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《考工记·弓人》“往体”、“来体”句错简校读 被引量:1
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作者 闻人军 《自然科学史研究》 CSSCI CSCD 北大核心 2020年第1期24-34,共11页
《考工记·弓人》可能是世上最早的制弓技术文献,其中科技术语“往体”、“来体”分别指弛弦时弓体外挠和张弦时弓体内向。传本《考工记·弓人》曰:“往体多,来体寡,谓之夹臾之属,利射侯与弋。往体寡,来体多,谓之王弓之属,利射... 《考工记·弓人》可能是世上最早的制弓技术文献,其中科技术语“往体”、“来体”分别指弛弦时弓体外挠和张弦时弓体内向。传本《考工记·弓人》曰:“往体多,来体寡,谓之夹臾之属,利射侯与弋。往体寡,来体多,谓之王弓之属,利射革与质。往体、来体若一,谓之唐弓之属,利射深。”然而求证于本书《弓人》节的“析干”之道和“成规”法,他书《周礼·夏官·司弓矢》的六弓次第和沈括《梦溪笔谈·弓有六善》,以及现代射艺知识,理校后发现:“往体多,来体寡”应是“王弓之属”;“往体寡,来体多”反而是“夹臾之属”。由此推测《考工记·弓人》曾经错简,理应校正为“往体多,来体寡,谓之王弓之属,利射革与质。往体寡,来体多,谓之夹臾之属,利射侯与弋。往体、来体若一,谓之唐弓之属,利射深。” 展开更多
关键词 《考工记》 《梦溪笔谈》 弓人 往体
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Motion State Analysis and Seal Ability Study on the Magnetic Fluid Seal of Reciprocating Shaft 被引量:5
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作者 LI De-cai HONG Jian-ping +1 位作者 YANG Qing-xin WANG Xiu-ring 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2002年第2期115-120,共6页
The authors have studied the motion mechanism of the magnetic fluid in a reciprocating seal gap,on the basis of which the authors obtain an anti pressure formula of the reciprocating shaft magnetic fluid seal from gen... The authors have studied the motion mechanism of the magnetic fluid in a reciprocating seal gap,on the basis of which the authors obtain an anti pressure formula of the reciprocating shaft magnetic fluid seal from general Navier Stokes equation.In order to verify the correctness of the anti pressure formula,the authors have calculated the magnetic field distribution of seal structure and have gotten the maximum still anti pressure.Finally,the authors have verified the influence of speed and stroke on the seal anti pressure. 展开更多
关键词 magnetic fluid reciprocating seal anti pressure
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New Media and the Changes in the Communication Paradigm 被引量:1
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《Journalism and Mass Communication》 2013年第5期324-330,共7页
With the emergence of the new digital platforms, a diversified number of approaches and providers cannot damage too much a rather crowded info sphere. What may come as a general challenge is the "performance" amateu... With the emergence of the new digital platforms, a diversified number of approaches and providers cannot damage too much a rather crowded info sphere. What may come as a general challenge is the "performance" amateurs who have the devices, the will but not the skills to become reliable communicators. Good training and an expanded concern for the accuracy of messages should distinguish between fact and fiction, and between information and opinion. The smart phone, the iPod, the lap top, or the tablet has expanded the means of communication. They have also diversified the types of messages circulated. The traditional main stream media outlets are facing a mounting competition from the social networks populated with the folk journalists, albeit, and non-professionals. Basic training of all those willing to come into the communication ring and regulations may concern not only the professionals but also the amateurs, and it may be ways to get over what seems to be a deadlock. 展开更多
关键词 produsers^1 COMMUNICATION digital platforms folk journalism
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Verbal Abuse Russian View
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作者 V. I. Zhelvis 《Journalism and Mass Communication》 2013年第10期645-647,共3页
An important part of human communication--verbal abuse--shows signs of specifically national features. So far the Russian language of law is sadly lacking a few terms necessary in legal procedures concerning cases of ... An important part of human communication--verbal abuse--shows signs of specifically national features. So far the Russian language of law is sadly lacking a few terms necessary in legal procedures concerning cases of human rights violation. The "Westernization" of Russian collectivist mentality makes the solution of the problem still more urgent. 展开更多
关键词 verbal abuse hate speech fighting words HARASSMENT offense INSULT obscenity indecency
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Reducing the Gas Pressure Drop in Suction Mufflers of Hermetic Reciprocating Compressors
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作者 Janatas Ferreira Lacerda Jose Luiz Gasche +1 位作者 Joao Fabio Parise de Lara Danilo Martins Arantes 《Journal of Energy and Power Engineering》 2014年第3期423-430,共8页
The suction muffler of hermetic reciprocating compressors is installed in order to attenuate the noise generated by the gas pulsation of the flow through the suction valve. However, the installation of the suction muf... The suction muffler of hermetic reciprocating compressors is installed in order to attenuate the noise generated by the gas pulsation of the flow through the suction valve. However, the installation of the suction muffler affects the operation of the compressor owing to gas pressure drop, which causes volumetric and energetic efficiency loss due to the gas specific volume augmentation. Therefore, there is a compromise between sound attenuation and pressure drop increase, which has to be taken into account by compressor designers. In this work, it presents a numerical solution to the flow through a suction muffler in order to analyze the pressure field and point out the main contributions to the overall pressure drop of the flow. A commercial CFD (computational fluid dynamics) code was used to perform the numerical simulations and the results were validated by using experimental data. After analyzing the pressure field, the geometry of the muffler was modified intending to decrease the flow pressure drop. The geometric modification produced a 28% reduction on the overall pressure drop, without influencing the sound attenuation. 展开更多
关键词 REFRIGERATION hermetic reciprocating COMPRESSOR muffler.
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α-secretase ADAM IO physically interacts with β-secretase BACE1 in neurons and regulates CHL1 proteolysis 被引量:3
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作者 Xin Wang Congcong Wang Gang Pei 《Journal of Molecular Cell Biology》 SCIE CAS CSCD 2018年第5期411-422,共12页
α-secretase and β-secretase are known to compete for amyloid precursor protein (APP) processing and thus play a vital role in Alzheimer's disease pathogenesis. A disintegrin and metaUoproteinase 10 (ADAM10) and... α-secretase and β-secretase are known to compete for amyloid precursor protein (APP) processing and thus play a vital role in Alzheimer's disease pathogenesis. A disintegrin and metaUoproteinase 10 (ADAM10) and β-site APP cleaving enzyme 1 (BACE1) mediate the major activities of α-secretase and β-secretase in brain and share various common substrates. However, whether they function separately or together is poorly understood. Here, we show that ADAM10 and BACE1 co-localize in the neurites of mouse primary neurons. Co-immunoprecipitation and fluorescence resonance energy transfer analysis revealed that ADAM10 and BACE1 interact with each other under both endogenous and exogenous conditions. In addition, we found that ADAMIO enhances the proteolysis of neural cell adhesion molecule close homolog of L1 (CHL1) by BACE1. Further studies found that ADAM10-BACE1 interaction interfering peptide LT52 attenuates the regulation of ADAM10 on BACEl-mediated cleavage of CHL1. Our data indicate that ADAM10-BACE1 interaction regulates the proteolysis of some specific substrates and may play a potential role in brain function. 展开更多
关键词 SECRETASE Alzheimer's disease ADAM10 BACE1 interact APP CHL1
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Arabidopsis PRK6 interacts specifically with AtRopGEF8/12 and induces depolarized growth of pollen tubes when overexpressed 被引量:8
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作者 Yuexuan Yu Jiali Song +3 位作者 Xiaohui Tian Haiwen Zhang Legong Li Huifen Zhu 《Science China(Life Sciences)》 SCIE CAS CSCD 2018年第1期100-112,共13页
The pollen receptor kinases (PRK) are critical regulators of pollen tube growth. The Arabidopsis genome encodes eight PRK genes, of which six are highly expressed in pollen tubes. The potential functions of AtPRK1 thr... The pollen receptor kinases (PRK) are critical regulators of pollen tube growth. The Arabidopsis genome encodes eight PRK genes, of which six are highly expressed in pollen tubes. The potential functions of AtPRK1 through AtPRK5, but not of AtPRK6,in pollen growth were analyzed in tobacco. Herein, AtPRK6 was cloned, and its function was identified. AtPRK6 was expressed specifically in pollen tubes. A yeast two-hybrid screen of AtPRK6 against 14 Arabidopsis Rop guanine nucleotide exchange factors (RopGEFs) showed that AtPRK6 interacted with AtRopGEF8 and AtRopGEF12. These interactions were confirmed in Arabidopsis mesophyll protoplasts. The interactions between AtPRK6 and AtRopGEF8/12 were mediated by the C-termini of AtRopGEF8/12 and by the juxtamembrane and kinase domain of AtPRK6, but were not dependent on the kinase activity. In addition, transient overexpression of AtPRK6::GFP in Arabidopsis protoplasts revealed that AtPRK6 was localized to the plasma membrane. Tobacco pollen tubes overexpressing AtPRK6 exhibited shorter tubes with enlarged tips. This depolarized tube growth required the kinase domain of AtPRK6 and was not dependent on kinase activity. Taken together, the results show that AtPRK6,through its juxtamembrane and kinase domains (KD), interacts with AtRopGEF8/12 and plays crucial roles in polarized growth of pollen tubes. 展开更多
关键词 pollen receptor kinase pollen tube polarized growth RopGEF Arabidopsis
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Do networks of social interactions reflect patterns of kinship? 被引量:1
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作者 Joah R. MADDEN Johanna F. NIELSEN Tim H. CLUTTON-BROCK 《Current Zoology》 SCIE CAS CSCD 2012年第2期319-328,共10页
The underlying kin structure of groups of animals may be glimpsed from patterns of spatial position or temporal as- sociation between individuals, and is presumed to facilitate inclusive fitness benefits. Such structu... The underlying kin structure of groups of animals may be glimpsed from patterns of spatial position or temporal as- sociation between individuals, and is presumed to facilitate inclusive fitness benefits. Such structure may be evident at a finer, behavioural, scale with individuals preferentially interacting with kin. We tested whether kin structure within groups of meerkats Suricata suricatta matched three forms of social interaction networks: grooming, dominance or foraging competitions. Networks of dominance interactions were positively related to networks of kinship, with close relatives engaging in dominance interactions with each other. This relationship persisted even after excluding the breeding dominant pair and when we restricted the kinship network to only include links between first order kin, which are most likely to be able to discern kin through simple rules of thumb. Conversely, we found no relationship between kinship networks and either grooming networks or networks of foraging competitions. This is surprising because a positive association between kin in a grooming network, or a negative association be- tween kin in a network of foraging competitions offers opportunities for inclusive fitness benefits. Indeed, the positive association between kin in a network of dominance interactions that we did detect does not offer clear inclusive fitness benefits to group members. We conclude that kin structure in behavioural interactions in meerkats may be driven by factors other than indirect fit- ness benefits, and that networks of cooperative behaviours such as grooming may be driven by direct benefits accruing to indi- viduals perhaps through mutualism or manipulation 展开更多
关键词 Social network KINSHIP Social structure GROOMING DOMINANCE MEERKATS
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BED-CEIA估计HIV-1新近感染率的有效性及其影响因素的评价 被引量:8
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作者 马文娟 汪宁 《中华流行病学杂志》 CAS CSCD 北大核心 2010年第9期1056-1061,共6页
在艾滋病流行病学研究中,衡量艾滋病流行趋势最常用的指标是HIV累积感染率和新近感染率.与累积感染率相比,新近感染率对艾滋病流行趋势预测、干预效果评价以及防制策略的制定等能提供更直接的信息.在获取新近感染率的方法中,除了经典的... 在艾滋病流行病学研究中,衡量艾滋病流行趋势最常用的指标是HIV累积感染率和新近感染率.与累积感染率相比,新近感染率对艾滋病流行趋势预测、干预效果评价以及防制策略的制定等能提供更直接的信息.在获取新近感染率的方法中,除了经典的流行病学队列随访方法,目前普遍使用的血清学方法之一是IgG捕获BED酶联免疫法(BED-CEIA).2001年,美国疾病预防控制中心(CDC)艾滋病免疫和诊断室评估了16种基于不同抗体和原理的HIV-1新近感染检测方法,发现新近感染者与既往感染者相比,各种抗体滴度均较低;其中gp41抗体滴度在新近感染者和既往感染者中的差别最大,两者的滴度区间几乎没有重叠,新近感染者的gp41抗体亲和力低于既往感染者,从而认为gp41抗体能够区分新近感染者和既往感染者,并且酶联免疫实验操作相对简单、效果也较理想,因此该室着手开发基于gp41抗体的HIV-1新近感染检测的酶联免疫方法[1]. 展开更多
关键词 IgG捕获BED酶免疫方法 艾滋病毒 新近感染率 评价
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