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1.
日本于2009年正式在刑事审判中引入了陪审员制度。但是,陪审员制度的实施却招来了法律界人士和普通民众的反对。这主要是因为陪审员制度存在诸多问题,其实施可能会影响日本刑事法律制度的稳定,并带来新的不公平,同时也会增加民众的负担。因此,制定法律时,一定要考虑本国的实际情况,并做好充分的前期准备。  相似文献   
2.
提出了一种零配置的端到端细粒度追踪的方法-EasyTrace,应用于分布式系统发生性能降级时的问题诊断.传统工具往往存在监测粒度与服务组件源码紧耦合或配置信息复杂、修改代价高等不足,EasyTrace能够做到零配置下性能问题的准确定位.基于开源电子商务系统的实验结果表明,EasyTrace相对传统监测工具对系统造成的扰动很小.  相似文献   
3.
Pressure ulcer is a complex and significant health problem in long-term bedridden patients, and there is currently no effective treatment or efficient prevention method. Furthermore, the molecular mechanisms and pathogenesis contributing to the deep injury of pressure ulcers are unclear. The aim of the study was to explore the role of endoplasmic reticulum (ER) stress and Akt/GSK3β signaling in pressure ulcers. A model of pressure-induced deep tissue injury in adult Sprague-Dawley rats was established. Rats were treated with 2-h compression and subsequent 0.5-h release for various cycles. After recovery, the tissue in the compressed regions was collected for further analysis. The compressed muscle tissues showed clear cellular degenerative features. First, the expression levels of ER stress proteins GRP78, CHOP, and caspase-12 were generally increased compared to those in the control. Phosphorylated Akt and phosphorylated GSK3β were upregulated in the beginning of muscle compression, and immediately significantly decreased at the initiation of ischemia-reperfusion injury in compressed muscles tissue. These data show that ER stress may be involved in the underlying mechanisms of cell degeneration after pressure ulcers and that the Akt/GSK3β signal pathway may play an important role in deep tissue injury induced by pressure and ischemia/reperfusion.  相似文献   
4.
The initiation and propagation behavior of microcracks is closely associated with the cleavage of crystalline materials. We use phase-field-crystal method to explore the evolution process and mechanism of microcracks initiated on grain boundaries (GBs). Constant biaxial strain is applied to the (0001) crystal plane of hexagonal close-packed bicrystal. Under applied strain, cracks are initiated at the end of semi-boundaries between grains. Following this crack initiation (CIN) mechanism, grain boundary misorientation angle (GBMA) can greatly affect the process of crack initiation and propagation (CINPR) in normal GB system. Along with the increase in GBMA, CIN is promoted and the type of subsequent crack propagation changes from trans-granular propagation into inter-granular propagation. System temperature and applied strain also have influence on CINPR. Associated with fracture mechanics theory, the effects of GBMA, temperature and strain on the behavior of CINPR are investigated. Additionally, we give curves of change in free energy to illustrate these effects from energy perspective. Crack arrestment mechanism, especially the plastic relaxation mechanism, is also discussed. The simulation results acquired in this work are in good agreement with theoretical analyses and experimental results.  相似文献   
5.
With high-temperature solid-state reaction method, a series of Lu2Sr(1−x)Al4SiO12:xEu2+ phosphors have been synthesized. With Rietveld refinement method, the crystal structure of Lu2SrAl4SiO12 has been refined. Under the excitation of the ultraviolet and violet band light, Lu2Sr(1−x)Al4SiO12:xEu2+ emits the Eu2+ characteristic blue broadband light. The photoluminescence properties of concentration quenching, emission peak shift, reflectance spectra, and luminescence decay have been investigated. With the structure analyses, the corresponding physical mechanisms have been discussed. With the increased temperature, this phosphor shows well thermal stabilities. For the xEu = 0.06, 0.08, and 0.1 phosphors, the strong anti-thermal quenching performance has been observed. The reason for the anti-thermal quenching of this phosphor has been discussed. The trap capture mechanism may be the suitable physical mechanism to explain the anti-thermal quenching of this phosphor. This phosphor shows the potential applications in the white LED lighting fields.  相似文献   
6.
Direct electrochemistry and electrocatalysis of catalase (Cat) was studied based on a nano-composite film consisting of amine functionalized graphene and gold nanoparticles (AuNPs) modified glassy carbon electrode. Graphene was synthesized chemically by Hummers and Offeman method and then was functionalized with amino groups via chemical modification of carboxyl groups introduced on the graphene surface. The nano-composite film showed an obvious promotion of the direct electron transfer between Cat and the underlying electrode, which attributed to the synergistic effect of graphene-NH2 and AuNPs. The resultant bioelectrode retained its biocatalytic activity and offered fast and sensitive H2O2 quantification. Under the optimized experimental conditions, hydrogen peroxide was detected in the concentration range from 0.3 to 600 μM with a detection limit of 50 nM at S/N = 3. The biosensor exhibited some advantages, such as short time respond (2 s), high sensitivity (13.4 μA/mM) and good reproducibility (RSD = 5.8%).  相似文献   
7.
磷脂是细胞的重要组成成分,对生物体的生长和发育具有重要作用,也是天然的乳化剂、表面活性剂,在食品、医药、化妆品等领域具有广泛的应用。由于每种磷脂分子可以结合不同的脂肪酸,导致磷脂种类繁多且结构复杂,对磷脂的分析比较困难。本文从磷脂的种类及应用、提取纯化、检测方法等方面,对食品中磷脂的研究进展进行概述,比较不同研究方法的优缺点,以期为不同食品中磷脂的深入研究和开发提供参考。  相似文献   
8.
针对辽河油田欢喜岭采油厂地区注水压力高、地层堵塞严重,常规土酸体系解堵效果差且有效期短等问题,用三氯化磷、有机酸和丙酮合成了一种酸化用无氟缓速酸。此缓速酸属有机磷酸类,单独使用不需复配其他HF酸或氟盐即可达到良好的降压增注效果。室内研究表明,60℃下反应48 h时,20%缓速酸溶液的溶蚀率为23.25%,缓速效果好于土酸和氟硼酸。酸液产生沉淀时的pH值为7~8,络合能力为500~600 g/L,可有效防止Fe(OH)3、Al(OH)3等二次沉淀的产生。天然岩心经20%缓速酸处理后的渗透率恢复值为173%,抗压强度损失为22.7%,是土酸处理的0.56倍。将缓速酸体系(20%缓速酸+3%黏土稳定剂BSA-101+0.1%缓蚀剂BSA-602+0.5%助排剂EL-11+0.1%破乳剂YBP-1)在辽河欢喜岭采油厂欢北区块现场应用两口井,注水压力降低5MPa以上,日注水量增加10m3以上。  相似文献   
9.
The hydrolyzate of banana peels containing abundant fermentable sugars as glucose, xylose, mannose, and arabinose was successfully used as a novel substrate for the efficient production of glutathione by Candida utilis SZU 07-01. Xylose was first selected as the sole carbon source for glutathione production, medium optimization for better cell growth and higher glutathione using response surface methodology consisting of PB design, the steepest ascent experiment and CCD was carried out, and the optimal combination of nutrients was obtained as follows: xylose 20 g/L, (NH4)2SO4 9.59 g/L, KH2PO4 3 g/L, L-methionine 5.72 g/L and MgSO4 0.20 g/L. The maximum dry cell weight and glutathione achieved using the optimized medium were 7.36 g/L and 154.32 mg/L, respectively. Following with the content in this medium, other sugars like glucose, mannose and arabinose were chosen as the sole carbon source and all tested available for glutathione production. Based on these results, the hydrolyzate of banana peels was selected as a novel substrate, and a high DCW of 7.68 g/L and glutathione yield of 111.33 mg/L were obtained with the initial sugar concentration of 20 g/L in the hydrolyzate of banana peels.  相似文献   
10.
Recently, considerable attention has been paid to the biologically active of fruit and vegetable processing wastes. In this study, antibacterial properties and major bioactive constituents of Chinese water chestnut peels (CWCP) extracts and fractions were evaluated. The data displayed that ethyl acetate fractions (EF) from CWCP showed greater antibacterial activity than n-butanol fractions, methanol extracts and water fractions against three common foodborne pathogenic bacteria (Staphylococcus aureus, Escherichia coli and Listeria monocytogenes) assessed by the inhibition zone, minimal inhibition concentration and minimal bactericidal concentration values. In accordance with disc diffusion assay, S. aureus was more susceptible to EF than the other two pathogens. Furthermore, action-mode studies indicated that EF exhibited significant bactericidal activity against S. aureus by degrading and disrupting the cell wall and cytoplasmic membrane, ultimately the leakage of cell contents led to cell death. Finally, high-performance liquid chromatography coupled with photodiode array and electrospray ionization mass spectrometry was used for characterization of bioactive constituents in EF, and ten flavonoids aglycons were identified or tentatively identified. The results suggest that the extracts and fractions from CWCP could be potentially used as a possible food supplement to improve food safety by the control or elimination of foodborne pathogenic bacteria.  相似文献   
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