Phylogenetic,genetic, and phenotypic diversity of Pseudomonas syringae pv. syringae strains isolated from citrus blast and black pit in Tunisia

Citrus blast and black pit caused by Pseudomonas syringae pv. syringae (Pss) is the only bacterial disease reported in Tunisian Citrus orchards. The phylogenetic relationship between Pss strains was studied based on multilocus sequence analysis (MLSA), using partial sequences of housekeeping genes rpoD, rpoB, gyrB, cts, and pfk for 14 representative Pss Citrus strains, including the reference strain LMG5496. The MLSA revealed that the studied Tunisian Citrus strains are closely related to LMG5496 and cluster in phylogroup 02. Based on the cts gene, the majority of Citrus strains clustered in clades “a” and “b”. However, five strains were placed in a newly defined clade “g”. We describe the presence of six different type III secreted effectors (T3SEs). These were found with frequencies of 100% for the effector hopAN1 and the helper hrpK1, 65% for hopT1-2, and 14% for hopN1, hopR1, and hopQ1-2. Investigation of copper resistance showed that 67% of our Pss Citrus strains from Tunisia are resistant to copper sulphate in vitro, and the copper resistance genes copABCDR were detected in 23% of the strains. Our results present new data concerning the genetic diversity and phylogeny, presence of T3SEs, and copper resistance within the Pss populations that affect Citrus in Tunisia.     

SMA智能控制装置及结构地震反应控制分析

为了获得一种性能优良的结构抗震用控制装置,通过利用SMA(Shape Memory Alloy)弹性模量随温度变化特性,设计了一种新型SMA智能控制装置,并给出了SMA智能控制装置最大输出控制力和等效刚度的计算公式。最后,针对某3层框架结构,分别在未控、主动控制和SMA智能控制3种情况下,进行了地震时程仿真分析。计算结果表明:SMA智能控制装置可以有效降低结构地震反应幅值,控制效果接近主动控制效果,是一种较好的结构抗震用控制装置。     

根茬还田刀具火焰喷焊耐磨性的研究

为了解决根茬还田刀具的失效问题,通过正交试验和多因素方差分析,研究了喷焊材料配比、预热温度、乙炔流量、喷涂距离对刀具耐磨性的影响,优化了在根茬还田刀具上喷焊镍基自熔性合金粉(Ni60)与WC粉末的工艺参数:喷焊材料配比为Ni60 35%WC,预热温度为450℃,乙炔流量为1000L/h,喷涂距离为20mm.     

CuO-CG纳米复合材料修饰电极的制备及其在日落黄检测中应用

为预防和避免由滥用日落黄引发的食品安全隐患,建立快速、灵敏、准确测定日落黄的分析方法。该研究基于氧化铜-羧基化石墨烯（Copper Oxide-Carboxylated Graphene,CuO-CG）纳米复合材料修饰电极构建了一种用于日落黄检测的电化学传感器。采用电沉积法制备CuO-CG纳米复合材料修饰电极,利用循环伏安法和计时电流法研究了日落黄在CuO-CG修饰电极上的电化学氧化行为。结果表明：对影响日落黄检测的条件优化后,得出较佳的试验条件为先沉积CG后沉积CuO、CG的沉积时间和沉积电压分别为900 s和-1.4 V、Cu的沉积时间和沉积电压为120 s和-1.1 V、氢氧化钠浓度为0.10 mol/L、计时电流法测定日落黄的施加电压为0.55 V。在优选试验条件下,该电化学传感器对日落黄的响应时间在5 s以内、线性范围为0.20μg/mL～4.07 mg/mL、检出限为79.36 ng/mL。进一步将此传感器用于饮料样品检测,无需复杂的样品处理步骤,测定回收率为99.35%～105.88%。该研究建立的电化学传感器具有响应时间短、线性范围宽、检出限低、重现性好、稳定性佳、选择...     

电机在新能源汽车上的应用

阐述了新能源汽车对驱动电机的性能要求,对常用驱动电机的特点进行了分析,总结了直流电机、交流异步电机、永磁无刷电机和开关磁阻电机各自的优缺点.从国内外以及各类不同新能源汽车的角度研究了目前驱动电机的使用情况,介绍了非晶电机等新型驱动电机并提出了其未来的发展方向.     

Comparative Proteomic Analysis Shows an Elevation of Mdhl Associated with Hepatotoxicity Induced by Copper Nanoparticle in Rats

Copper nanoparticle is a new material widely used in biological medicine, animal husbandry and industrial areas, but its potential toxicity to human health and environment remains unclear. In order to study the hepatotoxic mechanisms of nanoparticles copper, two-dimensional gel electrophoresis （2-DE） and matrix-assisted laser desorption/ionization time of flight mass spectrometry （MALDI/TOF MS） of proteomics technology were used to isolate and identify the differentially expressed proteins from liver, which associated with hepatotoxicity induced by copper nanoparticle in rats. In this study, we have screened 15 kinds of proteins related with hepatotoxicity, of which spot8212 was identified as Malate dehydrogenase （Mdhl）. The mRNA expression trend of Mdhl was consistent with the result of 2-DE by RT-PCR validation. Bioinformatics analysis showed that Mdhl was stable and no signal peptides, subcellular location was in endoplasmic reticulum; it contained many functional sites such as malate dehydrogenase activity signal sites 155LTRLDHNRAKSQI167; a helixes and random coils were the two main elements. Homologous analysis demonstrated high homologous of Mdhl in rats with mouse and human, and the phylogenetic tree of Mdhl was constructed. The result indicated that copper nanoparticle could regulate up the Mdhl protein expression so as to compensate the energy deficit. Energy metabolic disturbance may be a pathway for copper nanoparticle particles to exert the hepatotoxic effects in rats.     

不同化学形式的铜对仔猪生长、消化和胴体组成的影响

１８０头“杜长大”仔猪（２１．３４±０．４４ｋｇ）,按试验要求分为６组,分别饲喂添加５ｍｇ／ｋｇ、５０ｍｇ／ｋｇ、２４０ｍｇ／ｋｇ无机铜（硫酸铜）、５０ｍｇ／ｋｇ酪蛋白铜、５０ｍｇ／ｋｇ奶蛋白铜和５０ｍｇ／ｋｇ大豆蛋白铜的饲粮,试验为期３０天。结果表明：①饲粮中添加不同化学形式的铜均提高了日增重,降低了料重比,其中以５０ｍｇ／ｋｇ酪蛋白铜组最佳,日增重比对照组（５ｍｇ／ｋｇ硫酸铜）提高了１３．６％（Ｐ＜０．０５）,料重比下降了９．５％,其次为２４０ｍｇ／ｋｇ无机铜组,日增重提高了１２．５％（Ｐ＜０．０５）,料重比下降了８．３％（Ｐ＜０．０５）。②添加不同化学形式铜均提高了日粮粗脂肪消化率,其中以２４０ｍｇ／ｋｇ无机铜组最为显著,较对照组提高了３１．０％（Ｐ＜０．０５）,其次为５０ｍｇ／ｋｇ酪蛋白铜组,提高了２９．１％（Ｐ＜０．０５）,但是添加无机铜（硫酸铜）和蛋白铜对干物质和粗蛋白表观消化率均无明显影响。③添加铜对仔猪胴体组成无明显影响,但２４０ｍｇ／ｋｇ无机铜组和酪蛋白铜组肌肉失水率略有升高,色泽呈下降趋势。④２４０ｍｇ／ｋｇ无机铜组和５０ｍｇ／ｋｇ酪蛋白铜组的脑铜含量显著升高,分别较对照组提高了３３．１     

铜在水稻愈伤组织培养中的作用的进一步研究

 以籼稻栽培品种秋桂矮11的愈伤组织为材料,对铜元素的作用作了进一步的研究。在含有2,4-D和脯氨酸的培养基中添加铜元素对愈伤组织的增殖量影响极小,但转移到再分化培养基后这些愈伤组织能再生出显著更多的植株。另一方面,在含有BA、NAA和脯氨酸的培养基中添加铜元素则会由于添加量的不同而产生显著的促进或抑制愈伤组织增殖的作用。然而,不论是增殖受过铜的促进的或者是抑制的愈伤组织,均能在再分化培养基上再生出数量更多和质量更好的植株。     

五种理化因子对眼斑拟石首鱼苗种的影响

报道了眼斑拟石首鱼苗种对盐度、有效氯、高锰酸钾、硫酸铜耐受力的实验,测定了它的呼吸耗氧量和窒息点：缺氧浮头时的溶氧值为1．86mg／L,窒息点范围为0．79～0．38mg／L。实验表明：有效氯毒性极强,高锰酸钾次之,CuSO4·5H2O较弱。采用1×10(－6)以下的CuSO4·5H2O处理眼斑拟石首鱼鱼苗是安全的。     

厚朴中重金属元素镉、铜的含量分析

采用火焰原子吸收方法对4个产区厚朴(浙江、四川、湖南湘西和道县)中的镉(Cd)、铜(Cu)含量进行了测定和分析。测定结果为:铜的平均回收率为96.2%,镉的平均回收率为93.1%。测得结果都符合目前国内外对食品及植物制剂等中重金属含量的规定,并以此对制定厚朴质量相关的控制指标提出了镉含量控制标准由原来的≤0.3μg/g提高到<0.2μg/g,铜的含量控制标准不变的建议。