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71.
High-density event-related potentials (ERPs) were measured when participants were required to evaluate oneself, significant others (father and mother) and the most familiar public figures (Lei Feng and Jiang Qing) based on trait adjectives. There were three referential conditions and a non-referential control condition including self-evaluation (SE), significant other-evaluation (SOE), general other-evaluation (GOE), and semantic positivity-evaluation (SPE). The behavioral data showed that RTs to GOE condition were longer than the other three conditions. Scalp ERP analysis revealed that (1) SPE condition elicited a more negative N2 than SE condition, which was associated with inhibition of responses; (2) SE condition elicited a more positive P300 than SPE condition, which was an index of attention to self-relevant stimuli; (3) there was no difference on the amplitude and latency of P300 between SE and SOE conditions, which reflected that the concept of “self” included intimate others (e.g., father and mother) in Chinese culture.  相似文献   
72.
Study Objective: To compare and analyze the changes of the pulmonary-artery pressure of the migrants coming from different elevation in the hypoxic environment of 4636 - 4907 m extreme altitude. To explore the susceptibility to hypoxic pulmonary-artery hypertension (PH) in the subjects from different altitude and profession. Methods: By using Color Doppler Ultmsonography (CDU), measuring the pulmonary-artery pressure of 207 healthy men, who had continuously being lived and worked at the extreme altitude for more than six months, and then were divided into three groups according to their profession and the altitude of original living place. Results: There was a significant difference in the outcomes of pulmonary-artery pressure from the 3 groups. Conclusions: Altitude of original living place, labor intensity are some of factors that impact the pulmonary-artery pressure of the people who exposure to a hypoxic environment. The pulmonary- artery pressure of person without strenuously physical work experience was more sensitive to hypoxic surroundings than that of labor workers. It was not always the fact at an extreme altitude that the moderate altitude mountaineers were superior to other migrants from a lower altitude or plain. The higher PH was found in the groups of the moderate altitude mountaineers and labor workers. It is unlikely certain that one with PH would surfer from HAPE.  相似文献   
73.
上环的若干性质在其对偶中的推广   总被引:2,自引:2,他引:0  
在Brzezinski T(2002)A-上环的基础上介绍了C-环的基本概念,C是一个余代数.分析了C-环及其模范畴的结构,并构造了C-环的例子.研究了C-环中的两个主要函子:忘却函子F:MA→MC和导出函子-□CA:MC→MA.并且讨论了两个函子可分的条件以及这两个函子的伴随情况.其次结合伽罗华理论将上环的一些主要性质推广到C-环,进而得到了C-环中的一些有意义的结论.  相似文献   
74.
75.
Based on high-throughput data, numerous algorithms have been designed to find functions of novel proteins. However, the effectiveness of such algorithms is currently limited by some fundamental factors, including (1) the low a-priori probability of novel proteins participating in a detailed function; (2) the huge false data present in high-throughput datasets; (3) the incomplete data coverage of functional classes; (4) the abundant but heterogeneous negative samples for training the algorithms; and (5) the lack of detailed functional knowledge for training algorithms. Here, for partially characterized proteins, we suggest an approach to finding their finer functions based on protein interaction sub-networks or gene expression patterns, defined in function-specific subspaces. The proposed approach can lessen the above-mentioned problems by properly defining the prediction range and functionally filtering the noisy data, and thus can efficiently find proteins’ novel functions. For thousands of yeast and human proteins partially characterized, it is able to reliably find their finer functions (e.g., the translational functions) with more than 90% precision. The predicted finer functions are highly valuable both for guiding the follow-up wet-lab validation and for providing the necessary data for training algorithms to learn other proteins.  相似文献   
76.
以PVC树脂为原料,采用两个恒温段的程序升温方法加热脱氯制备PVC沥青,并通过空气预氧化法,对所制备的PVC沥青进行了预氧化处理.实验结果表明,PVC树脂在流速为100 mL/min氮气气氛中,以10℃/min速率程序升温至270℃,恒温脱氯150 min后再程序升温至410℃并恒温芳化120 min,可以制备出脱氯率和得率均较高的PVC沥青.该PVC沥青在300℃温度下,采用空气预氧化法预氧化120min,可获得增重率约为11%,氧化交联度较高、耐热性能较好的预氧化PVC沥青.FT-IR光谱分析结果表明,PVC沥青在预氧化的过程中,主要发生了氧化脱氢、脱水、CO2缩聚交联反应,使沥青形成耐热型的氧桥结构,从而达到预氧化目的.  相似文献   
77.
边晶 《长春大学学报》2007,17(10M):70-73
介绍了C语言程序设计中的难点问题——图形打印问题的解决方案,详细论述了如何利用代数方法来解决这一双重循环问题的具体措施。  相似文献   
78.
低碳调质高强度钢中添加硼对焊接冷裂敏感性的影响较少有人研究,并存在两种不同意见.本文对含硼量分别为0.005%,0.0014%,0.0028%,0.0035%的12Ni3CrMoV调质高强度钢焊接冷裂敏感性进行研究.试验结果表明:1.插销试验临界应力:含硼钢比无硼钢(含硼0.0005%)高;含硼钢中,临界应力按含硼量0.0014%,0.0028%,0.0035%的顺序递减.2.扫描电镜断口分析:无硼钢有沿晶断裂区、准介理断裂区和韧窝断裂区.含硼钢没有沿晶断裂区,只有准介理断裂区和韧窝断裂区.3.焊条未烘干时,无硼和含硼钢的插销临界应力都降低,无硼钢沿晶断裂区扩大,含硼钢仍无沿晶断裂区.4.硼在HAZ粗晶区中沿奥氏体晶界形成偏聚带,硼相主要沿奥氏体晶界呈不连续点状析出.含硼愈多,沿奥氏体晶界偏聚和硼相析出也愈多.5.C.D.Beachem提出的断口形貌发展过程示意图可以解释无硼钢断裂,不能完全解释含硼钢断裂过程.6.裂纹敏感性成分Pcm值表达式中,硼项系数为" 5"值得商榷.就本文钢材而言,硼项函数应为"负变数".本文对含硼钢延迟裂纹机理作了探讨.  相似文献   
79.
一种新的基于Kohonen网络的图像矢量量化   总被引:1,自引:0,他引:1  
矢量量化是一种重要的数据压缩方法.本文利用Kohonen自组织映射神经网络进行矢量量化,首次较为详细地讨论了具体实现的步骤与细节,并在此基础上为改善边缘质量,提出一种基于Laplas算子检测边缘弓引导神经网络训练的方法,并通过实验证明其效果是明显的.  相似文献   
80.
本文以 Born-Harb 循环为依据,推导了复合晶体晶格能和与其相应的各二元化合物晶体晶格能之间的关系,并由此给出了复合氧化物晶体晶格能近似计算的新公式。对20种复合氧化物晶体晶格能计算结果的分析表明:用本文所给公式对复合氧化物晶体晶格能进行近似计算是可行的。  相似文献   
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