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61.
This paper, which presents an annotated checklist of the ‘lower Nymphalidae’ (Libytheinae, Danainae, Satyrinae, Charaxinae), is the fourth in a series on the butterfly fauna of Mount Kilimanjaro. Four genera of lower Nymphalidae (Danaus, Amauris, Bicyclus, Charaxes), with a total of 11 included species, are known or believed to occur within the main forest zone, from c. 1800 to 2800 m. Of these, only three species of Charaxes (Charaxes berkeleyi, Charaxes ansorgei, Charaxes xiphares) may be restricted locally to this primary forest. The lower slopes fauna, below 1800 m, is considerably richer, with a total of 11 genera and 41 species listed (8 species of which extend into the forest zone). Possible additional species, dubious earlier records, problems with African subspecies of Danaus chrysippus, a need for more work on certain Satyrinae, and classification of the genus Charaxes are discussed. An identification key to the subfamilies of Nymphalidae, and the 19 genera of Libytheinae, Danainae, Satyrinae, Charaxinae that occur in Tanzania, together with a key to the adults of all the species of these four subfamilies considered to occur or have occurred on Kilimanjaro, with 206 colour images, are included as online Supplementary Information. 相似文献
62.
Treed Avalanche Forecasting: Mitigating Avalanche Danger Utilizing Bayesian Additive Regression Trees 下载免费PDF全文
Little Cottonwood Canyon Highway is a dead‐end, two‐lane road leading to Utah's Alta and Snowbird ski resorts. It is the only road access to these resorts and is heavily traveled during the ski season. Professional avalanche forecasters monitor this road throughout the ski season in order to make road closure decisions in the face of avalanche danger. Forecasters at the Utah Department of Transportation (UDOT) avalanche guard station at Alta have maintained an extensive daily winter database on explanatory variables relating to avalanche prediction. Whether or not an avalanche crosses the road is modeled in this paper via Bayesian additive tree methods. Utilizing daily winter data from 1995 to 2011, results show that using Bayesian tree analysis outperforms traditional statistical methods in terms of realized misclassification costs that take into consideration asymmetric losses arising from two types of error. Closing the road when an avalanche does not occur is an error harmful to resort owners, and not closing the road when one does may result in injury or death. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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A. Venerando L. Cesaro O. Marin A. Donella-Deana L. A. Pinna 《Cellular and molecular life sciences : CMLS》2014,71(12):2193-2196
The motif “SYDE”, incorporating the protein kinase CK2 consensus sequence (S-x-x-E) has been found to be phosphorylated at both its serine and tyrosine residues in several proteins. Of special interest is the case of cystic fibrosis Transmembrane-conductance Regulator (CFTR), where this motif is close to the residue (F508), whose deletion is the by far commonest cause of cystic fibrosis. Intriguingly, however, CFTR S511 cannot be phosphorylated by CK2 to any appreciable extent. Using a number of peptide substrates encompassing the CFTR “SYDE” site we have recently shown that: (1) failure of CK2 to phosphorylate the S511YDE motif is due to the presence of Y512; (2) CK2 readily phosphorylates S511 if Y512 is replaced by a phospho-tyrosine; (3) the Src family protein tyrosine kinase Lyn phosphorylates Y512 in a manner that is enhanced by the deletion of F508. These data, in conjunction with the recent observation that by inhibiting CK2 the degradation of F508delCFTR is reduced, lead us to hypothesize that the hierarchical phosphorylation of the motif SYDE by the concerted action of protein tyrosine kinases and CK2 is one of the mechanisms that cooperate to the premature degradation of F508delCFTR. 相似文献
64.
Wilson J. E. M. Costa Axel M. Katz José Leonardo O. Mattos Pedro F. Amorim Beatrizz O. Mesquita Paulo J. Vilardo 《Journal of Natural History》2019,53(47-48):2905-2928
ABSTRACT This study is primarily directed to the most poorly known species of the genus Trichomycterus, comprising five nominal species (T. florensis, T. immaculatus, T. nigricans, T. paquequerensis and T. santaeritae) endemic to south-eastern Brazil. One of them, T. nigricans, is the type species of the genus, involved in taxonomic problems for over 150 years. A detailed historical review, accompanied by examination of type specimens and recent collections, revealed that the correct type locality of T. nigricans is in the vicinity of Rio de Janeiro, not Santa Catarina as commonly appears in the literature; specimens previously misidentified as T. nigricans from Santa Catarina belong to a possibly undescribed species of the genus Cambeva; T. paquequerensis is a synonym of T. immaculatus, and T. florensis is a synonym of T. santaeritae; and the hypothesis that T. santaeritae is closely related to the Amazon Sarcoglanidinae is refuted. The three valid species are redescribed. These species are members of a clade also including T. caipora that is highly supported by molecular data, diagnosed by a pronounced posterior maxillary process and caudal fin emarginate at least in larger specimens. A subclade comprising T. caipora, T. nigricans and T. santaeritae is diagnosed by a long maxilla and a bifid anterior extremity of hypobranchial 3. 相似文献
65.
Water mites Limnochares aquatica (L., 1758) during maintenance in the laboratory for a long period of time in constant conditions periodically produced certain whitish flocculent material consisting of long rigid unbranched tube-like threads 1.3 ± 0.3 µm in diameter crossing freely. These threads were studied using light-optical as well as transmission electron microscopical and scanning electron microscopical methods. Microbiological staining was also applied to the threads to exclude their bacterial or fungal origin. The thread wall is built of fine fibrils arranged at different angles to the long axis of threads that is reflected in a certain stratification of the wall. Threads are mostly hollow or may contain electron-dense homogeneous material. No cell components are present in the thread composition. Numerous dermal glands with their small slit-like orifice scattered throughout the mite body surface are thought to produce these threads. Most probably the thread formation is a reaction of mites to stress under laboratory conditions, and this is expected to be a type of defensive reaction. 相似文献
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Systemic Practice and Action Research - This paper explores the usefulness of rich pictures as a method in Systemic Lean Intervention (SLI) process. It combines Lean and Systems Thinking analytical... 相似文献
69.
The universal acceptance of atomism in physics and chemistry in the early 20th century went along with an altered view on the epistemic status of microphysical conjectures. Contrary to the prevalent understanding during the 19th century, on the new view unobservable objects could be ‘discovered’. It is argued in the present paper that this shift can be connected to the implicit integration of elements of meta-empirical theory assessment into the concept of theory confirmation. 相似文献
70.