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41.
Peripheral T cell lymphoma encompasses lymphomas with a variety of histologic appearances and clinical patterns. Recently, it has been suggested that almost all of the histologic features described under the name of polymorphic reticulosis(PR), lethal midline granuloma, and midline malignant reticulosis can be included in those generally described for malignant lymphomas of peripheral T cell origin(PTCL). There have been few studies of pathogenesis or tissue damage mechanism in PR patients. The need for a precise mechanism for tissue damage has important therapeutic implications. Using immunohistochemical methods with polyclonal anti IL-6 antibody, the authors describe 5 cases of PR with clinically and pathologically typical PR demonstrating a high expression of IL-6. According to classification, 2 cases of grade 1 PR showed the highest expressions, and 2 cases of grade 2 PR with atypical lymphoid cells showed moderate activity, but one case progressed into frank lymphoma(grade 3) and lost IL-6 expression. This strongly implies that some cases of PR have a different mechanism of tissue damage from frank PTCL, despite the one disease spectrum. Further studies on more cases may help clarify the pathogenesis. 相似文献
42.
A new technique is presented for the problem of linearly constrained multi-channel-array processing. The purpose of the array processing is to reject undesired noise, in the minimum-mean-squared-error sense, while responding to any signal coming from a particular direction with a preset, constrained frequency response. In the constraint-elimination technique proposed in this paper, the original constrained-array-processing problem is transformed to the simple unconstrained-Wiener-filtering problem. Transformation of the problem is achieved by introducing a ?compensating? channel to the multichannel processor. Input to the compensating channel is the channel-averaged input. The constraint is then eliminated by expressing the filter weights of the compensating channel in terms of those of the original processor. An adaptive algorithm is derived by applying the stochastic approximation to the simplified Wiener-filtering problem. Simulation experiments verify that the constrained-array-processing problem is properly transformed to the unconstrained one by the proposed technique. Additional experiments show that the adaptive algorithm generally reduces output power while maintaining the constrained frequency response to the desired signal. 相似文献
43.
Effects of gamma irradiation on the color characteristic and biological activities of methanol and acetone extracts of Lonicera japonica (Japanese honeysuckle) irradiated at 0, 10, 20, and 30 kGy were investigated. Hunter color L*- and a*-value increased by irradiation in a dose-dependent manner, resulting in it being lighter than the nonirradiated, while Hunter color b*-values decreased by irradiation (P<0.05). The extracts from L. japonica showed an inhibition effect against tyrosinase, xanthine oxidase and the nitrite scavenging ability. Tyrosinase inhibition effect of L. japonica was higher in the irradiated sample than the nonirradiated, and the effect was increased by irradiation doses. The L. japonica extracts had a higher inhibitory effect against xanthine oxidase, and the effect was not changed by irradiation. Nitrite scavenging activity was the highest in L. japonica extract at pH 1.2. The difference between solvents used was not detected. Thus, gamma irradiation may have no influence on the biological activities of the L. japonica extracts except for the tyrosinase inhibition effect when irradiated up to 30 kGy. 相似文献
44.
Changjin?LeeEmail author Jae-Woo?Lee Do-Young?Byun 《Journal of Mechanical Science and Technology》2003,17(10):1572-1582
Hybrid rocket combustion has a manifestation of stable response to the perturbations compared to solid propellant combustion.
Recently, it has revealed that the low frequency combustion instability about 10 Hz was occurred mainly due to thermal inertia
of solid fuel. In this paper. the combustion response function was theoretically derived by use of ZN (Zeldovich-Novozhilov)
method. The result with HTPB/LOX combination showed a quite good agreement in response function with previous works and could
predict the low frequency oscillations with a peak around 10 Hz which was observed experimentally. Also, it was found that
the amplification region in the frequency domain is independent of the regression rate exponentn but showed the dependence of activation energy. Moreover, the response function has shown that the hybrid combustion system
was stable due to negative heat release of solid fuel for vaporization, even though the addition of energetic ingredients
such as AP and Al could lead to increase heat release at the fuel surface. 相似文献
45.
Jong Hoo Paik Sahn Nahm Young Sik Kim Hyun Min Park Hwack Joo Lee Jae Dong Byun 《Journal of Materials Science》2003,38(3):621-628
The crystal structure of (Ba1–x
La
x
)[Mg(1 + x)/3Nb(2–x)/3]O3 (BLMN) ceramics with 0 x 1 was investigated using X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). When the La content, x, was above 0.1, the 1:2 ordered hexagonal structure found in Ba(Mg1/3Nb2/3)O3 (BMN) was transformed into the 1:1 ordered cubic structure. The 1:1 ordered cubic structure was maintained up to x = 0.7. When x exceeded 0.7, however, BLMN exhibited a 1:1 ordered monoclinic structure, rather than a 1:1 ordered cubic structure. La(Mg2/3Nb1/3)O3 (LMN) has a 1:1 ordered monoclinic P21/n structure with a = 5.6004 Å, b = 5.6414 Å, c = 7.9346 Å, and = 89.9819°. The monoclinic LMN has the in-phase and the anti-phase tilt of oxygen octahedra. The anti-parallel shift of A-site cations was also found in LMN. 相似文献
46.
J. Grinyer J. Atanackovic S.H. Byun D.R. Chettle 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,263(1):262-265
Prompt gamma neutron activation analysis is a means of non-invasive monitoring for occupational exposure to toxic heavy metals such as Cd and Hg. Preliminary kidney detection limits from previous phantom studies at McMaster were 13.6 ± 0.2 ppm for Cd (125 mL phantom) and 315 ± 24 ppm for Hg (125 mL phantom) using the 238Pu-Be neutron source and 0.88 ± 0.01 ppm for Cd (125 mL phantom) and 16.91 ± 0.05 ppm for Hg (30 mL phantom) using the thermal neutron beam port at the McMaster Nuclear Reactor. The detection limits vary greatly between the two methods due to differences in experimental set-up, neutron energy spectra and a difference in dose by more than a factor of 100. The Hg detection limit from preliminary data is much higher than expected for both neutron source types. In order to explain the apparent detection limit discrepancy, measurements of Hg and Cd phantoms were performed using the 238Pu-Be neutron source. The results were compared to phantom measurements of Cl, a well-known neutron activation element. 相似文献
47.
A Nonconventional Approach to Patterned Nanoarrays of DNA Strands for Template‐Assisted Assembly of Polyfluorene Nanowires 下载免费PDF全文
Dong Geun Bae Ji‐Eun Jeong Seok Hee Kang Myunghwan Byun Dong‐Wook Han Zhiqun Lin Han Young Woo Suck Won Hong 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(31):4254-4263
DNA molecules have been widely recognized as promising building blocks for constructing functional nanostructures with two main features, that is, self‐assembly and rich chemical functionality. The intrinsic feature size of DNA makes it attractive for creating versatile nanostructures. Moreover, the ease of access to tune the surface of DNA by chemical functionalization offers numerous opportunities for many applications. Herein, a simple yet robust strategy is developed to yield the self‐assembly of DNA by exploiting controlled evaporative assembly of DNA solution in a unique confined geometry. Intriguingly, depending on the concentration of DNA solution, highly aligned nanostructured fibrillar‐like arrays and well‐positioned concentric ring‐like superstructures composed of DNAs are formed. Subsequently, the ring‐like negatively charged DNA superstructures are employed as template to produce conductive organic nanowires on a silicon substrate by complexing with a positively charged conjugated polyelectrolyte poly[9,9‐bis(6′‐N,N,N‐trimethylammoniumhexyl)fluorene dibromide] (PF2) through the strong electrostatic interaction. Finally, a monolithic integration of aligned arrays of DNA‐templated PF2 nanowires to yield two DNA/PF2‐based devices is demonstrated. It is envisioned that this strategy can be readily extended to pattern other biomolecules and may render a broad range of potential applications from the nucleotide sequence and hybridization as recognition events to transducing elements in chemical sensors. 相似文献
48.
This paper presents a new framework for the semi-automatic synthesis of an inhomogeneous texture from a theoretically infinite number of input exemplars. Our algorithm generates a result with natural multiway transitions, maintaining a reasonable synthesis time to keep interactivity. We introduce intermediate textures between multiple exemplars, called ‘transition textures’ which enable our algorithm to produce smooth transitions between input exemplar patches. We also propose ‘image index correction’ to achieve a synthesis speed that is independent of the number of input exemplars by smart placement of transition-texture samples. Our algorithm is semiautomatic, spatially deterministic and well suited to acceleration via parallel processors. Also, our algorithm can easily control the synthesis result to design a texture visual with user interactions. 相似文献
49.
Seong-Gu Hong Thak-Sang Byun Richard A. Lowden Lance L. Snead Yutai Katoh 《Journal of the American Ceramic Society》2007,90(1):184-191
A program to develop new methods to measure the fracture strength of the chemical vapor deposition SiC coatings in nuclear fuel particles has been carried out. Internal pressurization and crush test techniques were developed and applied to prototype-sized tubular and hemispherical shell specimens. The fracture strength measured from each test method applying the Weibull two-parameter distribution, and Weibull parameters were measured. It was shown that data generated with each test technique were independent of the test technique applied. This implies that the developed test methods are reliable and provide reasonable strength data. For the same material, fracture strength varied with the specimen geometry and loading configuration. These size and loading configuration effects on the fracture strength are explained with the concept of effective surface. 相似文献
50.
Sang-Eon Kim Soon-Do Yoon Ki-Pung Yoo Hun-Soo Byun 《Korean Journal of Chemical Engineering》2009,26(1):199-205
Experimental cloud-point data of binary and ternary mixtures for poly(isodecyl methacrylate) [P(IDMA)] in supercritical carbon
dioxide, dimethyl ether (DME), propane, propylene, butane and 1-butene have been studied experimentally using a high pressure
variable volume view cell. These systems show the phase behavior at temperature of 308 K to 473 K and pressure up to 255 MPa.
The cloud-point curves for the P(IDMA)+CO2+isodecyl methacrylate (IDMA) are measured in changes of the pressure-temperature (P-T) slope, and with cosolvent concentrations
of 0-60.1 wt%. Also, experimental data of phase behaviors for IDMA in supercritical carbon dioxide is obtained at temperature
range of 313.2–393.2 K and pressure range of 5.8–22.03 MPa. The experimental results were modeled with the Peng-Robinson equation
of state. The location of the P(IDMA)+CO2 cloud-point curve shifts to lower temperatures and pressures when DME is added to P(IDMA)+CO2 solution. The P(IDMA)+C4 hydrocarbons cloud-point curves are ca. 16.0 MPa lower pressures than the P(IDMA)+C3 hydrocarbons curves at constant temperature.
This article is dedicated to Professor Chul Soo Lee in commemoration of his retirement from Department of Chemical and Biological
Engineering of Korea University. 相似文献