1,626 research outputs found

    A review of governmental management accounting : research around the turn of the century

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    This paper shows that governmental management accounting research around the turn of the century, as published in FAM, MAR and EAR, is different from general management accounting research in some respects. Although there are variations related to topics, theories and research methods, a mainstream in governmental management accounting research seems to exist. Research is predominantly directed to the way in which technical management accounting innovations are used, including organizational and contextual factors that might influence the use of these new techniques. Qualitatively oriented case and field studies are the dominant research methods, and the research is inspired by various theoretical viewpoints, e.g. economics, organization theory and neo-institutional theory. NPM, regarded as a lower level economic theory, turns out to be highly influential. The paper gives recommendations for governmental management accounting research in the future: more attention has to be paid to quantitative research, impact studies on NPM must be promoted, and jointly conducted research projects by management accounting and public administration researchers are welcomed.

    Factors influencing peak expiratory flow in teenage boys

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    Background. Peak expiratory flow (PEF) is a useful measure of pulmonary health status and is frequently utilised in asthm, management. Reduction in PEF is usually indicative of OIlS( of asthma symptoms. However, use can be made of PEF values only if normal values are known. The definition of normal range is always difficult and may vary between regions and be affected by a variety of factors.Objective. To establish PEF values for teenage boys in a Cape Town suburb and examine factors that possibly influence this measurement.Setting. A high school for boys in the southern suburbs of Cape Town.Methods. Measurements of PEF were taken for 124 boys. Subjects were approximately 16 years old and apparently healthy at the time of survey. Further details were provid by means of a questionnaire.Results. PEF ranged from 350 to 760 1/min, with a mean (± standard deviation (SD» of 539 ± 681/min. Factors expected to influence PEF included height and mass, where is unexpected factors included sport intensity and academic grade. A trend to reduced peak flow was already evident in boys who smoked and boys from homes where a parent smoked. Regression analysis suggested peak flow differenct.s in our population compared with the standard reference.Conclusion. Interpretation of results obtained from peak-flow instruments should take into account additional knowledge concerning the individual. Further surveys of the South African population and of different groups should be done to establish local standards and factors influencing PE

    Application of regulatory sequence analysis and metabolic network analysis to the interpretation of gene expression data

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    We present two complementary approaches for the interpretation of clusters of co-regulated genes, such as those obtained from DNA chips and related methods. Starting from a cluster of genes with similar expression profiles, two basic questions can be asked: 1. Which mechanism is responsible for the coordinated transcriptional response of the genes? This question is approached by extracting motifs that are shared between the upstream sequences of these genes. The motifs extracted are putative cis-acting regulatory elements. 2. What is the physiological meaning for the cell to express together these genes? One way to answer the question is to search for potential metabolic pathways that could be catalyzed by the products of the genes. This can be done by selecting the genes from the cluster that code for enzymes, and trying to assemble the catalyzed reactions to form metabolic pathways. We present tools to answer these two questions, and we illustrate their use with selected examples in the yeast Saccharomyces cerevisiae. The tools are available on the web (http://ucmb.ulb.ac.be/bioinformatics/rsa-tools/; http://www.ebi.ac.uk/research/pfbp/; http://www.soi.city.ac.uk/~msch/)

    Embodied learning at a distance: From sensory-motor experience to constructing and understanding a sine graph

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    Educational technologies develop quickly. Which functions of face-to-face education can be substituted by technology for distance learning? One of the risks of online education is the lack of embodied interactions. We investigate what embodied interactive technologies might offer for teaching trigonometry when learning at a distance. In a multiple case study, we analyze the potential of embodied action-based design for fostering conceptual understanding of a sine graph. It appears that independent learning with tablet-based activities leads to acquiring new sensory-motor coordinations. Some students include these new embodied experiences into mathematical discourse and trigonometry problem solving themselves, while others still need some support from a teacher. However, distantly acquired embodied experiences can be easily recalled in a few days after learning and serve well as a substrate for further conceptualization and problem-solving. The results speak for a clear contribution that embodied design might provide for grounding conceptual understanding in distance learning. However, we expect embodied design to be particularly helpful in a blended learning format

    Infrared spectroscopy of jet-cooled neutral and ionized aniline-Ar

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    We report the infrared (IR) absorption spectrum of the jet-cooled neutral aniline–Ar Van der Waals complex together with that of the aniline–Ar cation in the 350–1700 cm−1 range. The spectra are measured using mass-selective ion detection in two different IR–ultraviolet double-resonance excitation schemes, using a free-electron laser as a source of widely tunable, intense IR radiation. A comparison with calculated IR spectra of the bare neutral aniline and of the cation of aniline allows for an unambiguous assignment of all the observed modes. The dissociation limit of the neutral aniline–Ar complex is bracketed between 273 and 329 cm−1, significantly lower than previously estimated. <br

    A study on the structure and vibrations of diphenylamine by resonance-enhanced multiphoton ionization spectroscopy and ab initio calculations

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    Laser‐desorption jet‐cooling has been applied in combination with mass‐selective gas‐phase spectroscopic techniques to study the structure and low‐frequency vibrations of diphenylamine (DPA). Two‐color (1+1â€Č) resonance‐enhanced multiphoton ionization has been used to measure the vibrationally resolved excitation spectrum of the S1←S0 transition in the 305–309 nm region. Ion‐dip measurements have been performed to determine the vibrational structure in the electronic ground state. The electronic spectra of DPA are dominated by long progressions in low‐frequency vibrations involving the motion of the phenyl rings as a whole. For the interpretation of the experimental data ab initio calculations have been performed at the Hartree–Fock level for the S0‐state and using single‐excitation configuration interaction for the S1‐state. The DPA molecule is found to change from a pyramidal geometry around the N‐atom with unequal torsional angles of the phenyl groups in the S0‐state to a planar geometry with equal torsional angles in the S1‐state. The two most prominent vibrational motions are the in‐phase wagging and the in‐phase torsion of the phenyl rings. In addition, the resonance‐enhanced multiphoton ionization spectra of the S1←S0 transition in the DPA‐Ar, DPA‐Kr, and DPA‐Xe van der Waals complexes have been measured. From these spectra it is inferred that there is a coupling between the van der Waals modes and the low‐frequency intra‐molecular modes of DPA

    Analyzing the higher order structure of proteins with conformer-selective ultraviolet photodissociation

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    The top-down approach in protein sequencing requires simple methods in which the analyte can be readily dissociated at every position along the backbone. In this context, ultraviolet photodissociation (UVPD) recently emerged as a promising tool because, in contrast to slow heating techniques such as collision induced dissociation (CID), the absorption of UV light is followed by a rather statistically distributed cleavage of backbone bonds. As a result, nearly complete sequence coverage can be obtained. It is well-known, however, that gas-phase proteins can adopt a variety of different, sometimes coexisting conformations and the influence of this structural diversity on the UVPD fragmentation behavior is not clear. Using ion mobility-UVPD-mass spectrometry we recently showed that UVPD is sensitive to the higher order structure of gas-phase proteins. In particular, the cis/trans isomerization of certain proline peptide bonds was shown to significantly influence the UVPD fragmentation pattern of two extended conformers of 11+ ubiquitin. Building on these results, we here provide conformer-selective UVPD data for 7+ ubiquitin ions, which are known to be present in a much more diverse and wider ensemble of different structures, ranging from very compact to highly extended species. Our data show that certain conformers fall into groups with similar UVPD fragmentation pattern. Surprisingly, however, the conformers within each group can differ tremendously in their collision cross section. This indicates that the multiple coexisting conformations typically observed for 7+ ubiquitin are caused by a few, not easily inter-convertible, subpopulations

    Photoexcitation of mass/charge selected heminâș, caught in helium nanodroplets

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    We report on a method by which mass/charge selected ions are picked up from a linear ion trap by liquid helium droplets. The size distributions of the doped droplets are measured via acceleration experiments. Depending on the source temperature, droplet sizes ranging from tens of thousands to several million helium atoms are obtained. Droplets doped with hemin, an iron containing porphyrin molecule, in the charge state +1 are then investigated using laser spectroscopy. It is observed that excitation with UV/VIS light can lead to ejection of the ion from the droplet. For doped droplets with a median size of B150 000 helium atoms, the absorption of two photons at 380 nm is needed for ejection to become efficient. When droplets become smaller, the ejection efficiency is observed to strongly increase. Monitoring the ejection yield as a function of excitation wavelength can be used to obtain the optical spectrum of heminâș. Compared to the spectrum of free gas-phase heminâș at room temperature, the narrower and shifted to the blue
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