辽东山区生态土地分类中的植物群落数量分析

采用TWINSPAN分类和PCA、CCA排序的方法对辽东山区样方数据进行植物群落数量分析.结果表明;分类和排序是分析植被与环境关系的有效途径.CCA指示了植物群落与环境因子之间的相关关系.MRPP检验表明,特定的植物群落和环境因子的组合是客观存在的,这种特定的组合构成了特定的生态系统单元.本研究共得到6种群落类型,能够基本指示研究区潜在的植被类型,可用于表征生态土地分类中分类单元的植被类型.制约辽东山区森林群落类型、植物种分布格局的主要因素是坡向、坡度的变化,可将其作为生态土地分类的依据.     

烟草调制减害技术的研究进展

烟草调制是烟草生产的关键技术环节之一,调制的优劣不仅直接影响到烟叶的种植效益和品质,也影响烟草有害成分含量的高低。笔者概述了在烟叶调制过程中降低烟草特有亚硝胺（N-TSNAs）和焦油等主要危害物质含量的途径。认为应该扩大和深入在烟草调制过程中减害的研究,重点放在调制过程中参与生物化学和物理方面的因素,实现品质和减害的双重效果。     

Structure and function of antimicrobial peptide penaeidin-5 from the black tiger shrimp Penaeus monodon

The gene for penaeidin-5, an antimicrobial peptide comprising 55 amino acids, was isolated from the hemocyte of black tiger shrimp (Penaeus monodon). RT-PCR expression tests revealed that penaeidin-5 was produced in hemocytes, gills, the intestine and muscle. Western blot analysis confirmed the panaeidin-5 was aboundantin hemocytes, the intestine and hemolymph. Immunohistochemistry revealedpenaeidin-5 in the cuticle and gills that are considered primary defense barriers. The deduced amino acid sequence of penaeidin-5 included a proline-rich N-terminal domain and a carboxyl-domain that contained six cysteine residues. Circular dichrosim analysis revealed an -helix in its secondary structure and the predicted 3D structure indicated two-disulfide bridges in the -helix. Based on the sequence of penaeidin-5 peptide cDNA, synthetic penaeidin-5 was prepared to carry out functional tests. The synthetic peptide had efficient bacteriostatic and bactericidal activity against Aerococcus viridans, and also inhibited the growth of two filamentous fungi, Fusarium pisi and Fusarium oxysporum. To measure penaeidin-5 in vivo, black tiger shrimp were challenged with Vibrio alginolyticus and A. viridans. At 3 h post-challenge, penaeidin-5 was induced and bacterial numbers decreased significantly by 12 h and 24 h.     

Role for the membrane receptor guanylyl cyclase-C in attention deficiency and hyperactive behavior

Midbrain dopamine neurons regulate many important behavioral processes, and their dysfunctions are associated with several human neuropsychiatric disorders such as attention deficit hyperactivity disorder (ADHD) and schizophrenia. Here, we report that these neurons in mice selectively express guanylyl cyclase-C (GC-C), a membrane receptor previously thought to be expressed mainly in the intestine. GC-C activation potentiates the excitatory responses mediated by glutamate and acetylcholine receptors via the activity of guanosine 3',5'-monophosphate-dependent protein kinase (PKG). Mice in which GC-C has been knocked out exhibit hyperactivity and attention deficits. Moreover, their behavioral phenotypes are reversed by ADHD therapeutics and a PKG activator. These results indicate important behavioral and physiological functions for the GC-C/PKG signaling pathway within the brain and suggest new therapeutic targets for neuropsychiatric disorders related to the malfunctions of midbrain dopamine neurons.     

昆明草坪草混播配方优化组合模式探讨

在昆明独特的气候条件下,通过对运动场草坪、观赏草坪和护坡草坪三类草坪混播配方的调查研究,探讨出了适应云南地区种植的9种优化组合。运动场草坪:草地早熟禾(Poa pratensis L.)+高羊茅(Festuca arundinacea Schreb.)+多年生黑麦草(Lolium perenne L.),草地早熟禾+高羊茅,草地早熟禾+狗牙根(Cynodon dactylon(L.)Pers.)+多年生黑麦草;观赏草坪:草地早熟禾+匍匐翦股颖(Agrostis stolonifera L.),草地早熟禾+紫羊茅(Festuca rubra L.),草地早熟禾(优异)+草地早熟禾(蓝月)+草地早熟禾(新哥来得)+草地早熟禾(肯塔基);护坡草坪:高羊茅+多年生黑麦草+狗牙根,高羊茅+多年生黑麦草+狗牙根+白三叶(Trifolium repens L.),高羊茅+多年生黑麦草+狗牙根+白三叶+紫花苜蓿(Medicago sativa L.)。     

3WZ-700型自走式果园风送定向喷雾机

针对现代果园低矮密植的种植特点,设计了3WZ-700型自走式果园风送定向喷雾机。通过理论计算和虚拟样机技术,完成整机结构设计和各关键部件技术参数的确定。设计了适应于低矮密植果园的圆环双流道风送雾化装置,确定叶轮直径0.7 m、出风口宽度0.13 m。实现风机转速0～2 000 r/min的无级变速。田间试验结果表明,树膛内部枝叶正、反面雾滴附着率分别为61.22%、20.90%;树膛外部枝叶正、反面雾滴附着率分别为77.22%、37.17%;作业效率为1.02 hm2/h。     

混合接种Glomus与Pisolithus菌株对尾叶桉矿质营养吸收的影响

对混合接种ＶＡ菌根真菌苏格兰球菌霉和ＥＣＭ真菌彩色豆马勃影响尾叶桉苗期矿质营养元素吸收情况进行了研究。接种苗根真菌对苗木吸收Ｎ、Ｐ、Ｋ和Ｂ产季了较大的影响,主要体现在促进苗木对上述营养元素的吸收和积累。     

临沂市杞柳产业现状及发展对策

概括了临沂杞柳产业发展现状,找出了存在着的杞柳生产不平衡性;杞柳的加工水平有待进一步提高;柳编缺乏品牌意识;柳编产品市场单一;企业管理人员素质偏低等问题。并针对存在的问题,提出了发展对策。     

粮谷中丙线磷残留分析方法

对粮谷中丙线磷残留量的检测，采用新法以甲醇提取样品，经液液萃取净化后，再以气相色谱／氮磷检测器测定，测定低限为０．００５μg/ml的浓度范围内，标准曲线呈良好的线性关系γ＝０．９９６，变异系数为５．８％－７．８％，回收率为７２．０％－１００．２％。取代了常规法的繁锁操作程序，使操作步骤更加简便，分析速度快且灵敏度高，适用范围广。     

家蚕核型多角体病毒p35基因的核苷酸序列分析

对家蚕核型多角体病毒苏州株 (BmNPVsu)p35基因的序列分析表明 :BmNPVsup35编码序列为 897nt,编码 2 98aa。同源性分析表明 :BmNPVsup35与BmNPVT3、AcNPV、SlNPV在核苷酸水平上同源性分别为 99.5%、95.1 %、89.3% ,在氨基酸水平上的同源性分别为 98.7%、89.4 %、76.4 % ,显示了杆状病毒p35基因在进化上的保守性。BmNPVT3中位的N14 6、S2 0 2 、E2 0 4 、K2 4 4 ,在BmNPVsu中分别被G、N、Q、N取代 ,BmNPVT3中S2 2 2 ,在BmNPVsuP35中发生了缺失。推测BmNPVsuP35蛋白的功能及抑制细胞凋亡的能力与BmNPVT3P35蛋白的相似