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1.
View-based approach for learning and recognition of 3D object and its pose detection was proved to be affective and efficient, except its high learning cost. In this research, we propose a virtual learning approach which generates learning samples of views of an object from its 3D view model obtained by motion-stereo method. From the generated learning sample views, features of high-order autocorrelation are extracted, and discriminant feature spaces for object recognition and pose detection are built. Recognition experiments on real objects are carried out to show the effectiveness of the proposed method. Caihua Wang, Ph.D.: He received his B.S. in mathematics and M.E. in electronic engineering from Renmin University of China, Beijing, China in 1983 and 1986, and his Ph. D. from Shizuoka University, Hamamatsu, Japan in 1996. He is a JST domestic fellow and is doing his post doctoral research at Electrotechnical Laboratory. His research interests are computer vision and image processing. He is a member of IEICE and IPSJ. Katsuhiko Sakaue, Ph.D.: He received the B.E., M.E., and Ph.D. degrees all in electronic engineering from University of Tokyo, in 1976, 1978 and 1981, respectively. In 1981, he joined the Electrotechnical Laboratory, Ministry of International Trade and Industry, and engaged in researches in image processing and computer vision. He received the Encouragement Prize in 1979 from IEICE, and the Paper Award in 1985 from Information.  相似文献   
2.
In-situ analysis for SiC bulk single crystal growth was reported using vertical X-ray diffractometer system. A furnace for SiC sublimation growth combined with the XRD system which possessed three kinds of functions including topography, rocking curve measurement and crystal growth rate monitoring was developed. These functions could contribute as a powerful tool finding the optimum growth condition by dynamic observation in the crucible. In this study, the in-situ X-ray topographs succeeded to capture dynamic elongation of defects and dislocation generated in the SiC growing crystals. The in-situ rocking curve measurement reviled appearance of mosaic structure in the SiC crystal grown with high growth rate. The in-situ growth rate monitoring also succeeded very precisely using the direct X-ray beam absorption. On the base of findings and facts obtained by the in-situ observations, the importance for the SiC growth was discussed.  相似文献   
3.
Malignant pleural effusion (MPE) provides a liquid tumor microenvironment model that includes cancer cells and immune cells. However, the characteristics of tumor antigen-specific CD8+ T cells have not been investigated in detail. Here, we analyzed MPE samples taken from a patient with pancreatic cancer who received a dendritic cell vaccine targeting Wilms’ Tumor 1 (WT1) antigen over the disease course (two points at MPE1st and 2nd, two months after MPE1st). Epithelial cell adhesion molecule (EpCAM)+ cancer cells (PD-L1 or T cell immunoglobulin mucin-3, TIM-3), both PD-1 or TIM-3 positive CD8+ T cells, and CD14+CD68+CD163+TIM-3+ macrophages increased from the MPE1st to MPE2nd. The ratio of WT1-specific cytotoxic lymphocytes (WT1-CTLs) to MPE CD8+ T cells and IFN-γ secretion of WT1-CTLs were reduced with disease progression. Coincidentally, the fraction of central memory T (TCM) of WT1-CTLs was decreased. On the other hand, CD8+ T cells in response to SMAD4P130L, which is homogeneously expressed in EpCAM+ cancer cells, were detected using in vitro expansion with the HLA-A*11:01 restrictive SVCVNLYH neoantigen. Furthermore, the CD8+ T cell response to SMAD4P130L was diminished following remarkably decreased numbers of CD8+ TCM in MPE samples. In conclusion, CD8+ T cells responding to WT1 or SMAD4P130L neoantigen expressed in EpCAM+ pancreatic cancer cells were detected in MPE. A tumor antigen-specific immune response would provide novel insight into the MPE microenvironment.  相似文献   
4.
The pathophysiology of early-stage hip osteoarthritis (EOA) is not fully understood. Although a previous study in an age-unmatched cohort reported that the number of macrophages was increased in knee EOA compared to late OA (LOA), it remained unclear whether increased macrophages in EOA accurately reflect EOA pathology. We investigated the differences in CD14 expression levels between EOA and LOA using age-unmatched and -matched cohorts. Synovial tissues were obtained from 34 EOA (Tönnis grades 0 and 1) and 80 LOA (Tönnis grades 2 and 3) patients. To correct for differences in demographics between patients with LOA and EOA, we also created propensity score-matched cohorts (16 EOA and 16 LOA). CD14 expression and its association with pain was estimated in LOA and EOA before and after propensity matching. We performed flow cytometry on tissues from the 16 patients, with 8 from each group, to assess for CD14+ subsets in the cells. The CD14 expression in EOA was higher than that in LOA both before and after propensity matching. The proportion of CD14high subsets in EOA was higher than that in LOA. The CD14 expression was associated with pain in EOA before matching. However, no difference was observed between the pain and CD14 expression after matching in EOA. The increased CD14 expression and the proportion of CD14high subsets may be important features associated with hip EOA pathology. To accurately compare early and late OA, the analysis of a propensity score-matched cohort is necessary.  相似文献   
5.
Flashing light from blue light emitting diodes is an effective method for the reduction of energy consumption in the bioproduction of astaxanthin by Haematococcus pluvialis. We investigated the effects of light intensity and frequency on the final astaxanthin concentration in bioproduction by H. pluvialis grown mixotrophically. The final astaxanthin concentration under illumination with flashing light, with frequencies ranging from 25 to 200 Hz, was dependent on the light intensity and on the duty cycle and was equivalent, or higher, in comparison with that under illumination with continuous light at the same incident intensity. The light intensity determined the maximum attainable concentration of astaxanthin under continuous illumination. Under illumination with flashing light, the ratio of the final astaxanthin concentration to the maximum concentration at a specific light intensity was correlated to the duty cycle in the frequency range from 25 to 200 Hz. The effect of lower frequencies on enhanced astaxanthin production under flashing light was also studied; at levels as low as 1 Hz, higher final astaxanthin concentrations were observed under flashing light compared to concentrations attained under continuous light.  相似文献   
6.
Crude rice bran protein (CRBP) was prepared by alkaline extraction and then treated with 0.6 m HCl to remove phytic acid. The phytate‐free rice bran protein (PFRBP) was hydrolysed with proteases M, N, S, P and pepsin under optimal conditions. Hydrolysates obtained from various hydrolysis periods were subjected to analysis for their degree of hydrolysis (DH) and functional properties. The hydrolysates were fractionated by reversed‐phase column chromatography on Kaseigel ODS resin (120–140 μm) using a stepwise gradient of aqueous ethanol, and their activities were measured. The 40% ethanol fraction of protease P 4 h‐hydrolysate was separated by successive reversed‐phase high‐performance liquid chromatography and the amino acid sequences of isolated antioxidative peptides were determined by a protein sequencer and matrix‐assisted laser desorption ionisation‐time of flight mass spectrometry. Crude rice bran protein had higher antioxidative activity than PFRBP, due to the presence of phytic acid. Phytate contents of rice bran, CRBP and PFRBP were 2.5%, 1.42% and 0%, respectively. The activity of PFRBP increased upon protease digestion. Protease M hydrolysates showed the highest DH, but the lowest antioxidative activity. Hydrolysates with DH below 10% had higher antioxidative activity than those above 20%. This result indicates that the antioxidative activity of the hydrolysates is inherent to their characteristics amino acid sequences of peptides depending on the protease specificities.  相似文献   
7.
The rates of degradation of cyanuric acid, a key intermediate in a metabolic pathway of s-triazine herbicides, were measured for Pseudomonas sp. NRRL B-12227. The rate of degradation was affected by the rate of cyanuric acid transport through cell membranes and the activity of cyanuric acid amidohydrolase inside the cells. At low concentrations of cyanuric acid, the acclimation of cells to cyanuric acid and/or added nutrients effectively enhanced the degradation rate. The strain was also applied to bioremediation using a Bioremediation with Self-Immobilization System (BSIS), in which Pseudomonas sp. NRRL B-12227 cells were co-immobilized with Bacillus subtilis, the latter of which secretes a viscous polymer, in a shallow layer of soil packed in a column. More than 70% of the Pseudomonas sp. NRRL B-12227 cells were co-immobilized with the B. subtilis in a 7.5 cm layer of the packed soil by self-aggregation. More than 60% of the 1 mM cyanuric acid supplied to the packed soil was degraded in this layer during a 72 h period.  相似文献   
8.
Trehangelins are trehalose angelates discovered from endophytic actinomycete Polymorphospora rubra K07‐0510. We identified the trehangelin biosynthetic gene cluster, including genes that encode a glycoside hydrolase‐like protein (thgC), α‐amylase (thgD), 3‐ketoacyl‐ACP synthase III (thgI), 3‐ketoacyl‐ACP reductase (thgK), enoyl‐CoA hydratase (thgH) and acyl transferase (thgJ). Heterologous expression of thgH, thgI, thgJ and thgK confirmed the importance of these genes in the biosynthesis of trehangelin A. Enzymatic activity studies showed that ThgI catalyses the condensation of acetyl‐CoA and methylmalonyl‐CoA to 2‐methylacetoacetyl‐CoA (MAA‐CoA), ThgK catalyses NADPH‐dependent reduction of MAA‐CoA to 3‐hydroxy‐2‐methylbutyryl‐CoA (HMB‐CoA) and ThgH catalyses the dehydration of HMB‐CoA to angelyl‐CoA (AN‐CoA). This is the first report on the elucidation of the enzymatic formation of AN‐CoA.  相似文献   
9.
The dehydrogenation of methylcyclohexane (MCH) to toluene (TOL) for hydrogen production was theoretically and experimentally investigated in a bimodal catalytic membrane reactor (CMR), that combined Pt/Al2O3 catalysts with a hydrogen‐selective organosilica membrane prepared via sol‐gel processing using bis(triethoxysilyl) ethane (BTESE). Effects of operating conditions on the membrane reactor performance were systematically investigated, and the experimental results were in good agreement with those calculated by a simulation model with a fitted catalyst loading. With H2 extraction from the reaction stream to the permeate stream, MCH conversion at 250°C was significantly increased beyond the equilibrium conversion of 0.44–0.86. Because of the high H2 selectivity and permeance of BTESE‐derived membranes, a H2 flow with purity higher than 99.8% was obtained in the permeate stream, and the H2 recovery ratio reached 0.99 in a pressurized reactor. A system that combined the CMR with a fixed‐bed prereactor was proposed for MCH dehydrogenation. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1628–1638, 2015  相似文献   
10.
Tetraphenylethylene (TPE) derivatives have strong fluorescence in aggregated state. We report here an oligosaccharide binding assay system using tetraphenylethylene derivatives bearing oligosaccharides with aggregation-induced emission (AIE) characteristics. A tetraphenylethylene derivative bearing 6'-sialyllactose (6'SL) bound to microbeads coated with SSA lectin more effectively than RCA120 lectin. Microbeads that bound to fluorescent oligosaccharide probes could be detected by flow cytometric analysis. Tetraphenylethylene derivatives bearing oligosaccharides are useful for flow cytometric analysis of lectin-oligosaccharide interactions.  相似文献   
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