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排序方式: 共有1503条查询结果,搜索用时 93 毫秒
1.
Asami Nishikori Yoshito Nishimura Rei Shibata Koh-ichi Ohshima Yuka Gion Tomoka Ikeda Midori Filiz Nishimura Tadashi Yoshino Yasuharu Sato 《International journal of molecular sciences》2021,22(8)
Immunoglobulin G4-related disease (IgG4-RD) is a systemic disorder characterized by tissue fibrosis and intense lymphoplasmacytic infiltration, causing progressive organ dysfunction. Activation-induced cytidine deaminase (AID), a deaminase normally expressed in activated B-cells in germinal centers, edits ribonucleotides to induce somatic hypermutation and class switching of immunoglobulin. While AID expression is strictly controlled under physiological conditions, chronic inflammation has been noted to induce its upregulation to propel oncogenesis. We examined AID expression in IgG4-related ophthalmic disease (IgG4-ROD; n = 16), marginal zone lymphoma with IgG4-positive cells (IgG4+ MZL; n = 11), and marginal zone lymphoma without IgG4-positive cells (IgG4- MZL; n = 12) of ocular adnexa using immunohistochemical staining. Immunohistochemistry revealed significantly higher AID-intensity index in IgG4-ROD and IgG4+ MZL than IgG4- MZL (p < 0.001 and = 0.001, respectively). The present results suggest that IgG4-RD has several specific causes of AID up-regulation in addition to inflammation, and AID may be a driver of oncogenesis in IgG4-ROD to IgG4+ MZL. 相似文献
2.
A simple interface fracture test for ceramic environmental barrier coatings (EBCs) on ceramic matrix composites (CMCs) was developed. A variation on the asymmetric double cantilever beam (ADCB) test was proposed so that the interface toughness could be measured in a small specimen of simple shape without applying interlaminar loading to the CMC substrate. The proposed test was applied to an EBC consisting of a mullite layer and Si bond coat on a monolithic SiC substrate. A pre-crack was introduced by pop-in cracking, and then a notch overlapping the pre-crack was machined. The pre-crack was opened by inserting a wedge into the notch. From the critical notch opening displacement the crack starts to propagate, interface toughness is calculated. The measured interface toughness was 4.1?J/m2. Finally, the application range of the test was discussed and suggestions were made for introduction of the notch and pre-crack. 相似文献
3.
Polarity Effect and Electromagnetic Radiation of Partial Discharge Accompanying Growth of Electrical Tree 下载免费PDF全文
Tatsuya Mutakamihigashi Yoshito Kuroishi Hideki Ueno 《Electrical Engineering in Japan》2015,192(3):19-26
We have investigated the characteristics of radiated electromagnetic (EM) waves from positive and negative partial discharges (PD) in epoxy resin and cross‐linked polyethylene. We found that there is a correlation among the EM level from PD, the positive PD current, and electrical trees. Therefore, the growth of an electrical tree produces a lot of positive PD. We have also investigated the characteristics of the frequency region of EM waves from PD in air, insulating oil, and liquid epoxy in addition to the above insulators. EM waves were detected in the frequency region of 40 MHz to 300 MHz from positive and negative PD in epoxy resin and cross‐linked polyethylene. EM waves were also detected in the frequency region of 40 MHz to 150 MHz from positive and negative PD in air. In the case of insulating oil and liquid epoxy, EM waves were detected in the frequency regions of 40 MHz to 150 MHz from positive PD, and 40 MHz to 250 MHz from negative PD. The frequency region differed depending on the material and the discharge polarity. Our investigation indicates that the cause is differences in electric field strength at the time of PD occurrence. 相似文献
4.
5.
Reed (Phragmites australis), a commonly used macrophyte in the wetlands constructed for water purification, was investigated as a new biosorbent for the removal of Cu(2+), Cd(2+), Ni(2+), Pb(2+) and Zn(2+) from aqueous solution. The metal adsorption capacity of reed biomass was improved significantly by water-wash, base- and acid-treatment. The maximum sorption of NaOH-pretreated reed biomass was observed near neutral pH for Cu(2+), Cd(2+), Ni(2+) and Zn(2+), while that for Pb(2+) was from an acidic range of pH 4.0 or higher. The maximum metal adsorption capacity on a molar basis assumed by Langmuir model was in the order of Cu(2+)>Ni(2+)>Cd(2+)>Zn(2+)>Pb(2+). Reed biosorbent showed a very high adsorption affinity value, which helps predict its high ability to adsorb heavy metals at low concentration. Desorption of heavy metals and regeneration of the biosorbent was attained simultaneously by acid elution. Even after three cycles of adsorption-elution, the adsorption capacity was regained completely and the desorption efficiency of metal was maintained at around 90%. 相似文献
6.
One thousand two hundred cycles of accelerated exposure experiment with combined salt water spray simulating atmospheric corrosion was performed for investigating the effect of weld line direction and paint orientation on the corrosion and paint deterioration characteristics of welded part of the steel. The corrosion depth of the weld toe of transverse weld line became 1.35 times as large as that of the base metal part because of the remained salt water on the weld toe. The coating thickness at the weld toe became thin by vertically painting on the transverse weld line. When the scribe line was installed at the thin painted weld toe under the transverse weld line, the paint blister area became 15% larger than that of the base metal part. The paint coating thickness at the weld toe in different weld line directions and paint orientations should be confirmed and ensured from the viewpoints of manufacturing and maintaining steel structures. 相似文献
7.
Hiroshi Isakari Kazuki Niino Hitoshi Yoshikawa Naoshi Nishimura 《International journal for numerical methods in engineering》2012,90(4):484-505
Preconditioning methods based on Calderon's formulae for the periodic fast multipole method for elastodynamics in 3D are investigated. Three different types of formulations are proposed. The first type is a preconditioning just by appropriately ordering the coefficient matrix without multiplying preconditioners. The other two types utilise preconditioners constructed using matrices needed in the main fast multipole method algorithms. We make several numerical experiments with proposed preconditioners to confirm the efficiency of these proposed methods. We also conclude that the preconditioning of the first type is faster with respect to the computational time than other preconditioning methods discussed in this article. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
8.
This paper derives performance limitations for disturbance rejection of scalar systems under information constraints subject to either bounded or Gaussian disturbances. Two kinds of disturbance are treated in a unified manner, using appropriate entropies and distortions. It is shown that the achievable performance cannot be improved even if the maximum information constraint is relaxed to an average information constraint. Another observation is that, while the information constraints are weaker than bit-rate or signal-to-noise ratio constraints on the communication channel, the same performance levels are achieved by the best encoder and decoder for disturbance rejection with the information constraints. 相似文献
9.
This study aims to investigate the shear and tensile impact strength of solder ball attachments. Tests were conducted on Ni-doped and non-Ni-doped Sn-0.7wt.% Cu, Sn-37wt.% Pb and Sn-3.0wt.% Ag-0.7wt.% Cu solder ball grid arrays (BGAs) placed on Cu substrates, which were as-reflowed and aged, over a wide range of displacement rates from 10 to 4000 mm/s in shear and from 1 to 400 mm/s in tensile tests. Ni additions to the Sn-0.7wt.% Cu solders has slowed the growth of the interface intermetallic compounds (IMCs) and made the IMC layer morphology smooth. As-reflowed Ni-doped Sn-0.7wt.% Cu BGA joints show superior properties at high speed shear and tensile impacts compared to the non-Ni-doped Sn-0.7wt.% Cu and Sn-3.0wt.% Ag-0.7wt.% Cu BGAs. Sn-3.0wt.% Ag-0.7wt.% Cu BGAs exhibit the least resistance in both shear and tensile tests among the four compositions of solders, which may result from the cracks in the IMC layers introduced during the reflow processes. 相似文献
10.
The relationship between internal fracture due to high-pressure hydrogen decompression and microstructure of ethylene–propylene–diene–methylene
linkage (EPDM) rubber was investigated by atomic force microscopy (AFM). Nanoscale line-like structures were observed in an
unexposed specimen, and their number and length increased with hydrogen exposure. This result implies that the structure of
the unfilled EPDM rubber is inhomogeneous at a nanoscale level, and nanoscale fracture caused by the bubbles that are formed
from dissolved hydrogen molecules after decompression occurs even though no cracks are observed by optical microscopy. Since
this nanoscale fracture occurred at a threshold tearing energy lower than that obtained from static crack growth tests of
macroscopic cracks (T
s,th), it is supposed that nanoscale structures that fractured at a lower threshold tearing energy (T
nano,th) than T
s,th existed in the rubber matrix, and these low-strength structures were the origin of the nanoscale fracture. From these results,
it is inferred that the fracture of the EPDM rubber by high-pressure hydrogen decompression consists of two fracture processes
that differ in terms of size scale, i.e., bubble formation at a submicrometer level and crack initiation at a micrometer level.
The hydrogen pressures at bubble formation and crack initiation were also estimated by assuming two threshold tearing energies,
T
nano,th for the bubble formation and T
s,th for the crack initiation, in terms of fracture mechanics. As a result, the experimental hydrogen pressures were successfully
estimated. 相似文献