黄牛与水牛的毛状肉孢子虫同工酶研究

采用聚丙烯酰胺垂直平板梯度凝胶电泳的方法,对寄生于黄牛和水牛的毛状肉孢子虫进行同工酶比较研究,探讨肉孢子虫的宿主特异性.结果表明黄牛与水牛的毛状肉孢子虫同工酶与工酶谱非常相似,只在活性上略有差异,酶谱存在不同程度的种间差异可作为黄牛与水牛的毛状肉孢子虫同工酶的遗传鉴定标记.从分子水平证明黄牛和水牛都是毛状肉孢子虫自然中间宿主.     

黄牛与水牛的毛状肉孢子虫同工酶研究

采用聚丙蚌酰胺垂直平板梯度凝胶电泳的方法，对寄生于黄牛和水牛的毛状肉孢子虫进行同工酶比较研究，探讨肉孢子虫的宿主特异性。结果表明黄牛与水牛的毛状肉孢子虫同工酶与工酶谱非常相似，只在活性上略有差异，酶谱存在不同程度的种间盖异可作为黄牛与水牛的毛状肉孢子虫同工酶的遗传鉴定标记。从分子水平证明黄牛和水牛都是毛状肉孢子虫自然中间宿主。     

Parasitic Cape honeybee workers, Apis mellifera capensis, evade policing.

Relocation of the Cape honeybee, Apis mellifera capensis, by bee-keepers from southern to northern South Africa in 1990 has caused widespread death of managed African honeybee, A. m. scutellata, colonies. Apis mellifera capensis worker bees are able to lay diploid, female eggs without mating by means of automictic thelytoky (meiosis followed by fusion of two meiotic products to restore egg diploidy), whereas workers of other honeybee subspecies are able to lay only haploid, male eggs. The A. m. capensis workers, which are parasitizing and killing A. m. scutellata colonies in northern South Africa, are the asexual offspring of a single, original worker in which the small amount of genetic variation observed is due to crossing over during meiosis (P. Kryger, personal communication). Here we elucidate two principal mechanisms underlying this parasitism. Parasitic A. m. capensis workers activate their ovaries in host colonies that have a queen present (queenright colonies), and they lay eggs that evade being killed by other workers (worker policing)-the normal fate of worker-laid eggs in colonies with a queen. This unique parasitism by workers is an instance in which a society is unable to control the selfish actions of its members.     

分裂节点法分析虚拟社会网络中的重叠社区

虚拟社会网络分析,尤其是将复杂网络按照连接关联的紧密程度划分为多个集群,是数据挖掘领域的一个研究热点。基于现实社会中成员一般与多个团体相关联这一事实,旨在提出带有重叠集群的抽象网络分割模型及其算法,主要讨论由这一数学模型引出的新问题及基于层次聚类算法提出的解决方案,并且阐述分裂节点法的理论基础、复杂度分析,对比传统算法来证明该方法的优势与不足,及在其他领域的应用价值。     

卷蛾寄蝇族(双翅目:寄蝇科)分类研究(一)

卷蛾寄蝇族昆虫主要寄生于鳞翅目、膜翅目、鞘翅目等昆虫,是重要的农、林业天敌.全世界有243属,约600种,中国有22属66种.以沈阳师范大学昆虫所馆藏各地标本为材料,对该族进行了系统研究.报告7属15种,补充了8个种的省级新分布地,发现2个中国新纪录种:毛奥斯渥寄蝇Oswaldia hirsutaMesnil和银奥斯渥寄蝇O.glaucaShima.     

陕西省被子植物分布新记录及新分类群（Ⅱ）

通过对西北大学生物学系植物标本室收藏标本的研究,发现属于陕西省分布新记录的被子植物２１种、２变种及３新变种,并对它们的名称和分布情况做了报道。     

河南茜草科(Rubiaceae)增补与订正

增补报道了《河南植物志》中未记录的河南产茜草科植物1属、5种、5变种，其中1属（新耳草属Neanotis Lewis）2种（薄叶新耳草Neoatis hirsuta和水团花Adina pilulifera）为河南分布新记录，订正了6个分类群的学名。     

21%Cr铁素体不锈钢成型性能和表面起皱研究

以21%Cr铁素体不锈钢为研究对象,研究了热轧退火及冷轧润滑对带钢中织构和晶粒簇的影响.结果表明:热轧退火再结晶不完全时,成品带钢中心处的晶粒簇明显,且带钢厚度方向上织构梯度很大,使得带钢在成型过程中表面起皱和各向异性明显;冷轧过程不进行润滑时,与采用冷轧润滑的成品带钢相比,带钢厚度方向上的织构梯度增加,γ纤维织构的强度降低,使得带钢的成型性能恶化;当热轧退火使带钢发生完全再结晶,并在冷轧过程中进行充分润滑时,则可使成品带钢同时获得较好的成型性能和抗表面起皱性能.     

T载体的构建及对小麦差异显示片段的克隆

提取克隆转化后蓝白斑菌落中蓝色菌落的质粒用于自行构建T载体,再将小麦差异显示片段克隆到该T载体中进行检验．结果显示,该T载体对PCR产物克隆效率在90％以上,而且使用方便,价格低廉．     

不同杀菌方式对鲜橙汁品质的影响及其感官评价

以鲜榨橙汁为原料,研究了高压脉冲电场(PEF)杀菌技术和热杀菌技术对鲜橙汁中微生物和理化指标的影响,以及鲜橙汁在储藏期间品质变化情况,并对不同杀菌方式所制得的鲜橙汁进行了感官评定.结果 表明:高压脉冲电场可以有效地杀灭鲜橙汁中的微生物,贮藏40 d后,细菌菌落总数和酵母、霉菌菌落总数均符合国家标准;PEF处理的鲜橙汁无论是在色泽、香气还是口感方面都好于热处理的鲜橙汁.     

Parasitoid secretions provoke ant warfare

Insect social parasites are extreme specialists that typically use mimicry or stealth to enter ant colonies to exploit the rich, but fiercely protected, resources within their nests. Here we show how a parasitic wasp (parasitoid) contrives to reach its host, itself an endangered species of social parasite that lives inside the brood chambers of ant nests, by releasing semiochemicals to induce in-fighting between worker ants, locking the colony in combat and leaving it underprotected. Four of these chemicals are new to biology and have the potential to control pest species by inducing different agonistic behaviours in ants.     

豆科树种根瘤菌共生体系的研究——Ⅰ.结瘤观察、分离、回接和交叉接种

<正>对21个豆科树种,包括苏木亚科5个属、含羞草亚科6个属及蝶形花亚科5个属进行了结瘤观察。在田间苗圃及温室盆栽条件下,用未经灭菌的豆科树种根际土壤进行接种,其中只有12种结瘤;苏木亚科5个属的6种全不结瘤,南京常见豆科树种国槐也不结瘤。结瘤豆科树种的根瘤都经分离、纯化。根据对菌落培养性状及菌体形态特征的观察,可见全系典型的根瘤菌;对各原分离树种进行回接试验,进一步确定为各该树种根瘤菌。 9个不同树种根瘤菌经纯培养后,对一些树种进行了广泛的交叉接种试验。接种寄主除各豆科树种外,还包括绿豆、赤豆和豇豆。从所得结果看,大体上可将豆科树种根瘤菌归入豇豆族中。用分离所得的9个豆科树种根瘤菌纯培养的混合菌液在人为条件下接种,自然条件下未见结瘤的苏木亚科各树种和含羞草亚科的孔雀豆仍不结瘤。用2,4-D处理,则根部肿大畸形,甚至形成不规则形状的瘤体,但与真正的根瘤显然不同。观察的21个树种中有4种是首次报道,2种与过去报道的结瘤情况不同。     

喜德县且拖乡花椒高产管理模式研究

喜德县且拖乡现有花椒12.1万株,占全部经济林木的71.2%。发展花椒生产对于解决彝族群众的温饱问题具有重要作用。但长期以来该乡花椒生产中存在椒树寿命短、病虫危害严重、管理水平低等十分突出的问题,并未体现出其应有的经济价值。现结合我校的科技扶贫工作,依据且拖乡的自然、气候条件,提出了以椒、芋间套种植、配方施肥、病虫害综合防治为基本栽培管理措施的高产管理模式。     

《河北植物志》绣线菊属的订正

对《河北植物志》（第１卷）绣线菊属于错误鉴定的美丽线菊、欧亚绣菊和金丝桃叶绣线菊予以订正；把大叶华北绣线菊和小叶华北绣线菊合并；记载了１个新记录变种三裂绣线毛叶变种和１个补充记录种疏毛绣线菊。     

Entomology: Asian honeybees parasitize the future dead

The queen of a honeybee colony has a reproductive monopoly because her workers' ovaries are normally inactive and any eggs that they do lay are eaten by their fellow workers. But if a colony becomes queenless, the workers start to lay eggs, stop policing and rear a last batch of males before the colony finally dies out. Here we show that workers of the Asian dwarf red honeybee Apis florea from other colonies exploit this interval as an opportunity to move in and lay their own eggs while no policing is in force. Such parasitism of queenless colonies does not occur in the western honeybee A. mellifera and may be facilitated by the accessibility of A. florea nests, which are built out in the open.     

Jasmonate and salicylate induce expression of herbivore cytochrome P450 genes

Jasmonate and salicylate are plant-produced signals that activate plant defence genes after herbivory or pathogen attack. Amplification of these signals, evoked by either enemy attack or experimental manipulation, leads to an increase in the synthesis of toxic compounds (allelochemicals) and defence proteins in the plants. Although the jasmonate and salicylate signal cascades activate different sets of plant defence genes, or even act antagonistically, there is substantial communication between the pathways. Jasmonate and salicylate also contribute to protecting plants against herbivores by causing plants that experience insect damage to increase their production of volatile molecules that attract natural enemies of herbivorous insects. In response to plant defences, herbivores increase their production of enzymes that detoxify allelochemicals, including cytochrome P450s (refs 15, 16). But herbivores are potentially vulnerable to toxic allelochemicals in the duration between ingesting toxins and induction of detoxification systems. Here we show that the corn earworm Helicoverpa zea uses jasmonate and salicylate to activate four of its cytochrome P450 genes that are associated with detoxification either before or concomitantly with the biosynthesis of allelochemicals. This ability to 'eavesdrop' on plant defence signals protects H. zea against toxins produced by host plants.     

永丰县种子植物统计分析及其属的分布区类型

对永丰县种子植物进行了统计分析,并研究了其属的分布类型及区系特征.结果表明:该县种子植物种类丰富,共有1340种,隶属于202科、721属;且优势科、属明显.属的分布区类型具有明显的热带性质和温带成分,在植物区系分区上处于从亚热带向温带过渡范围内;且起源古老,成分复杂.     

牛瘤胃中琥珀酸产生菌的分离鉴定研究

通过添加地克球利进行富集培养,结合溴甲酚绿中性平板从牛瘤胃中初步筛选得300株产酸菌,TLC法点样分离出31株菌有不同程度的琥珀酸生产能力,进一步地HPLC法定性定量,复筛得8株发酵性状较优菌株,其中最有潜力的一株菌NO.4发酵琥珀酸累积产量达16.8 g/L。针对菌株的细胞及菌落形态研究表明,菌落为圆形凸起,表面光滑,不透明或半透明,呈浅兰色或乳白色,边缘整齐,菌体呈球状,细胞大多数单个或成双甚至成串出现,菌体兼性厌氧,呈革兰氏阳性,无内生芽孢,有荚膜,可运动。对菌株的进一步生理生化和16s-rRNA分析确认为Leuconostoc mesenteroides,最终将菌株NO.4命名为L.mesenteroides JST。     

Honeybee colonies achieve fitness through dancing

The honeybee dance language, in which foragers perform dances containing information about the distance and direction to food sources, is the quintessential example of symbolic communication in non-primates. The dance language has been the subject of controversy, and of extensive research into the mechanisms of acquiring, decoding and evaluating the information in the dance. The dance language has been hypothesized, but not shown, to increase colony food collection. Here we show that colonies with disoriented dances (lacking direction information) recruit less effectively to syrup feeders than do colonies with oriented dances. For colonies foraging at natural sources, the direction information sometimes increases food collected, but at other times it makes no difference. The food-location information in the dance is presumably important when food sources are hard to find, variable in richness and ephemeral. Recruitment based simply on arousal of foragers and communication of floral odour, as occurs in honeybees, bumble bees and some stingless bees, can be equally effective under other circumstances. Clarifying the condition-dependent payoffs of the dance language provides new insight into its function in honeybee ecology.     

一种求解TSP问题的改进蚂蚁群算法

通过用混合型蚂蚁群算法求解TSP问题的方法和步骤 ,并以att5 32 (美国 5 32个城市 )为例给出计算实验结果 ,说明混合型蚂蚁群算法改进了标准蚂蚁群算法的效率和计算结果的质量