Floral evolution in the monocot family Nartheciaceae (Dioscoreales): evidence from anatomy and development in Metanarthecium luteo‐viride Maxim.

The placement of Nartheciaceae within Dioscoreales is an unexpected result of molecular phylogenetics. Nartheciaceae generally differs from the rest of Dioscoreales in having less specialized flowers. Studies of this family are important to elucidate the evolutionary history of the order. Using scanning electron microscopy and light microscopy, we describe the details of the flower structure, initiation, and development in Metanarthecium, which is unique amongst Nartheciaceae in possessing both an almost superior ovary and septal nectaries. This is the first member of Dioscoreales for which all stages of organogenesis have been studied. Within Nartheciaceae, the presence/absence of septal nectaries and the position of the ovary are labile. The presence of post‐genital fusion in the gynoecium correlates with the presence of septal nectaries. Septal nectary morphology is complicated in Metanarthecium, which raises the question of whether its floral structure (including superior ovary) is plesiomorphic within Dioscoreales. The septal nectaries of Metanarthecium show homoplastic similarity with those of Allium (Asparagales). The presence/absence of a compitum is probably variable at the infraspecific level in Metanarthecium as a result of alternative possibilities of post‐genital fusion between ventral carpel margins. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 1–18.     

Melanins in Physiological Conditions Protect Against Lipoperoxidation. A Study on Albino and Pigmented Xenopus

The susceptibility to lipoperoxidation in liver of albino and pigmented Xenopus laevis Daudin, has been studied. Albino Xenopus liver was richer in polyunsaturated fatty acids (PUFAs) than the pigmented one; moreover, it was also richer in mitochondrial superoxide dismutase (MnSOD) and in reduced glutathione (GSH). The thiobarbituric acid-reactive substances (TBARS) values were more abundant in the albino tissue compared to the pigmented tissue both during spontaneous and Fe⁺⁺ induced lipoperoxidation. Therefore, when isolated and purified melanin, in physiological quantities, was added to albino tissue, the TBARS values drastically decreased. Thus, melanin, in our experimental conditions, protects the albino tissue even more than SOD and GSH do. Melanin, in our opinion, acts as an antioxidant, because it is able to scavenge O₂^?.     

DNA-Protein Complex in Circular DNA from Phage ϕ29

THE DNA of the B. subtilis phage ?29 has been described as unpermuted linear duplex molecules¹ of molecular weight 11 × 10⁶, but the formation of circular molecules has also been indicated, suggesting the existence of cohesive ends^1,2.     

EST‐derived polymorphic microsatellites from cultivated strawberry (Fragaria×ananassa) are useful for diversity studies and varietal identification among Fragaria species

Microsatellite or simple sequence repeat markers derived from expressed sequence tags (ESTs) provide genetic markers within potentially functional genes, which could be very useful for breeding programs. To date, the development of microsatellite markers in the genus Fragaria has focused mainly on Fragaria vesca. However, most of the interests of breeding programs relate to specific characteristics of cultivated strawberry. Here, we describe a set of 10 EST‐derived microsatellites from Fragaria × ananassa. These markers showed high levels of polymorphism within strawberry cultivars and among different Fragaria species, indicating their potential for genetic studies not only on strawberry but also in other species within the genus.     

人工林碳汇潜力新概念及应用

定量确定森林碳汇潜力有助于科学地评估森林对碳汇的潜在贡献及制定实现这种潜力所需要的经营管理措施。目前,国内外有关森林碳汇潜力缺乏统一的概念及计量方法。在综述国内外有关固碳潜力概念的基础上,引入时间动态构架和可持续性的概念,提出了针对人工林的固碳潜力概念并利用FORECAST模型以杉木人工林为例阐明此概念的实际意义与应用。     

Vertical transmission in feather mites: insights into its adaptive value

1. The consequences of symbiont transmission strategies are better understood than their adaptive causes. 2. Feather mites are permanent ectosymbionts of birds assumed to be transmitted mainly vertically from parents to offspring. The transmission of Proctophyllodes doleophyes Gaud (Astigmata, Proctophyllodidae) was studied in two European populations of pied flycatchers, Ficedula hypoleuca Pallas (Passeriformes, Muscicapidae). 3. The vertical transmission of this mite species is demonstrated here with an acaricide experiment. This study also compared (for two distant populations during 4 years) patterns in reductions in mite intensity in adult birds, from egg incubation to chick‐rearing periods, with the predictions of three hypotheses on how host survival prospects and mite intraspecific competition might drive feather mites' transmission strategy. 4. The results are in agreement with previous studies and show that feather mites transmit massively from parents to chicks. 5. The magnitude of the transmission was closer to that predicted by the hypothesis based on intraspecific competition, while a bet‐hedging strategy is also partially supported.     

False fairy wasps in Early Cretaceous amber from Spain (Hymenoptera: Mymarommatoidea)

Abstract: The fauna of false fairy wasps (Proctotrupomorpha: Bipetiolarida: Mymarommatoidea) occurring in Early Cretaceous (Albian) amber from north and north‐eastern Spain (Moraza, San Just, and El Soplao outcrops) is described. In total, 12 specimens have been recovered and four species recognized, all new: Alavaromma orchamum gen. nov. and sp. nov. (Alavarommatidae fam. nov.), Archaeromma hispanicum sp. nov. (Mymarommatidae), Galloromma alavaensis sp. nov., and G. turolensis sp. nov. (Gallorommatidae). The study indicates the necessity of revision and maybe fusion of both superfamilies, Mymarommatoidea and Serphitoidea, as the boundaries between them are less and less defined. However, major classificatory rearrangements must await the completion of the cladistic studies presently underway.     

Generic recircumscriptions of Oncidiinae (Orchidaceae: Cymbidieae) based on maximum likelihood analysis of combined DNA datasets

Phylogenetic relationships within the orchid subtribe Oncidiinae sensu Chase were inferred using maximum likelihood analyses of single and multilocus DNA sequence data sets. Analyses included both nuclear ribosomal internal transcribed spacer DNA and plastid regions (matK exon, trnH‐psbA intergenic spacer and two portions of ycf1 exon) for 736 individuals representing approximately 590 species plus seven outgroup taxa. Based on the well resolved and highly supported results, we recognize 61 genera in Oncidiinae. Mimicry of oil‐secreting Malpighiaceae and other floral syndromes evolved in parallel across the subtribe, and many clades exhibit extensive variation in pollination‐related traits. Because previous classifications heavily emphasized these floral features, many genera recognized were not monophyletic. Our classification based on monophyly will facilitate focused monographs and clarifies the evolution of morphological and biochemical traits of interest within this highly diverse subtribe. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 168 , 117–146.     

''Ciliated'' Tumour Cells In Ascitic Fluid From Two Cases of Cystadenocarcinoma of the Ovary

We report two cases of primary carcinoma of the ovary in which 'ciliated' adenocarcinoma cells were found in the ascitic fluid. Transmission electron microscopy revealed that these were not true cilia but rather a prolific growth of abnormal microvilli. The cytological findings were compared with the histological appearances of the primary tumour. No ciliated cells were seen in the primary tumour, suggesting that the formation of the microvilli represented an independent proliferation of the cells in the fluid. Special staining reactions for mucin, alkaline phosphatase and epithelial membrane antigen were identical in the primary tumour and the cells in the ascitic fluid.