3,859 research outputs found

    Software for full-color 3D reconstruction of the biological tissues internal structure

    Full text link
    A software for processing sets of full-color images of biological tissue histological sections is developed. We used histological sections obtained by the method of high-precision layer-by-layer grinding of frozen biological tissues. The software allows restoring the image of the tissue for an arbitrary cross-section of the tissue sample. Thus, our method is designed to create a full-color 3D reconstruction of the biological tissue structure. The resolution of 3D reconstruction is determined by the quality of the initial histological sections. The newly developed technology available to us provides a resolution of up to 5 - 10 {\mu}m in three dimensions.Comment: 11 pages, 8 figure

    Colossal magnetocapacitance and scale-invariant dielectric response in phase-separated manganites

    Full text link
    Thin films of strongly-correlated electron materials (SCEM) are often grown epitaxially on planar substrates and typically have anisotropic properties that are usually not captured by edge-mounted four-terminal electrical measurements, which are primarily sensitive to in-plane conduction paths. Accordingly, the correlated interactions in the out-of-plane (perpendicular) direction cannot be measured but only inferred. We address this shortcoming and show here an experimental technique in which the SCEM under study, in our case a 600 Angstrom-thick (La1-yPry)0.67Ca0.33MnO3 (LPCMO) film, serves as the base electrode in a metal-insulator-metal (MIM) trilayer capacitor structure. This unconventional arrangement allows for simultaneous determination of colossal magnetoresistance (CMR) associated with dc transport parallel to the film substrate and colossal magnetocapacitance (CMC) associated with ac transport in the perpendicular direction. We distinguish two distinct strain-related direction-dependent insulator-metal (IM) transitions and use Cole-Cole plots to establish a heretofore unobserved collapse of the dielectric response onto a universal scale-invariant power-law dependence over a large range of frequency, temperature and magnetic field.Comment: 32 pages, 4 figures, Supplementary section included, Submitted to Nature Physic

    ‘Content to be sad’ or ‘runaway apprentice’? The psychological contract and career agency of young scientists in the entrepreneurial university

    Get PDF
    This article examines employee agency in psychological contracts by exploring how young scientists proactively shape their careers in response to unmet expectations induced by academic entrepreneurialism. It uses the lens of social exchange to examine their relationships with the professors engaged in two types of activities: collaborative research characterized by diffuse/reciprocal exchange, and commercial ventures, by restricted/negotiated exchange. These two categories show how career agency varies in orientation, form and behavioural outcome depending on the relational context within which their psychological contracts evolve. Those involved in collaborative research experienced a relational psychological contract and responded to unfulfilled career promises by ‘extended investment’ in their current jobs. They use ‘proxy agency’ by enlisting the support of their professors. However, some become ‘trapped’ in perennial temporary employment and are ‘content to be sad’. By contrast, those involved in research commercialization experienced a transactional contract and assert ‘personal agency’ by crafting their own entrepreneurial careers. They are ‘runaways’ who seek autonomy. The evidence is based on interviews with 24 doctoral/postdoctoral researchers and 16 professors from three leading UK universities. The study extends psychological contract theory by incorporating career agency and sheds new light on changing academic careers

    Asymmetric intergroup bullying: the enactment and maintenance of societal inequality at work

    Get PDF
    What does inequality mean for dysfunctional organizational behaviours, such as workplace bullying? This article argues that workplace bullying can be understood as a manifestation of intergroup dynamics originating beyond the organization. We introduce the construct of asymmetric intergroup bullying: the disproportionate mistreatment of members of low status groups, with the intended effect of enhancing the subordination of that group in society at large. Analysis of data from 38 interviews with public and private sector workers in Turkey depicts a pattern of asymmetric intergroup bullying, undertaken to achieve organizational and broader sociopolitical goals. Respondents reported bullying acts used to get rid of unwanted personnel, with the goal of avoiding severance pay, or of removing supporters of the former government from positions of political and economic influence. Bullying was also described as working towards the dominance of the sociocultural worldview of one political group over another. We discuss asymmetric intergroup bullying as one mechanism through which acute intergroup hierarchy in the broader society corrupts management practice and employee interactions, in turn exacerbating economic inequality along group lines

    Is informed consent related to success in exercise and diet intervention as evaluated at 12 months? DR's EXTRA study

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>There is a permanent need to evaluate and develop the ethical quality of scientific research and to widen knowledge about the effects of ethical issues. Therefore we evaluated whether informed consent is related to implementation and success in a lifestyle intervention study with older research participants. There is little empirical research into this topic.</p> <p>Methods</p> <p>The subjects (n = 597) are a subgroup of a random population sample of 1410 men and women aged 57-78 years who are participating in a 4-year randomized controlled intervention trial on the effects of physical exercise and diet on atherosclerosis, endothelial function and cognition. Data were collected in two steps: A questionnaire about informed consent was given to all willing participants (n = 1324) three months after the randomization. Data on implementation and success in the exercise and diet interventions were evaluated at 12 months by intervention-group personnel. The main purpose of the analysis procedure performed in this study was to identify and examine potential correlates for the chosen dependent variables and to generate future hypotheses for testing and confirming the independent determinants for implementation and success. The nature of the analysis protocol is exploratory at this stage.</p> <p>Results</p> <p>About half of the participants (54%) had achieved good results in the intervention. Nearly half of the participants (47%) had added to or improved their own activity in some sector of exercise or diet. Significant associations were found between performance in the interventions and participants' knowledge of the purpose of the study (p < 0.001), and between success in interventions and working status (p = 0.02), and the participants' knowledge of the purpose of the study (p = 0.04).</p> <p>Conclusion</p> <p>The main finding of this study was that those participants who were most aware or had understood the purpose of the study at an early stage had also attained better results at their 12-month intervention evaluation. Therefore, implementation and success in intervention is related to whether subjects receive a sufficient amount and are able to comprehend the information provided i.e. the core principles of informed consent.</p> <p>Trial Registration</p> <p>(ISRCTN 45977199)</p

    Control of intestinal stem cell function and proliferation by mitochondrial pyruvate metabolism.

    Get PDF
    Most differentiated cells convert glucose to pyruvate in the cytosol through glycolysis, followed by pyruvate oxidation in the mitochondria. These processes are linked by the mitochondrial pyruvate carrier (MPC), which is required for efficient mitochondrial pyruvate uptake. In contrast, proliferative cells, including many cancer and stem cells, perform glycolysis robustly but limit fractional mitochondrial pyruvate oxidation. We sought to understand the role this transition from glycolysis to pyruvate oxidation plays in stem cell maintenance and differentiation. Loss of the MPC in Lgr5-EGFP-positive stem cells, or treatment of intestinal organoids with an MPC inhibitor, increases proliferation and expands the stem cell compartment. Similarly, genetic deletion of the MPC in Drosophila intestinal stem cells also increases proliferation, whereas MPC overexpression suppresses stem cell proliferation. These data demonstrate that limiting mitochondrial pyruvate metabolism is necessary and sufficient to maintain the proliferation of intestinal stem cells

    The Role of Individual Variables, Organizational Variables and Moral Intensity Dimensions in Libyan Management Accountants’ Ethical Decision Making

    Get PDF
    This study investigates the association of a broad set of variables with the ethical decision making of management accountants in Libya. Adopting a cross-sectional methodology, a questionnaire including four different ethical scenarios was used to gather data from 229 participants. For each scenario, ethical decision making was examined in terms of the recognition, judgment and intention stages of Rest’s model. A significant relationship was found between ethical recognition and ethical judgment and also between ethical judgment and ethical intention, but ethical recognition did not significantly predict ethical intention—thus providing support for Rest’s model. Organizational variables, age and educational level yielded few significant results. The lack of significance for codes of ethics might reflect their relative lack of development in Libya, in which case Libyan companies should pay attention to their content and how they are supported, especially in the light of the under-development of the accounting profession in Libya. Few significant results were also found for gender, but where they were found, males showed more ethical characteristics than females. This unusual result reinforces the dangers of gender stereotyping in business. Personal moral philosophy and moral intensity dimensions were generally found to be significant predictors of the three stages of ethical decision making studied. One implication of this is to give more attention to ethics in accounting education, making the connections between accounting practice and (in Libya) Islam. Overall, this study not only adds to the available empirical evidence on factors affecting ethical decision making, notably examining three stages of Rest’s model, but also offers rare insights into the ethical views of practising management accountants and provides a benchmark for future studies of ethical decision making in Muslim majority countries and other parts of the developing world

    Efficiency analysis of spur gears with a shifting profile

    Get PDF
    A model for the assessment of the energy efficiency of spur gears is presented in this study, which considers a shifting profile under different operating conditions (40–600 Nm and 1500–6000 rpm). Three factors affect the power losses resulting from friction forces in a lubricated spur gear pair, namely, the friction coefficient, sliding velocity and load sharing ratio. Friction forces were implemented using a Coulomb’s model with a constant friction coefficient which is the well-known Niemann formulation. Three different scenarios were developed to assess the effect of the shifting profile on the efficiency under different operating conditions. The first kept the exterior radii constant, the second maintained the theoretical contact ratio whilst in the third the exterior radii is defined by the shifting coefficient. The numerical results were compared with a traditional approach to assess the results.The authors would like to acknowledge Project DPI2013-44860 funded by the Spanish Ministry of Science and Technology and the COST ACTION TU 1105 for supporting this research
    • …
    corecore