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111.
The taxonomic position of Hormaphis similibetulae Qiao & Zhang, 2004 has been reexamined. The phylogenetic position of Hormaphis similibetulae was inferred by maximum parsimony, maximum likelihood and Bayesian analyses on the basis of partial nuclear elongation factor-1α and mitochondrial tRNA leucine/cytochrome oxidase II sequences. The results showed that this species fell into the clade of Hamamelistes species, occupying a basal position, and was clearly distinct from other Hormaphis species. A closer relationship between Hormaphis similibetulae and Hamamelistes species was also revealed by life cycle analysis. Therefore, we conclude that Hormaphis similibetulae should be transferred to the genus Hamamelistes as Hamamelistes similibetulae (Qiao & Zhang), comb. n. 相似文献
112.
《Journal of biological education》2012,46(3):113-117
Several developments in science education aim to improve pupils' ability to ‘think scientifically’. This paper argues for the explicit teaching of the ideas that pupils need to ‘think about’ to do this; ideas related to the design of investigations and the collection, presentation, analysis, and evaluation of the resulting evidence — ideas which are important both for pupils who continue to study or work with biology and for all pupils to become biologically literate. This paper considers some of the concepts of evidence which are particularly important to biology, and discusses how and why the ideas could be taught. 相似文献
113.
《Journal of biological education》2012,46(4):224-226
Argumentation in science is the process of coordinating theory and evidence to justify conclusions. This practice is at the heart of scientific journal writing and communication, but little is known regarding the argument quality of college science majors, the future scientists. Studies on written arguments at the college level have focused primarily on non-majors and upper-level students. To investigate and describe these skills throughout the biology curriculum, majors (n = 243) in four levels of undergraduate biology courses at a public university were assessed using a short, written argument instrument based on a hypothetical data set and scenario. Using Toulmin’s argumentation pattern to assess the instruments for argument aspects and quality, very few differences were found in the scores across course levels. Students were able to generate simple arguments consisting of claim, evidence and reasoning. The ability to provide scientific principles as reasoning to connect evidence and claims was positively correlated with course level. However, advanced argumentation skills, such as creating alternative explanations and rebuttals, were lacking across all course levels. These findings imply the need for explicit attention to argument construction throughout the undergraduate biology curriculum. 相似文献
114.
The ichnological record provides valuable information on the lifestyle, behaviour, and other palaeobiological and palaeoecological aspects of the biota. Here, we describe an interesting case of bioerosion trace fossils in bones of Buitreraptor gonzalezorum Makovicky, Apesteguía and Agnolín, 2005, a deinonychosaurian theropod from the fossiliferous locality of La Buitrera, Río Negro, Patagonia, Argentina. The trace fossils are morphologically diverse and preserved in a great percentage of the skeleton, including the jaw, vertebrae and limbs. Four main groups of trace fossils have been informally named as Parallel-Edge Furrows, Overlapped Grooves, Punctures and Lined. Parallel-Edge Furrows are in turn subdivided into four subgroups: isolated furrows, parallel pairs, opposed pairs and a combination of parallel and opposed pairs. The bioerosion trace fossils were probably generated by scavenging activities, and the semi-articulated preservation of the skeleton and the small size of each individual trace indicate small-sized tracemakers. Mammals are the main candidates although some traces may have been generated by crocodyliforms and insects such as dermestids and termites. This evidence provides additional information about palaeoenvironmental conditions, taphonomic processes, taxonomic diversity and ecological relationships that characterised this part of northern Patagonia at Early Cretaceous times. 相似文献
115.
116.
Tropospheric ozone (O3) has adverse effects on human heath and vegetation. Forecasting its daily maximum level and assessing the factors that influence its dynamics are of great importance to Hong Kong and similar metropolitans in the world. In this article, we simulate the daily maximum O3 level in Hong Kong by applying the multilayer perceptron (MLP) model trained with the automatic relevance determination (ARD) method in a Bayesian evidence framework. The proposed model is named the MLP-ARD. By using the ARD method, the O3 influential factors, which are the model's input variables, can be ranked according to their relative importance in regard to the model's output variable, that is, the daily maximum O3 level. The formation and transportation mechanism of O3 for two selected air-monitoring sites can be grossly explained by the ranking information. Compared with the MLP model trained by the Levenberg–Marquardt algorithm, the predictive performance of the MLP-ARD for the aforementioned air-monitoring sites is more reliable and accurate in both episode and non-episode periods. 相似文献
117.
The nucleotide sequence of a long polymorphic region located 365 bp upstream from the human insulin gene is reported. The region is composed of 139 repeating sequences whose consensus structure is related to ACAGGGGTGTGGGG. Expansion in the number of repeating sequences appears to have taken place through duplication and triplication of 112–141-bp regions. However, ancestral polymorphic regions containing additions or deletions of 50 bp or more were not detected in two previous generations. 相似文献
118.
Tanja Wilke Wilko H. Ahlrichs Olaf R. P. Bininda-Emonds 《Journal of Zoological Systematics and Evolutionary Research》2020,58(4):823-857
This study represents the first phylogenetic reconstruction of Synchaetidae (Rotifera, Monogononta) and combines one morphological and two molecular data sets to derive the most comprehensive database for this taxon to date. Overall, 19 species were examined both morphologically (light- and scanning electron microscopy of habitus and trophi) and genetically (COI and 18S rRNA genes), thereby delivering new morphological information as well as the first molecular data for several species. Our results strongly support the monophyly of each of the three genera within Synchaetidae, with Synchaeta being the sister taxon of Polyarthra and Ploesoma. Resolution within each genus, however, was more poorly supported, possibly because of high levels of missing data for the more poorly known species that were also not re-discovered and revised in the present study. Nevertheless, an evolutionary reconstruction based on the total evidence topology indicates that the common ancestor of Synchaetidae was a rotatorivorous and pelagic freshwater rotifer exhibiting slightly enlarged lamellar trophi that were adapted to an enhanced pumping function. These features together with several, additional key character transformations (e.g., hatching independently from benthic or periphytic habitats) probably account for the success of Synchaetidae in pelagic environments and their being one of the most widely distributed and abundant rotifer taxa. 相似文献
119.
The quality of clinical trials with Harpagophytum procumbens 总被引:2,自引:0,他引:2
OBJECTIVE: To examine systematically the quality of the clinical trials investigating the effectiveness of Harpagophytum products. METHODS: Literature searches and enquiries to experts identified 20 studies of treatment with various Harpagophytum products (powder, aqueous and ethanolic extracts) for exacerbations of chronic musculoskeletal pain. Eight were open uncontrolled observational studies, one comparing progress under treatment for pain in back, knee and hip pain. Two were open comparisons with conventional treatment, only one of which was randomised. Ten were double-blinded, randomised controlled comparisons, 8 with placebo and 2 with NSAID comparator treatments. Indices of the internal and external validities were examined by reference to a checklist to see how well the studies answered the questions: do Harpagophytum products work and do they work as well as more conventional comparator treatments? RESULTS: The uncontrolled trials, though providing useful preliminary estimates of the possible effect of treating various conditions, could not separate the effects of the Harpagophytum product from whatever placebo effect might have been exerted in the circumstances of the study. The 2 open comparisons were open to performance, detection and/or selection bias. Of the 8 randomised double blinded controlled comparisons with placebo, 6 were marred by lack of transparency, one could not provide definitive evidence from its pre-selected principal outcome measure, and one provided good quality evidence of a dose dependent superiority of effect over placebo, though this was with a product that is not generally available for clinical practice. One of the randomised controlled comparisons with comparator (Doloteffin versus rofecoxib) was intended only as a pilot and studied too few patients for definitive conclusions whereas the other did provide good evidence that the powder, Harpadol is not importantly less effective than the weak NSAID diacerhein. CONCLUSIONS: Evidence of effectiveness of Harpagophytum products is not transferrable from product to product. The results of some studies suggest some effectiveness for some products, but for none of the clinically available products is the quality of evidence totally satisfactory. It is better so far with products that contain at least 50 mg of harpagoside in the daily dosage than with products (which happen to be of ethanolic extraction) that contain less. 相似文献
120.
John A. Finarelli 《Journal of Mammalian Evolution》2008,15(4):231-259
A total evidence phylogenetic analysis was performed for 14 extant and 18 fossil caniform genera using a data matrix of 5.6 kbp
of concatenated sequence data from six independent loci and 80 morphological characters from the cranium and dentition. Maximum
parsimony analysis recovered a single most parsimonious cladogram (MPC). The topology of the extant taxa in the MPC agreed
with previous molecular phylogenies. Phylogenetic positions for fossil taxa indicate that several taxa previously described
as early members of extant families (e.g., Bathygale and Plesictis) are likely stem taxa at the base of the Arctoidea. Taxa in the “Paleomustelidae” were found to be paraphyletic, but a monophyletic
Oligobuninae was recovered within this set of taxa. This clade was closely related to the extant genera Gulo and Martes, therefore, nested within the extant radiation of the family Mustelidae. This analysis provides a resolution to several discrepancies
between phylogenies considering either fossil taxa or extant taxa separately, and provides a framework for incorporating fossil
and extant taxa into comprehensive combined evidence analyses. 相似文献