棉铃虫滞育与抗逆性研究进展

本文综述了棉铃虫滞育与抗逆性的研究进展 ,包括滞育的类型、滞育的诱导与解除 ,以及抗寒性、抗热性、抗旱性等。其中着重论述了棉铃虫的越冬滞育及其抗寒能力     

Ichnological evidence on the behaviour of mitrates: two trails associated with the Devonian mitrate Rhenocystis

The mitrates are controversial marine Palaeozoic fossils, assigned either to the chordates or to the echinoderms. This paper describes two trails associated with the mitrate Rhenocystis from the Lower Devonian Hunsrück Slate, Bundenbach, Germany. They indicate that, just before death, the animals were moving tail-first with the flat dorsal surface of the head upward. This behaviour is consistent with the chordate theory of mitrates, rather than with either of the two current echinoderm interpretations.     

双波4号诱虫灯在棉铃虫测报和防治上的应用效果

棉铃虫蛾在双波４号灯下的峰次明显,蛾峰与田间卵峰吻合度好,反映虫情实际;而黑光灯有的代次不出现蛾峰,有时出现蛾峰,却滞后于卵峰。在南方棉区发生的３～５代,经９５～９６年统计灯区百株累计卵量比无灯区平均下降７９．０８％,距灯１００ｍ范围内平均下降８８．２８％,１５０ｍ范围内平均下降７５．４５％。     

Tracing the evolution of the holothurian body plan through stem‐group fossils

The fossil echinoderm Palaeocucumaria, from the early Devonian Hunsrück Slate of southwestern Germany, has been studied using both traditional techniques and X‐ray microtomography, and its anatomy clarified. Phylogenetic analysis shows that it is a stem‐group holothurian with a combination of characters that help understand how the modern (crown‐group) holothurian body plan developed. Echinoids and holothurians have evolved along different paths, by differential growth of the larval‐ and rudment‐derived body regions. Palaeocucumaria shows that late stem‐group holothurians had a water vascular organization with a single external madreporite and calcified stone canal leading to the aboral end of the peripharyngeal coelom, and five primary radial water vessels that gave rise to tentacle‐like tube‐feet. This fossil data, in combination with a molecular phylogeny based on 18 s‐like rRNA gene sequence data, is used to order evolutionary steps in the making of the crown‐group holothurian body plan. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 670–681.     

Krüppel样因子在肌肉组织中的功能研究进展

Krüppel样因子(Krüppel-like factors, KLFs)是一类C-末端含有3个C₂H₂锌指结构的转录因子,N-末端为转录调控结构域,能够结合多种特异蛋白质,介导转录调控。目前在人体基因组中共发现18种KLFs,它们在多种类型人类细胞的分化、表型维持和生理功能调控中发挥重要作用。多个KLFs参与了对人和动物的心肌、平滑肌和骨骼肌的发育和功能的调控。在心肌中,KLF4、KLF10、KLF11和KLF15参与心肌肥大的负调控,KLF6参与调控心脏纤维化,KLF13调控胚胎时期的心肌发育。在血管平滑肌中,KLF4受促增殖或促分化因子调控,介导调控血管平滑肌表型转换;KLF5促进血管平滑肌增殖,KLF8和KLF15抑制血管平滑肌增殖。在骨骼肌中,KLF2、KLF3、KLF4、KLF10和KLF15调控骨骼肌发育,此外,KLF15是肌肉组织能量代谢的调节因子。本文综述了KLFs在心肌、平滑肌和骨骼肌中的功能研究进展,为进一步揭示KLFs在肌肉组织中的作用和肌肉相关疾病的分子机制提供参考。     

New arthropods from the Lower Devonian Hunsru¨ck Slate (Lower Emsian, Rhenish Massif, western Germany)

Four new genera and species of arthropod, Cambronatus brasseli Wingertshellicus backesi Eschenbachiellus wuttkensis and Magnoculus blindi , are described from the Hunsru¨ck Slate (Lower Emsian) of Germany. All four occur in the Wingertshell Member in the vicinity of Bundenbach. They preserve remarkable details of the ventral morphology, including the appendages, as a result of pyritization. In each case the body consists of just two tagmata, a cephalon and a large number of similar trunk somites. Both Cambronatus Wingertshellicus have fluke-like appendages making up a tail fan. The affinities of these arthropods lie with the Crustacea, apart from Magnoculus , which is an arachnomorph, but they do not fall within those clades with modern representatives. They show that morphologies other than those represented by trilobites and modern arthropod groups persisted long after the Cambrian, at least in muddy bottom marine settings.     

荒漠区不同微生境下齿肋赤藓对一次降雪的生理生化响应

耐旱苔藓广泛分布于干旱半干旱荒漠地区, 对荒漠生态系统稳定性与功能多样性具有重要作用。齿肋赤藓(Syntrichia caninervis)是古尔班通古特沙漠苔藓结皮层的优势物种, 生于不同的微环境中。古尔班通古特沙漠冬、春季降雪频繁, 并能形成稳定的积雪层。目前关于降雪与微生境对齿肋赤藓生理生化特征影响的研究极为缺乏。该研究探讨了初冬一次降雪前后活灌丛、死灌丛和裸露地3种微生境下齿肋赤藓相关生理生化特征。结果表明, 与降雪前相比, 降雪后各微生境下齿肋赤藓植株的含水量、荧光活性、可溶性糖含量、超氧化物歧化酶(SOD)和过氧化物酶(POD)活性均有明显提高, 但脯氨酸、可溶性蛋白和丙二醛(MDA)含量有不同程度的降低。微生境对齿肋赤藓的生理指标有不同程度的影响, 而且与降雪具有显著的交互作用(脯氨酸除外)。降雪前后, 活灌丛下的齿肋赤藓具有较高的含水量和光合活性, 以及较低的保护酶(POD和SOD) 活性, 裸露地则表现出完全相反的特点。表明前者面临的胁迫最小, 生理活性最大, 但抗性较弱; 而后者具有更大的抗胁迫能力, 但生理活性低。降雪后, 脯氨酸、MDA、POD及SOD均与植株含水量呈显著负相关, 而荧光活性、可溶性糖及可溶性蛋白含量与植株含水量为显著正相关, 表明降雪降低了齿肋赤藓的水分胁迫程度, 改善并促进了生理活性与光合作用, 而且初冬的低温也起到了促进作用。     

电子鼻技术在快速检测小麦矮腥黑穗病菌中的应用

由小麦矮腥黑穗病菌(TCK)引起的小麦矮腥黑穗病是我国重要的检疫性病害,为明确电子鼻技术在快速检测小麦矮腥黑穗病菌方面的可行性,利用电子鼻对含有TCK和小麦光腥黑穗病菌(TFL)不同冬孢子数(50g小麦种子中冬孢子数分别为0、100、101、102、103、104、105)的小麦进行了检测,采用主成分分析法(PCA)和线性判别法(LDA)进行数据分析。结果发现,这2种分析方法均可将不含TCK冬孢子的小麦和含TCK冬孢子的小麦区分开来,而且通过LDA分析,可将TCK冬孢子含量为100、101、102及103以上的处理区分开来。另外,通过PCA分析,可将TCK与TFL区分开来。此结果为电子鼻技术在快速检测小麦矮腥黑穗病菌中的应用奠定了基础。     

河北蔚县南柏山遗址晚更新世河套大角鹿角化石

大角鹿是我国北方中-晚更新世遗址中最常见动物化石之一,也是更新世期间我国北方动物群的代表性动物之一。除周口店地区之外,其他遗址出土的大角鹿化石都十分零碎,极少有完整的大角鹿鹿角发现。再加上对大角鹿不同年龄阶段鹿角的发育情况更是知之甚少,因此,以往仅凭鹿角形态所做的分类值得商榷。2018年,在河北省蔚县南柏山旧石器时代遗址发现1件几乎完整的大角鹿鹿角化石。鹿角很大,眉枝和主枝掌部都呈薄片状,掌部无指突;眉枝和主枝掌部的延展面基本一致,但不完全平行,主枝角干在基部有明显弯曲,但“S”形并不明显,总体特征与晚更新世河套大角鹿(Sinomegaceros ordosianus)的基本一致。该标本是迄今发现的最完整的河套大角鹿角化石。含该化石的地层成因尚不确定,初步的光释光测年结果是距今约11万年前,属于旧石器时代中期。     

A generalized Luria-Delbrück model

We develop extensions of the Luria-Delbrück model that explicitly consider non-exponential growth of normal cells and a birth-death process with mean exponential or Gompertz growth of mutants. Death of mutant cells can be important in clones arising during cancer progression. The use of a birth-death process for growth of mutant cells, as opposed to a pure birth process as in previous work on the Luria-Delbrück model, leads to a large increase in the extra Poisson variation in the size of the mutant cell populations, which needs to be addressed in statistical analyses. We also discuss connections with previous work on carcinogenesis models.