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Clear Division (clear + division)
Selected AbstractsLithosphere structure of Europe and Northern Atlantic from regional three-dimensional gravity modellingGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 1 2002T. P. Yegorova Summary Large-scale 3D gravity modelling using data averaged on a 1° grid has been performed for the whole European continent and part of the Northern Atlantic. The model consists of two regional layers of variable thickness,the sediments and the crystalline crust, bounded by reliable seismic horizons,the ,seismic' basement and the Moho surface. Inner heterogeneity of the model layers was taken into account in the form of lateral variation of average density depending on the type of geotectonic unit. Density parametrization of the layers was made using correlation functions between velocity and density. For sediments, sediment consolidation with depth was taken into account. Offshore a sea water layer was included in the model. As a result of the modelling, gravity effects of the whole model and its layers were calculated. Along with the gravity modelling an estimation of isostatic equilibrium state has been carried out for the whole model as well as for its separate units. Residual gravity anomalies, obtained by subtracting the gravity effect of the crust from the observed field, reach some hundred mGal (10,5 m s,2) in amplitude; they are mainly caused by density heterogeneities in the upper mantle. A mantle origin of the residual anomalies is substantiated by their correlation with the upper-mantle heterogeneities revealed by both seismological and geothermal studies. Regarding the character of the mantle gravity anomalies, type of isostatic compensation, crustal structure, age and supposed type of endogenic regime, a classification of main geotectonic units of the continent was made. As a result of the modelling a clear division of the continent into two large blocks,Precambrian East-European platform (EEP) and Variscan Western Europe,has been confirmed by their specific mantle gravity anomalies (0 ÷ 50 × 10,5 m s,2 and ,100 ÷,150 × 10,5 m s,2 correspondingly). This division coincides with the Tornquist,Teisseyre Zone (TTZ), marked by a gradient zone of mantle anomalies. In the central part of the EEP (over the Russian plate) an extensive positive mantle anomaly, probably indicating a core of ancient consolidation of the EEP, has been distinguished. To the west and to the east of this anomaly positive mantle anomalies occur, which coincide with a deep suture zone (TTZ) and an orogenic belt (the Urals). Positive mantle anomalies of the Alps, the Adriatic plate and the Calabrian Arc, correlating well with both high-velocity domains in the upper mantle and reduced temperatures at the subcrustal layer, are caused by thickened lithosphere below these structures. Negative mantle anomalies, revealed in the Western Mediterranean Basin and in the Pannonian Basin, are the result of thermal expansion of the asthenosphere shallowing to near-Moho depths below these basins. [source] Some types of vertebral pathologies in the Argar Culture (Bronze Age, SE Spain)INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 1 2010S. A. Jiménez-Brobeil Abstract A collection of 1825 vertebrae belonging to 105 individuals from several Argaric Culture sites (Bronze Age, SE of Spain) were studied. Several pathologies that could provide information about activity patterns were analysed, including spondylolysis, compression fractures and Schmorl's nodes. Spondylolysis appears exclusively in men. Compression fractures seem to be more related to age (osteoporosis) and are more frequent in women, but without statistical significance. Schmorl's nodes affect a large number of the individuals studied, with a slight predominance in men; there are no differences by age. The results obtained were compared with the available archaeological and anthropological information, which shows a clear division of activities by sex in the Argaric population. The validity of studying these pathologies as activity patterns is discussed. Copyright © 2008 John Wiley & Sons, Ltd. [source] Atypical presentations of pityriasis rosea: case presentationsJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 1 2005A Chuh ABSTRACT Atypical cases of pityriasis rosea (PR) are fairly common and less readily recognized than typical eruptions. We present four patients for whom we believe atypical PR is the most likely diagnosis. A 33-year-old man had purpuric lesions bilaterally on the legs with classical rash on the trunk. A 28-year-old woman had intensely pruritic and urticarial lesions. A 10-year-old girl had hundreds of small papular lesions 1,3 mm in size. A pregnant woman aged 26 had oral haemorrhagic ulcers with classical PR eruption on her trunk. The oral ulcers erupted and remitted at the same time as the generalized eruption. We reviewed the literature and proposed a classification based on rash morphology, rash size, rash distribution, number of lesions, site of lesions, severity of symptoms and course of the eruption. We believe that it is difficult to make a clear division to define typical and atypical PR, and that it is important not to ascribe any unusual or atypical skin eruption with PR unless other dermatoses have been excluded. [source] Evolutionary history of the ancient cutinase family in five filamentous Ascomycetes reveals differential gene duplications and losses and in Magnaporthe grisea shows evidence of sub- and neo-functionalizationNEW PHYTOLOGIST, Issue 3 2008Pari Skamnioti Summary ,,The cuticle is the first barrier for fungi that parasitize plants systematically or opportunistically. Here, the evolutionary history is reported of the multimembered cutinase families of the plant pathogenic Ascomycetes Magnaporthe grisea, Fusarium graminearum and Botrytis cinerea and the saprotrophic Ascomycetes Aspergillus nidulans and Neurospora crassa. ,,Molecular taxonomy of all fungal cutinases demonstrates a clear division into two ancient subfamilies. No evidence was found for lateral gene transfer from prokaryotes. The cutinases in the five Ascomycetes show significant copy number variation, they form six clades and their extreme sequence diversity is highlighted by the lack of consensus intron. The average ratio of gene duplication to loss is 2 : 3, with the exception of M. grisea and N. crassa, which exhibit extreme family expansion and contraction, respectively. ,,Detailed transcript profiling in vivo, categorizes the M. grisea cutinases into four regulatory patterns. Symmetric or asymmetric expression profiles of phylogenetically related cutinase genes suggest subfunctionalization and neofunctionalization, respectively. ,,The cutinase family-size per fungal species is discussed in relation to genome characteristics and lifestyle. The ancestry of the cutinase gene family, together with the expression divergence of its individual members provides a first insight into the drivers for niche differentiation in fungi. [source] Genetic relationships of sesame germplasm collection as revealed by inter-simple sequence repeatsPLANT BREEDING, Issue 3 2002D. H. Kim Abstract Inter-simple sequence repeats (ISSR) polymorphism was used to determine genetic relationships among 75 Sesamum indicum L. accessions of Korean and exotic sesame. Fourteen reliable ISSR primers were selected for the assessment of genetic diversity, yielding 79 amplification products. Of these polymerase chain reaction products, 33% revealed polymorphism among the 75 accessions. Genetic distances ranged from 0 to 0.255, with a mean genetic distance of 0.0687. The 75 accessions were divided into seven groups on the basis of unweighted pair-group method with arithmetic averages (UPGMA) cluster analysis. The largest group consisted of 25 Korean cultivars, eight Korean breeding lines and 17 world-wide accessions. The other groups included 25 accessions, several of which contained useful traits. The dendrogram did not indicate any clear division among sesame accessions based on their geographical origin. However, all Korean sesame cultivars except ,Namsankkae' were clustered in the same group, indicating a narrow gene pool. Some of the Korean breeding lines were spread along the dendrogram, showing enlargement of genetic diversity. The genetic diversity data uncovered in this study can be used in future breeding programmes. [source] A quantitative analysis of the Eutherian orbit: correlations with masticatory apparatusBIOLOGICAL REVIEWS, Issue 1 2008Philip G. Cox Abstract The mammalian orbit, or eye-socket, is a highly plastic region of the skull. It comprises between seven and nine bones, all of which vary widely in their contribution to this region among the different mammalian orders and families. It is hypothesised that the structure of the mammalian orbit is principally influenced by the forces generated by the jaw-closing musculature. In order to quantify the orbit, fourteen linear, angular and area measurements were taken from 84 species of placental mammals using a Microscribe-3D digitiser. The results were then analysed using principal components analysis. The results of the multivariate analysis on untransformed data showed a clear division of the mammalian taxa into temporalis-dominant forms and masseter-dominant forms. This correlation between orbital structure and masticatory musculature was reinforced by results from the size-corrected data, which showed a separation of the taxa into the three specialised feeding types proposed by Turnbull (1970): i.e. ,carnivore-shear', ,ungulate-grinding' and ,rodent-gnawing'. Moreover, within the rodents there was a clear distinction between species in which the masseter is highly developed and those in which the temporalis has more prominence. These results were reinforced by analysis of variance which showed significant differences in the relative orbital areas of certain bones between temporalis-dominant and masseter-dominant taxa. Subsequent cluster analysis suggested that most of the variables could be grouped into three assemblages: those associated with the length of the rostrum; those associated with the width of the skull; and those associated with the relative size of the orbit and the shape of the face. However, the relative area of the palatine bone showed weak correlations with the other variables and did not fit into any group. Overall the relative area of the palatine was most closely correlated with feeding type, and this measure that appeared to be most strongly associated with the arrangement of the masticatory musculature. These results give a strong indication that, although orbital structure is in part determined by the relative size and orientation of the orbits, the forces generated by the muscles of mastication also have a large effect. [source] In vitro studies of steroid hormones in neurofibromatosis 1 tumors and schwann cellsMOLECULAR CARCINOGENESIS, Issue 7 2007Lauren Fishbein Abstract The most common NF1 feature is the benign neurofibroma, which consists predominantly of Schwann cells. Dermal neurofibromas usually arise during puberty and increase in number throughout adulthood. Plexiform neurofibromas, associated with larger nerves, are often congenital and can be life threatening. Malignant peripheral nerve sheath tumors (MPNST) in NF1 are believed to arise from plexiforms in 5%,10% of patients. There are reports of increased potential for malignant transformation of plexiform tumors and increase in dermal neurofibromas, during pregnancy. These observations suggest that steroid hormones influence neurofibroma growth, and our work is the first to examine steroid hormone receptor expression and ligand-mediated cell growth and survival in normal human Schwann cells and neurofibroma-derived Schwann cell cultures. Immunohistochemistry and real-time PCR showed that estrogen receptors (ERs), progesterone receptor (PR), and androgen receptor are differentially expressed in primary neurofibromas and in NF1 tumor-derived Schwann cell cultures compared to normal Schwann cells. However, there is substantial heterogeneity, with no clear divisions based on tumor type or gender. The in vitro effects of steroid hormone receptor ligands on proliferation and apoptosis of early passage NF1 tumor-derived Schwann cell cultures were compared to normal Schwann cell cultures. Some statistically significant changes in proliferation and apoptosis were found, also showing heterogeneity across groups and ligands. Overall, the changes are consistent with increased cell accumulation. Our data suggest that steroid hormones can directly influence neurofibroma initiation or progression by acting through their cognate receptor, but that these effects may only apply to a subset of tumors, in either gender. © 2007 Wiley-Liss, Inc. [source] Do larvae evolve the same way as adults in Tingidae (Insecta: Heteroptera)?CLADISTICS, Issue 2 2004Eric Guilbert A recent cladistic analysis showed that adult traits of Tingidae, which exhibit a great variety of shapes, evolved homoplastically from simple to complex (Guilbert, 2001). These complex traits, often exaggerated, were hypothesized to be adaptive. However, this study, as well as another by Lis (1999), both based on adult morphology, contradict the traditional classification of Tingidae. A new analysis is performed here, that includes larval characters, which, like those of adults, have a great variety of shapes. The results corroborate the traditional classification of the Tingidae. No clear divisions among Tinginae are drawn from the analysis, but an evolutionary pattern of shapes among Tingidae emerges from this study. There is a global tendency for larval traits to evolve convergently from simple to complex, as suggested for adults. The pattern seen in adult and larval traits is independent, but consistent. These traits can be used in the same anti-predation context, but with different roles. [source] | ||||||||||||||||