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Different Character (different + character)
Selected AbstractsCladistic coding of genomic mapsCLADISTICS, Issue 5 2002Cyril Gallut A new method of genomic maps analysis is described. The purpose of the method is to reconstruct phylogenetic relationships from the genomic organization of taxa. Our approach is based on gene order coding. This coding allows the description of genome topology without a prior hypothesis about evolutionary events and phylogenetic relationships. Different characters are used for each gene: (1) presence/absence, (2) orientation, and (3) relative position. The relative position of a particular gene inside the genome is the pair of genes surrounding it. The relative position character represents all the positions of a gene in the sampled genomes. It is coded as a multistate character. Our coding method has a priori variable cost implications on operators such as inversion, transposition, and gene loss/gain, which we discuss. The overall approach best fits the "duplication, random loss" evolutionary model. The coding method allows the reconstitution of a possible hypothetical common ancestor genome at each node of the tree. This reconstitution is based on the character states' optimization; it comes down to choosing, among all possible optimizations, the optimization compatible with a complete genome topology at each internal node. The multistate coding of gene relative position, which is an undeniable advantage of this method, permits this reconstitution. [source] Compositional effects accompanying near equilibrium vapour growth of solid solution crystals of the types IV-VI and II-VICRYSTAL RESEARCH AND TECHNOLOGY, Issue 7 2010A. Szczerbakow Abstract Near equilibrium evaporation-condensation in a sealed ampoule leads to almost full compositional reproduction of a solid solution if it consists of components having comparable vapour pressures; this can be qualitatively interpreted by domination of entropy increase. Nevertheless, even vestigial separation requires closer characteristics, since it may prove crucial , particularly for properties of semiconducting solid solutions. Maximum component separation allowed by a small temperature difference is described here in terms of thermodynamics and kinetics of solid-vapour and vapour-solid phase transitions. Theoretical models of the determining effects having different character are shortly described, and their applicability areas are determined. Experimental data collected for crystal growth of numerous semiconducting solid solutions of the II-VI and IV-VI type support the conclusion drawn from the models that the near equilibrium crystal growth from the vapour in a closed system ensures the highest degree of compositional uniformity. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] VISION AS REVISION: RANKE AND THE BEGINNING OF MODERN HISTORYHISTORY AND THEORY, Issue 4 2007J. D. BRAW ABSTRACT It is widely agreed that a new conception of history was developed in the early nineteenth century: the past came to be seen in a new light, as did the way of studying the past. This article discusses the nature of this collective revision, focusing on one of its first and most important manifestations: Ranke's 1824 Geschichten der romanischen und germanischen Völker. It argues that, in Ranke's case, the driving force of the revision was religious, and that, subsequently, an understanding of the nature of Ranke's religious attitude is vital to any interpretation of his historical revision. Being aesthetic-experiential rather than conceptual or "positive," this religious element is reflected throughout Ranke's enterprise, in source criticism and in historical representation no less than in the conception of cause and effect in the historical process. These three levels or aspects of the historical enterprise correspond to the experience of the past, and are connected by the essence of the experience: visual perception. The highly individual character of the enterprise, its foundation in sentiments and experiences of little persuasive force that only with difficulty can be brought into language at all, explains the paradoxical nature of the Rankean heritage. On the one hand, Ranke had a great and lasting impact; on the other hand, his approach was never re-utilized as a whole, only in its constituent parts,which, when not in the relationship Ranke had envisioned, took on a new and different character. This also suggests the difference between Ranke's revision and a new paradigm: whereas the latter is an exemplary solution providing binding regulations, the former is unrepeatable. [source] Zimbabwe's Drought Relief Programme in the 1990s: A Re-Assessment Using Nationwide Household Survey DataJOURNAL OF CONTINGENCIES AND CRISIS MANAGEMENT, Issue 3 2006Lauchlan T. Munro Zimbabwe's Drought Relief Programme was hailed in the 1980s and 1990s as an effective response to a food crisis in a poor country. International observers in particular credited the Programme with preventing famine and protecting livelihoods. Even before the current political turmoil and the ensuing politicisation of Drought Relief that have afflicted Zimbabwe since 2000, Zimbabwean authors were more sceptical about the effectiveness of Drought Relief. Both sides in the debate, however, failed to substantiate their arguments with national household survey data on who got what kind of assistance from Drought Relief, but rather relied on administrative data, qualitative interviews or sub-national surveys. Drawing its inspiration from WHO's minimum evaluation procedure, this article uses data from four nationwide household surveys in 1992,1993 and 1995,1996 and various definitions of poverty to ask whether Drought Relief provided poor people with relevant, timely and adequate assistance in the 1990s. The analysis suggests that Drought Relief was effective in supporting drought-affected smallholders during the 1990s. Drought Relief generally had a slight pro-poor bias. Unfortunately, Drought Relief since 2000 has a very different character. [source] Hydrogen bonds and local symmetry in the crystal structure of gibbsiteMAGNETIC RESONANCE IN CHEMISTRY, Issue 11 2010Anastasia Vyalikh Abstract First-principles quantum mechanical calculations of NMR chemical shifts and quadrupolar parameters have been carried out to assign the 27Al MAS NMR resonances in gibbsite. The 27Al NMR spectrum shows two signals for octahedral aluminum revealing two aluminum sites coordinated by six hydroxyl groups each, although the crystallographic positions of the two Al sites show little difference. The presence of two distinguished 27Al NMR resonances characterized by rather similar chemical shifts but quadrupolar coupling constants differing by roughly a factor of two is explained by different character of the hydrogen bonds, in which the hydroxyls forming the corresponding octahedron around each aluminum site, are involved. The Al-I site characterized by a CQ = 4.6 MHz is surrounded by OHgroups participating in four intralayer and two interlayer hydrogen bonds, while the Al-II site with the smaller quadrupolar constant (2.2 MHz) is coordinated by hydroxides, of which two point toward the intralayer cavities and four OH-bonds are aligned toward the interlayer gallery. In high-resolution solid-state 1H CRAMPS (combination of rotation and multiple-pulse spectroscopy) four signals with an intensity ratio of 1:2:2:1 are resolved which allow to distinguish six nonequivalent hydrogen sites reported in the gibbsite crystal structure and to ascribe them to two types of structural OH groups associated with intralayer and interlayer hydrogen bonds. This study can be applied to characterize the gibbsite-like layer,intergallery interactions associated with hydrogen bonding in the more complex systems, such as synthetic aluminum layered double hydroxides. Copyright © 2010 John Wiley & Sons, Ltd. [source] Upper limits on X-ray emission from two rotating radio transientsMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 3 2009D. L. Kaplan ABSTRACT X-ray emission from the enigmatic rotating radio transients (RRATs) offers a vital clue to understanding these objects and how they relate to the greater neutron star population. An X-ray counterpart to RRAT J1819,1458 is known, and its properties are similar to those of other middle-aged (0.1 Myr) neutron stars. We have searched for X-ray emission with Chandra/Advanced CCD Imaging Spectrometer at the positions of two RRATs with arcsecond (or better) localization, J0847,4316 and J1846,0257. Despite deep searches (especially for RRAT J1846,0257) we did not detect any emission with 0.3,8 keV count-rate limits of 1 and 0.068 counts ks,1, respectively, at 3, confidence. Assuming thermal emission similar to that seen from RRAT J1819,1458 (a blackbody with radius ,20 km), we derive effective temperature limits of 77 and 91 eV for the nominal values of the distances and column densities to both sources, although both of those quantities are highly uncertain and correlated. If we instead fix the temperature of the emission (a blackbody with kT= 0.14 keV), we derive unabsorbed luminosity limits in the 0.3,8 keV range of 1 × 1032 and 3 × 1032 erg s,1. These limits are considerably below the luminosity of RRAT J1819,1458(4 × 1033 erg s,1), suggesting that RRATs J0847,4316 and J1846,0257 have cooled beyond the point of visibility (plausible given the differences in characteristic age). However, as we have not detected X-ray emission, it may also be that the emission from RRATs J0847,4316 and J1846,0257 has a different character from that of RRAT J1819,1458. The two non-detections may prove a counterpoint to RRAT J1819,1458, but more detections are certainly needed before we can begin to derive general X-ray emission properties for the RRAT populations. [source] Zebrafish embryo extracts promote sphere-forming abilities of human melanoma cell lineCANCER SCIENCE, Issue 8 2009Yi-Rang Na Sphere-forming abilities in culture condition are considered a hallmark of cancer stem-like cells, which represents tumor cell invasiveness and stem-like characteristics. We aimed to show that the sphere-forming subpopulation of human malignant melanoma cell line WM-266-4 acts differently to zebrafish embryo extracts compared with their bulk counterpart. Spheres were maintained in neural stem cell culture conditions. The embryos of zebrafish at specific developmental stages were collected and the extracts were purified under 100 kDa. Spheres were treated with embyo extracts and proliferation assay and immunocytochemistry were conducted. Spheroid cells expressed nestin and epidermal growth factor receptor (EGFR) but not melanoma antigen recognized by T-cells (MART)1, indicating their stem-like character. Zebrafish embryo extracts at 50% epiboly stage inhibited melanoma bulk cell proliferation in a dose-dependent manner. However, sphere-forming abilities were significantly enhanced under 1 µg/mL concentration of 50% epiboly stage embryo extract treatment. Our findings implicate that we should consider cell subsets of a different character from the tumor origin that can respond differently to exogenous substances or tumor microenvironments. We suggest that cancer research should consider both minor stem-like subpopulations and the other major bulk tumor cells. (Cancer Sci 2009) [source] Using an Intermediate Skeleton and Inverse Kinematics for Motion RetargetingCOMPUTER GRAPHICS FORUM, Issue 3 2000Jean-Sébastien Monzani In this paper, we present a new method for solving the Motion Retargeting Problem, by using an intermediate skeleton. This allows us to convert movements between hierarchically and geometrically different characters. An Inverse Kinematics engine is then used to enforce Cartesian constraints while staying as close as possible to the captured motion. [source] Comparison of genetic (co)variance matrices within and between Scabiosa canescens and S. columbariaJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 5 2000Waldmann In the current study, we used bootstrap analyses and the common principal component (CPC) method of Flury (1988) to estimate and compare the G -matrix of Scabiosa columbaria and S. canescens populations. We found three major patterns in the G -matrices: (i) the magnitude of the (co)variances was more variable among characters than among populations, (ii) different populations showed high (co)variance for different characters, and (iii) there was a tendency for S. canescens to have higher genetic (co)variances than S. columbaria. The hypothesis of equal G -matrices was rejected in all comparisons and there was no evidence that the matrices differed by a proportional constant in any of the analyses. The two ,species matrices' were found to be unrelated, both for raw data and data standardized over populations, and there was significant between-population variation in the G -matrix in both species. Populations of S. canescens showed conservation of structure (principal components) in their G -matrices, contrasting with the lack of common structure among the S. columbaria matrices. Given these observations and the results from previous studies, we propose that selection may be responsible for some of the variation between the G -matrices, at least in S. columbaria and at the between-species level. [source] A broad transition zone between an inner Baltic hybrid swarm and a pure North Sea subspecies of Macoma balthica (Mollusca, Bivalvia)MOLECULAR ECOLOGY, Issue 6 2008RAISA NIKULA Abstract The populations of the bivalve clam Macoma balthica in the low-salinity Northern Baltic Sea represent an admixture of two strongly diverged genomic origins, the Pacific Macoma balthica balthica (approx. 60% genomic contribution) and Atlantic Macoma balthica rubra (40%). Using allozyme and mtDNA characters, we describe the broad transition from this hybrid swarm to the pure M. b. rubra in the saline North Sea waters, spanning hundreds of kilometre distance. The zone is centred in the strong salinity gradient of the narrow Öresund strait and in the adjacent Western Baltic. Yet the multilocus clines show no simple and smoothly monotonic gradation: they involve local reversals and strong differences between neighbouring populations. The transitions in different characters are not strictly coincident, and the extent of introgression varies among loci. The Atlantic influence extends further into the Baltic in samples from the southern and eastern Baltic coasts than on the western coast, and further in deeper bottoms than at shallow (< 1 m) sites. This fits with the counterclockwise net circulation pattern and with a presumably weaker salinity barrier for invading Atlantic type larvae in saline deeper water, and corresponding facilitation of outwards drift of Baltic larvae in diluted surface waters. Genotypic disequilibria were strong particularly in the shallow-water samples of the steepest transition zone. This suggests larval mixing from different sources and limited interbreeding in that area, which makes a stark contrast to the evidence of thorough amalgamation of the distinct genomic origins in the inner Baltic hybrid swarm of equilibrium structure. [source] Interannual and interpopulation variation in Helichrysum stoechas (Asteraceae), a species of disturbed habitats in the Mediterranean regionPLANT SPECIES BIOLOGY, Issue 1 2001Arnaud Martin Abstract This study examines the interpopulation, interannual and individual variation in Helichrysum stoechas L., a perennial species that colonizes disturbed habitats in the Mediterranean region. The phenotypic variation in five populations was studied. Characters such as plant height and volume, numbers of capitula and flowers, weight of achenes and germination parameters were recorded in situ and in the laboratory for the same individuals for two consecutive years. The data were analyzed to examine the differences between populations and years compared to within-population variation. Results show that the germination rate, the average weight of achenes and the average number of capitula per stem varied considerably from one year to another, independently of population. This year-to-year variation suggests that these traits exhibit phenotypic plasticity. The substantial variation in precipitation during the 2 year study may account for the observed temporal variation. There was some weak correlations between the different characters studied within each population. Significant positive correlations were observed between mean achene weight and the total number of achenes produced per plant and with plant size. [source] Acting up or acting out?LITERACY, Issue 1 2010Unlocking children's talk in literature circles Abstract It is generally accepted that talk enriches children's interpretations of texts in literature circle discussions. However, the nature of that talk and exactly how it facilitates interpretation of texts has not been much analysed. This article describes some work undertaken with a class of Scottish children, aged 9,10, to introduce them to the idea of literature circles. The literature circle discussions were then recorded and analysed. The purpose of the project was to record the kinds of exchanges, chains of comment and range of discourses and voices that children used when talking among themselves, and to reflect on their function and value. It was found that a lot of the talk was exploratory though not always in the sense proposed by Mercer. In his terms much was ,cumulative'. Some talk veered towards anecdotal chat. The children also frequently put on voices not their own, mimicking characters in the story they were reading, and other people they knew. These forms of talk are not always encouraged in the classroom, their effectiveness for learning being in doubt. This article argues that cumulative talk, the telling of anecdotes and the performing of different characters' voices all have a useful function in discussions of books: they can encourage engagement, be helpful in bringing texts to life and advance children's thinking about literature. [source] | |||||||||||||