Veno-right ventricular extracorporeal membrane oxygenation for thoracic surgery: an experimental study in dogs

Different photoactivatable derivatives of toxin 3 (CTX) Naja naja siamensis were obtained after CTX reaction with N-hydroxysuccinimide esters of p-azidobenzoic, p-azidotetraflourobenzoic, p-benzoylbenzoic and p-[3-(trifluoromethyl)-3H-diazirin-3-yl]benzoic acids. The ion-exchange HPLC profiles for the reaction products were very similar in four cases, with one predominant peak corresponding to the derivative containing the label at Lys23. After [125I]iodination, CTX photoactivatable derivatives were cross-linked to the nicotinic acetylcholine receptor from Torpedo californica under optimized conditions. The highest cross-linking yield (up to 16% of the bound toxin) was observed for azidobenzoyl-Lys23-CTX. Different receptor subunits were found to be labelled depending on the nature of the photoactivatable group: the azido derivatives labelled the gamma and delta subunits, benzoylbenzoyl derivative labelled the alpha and delta subunits, while p-[3-(trifluoromethyl)-3H-diazirin-3-yl]benzoyl derivative reacted with alpha, gamma and delta subunits. The cross-linking experiments in the presence of varying concentrations of (+)-tubocurarine demonstrated that the Lys23-attached diazirinyl group contacts the delta and alpha subunits in one ligand-binding site, whereas at the other site, for another CTX molecule, the contacts of the Lys23-diazirinyl are with gamma and alpha subunits. This means that the central loop in the two CTX molecules binds at the alpha/gamma and alpha/delta interfaces. Calculation of the sterically possible displacement of diazirinyl nitrogen, basing on the known X-ray structure of CTX, showed that this value does not exceed 13 A. The results obtained favor the disposition of the ligand-binding sites at the subunit interfaces, with the distance between alpha and delta, or alpha and gamma subunits at these sites being not more than 13 A.     

钨带灯的稳定性判据试验

我们通过对国产ＢＷ—１４００型真空钨带灯的稳定性判据进行研究，发现通过钨带灯的电流达到稳定的时间很短（小于５分钟），而钨带灯的灯电阻需要经过２０分钟后才能达到稳定，因此，用电流稳定性作为钨带灯的热平衡判据是不够的，更可靠的判据还应看灯电阻是否达到平衡。     

Ill-conditioned performance functions of queueing systems

Shows that for queueing networks with deterministic or discrete service time distributions, the performance functions can be nondifferentiable at a dense subset of a given interval. The authors also show that when the service time densities are supported on small intervals, the performance function derivatives changes rapidly. The authors prove these results for a two-server cyclic network and then point out a potential generality to other queueing networks. The results indicate that the nonsmooth analysis may be useful in the area of stochastic discrete-event systems     

OPNET环境下的PIM—SM组播路由协议仿真

IPv6组播技术作为下一代互联网的核心技术之一,相对于IPv4组播技术具有更大的优越性。文章首先对PIM-SM组播协议在IPv6上实现PIM-SM涉及的问题进行了论述,然后在OPNET网络仿真模型中实现了对IPv6和IPv4混合网络场景的配置,进行组播的仿真实验比较单播与组播网络的性能,系统地分析了PIM-SM协议在OPNET中的实现。     

基于健康档案的医疗系统PKI信任模型研究

随着医疗信息技术的高速发展,我国医疗信息化建设中的信息安全问题显得越来越重要。而基于电子健康档案的医疗系统中身份认证管理已成为解决医疗信息系统中的安全问题中关键的一环。文章以基于电子健康档案的医疗系统中身份认证机制为出发点,分析PKI中各种信任模型的特点,对现有的方式进行研究和分析,设计出符合适合区域医疗信息平台的PKI信任模型,从而使基于电子健康档案的医疗系统中的身份认证机制更为安全、高效。希望给后续研究这一课题的研究者提供参考。     

MPEG-2／4AAC音频编码模块的验证

先进音频编码（AdvancedAudioCoding,AAC）以其多声道、多采样率、高压缩比、音质好等特点被广泛使用。文中首先介绍了MPEG-2／4AAC音频编码技术;接着基于MPEG-2／4AAC音频编码原理,开发了时钟复位、寄存器配置和音频数据收发的BFM模型,搭建了音频编码模块的RTL级虚拟验证平台,同时归纳了验证项;最后基于此验证平台和验证项,对设计进行了全面的仿真验证。实践证明该验证方法效率高、收敛快、覆盖率高,取得了较好的效果,为后续的FPGA平台验证和芯片应用提供了有力的保证。     

东莞IT企业人才需求调研

采用问卷、访谈调查和文献调查相结合的方法,对东莞IT人才需求状况进行调查研究,得出了东莞IT市场对计算机人才数量、质量、能力等各方面的需求情况,为探索适应东莞经济社会双转型战略背景下的高职计算机专业人才培养提供了参考依据。     

Evaluating Visual Properties via Robust HodgeRank

International Journal of Computer Vision - Nowadays, how to effectively evaluate visual properties has become a popular topic for fine-grained visual comprehension. In this paper we study the...     

Optimizing nonlinearity of piezoresistive pressure sensors by an asymmetric Wheatstone bridge

Microsystem Technologies - Since nonlinearity is critical to silicon piezoresistive pressure sensors, this paper combined theoretical analysis and simulation to study the effect of changing the...