Presynaptic transporter-mediated release of glutamate evoked by the protonophore FCCP increases under altered gravity conditions

High-affinity Na⁺-dependent glutamate transporters of the plasma membrane mediate the glutamate uptake into neurons, and thus maintain low levels of extracellular glutamate in the synaptic cleft. The study focused on the release of glutamate by reversal of Na⁺-dependent glutamate transporters from rat brain nerve terminals (synaptosomes) under conditions of centrifuge-induced hypergravity. Flow cytometric analysis revealed similarity in the size and cytoplasmic granularity between synaptosomal preparations obtained from control and G-loaded animals (10 G, 1 h). The release of cytosolic l-[¹⁴C]glutamate from synaptosomes was evaluated using the protonophore FCCP, which dissipated synaptic vesicle proton gradient, thus synaptic vesicles were not able to keep glutamate inside and the latter enriched cytosol. FCCP per se induced the greater release of l-[¹⁴C]glutamate in hypergravity as compared to control (4.8 ± 1.0% and 8.0 ± 1.0% of total label). Exocytotic release of l-[¹⁴C]glutamate evoked by depolarization was reduced down to zero after FCCP application under both conditions studied. Depolarization stimulated release of cytosolic l-[¹⁴C]glutamate from synaptosomes preliminary treated with FCCP was considerably increased from 27.0 ± 2.2% of total label in control to 35.0 ± 2.3% in hypergravity. Non-transportable inhibitor of glutamate transporter dl-threo-β-benzyloxyaspartate was found to significantly inhibit high-KCl and FCCP-stimulated release of l-[¹⁴C]glutamate, confirming the release by reversal of glutamate transporters. The enhancement of transporter-mediated release of glutamate in hypergravity was found to result at least partially from the inhibition of the activity of Na/K-ATPase in the plasma membrane of synaptosomes. We suggested that hypergravity-induced alteration in transporter-mediated release of glutamate indicated hypoxic injury of neurons.     

基于能力的工作流任务组织化

为解决一般工作流模型中"活动-成员"的紧耦合链,改进任务分配的柔性和适应性,提出了工作流活动和成员的能力概念.描述了能力本体模型和基于能力的任务组织化原则,建立了"活动-能力-成员"三层结构的过程元模型,给出了一系列能力匹配策略的形式化描述.上述概念和方法在开放边界工作流系统ABCflow中得到应用和验证.      

基于PDCA的EWIS设计质量提升研究与应用

为了全面提升军用飞机线束及线束敷设设计质量,从设计源头根本性改善外场线路问题,从系统设计的角度出发,开展了EWIS (电气线路互联系统)设计质量控制的新流程、新方法和新技术的研究和应用。根据设计质量问题和改进需求分析结果,提出了基于PDCA (质量环)的质量控制方法,并将其应用到实践中,完善了EWIS技术文件体系,形成了EWIS精细化设计及检查验证流程,提高了设计要求的提出、实现、验证和持续完善能力,在此基础上优化了对重量特性的控制过程,极大提高了设计质量和效率,对提升飞机EWIS设计质量具有参考意义。     

考虑易损性的飞机被外爆型武器的毁伤概率

通过对考虑易损性与未考虑易损性的飞机被毁伤概率的比较,表明：在传统的飞机作战效能分析中,飞机被毁伤的概率大多忽略了飞机的易损性,只从攻击飞机的武器性能方面考虑;其实,考虑易损性的飞机被外爆型武器毁伤的概率更切近于实战,易损性对毁伤概率有明显的影响,飞机易损性设计应作为一项非常重要的环节予以重视。     

一种基于UML活动图模型的系统测试方法

UML活动图是基于UML开发的软件设计模型的重要组成部分,它描述了软件系统的动态行为,是软件系统测试过程中的一个重要的信息来源.提出了一个基于UML活动图的场景测试方法,给出了生成基本流和备选流的原则,对传统场景法进行了改进,避免了测试场景集数量爆炸.最后重点结合一个实例对该方法进行了论述.     

军用装备大规模可编程逻辑器件设计计价方法

大规模逻辑编程器件已在军用装备中得到了广泛应用,但目前为止国家还没有相关文件和标准明确其价格评估.长此以往对军用装备的质量必将产生一些不利影响.同时,缺乏科学成本预测工具和价格审核手段的现状,对装备经费资源也会造成很大浪费.根据实际工作经验,分析了影响大规模逻辑编程器件设计价格的主要因素和注意事项,提出了一套大规模逻辑编程的新评估计价方法.     

"神舟三号"大气成分探测器探测结果--2002年4月磁暴期间大气成分的异常变化

"神州三号"(SZ-3)大气成分探测器搭载在SZ-3留轨舱上于2002年3月26日发射入轨,正遇2002年4月发生的连续两次地磁扰动事件,SZ-3大气成分探测器测得了轨道舱运行高度上(330-350 km附近)大气成分的响应变化和异常现象.探测数据表明,在地磁扰动期间,不仅发生了大气中主要成分O和N2的数密度值增变的响应变化,而且在进入地磁扰动峰期开始后6h左右在较高纬度处出现了N2的异常增变和O的异常降变.4-5h后,这种异常增变峰和降变谷由纬度42°N左右逐渐推移向纬度较低地区,直至消失.     

舱外航天服热控系统仿真

针对人体穿着航天服处于过热状态下的散热问题，在分别建立人体热调节系统、金属氢化物冷源和液冷服数学模型的基础上，将3个模型进行结合，对舱外航天服热控系统在5．5h的时间轴上进行综合的仿真计算，求出人体各节段的温度分布情况，液冷服的入口及出口水温，金属氢化物冷源的出口水温等参数，分析航天员的热舒适性，对航天服热控系统的设计有一定的指导作用，并为今后进一步的研究打下了基础．     

Long-term changes in indices of geomagnetic activity at the auroral station Sodankylä

Here we compare the traditional analog measure of geomagnetic activity, Ak, with the more recent digital indices of IHV and Ah based on hourly mean data, and their derivatives at the auroral station Sodankylä. By this selection of indices we study the effects of (i) analog vs. digital technique, and (ii) full local-time vs. local night-time coverage on quantifying local geomagnetic activity. We find that all other indices are stronger than Ak during the low-activity cycles 15–16 suggesting an excess of very low scalings in Ak at this time. The full-day indices consistently depict stronger correlation with the interplanetary magnetic field strength, while the night-time indices have higher correlation with solar wind speed. The Ak index correlates better with the digital indices of full-day coverage than with any night-time index. However, Ak depicts somewhat higher activity levels than the digital full-day indices in the declining phase of the solar cycle, indicating that, due to their different sampling rates, the latter indices are less sensitive to high-frequency variations driven by the Alfvén waves in high-speed streams. On the other hand, the night-time indices have an even stronger response to solar wind speed than Ak. The results strongly indicate that at auroral latitudes, geomagnetic indices with different local time coverage reflect different current systems, which, by an appropriate choice of indices, allows studying the century-scale dynamics of these currents separately.     

A study on possible solar and geomagnetic effects on the precipitation over northwestern Argentina

The precipitation over Tucuman (26.8°S; 65.2°W), which is representative of the Northwestern region of Argentina, is analyzed in search of an association with solar and geomagnetic activity, with the purpose of contributing to the controversial issue on the connection between climate variation and anthropogenic vs. natural forcing. Monthly time series of precipitation, sunspot number (Rz), and aa index were used for the period 1884–2010. A wavelet analysis was performed first which, due to the time series length, shows significant results only for periodicities lower than 32 years. Due to the transient character and non-constant phase of the results, any sustained wavelet coherence between precipitation and either sunspots or aa could be noticed. Moving averages and correlations were also assessed. The 11 and 22-year running mean of precipitation is positively correlated to Rz and aa when the whole period of analysis is considered. However, a shift in the long-term behavior of precipitation is noticed around 1940, which implies different correlation values with Rz and aa when the period before or after this year are considered. The solar cycle length is also considered for this statistical study and partly confirms the results obtained with Rz and aa. We propose plausible physical explanations based on geomagnetic activity and total solar irradiance effects over atmospheric circulation that could support the statistical result. A deeper analysis and broader geographical coverage is needed in order to detect a connection between precipitation and solar variability discernible from greenhouse gases effects. We emphasize the idea of the importance of recognizing and quantifying the different forcing acting on precipitation (or any other climate parameter), which sometimes can be barely evident from a solely statistical analysis.