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821.
Zafar A. Handoo Juan E. Palomares‐Rius Carolina Cantalapiedra‐Navarrete Gracia Liébanas Sergei A. Subbotin Pablo Castillo 《Zoological Journal of the Linnean Society》2014,172(2):231-264
Stunt nematodes are characterized by phenotypic plasticity, with overlapping morphology and morphometry leading to potential misidentification. Consequently, the application of integrative taxonomic approaches is useful to species delimitation based on a combination of different perspectives, e.g. morphology and DNA sequences. We conducted nematode surveys in cultivated and natural environments in Spain and the USA, from which we identified 18 known species of the family Telotylenchidae and two new taxa within the studied samples. These species were morphologically, morphometrically, and molecularly characterized. The results of light and scanning electron microscopic observations, and molecular and phylogenetic analysis also allowed two new species to be distinguished, described herein as B itylenchus hispaniensis sp. nov. and T ylenchorhynchus mediterraneus sp. nov. The phylogenetic analysis was carried out using molecular data from nuclear ribosomal DNA genes [D2–D3 expansion segments of the large ribosomal subunit (28S), internal transcribed spacer (ITS), and partial small ribosomal subunit (18S)]. We also provide here a test of alternative hypotheses that confirms the monophyly of both Tylenchorhynchus and Bitylenchus sensu Siddiqi's classification but does not support Fortuner & Luc's conceptual view of Tylenchorhynchus as a large genus. Ancestral state reconstructions of several diagnostic morphological characters using a maximum parsimony approach showed congruence in morphological and molecular evolution for stylet knob inclination and tail tip annulation. Our analysis emphasizes some of the problems related to the taxonomy and phylogeny of nematodes of Telotylenchinae. © 2014 The Linnean Society of London 相似文献
822.
In this study we describe a new kind of sperm gigantism in the stalk-eyed fly, Diasemopsis comoroensis (Diptera, Diopsidae). The sperm cells have a length of up to 1.7 mm and can be coiled into a compact ‘slinky’ spiral. Their ultrastructure involves a prominent electron dense central band, which runs the entire length of the sperm tail and in some regions constitutes its largest element in cross section. We propose that this organelle is either a giant centriole adjunct or a kind of accessory body derived from it, and that it takes part in coiling the sperm tail. To our knowledge, no comparable structure has been described before. 相似文献
823.
Mitchell J. B. and Mason A. R. 1978. Escape of the cercarial body of Gorgoderina vitelliloba from its anterior tail chamber. International Journal for Parasitology8: 193–198. Before the cercarial body of Gorgoderina vitelliloba can encyst in the body of its second intermediate host it must escape from the anterior tail chamber where it has been confined throughout the free living cercarial phase. Escape from the tail chamber is influenced by pH, enzymes, bile salts and by the physical nature of its environment. The cercarial body effects its escape after first becoming activated and then breaking its connection with the tail. 相似文献
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We investigated locomotor and postural behavior during terminal branch feeding in order to gain a better understanding of the motor capabilities of primates. We videotaped wild, juvenile bonnet macaques (Macaca radiata) in India as they fed on flower nectar in a simal tree (Bombax malabaricum). Kinematic analysis revealed that they select specific support surfaces and movements that, for their body design and postures, maximize lateral stability and minimize the chances of falling. These choices are made even though the distance and duration of travel to a selected target are frequently increased. Our discussion focuses on particular concepts of how primates contend with balance problems arboreally, potential reasons for changes in footfall patterns, and how the tail contributes to arboreal locomotion and posture. We concluded that balance problems due to the ratio of body size to branch size are usually avoided, at least among juvenile bonnet macaques, by placing the hands and feet on branches extending laterally from the central support branch and not on the central branch itself. The lateral branches permit a wide base of support, which increases lateral stability. Second, juvenile bonnet macaques have a striking ability to rapidly and repeatedly adapt their gait patterns to changing substrate design with minimal interruption to overall progression. Third, primate tails that are not morphologically specialized for prehension nevertheless have important prehensile and sensory functions in arboreal locomotion and posture. 相似文献
826.
Identification of Endogenously Phosphorylated KSP Sites in the High-Molecular-Weight Rat Neurofilament Protein 总被引:2,自引:0,他引:2
Eytan Elhanany Howard Jaffe William T. Link Douglas M. Sheeley Harold Gainer Harish C. Pant 《Journal of neurochemistry》1994,63(6):2324-2335
Abstract: The high-molecular-weight neurofilament protein (NF-H) is highly phosphorylated in vivo, with estimates as high as 16–51 mol of Pi /mol of protein. Most of the phosphorylation sites are thought to be located on Ser residues in multiple KSP repeats, in the carboxy-terminal tail region of the molecule. Because the extent and site-specific patterns of tail domain phosphorylation are believed to modulate neurofilament structure and function, it becomes essential to identify the endogenous sites of phosphorylation. In this study, we have used selective proteolytic cleavage procedures, Pi determinations, microsequencing, and mass-spectral analysis to determine the endogenously phosphorylated sites in the NF-H tail isolated from rat spinal cord. Twenty Ser residues in NF-H carboxy-terminal tail were analyzed; nine of these, all located in KSP repeats, were phosphorylated. No detectable phosphorylation could be identified in any of the 11 "non-KSP" Ser residues that were examined. KSPXKX, KSPXXX, and KSPXXK motifs were found to be phosphorylated. In addition, a 27-kDa KSP-rich domain, containing 43 virtually uninterrupted KSPXXX repeats, was isolated from the tail domain and found to contain between 30 and 35 mol of Pi /mol of protein. This domain appeared to be highly resistant to endoproteinase Glu-C digestion, although it contains a large number of glutamate residues. It could be proteolyzed, however, after dephosphorylation. This suggests that phosphorylation of the tail domain may contribute to neurofilament stability in vivo. A neuronal-derived protein kinase that specifically phosphorylates only KSPXKX motifs in neurofilaments has been reported. The presence of extensively phosphorylated KSPXXX repeats in NF-H in vivo suggests the existence of yet another, unidentified kinase(s) with specificity for KSPXXX motifs. 相似文献
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830.
William P. Brown Janelle P. Davidson Marion E. Zuefle 《Journal of applied animal welfare science : JAAWS》2013,16(1):2-18
Adoption records from 2 no kill shelters in New York State were examined to determine how age, sex, size, breed group, and coat color influenced the length of stay (LOS) of dogs at these shelters. Young puppies had the shortest length of stay; LOS among dogs increased linearly as age increased. Neither coat color nor sex influenced LOS. Considering only size classifications, medium-size dogs had the greatest LOS, and extra small dogs and puppies remained in shelters for the least amount of time. Considering only breed groupings, dogs in the guard group had the greatest LOS and those in the giant group had the shortest LOS. The lack of effect of coat color was not expected, nor was the shorter LOS among “fighting” breeds compared with other breed groups. Coat color and breed may have only local effects on LOS that do not generalize to all shelters, including traditional shelters. Understanding the traits of dogs in a specific shelter and the characteristics of these nonhuman animals desired by adopters are critical to improving the welfare of animals served by that shelter. 相似文献