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Flows of a Rarefied Gas between Coaxial Circular Cylinders with Nonuniform Surface Properties  [PDF]
Toshiyuki Doi
Open Journal of Fluid Dynamics (OJFD) , 2019, DOI: 10.4236/ojfd.2019.91002
Abstract: Flows of a rarefied gas between coaxial circular cylinders with nonuniform surface properties are studied on the basis of kinetic theory. It is assumed that the outer cylinder is a diffuse reflection boundary and the inner cylinder is a Maxwell-type boundary whose accommodation coefficient varies in the circumferential direction. Three fundamental flows are studied: 1) a flow caused by the rotation of the outer cylinder (Couette flow), 2) a flow induced between the cylinders at rest kept at different temperatures (heat transfer problem), and 3) a flow induced by the circumferential temperature distribution along the cylindrical surfaces (thermal creep flow). The linearized ES-BGK model of the Boltzmann equation is numerically analyzed using a finite difference method. The time-independent behavior of the gas is studied over a wide range of the gas rarefaction degree, the radii ratio, and a parameter characterizing the distribution of the accommodation coefficient. Due to an effect of nonuniform surface properties, a local heat transfer occurs between the gas and the cylindrical surfaces in Couette flow; a local tangential stress arises in the heat transfer problem. However, the total heat transfer between the two cylinders in Couette flow and the total torque acting on the inner cylinder in the heat transfer problem vanish irrespective of the flow parameters. Two nondegenerate reciprocity relations arise due to the effect of nonuniform surface properties. The reciprocity relations among the above-mentioned three flows are numerically confirmed over a wide range of the flow parameters. The force on the inner cylinder, which also arises due to the effect of nonuniform surface properties in Couette flow and the heat transfer problems, is studied.
Application of the antibiotic disk diffusion method to multivariate profiling of soil bacterial community: comparing the power to discriminate different soils and dimension of the discrimination with that of the Biolog method
Doi, Ryoichi;
Brazilian Journal of Microbiology , 2003, DOI: 10.1590/S1517-83822003000400005
Abstract: the antibiotic disk diffution (add) method was compared with the biolog method in terms of power to discriminate soils and dimension of the discrimination. soils from a forest and a citrus field in thailand were profiled with these methods. these methods differentiated the soils in the principal component score plots. then, wilk's lambda statistic was determined to estimate power of these methods to discriminate the soils. the add method scored wilk's lambda of 0.003 (p = 0.144) and 0.000 (p=0.020), for direct and ratio-transformed calculation, respectively. the biolog method recorded wilk's lambda of 0.001 (p=0.067), 0.003 (p=0.144) and 0.035 (p=0.440), at 0.25, 0.50 and 0.75 average well color developments (awcds), respectively. the add method showed high discrimination power, or at least comparable to that of the biolog method. redundancy analysis (rda) resulted in ordination diagrams, which revealed a difference in dimension of the soil discrimination among the methods and the awcds. the soil environmental factors significantly related to the bacterial profiles at p=0.05 were: available phosphorus (add method and biolog 0.25 awcd), and ph (biolog 0.50 and 0.75 awcd). these results indicated that the profiling methods and the awcds revealed the multidimensionality of the discrimination. the possibility of the application of the add method to extraction of such pieces of information for effective land management was suggested.
Quantification of leaf greenness and leaf spectral profile in plant diagnosis using an optical scanner
Doi, Ryoichi;
Ciência e Agrotecnologia , 2012, DOI: 10.1590/S1413-70542012000300006
Abstract: observation of leaf spectral profile (color) enables suitable management measures to be taken for crop production. an optical scanner was used: 1) to obtain an equation to determine the greenness of plant leaves and 2) to examine the power to discriminate among plants grown under different nutritional conditions. sweet basil seedlings grown on vermiculite were supplemented with one-fifth-strength hoagland solutions containing 0, 0.2, 1, 5, 20, and 50 mm nh4+. the 5 mm treatment resulted in the greatest leaf and shoot weights, indicating a quadratic growth response pattern to the nh4+ gradient. an equation involving b*, black and green to describe the greenness of leaves was provided by the spectral profiling of a color scale for rice leaves as the standard. the color scale values for the basil leaves subjected to 0.2 and 1 mm nh4+ treatments were 1.00 and 1.12, respectively. the other treatments resulted in significantly greater values of 2.25 to 2.42, again indicating a quadratic response pattern. based on the spectral data set consisting of variables of red-green-blue and other color models and color scale values, in discriminant analysis, 81% of the plants were correctly classified into the six nh4+ treatment groups. combining the spectral data set with the growth data set consisting of leaf and shoot weights, 92% of the plant samples were correctly classified whereas, using the growth data set, only 53% of plants were correctly classified. therefore, the optical scanning of leaves and the use of spectral profiles helped plant diagnosis when biomass measurements were not effective.
Theoretical Status of Pentaquarks
Doi, Takumi
High Energy Physics - Phenomenology , 2007, DOI: 10.1143/PTPS.168.45
Abstract: We review the current status of the theoretical pentaquark search from the direct QCD calculation. The works from the QCD sum rule and the lattice QCD in the literature are carefully examined. The importance of the framework which can distinguish the exotic pentaquark state (if any) from the NK scattering state is emphasized.
Obscured Narrow-Line Seyfert 1 Galaxy Candidate Mrk 1388 with Nonthermal Jets
Akihiro Doi
Physics , 2014, DOI: 10.1093/pasj/psu147
Abstract: Mrk 1388 has an unusual Seyfert nucleus that shows narrow emission-line components without broad ones, but shows a strong featureless continuum and strong iron-forbidden high-ionization emission lines. The apparent coexistence of type-1/2 characteristics is potentially attributed to a heavily obscured broad-line region or to an intermediate-mass black hole with a broad-line component intrinsically narrower than those of typical narrow-line Seyfert 1 (NLS1) galaxies. Our observation using very-long-baseline interferometry (VLBI) reveals high-brightness radio emission from nonthermal jets from an active galactic nucleus (AGN) with a significant radio luminosity. Furthermore, we investigate the radial profile of the host galaxy using a Hubble Space Telescope (HST) image, which shows a Sersic index suggestive of a pseudobulge. Using the VLBI and HST results, which are essentially not affected by dust extinction, three individual methods provide similar estimates for the black hole mass: (0.76--5.4)x10^6 M_sun, 1.5x10^6 M_sun, and 4.1x10^6 M_sun. These masses are in a range that is preferential for typical NLS1 galaxies rather than for intermediate-mass black holes. Based on the estimated masses, the full width at half maximum $FWHM(H_\beta)$ of approximately 1200--1700 km/s should have been seen. The scenario of a heavily absorbed NLS1 nucleus can explain the peculiarities previously observed.
Evaluation of TlOH Effect for Pd0-Mediated Cross-Coupling of Methyl Iodide and Excess Boronic Acid Ester toward Fabrication of [11C]CH3-Incorporated PET Tracer  [PDF]
Hiroko Koyama, Hisashi Doi, Masaaki Suzuki
International Journal of Organic Chemistry (IJOC) , 2013, DOI: 10.4236/ijoc.2013.33030
Abstract: The use of thallium(I) hydroxide (TlOH) as a base is known to extremely accelerate the Suzuki-Miyaura cross-coupling reaction using organoboronic acid or organoboronic acid ester as a substrate. Here, we investigated the effects of TlOH by comparing with other conventional bases such as KOH, K2CO3, and CsF for Pd0-mediated rapid cross-coupling reactions between CH3I and organoborane reagents, such as phenyl-, (Z)-4-benzyloxy-2-butenyl-, and benzylboronic acid pinacol esters under the conditions CH3I/borane/Pd0/base (1:40:1:3) in THF/H2O or DMF/H2O for 5 min with an aim to fabricate a PET tracer efficiently. Consequently, however, the use of TlOH was much less efficient than the other bases for the acceleration of cross-coupling reactions. Thus, it was reconfirmed that the milder and non-toxic conditions using K2CO3 or CsF so far developed by our group were most appropriate for the rapid C-methylations.
Angle Effect to Dropping of Dew in Closed Suction Catheters  [PDF]
Kazuto Doi, Mayumi Doi, Yukoh Yaegashi, Katsuhisa Imoto, Masaru Ando, Junichi Kadota
Health (Health) , 2018, DOI: 10.4236/health.2018.106055
Abstract: Intratracheal aspiration in a patient on ventilation is generally performed using a catheter. Of late, closed suction systems have been used more frequently than open systems. To remove tracheal secretions through the intratracheal tube, catheter suction is used, and the suction catheter may be of the closed- or open-type. The catheters are cleaned by flushing with sterile 0.9% saline, resulting in dropping of dew. This phenomenon is caused by some factors: influence of flow, clogging of the suction tube, problem of manipulation of flushing and angle between the intubation tube and the connection port. But this dropping has not yet been investigated. In this study, we focused at this angle and we used the test lung which is simulated machine on behalf of patient. We consider two situations adult and child, also two types of catheters Eco-Cath and Ty-care. In child case we consider elbow-type suction catheters and Y-connector type. The angle was set at 0°, 20°, 40°, 60°, and 90°, and we observed the difference between Eco-Cath and Ty-care. In adults difference is significant (p \"\" 0.001), In 90
Influence of Leakage from Non-Invasive Positive Pressure Ventilation Mask on FiO2 Value Delivered by Home Oxygen Therapy Concentrator: A Bench Study on Simulating Patients with Chronic Obstructive Pulmonary Disease  [PDF]
Kazuto Doi, Mitsuhiro Nishitani, Mayumi Doi, Yukoh Yaegashi, Masaru Ando, Junichi Kadota
Health (Health) , 2018, DOI: 10.4236/health.2018.107068
Abstract: Introduction: During the application of non-invasive positive pressure ventilation (NPPV) therapy in home mechanical ventilation (HMV), leaks in the NPPV mask may occur owing to the position of the mask due to conditions such as skin disorders. Methods: To investigate whether such a leak affects FiO2 supplied to the alveoli, we simulated a patient with chronic obstructive pulmonary disorder during NPPV in HMV. In addition, FiO2 was measured in the portion assumed to be the mouth and lungs while setting the flow of the oxygen concentrator and leak amount based on a previous study. Results: FiO2 supplied to the lungs increased statistically significantly upon increasing the amount of leak (P < 0.001). Moreover, values measured for the mouth were similar. However, our results were different from those of a previous study. Conclusions: We observed that FiO2 supplied to alveoli can be reduced by a leak in the NPPV mask. Because our results differ from those previously reported, we believe that further studies should reassess the selection of respirators and oxygen concentrators.
Mechanisms of Mycotoxin-Induced Neurotoxicity through Oxidative Stress-Associated Pathways
Kunio Doi,Koji Uetsuka
International Journal of Molecular Sciences , 2011, DOI: 10.3390/ijms12085213
Abstract: Among many mycotoxins, T-2 toxin, macrocyclic trichothecenes, fumonisin B 1 (FB 1) and ochratochin A (OTA) are known to have the potential to induce neurotoxicity in rodent models. T-2 toxin induces neuronal cell apoptosis in the fetal and adult brain. Macrocyclic trichothecenes bring about neuronal cell apoptosis and inflammation in the olfactory epithelium and olfactory bulb. FB 1 induces neuronal degeneration in the cerebral cortex, concurrent with disruption of de novo ceramide synthesis. OTA causes acute depletion of striatal dopamine and its metabolites, accompanying evidence of neuronal cell apoptosis in the substantia nigra, striatum and hippocampus. This paper reviews the mechanisms of neurotoxicity induced by these mycotoxins especially from the viewpoint of oxidative stress-associated pathways.
Ikue Doi,Tsunehisa Okuno
Acta Crystallographica Section E , 2013, DOI: 10.1107/s1600536812050866
Abstract: In the title molecule, C10H8O2, all non-H atoms are essentailly coplanar (r.m.s. deviation = 0.0192 ), indicating an effective conjugation of the carbonyl group, the benzene ring and the lone pair of the propynyloxy O atom. In the crystal, π–π stacking interactions [centroid–centroid distance = 3.5585 (15) ] connect molecules into inversion dimers which are linked by Csp—H...O=C hydrogen bonds, forming a ladder-like structure.
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