基于空化流动数值模拟的变螺距诱导轮设计

为了研究变距系数与变螺距诱导轮性能的关系,基于水力计算方法,通过VisualBasic6．0对变螺距诱导轮公式编程,得出3组不同变距系数的诱导轮参数．并采用Fluent软件中的空化流动模型和混合两相流模型,实现了3个变螺距诱导轮模型内流场数值模拟,给出了其内部压力分布以及叶片吸力面空泡体积分布图．通过3组数据的比较,得到其内部流场的主要特征、螺距变化规律与诱导轮性能的关系,发现抗汽蚀性能随着变距系数的增大而变差,同时随着轴向长度的增加,产生的静压值下降．模拟结果表明,模型1抗汽蚀性能和静压值较优,并通过试验验证了配置模型1变螺距诱导轮的泵机组具有较好的抗汽蚀性能．     

变螺距诱导轮对高速离心泵性能及流场的影响研究

为了定量研究诱导轮对高速离心泵内部流场和性能的影响,分别对有诱导轮和无诱导轮的高速离心泵进行三维非定常全流道数值模拟,并获得其压力脉动特性和作用在叶轮上的径向力分布。通过对比分析发现诱导轮产生的扬程提高了叶轮进口压力,从而提升泵的抗汽蚀性能并且能增大泵的扬程,但对效率有一定影响。模拟结果还表明,有、无诱导轮的高速离心泵内压力脉动均主要是由于叶轮和蜗壳动静干涉产生,且主频与叶频相一致,加装诱导轮对泵内的压力脉动频率分布影响较小,幅值在小流量下有所增大而设计流量和大流量下则有所降低。加装诱导轮之后,设计工况和小流量下叶轮受到的径向力的均值与最大值都比无诱导轮模型泵稍大,其中设计工况下均值和最大值分别增大15.13%和18.4%。     

Protein expression of EMMPRIN,MMP-2 and P53 detected by technique of quantum dots immunofluorescence in human lung cancer

AIM: To investigate the expression of extracellular matrix metalloproteinase inducer (EMMPRIN/CD147), matrix metalloproteinase2 (MMP-2) and P53 proteins in human lung cancer tissues and to explore the relationship between EMMPRIN protein and malignant biological behaviour of lung cancer.METHODS: Fluorescent semiconductor nanocrystals were applied, which were nanometer-sized light-emitting particles and were emerging as a new class of fluorescent probes for cancer detection due to the unique optical and electronic properties. The technique of QDs immunofluorescence histochemistry (QDs-IHC) was used to detect the protein expression of EMMPRIN, P53 and MMP-2 in the human lung cancer microarray, and co-expression of EMMPRIN/P53 proteins was also simultaneously detected by double-labeling immunofluorescence.RESULTS: Compared with non-cancerous lung tissues, the positive rates of EMMPRIN, P53 and MMP-2 proteins in the lung cancer tissues were 70.00%, 77.14% and 72.86%, respectively, and the differences were all significant (P<0.05). The positive rates of EMMPRIN, P53 and MMP-2 proteins were all significantly related with tumor staging(TNM stage) and lymph node metastasis (P<0.05). The positive correlation between EMMPRIN expression and protein levels of MMP-2 and P53 was observed (P<0.01).CONCLUSION: The protein expression of EMMPRIN, P53 and MMP-2 is correlated with the development of lung cancer. Malignant progression of lung cancer promoted by EMMPRIN may be closely related with the expression of MMP-2 and P53.     

玉米不同单倍体诱导系之间杂交组合诱导效果的研究

利用3个具有一定亲缘、性状差异的诱导系Stock6改良系、高诱1号和MT041组配成3个诱导系杂交组合:Stock6改良系×高诱1号、Stock6改良系×MT041和高诱1号×MT041,开展其植株生长势(株高)、综合抗性、散粉量、诱导率研究。结果表明,3个诱导系杂交组合在植株生长势(株高)、综合抗性和散粉量等方面均具有超亲的优势;诱导系杂交组合:Stock6改良系×高诱1号和高诱1号×MT041在单倍体诱导率上同样具有超亲的优势;进一步验证表明这二个诱导系杂交组合具有较为稳定的单倍体诱导能力,可作为大规模单倍体育种中诱导花粉源。     

Effects of epithelial cells treated with poly (I:C) on activation of fibroblasts and roles of EMMPRIN

AIM: To investigate the effects of epithelial cells treated with polyinosinic-polycytidylic acid [poly(I:C)] on the proliferation, transdifferentiation and signaling mechanisms of airway fibroblasts.METHODS:Human alveolar epithelial cells were treated with poly(I:C). The cell culture supernatants were used to stimulate the airway fibroblasts or the fibroblasts growing in collagen gels. The proliferation of the fibroblasts, the expression of a-smooth muscle actin (α-SMA) in the fibroblasts and the contractility of the collagen gels containing fibroblasts, as well as the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) were observed. The proliferation of the fibroblasts and the expression levels of α-SMA, MMP-2 and MMP-9 in the fibroblasts stimulated with EMMPRIN were detected. The inhibitors specific for p38 MAPK or ERK1/2 were used to explore the effects on α-SMA expression and EMMPRIN secretion. RESULTS:The culture supernatants of the epithelial cells treated with poly(I:C) induced the proliferation, α-SMA expression and gel contraction as well as EMMPRIN secretion in the fibroblasts. EMMPRIN dose-dependently enhanced fibroblast proliferation, α-SMA expression and activity of MMP-2 and MMP-9. The supernatants of epithelial cells treated with poly(I:C) activated p38 MAPK and ERK1/2 signaling in the fibroblasts, as the specific inhibitors of MAPK or ERK1/2 signaling attenuated the expression of α-SMA and EMMPRIN in the fibroblasts. CONCLUSION: Poly(I:C) induces fibroblast proliferation, α-SMA expression and gel contraction by affecting the process mediated by p38 MAPK and ERK1/2 signaling pathways in epithelial cells. EMMPRIN may be the important media involved in this event.     

寄主诱导剂对大白菜幼苗抗软腐病的诱导效应研究

利用寄主诱导剂处理大白菜幼苗,测定幼苗体内多酚氧化酶(PPO)与苯丙氨酸解氨酶(PAL)的活性,同时测定幼苗体内木质素和总酚含量。结果表明:大白菜幼苗体内PPO与PAL的活性均比对照明显提高(P<0.05),幼苗体内木质素和总酚含量也出现不同程度的累积。诱导剂处理能显著增强大白菜对软腐病的抗性,而且主要是通过提高幼苗体内与抗病性相关的酶的活性以及幼苗体内木质素和总酚含量来实现的。     

玉米单倍体育种技术简介

玉米单倍体育种技术是一种快速获得玉米自交系的新方法,它的显著特点能大大缩短自交系的选育时间。利用常规育种方法一般要经过6～7代(3～4 a时间),而利用单倍体技术只需2代(1 a时间)就可以得到自交系。目前,该项技术在国内的应用还不是很广泛,有许多问题还需要研究探索。从3个方面简要介绍了玉米单倍体育种技术有关程序,包括基础选系材料准备与诱导、单倍体的挑选与加倍、DH系的管理与测配,并就单倍体育种技术未来发展的趋势进行了初步探讨。     

免疫诱抗剂ZNC对水稻的促生增产效果初探

免疫诱抗剂ZNC是一种宛氏拟青霉菌的乙醇提取物,具有促进植物生长、提高植物产量和抗逆性的能力.于水稻苗期和孕穗期喷施不同剂量的ZNC,试验了其对水稻增产抗逆的效果.结果表明,喷施不同浓度ZNC均可以促进水稻生长,其中以浓度为10 ng/mL的处理效果最显著,芽长和根长较对照(不施ZNC)分别增加17.2％和33.7％;...     

水稻品种‘南粳35’辐射诱变突变体的鉴定

利用60Co-γ射线辐照处理无休眠粳稻品种‘南粳35’,对M2代5 238个单株进行田间农艺性状考察和发芽势筛选,并对发芽势和表型与‘南粳35’具有明显差异的材料在M3和M4代进行表型验证和分子标记验证。通过表型验证获得4个休眠性增强的突变体,7 d发芽率约50%～70%,比野生型‘南粳35’的7 d发芽率低30%～50%。获得抽穗期延迟突变体2个,分别在播种(130±1)d和(135±2)d开始抽穗,比‘南粳35’迟抽穗约30和35 d。获得株高突变体1个,其株高为(77.3±2.41)cm,比‘南粳35’矮约25 cm。获得穗顶端退化突变体1个,成熟后其穗长与南粳35穗长差异极显著。获得内稃退化突变体1个,其粒长、粒宽和千粒质量与‘南粳35’差异极显著。获得小粒突变体1个,其在粒长和千粒质量上与‘南粳35’差异极显著。此外,还获得小穗突变体1个,长护颖突变体2个,颖壳开裂突变体4个。选取均匀覆盖12条染色体的129个SSR标记对获得的所有突变体进行分析,以确定这些突变体来源的可靠性。最终,共获得突变体17个,突变频率为0.325%。