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51.
Accurate evaluation of metastatic lymph nodes (LNs) is indispensable for adequate treatment of colorectal cancer (CRC) patients. Here, we demonstrate detection of metastases of human CRC in removed fresh LNs using 5-aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) fluorescence. A spectral unmixing method was employed to reduce the overlap of collagen autofluorescence on PpIX fluorescence. A total of 17 surgery patients with advanced CRC were included in this study. After 5-ALA at a dose of 15 mg/kg of body weight was applied orally 2 h prior to surgery, 87 LNs were subjected to spectral fluorescence imaging and histopathological diagnosis, and statistical analysis was performed. No apparent side effect was observed to be associated with 5-ALA administration. The spectral unmixing fluorescence intensity of PpIX in metastatic LNs was 10.2-fold greater than that in nonmetastaic LNs. The receiver-operating-characteristic (ROC) analysis showed that the area under the curve (AUC) was calculated as 0.95. Our results show the potential of 5-ALA-induced PpIX fluorescence processed by spectral unmixing for detecting metastases in excised fresh LNs from patients with CRC, suggesting that this rapid and feasible method is applicable to gross evaluation of resected LN samples in pathology laboratories.  相似文献   
52.
Core-level and valence band spectra of InxGa1−xN films were measured using hard x-ray photoemission spectroscopy (HX-PES). Fine structure, caused by the coupling of the localized Ga 3d and In 4d with N 2s states, was experimentally observed in the films. Because of the large detection depth of HX-PES (∼20 nm), the spectra contain both surface and bulk information due to the surface band bending. The InxGa1−xN films (x = 0–0.21) exhibited upward surface band bending, and the valence band maximum was shifted to lower binding energy when the mole fraction of InN was increased. On the other hand, downward surface band bending was confirmed for an InN film with low carrier density despite its n-type conduction. Although the Fermi level (EF) near the surface of the InN film was detected inside the conduction band as reported previously, it can be concluded that EF in the bulk of the film must be located in the band gap below the conduction band minimum.  相似文献   
53.
Summary The hydrothermal processing has emerged as the new materials processing for powder preparation. This describes definition, history, advantages, characteristics of the powder, ideal and hydrothermal powder.  相似文献   
54.
Psychology is in a preparadigmatic or pre-unified stage of scientific development. Two characteristics of psychology's status are: (1) lack of cumulative scientific growth and (2) experimental-theoretical overgeneralization. The reinforcer, as a construct in theories and as a critical element of behavioral change, has been a casualty of the separatism between such factions as radical behaviorism and cognitive psychology. In the end, psychology as a progressive science has been impeded, and psychological practitioners have been left to use intervention techniques that are not the most effective or efficient. In order to improve upon this situation, unification is needed between radical behaviorism and cognitive psychology, among other disciplines. However, the issue of the reinforcer is only one of many areas where such unification should be pursued and attained. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
55.
Fast inverse offset computation using polygon rendering hardware   总被引:2,自引:0,他引:2  
Mold and die parts are usually fabricated using 3-axis numerically controlled milling machines with ball-end, flat-end or round-end cutters. The cutter location (CL) surface representing a trajectory surface of the cutter's reference point when the cutter is slid over a part is important for preventing the gouging problem. This surface is equivalent to the inverse offset shape of the part, which is the top surface of the swept volume of the inverse cutter moving around the part surface. The author proposes a fast computation method of the inverse offset shape of a polyhedral part using the hidden-surface elimination mechanism of the polygon rendering hardware. In this method, the CL surface is obtained by simply rendering the component objects of the swept volume. An experimental program is implemented and demonstrated.  相似文献   
56.
Zirconia–ceria solid solutions of tetragonal symmetry ( t 'ZrO2) containing 30 to 65 mol% ceria were prepared by annealing c '-ZrO2 at 627°C samples sintered at 1660–1760°C, where c '-ZrO2 is defined as a cubic or tetragonal phase whose axial ratio c/a (tetragonality) is equal to 1. The lattice parameters and the cube root of the unit cell volumes of the annealed samples increased linearly with the ceria content but, on the other hand, the axial ratio c/a (tetragonality) decreased to 1.000 at 70 mol%. During the annealing of each sample, the cell volume decreased because the residual Ce3+ ions were oxidized to the smaller Ce4+. The temperature–time–transformation (TTT) diagram of the 1:1 solid solution was investigated for the c'-t' diffusionless phase transition and the c'–(t + c) diffusional reaction. The c'–t' transformation was found to behave as a thermally activated process with an activation energy estimated to be 113 kJ/mol. This value may indicate that c'–t' transformation is controlled by oxygen diffusion accompanied by dimensional changes of the cerium ions.  相似文献   
57.
Radon is one of the noble gases, which are chemically inert and do not make any reactants under normal conditions. In this experiment we demonstrated an enigmatic reaction between radon and fluorine when a corona discharge is used as a promoter. Distinctive changes in radon concentrations were caused by the discharge and a trap efficiency of >99.5% was estimated. The mass balance between the trapped and the released radon was found to be reasonable. This indicates the existence of chemical reactions with radon. This trap phenomenon has application as a technique for reducing radon concentration in radon-contaminated air. It is possible that this technique will be applicable to other noble gases.  相似文献   
58.
Dislocation networks and small-angle grain boundaries were observed to form among damage shells produced around B particles in B-doped Cu specimens neutron irradiated to a thermal dose of 3.0 × 1019n/cm2 at about 70°C. The microstructures are formed as a results of the interaction of dislocations generated by strain induced around a damage shell with dislocations generated from the other damage shell. The small-angle grain boundaries are formed to relax the strain induced between closely spaced damage shells.  相似文献   
59.
The low-temperature oxidation of five coals, ranging in rank from subbituminous to anthracite, was studied in the temperature range 30–250 °C, and the reaction kinetics were elucidated. The reaction rates were independent of particle diameter <1 mm. The orders of reaction for CO2 and CO formation were 0.50 and 0.54, respectively, with respect to oxygen. Activation energies of 51.5–59.4 kJ mol?1 were obtained for the CO2 and CO formation reactions. The rates of formation of CO2 and CO were correlated to the internal surface area and the oxygen contents of the coals. It was found that pores having radii >100 Å, and the oxygen-containing groups which decompose to CO2 and/or CO, were playing important roles in low-temperature oxidation of coals.  相似文献   
60.
Low-temperature phase equilibria ranging from 1000° to 1200°C in the ZrO2–CeO2 system were investigated by annealing compositionally homogeneous ZrO2–CeO2 solid solutions in a Na2B2O7.1 NaF flux. The 5 mol% CeO2 samples decomposed into monoclinic ( m ) and tetragonal ( t ) phases during annealing at 1100°2 and 1120°C, and the t -phase transformed diffusionlessly into monoclinic ( m ') symmetry during quenching. A eutectoid reaction, t → ( m + c ), was confirmed to occur at 1055°± 10°C, where the equilibrium compositions of the t -, m -, and c -phases were 11.2 ± 2.8, 0.9 ± 0.9, and 84 ± 1 mol% CeO2, respectively. The equilibrium phase boundaries were almost independent of the annealing time and/or the flux:sample ratio, which indicates that the flux accelerates the reaction rate withouts affecting the equilibration. The previous data are discussed using metastable–stable phase diagrams. The discrepancies of the low-temperature phase diagram in the literature are attributable to either regarding the metastable phase boundaries as stable ones or ignoring the sluggish kinetics.  相似文献   
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