肺缺血再灌注细胞模型的建立及Bag-1表达

目的 建立肺缺血再灌注细胞模型并研究BCL-2结合抗凋亡基因(BCL-2 associated anthanogen-1,Bag-1)在肺缺血再灌注中的表达,以期为研究Bag-1在肺缺血再灌注疾病的作用机制提供实验基础。方法 本课题以A549细胞系作为肺缺血再灌注模型的细胞模型,实验分5组,将A549细胞给予不同缺氧时间:0 h、6 h、12 h、18 h、24 h缺氧,再复氧24 h处理后,通过低温、低氧、葡萄糖剥夺建立缺血再灌注细胞模型。通过比较5组细胞活性、乳酸脱氢酶(lactate dehydrogenase,LDH)以及活性氧自由基(reactive oxygen species,ROS)水平,确定建模效果,同时观察Bag在肺缺血再灌注中的表达。结果 不同缺氧时间处理后,缺氧组细胞活性均较正常组细胞活性降低(P<0.01),并随缺氧时间延长细胞活性下降,各时间点间细胞活性存在显著差异(F=85.03,P<0.001)。缺氧组LDH、ROS浓度均较正常组细胞明显升高(P<0.01),各时间点间LDH(F=107.67,P<0.001)、ROS(F=42.61,P<0.001)水平具有统计学意义,Bag-1表达在缺氧6 h时最高,后随时间延长水平逐渐下降。结论 以A549细胞系作为模型细胞,以低温、低氧、葡萄糖剥夺为方法可成功建立缺血再灌注细胞模型,Bag-1在缺血再灌注损伤中表达趋势为先升高,再降低。

含BAG-nMgO的新型牙科复合树脂的抗菌及再矿化性能研究

目的:联合应用生物活性玻璃(BAG)和纳米氧化镁(nMgO)改性牙科光固化复合树脂,以获得兼备优良的抗菌性及再矿化性能的新型牙科复合树脂。方法:将不同含量的BAG(2.5 wt%、7.5 wt%、12.5 wt%)和2.5 wt%nMgO引入牙科光固化复合树脂中,制备成含BAG-nMgO的实验树脂,并以卡瑞斯玛复合树脂作为对照。通过菌落计数、代谢活性分析(MTT)和活/死细菌染色,评价实验树脂的抗变形链球菌(S.mutans)能力;将脱矿人牙牙本质片及实验树脂在模拟体液(SBF)中浸泡21 d后,通过扫描电子显微镜(SEM)和X射线能谱仪(EDS)观察分析脱矿牙本质表面形貌和元素组成,评估实验树脂再矿化特性;通过万能试验机、维氏硬度仪等测试树脂的固化深度、压缩强度及维氏硬度。结果:实验组树脂的抗S.mutans活性显著高于卡瑞斯玛对照组,且与BAG的含量相关;当BAG添加量为7.5 wt%时,脱矿牙本质开始矿化;BAG添加比例为12.5 wt%时,可见厚的矿化层,牙本质小管几乎被完全封闭;实验组的固化深度均显著高于卡瑞斯玛,维氏硬度优于或与其相近,随着BAG比例的增加,各实验组的固化深度、压缩强度间无显著性差异。结论:BAG和nMgO的联合应用提高了实验树脂的抗菌性,并赋予其再矿化性能。新型复合树脂预期可减少细菌入侵和促进早期龋损的再矿化。本研究为新型多功能复合树脂的研究开发提供了理论依据和研究基础。

基于BS_Bagging-cLightGBM模型的电动汽车故障预测方法

针对因电动汽车故障数据样本类别不平衡引起的机器模型分类性能欠佳、故障查全率低的问题,本文提出一种以LightGBM为基学习器改进的Bagging集成电动汽车故障预测模型:在Bagging集成学习中使用Borderline_SMOTE方法对训练集重新采样,改善训练子集的数据不平衡程度,避免小类样本信息缺失;将权重系数和正则化项嵌入LightGBM基学习器的损失函数中,提高训练中小类样本的错分类代价。实验结果表明,该模型可有效提高故障查全率、宏平均和AUC值,其中AUC值达到0.898 4,故障样本的查全率为0.808 3,在电动汽车不平衡数据集上的故障分类性能显著优于传统单一模型和其他对比算法。

BAG3蛋白在心脏疾病中的研究进展

Bcl-2相关永生基因3(Bcl-2 associated athanogene 3,BAG3)是一种多功能的细胞保护蛋白,也被称为CAIR-1(CAI stressed-1)/Bis(BCL-2 interacting cell death suppressor)。BAG3在心肌和骨骼肌中高表达,发挥多种生理学功能,如维持Z盘的稳定性、减少心肌细胞凋亡,调节蛋白质量控制系统、线粒体稳态以及心肌收缩力等。BAG3和扩张型心肌病、心力衰竭、限制型心肌病、Tako-Tsubo心肌病等多种心脏疾病的发病有关。调控其表达及相关信号通路可能为心脏疾病的诊断和防治提供新的可能性。但目前尚缺少对于BAG3在心脏疾病中的作用的系统阐述。该文综述了BAG3的基本结构和功能,以及相关调控机制,聚焦于BAG3在多种心脏疾病中的作用,以期为疾病的诊断和治疗提供相应的理论支持。

基于BagR-CNN检测模型的物联网网关安全加固方法

物联网(IoT)网关作为多种网络间异构数据传输与交换的关键节点近年来长期遭受大规模攻击,可靠性差,大规模流量处理延时大、抗攻击能力差等问题显著。而现有对物联网网关的可靠性研究主要集中在加密技术和可信认证机制方面,没有解决大规模攻击环境下物联网的可靠性及安全性问题。因此,本文提出了基于BagR-CNN检测模型的物联网网关安全加固方法,设计了可低功耗集成在物联网网关上并能够快速检测出大规模多步骤攻击的模型。首先,不同于传统的单一流量分类,本方法将相关流量聚合到一个包中,并利用基于信息熵相关性的特征增强算法提高检测准确率。其次,区别于传统的特征提取与约简方法,本文提出基于包内相似度的特征扩展方法,挖掘出隐藏的关联信息并能保证包内数据在噪声扰动下的不变性。最后,本文提出基于高斯混合模型(GMM)的特征压缩算法,将聚合包映射为一维向量并由此训练简单的卷积神经网络,以提高检测效率。实验结果表明,基于BagR-CNN检测模型在准确率、召回率和F1值等方面均优于目前对于大规模多步骤攻击的检测方法。同时,在模拟网关上运行时平均CPU利用率(不使用GPU)低于20%,证明该方法适合集成到网关而不影响网关正常的数据传输工作。

基于Bagging混合策略的多风电场稀疏向量自回归概率预测

风电功率预测对电力系统的安全稳定运行具有重要意义。针对多风电场的超短期概率预测问题,提出了一种基于Bagging混合策略和核密度估计(kernel density estimation,KDE)的稀疏向量自回归预测方法。首先通过时间序列分解和余项自举,生成若干自举时间序列。对于每个时间序列,采用向量自回归(vector autoregression,VAR)模型进行预测。针对传统模型在风场数量较多时容易出现的过拟合问题,采用稀疏向量自回归模型,筛选最有效的回归系数,得到稀疏系数矩阵。每个时间序列训练的预测模型分别产生点预测结果,对于多重点预测结果,使用KDE方法产生概率密度的预测结果。在真实风电集群数据上,验证所提多场站概率预测方法的有效性,采用分位数得分评估概率预测精度。相关实验结果表明,该方法可以有效提高概率预测精度。

基于Bagging-异质k近邻的输电电缆故障诊断方法

针对110 kV交叉互联电缆输电线路故障分类不全、分类准确率低等问题。提出了一种基于Bagging-异质k近邻提升学习的交叉互联电缆故障分类方法,首先通过对各类故障得到的主芯及护层电流、电压等相关电气参数归一化处理,构建电气参数特征矩阵;然后基于k近邻(k-NN)算法采用不同k值及不同距离度量作为个体学习器并构建高差子学习器,通过引入Bagging算法提高异质学习器的整体学习效率,可以实现针对不同类型、不同区域交叉互联输电电缆故障的有效区分。该方法相比于传统SVM、k-近邻及逻辑回归等分类方法,降低了多分类误差率及空间复杂度并提高了模型泛化能力,具有较大的工程运用潜力。

The Potential Contribution of Subsurface Drip Irrigation to Water-Saving Agriculture in the Western USA

Water shortages within the western USA are resulting in the adoption of water-saving agricultural practices within this region. Among the many possible methods for saving water in agriculture, the adoption of subsurface drip irrigation （SDI） provides a potential solution to the problem of low water use efficiency. Other advantages of SDI include reduced NO3 leaching compared to surface irrigation, higher yields, a dry soil surface for improved weed control, better crop health, and harvest flexibility for many specialty crops. The use of SDI also allows the virtual elimination of crop water stress, the ability to apply water and nutrients to the most active part of the root zone, protection of drip lines from damage due to cultivation and tillage, and the ability to irrigate with wastewater while preventing human contact. Yet, SDI is used only on a minority of cropland in the arid western USA. Reasons for the limited adoption of SDI include the high initial capital investment required, the need for intensive management, and the urbanization that is rapidly consuming farmland in parts of the western USA. The contributions of SDI to increasing yield, quality, and water use efficiency have been demonstrated. The two major barriers to SDI sustainability in arid regions are economics （i.e., paying for the SDI system）, including the high cost of installation; and salt accumulation, which requires periodic leaching, specialized tillage methods, or transplanting of seedlings rather than direct-seeding. We will review advances in irrigation management with SDI.

The water-saving potential of using micro-sprinkling irrigation for winter wheat production on the North China Plain

The shortage of groundwater resources is a considerable challenge for winter wheat production on the North China Plain.Water-saving technologies and procedures are thus urgently required.To determine the water-saving potential of using micro-sprinkling irrigation(MSI)for winter wheat production,field experiments were conducted from 2012 to 2015.Compared to traditional flooding irrigation(TFI),micro-sprinkling thrice with 90 mm water(MSI1)and micro-sprinkling four times with 120 mm water(MSI2)increased the water use efficiency by 22.5 and 16.2%,respectively,while reducing evapotranspiration by 17.6 and 10.8%.Regardless of the rainfall pattern,MSI(i.e.,MSI1 or MSI2)either stabilized or significantly increased the grain yield,while reducing irrigation water volumes by 20–40%,compared to TFI.Applying the same volumes of irrigation water,MSI(i.e.,MSI3,micro-sprinkling five times with 150 mm water)increased the grain yield and water use efficiency of winter wheat by 4.6 and 11.7%,respectively,compared to TFI.Because MSI could supply irrigation water more frequently in smaller amounts each time,it reduced soil layer compaction,and may have also resulted in a soil water deficit that promoted the spread of roots into the deep soil layer,which is beneficial to photosynthetic production in the critical period.In conclusion,MSI1 or MSI2 either stabilized or significantly increased grain yield while reducing irrigation water volumes by 20–40%compared to TFI,and should provide water-saving technological support in winter wheat production for smallholders on the North China Plain.

Development Potentials and Benefit Analysis of Efficient Water-saving Irrigation in Lixin County

On the basis of analyzing water resources,crop planning structure,and irrigation mode in Lixin County,potentials and benefits of developing efficient water-saving irrigation in the county were explored to provide references for its future water-saving irrigation.

Application Research of Water-saving and Drought-resistant Landscape Plants:A Case Study of Inner Mongolia Drought-resistant Mongolian Grasses

Construction of "water-saving landscape architecture" is a crucial content of building "conservation-minded society'',an important approach of ensuring the sustainable development of landscaping industry.It targets at exploring a reasonable means of using the nature,so as to improve ecological conditions and environment,save resources and energies,and promote the harmonious coexistence of man and nature.Landscape plant is a significant component of landscape architecture,it is a key section to choose proper drought-resistant plant species for the landscape construction.

Analysis on the Water-saving Irrigation Technique Based on the Perspective of Food Safety

The paper analyzed the important role of water saving in protecting the food safety,introduced the present development of agricultural water-saving technique,pointed out the potential risks of water resources,and proposed the future development of water-saving irrigation.

Cotton's Water Demand and Water-Saving Benefits under Drip Irrigation with Plastic Film Mulch

The primary purpose of this research was to give suitable irrigation program according to the growth period and water requirement.A cotton field experiment with mulched drip irrigation was conducted at the National Field Observation and Research Station for Oasis Farmland Ecosystem in Aksu of Xinjiang in 2008.Water balance method was adopted to study the water requirement and water consumption law of cotton under mulched drip irrigation in Tarim Irrigated Area.Statistical analysis of experimental data of irrigation indicates that the relationship between yield of cotton and irrigation presents a quadratic parabola.We fit the model of cotton water production on the basis of field experimental data of cotton.And the analysis on water saving benefit of cotton under mulched drip irrigation was done.Results indicate that water requirements for the irrigated cotton are 543 mm in Tarim Irrigated Area.The water requirements of seedling stage is 252 mm,budding stage is 186 mm,bolling stage is 316 mm and wadding stage is 139 mm.the irrigation amount determines the spatial distribution of soil moisture and water consumption during cotton life cycle.However,water consumption at different growth stages was inconsistent with irrigation.Quantitatively,the water consumed by cotton decreases upon the increase of irrigation amount.From the perspective of water saving,the maximal water use efficiency can reach 3 091 m3/ha.But the highest cotton yield needs 3464 m3/ha irrigation water.In summary,compared to the conventional drip irrigation,a number of benefits in water saving and yield increase were observed when using plastic mulch.At the same amount of irrigation,the cotton yield with plastic mulch was 30.2% higher than conventional approaches,and the efficiency of water utilization increased by30.2%.While at the same yield level,29.3% water was saved by using plastic mulch,and the efficiency increased by 41.5%.

Long-Term No-Tillage Direct Seeding Mode for Water-Saving and Drought-Resistance Rice Production in Rice-Rapeseed Rotation System

To study the effects of long-term no-tillage direct seeding mode on rice yield and the soil physiochemical property in a rice-rapeseed rotation system, a comparative experiment with a water-saving and drought-resistance rice （WDR） variety and a double low rapeseed variety as materials was conducted under no-tillage direct seeding （NTDS） mode and conventional tillage direct seeding （CTDS） mode for four years, using the CTDS mode as the control. Compared with the CTDS mode, the actual rice yield of WDR decreased by 8.10% at the first year, whereas the plant height, spikelet number per panicle, spikelet fertility, 1000-grain weight, grain yield, actual yield, and harvest index increased with no-tillage years, which led to the actual yield increase by 6.49% at the fourth year. Correlation analysis showed that the panicle length was significantly related to the actual yield of WDR. Compared with the CTDS mode in terms of the soil properties, the pH value of the NTDS mode decreased every year, whereas the contents of soil organic matter and total N of the NTDS mode increased. In the 0-5 cm layer of the NTDS mode, the soil bulk decreased, whereas the contents of soil organic matter, total N, and available N increased. In the 5-20 cm layer of the NTDS mode, the available N and K decreased, whereas the soil bulk, contents of soil organic matter, and total N increased. In summary, the NTDS mode increased the rice yield, and could improve the paddy soil fertility of the top layer.

联合自适应邻域和Bagging的协同表示集成学习方法

近年来,协同表示分类(collaborative representation classification,CRC)算法成为高光谱遥感影像分类的研究热点,其中基于bagging的协同表示集成学习算法(bagging-based collaborative representation classification,BagsCRC)利用bagging集成方式有效地提高了基分类器协同表示分类算法的精度。为进一步提升BagsCRC算法的有效性,文章提出了一种联合自适应形状邻域和bagging协同表示集成学习算法(shape-adaptive bagging-based collaborative representation classification,SABagsCRC)。该算法通过构建训练样本和测试样本的自适应形状邻域,进而构建空间信息约束的分类器集成模式。实验采用Indian pines和Washington DC Mall两组高光谱遥感影像,对所提出算法的性能进行了评价。实验结果表明,SABagsCRC算法在分类效果上比BagsCRC算法有明显的提升。

RESEARCH & PRACTICE OF WATER-SAVING AGRICULTURE

China is one of the world’s major agricultural countries. About 80% of its annual water consumption is used for fanning undertakings. On the other hand, China is a country deficient in water resources and in particular, the water shortage is embarrassingly serious in the north. So the current development of water-saving agriculture (WSA) is a way of easing the strain between the supply and demand of water. This article expounds the WSA’s status in the development of the national economy, its research and implementation, and suggests an institutional system of WSA to be established in this country.

Water-saving potential evaluation of water-receiving regions in Shandong province on the East Route of the South-to-North Water Transfer Project of China

Taking 13 water-receiving areas on the East Route of the South-to-North Water Diversion Project(ERSNWDP)in Shandong Province as the study area,and comparing it with Jiangsu Province on the ERSNWDP and the Middle Route of the South-to-North(MRSNWDP),the current water-saving potential of the water-receiving areas within the municipalities of Shandong was analyzed.Different water-saving scenarios were constructed and analyzed with key water-saving indexes in various industries.These indexes include the effective utilization coefficient of farmland irrigation water,total water consumption of industrial sectors with an added value of over 10000 RMB,average leakage rate of the urban public water supply pipe network and the penetration rate of water-saving appliances.Based on the scenarios,comprehensive water-saving potential of the 13 water-receiving area cities was calculated.The results show that the water-saving potential of the study area is at a relative high level.However,some cities still have a certain amount of water-saving potential for agriculture and industry to be elevated.Under the recommended water-saving scenario,the water-saving potential is 1.134 billion m3,accounting for 5.33%of the current total water consumption,of which 460 million m3 is in agriculture,600 million m3 in industry,is and 74.20 million m3 in urban domestic sector.Comprehensive water-saving measures for the study area were proposed from the aspects of agricultural,industrial and domestic water uses.Agricultural and industrial water saving are more significant.The major cities for agricultural water saving include Jining City,Heze City,Weifang City and Jinan City;the focus cities of industrial water saving mainly include Weihai City,Jining City and Qingdao City and etc.;the key water-saving areas for urban use mainly include Zaozhuang City,Jining City and Heze City.

Problems and Development Countermeasures of Agricultural Water-Saving Irrigation

Agriculture is the biggest water user in China,and the development of agricultural water-saving has great significance to the national economy and social development. In this paper,the present situation of water used in agriculture irrigation and water-saving potential were analyzed,and the ＂ bottleneck＂ and main problems existing in water-saving irrigation in China were discussed. From the aspects of engineering investment channels,agricultural water-saving policies and management system,reform of agricultural water price and water right transfer,improvement of farmers＇ water-saving consciousness,and promotion of rural land transfer,suggestions were proposed for the development of China＇s agricultural water-saving in future,which will provide a technical support for the sustainable use of agricultural water resources in China.

Novel Soft ComputingModel for Predicting Blast-Induced Ground Vibration in Open-Pit Mines Based on the Bagging and Sibling of Extra Trees Models

This study considered and predicted blast-induced ground vibration(PPV)in open-pit mines using bagging and sibling techniques under the rigorous combination of machine learning algorithms.Accordingly,four machine learning algorithms,including support vector regression(SVR),extra trees(ExTree),K-nearest neighbors(KNN),and decision tree regression(DTR),were used as the base models for the purposes of combination and PPV initial prediction.The bagging regressor(BA)was then applied to combine these base models with the efforts of variance reduction,overfitting elimination,and generating more robust predictive models,abbreviated as BA-ExTree,BAKNN,BA-SVR,and BA-DTR.It is emphasized that the ExTree model has not been considered for predicting blastinduced ground vibration before,and the bagging of ExTree is an innovation aiming to improve the accuracy of the inherently ExTree model,as well.In addition,two empirical models(i.e.,USBM and Ambraseys)were also treated and compared with the bagging models to gain a comprehensive assessment.With this aim,we collected 300 blasting events with different parameters at the Sin Quyen copper mine(Vietnam),and the produced PPV values were also measured.They were then compiled as the dataset to develop the PPV predictive models.The results revealed that the bagging models provided better performance than the empirical models,except for the BA-DTR model.Of those,the BA-ExTree is the best model with the highest accuracy(i.e.,88.8%).Whereas,the empirical models only provided the accuracy from 73.6%–76%.The details of comparisons and assessments were also presented in this study.

Study on the Suitable Water-Saving Irrigation Technology for Mining Areas in the Northwestern Arid Desert Regions in China

Water is the key factor to ensure plant survival in the process of ecological restoration in the coal base of China northwest deserts. On the premise of meeting the mine production and living water demands, we should take measures such as dirt wastewater treatment and water-saving irrigation to increase income and reduce expenditure and allocate limited water re-sources rationally, to provide mining area ecological restoration maximum usable water resources. The mining dump has large slope and thin soil layer and it is easy to produce surface runoff. So it is particularly important to study the irrigation technology needed to satisfy vegetation restoration, on the premise of guaranteeing not to produce surface runoff and the slope stability. In this paper, through field plot test, the suitable irrigation method for mine slope, slope surface soil moisture migration characteristics and slope stability analysis were studied. Results show that three slope ir-rigation technologies have their own advantages and disadvantages. On the whole, the effect of drip irrigation is the best, micro spray irrigation is the second, infiltrating irrigation is not ideal. The permeability of mine soil slope is very strong, the infiltration rate of the slope direction is the high-est, inverse slope infiltration rate is lowest. In the process of irrigation, with the increase of soil moisture content, slope safety factor is the decreased obviously, the whole slope surface soil moisture content is 14% for the slope stability safety threshold.