1,842 research outputs found

    Cadmium accumulation and physiological response of sunflower plants to Cd during the vegetative growing cycle

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    The effects of soil Cd contamination on Cd accumulation and distribution, growth and physiological responses of sunflower plants were investigated. Plants were subject to six levels of soil contamination (from 2.5 to 15 mg Cd kg/soil) with an untreated control, from the emergence of the cotyledon leaves until the harvest, when plants were at the flower bud stage. An overall increase of Cd concentration was found in all tissues of the plants (roots, stem, young, mature and old leaves) by increasing the Cd contamination in the soil. Regardless of treatments, Cd concentration in roots always exceeded those in the aboveground dry matter with a low translocation from roots to shoots. At early stage of growth, Cd concentration in plants was higher than at the flower bud stage. Soil Cd contamination did not affect plant growth, relative water content and gas exchange parameters. Negative and significant correlation was only found between Cd concentration in the young leaves and chlorophyll concentration at the end of vegetative growing stage. Roots and old leaves are the main metal sinks suggesting a defense or tolerance mechanism of the plants to avoid toxic levels in physiologically most active apical tissues. These results should be tested in open field to verify the suitability of sunflower in the area of phytotechnologies

    Improving co-authorship network structures by combining multiple data sources: evidence from Italian academic statisticians

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    The aim of the present contribution is to merge bibliographic data for members of a bounded scientific community in order to derive a complete unified archive, with top-international and nationally oriented production, as a new basis to carry out network analysis on a unified co-authorship network. A two-step procedure is used to deal with the identification of duplicate records and the author name disambiguation. Specifically, for the second step we strongly drew inspiration from a well-established unsupervised disambiguation method proposed in the literature following a network-based approach and requiring a restricted set of record attributes. Evidences from Italian academic statisticians were provided by merging data from three bibliographic archives. Non-negligible differences were observed in network results in the comparison of disambiguated and not disambiguated data sets, especially in network measures at individual level

    Quality issues in co-authorship data of a national scientific community

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    A stream of research on co-authorship, used as a proxy of scholars’ collaborative behavior, focuses on members of a given scientific community defined at discipline and/or national basis for which co-authorship data have to be retrieved. Recent literature pointed out that international digital libraries provide partial coverage of the entire scholar scientific production as well as under-coverage of the scholars in the community. Bias in retrieving co-authorship data of the community of interest can affect network construction and network measures in several ways, providing a partial picture of the real collaboration in writing papers among scholars. In this contribution, we collected bibliographic records of Italian academic statisticians from an online platform (IRIS) available at most universities. Even if it guarantees a high coverage rate of our population and its scientific production, it is necessary to deal with some data quality issues. Thus, a web scraping procedure based on a semi-automatic tool to retrieve publication metadata, as well as data management tools to detect duplicate records and to reconcile authors, is proposed. As a result of our procedure, it emerged that collaboration is an active and increasing practice for Italian academic statisticians with some differences according to the gender, the academic ranking, and the university location of scholars. The heuristic procedure to accomplish data quality issues in the IRIS platform can represent a working case report to adapt to other bibliographic archives with similar characteristics

    Hydrogen sulfide as potential regulatory gasotransmitter in arthritic diseases

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    The social and economic impact of chronic inflammatory diseases, such as arthritis, explains the growing interest of the research in this field. The antioxidant and anti-inflammatory properties of the endogenous gasotransmitter hydrogen sulfide (H2S) were recently demonstrated in the context of different inflammatory diseases. In particular, H2S is able to suppress the production of pro-inflammatory mediations by lymphocytes and innate immunity cells. Considering these biological effects of H2S, a potential role in the treatment of inflammatory arthritis, such as rheumatoid arthritis (RA), can be postulated. However, despite the growing interest in H2S, more evidence is needed to understand the pathophysiology and the potential of H2S as a therapeutic agent. Within this review, we provide an overview on H2S biological effects, on its role in immune-mediated inflammatory diseases, on H2S releasing drugs, and on systems of tissue repair and regeneration that are currently under investigation for potential therapeutic applications in arthritic diseases

    Sleep and β-Amyloid deposition in alzheimer disease: insights on mechanisms and possible innovative treatments

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    The preclinical stage of AD is characterized by β-amyloid (Aβ) aggregation into amyloid plaques and tau phosphorylation and aggregation into neurofibrillary tangles. There is a consensus on the importance of sleep within this context: the bidirectional relationship between sleep and AD pathology is supported by growing evidence that proved that the occurrence of sleep changes starting from the preclinical stage of AD, many years before the onset of cognitive decline. Hence, we review the most recent studies on sleep disturbances related to Aβ and the effects of sleep deprivation on Aβ accumulation in animal and human models. We also discuss evidence on the role of sleep in clearing the brain of toxic metabolic by-products, with original findings of the clearance activity of the glymphatic system stimulated by sleep. Furthermore, starting from new recent advances about the relationship between slow-wave sleep (SWS) and Aβ burden, we review the results of recent electroencephalographic (EEG) studies in order to clarify the possible role of SWS component disruption as a novel mechanistic pathway through which Aβ pathology may contribute to cognitive decline and, conversely, the eventual useful role of SWS in facilitating Aβ clearance. Finally, we discuss some promising innovative, effective, low-risk, non-invasive interventions, although empirical evidence on the efficacy of sleep interventions in improving the course of AD is at the very beginning

    A supervisor perspective on mental illness in the South African workspace

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    DATA AVAILABILITY : Data for this article will be made available on the data repository of the University of Pretoria.ORIENTATION : Supervisors have a direct impact on the work experience and outcomes of subordinates living with mental illness; these employees often struggle with consistent employment. RESEARCH PURPOSE : The supervisory role in addressing mental health in the workplace has been explored in terms of the managerial dimension, but not in terms of the supervisor’s perceptions and understanding of mental health issues. This study set out to explore and describe supervisors’ perceptions of mental illness in the workplace with specific reference to depression, bipolar disorder and anxiety in the South African workplace. MOTIVATION FOR THE STUDY : If supervisors are not aware of the effect of their behaviour and perceptions, reasonable workplace accommodations cannot be successfully made. RESEARCH APPROACH/DESIGN AND METHOD : Data were collected by means of in-depth, semi-structured, face-to-face interviews with 26 junior, middle and senior managers and analysed by means of thematic analysis. MAIN FINDINGS : Organisations in South Africa may not be ready to deal with mental illness in the workplace with supervisors who agree that they are not equipped to deal with mental health issues and their views on mental illness related to common misconceptions and stigmas surrounding it. PRACTICAL/MANAGERIAL IMPLICATIONS : Knowledge about mental health conditions within the workplace can assist managers in more effectively recognising, comprehending and implementing people management strategies related to these conditions. CONTRIBUTION/VALUE-ADD : Owing to the misconceptions of managers, mental wellness in the workplace may not be effectively managed. Better awareness would benefit both managers and HR professionals.http://www.sajhrm.co.zahj2024Human Resource ManagementSDG-03:Good heatlh and well-beingSDG-08:Decent work and economic growt

    Characterization of a synthetic bacterial self-destruction device for programmed cell death and for recombinant proteins release

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    <p>Abstract</p> <p>Background</p> <p>Bacterial cell lysis is a widely studied mechanism that can be achieved through the intracellular expression of phage native lytic proteins. This mechanism can be exploited for programmed cell death and for gentle cell disruption to release recombinant proteins when <it>in vivo </it>secretion is not feasible. Several genetic parts for cell lysis have been developed and their quantitative characterization is an essential step to enable the engineering of synthetic lytic systems with predictable behavior.</p> <p>Results</p> <p>Here, a BioBrickâ„¢ lysis device present in the Registry of Standard Biological Parts has been quantitatively characterized. Its activity has been measured in <it>E. coli </it>by assembling the device under the control of a well characterized N-3-oxohexanoyl-L-homoserine lactone (HSL) -inducible promoter and the transfer function, lysis dynamics, protein release capability and genotypic and phenotypic stability of the device have been evaluated. Finally, its modularity was tested by assembling the device to a different inducible promoter, which can be triggered by heat induction.</p> <p>Conclusions</p> <p>The studied device is suitable for recombinant protein release as 96% of the total amount of the intracellular proteins was successfully released into the medium. Furthermore, it has been shown that the device can be assembled to different input devices to trigger cell lysis in response to a user-defined signal. For this reason, this lysis device can be a useful tool for the rational design and construction of complex synthetic biological systems composed by biological parts with known and well characterized function. Conversely, the onset of mutants makes this device unsuitable for the programmed cell death of a bacterial population.</p
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