华南主要作物和蔬果类现代花粉形态及农业考古研究价值

本文对华南地区主要的19科31种作物和蔬果类花粉进行了形态学研究,包括镜下观察、拍照和特征描述与对比。本研究涉及的花粉包括粮食作物4种,蔬菜类16种,水果类8种,油料和经济作物3种等。结果表明,不同作物的花粉在形态、大小、萌发器官和外壁纹饰等方面有明显的差别,同一科植物花粉的主要形态虽有相似之处,但根据某些细微结构特征,并通过统计学方法在一定程度上可以对相近的种类进行区别。本文对十字花科芸苔属4种蔬菜花粉(油菜、芥菜、菜心和小白菜)的扁率(赤道轴长/极轴长)以及外壁网眼长轴长度分别进行测量,发现外壁网眼长轴长度对于4种蔬菜的区分不明显,而扁率则分异显著,可为十字花科花粉种属判别提供依据。对重庆阿蓬江涪碛口遗址剖面中自明清时期以来的伴人植物十字花科花粉赤道轴长与外壁网眼长轴长度进行了测量,判别出文化层中的十字花科花粉可能为菜心类型。稻田中保存的水稻花粉直径约为34—38μm,结合水稻花粉的其它特征可以应用到全新世地层的水稻花粉鉴定。     

中国甘肃南部沟颈螺属一新种(柄眼目,艾纳螺总科)

描述了栖息于甘肃南部的陆生贝类艾纳螺科1新种,诺氏沟颈螺Holcauchen nordsiecki sp.nov..与各已知种相比,诺氏沟颈螺的体螺层和次体螺层最膨大;腔壁齿极弱;腭壁板齿阙如;腭壁凹陷极微弱;具上大下小2枚轴唇齿;在生殖系统中,鞭状器小;成荚器无盲囊;具纳精囊管分支盲管.诺氏沟颈螺,新种Holcauchen nordsiecki sp.nov.(图1～6)新种的鉴别特征:体螺层与次体螺层最膨大;腔壁齿极弱;无腭壁板齿;腭壁凹陷极微弱;轴唇齿2枚,上大下小.鞭状器小;成荚器无盲囊;纳精囊管具分支盲管.贝壳:螺层数6.25 ～ 6.88;壳高6.9 ～7.0 mm;壳径2.4～2.7 mm.正模,HBUMM06664-specimen 1,具软体部的成体;甘肃文县(33°05′N,104°21′E;海拔1 269m),2011-08-09;吴岷、徐沁、Prem B.Buhda采.副模,HBUMM06664-specimen 2～3,2头具软体部的成体;HBUMM06664-specimen 4,1枚成熟空壳;采集数据同正模.词源:新种种名源自德国贝类学家Hartmut Nordsieck的姓氏;名词.     

促溶剂对雷斯青霉发酵液流变特性的影响

目的:促溶剂通常用于甾体生物催化过程以提高底物溶解度,但在发酵液中添加促溶剂对菌体形态及发酵液特性的影响还少有报道。方法:利用旋转流变仪和顺磁分析仪分别对发酵液的流变特性及体积氧传递系数KLa进行监测。结果:无论是否添加促溶剂,发酵液都表现出非牛顿流体力学特性,但添加3%1,2丙二醇后同一时期发酵液稠度系数减小大约17%,而流动指数平均增加8%。结论:添加促溶剂使得发酵液表观黏度减小,体积氧传递系数增大,从而有利于甾体化合物的生物转化。     

Artificial selection on allometry: change in elevation but not slope

To what extent within-species (static) allometries constitute a constraint on evolution is the subject of a long-standing debate in evolutionary biology. A prerequisite for the constraint hypothesis is that static allometries are hard to change. Several studies have attempted to test this hypothesis with artificial-selection experiments, but their results remain inconclusive due to various methodological issues. Here, we present results from an experiment in which we selected independently on the slope and the elevation of the allometric relationship between caudal-fin size and body size in male guppies (Poecilia reticulata). After three episodes of selection, the allometric elevation (i.e. intercept at constant slope) had diverged markedly between the lines selected to increase or decrease it, and showed a realized heritability of 50%. In contrast, the allometric slope remained unaffected by selection. These results suggest that the allometric elevation is more evolvable than the allometric slope, this latter representing a potential constraint on adaptive trait evolution. To our knowledge, this study is the first artificial-selection experiment that directly tests the evolvability of static allometric slopes.     

Ecological radiation with limited morphological diversification in salamanders

A major goal of evolutionary biology is to explain morphological diversity among species. Many studies suggest that much morphological variation is explained by adaptation to different microhabitats. Here, we test whether morphology and microhabitat use are related in plethodontid salamanders, which contain the majority of salamander species, and have radiated into a striking diversity of microhabitats. We obtained microhabitat data for 189 species that also had both morphometric and phylogenetic data. We then tested for associations between morphology and microhabitat categories using phylogenetic comparative methods. Associations between morphology and ecology in plethodontids are largely confined to a single clade within one subfamily (Bolitoglossinae), whereas variation in morphology across other plethodontids is unrelated to microhabitat categories. These results demonstrate that ecological radiation and morphological evolution can be largely decoupled in a major clade. The results also offer a striking contrast to lizards, which typically show close relationships between morphology and microhabitat.     

Pefabloc – A sulfonyl fluoride serine protease inhibitor blocks induction of Diptericin in Drosophila l(2)mbn cells

Abstract Insects protect themselves against microbial infection by an efficient innate immune system that is activated by recognition of invariant microbial surface molecules. In the fruit fly Drosophila melanogaster the presence of bacteria is associated with expression of antimicrobial peptides in host immune‐competent tissues. Host receptors detect infection and relay the signal to mount the appropriate immune response. In Drosophila hemocyte‐like l(2)mbn cells pre‐infection treatment with Pefabloc, a commonly used serine protease inhibitor, induced two major effects: it blocked expression of the antibacterial peptide Diptericin in response to live Gram‐negative bacteria and bacterial surface molecules (crude lipopolysaccharide contaminated by peptidoglycans) and it induced morphological changes.     

Leaf morphology shift linked to climate change

Climate change is driving adaptive shifts within species, but research on plants has been focused on phenology. Leaf morphology has demonstrated links with climate and varies within species along climate gradients. We predicted that, given within-species variation along a climate gradient, a morphological shift should have occurred over time due to climate change. We tested this prediction, taking advantage of latitudinal and altitudinal variations within the Adelaide Geosyncline region, South Australia, historical herbarium specimens (n = 255) and field sampling (n = 274). Leaf width in the study taxon, Dodonaea viscosa subsp. angustissima, was negatively correlated with latitude regionally, and leaf area was negatively correlated with altitude locally. Analysis of herbarium specimens revealed a 2 mm decrease in leaf width (total range 1-9 mm) over 127 years across the region. The results are consistent with a morphological response to contemporary climate change. We conclude that leaf width is linked to maximum temperature regionally (latitude gradient) and leaf area to minimum temperature locally (altitude gradient). These data indicate a morphological shift consistent with a direct response to climate change and could inform provenance selection for restoration with further investigation of the genetic basis and adaptive significance of observed variation.     

The effect of chitooligosaccharide supplementation on intestinal morphology,selected microbial populations,volatile fatty acid concentrations and immune gene expression in the weaned pig

An experiment (complete randomised design) was conducted to investigate the effects of supplementing different molecular weights (MW) of chitooligosaccharide (COS) on intestinal morphology, selected microbial populations, volatile fatty acid (VFA) concentrations and the immune status of the weaned pig. A total of 28 piglets (24 days of age, 9.1 kg (± s.d. 0.80) live weight) were assigned to one of four dietary treatments for 8 days and then sacrificed. The treatments were (1) control diet (0 ppm COS), (2) control diet plus 5 to 10 kDa COS, (3) control diet plus 10 to 50 kDa COS and (4) control diet plus 50 to 100 kDa COS. The COS was included in dietary treatments at a rate of 250 mg/kg. Tissue samples were taken from the duodenum, jejunum and ileum for morphological measurements. Digesta samples were taken from the proximal colon to measure lactobacilli and Escherichia coli populations and digesta samples were taken from the caecum and proximal colon for VFA analysis. Gene expression levels for specific cytokines were investigated in colonic tissue of the pig. Supplementation of different MW of COS had no significant effect on pig performance during the post-weaning period (days 0 to 8; P > 0.05). The inclusion of COS at all MW in the diet significantly reduced faecal scores compared with the control treatment (P < 0.01). Pigs fed the 10 to 50 kDa COS had a higher villous height (P < 0.05) and villous height : crypt depth ratio (P < 0.05) in the duodenum and the jejunum compared with the control treatment. Pigs fed the 5 to 10 kDa COS had a lower lactobacilli population (P < 0.05) and E. coli population (P < 0.05) in the colon compared with the control group. Pigs offered the 5 to 10 kDa COS had significantly lower levels of acetic acid and valeric acid compared with the control group (P < 0.05). The inclusion of different MW of COS had no significant effect on the expression of the cytokines tumour necrosis factor-α, Interleukin (IL)-6, IL-8 and IL-10 in the gastro-intestinal tract of the weaned pig. The current results indicate that a lower MW of 5 to 10 kDa COS possessed an antibacterial activity, while the higher MW of 10 to 50 kDa was optimum for enhancing the intestinal structure.     

Unexpected role of lipocalin-type prostaglandin D synthase in brain: Regulation of glial cell migration and morphology

Lipocalin-type prostaglandin D synthase (L-PGDS) is one of the most abundant proteins in the cerebrospinal fluid. Nevertheless, its role in the central nervous system is far from clear. Here, we present evidence that L-PGDS induces glial cell migration and morphological changes in vitro and in vivo. We also identified myristoylated alanine-rich C-kinase substrate (MARCKS), heat shock proteins and actin as L-PGDS-binding proteins, demonstrating that MARCKS/Akt/Rho/Jnk pathways are involved in the L-PGDS actions in glia. We further show that the cell migration-promoting activity of L-PGDS is independent of PGD₂ production. The results suggest a novel non-enzymatic function of L-PGDS protein in brain inflammation, and may have an impact on glial cell biology and brain pathology related with reactive gliosis. L-PGDS is a potential drug target that can be exploited for therapeutic intervention of glia-driven neuroinflammation and related diseases.     

COLEOFASCICULUS GEN. NOV. (CYANOBACTERIA): MORPHOLOGICAL AND MOLECULAR CRITERIA FOR REVISION OF THE GENUS MICROCOLEUS GOMONT1

Species currently classified within the cyanobacterial genus Microcoleus were determined to fall into two distinct clades in a 16S rDNA phylogeny, one containing taxa within the Oscillatoriaceae, the other containing taxa within the Phormidiaceae. The two lineages were confirmed in an analysis of the 16S–23S internal transcribed spacer (ITS) region sequences and secondary structures. The type species for Microcoleus is M. vaginatus Gomont, and this taxon belongs in the Oscillatoriaceae. Consequently, Microcoleus taxa in the Phormidiaceae must be placed in separate genera, and we propose the new genus Coleofasciculus to contain marine taxa currently placed in Microcoleus. The type species for Coleofasciculus is the well‐studied and widespread marine mat‐forming species Microcoleus chthonoplastes (Mert.) Zanardini ex Gomont. Other characters separating the two families include type of cell division and thylakoid structure.