调系统多用于大型建筑,而在中、小型建筑中,空调设备主要由电动组装热泵占领着市场。从1993年10月起,我们一直在研制风冷燃气吸收式组装空调机。该装置是一台燃气双作用吸收式机组和一台风冷吸收器及冷凝器。翅片盘管不需要冷/热水回路,泵或室内机组。制冷的设计COP(成绩系数)是0.8或更高一些,制冷能力是17.6kw。各组成单元分别予以试验,然后组装于一台组合式样机,该机的制冷能力是13.0kw。预计1997年可实现该机的商业化。

Evaluation of temperature dependent vortex pinning properties in strongly pinned YBa_(2)Cu_(3)O_(7-δ)thin films with Y_(2)BaCuO_(5)nanoinclusions

The pinning of quantized magnetic vortices in superconducting YBa_(2)Cu_(3)O_(7-δ)(YBCO or Y123)thin films with Y_(2)BaCuO_(5)(Y211)nanoinclusions have been investigated over wide temperature range(4.2-77 K).The concentration of Y211 nanoinclusions has been systematically varied inside YBCO thin films prepared by laser ablation technique using surface modified target approach.Large pinning force density values(Fp∼0.5 TNm^(−3)at 4.2 K,9 T)have been observed for the YBCO film with moderate concentration of Y211 nanoinclusions(3.6 area%on ablation target).In addition,uniform enhancement in critical current density(J_(c))was observed in the angular dependent J_(c)measurement of YBCO+Y211 nanocomposite films.Y211 nanoinclusions have been found to be very efficient in pinning the quantized vortices thereby enhancing the in‐field J_(c)values over a wide range of temperature.Increasing the concentration of Y211 secondary phase into Y123 film matrix results into agglomeration of Y211 phase and observed as increased Y211 nanoparticle size.These larger secondary phase nanoparticles are not as efficient pinning centers at lower temperatures as they are at higher temperatures due to substantial reduction of the coherence length at lower temperatures.Investigation of the temperature dependence of J_(c)for YBCO+Y211 nanocomposite films has been conducted and possible vortex pinning mechanism in these nanocomposite films has been discussed.

Time course of expression of intermediate filament protein vimentin,nestin and desmin in rat renal glomerular injury

Podocytes in renal glomemlus express unusual intermediate filament proteins （IFs） for visceral epithelial cells. IFs cytoskeleton is mainly composed of vimentin, nestin and desmin. Tissue injury is often accompanied by changes in gene expression of IFs. Enhanced desmin staining in variety of rat experimental including 2 4 puromycin nephrosis. It has not podocytes are observed in a models of podocyte injury aminonucleoside （PAN） been elucidated whether expression of vimentin and nestin is up-regulated in podocyte injury. To further gain insight into expression of IFs in podocytes, we investigated the time course of vimentin, nestin and desmin in PAN nephrosis.