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Imprint
Kinds of Imprint Terms modified by Imprint Selected AbstractsSEDIMENTARY IMPRINT OF MICROCYSTIS AERUGINOSA (CYANOBACTERIA) BLOOMS IN GRANGENT RESERVOIR (LOIRE, FRANCE),JOURNAL OF PHYCOLOGY, Issue 3 2007Delphine Latour Analysis of a sediment core taken from the Grangent reservoir in 2004 showed the presence of high concentrations of Microcystis aeruginosa Kütz. colonies at the sediment surface (250 colonies,·,mL sediment,1) and also at depths of 25,35 cm (2300 colonies·mL sediment,1) and 70 cm (600 colonies,·,mL sediment,1). Measurements of radioactive isotopes (7Be, 137Cs, and 241Am) along with photographic analysis of the core were used to date the deep layers: the layer located at ,30 cm dates from summer 2003, and that located at ,70 cm from 1990 to 1991. The physiological and morphological conditions of those benthic colonies were compared with those of planktonic colonies using several techniques (environmental scanning electron microscopy [ESEM], TEM, DNA markers, cellular esterases, and toxins). The ESEM observations showed that, as these colonies age, peripheral cells disappear, with no cells remaining in the mucilage of the deepest colonies (70 cm), an indication of the survival thresholds of these organisms. In the benthic phase, the physiological conditions (enzyme activity, cell division, and intracellular toxins) and ultrastructure (particularly the gas vesicles) of the cells surviving in the heart of the colony are comparable to those of the planktonic form, with all the potential needed for growth. Maintaining cellular integrity requires a process that can provide sufficient energy and is expressed in the reduced, but still existing, enzymatic activity that we measured, which is equivalent to a quiescent state. [source] Surface Composition and Imprint in CSD-Based PZT FilmsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 12 2007Aleksey Etin Reports on PZT films often suggest the contradicting presence of Pb-deficient pyrochlore (Py) and a Pb-rich layer on the surface. We show that standard Ar+ ion sputtering X-ray photoelectron spectroscopy (XPS) depth profiles of PZT films artificially exhibit a Pb-rich surface, independent of actual Pb content of the chemical solution deposition solution. However angle-resolved XPS measurements reveal that films derived from solutions with 10% Pb excess, which give rise to Py surface grains, actually have the expected Pb-deficient surface layer. Alternatively, films derived from solutions with 30% Pb excess are Py free and have Pb-rich surface layer. The Pb-rich films show an increased imprint effect with increasing Pb content. [source] Polymer Films Composed of Surface-Bound Nanofilaments with a High Aspect Ratio, Molecularly Imprinted with Small Molecules and ProteinsADVANCED FUNCTIONAL MATERIALS, Issue 8 2009Ana Valvanuz Linares Abstract Hierarchically nanostructured materials that combine two or more levels of structuring and that exhibit a combination of useful features have gained considerable interest over recent years. Here, the generation of surface-bound nanofilaments with a high aspect ratio by nanomolding on a nanoporous template surface is described. The filaments, at the same time, carry molecularly imprinted binding sites. The dye fluorescein and the protein myoglobin are used as model templates for imprinting. The surfaces exhibit specific binding as revealed by fluorescence microscopy. The wetting properties of the surfaces depend on the dimensions of the nanofilaments and on the nature of the polymer. It is believed that these materials can potentially be useful for applications in biosensors and biochips. [source] A Room Temperature Ionic Liquid (RTIL)-Mediated, Non-Hydrolytic Sol,Gel Methodology to Prepare Molecularly Imprinted, Silica-Based Hybrid Monoliths for Chiral Separation,ADVANCED MATERIALS, Issue 24 2006H.-F. Wang Silica-based hybrid molecularly imprinted polymer (MIP) monoliths with good chiral recognition ability are synthesized (see figure) using a novel method, a room temperature ionic liquid (RTIL)-mediated, non-hydrolytic sol,gel technique. The approach avoids the cracking and shrinking of the bed during drying, which is commonly associated with conventional sol,gel processing, overcomes the shortcomings associated with conventional organic-polymer-based MIP matrices, and offers improved selectivity. [source] Bacterial translocation in a non-lethal rat model of peritonitisCOLORECTAL DISEASE, Issue 5 2001V. Yao Background Bacterial translocation from the gut may occur under a variety of different clinical circumstances and has been implicated in the development of multiple organ failure. The aim of this study was to determine the distribution of bacterial translocation occurring in a model of chemically induced peritonitis. We also sought to document the degree of the associated immune and inflammatory response. Methods Though a midline laparotomy, rats were injected with 5 mg of zymosan (in 0.2 ml of saline) into the subomental space. After 4, 18, 24, 48 and 96 h, a number of endpoints evaluated: intraperitoneal cellular influx, TNF-, and interleukin-6 concentrations and myeloperoxidase activity. Bacterial cultures were initiated from the free peritoneal fluid, mesenteric lymph nodes, liver, lung, and kidney. Imprints were also made of the peritoneal mesothelial surface to determine its integrity. Results When comparing rats injected with zymosan with the controls, there was evidence of a peritoneal inflammatory response within 4 hours. Facultative gram negative bacteria were found to be growing in the mesenteric lymph nodes and in the peritoneal fluid at 48 h. Anaerobic organisms were also cultured from the peritoneal fluid at 48 h. No organisms were cultured from the liver, lung or kidneys. In addition there was a significant increase in intraperitoneal cell numbers (predominantly neutrophils, P < 0.05), myeloperoxidase activity (P < 0.05) and TNF-, and IL-6 concentrations (P < 0.05). There was extensive loss of the peritoneal mesothelial cells. The peritoneal inflammatory changes and bacterial translocation had resolved by 96 h. Conclusion Bacterial translocation can be induced by the presence of an acute inflammatory focus in the peritoneal cavity. The translocation and inflammatory changes were associated with extensive loss of mesothelial cells. Nonetheless, these changes all resolved, indicating that the peritoneal cavity has a significant capacity to deal with such insults. A clearer understanding of the cellular and molecular events involved in the resolution phase could lead to improvements in the treatment of peritonotis. [source] Intraoperative cytology of clear cell carcinoma of the ovaryCYTOPATHOLOGY, Issue 6 2006D. Vrdoljak-Mozeti Objective:, To describe the cytomorphology of clear cell carcinoma (CCC) of the ovary in intraoperative samples of peritoneal fluid, imprint and scraping samples of the tumour tissue. Study design:, Fourteen histologically confirmed cases, stained by standard cytological procedures, were analysed by light microscopy. Results:, In 33.3% of peritoneal fluid samples and 92.9% of imprint and scraping cytological samples, besides variable clear cell cellular morphology, one or both distinct cytological characteristics were observed: eosinophilic, hyaline, extracellular, globular substance with or without formation of a ,raspberry' body and an eosinophilic, intracytoplasmic inclusions. These structures were clearly seen only in samples stained by May-Grünwald,Giemsa. Conclusion:, Using cytological analysis of imprint and scraping samples of ovarian tumours it is possible to make a precise intraoperative cytological diagnosis in most cases of CCC of the ovary. [source] Role of ancillary techniques in diagnosing and subclassifying non-Hodgkin's lymphomas on fine needle aspiration cytologyCYTOPATHOLOGY, Issue 5 2006P. DeyArticle first published online: 8 SEP 200 Non-Hodgkin's lymphomas (NHL) are tumours of the lymphoid cells. During the process of development of lymphoid cells, neoplasia may evolve at any point. Neoplastic cells usually carry the imprint of cell of origin at the stage of origin. Various types of NHL may have similar morphology with wide variation in origin, immunophenotype and other biological features. Different ancillary laboratory techniques may help to overcome the limitations of morphology in this aspect. The commonly used ancillary techniques in lymphomas are immunocytochemistry (IC), flow cytometry, Southern blot (SB) technique, polymerase chain reaction (PCR) and fluorescent in situ hybridization (FISH). In addition, laser scanning cytometry (LSC) and DNA microarray technologies are in the research phase. Various laboratory techniques are used for immunophenotyping, demonstration of monoclonality, identification of chromosomal translocation, assessment of cell kinetics and expression of mRNA in the tumour cells. Flow cytometry helps in rapid immunophenotying of NHL and it has an added advantage over IC in recognizing the co-expression of CD markers. Fine needle aspiration cytology (FNAC) combined with flow immunophenotyping may help us to diagnose and subclassify certain NHLs, such as follicular lymphoma and mantle cell lymphoma, which were previously recognized as pure morphological entities. Loss of morphology is one of the important limitations of flow cytometry. LSC can overcome this limitation by studying morphology along with the immunophenotyping pattern of individual cells. Chromosomal changes in NHL can be identified by SB, PCR and FISH. Molecular diagnosis of NHL helps in diagnosis, subclassification, prognostic assessment and even in planning of therapy. DNA microarray is a relatively newer and promising technology. It gives information about the expression of several thousands of genes in a tumour in a single experiment. In the near future, FNAC combined with ancillary techniques may play a major role in diagnosis, subclassification and management of lymphomas. [source] Cytologic features of meningiomas on crush preparations: A reviewDIAGNOSTIC CYTOPATHOLOGY, Issue 4 2008F.I.A.C., Momin T. Siddiqui M.D. Abstract Meningiomas are rarely subjected to aspiration, however, since they may occur outside the central nervous system, it is important to recognize their cytologic features. The goal of this study was to examine the cytologic features of meningiomas in crush preparations and cytologic imprints prepared at the time of frozen section. A total of 97 cases of meningiomas evaluated intraoperatively by frozen section with concomitant crush preparation and cytologic imprint were reviewed to assess their cytologic features. The cytologic features of meningiomas identified in our study are cohesive syncitial clusters of cells with ill-defined boundaries. The nuclei are oval and may be eccentrically placed, along with small central nucleoli. The cytologic features may not reflect the histologic subtype. The psammomatous variant can however be easily recognized in touch preps/imprints. The presence of nuclear anaplasia, macronucleoli, mitotic activity, and sheet-like growth may suggest an atypical meningioma. In conclusion, the cytologic features identified would be helpful in diagnosis of meningiomas, especially in unusual locations. Diagn. Cytopathol. 2008;36:202,206. © 2008 Wiley-Liss, Inc. [source] Human impacts on the species,area relationship in reef fish assemblagesECOLOGY LETTERS, Issue 9 2007Derek P. Tittensor Abstract The relationship between species richness and area is one of the oldest, most recognized patterns in ecology. Here we provide empirical evidence for strong impacts of fisheries exploitation on the slope of the species,area relationship (SAR). Using comparative field surveys of fish on protected and exploited reefs in three oceans and the Mediterranean Sea, we show that exploitation consistently depresses the slope of the SAR for both power-law and exponential models. The magnitude of change appears to be proportional to fishing intensity. Results are independent of taxonomic resolution and robust across coral and rocky reefs, sampling protocols and statistical methods. Changes in species richness, relative abundance and patch occupancy all appear to contribute to this pattern. We conclude that exploitation pressure impacts the fundamental scaling of biodiversity as well as the species richness and spatial distribution patterns of reef fish. We propose that species,area curves can be sensitive indicators of community-level changes in biodiversity, and may be useful in quantifying the human imprint on reef biodiversity, and potentially elsewhere. [source] Personality profiles of cultures: Patterns of ethos,EUROPEAN JOURNAL OF PERSONALITY, Issue 3 2009Robert R. McCrae Abstract Culture and the human mind are deeply interdependent, because they co-evolved. Personality traits were a preexisting feature of the primate mind and must have left an imprint on forms of culture. Trait taxonomies can structure ethnographies, by specifying institutions that reflect the operation of traits. Facets of ethos can be assessed by expert ratings or objective indicators. Ratings of ethos in Japan and the US were reliable and yielded plausible descriptions of culture. However, measures of ethos based on the analysis of stories were not meaningfully correlated with aggregate personality traits or national character stereotypes. Profiles of ethos may provide another axis that can be used with aggregate personality trait levels to predict behaviour and understand the operation of culture. Published in 2009 by John Wiley & Sons, Ltd. [source] EVOLUTIONARY CONSTRAINT AND ECOLOGICAL CONSEQUENCESEVOLUTION, Issue 7 2010Douglas J. Futuyma One of the most important shifts in evolutionary biology in the past 50 years is an increased recognition of sluggish evolution and failures to adapt, which seem paradoxical in view of abundant genetic variation and many instances of rapid local adaptation. I review hypotheses of evolutionary constraint (or restraint), and suggest that although constraints on individual characters or character complexes may often reside in the structure or paucity of genetic variation, organism-wide stasis, as described by paleontologists, might better be explained by a hypothesis of ephemeral divergence, according to which the spatial or temporal divergence of populations is often short-lived because of interbreeding with nondivergent populations. Among the many consequences of acknowledging evolutionary constraints, community ecology is being transformed as it takes into account phylogenetic niche conservatism and the strong imprint of deep history. [source] How Did the 2003 Dividend Tax Cut Affect Stock Prices?FINANCIAL MANAGEMENT, Issue 4 2008Gene Amromin We test the hypothesis that the 2003 dividend tax cut boosted US stock prices and thereby lowered the cost of equity capital. Using an event-study methodology, we attempt to identify an aggregate stock market effect by comparing the behavior of US common stock prices with that of foreign equities and the equities of real estate investment trusts (REITs). We also examine the relative cross-sectional response of prices of high- and low-dividend-paying stocks. We do not find any imprint of the dividend tax cut news on the value of the aggregate US stock market. On the other hand, high-dividend stocks outperformed low-dividend stocks by a few percentage points over the event windows, suggesting that the tax cut may have induced asset reallocation within equity portfolios. Finally, the positive abnormal return on nondividend paying US stocks in 2003 does not appear to be tied to tax cut news. [source] De Novo DNA methylation independent establishment of maternal imprint on X chromosome in mouse oocytesGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 12 2008Hatsune Chiba Mouse blastocyst stage embryo stained for histone H3 lysine-27 trimethylation (red) and DNA (blue). H3K27me3 marks the inactive X chromosome. The study by Chiba et al. in this issue suggests that de novo DNA methyltransferases are dispensable for setting the imprint on the maternally-derived X chromsome in growing oocytes. See Chiba et al. in this issue. [source] Ordered High-Density Si [100] Nanowire Arrays Epitaxially Grown by Bottom Imprint MethodADVANCED MATERIALS, Issue 27 2009Zhang Zhang A novel bottom imprint method to fabricate high-quality Si [100] nanowire arrays is demonstrated. This new approach combines the functions of a high-ordering AAO template as a stamp and template simultaneously. By the protective polymer layer in the hot imprint, the vertical 40,nm Si nanowire arrays grow epitaxially on the Si substrate with a narrow size distribution [source] Source signature and elastic waves in a half-space under a sustainable line-concentrated impulsive normal forceINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 4 2002Moche Ziv Abstract First, the response of an ideal elastic half-space to a line-concentrated impulsive normal load applied to its surface is obtained by a computational method based on the theory of characteristics in conjunction with kinematical relations derived across surfaces of strong discontinuities. Then, the geometry is determined of the obtained waves and the source signature,the latter is the imprint of the spatiotemporal configuration of the excitation source in the resultant response. Behind the dilatational precursor wave, there exists a pencil of three plane waves extending from the vertex at the impingement point of the precursor wave on the stress-free surface of the half-space to three points located on the other two boundaries of the solution domain. These four wave-arresting points (end points) of the three plane waves constitute the source signature. One wave is an inhibitor front in the behaviour of the normal stress components and the particle velocity, while in the behaviour of the shear stress component, it is a surface-axis wave. The second is a surface wave in the behaviour of the horizontal components of the dependent variables, while the third is an inhibitor wave in the behaviour of the shear stress component. An inhibitor wave is so named, since beyond it, the material motion is dying or becomes uniform. A surface-axis wave is so named, since upon its arrival, like a surface wave, the dependent variable in question features an extreme value, but unlike a surface wave, it exists in the entire depth of the solution domain. It is evident from this work that Saint-Venant's principle for wave propagation problems cannot be formulated; therefore, the above results are a consequence of the particular model proposed here for the line-concentrated normal load. Copyright © 2002 John Wiley & Sons, Ltd. [source] An imprint and merge algorithm incorporating geometric tolerances for conformal meshing of misaligned assembliesINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 14 2004David R. White Abstract A size tolerant algorithm for imprinting and merging adjacent part geometries is presented in this paper. This approach cleans up misaligned and dirty assembly geometry that is intended for conformal mesh generation. The algorithm first discretizes the boundary edges of adjacent faces into linear segments. The segments are then intersected and a partial intersection graph is calculated from the intersection results. The intersections are calculated by accounting for size tolerances to minimize the effect of misaligned parts on the meshing process. The partial intersection graph is next used to imprint the adjacent faces as appropriate. The imprints are generated using virtual geometry so that the tolerant topology created therein can be employed. Several examples are given to demonstrate the resulting improvement in the mesh quality of conformal meshes. The approach is shown to work robustly with misaligned and poorly defined parts. Copyright © 2004 John Wiley & Sons, Ltd. [source] X-linked mental retardation and epigeneticsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 4 2006Guy Froyen Abstract The search for the genetic defects in constitutional diseases has so far been restricted to direct methods for the identification of genetic mutations in the patients' genome. Traditional methods such as karyotyping, FISH, mutation screening, positional cloning and CGH, have been complemented with newer methods including array-CGH and PCR-based approaches (MLPA, qPCR). These methods have revealed a high number of genetic or genomic aberrations that result in an altered expression or reduced functional activity of key proteins. For a significant percentage of patients with congenital disease however, the underlying cause has not been resolved strongly suggesting that yet other mechanisms could play important roles in their etiology. Alterations of the ,native' epigenetic imprint might constitute such a novel mechanism. Epigenetics, heritable changes that do not rely on the nucleotide sequence, has already been shown to play a determining role in embryonic development, X-inactivation, and cell differentiation in mammals. Recent progress in the development of techniques to study these processes on full genome scale has stimulated researchers to investigate the role of epigenetic modifications in cancer as well as in constitutional diseases. We will focus on mental impairment because of the growing evidence for the contribution of epigenetics in memory formation and cognition. Disturbance of the epigenetic profile due to direct alterations at genomic regions, or failure of the epigenetic machinery due to genetic mutations in one of its components, has been demonstrated in cognitive derangements in a number of neurological disorders now. It is therefore tempting to speculate that the cognitive deficit in a significant percentage of patients with unexplained mental retardation results from epigenetic modifications. [source] A simple and versatile protocol for the preparation of 1,3-functionalized heterocycles utilizing benzoylpyruvatesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 4 2010Jens M. J. Nolsöe Acid-mediated condensation between benzoylpyruvates and various dinucleophiles in alcoholic solvent furnished the heterocyclic imprint in moderate to good yield. Combining a range of symmetric as well as nonsymmetric nitrogen/nitrogen or nitrogen/carbon centered dinucleophiles resulted in excellent regioselectivity. ,-Difunctionalized fused pyrimidines, pyridazines, and pyridines were produced in this manner. The protocol was designed to obviate chromatographic purification. J. Heterocyclic Chem., (2010). [source] The Denial of Slavery in Management StudiesJOURNAL OF MANAGEMENT STUDIES, Issue 8 2003Bill Cooke abstract American slavery has been wrongfully excluded from histories of management. By 1860, when the historical orthodoxy has modern management emerging on the railroads, 38,000 managers were managing the 4 million slaves working in the US economy. Given slaves' worth, slaveholders could literally claim ,our people are our greatest asset.' Yet a review of histories of management shows ante-bellum slavery excluded from managerial modernity as pre-capitalist, unsophisticated in practice, and without non-owner managers identified as such. These grounds for exclusion are challenged. First, it is shown slavery is included within capitalism by many historians, who also see plantations as a site of the emergence of industrial discipline. Second, ante-bellum slavery is demonstrated to have been managed according to classical management and Taylorian principles. Third, those doing the managing are shown to have been employed at the time as ,managers'. In the idea of the manager, and of scientific and classical management slavery has therefore left an ongoing imprint in management practice and thought. A strong argument is made for not just for postcolonialist accounts of management, but for management histories in which anti-African-American racism is a continuing strand. The fundamental significance of the article however is its identification of slavery as of intrinsic, but hitherto denied, relevance to management studies. [source] Synthesis and characterization of hyperbranched polymers with increased chemical versatility for imprint lithographic resistsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 18 2008Anzar Khan Abstract Hyperbranched polymers were prepared from a variety of mono- and difunctional monomers and used in the development of novel UV-imprint lithography (UV-IL) resists. The unique physical and chemical properties of these hyperbranched materials significantly increase the range of molecular systems that could be imprinted. Traditional challenges, such as the use of monomers that have low boiling points or the use of insoluble/highly crystalline momomers, are overcome by the preparation of hyperbranched polymers that incorporate these repeat units. In addition, the low viscosity of the hyperbranched macromolecules and the large number of reactive chain ends overcome many difficulties that are traditionally associated with the use of polymeric materials as imprint resists. Hyperbranched polymers containing up to 12 mol % pendant vinyl groups, needed for secondary crosslinking during imprinting, were prepared with a wide range of repeat unit structures and successfully imprinted with features from tens of microns to , 100 nm. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6238,6254, 2008 [source] The communication of meaning and the structuration of expectations: Giddens' "structuration theory" and Luhmann's "self-organization"JOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 10 2010Loet Leydesdorff The communication of meaning as distinct from (Shannon-type) information is central to Luhmann's social systems theory and Giddens' structuration theory of action. These theories share an emphasis on reflexivity, but focus on meaning along a divide between interhuman communication and intentful action as two different systems of reference. Recombining these two theories into a theory about the structuration of expectations, interactions, organization, and self-organization of intentional communications can be simulated based on algorithms from the computation of anticipatory systems. The self-organizing and organizing layers remain rooted in the double contingency of the human encounter, which provides the variation. Organization and self-organization of communication are reflexive upon and therefore reconstructive of each other. Using mutual information in three dimensions, the imprint of meaning processing in the modeling system on the historical organization of uncertainty in the modeled system can be measured. This is shown empirically in the case of intellectual organization as "structurating" structure in the textual domain of scientific articles. [source] A four-fold humanity: Margaret Mead and psychological typesJOURNAL OF THE HISTORY OF THE BEHAVIORAL SCIENCES, Issue 2 2004Gerald SullivanArticle first published online: 19 MAR 200 Beginning in 1933, while working in New Guinea, Margaret Mead developed her so-called squares hypothesis. Mead never published its terms, though she made a brief comment on it in her autobiography, Blackberry Winter (1972), and the arguments found in Sex and Temperament in Three Primitive Societies (1935) and the research leading to Balinese Character (Bateson & Mead, 1942) bore its imprint. Beginning with William McDougall's distinction between temperament (innate predispositions) and character (learned organization of habit), Mead articulated a morphological approach to the interplay between biology and culture that yielded four primary and four intermediary personality types. Under specified but not inevitable circumstances, the conscious choices of a given people could render one or another of these types characteristic or predominantly stable within their population, giving each of the other types a definite relation to the dominant type and thereby the cultural ethos of its society. Persons of each type followed a developmental path specific to their type different both from that of other types and in its manifestations given the various relations of the individual's type to the dominant type. Mead's hypothesis was, therefore, a vision of the unity and diversity of a single human species as well as an approach to the differing psychological positioning of individuals in cultures. In examining Mead's hypothesis, this essay also takes up Mead's debts to several leading psychologists (McDougall, C. G. Jung, and Erik Erikson), and (provisionally) how her vision differed from that of Ruth Benedict. © 2004 Wiley Periodicals, Inc. [source] Ever deeper phylogeographies: trees retain the genetic imprint of Tertiary plate tectonicsMOLECULAR ECOLOGY, Issue 24 2007ARNDT HAMPE Changes in species distributions after the last glacial maximum (c. 18 000 years bp) are beginning to be understood, but information diminishes quickly as one moves further back in time. In this issue of Molecular Ecology, Magri et al. (2007) present the fascinating case of a Mediterranean tree species whose populations preserve the genetic imprints of plate tectonic events that took place between 25 million years and 15 million years ago. The study provides a unique insight into the pace of evolution of trees, which, despite interspecific gene flow, can retain a cohesive species identity over timescales long enough to allow the diversification of entire plant and animal genera. [source] Superfluid signatures in magnetar seismologyMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2009N. Andersson ABSTRACT We investigate the role of neutron star superfluidity for magnetar oscillations. Using a plane-wave analysis, we estimate the effects of a neutron superfluid in the elastic crust region. We demonstrate that the superfluid imprint is likely to be more significant than the effects of the crustal magnetic field. We also consider the region immediately beneath the crust, where superfluid neutrons are thought to coexist with a type II proton superconductor. Since the magnetic field in the latter is carried by an array of fluxtubes, the dynamics of this region differ from standard magnetohydrodynamics. We show that the presence of the neutron superfluid (again) leaves a clear imprint on the oscillations of the system. Taken together, our estimates show that the superfluid components cannot be ignored in efforts to carry out ,magnetar seismology'. This increases the level of complexity of the modelling problem, but also points to the possibility of using observations to probe the superfluid nature of supranuclear matter. [source] Gemini near-infrared integral field spectroscopy of the narrow-line region of ESO 428,G14: kinematics, excitation and the role of the radio jetMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2006Rogemar A. Riffel ABSTRACT We present two-dimensional (2D) gas kinematics and excitation of the inner 300 pc of the Seyfert galaxy ESO 428,G14 at a sampling of 14 pc2, from near-infrared spectroscopic observations at R, 6000 obtained with the Integral Field Unit (IFU) of the Gemini Near-Infrared Spectrograph. From measurements of fluxes and profiles of the emission lines [Fe ii],1.257 ,m, Pa,, H2, 2.121 ,m and Br,, we construct 2D maps of line intensities and ratios, radial velocities and velocity dispersions. Emission line ,tomography' is provided by velocity slices obtained across the line profiles, a unique capability of IFUs, which allows the mapping of not only the peak velocities but including also the wings. We compare these maps with a previously published high spatial resolution radio map and find a tight relation between the radio structure and the emission-line flux distributions and kinematics, revealing that the radio jet plays a fundamental role not only in shaping the narrow-line region but also in the imprint of its kinematics. Blueshifts of up to 400 km s,1 and velocity dispersions of up to 150 km s,1 are observed in association with the radio jet at a position angle (PA) = 129°, which is also the PA of the photometric major axis of the galaxy. We conclude that the radio jet is launched at a small angle relative to the galactic plane, with the north-western side slightly oriented towards us. This angle is small enough for the radio jet to shock and compress the gas in the plane of the galaxy, and for the nuclear continuum to ionize and heat it. The distinct kinematics and flux distributions observed for the different emission lines suggest different origins for their emission. The [Fe ii] shows the largest blueshifts and velocity dispersions and its flux distribution is concentrated along the jet, while the H2 shows the lowest velocity dispersions and has additional flux contribution from regions beyond the jet. Both X-rays emitted by the active galactic nucleus and shocks produced by the radio jet can excite the H2 and [Fe ii] emission lines. We use the 2D velocity dispersion maps to estimate upper limits to the contribution of the radio jet to the excitation of [Fe ii] and H2 which may reach 90 per cent for [Fe ii] and 80 per cent for H2 in the jet region. The [Fe ii]/Pa, emission-line ratios and the association of the [Fe ii] flux distribution and kinematics with the radio structure support a stronger contribution of the radio jet to the [Fe ii] excitation than that of H2. In the regions beyond the jet, the observations favour X-ray excitation. [source] On the effect of neglecting anharmonic nuclear motion in charge density studiesACTA CRYSTALLOGRAPHICA SECTION A, Issue 3 2010Kathrin Meindl The effect of neglecting anharmonic nuclear motion when it is definitely present is studied. To ensure the presence of anharmonic nuclear motion a model was used that was previously refined against experimental data including anharmonic nuclear motion, and these calculated structure factors were used as observed data for a multipole refinement. It was then studied how the neglect of anharmonic nuclear motion and noise in the data affects the usual crystallographic quality measure R, the density parameters and the residual density distribution. It is demonstrated that the neglect of anharmonic nuclear motion leads to a characteristic imprint onto the residual density distribution in terms of residual density peaks and holes, in terms of the whole residual density distribution and in terms of the number, location and strength of valence shell charge concentrations (VSCCs). These VSCCs differ from that of the input model in a way which heavily influences and misleads the chemical interpretation of the charge density. This imprint vanishes after taking anharmonic nuclear motion into account. Also the input model VSCCs are restored. The importance of modeling anharmonic nuclear motion is furthermore shown by the characteristic imprint on the residual density distribution, even in the case of a numerically almost unaffected R value. [source] Mechanisms of imprint dysregulation,AMERICAN JOURNAL OF MEDICAL GENETICS, Issue 3 2010Bernhard Horsthemke Abstract Genomic imprinting is an epigenetic process by which the male and the female germ line confer specific marks (imprints) onto certain gene regions, so that one allele of an imprinted gene is active and the other allele is silent. Genomic imprints are erased in primordial germ cells, newly established during later stages of germ cell development, and stably inherited through somatic cell divisions during postzygotic development. Defects in imprint erasure, establishment, or maintenance result in a paternal chromosome carrying a maternal imprint or in a maternal chromosome carrying a paternal imprint. A wrong imprint leads to activation of an allele that should be silent or silencing of an allele that should be active. Since the dosage of imprinted genes is very important for development and growth, imprinting defects lead to specific diseases. Imprinting defects can occur spontaneously without any DNA sequence change (primary imprinting defect) or as the result of a mutation in a cis -regulatory element or a trans -acting factor (secondary imprinting defect). The distinction between primary and secondary imprinting defects is important for assessing the recurrence risk in affected families. © 2010 Wiley-Liss, Inc. [source] Experimentally generated footprints in sand: Analysis and consequences for the interpretation of fossil and forensic footprintsAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2010K. D'Août Abstract Fossilized footprints contain information about the dynamics of gait, but their interpretation is difficult, as they are the combined result of foot anatomy, gait dynamics, and substrate properties. We explore how footprints are generated in modern humans. Sixteen healthy subjects walked on a solid surface and in a layer of fine-grained sand. In each condition, 3D kinematics of the leg and foot were analyzed for three trials at preferred speed, using an infrared camera system. Additionally, calibrated plantar pressures were recorded. After each trial in sand, the depth of the imprint was measured under specific sites. When walking in sand, subjects showed greater toe clearance during swing and a 7° higher knee yield during stance. Maximal pressure was the most influential factor for footprint depth under the heel. For other foot zones, a combination of factors correlates with imprint depth, with pressure impulse (the pressure-time integral) gaining importance distally, at the metatarsal heads and the hallux. We conclude that footprint topology cannot be related to a single variable, but that different zones of the footprint reflect different aspects of the kinesiology of walking. Therefore, an integrated approach, combining anatomical, kinesiological, and substrate-mechanical insights, is necessary for a correct interpretation. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] Post-last glacial maximum expansion from Iberia to North Africa revealed by fine characterization of mtDNA H haplogroup in TunisiaAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2009Lotfi Cherni Abstract The first large-scale fine characterization of Tunisian H lineages clarifies that the post-Last glacial maximum expansion originating in Iberia not only led to the resettlement of Europe but also of North Africa. We found that 46% of 81 Tunisian H lineages subscreened for 1,580 bp in mtDNA coding region were affiliated with H1 and H3 subhaplogroups, which are known to have originated in Iberia. Although no signs of local expansion were detected, which would allow a clear dating of their introduction, the younger and less diverse Tunisian H1 and H3 lineages indicate Iberia as the radiating centre. Major contributions from historical migrations to this Iberian genetic imprint in Tunisia were ruled out by the mtDNA gene pool similarity between Berber/Arab/cosmopolitan samples and some "Andalusian" communities, settled by the descendents of the "Moors" who once lived in Iberia for 10 centuries (between 8th and 17th centuries), before being expelled to Tunisia. Am J Phys Anthropol, 2009. © 2008 Wiley-Liss, Inc. [source] Diversity of Mitochondrial DNA Lineages in South SiberiaANNALS OF HUMAN GENETICS, Issue 5 2003M. V. Derenko Summary To investigate the origin and evolution of aboriginal populations of South Siberia, a comprehensive mitochondrial DNA (mtDNA) analysis (HVR1 sequencing combined with RFLP typing) of 480 individuals, representing seven Altaic-speaking populations (Altaians, Khakassians, Buryats, Sojots, Tuvinians, Todjins and Tofalars), was performed. Additionally, HVR2 sequence information was obtained for 110 Altaians, providing, in particular, some novel details of the East Asian mtDNA phylogeny. The total sample revealed 81% East Asian (M*, M7, M8, M9, M10, C, D, G, Z, A, B, F, N9a, Y) and 17% West Eurasian (H, U, J, T, I, N1a, X) matrilineal genetic contribution, but with regional differences within South Siberia. The highest influx of West Eurasian mtDNAs was observed in populations from the East Sayan and Altai regions (from 12.5% to 34.5%), whereas in populations from the Baikal region this contribution was markedly lower (less than 10%). The considerable substructure within South Siberian haplogroups B, F, and G, together with the high degree of haplogroup C and D diversity revealed there, allows us to conclude that South Siberians carry the genetic imprint of early-colonization phase of Eurasia. Statistical analyses revealed that South Siberian populations contain high levels of mtDNA diversity and high heterogeneity of mtDNA sequences among populations (Fst = 5.05%) that might be due to geography but not due to language and anthropological features. [source] | |||||||||||||||||||||||||||||||||||||