GOOSE报文与SCD文件间对应关系的应用研究

面向通用对象的变电站事件（GOOSE）是智能变电站的核心技术。针对GOOSE工作机制与变电站配置文件（SCD）在现场应用中两者关系尚不清晰的问题,首先对SCD中GOOSE相关配置部分的格式、内容予以描述,进而深刻剖析GOOSE的工作机制,并结合某变电站实例详细分析了报文与配置的对应关系。在此基础上提出了与GOOSE相适应的配置方法,以及判别其正确性的手段。最后,现场应用表明本研究有其合理性和有效性。     

抗CD25人鼠嵌合抗体基因真核表达质粒的构建与瞬时表达

目的构建抗CD25人鼠嵌合抗体基因真核表达质粒,并在293T细胞中进行瞬时表达。方法采用RT-PCR技术,设计针对信号肽的简并引物,钓取抗CD25杂交瘤细胞的重、轻链可变区基因,以质粒PAG4622为模板,钓取人抗体IgG1重、轻链恒定区基因,分别将重、轻链可变区基因与相应的恒定区基因进行拼接,将完整的重、轻链嵌合基因分别与真核表达载体pOptiVEC和pcDNA3.3连接,构建抗CD25人鼠嵌合抗体基因真核表达质粒,将其通过脂质体法共转染至293T细胞中进行表达。通过RT-PCR法检测嵌合抗体基因的转录水平,ELISA法检测嵌合抗体的表达量,流式细胞术(FCM)分析嵌合抗体的结合活性。结果抗CD25人鼠嵌合抗体基因真核表达质粒构建正确;RT-PCR显示嵌合抗体基因在293T细胞中成功转录;转染后48、72、96和120h,细胞培养上清中嵌合抗体的含量分别为7.47、11.72、8.02和18.28ng/ml;FCM检测其能特异性与IL-2Rα链结合。结论已成功构建了抗CD25人鼠嵌合抗体基因的真核表达质粒,并能在293T细胞中瞬时表达。     

Experience in design and implementation of an IGES translator

This paper describes a general design concept for an IGES translator. The design allows implementation of IGES translators for different CAD/CAM systems with a minimum of programming effort. It divides the functions of an IGES translator into two categories: those common to implementations of an IGES translator, and those specific to the target system. Allowing user interactions to control entity mappings, the design adds user flexibility to an IGES translator. Different results that can be created for an IGES file are shown and discussed, using a sample implementation.     

Isolation of a CDC25 family gene,MSI2/LTE1, as a multicopy suppressor of ira1

We have identified MS12 as a gene of Saccharomyces cerevisiae which, when on a multicopy vector, suppresses the heat shock sensitivity caused by the loss of the IRA1 product, a negative regulator of the RAS protein. The multicopy MSI2 also suppresses the heat shock sensitivity of cells with the RAS2^val19 mutation but not those with the bcy1 mutation, suggesting that the MSI2 protein may interfere with the activity of the RAS protein. The sequence analysis of MSI2 reveals that it is identical to LTE1 belonging to the CDC25 family: CDC25, SCD25 and BUD5, each of which encodes a guanine nucleotide exchange factor for the ras superfamily gene products. Deletion of the entire MSI2 coding region reveals that MSI2 is not essential but the disruptant shows a cold-sensitive phenotype. Under the non-permissive conditions, more than 70% of the msi2 disruptants arrested at telophase as large budded cells with two nuclei divided completely and elongated spindles, indicating that the msi2 deletion is a cell division cycle mutation. These results suggest that MSI2 is involved in the termination of M phase and that this process is regulated by a ras superfamily gene product.     

Weakly complete problems are not rare

Certain natural decision problems are known to be intractable because they are complete for E, the class of all problems decidable in exponential time. Lutz recently conjectured that many other seemingly intractable problems are not complete for E, but are intractable nonetheless because they areweakly complete for E (i.e., they are in E and hard for more than a measure 0 subset of E). The main result of this paper shows that Lutz's intuition is at least partially correct: many more problems are weakly complete for E than are complete for E.The main result of this paper states that weakly complete problems arenot rare in the sense that they form a non-measure 0 subset of E. This extends a recent result of Lutz that establishes the existence of problems that are weakly complete, but not complete, for E. The proof of Lutz's original result employs a sophisticatedmartingale diagonalization argument. Here, we simplify and extend Lutz's argument to prove the main result. This simplified martingale diagonalization argument may be applicable to other questions involving individual weakly complete problems.     

Evolution of beta-amyloid induced neuropathology: magnetic resonance imaging and anatomical comparisons in the rodent hippocampus

Alzheimer’s disease (AD) is characterized by the anatomical appearance of β-amyloid (βA) plaques and neurofibrillary tangles. These changes are also associated with cyclical inflammation, oxidative damage and, as inferred from the autopsied brains of patients, progressive injury to neurons. Here, we report the short-term effects of an intrahippocampal injection of the toxic βA peptide fragment 25–35 in rats using quantitative magnetic resonance imaging (MRI) methods. Physiological changes within the cornu ammonis 1 (CA1) region of the hippocampus were monitored using a 1.5 T scanner at time points of 0.25, 1 and 24 h, and 7 and 14 days post injection. Spin echo T2-weighted (T2W) and diffusion weighted (DW) images were sequentially acquired. Apparent diffusion coefficients (ADC) were calculated and compared with histological alterations. A significant elevation in mean ADC values (17%) was observed in the ipsilateral CA1 at 14 days. The ADC changes were associated with disrupted pyramidal cells and nuclear lysis observed in histological sections. The contralateral CA1 exhibited a significant decrease in mean ADC of 15% at 14 days post treatment. Histological changes in the contralateral hippocampus suggested decreased neuronal density. T2W maps revealed no significant differences between the active βA 25–35 fragment and its non-active analog, βA 35–25. In conclusion, these results, based on changes in hippocampal ADC, demonstrate that the βA 25–35 treatment induced pathology consistent with edema and cellular necrosis. This is the first report describing the evolution of AD-like pathology in an animal model using DW imaging.     

25钢冷轧球化退火钢带的生产

介绍了涟源钢铁集团有限公司试生产精冲用 2 5钢冷轧球化退火钢带的情况 ,着重分析了其球化退火工艺 ,以及存在的问题。     

真空感应熔炼CuCr25合金氧含量的影响因素

研究了坩埚材料、真空度和合金元素Al对真空感应熔炼CuCr2 5合金氧含量的影响。结果表明 :使用碱性氧化物MgO坩埚制得的CuCr2 5合金的氧含量非常高 ,达到千分之几 ,同时可以引起Cr的偏析。而使用中性氧化物Al2 O3 坩埚后可以完全避免这些问题 ,合金的组织和性能大大改善 ,氧含量降低到 70 0× 10 -6左右 ,如果在此基础上添加适量的脱氧剂Al,则可以制备出性能优异的CuCr2 5触头材料 ,其性能完全达到常规CuCr5 0触头材料的水平。     

Oxidation pretreatment to reduce corrosion of 20%Cr-25%Ni-Nb stainless steel. I. Weight gain and oxide thickness measurements

The improvement in corrosion resistance afforded by a low-pressure selective oxidation pretreatment on 20%Cr–25%Ni-Nb steel is assessed in terms of weight gain and oxide thickness measurements. Both can and sheet specimens were oxidized in a simulated CAGR CO₂ environment at 823, 923, and 1073 K, and gravimetric gross weight-gain measurements were supplemented by spinel and Cr₂O₃ oxide thickness measurements determined by X-ray diffractometry (XRD). The increased protection provided by the pretreatment resulted in a reduction in gross weight gain of 3–4 times at 823 K, two and three times at 923 K, and a somewhat smaller improvement at higher temperatures. The improvement stemmed from the high proportion of Cr₂O₃ selectively formed in the preoxide layer itself. Thermally induced lattice strains in the oxide scale have been assessed from measurements of lattice expansion by XRD.     

25MeVX射线诱发人淋巴细胞染色体畸变剂量效应和相对生物效应(RBE)

本文应用25MeVX射线以不同剂量照射人离体血,诱发淋巴细胞染色体畸变。实验共分析了中期分裂相淋巴细胞4769个。观察到各类染色体畸变适于配不同模式,双着丝粒体,和双着丝粒体+着丝粒环最适于配二次多项方程Y=bD+cD~2;与~(60)Coγ射线比较,相对生物效应RBE值为0.83。