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991.
Shuo Zhang Kexin Guo Hong Han Haiyang Yu Huanhuan Wei Jiangdong Gong Wentao Xu 《Advanced functional materials》2021,31(27):2101917
This paper presents the first synaptic transistor (ST) that combines crossed p-type and n-type semiconductor nanowires (NWs) to form a bipolar conductive channels. The bipolar channel with both electron and hole transport paths enables the emulation of multiplexed neurotransmission of different neurotransmitters in a brain to realize complex neural functions using nanowires. Except for basic synaptic functions, the device demonstrates the potential to distinguish reward-processing and aversive responses. The opposite polarities of NWs enable emulation of a series of complex neural activities using a single electronic device, such as satiety, depression, and drug withdrawal. The device is applicable to deep convolutional neural networks for electrocardiograms. The new strategy of versatile use of electro-hydrodynamically printed NWs (e-NWs) is expected to facilitate emulation of complex neural behaviors, and the realization of future neuromorphic electronics that are capable of these behaviors. 相似文献
992.
本文以厦门大学和香港理工大学校园外部空间为例,通过对比研究将高校外部空间分为环境主导型和建筑主导型两个类型,从空间类型、空间界定方式方面探讨其不同的外部空间特征,分析、总结现代教育中多样化、个性化公共活动所需的外部空间应具有整体性和流动性、与建筑之间联系紧密、具有宜人尺度以及亲近自然。 相似文献
993.
Xiu-Mei Li Jing Liu Yong-Kai Du Zhi-Guo Wen Ji-Tong Wang 《International Journal of Food Properties》2017,20(12):2923-2931
Sonchus brachyotus DC. (S. brachyotus) is considered a vegetable, and rarely considered to be medicinal. However, S. brachyotus is used as a kind of traditional folk herb in Europe. Pharmacological studies are necessary in order to provide a scientific basis to substantiate their use. This study investigated the antimicrobial effect and mechanism of action of the ethanol extract from S. brachyotus. Ethanol extract from S. brachyotus exhibited antimicrobial activity against Escherichia coli, Enterobacter cloacae, Klebsiella pneumonia, Salmonella enteric, Staphylococcus aureus, and Micrococcus luteus; this is especially so in the case of E. coli. This study investigated the novel antibacterial mechanism of ethanol extract from S. brachyotus that shows an apoptosis-like response in E. coli. At all the tested concentration, it was found that ethanol extract from S. brachyotus–treated E. coli cells displayed various apoptotic markers, such as membrane damage, reactive oxygen species accumulation, and membrane depolarization. Expression of caspases protein, which mediates a bacterial apoptosis–like response, was also increased by ethanol extract from S. brachyotus. In order to evaluate the influence of caspases on the appearance of other apoptotic markers, phosphatidylserine exposure and DNA fragmentation were detected and compared with untreated and with ethanol extract from S. brachyotus. These characteristics were detected in E. coli cells, but not in untreated, with ethanol extract from S. brachyotus. In conclusion, the data obtained demonstrated that ethanol extract from S. brachyotus induces an apoptosis-like response in E. coli that associates with caspase-like protein. 相似文献
994.
Na Wang Heya Wang Zhen Weng Cui Zhang Heng Wu Youzhi Guo Zhiyong Sun Weirong Yao 《Journal of surfactants and detergents》2014,17(5):1003-1011
The saponins from the pericarps of Sapindus mukorossi Gaertn. (Sapindaceae) are attracting more and more attention because of their antimicrobial activity and their ability to act as a natural surfactant. However, the color of Sapindus pericarp extract is dark brown, which limits its application in some products. The present study aims to improve the color by adding hydrogen peroxide. An orthogonal L9 (3)4 test design was applied to optimize the decolorization parameters, including the amount of added hydrogen peroxide, time, temperature and pH. The extent of decolorization was up to 89.5 % below 80 °C within 80 min, using 2.5 % hydrogen peroxide at pH 6. The characteristics of Sapindus pericarp extract before and after bleaching were compared, including the antimicrobial and foaming performance, surface activities and detergency properties. There was no significant difference in either the diameters of the inhibition zone or the minimum inhibitory concentration against Candida albicans, Trichophyton rubrum and Pseudomonas aeruginosa (P < 0.05), while these parameters for C. albicans, T. rubrum and P. aeruginosa for the sample after decolorization were 22.33, 25.00, 15.33 mm and 0.91, 0.91, 13.03 mg/mL, respectively. The foamability of the Sapindus pericarp extract after decolorization was somewhat enhanced and the foam stability reduced (P < 0.05). There were no significant differences in values of the critical micelle concentration of the pericarp extract before and after decolorization. The detergency also remained at the same level. Our results show that the properties of the decolorized Sapindus pericarp extract were largely unchanged. This suggests that further development is worthwhile. 相似文献
995.
社会活动的行为主体是由组织机构,包括法人和其他机构,以及自然人组成的。应用以计算机网络为主导的现代信息技术对两大主体的身份进行有效的标识、存储和验证,是信息化条件下政府管理社会和经济活动的必然选择。为此,国务院决定在全国推行统一社会信用代码标识制度。也就是说,社会信用代码统一标识制度,是为了适应市场经济体制和国家信息化建设的需求而设立的一项基本制度,在社会活动中具有重要功能。 相似文献
996.
Based on an offline and online survey of 967 people of Turkish origin living in these countries, we test how legacy and social media have influenced the participation of the members of the Turkish diaspora in Belgium, Germany and the Netherlands in the mid-2013 protests in Turkey’s social movement referred to as Gezi Park. This study also investigates how living in Europe can influence the behavior and attitudes of the sampled individuals from the Turkish Diaspora of Germany, Belgium and Netherlands during the period when the Gezi Park demonstration took place. Our results make it clear that social media were used by those who supported the protest movement, while those who opposed the protest movement primarily used or followed traditional sources of media, including Turkish and European television. Furthermore, supporters amongst the diaspora for the Gezi-protests were primarily active in accruing social capital through bonding and social networking among those who belong to the Turkish diaspora under the guise of the Gezi Park protests. Finally, a significant number of the supporters of the protests in the three countries took part in several different means of supporting the movement, including: disseminating awareness about the Gezi protests through social media, engaging in meetings, and in some cases, even severing contact with friends and acquaintances who did not share their support for the protest movement. 相似文献
997.
以1988年、2002年和2007年遥感影像作为信息源,选择压力—状态—响应(PSR)模型作为研究方法,建立了一套湿地生态环境评价指标体系。通过选取反映压力、状态及响应等方面的指标,在GIS技术的支持下建立了湿地空间信息数据库,对研究区湿地生态环境的动态变化进行分析。结果表明:该时期研究区人为干扰压力不断加强,造成人工湿地增加,天然湿地减少。在1988—2007年期间,研究区天然湿地减少了18 257.4 hm~2,大部分转变成农田和城市、住宅、工交用地。如果按照每年912.87 hm~2的退化速度计算,目前的12.54万hm~2的天然湿地在100年以后将基本消失。特别是近20年以来,研究区湿地内部结构和状态发生显著变化,湿地景观异质性不断增加,破碎化及退化严重。湿地对于人类活动干扰的响应是湿地面积不断减少,人类对于湿地变化的响应是建立湿地保护区。研究成果可为湿地保护、恢复以及城市规划设计等提供科学依据。 相似文献
998.
Recent catastrophic landslides and mitigation in China 总被引:6,自引:0,他引:6
Yueping Yin 《岩石力学与岩土工程学报(英文版)》2011,3(1):10-18
Increasing population density and development of mountainous terrain have brought human settlements within reach of landslide hazards.In recent years,due to the shortening of return period for severe natural events such as heavy rainfall,snowline retreating,great earthquake together with human activities,catastrophic landslides happened more frequently than before,resulting in large-scale casualties due to the increasing occurrences of rapid long-runout rock avalanches,especially in China.This paper present... 相似文献
999.
Family lives and friendships: The perspectives of children in step-, single-parent, and nonstep families. 总被引:1,自引:0,他引:1
Dunn Judy; Davies Lisa C.; O'Connor Thomas G.; Sturgess Wendy 《Canadian Metallurgical Quarterly》2001,15(2):272
Children's reports on their experiences in different family settings (stepfamilies, single-parent families, and intact families), their contact with friends, and the quality of their friendships were studied with data from 238 children drawn from a community sample. A particular focus was on children's confiding and communication: children's recall of communication about family transitions and their current communication about stepfamily issues with family and friends. Friends were found to be key confidants. The relations between children's family lives (confiding, parent–child relationships, family activities, involvement in parental conflict, and communication about stepfamily issues) and their friendships were investigated and found to be linked to biological relatedness and family setting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.