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1.
CD22 (Siglec-2) is a B-cell surface inhibitory protein capable of selectively recognising sialylated glycans, thus dampening autoimmune responses against self-antigens. Here we have characterised the dynamic recognition of complex-type N-glycans by human CD22 by means of orthogonal approaches including NMR spectroscopy, computational methods and biophysical assays. We provide new molecular insights into the binding mode of sialoglycans in complex with h-CD22, highlighting the role of the sialic acid galactose moieties in the recognition process, elucidating the conformational behaviour of complex-type N-glycans bound to Siglec-2 and dissecting the formation of CD22 homo-oligomers on the B-cell surface. Our results could enable the development of additional therapeutics capable of modulating the activity of h-CD22 in autoimmune diseases and malignancies derived from B-cells.  相似文献   
2.
This paper reported an effectiveness of pre-cold rolling-induced{332}\113[twins combined with subsequent isothermal x-phase formation for enhancement of uniform elongation in a b-type Ti–15Mo alloy with high yield strength level.Mechanical{332}\113[twins were induced by cold rolling with an thickness reduction of 5%,which had little effect on x-phase precipitation after aging at 573 K for 3.6 ks.Twinning after the cold rolling was further activated during tensile deformation,even with the presence of isothermal x-phase.This combination of twins and x-phase enhanced uniform elongation from 0 to 9%at yield strength level of 890 MPa.The high yield strength was mainly dominated by dislocation slip due to the isothermal x-phase formation,and early onset of plastic instability after yielding was hindered due to the pre-cold rolling-induced twins.Dynamic microstructural refinement was induced by further twinning activation during deformation,which resulted in high work hardening rate corresponding enhancement of uniform elongation.  相似文献   
3.
Monitoring the temperature in liquid hydrogen (LH2) storage tanks on ships is important for the safety of maritime navigation. In addition, accurate temperature measurement is also required for commercial transactions. Temperature and pressure define the density of liquid hydrogen, which is directly linked to trading interests. In this study, we developed and tested a liquid hydrogen temperature monitoring system that uses platinum resistance sensors with a nominal electrical resistance of approximately 1000 Ω at room temperature, PT-1000, for marine applications. The temperature measurements were carried out using a newly developed temperature monitoring system under different pressure conditions. The measured values are compared with a calibrated reference PT-1000 resistance thermometer. We confirm a measurement accuracy of ±50 mK in a pressure range of 0.1 MPa–0.5 MPa.  相似文献   
4.
Although hydrogen refueling stations (HRSs) are becoming widespread across Japan and are essential for the operation of fuel cell vehicles, they present potential hazards. A large number of accidents such as explosions or fires have been reported, rendering it necessary to conduct a number of qualitative and quantitative risk assessments for HRSs. Current safety codes and technical standards related to Japanese HRSs have been established based on the results of a qualitative risk assessment and quantitative effectiveness validation of safety measures over ten years ago. In the last decade, there has been much development in the technologies of the components or facilities used in domestic HRSs and much operational experience as well as knowledge to use hydrogen in HRSs safely have been gained through years of commercial operation. The purpose of the present study is to conduct a quantitative risk assessment (QRA) of the latest HRS model representing Japanese HRSs with the most current information and to identify the most significant scenarios that pose the greatest risks to the physical surroundings in the HRS model. The results of the QRA show that the risk contours of 10?3 and 10?4 per year were confined within the HRS boundaries, whereas the risk contours of 10?5 and 10?6 per year are still present outside the HRS. Comparing the breakdown of the individual risks (IRs) at the risk ranking points, we conclude that the risk of jet fire demonstrates the highest contribution to the risks at all of the risk ranking points and outside the station. To reduce these risks and confine the risk contour of 10?6 per year within the HRS boundaries, it is necessary to consider risk mitigation measures for jet fires.  相似文献   
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ABSTRACT

A deformable gel-packed chromatographic column was used to separate as-synthesized graphite oxide with different sizes. The synthesized gel (56 µm) was deformed by pressure of the fluid flow and the gaps in the gels showed a range of sizes. A suspension of graphene oxide (0.1 g/L, 10 mL) was injected, and graphene oxide in the elution had a size at 0.56 μm and 0.14 μm, whereas in half upper and bottom domain of the gel layer graphene oxide had a size at 33 µm and 2.9 µm, respectively, demonstrating that graphene oxide suspension was separated by size through gel layer.  相似文献   
7.
The ability of Clostridium butyricum RAK25832 to use casamino acids as a nitrogen source was investigated. Strain RAK25832 showed the capacity to utilize different types of carbon sources. With glucose as a carbon source (10 g/L), the preferred final concentration of casamino acids was 26.67 g/L, with a cumulative hydrogen production, production rate, and yield of 2505 mL H2/L, 160 mL/h, and 1.81 mol H2/mol glucose, respectively. Eighteen metal elements were screened to identify the most important metals for biohydrogen production, and four elements were optimized. The optimal medium composition was MgCl2·6H2O (0.1 g/L), K2HPO4·3H2O (6.67 g/L), NaHCO3 (2.6 g/L), and FeCl2·4H2O (0.002 g/L). Vitamin supplementation of the medium showed no significant effect on hydrogen production. Under the optimized conditions, cumulative hydrogen production reached 3074 mL H2/L. This is the first study to demonstrate the use of casamino acids as a nitrogen source by C. butyricum.  相似文献   
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美国国家环保局(USEPA)制定并发布的1623方法是目前国际上常用的水中隐孢子虫和贾第鞭毛虫标准检测方法,该方法存在成本高、回收率低等缺陷。各国研究者试图通过考察其他水质指标与两虫的相关关系来寻找两虫密度和活性的有效替代指标,以间接反映两虫在水体中的存在水平,其中包括浊度、颗粒计数等物理学指标以及细菌、细菌孢子、病毒、噬菌体等生物学指标。虽然还未得出具有普遍性的结论,但研究表明颗粒计数、好氧孢子等有可能成为有效的两虫替代指标。  相似文献   
10.
典型含氮有机物的氯消毒副产物生成潜能研究   总被引:6,自引:1,他引:6  
污水再生利用是解决我国城市水资源短缺的有效途径,消毒是保证再生水水质安全的必要措施。氯消毒可以有效杀灭病原微生物,但同时也会生成各种具有毒性和“三致”效应的消毒副产物。由于含氮有机物是污水氯消毒副产物的一类重要前体物,故选取20种基本氨基酸为研究对象,考察了它们经氯消毒后生成三氯甲烷、卤乙酸、卤乙腈、三氯硝基甲烷、1,1-二氯-2-丙酮和1,1,1-三氯-2-丙酮的潜能。结果表明,各种氨基酸的消毒副产物生成潜能与它们的R基结构密切相关,其中R基上带有活性苯环的色氨酸和酪氨酸均表现出了较高的三氯甲烷、卤乙酸和卤乙腈生成潜能。  相似文献   
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