Analysis of the Circulating Tumor Cell Capture Ability of a Slit Filter-Based Method in Comparison to a Selection-Free Method in Multiple Cancer Types

Circulating tumor cells (CTCs) are a promising biomarker for cancer liquid biopsy. To evaluate the CTC capture bias and detection capability of the slit filter-based CTC isolation platform (CTC-FIND), we prospectively compared it head to head to a selection-free platform (AccuCyte^®-CyteFinder^® system). We used the two methods to determine the CTC counts, CTC positive rates, CTC size distributions, and CTC phenotypes in 36 patients with metastatic cancer. Between the two methods, the median CTC counts were not significantly different and the total counts were correlated (r = 0.63, p < 0.0001). The CTC positive rate by CTC-FIND was significantly higher than that by AccuCyte^®-CyteFinder^® system (91.7% vs. 66.7%, p < 0.05). The median diameter of CTCs collected by CTC-FIND was significantly larger (13.0 μm, range 5.2–52.0 vs. 10.4 μm, range 5.2–44.2, p < 0.0001). The distributions of CTC phenotypes (CK+EpCAM+, CK+EpCAM− or CK−EpCAM+) detected by both methods were similar. These results suggested that CTC-FIND can detect more CTC-positive cases but with a bias toward large size of CTCs.     

Development of a new apparatus to observe microcirculation chronically in continuous flow blood pump research

To observe microcirculation chronically is an important key to the successful evaluation of the continuous flow blood pump. In this study, we succeeded in developing a new apparatus by which microcirculation could be observed chronically without a microscope in a conscious animal. The apparatus utilizes a charge coupled device (CCD). A thin living tissue, such as mesentery, is put directly on a highly integrated CCD and is lit up through the tissue with a light-emitting diode (LED). The vascular nets in the tissue are projected onto the CCD like a contact photograph, which is then sent to a television screen and which can be used to analyze their motion and function. A 0.5-inch CCD having 250,000 pixels was used in this study. The cover glass of the CCD was removed, and a fiber optic plate was fixed onto the surface of the CCD for the tissue to be able to contact with the apparatus surface without clearance. The CCD as well as the LED were molded with epoxy resin for electrical insulation. The apparatus was 35 mm wide and 12 mm high with a micro stand for an LED, which can be easily implanted into an animal. The apparatus was implanted into a rabbit for 12 h. The configuration of arterioles and venules, tens of micrometers in diameter, and their motions in subcutaneous tissue could be observed.     

Emission rate of carbon dioxide while sleeping

Humans emit carbon dioxide (CO₂) as a product of their metabolism. Its concentration in buildings is used as a marker of ventilation rate (VR) and degree of mixing of supply air, and indoor air quality (IAQ). The CO₂ emission rate (CER) may be used to estimate the ventilation rate. Many studies have measured CERs from subjects who were awake but little data are available from sleeping subjects and the present publication was intended to reduce this gap in knowledge. Seven females (29 ± 5 years old; BMI: 22.2 ± 0.8 kg/m²) and four males (27 ± 1 years old; BMI: 20.5 ± 1.5 kg/m²) slept for four consecutive nights in a specially constructed capsule at two temperatures (24 and 28°C) and two VRs that maintained CO₂ levels at ca. 800 ppm and 1700 ppm simulating sleeping conditions reported in the literature. The order of exposure was balanced, and the first night was for adaptation. Their physiological responses, including heart rate, pNN_50, core body temperature, and skin temperature, were measured as well as sleep quality, and subjective responses were collected each evening and morning. Measured steady-state CO₂ concentrations during sleep were used to estimate CERs with a mass-balance equation. The average CER was 11.0 ± 1.4 L/h per person and was 8% higher for males than for females (P < 0.05). Increasing the temperature or decreasing IAQ by decreasing VR had no effects on measured CERs and caused no observable differences in physiological responses. We also calculated CERs for sleeping subjects using the published data on sleep energy expenditure (SEE) and Respiratory Quotient (RQ), and our measured CERs confirmed both these calculations and the CERs predicted using the equations provided by ASHRAE Standard 62.1, ASHRAE Handbook, and ASTM D6245-18. The present results provide a valuable and helpful reference for the design and control of bedroom ventilation but require confirmation and extension to other age groups and populations.     

Deformation near parallel cracks close to interface in bonded dissimilar plate

Tensile tests are carried out by using rectangular plate specimens extracted from the explosion clad plate. Artificial parallel cracks are made perpendicularly to the explosive interface in each specimen. When a tensile load is applied perpendicularly to the crack plane, strain, plastic deformation near cracks and crack opening displacement are examined by experiments as well as elasto-plastic finite element analysis. The effects of the material inhomogeneity, the change of material characteristics, the residual stress and the interaction between parallel cracks on the deformation behavior are revealed. The plastic zone around parallel cracks, at relatively low applied stress level, grows mainly ahead of and between two cracks. The interaction between parallel cracks on the crack opening displacement can be explained from the square of stress intensity factor at the low applied stress level and from the plastic deformation at the high applied stress level.     

Enlargement of viewing area of stereoscopic full-color LED display by use of a parallax barrier

In a stereoscopic full-color LED display by use of a parallax barrier, we discuss optimization of the viewing area, which depends on the width of the black regions between LEDs. Although conventional stereoscopic displays use a parallax barrier to permit the viewer to view stereoscopic images without any special glasses, their viewing area is restricted by crosstalk and the disappearing of pixels. Widening of the viewing area is examined by use of full-color panels with black regions having different widths. The optimum aperture ratio of the parallax barrier is obtained by analyzing the viewing area. An enlarged viewing area has been demonstrated by use of a 3-in-1 chip LED panel that has wider black regions than ordinary LED lamp cluster panels.     

Semi-solid processing of ultrahigh-carbon steel castings

Semi-solid processing using cooling plate technique was developed to produce a high quality ultrahigh-carbon steel (UHCS) components. Microstructure and mechanical properties were investigated as a function of fraction of solid. The microstructure of UHCS was improved using semi-solid processing. A unique homogenized microstructure comprised of fine particles grain size (200–100 μm) was obtained which totally differs from that obtained by ordinary UHCS casting (520 μm particle grain size). Tensile strength of as-cast and heat treated semi-solid processed UHCS is relatively high compared with ordinary one. Both the tensile strength and elongation closely connect with the particle grain size and cementite network changed with fraction of solid. Increasing fraction of solid increases hardness values, which is attributed to the fine and homogenous structure by semi-solid processing.     

Fabrication and mechanical characterization of continuous carbon fiber-reinforced thermoplastic using a preform by three-dimensional printing and via hot-press molding

A new 3D printer equipped novel nozzle structure for continuous carbon fiber-reinforced thermoplastics (C-CFRTP) was developed and the suitable printing conditions were studied. C-CFRTP filament and additional matrix resin were supplied independently using each extruder, which is useful for variety printing and precise form control in 3D printing. To measure the mechanical properties, specimens for tensile strength testing were fabricated using C-CFRTP filament (Vf:50%) without additional matrix resin. The experimental results indicate that the tensile strength and Young’s modulus were approximately 700 MPa and 53 GPa, respectively. The recrystallization effect through annealing after 3D printing yielded no drastic improvement. The mechanical properties were considerably improved by a hot-press treatment after 3D printing. The tensile strength and Young’s modulus increased to approximately 1400 MPa and approximately 90 GPa, respectively. These results suggest that one of the useful applications of C-CFRTP 3D printing technology is preforming of small parts in industrial products.     

A 10-b 50 MS/s 500-mW A/D converter using a differential-voltagesubconverter

A BiCMOS A/D converter using a “differential voltage subconverter,” which directly converts a voltage difference of complementary analog inputs to a digital code, is described. Fully differential architecture has advantages in immunity of common-mode error and in reduction of supply voltage. This differential-voltage subconverter realizes the fully differential A/D conversion without using interpolation technique. This subconverter is free from CR delay caused in the ladder resistors. Circuit techniques for high-accuracy conversion with single 5-V power supply, such as compensation technique for VBE modulation in emitter degeneration amplifier, are also described. A 10-b A/D converter is fabricated in a 0.8-μm BiCMOS process with f_T of 9 GHz. It successfully operates at 50 MS/s with 500-mW power consumption and with 5-V single supply