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Related Techniques (relate + techniques)
Selected AbstractsGraphic and movie illustrations of human prenatal development and their application to embryological education based on the human embryo specimens in the Kyoto collectionDEVELOPMENTAL DYNAMICS, Issue 2 2006Shigehito Yamada Abstract Morphogenesis in the developing embryo takes place in three dimensions, and in addition, the dimension of time is another important factor in development. Therefore, the presentation of sequential morphological changes occurring in the embryo (4D visualization) is essential for understanding the complex morphogenetic events and the underlying mechanisms. Until recently, 3D visualization of embryonic structures was possible only by reconstruction from serial histological sections, which was tedious and time-consuming. During the past two decades, 3D imaging techniques have made significant advances thanks to the progress in imaging and computer technologies, computer graphics, and other related techniques. Such novel tools have enabled precise visualization of the 3D topology of embryonic structures and to demonstrate spatiotemporal 4D sequences of organogenesis. Here, we describe a project in which staged human embryos are imaged by the magnetic resonance (MR) microscope, and 3D images of embryos and their organs at each developmental stage were reconstructed based on the MR data, with the aid of computer graphics techniques. On the basis of the 3D models of staged human embryos, we constructed a data set of 3D images of human embryos and made movies to illustrate the sequential process of human morphogenesis. Furthermore, a computer-based self-learning program of human embryology is being developed for educational purposes, using the photographs, histological sections, MR images, and 3D models of staged human embryos. Developmental Dynamics 235:468,477, 2006. © 2005 Wiley-Liss, Inc. [source] Empirical orthogonal functions and related techniques in atmospheric science: A reviewINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 9 2007A. Hannachi Abstract Climate and weather constitute a typical example where high dimensional and complex phenomena meet. The atmospheric system is the result of highly complex interactions between many degrees of freedom or modes. In order to gain insight in understanding the dynamical/physical behaviour involved it is useful to attempt to understand their interactions in terms of a much smaller number of prominent modes of variability. This has led to the development by atmospheric researchers of methods that give a space display and a time display of large space-time atmospheric data. Empirical orthogonal functions (EOFs) were first used in meteorology in the late 1940s. The method, which decomposes a space-time field into spatial patterns and associated time indices, contributed much in advancing our knowledge of the atmosphere. However, since the atmosphere contains all sorts of features, e.g. stationary and propagating, EOFs are unable to provide a full picture. For example, EOFs tend, in general, to be difficult to interpret because of their geometric properties, such as their global feature, and their orthogonality in space and time. To obtain more localised features, modifications, e.g. rotated EOFs (REOFs), have been introduced. At the same time, because these methods cannot deal with propagating features, since they only use spatial correlation of the field, it was necessary to use both spatial and time information in order to identify such features. Extended and complex EOFs were introduced to serve that purpose. Because of the importance of EOFs and closely related methods in atmospheric science, and because the existing reviews of the subject are slightly out of date, there seems to be a need to update our knowledge by including new developments that could not be presented in previous reviews. This review proposes to achieve precisely this goal. The basic theory of the main types of EOFs is reviewed, and a wide range of applications using various data sets are also provided. Copyright © 2007 Royal Meteorological Society [source] Approaches for Quantifying the Metabolism of Physical Economies: A Comparative Survey: Part II: Review of Individual ApproachesJOURNAL OF INDUSTRIAL ECOLOGY, Issue 1 2002Peter L. Daniels Summary This article is the second of a two-part series that describes and compares the essential features of nine "physical economy" approaches for mapping and quantifying the material demands of the human economy upon the natural environ-ment. These approaches are critical tools in the design and implementation of industrial ecology strategies for greater eco-efficiency and reduced environmental impacts of human economic activity. Part I of the series provided an overview, meth-odological classification, and comparison of a selected set of major materials flow analysis (MFA) and related techniques. This sequel includes a convenient reference and overview of the major metabolism measurement approaches in the form of a more detailed summary of the key specific analytical and other features of the approaches introduced in part I. The surveyed physical economy related environmental analysis ap-proaches include total material requirement and output mod-els, bulk MFA (IFF (Department of Social Ecology, Institute for Interdiscplinary Studies of Austrian Universities) material flow balance model variant), physical input-output tables, substance flow analysis, ecological footprint analysis, environmental space, material intensity per unit service, life-cycle assessment (LCA), the sustainable process index, and company-level MFA. [source] Raman spectroscopy and related techniques: state of the art and future directions in Italy,JOURNAL OF RAMAN SPECTROSCOPY, Issue 2 2008Giuseppe Compagnini Abstract The 20th Italian Conference on Raman Spectroscopy and non-linear effects was held in Catania in June 2007. I had the pleasure to chair the Conference in which scientists from different countries shared their research activities, started new collaborations and straightened the existing ones. For the first time in the GNSR history, the contributors were invited to present papers suitable to be collected in a Special Issue of a peer-reviewed journal and the Journal of Raman Spectroscopy has been chosen for its long tradition on Raman spectroscopy and related fields. This Special Issue is dedicated to the memory of Giorgio Mattei who recently passed away. It includes 28 contributions reporting results and new ideas on material science, biochemistry, astrophysics and science of cultural heritage. Copyright © 2008 John Wiley & Sons, Ltd. [source] Preface to the second special issue on non-linear Raman spectroscopy and related techniquesJOURNAL OF RAMAN SPECTROSCOPY, Issue 12 2003Peter Radi Guest Editor No abstract is available for this article. [source] Musings about the development of XAFSJOURNAL OF SYNCHROTRON RADIATION, Issue 2 2001Edward A. Stern A personal recollection of the development of X-ray absorption fine structure (XAFS) into a structure-determination technique is presented. Because of confusion in the theoretical explanation of the `Kronig structure', now called EXAFS, the extended XAFS, its explanation remained unresolved for about 40 years. As I was introduced to the EXAFS phenomenon by Farrel Lytle and saw his impressive data, the thought came to me that scattering of the photoelectron from surrounding atoms could be the mechanism of the effect. My graduate student, Dale Sayers, agreed to work on developing the theory under my supervision and to make EXAFS measurements under Lytle's supervision as his PhD thesis. The theory led to the idea of a Fourier transform of the EXAFS, which showed peaks from surrounding atoms, proving the validity of the theory and suggesting the method of structure determination by using standards from known structures. Within a few years, facilities at synchrotron sources were developed to measure XAFS, opening up the technique to the general scientific community. In spite of some initial growing pains, XAFS has matured into a powerful technique for local structure and has been applied to obtain magnetic structure, in addition to distribution of atoms. Other related techniques have been spawned from XAFS, expanding the impact of the original phenomenon. [source] Application of microscopy in authentication of traditional Tibetan medicinal plant Halenia ellipticaMICROSCOPY RESEARCH AND TECHNIQUE, Issue 1 2008Jie Li Abstract Halenia elliptica D. Don, a popularly used ethnodrug from Qinghai-Tibetan plateau, was studied to reveal the indispensable morphoanatomic details. The fixed, sectioned, and stained plant materials as well as the epidermis, powder, and maceration materials were studied using light microscope according to the usual microscopic techniques. The results of the microscopic features were systematic described and illustrated. In the root, an endodermal cell was divided into 8-16-22 and 38-50-62 daughter cells in transverse section and in face view, respectively, and 9-11-13 phloem strands were present in primary structure; in the stem, stone cells were observed in the cortex, pericycle, and external phloem while 17-19-21 internal phloem strands were present in an incontinuous ring; in the pedicel, 8-10-12 internal phloem strands were observed to form an incontinuous ring; anisocytic and anomocytic stomata were present in leaf and sepal epidermis; pollen grain was with three germinal apertures and furrows; a few tracheids, a large number of spiral vessels, and various fibers were observed. Also, semiquantitative and quantitative micrographic parameter tables were simultaneously presented. Further, the key authentication parameters were concluded. The study indicated that light microscopy and related techniques could be unambiguously applied to the authentication of Halenia elliptica. Microsc. Res. Tech., 2008. © 2007 Wiley-Liss, Inc. [source] A unified mathematical framework for the measurement of richness and evenness within and among multiple communitiesOIKOS, Issue 2 2004Thomas D. Olszewski Biodiversity can be divided into two aspects: richness (the number of species or other taxa in a community or sample) and evenness (a measure of the distribution of relative abundances of different taxa in a community or sample). Sample richness is typically evaluated using rarefaction, which normalizes for sample size. Evenness is typically summarized in a single value. It is shown here that Hurlbert's probability of interspecific encounter (,1), a commonly used sample-size independent measure of evenness, equals the slope of the steepest part of the rising limb of a rarefaction curve. This means that rarefaction curves provide information on both aspects of diversity. In addition, regional diversity (gamma) can be broken down into the diversity within local communities (alpha) and differences in taxonomic composition among local communities (beta). Beta richness is expressed by the difference between the composite rarefaction curve of all samples in a region with the collector's curve for the same samples. The differences of the initial slopes of these two curves reflect the beta evenness thanks to the relationship between rarefaction and ,1. This relationship can be further extended to help interpret species-area curves (SAC's). As previous authors have described, rarefaction provides the null hypothesis of passive sampling for SAC's, which can be interpreted as regional collector's curves. This allows evaluation of richness and evenness at local and regional scales using a single family of well-established, mathematically related techniques. [source] An Integrative Approach for Treating Postherpetic Neuralgia,A Case ReportPAIN PRACTICE, Issue 3 2007Shu-Ming Wang MD Abstract: This report describes the successful treatment of a patient with postherpetic neuralgia using traditional pharmacology in combination with acupuncture. Case Report: A 13-year-old girl developed postherpetic neuralgia following a severe attack of varicella zoster. Despite a 1-week course of intravenous acyclovir initiated at the onset of symptoms, the patient developed persistent left facial pain and constant nausea after lesions were healed. A comprehensive pain treatment regimen, consisting of a stellate ganglia block, medications, transcutaneous electrical nerve stimulation and hypnosis, was administered, but the patient did not gain any incremental pain relief. The acupuncture service was consulted to provide assistance with this patient's pain management. A combination of body and auricular acupuncture as well as related techniques, including acupressure and transcutaneous acupoint electrical stimulation, was added to the pain treatment regimen. After 10 complementary acupuncture treatments over a 2-month period, the patient's nausea disappeared. Her left facial pain continued to decline from a maximum of 10 to 0 as assessed by a visual analog scale over a period of 4 months following self-administered treatments of acupressure and transcutaneous acupoint electrical stimulation. The patient was then gradually weaned off all her medications and the complementary acupuncture treatment. She was discharged from the pediatric pain clinic after 5 months of the combined therapy. Conclusions: Acupuncture and its related techniques may be an effective adjunctive treatment for symptoms associated with postherpetic neuralgia and deserve further study. [source] Electron microscopy of InGaN nanopillars spontaneously grown on Si(111) substratesPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 5 2010Th. Kehagias Abstract The mopholological, structural and chemical properties of InxGa1,xN nanopillars directly grown on Si (111) substrates, by molecular beam epitaxy, were investigated employing transmission electron microscopy related techniques. Single crystalline, single phase nanopillars were observed exhibiting a low density of crystal defects, which contribute to good crystal quality. Initial nanostructures merge through subgrain boundaries to form final nanopillars. Energy dispersive X-ray analysis revealed a very low InN mole fraction near the interface with the substrate, owing to high desorption rates from the elevated growth temperature, and gradually higher In incorporation rates near the tips of the nanopillars. This compositional fluctuation is maintained due to poor segregation of indium adatoms along the c-axis of the nanopillars towards the Si interface. A second species of long and narrow nanopillars was found In-free. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Natural oxidation of InN quantum dots: the role of cubic InNPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 1 2010David González Abstract The natural aging process occured in indium nitride quantum dots (QDs) heterostructures as a consequence of exposure to the atmosphere has been studied by means of transmission electron microscopy and electron beam related techniques. The comparison between GaN-capped and uncapped InN QDs kept at room conditions during 36 months indicates the structural changes that take place. While the capping layer seems to act in a protective way avoiding any change in the QDs, the uncapped structures suffer a series of phase transformations, where the original wurtzite structure is replaced by a layer of cubic phases. The main constituent of this layer is shown to be bcc-In2O3 formed by the substitution of the nitrogen atoms by oxygen from the atmosphere. This supposes a transformation from a hexagonal to a cubic structure, explained by the existence of an oxygen-rich cubic InN acting as an intermediate phase. The difference in the formation enthalpy between the original and the final product, together with the good match between the crystals would explain this transformation that shows the high instability of InN at environmental conditions. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Sampling subproblems of heterogeneous Max-Cut problems and approximation algorithms,RANDOM STRUCTURES AND ALGORITHMS, Issue 3 2008Petros Drineas Abstract Recent work in the analysis of randomized approximation algorithms for NP -hard optimization problems has involved approximating the solution to a problem by the solution of a related subproblem of constant size, where the subproblem is constructed by sampling elements of the original problem uniformly at random. In light of interest in problems with a heterogeneous structure, for which uniform sampling might be expected to yield suboptimal results, we investigate the use of nonuniform sampling probabilities. We develop and analyze an algorithm which uses a novel sampling method to obtain improved bounds for approximating the Max-Cut of a graph. In particular, we show that by judicious choice of sampling probabilities one can obtain error bounds that are superior to the ones obtained by uniform sampling, both for unweighted and weighted versions of Max-Cut. Of at least as much interest as the results we derive are the techniques we use. The first technique is a method to compute a compressed approximate decomposition of a matrix as the product of three smaller matrices, each of which has several appealing properties. The second technique is a method to approximate the feasibility or infeasibility of a large linear program by checking the feasibility or infeasibility of a nonuniformly randomly chosen subprogram of the original linear program. We expect that these and related techniques will prove fruitful for the future development of randomized approximation algorithms for problems whose input instances contain heterogeneities. © 2007 Wiley Periodicals, Inc. Random Struct. Alg., 2008 [source] Positron Imaging Studies of Rotating DrumsTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 1 2005David J. Parker Abstract The potential of the radioisotope tracer technique of positron emission tomography (PET) and the related techniques of positron emission projection imaging (PEPI) and positron emission particle tracking (PEPT) is illustrated with reference to laboratory scale studies of particulate motion in rotating drums, operating either in batch or continuous flow modes. Sand grains, glass beads and TiO2 granules down to 0.5mm diameter were labelled. Using PEPT the transition between rolling and slumping modes has been identified and the velocity profile within the active layer has been determined for a range of drum diameters. PEPI has been used to measure and explain residence time distributions, while all three techniques have been used to study segregation based on particle size, both radially and axially within the drum. Data on particle motion within a novel baffled drum is also presented. Le potentiel de la technique de traçage par radio-isotopes en tomographie par émission de positrons (PET) et les techniques associées de l'imagerie par projection des émissions de positrons (PEPI) ou le traçage des particules par émission de positrons (PEPT), est illustré en référence à des études à l'échelle de laboratoire du déplacement de particules dans des tambours rotatifs, fonctionnant soit en mode d'écoulement discontinu ou continu. Des grains de sable, des billes de verre et des granules de TiO2 aussi petits que 0,5 mm de diamètre ont été marqués. À l'aide de la technique PEPT, la transition entre les modes roulant et glissant a été identifiée et le profil de vitesse à l'intérieur de la couche active a été déterminé pour une gamme de diamètres de tambours. La technique PEPI a été utilisée pour mesurer et expliquer les distributions de temps de séjour, tandis que les trois techniques ont servi pour l'analyse de la ségrégation d'après la taille des particules, à la fois radialement et axialement dans le tambour. Des données sur le déplacement des particules dans un nouveau tambour à chicanes sont également présentées. [source] Financial Champions and Masters of Innovation: Analyzing the Effects of Balancing Strategic Orientations,THE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 6 2009Angela Paladino Theory predicts that market and resource orientations can each lead to innovation and financial success. Despite this, no research has examined whether the pursuit of both resource and market orientations is feasible and, if so, the impact of this combined effect on innovative and financial outcomes. This paper aims to address these gaps. Thus, it is the first to examine the interdependent relationship between market orientation (MO) and resource orientation (RO). Additionally, this study responds to calls for (1) cross-disciplinary research, particularly in the areas of marketing and strategic management, and (2) comparative studies of diverse strategic orientations on performance. In doing so, this paper investigates the difference in innovation performance and financial performance between firms adopting a high or low degree of market orientation or a high or low degree of resource orientation. This allows us to observe independent and interdependent effects of these orientations on the firm's performance. Data were collected from 250 senior executives in Australia. Confirmatory factor analysis and related techniques were applied to assess the robustness of the measures used. A two-way between-groups analysis of variance (ANOVA) was used to evaluate the relationships. Results show the emergence of four organizational types: unfocused imitators or followers; market-driven innovators; masters of innovation; and financial champions. From these, financial champions emerge as having the greatest impact on the financial performance of the firm, while masters of innovation are best for maximizing innovation outcomes. In fact, organizations with a high RO in the matrix (masters of innovation and financial champions) achieved a higher impact on innovation relative to the quadrants reflecting a lower MO. Results also demonstrate that pursuing a low degree of resource and market orientations leads to inferior financial performance. Therefore, a balance of resource and market orientations is important. A potential extension of this research is to assess these relationships on an industry-by-industry basis. This would contribute to our knowledge by allowing us to determine if and how these results differ between industries. Managerial and theoretical implications are also discussed. [source] Review fluorescence correlation spectroscopy for probing the kinetics and mechanisms of DNA hairpin formationBIOPOLYMERS, Issue 1 2008Alan Van Orden Abstract This article reviews the application of fluorescence correlation spectroscopy (FCS) and related techniques to the study of nucleic acid hairpin conformational fluctuations in free aqueous solutions. Complimentary results obtained using laser-induced temperature jump spectroscopy, single-molecule fluorescence spectroscopy, optical trapping, and biophysical theory are also discussed. The studies cited reveal that DNA and RNA hairpin folding occurs by way of a complicated reaction mechanism involving long- and short-lived reaction intermediates. Reactions occurring on the subnanoseconds to seconds time scale have been observed, pointing out the need for experimental techniques capable of probing a broad range of reaction times in the study of such complex, multistate reactions. © 2007 Wiley Periodicals, Inc. Biopolymers 89: 1,16, 2008. This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] Newly qualified teachers' learning related to their use of information and communication technology: a Swedish perspectiveBRITISH JOURNAL OF EDUCATIONAL TECHNOLOGY, Issue 5 2006Sven B. Andersson This qualitative study focuses on newly qualified teachers' use of information and communication technology (ICT) as a tool for meeting the challenges of their everyday work. The overarching aim is to investigate whether they can contribute to new knowledge about learning in ICT contexts. Theoretical points of departure concern the changeable nature of learning in situations where ways of communicating knowledge and skills are changed. The study draws upon interviews and observations. The findings show intersections picturing the new technique as partly changing the circumstances for teaching, learning and collaboration between colleagues. The new teachers' utterances show that ICT utilisation is extensive and exhibits great variation both among female and among male participants. Boundary-crossing changes become visible in the collaboration between more experienced teachers and those who are newly qualified, especially when they work on a common development project. However, there are relatively few teachers who bring up active ICT use in connection with pupils' learning. Changed roles because of ICT competence raise questions about the importance of systematic ICT features within teacher education. Many of the newly qualified teachers wish they had more knowledge about ICT and related techniques. Another question is whether newly qualified teachers who show interest in using the technique can take on the role as agents of change in their active and creative use of ICT. [source] | |||||||||||||||||||