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Unique Insight (unique + insight)
Selected AbstractsProbing Noncovalent Interactions in Biomolecular Crystals with Terahertz SpectroscopyCHEMPHYSCHEM, Issue 4 2008Thomas Kleine-Ostmann Dr. Unique insights: The complexities of intermolecular interactions within biomolecular crystals (see figure, solid state thymine) are studied using a combination of spectroscopic and quantum-chemical techniques. Insights into the fundamental nature of the various low-frequency peaks is achieved and intra- vs intermolecular modes are distinguished. [source] MR imaging methods for assessing fetal brain developmentDEVELOPMENTAL NEUROBIOLOGY, Issue 6 2008Mary Rutherford Abstract Fetal magnetic resonance imaging provides an ideal tool for investigating growth and development of the brain in vivo. Current imaging methods have been hampered by fetal motion but recent advances in image acquisition can produce high signal to noise, high resolution 3-dimensional datasets suitable for objective quantification by state of the art post acquisition computer programs. Continuing development of imaging techniques will allow a unique insight into the developing brain, more specifically process of cell migration, axonal pathway formation, and cortical maturation. Accurate quantification of these developmental processes in the normal fetus will allow us to identify subtle deviations from normal during the second and third trimester of pregnancy either in the compromised fetus or in infants born prematurely. © 2008 Wiley Periodicals, Inc. Develop Neurobiol, 2008 [source] AN EXACT FORM OF THE BREEDER'S EQUATION FOR THE EVOLUTION OF A QUANTITATIVE TRAIT UNDER NATURAL SELECTIONEVOLUTION, Issue 11 2005John S. Heywood Abstract Starting with the Price equation, I show that the total evolutionary change in mean phenotype that occurs in the presence of fitness variation can be partitioned exactly into five components representing logically distinct processes. One component is the linear response to selection, as represented by the breeder's equation of quantitative genetics, but with heritability defined as the linear regression coefficient of mean offspring phenotype on parent phenotype. The other components are identified as constitutive transmission bias, two types of induced transmission bias, and a spurious response to selection caused by a covariance between parental fitness and offspring phenotype that cannot be predicted from parental phenotypes. The partitioning can be accomplished in two ways, one with heritability measured before (in the absence of) selection, and the other with heritability measured after (in the presence of) selection. Measuring heritability after selection, though unconventional, yields a representation for the linear response to selection that is most consistent with Darwinian evolution by natural selection because the response to selection is determined by the reproductive features of the selected group, not of the parent population as a whole. The analysis of an explicitly Mendelian model shows that the relative contributions of the five terms to the total evolutionary change depends on the level of organization (gene, individual, or mated pair) at which the parent population is divided into phenotypes, with each frame of reference providing unique insight. It is shown that all five components of phenotypic evolution will generally have nonzero values as a result of various combinations of the normal features of Mendelian populations, including biparental sex, allelic dominance, inbreeding, epistasis, linkage disequilibrium, and environmental covariances between traits. Additive genetic variance can be a poor predictor of the adaptive response to selection in these models. The narrow-sense heritability s,2A/s,2P should be viewed as an approximation to the offspring-parent linear regression rather than the other way around. [source] Globalization and the Boundaries of the State: A Framework for Analyzing the Changing Practice of SovereigntyGOVERNANCE, Issue 1 2001Edward S. Cohen The impact of globalization on the sovereignty of the modern state has been a source of great controversy among political scientists. In this article, I offer a framework for understanding the state as a boundary-setting institution, which changes shape and role over time and place. I argue that, rather than undermining the state, globalization is a product of a rearrangement of the purposes, boundaries, and sovereign authority of the state. Focusing on the United States, the article traces the changing shape of state sovereignty through a study of the patterns of immigration policy and politics over the past three decades. Immigration policy, I argue, provides a unique insight into the continuities and changes in the role of the state in an era of globalization. [source] Celluloid angels: a research study of nurses in feature films 1900,2007JOURNAL OF ADVANCED NURSING, Issue 1 2008David J. Stanley Abstract Title.,Celluloid angels: a research study of nurses in feature films 1900,2007. Aim., This paper is a report of a study examining the influence on how nursing and nurses are portrayed in feature films made between 1900 and 2007, with a nurse as their main or a principle character and a story-line related specifically to nursing. Background., Nurses and the nursing profession are frequently portrayed negatively or stereotypically in the media, with nurses often being portrayed as feminine and caring but not as leaders or professionals capable of autonomous practice. Methods., A mixed method approach was used to examine feature films made in the Western world. Over 36,000 feature film synopses were reviewed (via CINAHL, ProQuest and relevant movie-specific literature) for the keywords ,nurse'/,nursing'. Identified films were analysed quantitatively to determine their country of production, genre, plot(s) and other relevant data, and qualitatively to identify the emergence of themes related to the image of nurses/nursing in films. Findings., For the period from 1900 to 2007, 280 relevant feature films were identified. Most films were made in the United States of America or United Kingdom, although in recent years films have been increasingly produced in other countries. Early films portrayed nurses as self-sacrificial heroines, sex objects and romantics. More recent films increasingly portray them as strong and self-confident, professionals. Conclusion., Nurse-related films offer a unique insight into the image of nurses and how they have been portrayed. Nurses need to be aware of the impact the film industry has on how nurses and nursing are perceived and represented in feature films. [source] In Vivo Determination of Bone Structure in Postmenopausal Women: A Comparison of HR-pQCT and High-Field MR Imaging,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2008Galateia J Kazakia PhD Abstract Bone structural measures obtained by two noninvasive imaging tools,3T MRI and HR-pQCT,were compared. Significant but moderate correlations and 2- to 4-fold discrepancies in parameter values were detected, suggesting that differences in acquisition and analysis must be considered when interpreting data from these imaging modalities. Introduction: High-field MRI and high resolution (HR)-pQCT are currently being used in longitudinal bone structure studies. Substantial differences in acquisition and analysis between these modalities may influence the quantitative data produced and could potentially influence clinical decisions based on their results. Our goal was to compare trabecular and cortical bone structural measures obtained in vivo by 3T MRI and HR-pQCT. Materials and Methods: Postmenopausal osteopenic women (n = 52) were recruited for this study. HR-pQCT imaging of the radius and tibia was performed using the XtremeCT scanner, with a voxel size of 82 × 82 × 82 ,m3. MR imaging was performed on a 3T Signa scanner using SSFP imaging sequences, with a pixel size of 156 × 156 ,m2 and slice thickness of 500 ,m. Structure parameters were calculated using standard HR-pQCT and MRI analysis techniques. Relationships between measures derived from HR-pQCT, MRI, and DXA were studied. Results: Significant correlations between HR-pQCT and MRI parameters were found (p < 0.0001) and were strongest for Tb.N (r2 = 0.52), Ct.Th (r2 = 0.59), and site-specific Tb.Sp (r2 = 0.54,0.60). MRI and HR-pQCT provided statistically different values of structure parameters (p < 0.0001), with BV/TV and Tb.Th exhibiting the largest discrepancies (MR/HR-pQCT = 3,4). Although differences in the Tb.N values were statistically significant, the mean differences were on the order of our reproducibility measurements. Systematic differences between MRI and HR-pQCT analysis procedures leading to discrepancies in cortical thickness values were observed, with MRI values consistently higher. Minimal correlations were found between MRI or HR-pQCT parameters and DXA BMD or T-score, except between HR-pQCT measures at the radius and the ultradistal radius T-scores, where moderate correlations were found (r2 = 0.19,0.58). Conclusions: This study provides unique insight into two emerging noninvasive tools for bone structure evaluation. Our findings highlight the significant influence of analysis technique on results of in vivo assessment and underscore the importance of accounting for these differences when interpreting results from these modalities. [source] Neuroimaging and Neurologic Complications after Organ TransplantationJOURNAL OF NEUROIMAGING, Issue 2 2007ivkovi ABSTRACT Neurologic complications are common after transplantation and affect 30-60% of transplant recipients. The etiology of most of the posttransplant neurologic disorders is related to the opportunistic infections, both systemic and involving central nervous system (CNS), toxicity of immunosuppressive medications, and the metabolic insult created by the underlying primary disease and the transplant procedure. Neuroimaging studies are one of the key tools in the evaluation and enable early diagnosis of neurologic complications in transplant patients, especially posterior reversible leukoencephalopathy syndrome, central pontine myelinolysis, intracerebral hemorrhage, and fungal and bacterial abscesses. Magnetic resonance imaging (MRI) is the preferred technique, but each of the available neuroimaging techniques offers a unique insight into the pathophysiologic mechanisms underlying neurologic complications of transplantation. The role of neuroimaging in this population includes early detection of calcineurin inhibitor neurotoxicity, opportunistic infections, neoplasia, metabolic disorders, or cerebrovascular diseases. In addition, we can monitor longitudinal progression of disease and treatment response. [source] COMPARISON OF THE VIRGIN OLIVE OILS PRODUCED IN DIFFERENT REGIONS OF TURKEYJOURNAL OF SENSORY STUDIES, Issue 3 2009MUSTAFA Ö ABSTRACT Virgin olive oils from different regions of Turkey were collected and analyzed. The total phenolics and antioxidant capacity of the samples ranged from 30.26 to 208.61 mg gallic acid/kg and 0.60 to 5.61 Trolox equivalents/kg, respectively. Free acidity (0.44,7.31% oleic acid), peroxide value (6.83,39.60 meq O2/kg), total volatiles (0.11,0.37%), viscosity (65.50,85.40 cP), K232 value (1.30,2.54), K270 value (0.08,0.30), refractive index (1.470) and descriptive sensory properties of the samples were also measured. The multidimensional scaling (MDS) analysis indicated that positive and negative attributes classification of the olive oil sensory defining terms were mostly the case, and total phenolics content by itself may be a useful classification index. Also, MDS maps showed that the samples from Southeastern and Aegean regions are closer, while others are separate from each other. PRACTICAL APPLICATIONS Data for the physicochemical and sensory descriptive properties of virgin olive oils from Turkey are provided for the scientific community, olive oil consumers and traders. Also, utilization of sensory data by multidimensional scaling technique for geographical origin groupings provides a unique insight for researchers for similar objectives. In addition, some findings (i.e., the eligibility of phenolics content by itself for olive oil classification) of this article produce new results for fast and practical application purposes yet confirmed by other researchers. [source] Local structure of liquid and solid silver halides probed by XAFSJOURNAL OF SYNCHROTRON RADIATION, Issue 2 2001Andrea Di Cicco Investigation of the local structure of the high-temperature liquid and solid phases in the 300-725 K range of AgBr has been performed using the x-ray absorption spectroscopy (XAS). Structural results are compared with existing diffraction studies and computer simulations demonstrating the reliability of the XAS technique in determining the short-range structure. Present results on solid AgBr are in agreement with known thermal expansion data. The short-range g(r) of liquid AgBr is reconstructed showing the unique insight provided by the XAS technique in measuring short-range atom-atom correlations in liquids. [source] The oldest reptile in amber: a 120 million year old lizard from LebanonJOURNAL OF ZOOLOGY, Issue 1 2002E. N. Arnold Abstract Animals enclosed in amber often provide a unique insight into their surface structure. Such fossils of reptiles are rare and usually not extremely ancient, the earliest being no more than 40 million years (my). A recently discovered 120 my lizard from the Lower Cretaceous of Lebanon provides direct evidence that several common external features of autarchoglossan lizards had evolved by this time. Ecomorphology indicates that the lizard concerned had considerable climbing ability on open surfaces and perhaps in vegetation, and probably lived in a mesic forested environment, something supported by associated plant and invertebrate remains. [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] Post-starburst,active galactic nucleus connection: spatially resolved spectroscopy of H,-strong active galactic nucleiMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2006Tomotsugu Goto ABSTRACT Ever since the coexistence of an active galactic nucleus (AGN) and a starburst was observationally discovered, there has been a significant controversy over whether there is a physical connection between starbursts and AGN. If yes, it is a subject of interest to reveal which one triggers another. Here, we bring a unique insight into the subject by identifying 840 galaxies with both a post-starburst signature (strong Balmer absorption lines) and an AGN (based on the emission-line ratio). These post-starburst AGN account for the 4.2 per cent of all the galaxies in a volume-limited sample. The presence of a post-starburst phase with an active AGN itself is of importance, suggesting that AGN may outlive starbursts in the starburst,AGN connection. In addition, we have performed spatially resolved spectroscopy of three of our post-starbusrst AGN galaxies, obtaining some evidence that the post-starburst region is more extended, but sharply centred around the central AGN, confirming a spatial connection between the post-starburst and AGN. [source] External K+ modulates the activity of the Arabidopsis potassium channel SKOR via an unusual mechanismTHE PLANT JOURNAL, Issue 2 2006Ingela Johansson Summary Plant outward-rectifying K+ channels mediate K+ efflux from guard cells during stomatal closure and from root cells into the xylem for root,shoot allocation of potassium (K). Intriguingly, the gating of these channels depends on the extracellular K+ concentration, although the ions carrying the current are derived from inside the cell. This K+ dependence confers a sensitivity to the extracellular K+ concentration ([K+]) that ensures that the channels mediate K+ efflux only, regardless of the [K+] prevailing outside. We investigated the mechanism of K+ -dependent gating of the K+ channel SKOR of Arabidopsis by site-directed mutagenesis. Mutations affecting the intrinsic K+ dependence of gating were found to cluster in the pore and within the sixth transmembrane helix (S6), identifying an ,S6 gating domain' deep within the membrane. Mapping the SKOR sequence to the crystal structure of the voltage-dependent K+ channel KvAP from Aeropyrum pernix suggested interaction between the S6 gating domain and the base of the pore helix, a prediction supported by mutations at this site. These results offer a unique insight into the molecular basis for a physiologically important K+ -sensory process in plants. [source] A new map of mangroves for Kakadu National Park, Northern Australia, based on stereo aerial photographyAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 5 2007Anthea L. Mitchell Abstract 1.Using colour aerial photography, a set of fine (,1 m) spatial resolution orthomosaics and accompanying Digital Elevation Models (DEMs) were generated for the majority of mangroves in Kakadu National Park, Northern Australia, from which their extent and canopy height have been mapped. 2.The orthomosaics and DEMs, which were based on 68 stereo pairs acquired in 1991, cover an area of approximately 742 km2 and a coastal distance of 86 km. The DEMs have a height resolution of approximately ± 1 m. 3.The entire mosaic represents a key historical baseline data set of the extent and height of mangroves within the Park against which to observe and quantify changes in response to, for example, sea-level rise. 4.The data sets will be available to assist management of the coastal environment and also to provide a unique insight into the distribution, dynamics and condition of mangroves. The techniques used are applicable to mangroves and other forested wetlands in other regions of Australia and elsewhere. Copyright © 2007 John Wiley & Sons, Ltd. [source] MAXXI, Rome: Zaha Hadid ArchitectsARCHITECTURAL DESIGN, Issue 3 2010Mark Garcia Abstract Mark Garcia, editor of The Diagrams in Architecture (John Wiley & Sons, 2010), one of the first significant accounts of the diagram in architectural design, provides a unique insight into the diagrammatic form of Zaha Hadid Architects' new MAXXI museum in Rome. Copyright © 2010 John Wiley & Sons, Ltd. [source] Carers' narratives: Finding dementia with Lewy bodies experiencesAUSTRALASIAN JOURNAL ON AGEING, Issue 4 2009Kathryn A Nicholson Carers' narratives provide a unique insight into the caring experience. From a human interest perspective they have appeal to the general population; however, they also target and are read by niche audiences , families striving to understand the challenges of the caring role. This article examines four carer narratives and their relevance to particular niche audiences; three classified from the information provided on their book covers as pertaining to Alzheimer's disease and one to Parkinson's disease. It explores the impact of care on the caregivers and reviews the promoted diagnoses in light of the current understanding of dementia with Lewy bodies. The author argues that the information provided in the titles, in good faith, may not reflect the content of the narratives and that three of these narratives may provide carers of people who have dementia with Lewy bodies with insights into the challenges that this disease presents. [source] Strength in numbers: High phenotypic variance in early Cambrian trilobites and its evolutionary implicationsBIOESSAYS, Issue 11 2007Nigel C. Hughes Analysis of the degree of intraspecific morphological polymorphism during the evolutionary history of trilobites using an informatic approach1 provides striking evidence of a long-suspected but previously unsubstantiated pattern: degrees of polymorphism are markedly higher in phylogenetically basal, stratigraphically early species. This unequivocal pattern prompts further exploration of the relationship between microevolutionary variance and macroevolutionary history. It demonstrates that the ,traditional' fossil record of skeletonized organisms can provide unique insight into questions of major evolutionary interest. BioEssays 29:1081,1084, 2007. © 2007 Wiley Periodicals, Inc. [source] Lowering of blood pressure during chronic suppression of central sympathetic outflow: Insight from computer simulationsCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 2 2010Radu Iliescu Summary 1. Chronic electrical stimulation of the carotid sinuses has provided unique insight into the mechanisms that cause sustained reductions in blood pressure during chronic suppression of central sympathetic outflow. 2. Because renal denervation does not abolish the sustained fall in arterial pressure in response to baroreflex activation, this observation has seemingly challenged the concept that the kidneys play a critical role in the long-term control of arterial pressure during chronic changes in sympathetic activity. The aim of the present study was to use computer simulations to provide a more comprehensive understanding of physiological mechanisms that mediate sustained reductions in arterial pressure during prolonged baroreflex-mediated suppression of central sympathetic outflow. 3. Physiological responses to baroreflex activation under different conditions were simulated by an established mathematical model of human physiology (QHP2008; see Supporting Information (Appendix S1) provided in the online version of this article and/or http://groups.google.com/group/modelingworkshop). The model closely reproduced empirical data, providing important validation of its accuracy. 4. The simulations indicated that baroreflex-mediated suppression of renal sympathetic nerve activity does chronically increase renal excretory function but that, in addition, hormonal and haemodynamic mechanisms also contribute to this natriuretic response. The contribution of these redundant natriuretic mechanisms to the chronic lowering of blood pressure is of increased importance when suppression of renal adrenergic activity is prevented, such as after renal denervation. Activation of these redundant natriuretic mechanisms occurs at the expense of excessive fluid retention. 5. More broadly, the present study illustrates the value of numerical simulations in elucidating physiological mechanisms that are not obvious intuitively and, in some cases, not readily testable in experimental studies. [source] From segment to somite: Segmentation to epithelialization analyzed within quantitative frameworksDEVELOPMENTAL DYNAMICS, Issue 6 2007Paul M. Kulesa Abstract One of the most visually striking patterns in the early developing embryo is somite segmentation. Somites form as repeated, periodic structures in pairs along nearly the entire caudal vertebrate axis. The morphological process involves short- and long-range signals that drive cell rearrangements and cell shaping to create discrete, epithelialized segments. Key to developing novel strategies to prevent somite birth defects that involve axial bone and skeletal muscle development is understanding how the molecular choreography is coordinated across multiple spatial scales and in a repeating temporal manner. Mathematical models have emerged as useful tools to integrate spatiotemporal data and simulate model mechanisms to provide unique insights into somite pattern formation. In this short review, we present two quantitative frameworks that address the morphogenesis from segment to somite and discuss recent data of segmentation and epithelialization. Developmental Dynamics 236:1392,1402, 2007. © 2007 Wiley-Liss, Inc. [source] Optical imaging of infants' neurocognitive development: Recent advances and perspectivesDEVELOPMENTAL NEUROBIOLOGY, Issue 6 2008Yasuyo Minagawa-Kawai Abstract Near-infrared spectroscopy (NIRS) provides a unique method of monitoring infant brain function by measuring the changes in the concentrations of oxygenated and deoxygenated hemoglobin. During the past 10 years, NIRS measurement of the developing brain has rapidly expanded. In this article, a brief discussion of the general principles of NIRS, including its technical advantages and limitations, is followed by a detailed review of the role played so far by NIRS in the study of infant perception and cognition, including language, and visual and auditory functions. Results have highlighted, in particular, the developmental changes of cerebral asymmetry associated with speech acquisition. Finally, suggestions for future studies of neurocognitive development using NIRS are presented. Although NIRS studies of the infant brain have yet to fulfill their potential, a review of the work done so far indicates that NIRS is likely to provide many unique insights in the field of developmental neuroscience. © 2008 Wiley Periodicals, Inc. Develop Neurobiol, 2008 [source] First record of the brachiopod Lingulella waptaensis with pedicle from the Middle Cambrian Burgess ShaleACTA ZOOLOGICA, Issue 2 2010Sandra Pettersson Stolk Abstract Pettersson Stolk, S., Holmer, L. E. and Caron, J -B. 2010. First record of the brachiopod Lingulella waptaensis with pedicle from the Middle Cambrian Burgess Shale. ,Acta Zoologica (Stockholm) 91: 150,162 The organophosphatic shells of linguloid brachiopods are a common component of normal Cambrian,Ordovician shelly assemblages. Preservation of linguloid soft-part anatomy, however, is extremely rare, and restricted to a few species in Lower Cambrian Konservat Lagerstätten. Such remarkable occurrences provide unique insights into the biology and ecology of early linguloids that are not available from the study of shells alone. Based on its shells, Lingulella waptaensis Walcott, was originally described in 1924 from the Middle Cambrian Burgess Shale but despite the widespread occurrence of soft-part preservation associated with fossils from the same levels, no preserved soft parts have been reported. Lingulella waptaensis is restudied herein based on 396 specimens collected by Royal Ontario Museum field parties from the Greater Phyllopod Bed (Walcott Quarry Shale Member, British Columbia). The new specimens, including three with exceptional preservation of the pedicle, were collected in situ in discrete obrution beds. Census counts show that L. waptaensis is rare but recurrent in the Greater Phyllopod Bed, suggesting that this species might have been generalist. The wrinkled pedicle protruded posteriorly between the valves, was composed of a central coelomic space, and was slender and flexible enough to be tightly folded, suggesting a thin chitinous cuticle and underlying muscular layers. The nearly circular shell and the long, slender and highly flexible pedicle suggest that L. waptaensis lived epifaunally, probably attached to the substrate. Vertical cross-sections of the shells show that L. waptaensis possessed a virgose secondary layer, which has previously only been known from Devonian to Recent members of the Family Lingulidae. [source] THE GRAVITY MODEL: AN ILLUSTRATION OF STRUCTURAL ESTIMATION AS CALIBRATIONECONOMIC INQUIRY, Issue 4 2008EDWARD J. BALISTRERI Dawkins, Srinivasan, and Whalley ("Calibration,"Handbook of Econometrics, 2001) propose that estimation is calibration. We illustrate their point by examining a leading econometric application in the study of international and interregional trade by Anderson and van Wincoop ("Gravity with Gravitas: A Solution to the Border Puzzle,"American Economic Review, 2003). We replicate the econometric process and show it to be a calibration of a general equilibrium model. Our approach offers unique insights into structural estimation, and we highlight the importance of traditional calibration considerations when one uses econometric techniques to calibrate a model for comparative policy analysis. (JEL F10, C13, C60) [source] Patterns in naevoid skin disease: development, disease and modellingEXPERIMENTAL DERMATOLOGY, Issue 3 2010Stephen J. Gilmore Please cite this paper as: Patterns in naevoid skin disease: development, disease and modelling. Experimental Dermatology 2010; 19: 240,245. Abstract:, The aetiology of pattern-formation in human naevoid skin disease remains unknown. However, it is likely that the majority of previously proposed mechanisms , those that simply rely on passive clonal trafficking in embryogenesis , are incomplete. A more comprehensive explanation for pattern-formation in naevi invokes the principle of self-organization. We define two types of patterning: anatomical and functional. Anatomical patterning is where the abnormal clone is limited to regions of pathologic skin, while functional patterning is where the abnormal clone and pathologic skin are spatially uncorrelated. From a theoretical perspective self-organized naevoid patterns may be either secondary to local interactions between normal and aberrant genotypes or due to the interaction between aberrant genotypes and the presence of normal embryonic patterning cues. The latter possibility suggests the critical observation and analysis of patterns in naevoid skin disease may lead to unique insights into key aspects of early human embryogenesis. [source] Gesture Gives a Hand to Language and Learning: Perspectives from Cognitive Neuroscience, Developmental Psychology and EducationLINGUISTICS & LANGUAGE COMPASS (ELECTRONIC), Issue 4 2008Spencer D. Kelly People of all ages, cultures and backgrounds gesture when they speak. These hand movements are so natural and pervasive that researchers across many fields , from linguistics to psychology to neuroscience , have claimed that the two modalities form an integrated system of meaning during language production and comprehension. This special relationship has implications for a variety of research and applied domains. Gestures may provide unique insights into language and cognitive development, and also help clinicians identify, understand and even treat developmental disorders in childhood. In addition, research in education suggests that teachers can use gesture to become even more effective in several fundamental aspects of their profession, including communication, assessment of student knowledge, and the ability to instill a profound understanding of abstract concepts in traditionally difficult domains such as language and mathematics. This work converging from multiple perspectives will push researchers and practitioners alike to view hand gestures in a new and constructive way. [source] Studying porous materials with krypton-83 NMR spectroscopyMAGNETIC RESONANCE IN CHEMISTRY, Issue S1 2007Zackary I. Cleveland Abstract This report is the first review of 83Kr nuclear magnetic resonance as a new and promising technique for exploring the surfaces of solid materials. In contrast to the spin I = 1/2 nucleus of 129Xe, 83Kr has a nuclear spin of I = 9/2 and therefore possesses a nuclear electric quadrupole moment. Interactions of the quadrupole moment with the electronic environment are modulated by surface adsorption processes and therefore affect the 83Kr relaxation rate and spectral lineshape. These effects are much more sensitive probes for surfaces than the 129Xe chemical shielding and provide unique insights into macroporous materials in which the 129Xe chemical shift is typically of little diagnostic value. The first part of this report reviews the effect of quadrupolar interactions on the 83Kr linewidth in zeolites and also the 83Kr chemical shift behavior that is distinct from that of its 129Xe cousin in some of these materials. The second part reviews hyperpolarized (hp) 83Kr NMR spectroscopy of macroporous materials in which the longitudinal relaxation is typically too slow to allow sufficient averaging of thermally polarized 83Kr NMR signals. The quadrupolar-driven T1 relaxation times of hp 83Kr in these materials are sensitive to surface chemistry, surface-to-volume ratios, coadsorption of other species on surfaces, and surface temperature. Thus, 83Kr T1 relaxation can provide information about surfaces and chemical processes in macroscopic pores and can generate surface-sensitive contrast in hp 83Kr MRI. Copyright © 2007 John Wiley & Sons, Ltd. [source] Phylogeography of Douglas-fir based on mitochondrial and chloroplast DNA sequences: testing hypotheses from the fossil recordMOLECULAR ECOLOGY, Issue 9 2010PAUL F. GUGGER Abstract The integration of fossil and molecular data can provide a synthetic understanding of the ecological and evolutionary history of an organism. We analysed range-wide maternally inherited mitochondrial DNA and paternally inherited chloroplast DNA sequence data with coalescent simulations and traditional population genetic methods to test hypotheses of population divergence generated from the fossil record of Douglas-fir (Pseudotsuga menziesii), an ecologically and economically important western North American conifer. Specifically, we tested (i) the hypothesis that the Pliocene orogeny of the Cascades and Sierra Nevada caused the divergence of coastal and Rocky Mountain Douglas-fir varieties; and (ii) the hypothesis that multiple glacial refugia existed on the coast and in the Rocky Mountains. We found that Douglas-fir varieties diverged about 2.11 Ma (4.37 Ma,755 ka), which could be consistent with a Pliocene divergence. Rocky Mountain Douglas-fir probably resided in three or more glacial refugia. More variable molecular markers would be required to detect the two coastal refugia suggested in the fossil record. Comparison of mitochondrial DNA and chloroplast DNA variation revealed that gene flow via pollen linked populations isolated from seed exchange. Postglacial colonization of Canada from coastal and Rocky Mountain refugia near the ice margin at the Last Glacial Maximum produced a wide hybrid zone among varieties that formed almost exclusively by pollen exchange and chloroplast DNA introgression, not seed exchange. Postglacial migration rates were 50,165 m/year, insufficient to track projected 21st century warming in some regions. Although fossil and genetic data largely agree, each provides unique insights. [source] Variation within and among species in gene expression: raw material for evolutionMOLECULAR ECOLOGY, Issue 5 2006ANDREW WHITEHEAD Abstract Heritable variation in regulatory or coding regions is the raw material for evolutionary processes. The advent of microarrays has recently promoted examination of the extent of variation in gene expression within and among taxa and examination of the evolutionary processes affecting variation. This review examines these issues. We find: (i) microarray-based measures of gene expression are precise given appropriate experimental design; (ii) there is large inter-individual variation, which is composed of a minor nongenetic component and a large heritable component; (iii) variation among populations and species appears to be affected primarily by neutral drift and stabilizing selection, and to a lesser degree by directional selection; and (iv) neutral evolutionary divergence in gene expression becomes nonlinear with greater divergence times due to functional constraint. Evolutionary analyses of gene expression reviewed here provide unique insights into partitioning of regulatory variation in nature. However, common limitations of these studies include the tendency to assume a linear relationship between expression divergence and species divergence, and failure to test explicit hypotheses that involve the ecological context of evolutionary divergence. [source] Domesticating Nietzsche: Toward a Genealogy of Elisabeth Förster-Nietzsche's ,Novellen-Eierchen'ORBIS LITERARUM, Issue 5 2002Karin Bauer This investigation of an untitled novella manuscript penned by Elisabeth Förster-Nietzsche aims to contextualize her writing as an attempt to domesticate Nietzsche and his philosophy. It is argued that the manuscript provides unique insights into Elisabeth Förster-Nietzsche's incestuous fantasies and conflicted stance toward marriage and motherhood. While explicitly promoting marriage and motherhood, the plot, paradoxically, depicts not a single positive, functioning marriage. Although it romanticizes marriages, the novella challenges the dominant construction of the alte Jungfer as a social, cultural, and sexual deviant and an economic burden to family and society. Thus, while the ideological pronouncements of the novella advocate marriage and motherhood, the novella subverts these pronouncements and develops alternative familial arrangements, such as marriage-like brother,sister relations and surrogate parenthood. However, the conservative banality of these alternative models indicates that the novella is motivated more by wishfulfillment in the realm of fantasy than by the desire to develop an emancipatory dimension. Ultimately, Förster-Nietzsche's novella confirms not only her lack of literary talent, but also the vast gap separating Förster-Nietzsche's petit-bourgeois consciousness from Nietzsche's yearning for the intellectual risk of the ever-elusive free spirits. [source] The solution structure of the Mg2+ form of soybean calmodulin isoform 4 reveals unique features of plant calmodulins in resting cellsPROTEIN SCIENCE, Issue 3 2010Hao Huang Abstract Soybean calmodulin isoform 4 (sCaM4) is a plant calcium-binding protein, regulating cellular responses to the second messenger Ca2+. We have found that the metal ion free (apo-) form of sCaM4 possesses a half unfolded structure, with the N-terminal domain unfolded and the C-terminal domain folded. This result was unexpected as the apo-forms of both soybean calmodulin isoform 1 (sCaM1) and mammalian CaM (mCaM) are fully folded. Because of the fact that free Mg2+ ions are always present at high concentrations in cells (0.5,2 mM), we suggest that Mg2+ should be bound to sCaM4 in nonactivated cells. CD studies revealed that in the presence of Mg2+ the initially unfolded N-terminal domain of sCaM4 folds into an ,-helix-rich structure, similar to the Ca2+ form. We have used the NMR backbone residual dipolar coupling restraints 1DNH, 1DC,H,, and 1DC,C, to determine the solution structure of the N-terminal domain of Mg2+ -sCaM4 (Mg2+ -sCaM4-NT). Compared with the known structure of Ca2+ -sCaM4, the structure of the Mg2+ -sCaM4-NT does not fully open the hydrophobic pocket, which was further confirmed by the use of the fluorescent probe ANS. Tryptophan fluorescence experiments were used to study the interactions between Mg2+ -sCaM4 and CaM-binding peptides derived from smooth muscle myosin light chain kinase and plant glutamate decarboxylase. These results suggest that Mg2+ -sCaM4 does not bind to Ca2+ -CaM target peptides and therefore is functionally similar to apo-mCaM. The Mg2+ - and apo-structures of the sCaM4-NT provide unique insights into the structure and function of some plant calmodulins in resting cells. [source] Bond catastrophes in rhodium complexes: experimental charge-density studies of [Rh(C7H8)(PtBu3)Cl] and [Rh(C7H8)(PCy3)Cl]ACTA CRYSTALLOGRAPHICA SECTION B, Issue 5 2010Hazel A. Sparkes Rhodium complexes have potential uses in both catalysis and promoting the cleavage of C,C bonds. In order to further our understanding of these species and their potential applications, it is vital to obtain insight into the bonding within the species, particularly the Rh,C interactions, and to this end experimental charge-density studies have been undertaken on the title complexes. High-resolution single-crystal datasets to sin,,/, = 1.06,Å,1 were obtained at 100,K and analysed using Bader's `Atoms in Molecules' (AIM) approach. The results of the studies have provided unique insights into the bonding involving rhodium and highlight the importance of undertaking such investigations for transition metal compounds. [source] | ||||||||||||||||||||||