Peroxiredoxin 2 as a chemotherapy responsiveness biomarker candidate in osteosarcoma revealed by proteomics

Purpose : We aimed to identify novel chemotherapy responsiveness biomarkers for osteosarcoma (OS) by investigating the global protein expression profile of 12 biopsy samples from OS patients. Experimental design : Six patients were classified as good responders and six as poor responders, according to the Huvos grading system. The protein expression profiles obtained by 2‐D DIGE consisted of 2250 protein spots. Results : Among them, we identified 55 protein spots whose intensity was significantly different (Bonferroni adjusted p‐value<0.01) between the two patient groups. Mass spectrometric protein identification demonstrated that the 55 spots corresponded to 38 distinct gene products including peroxiredoxin 2 (PRDX 2). Use of a specific antibody against PRDX 2 confirmed the differential expression of PRDX 2 between good and poor responders, while PRDX 2 levels as measured by Western blotting correlated highly with their corresponding 2‐D DIGE values. The predictive value of PRDX 2 expression was further confirmed by examining an additional four OS cases using Western blotting. Conclusions and clinical relevance : These results establish PRDX 2 as a candidate for chemotherapy responsiveness marker in OS. Measuring PRDX 2 in biopsy samples before treatment may contribute to more effective management of OS.     

Ultra light-weight and high-resolution X-ray mirrors using DRIE and X-ray LIGA techniques for space X-ray telescopes

We are developing novel ultra light-weight and high-resolution X-ray micro pore optics for space X-ray telescopes. In our method, curvilinear micro pore structures are firstly fabricated by silicon deep reactive ion etching (DRIE) or X-ray LIGA processes. Secondly, side walls of the micro structures are smoothed by magnetic field assisted finishing and/or hydrogen annealing techniques for high reflectivity mirrors. Thirdly, to focus parallel X-ray lights from astronomical objects, these structures are elastically or plastically bent into a spherical shape. Fourthly, the bent structures are stacked to form a multi-stage X-ray telescope. In this paper, we report on fabrication and X-ray reflection tests of silicon and nickel X-ray mirrors using the DRIE and LIGA processes, respectively. For the first time, X-ray reflections were confirmed on both of the mirrors. Estimated rms roughnesses were 5 nm and 3 nm for the silicon and nickel mirrors, respectively.     

Vertical liquid transportation through capillary bundle structure using centrifugal force

The use of three-dimensional (3D) microstructures is becoming essential attempt to develop next generations’ microdevices, to integrate many modules and various functions, and enhance the performance of device. In this paper, we present a new concept for lab on a chip using 3D structure and centrifugal pumping for integrated functional fluid systems such as high-throughput screening, and point of care testing systems which has stacked multiple structures with 3D-interconnection. The use of 3D structure brings many benefits for above high throughput systems, such as possibility to integrate various modules enabling to perform total assay operation, from sample preparation for biochemical reaction and their detection on one platform. For this concept, the most important key technology is control of a vertical valving and transportation of liquid between different 2D micro channel networks with different height levels. We demonstrated such vertical liquid transportation in 3D micro channel networks through the high aspect ratio capillary bundle filter by controlling spinning speed of device and centrifugal force as a pumping force, and confirmed capillary bundle could be employed as vertical microvalve for 3D fluidic systems using centrifugal force as a pumping method.     

PROPAGATION AND CLOSURE OF SHORT FATIGUE CRACKS AT NOTCHES UNDER COMPRESSIVE MEAN STRESSES

Abstract— Single-edge-notched specimens of a low-carbon steel were fatigued under cyclic in-plane bending with compressive mean stresses. The development of crack closure with crack growth was studied both experimentally and theoretically. The relation between the crack opening stress and the crack length was a function of the minimum (compressive) applied stress, irrespective of the maximum stress. The effective stress intensity range was a unique parameter in correlating the crack growth rate, even if the crack was embedded in the compressive plastic zone. Under a constant minimum stress, the length of nonpropagating cracks became longer with increasing maximum applied stress. A theoretical model was proposed for predicting the crack opening stress on the basis of the compressive stress distribution at the minimum applied stress. The predicted value agreed fairly well with the experimental result. The model gave upper bounds of the crack growth rate and the length of nonpropagating fatigue cracks within the plastic zone.     

Capturing of transition by the RNG based algebraic turbulence model

This paper concerns the RNG based algebraic turbulence model. This model has characteristics to capture transitional process from laminar to turbulent flow. This is determined by the argument of the Heaviside function, which becomes a threshold for the occurrence of turbulence. It is supposed that proper modeling of this argument will lead to correctly capture transition location. In the present paper, this argument is modeled in such a way that the form of cubic equation for the turbulent kinematic viscosity be maintained. Moreover, the length scale which is required to calculate the turbulent kinematic viscosity is newly proposed, taking into account the freestream pressure gradient. The validation is performed by comparing the calculated results with the empirical expressions as well as the experimental data. This model can simulate the streamwise intermittency effect, by which a sudden increase of skin friction is prevented. Moreover, the transition location can be predicted within reasonable accuracy compared with the experimental data.     

Numerical computation of thermally controlled steam bubble condensation using Moving Particle Semi-implicit (MPS) method

In the present study, single steam bubble condensation behaviors in subcooled water have been simulated using Moving Particle Semi-implicit (MPS) method. The liquid phase was modeled using moving particles and the two phase interface was set to be a movable boundary which can be tracked by the topological position of the interfacial particles. The interfacial heat transfer was determined according to the heat conduction through the interfacial liquid layer and the coupling between momentum and energy was specially treated. Computational results showed that the bubble experiences various deformations at lower degrees of liquid subcooling while it remains nearly spherical at higher degrees of liquid subcooling. The bubble lifetime is nearly proportional to bubble size and is prolonged at higher system pressures. Bubble lifetime obtained from the MPS method agrees well with the experiments of 10 and 11, however it is lower than the predictions of Sudhoff et al. (1982). The underestimation is caused by severe bubble deformation at lower degrees of subcooling. The present study exhibits some fundamental characteristics of single steam bubble condensation and is expected to be instructive for further applications of the MPS method to evaluate more complicated bubble dynamics problems.     

Plastic Buckling Transition Modes in Moderately Thick Cylindrical Shells

Moderately thick perfect cylindrical shells under axial compression first exhibit an axisymmetric buckling mode, where a localization of buckling patterns, referred to as an elephant foot bulge, is caused by the first plastic bifurcation. However, the transition from the axisymmetric buckling mode to a nonaxisymmetric buckling mode, referred to as a diamond buckling mode, may occur due to the next bifurcation if we continue the loading under displacement control. Herein, this phenomenon is examined, based on a rigorous plastic bifurcation analysis. As a result, it is observed that the circumferential wave number of the diamond buckling mode increases with the decrease of the wall thickness. The boundary conditions also considerably influence the occurrence of diamond buckling. It is found that the strain concentration is intensified for the diamond buckling modes, compared with the axisymmetric modes.     

Determination of Mark-Houwink-Sakurada equation for phenolic resins containing alkylenediamine in the main chain and estimation of their molecular conformation in tetrahydrofuran solution

Summary Phenolic resins containing alkylenediamine in the main chain could be prepared by the co-condensation reaction of phenol, formaldehyde and alkylenediamines such as ethylenediamine and hexamethylenediamine. The molecular structures were determined by¹H-NMR spectra, IR spectra and nitrogen content. The molecular conformation of these resins in THF solution were studied from the viscosity measurements, and it became clear that the molecules were considerably compact compared with linear vinyl polymers. To clarify the reason of this phenomenon, the resins whose degrees of branching were different from each other and the resins whose phenolic hydroxyl groups were acetylated were prepared. From viscosity data, it was pointed out that the intramolecular hydrogen bonding contributes to the compaction of the phenolic resins containing alkylenediamine in the main chain more strongly than the branching does.