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61.
At the northern periphery of the Dja Biosphere Reserve (southeastern Cameroon) we recorded a new use of a tool-set by Pan troglodytes troglodytes to prey on Macrotermes muelleri, M. renouxi, M. lilljeborgi, and M. nobilis. We recovered 79 puncturing sticks and 47 fishing probes at 17 termite nests between 2002 and 2005. The mean length of the puncturing sticks (n = 77) and fishing probes (n = 45) was 52 cm and 56 cm, respectively, and the mean diameter was 9 mm and 4.5 mm, respectively. Sixty-eight percent of 138 chimpanzee fecal samples contained major soldiers of four Macrotermes species. The chimpanzees in southeastern Cameroon appeared to be selective in their choice of plant material to make their tools. The tools found at our study site resemble those from other sites in this region. However, in southeastern Cameroon only one tool-set type was found, whereas two tool-set types have been reported in Congo. Our study suggests that, along with the different vegetation types and the availability of plant material around termite nests, the nest and gallery structure and foraging behavior of the different Macrotermes spp. at all Central African sites must be investigated before we can attribute differences in tool-use behavior to culture.  相似文献   
62.
Current knowledge of the evolutionary relationships amongst the wolf spiders (Araneae: Lycosidae) is based on assessment of morphological similarity or phylogenetic analysis of a small number of taxa. In order to enhance the current understanding of lycosid relationships, phylogenies of 70 lycosid species were reconstructed by parsimony and Bayesian methods using three molecular markers; the mitochondrial genes 12S rRNA, NADH1, and the nuclear gene 28S rRNA. The resultant trees from the mitochondrial markers were used to assess the current taxonomic status of the Lycosidae and to assess the evolutionary history of sheet-web construction in the group. The results suggest that a number of genera are not monophyletic, including Lycosa, Arctosa, Alopecosa, and Artoria. At the subfamilial level, the status of Pardosinae needs to be re-assessed, and the position of a number of genera within their respective subfamilies is in doubt (e.g., Hippasa and Arctosa in Lycosinae and Xerolycosa, Aulonia and Hygrolycosa in Venoniinae). In addition, a major clade of strictly Australasian taxa may require the creation of a new subfamily. The analysis of sheet-web building in Lycosidae revealed that the interpretation of this trait as an ancestral state relies on two factors: (1) an asymmetrical model favoring the loss of sheet-webs and (2) that the suspended silken tube of Pirata is directly descended from sheet-web building. Paralogous copies of the nuclear 28S rRNA gene were sequenced, confounding the interpretation of the phylogenetic analysis and suggesting that a cautionary approach should be taken to the further use of this gene for lycosid phylogenetic analysis.  相似文献   
63.
The Semantic Web for the Life Sciences (SWLS), when realized, will dramatically improve our ability to conduct bioinformatics analyses using the vast and growing stores of web-accessible resources. This ability will be achieved through the widespread acceptance and application of standards for naming, representing, describing and accessing biological information. The W3C-led Semantic Web initiative has established most, if not all, of the standards and technologies needed to achieve a unified, global SWLS. Unfortunately, the bioinformatics community has, thus far, appeared reluctant to fully adopt them. Rather, we are seeing what could be described as 'semantic creep'-timid, piecemeal and ad hoc adoption of parts of standards by groups that should be stridently taking a leadership role for the community. We suggest that, at this point, the primary hindrances to the creation of the SWLS may be social rather than technological in nature, and that, like the original Web, the establishment of the SWLS will depend primarily on the will and participation of its consumers.  相似文献   
64.
Circular dichroism (CD) is a spectroscopic technique commonly used to investigate the structure of proteins. Major secondary structure types, alpha‐helices and beta‐strands, produce distinctive CD spectra. Thus, by comparing the CD spectrum of a protein of interest to a reference set consisting of CD spectra of proteins of known structure, predictive methods can estimate the secondary structure of the protein. Currently available methods, including K2D2, use such experimental CD reference sets, which are very small in size when compared to the number of tertiary structures available in the Protein Data Bank (PDB). Conversely, given a PDB structure, it is possible to predict a theoretical CD spectrum from it. The methodological framework for this calculation was established long ago but only recently a convenient implementation called DichroCalc has been developed. In this study, we set to determine whether theoretically derived spectra could be used as reference set for accurate CD based predictions of secondary structure. We used DichroCalc to calculate the theoretical CD spectra of a nonredundant set of structures representing most proteins in the PDB, and applied a straightforward approach for predicting protein secondary structure content using these theoretical CD spectra as reference set. We show that this method improves the predictions, particularly for the wavelength interval between 200 and 240 nm and for beta‐strand content. We have implemented this method, called K2D3, in a publicly accessible web server at http://www. ogic.ca/projects/k2d3 . Proteins 2012. © 2011 Wiley Periodicals, Inc.  相似文献   
65.
Sun Y  Zeng F  Zhang W  Qiao J 《Gene》2012,499(2):288-296
Antibiotic glycosyltransferases (AGts) attach unusual deoxy-sugars to aglycons so antibiotics can exert function. It has been reported that polyene macrolide (PEM) AGts have different evolutionary origin when compared with other polyketide AGts, and our previous analysis have suggested that they could be results of horizontal gene transfer (HGT) from eukaryotes. In this paper, we compared the structures of PEM AGts with structures of eukaryotes and other AGts, and then built models of the representative PEM AGts and GT-1 glycosyltransferases. We also constructed the Neighbor-Joining (NJ) trees based on the normalized Root Mean Square (RMS) distance, the Bayesian tree guided by structural alignments, and carried out analysis on several key conserved residues in PEM AGts. The NJ tree showed a close relationship between PEM AGts and eukaryotic glycosyltransferases, and Bayesian tree further supported their affinity with UDP-glucuronosyltransferases (UGTs). Analysis on key conserved residues showed that PEM AGts may have similar interaction mechanism such as in the formation of hydrogen bonds as eukaryotic glycosyltransferases. Using structure-based phylogenetic approaches, this study further supported that PEM AGts were the result of HGT between prokaryotes and eukaryotes.  相似文献   
66.
Xu K  Doak TG  Lipps HJ  Wang J  Swart EC  Chang WJ 《Gene》2012,498(1):75-80
Genome-wide methylation studies frequently lack adequate controls to estimate proportions of background reads in the resulting datasets. To generate appropriate control pools, we developed technique termed nMETR (non-methylated tag recovery) based on digestion of genomic DNA with methylation-sensitive restriction enzyme, ligation of adapter oligonucleotide and PCR amplification of non-methylated sites associated with genomic repetitive elements. The protocol takes only two working days to generate amplicons for deep sequencing. We applied nMETR for human DNA using BspFNI enzyme and retrotransposon Alu-specific primers. 454-sequencing enabled identification of 1113 nMETR tag sites, of them ~65% were parts of CpG islands. Representation of reads inversely correlated with methylation levels, thus confirming nMETR fidelity. We created software that eliminates background reads and enables to map and annotate individual tags on human genome. nMETR tags may serve as the controls for large-scale epigenetic studies and for identifying unmethylated transposable elements located close to genomic CpG islands.  相似文献   
67.
ABSTRACT

In this paper, we present an activity called ‘Annapurna Expedition’ through which students should apply basic concepts of genetics to solve a worldwide pandemic disease. Players take the role of scientists, involved in a research to find out which pathogen causes this pandemic and which could be the best way to solve it. Students have the opportunity to use BLAST software as a scientific bioinformatic tool to discover the main game’ enigmas. The activity uses game-based science learning methodology. This methodology incorporates multiple tools and resources, rely on learning by doing, guiding learners through a path of events and into a way of thinking. It provides students to take information from many sources and make decisions, to deduce a game’s obstacles, to understand complex systems and to collaborate with other classmates.

The activity has been developed for a range of audiences, including high school students and pre-service teachers. A case study has been carried out with a group of 80 primary pre-service teachers from the Universitat Rovira i Virgili (URV) in Tarragona (Spain) in order to verify whether this activity was well designed, engage students and it is satisfactorily implemented.  相似文献   
68.
Class Work with Fungi. H. A. DADE and JEAN GUNNELL. Pp. 64. London: Commonwealth Mycological Institute, Kew. 1969. 10s. Review by B. M. Jones

The Insects: Structure and Function. R. F. CHAPMAN. Pp. xiii + 819 + 509 figs. London: The English Universities Press Ltd., 1969. £4.25. Review by T. G. Onions

An Introduction to the Principles of Plant Physiology. WALTER STILES and E. C. COCKING. Pp. 633. London: Methuen &; Co., Ltd. Third edition, 1969. 168s. Review by B. M. Jones

Background Notes to the Study of Human Biology for Nurses. T. ROBERTS. Pp. 80. London: Edward Arnold. Semistiff Back, 10s. (50p.). Review by J. H. Elliott  相似文献   
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