1,842 research outputs found

    Work and heat probability distribution of an optically driven Brownian particle: Theory and experiments

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    We analyze the equations governing the evolution of distributions of the work and the heat exchanged with the environment by a manipulated stochastic system, by means of a compact and general derivation. We obtain explicit solutions for these equations for the case of a dragged Brownian particle in a harmonic potential. We successfully compare the resulting predictions with the outcomes of experiments, consisting in dragging a micron-sized colloidal particle through water with a laser trap

    Differences in Informal Alcohol Protective Behavior Strategies between Fraternity & Sorority Members

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    Institutional interventions and formal policies designed to reduce alcohol misuse among fraternity and sorority members have been largely unsuccessful. However, informal policies to address alcohol use concerns can also develop within this subculture. This qualitative multi-case phenomenological study examined the informal policies chapters adopt to reduce risks associated with drinking. Findings suggested considerable informal policy development, which varies between fraternities and sororities. Sorority groups implemented more protective behavior strategies for members’ safety, whereas fraternities often focus on monitoring outside groups. Implications for practice suggest a combination of risk and harm-reduction approaches that facilitate peer-led protective behavioral strategies

    Accidental falls in hospitalized children: an analysis of the vulnerabilities linked to the presence of caregivers

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    Introduction. This study stemmed from the data gathered by a research conducted by the coordinator of the Department of Healthcare Services and a group of nurses involved in a research on accidental falls in hospitalized children at the ?G. Gaslini? Children?s Hospital and Scientific Research Institute in Genoa, Italy. The first retrospective study evaluated the accidental falls in hospitalized children referred to the three-year period 2003- 2006, while the second perspective study, referred to the trimester March-May 2007, found that the main cause of falls in children was parent?s distraction. Methods. The method adopted in the first phase of our study was a proactive risk analysis (The Basics of Healthcare Failure Mode and Effect Analysis), identified in the first place by the VA National Centre for Patient Safety and applied to the ?Child and parent hospital admission process?. This proactive risk analysis has proven to be very effective in preventing the risk of accidental falls in hospitalized children through effective communication and educational interventions. The second phase of our study consisted of two Focus Groups for accidental traumatic events. Results. The analysis of the results of the study showed how effective communication is instrumental, not only to have a better awareness of the children and their parents during their stay in hospital, but also to implement educational sessions on prevention to reduce the risk of accidental traumatic events. Conclusions. The present study contributes to improve safety and the quality of care by motivating nurses to keep their attention high on falls in hospitalized children, by monitoring and the development of new risk assessment tools

    In vitro uptake studies of cell targeting agents and nanoparticles

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    Recent progress in synthetic chemistry has enabled the preparation of new highly-defined polymers that exhibit changes in their structure in response to environmental changes. These responsive nanomaterials may be desirable as carriers of drugs to deliver at the cellular and sub-cellular level. However, the endocytic pathways used by these nanoparticles to access cells must be defined. Carboxylated polystyrene beads (C-PB) of 50 and 100 nm size were chosen as ‘model’ nanomedicines and their route of uptake into cells characterised and compared to thermoresponsive PLGA-b-(PEGMA-co-PPGMA) and PLA-b-(DEGMA-co-OEGMA) block copolymers of 50-150 nm (‘candidate’ drug delivery systems) uptake. A number of protocols were optimised for endocytosis inhibition studies. Results reported that the inhibition of clathrin mediated endocytosis (CME) with chlorpromazine (CPZ) was cell- and time-dependent. After the maximal effect of the inhibitor, the endocytosis of human transferrin (Htf), a marker of CME, recovered up to uninhibited levels in 3T3 and HCT116 cells. Furthermore, high passage number and ageing of cells showed a resistance towards the inhibition of the uptake of Htf with CPZ. Both PLGA-b-(PEGMA-co-PPGMA) and PLA-co-(DEGMA-co-OEGMA) thermoresponsive block copolymers presented colloidal instability and aggregation that impeded further endocytic pathway internalization experiments. However, the results reported in this thesis question some of the interpretation in the literature of the susceptibility of cells to CPZ in the internalization of nanomaterials. New experimental settings for CPZ inhibition studies should be considered and protocols optimised in order to avoid incorrect and potentially misleading outcomes

    Correctional nursing in Liguria, Italy: examining the ethical challenges

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    Introduction: Correctional nursing can involve significant ethical difficulties. This study examined ethical challenges encountered by correctional nurses in the Italian region of Liguria. Empirical data were analyzed in relation to relevant ethical standards. The former involved a study of 75 nurses and managers in the Ligurian correctional system, while the latter involved an analysis of the Italian Code of Ethics for Nurses and related standards for correctional practice. Methods: Quantitative and qualitative methods were used for the empirical study. Questionnaires were administered to collect data on participants' characteristics and care settings. The Measure of Job Satisfaction (MJS) was also administered. Five focus groups were conducted. Results: Quantitative Data: Respondents identified factors that mostly impacted on recruitment and retention. Unfavourable factors included: structural, organizational, and relational factors. Favourable factors included: nursing consultation, continuing education activities, and peer support. MJS results were equal to 'unsatisfied'. Qualitative Data: five themes were identified through thematic analysis of focus group data: Health needs of incarcerated persons; Negotiation of the boundaries between care and custody; Job satisfaction related to nursing in a correctional setting; Barriers to providing good care; and Security needs. Ten categories of norms were identified in the Code as areas of ethical standards relevant for the empirical data. Conclusions: Our empirical findings demonstrate that these nursing standards can be systematically compromised in correctional settings. Nurses feel compelled to provide ethically-problematic nursing services, with situations of moral distress. This research informs the development of needed policy, educational, and practice changes for nurses in correctional settings

    In vitro uptake studies of cell targeting agents and nanoparticles

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    Recent progress in synthetic chemistry has enabled the preparation of new highly-defined polymers that exhibit changes in their structure in response to environmental changes. These responsive nanomaterials may be desirable as carriers of drugs to deliver at the cellular and sub-cellular level. However, the endocytic pathways used by these nanoparticles to access cells must be defined. Carboxylated polystyrene beads (C-PB) of 50 and 100 nm size were chosen as ‘model’ nanomedicines and their route of uptake into cells characterised and compared to thermoresponsive PLGA-b-(PEGMA-co-PPGMA) and PLA-b-(DEGMA-co-OEGMA) block copolymers of 50-150 nm (‘candidate’ drug delivery systems) uptake. A number of protocols were optimised for endocytosis inhibition studies. Results reported that the inhibition of clathrin mediated endocytosis (CME) with chlorpromazine (CPZ) was cell- and time-dependent. After the maximal effect of the inhibitor, the endocytosis of human transferrin (Htf), a marker of CME, recovered up to uninhibited levels in 3T3 and HCT116 cells. Furthermore, high passage number and ageing of cells showed a resistance towards the inhibition of the uptake of Htf with CPZ. Both PLGA-b-(PEGMA-co-PPGMA) and PLA-co-(DEGMA-co-OEGMA) thermoresponsive block copolymers presented colloidal instability and aggregation that impeded further endocytic pathway internalization experiments. However, the results reported in this thesis question some of the interpretation in the literature of the susceptibility of cells to CPZ in the internalization of nanomaterials. New experimental settings for CPZ inhibition studies should be considered and protocols optimised in order to avoid incorrect and potentially misleading outcomes

    Flood scenario spatio-temporal mapping via hydrological and hydrodynamic modelling and a remote sensing dataset: A case study of the Basento river (Southern Italy)

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    Today, hydrological and hydraulic modelling are essential tools for flood risk management, although these models are still affected by elements of uncertainty that needs to be reduced by optimizing their results. The present research aims to implement an operational mechanism on the Basento river basin in Southern Italy based on the cascading use of a physically based concentrated-parameter hydrological model for the estimation of flood hydrographs, and a two-dimensional hydraulic model for flood mapping. The calibration of the hydrological model uses physical information to reduce the initial range of the set parameter values, and an automated optimisation procedure based on a genetic algorithm to find optimal values of the model parameters by comparing simulated and observed data for the 2013 flood event. To calibrate the hydraulic model, a series of flood maps extracted from multi-temporal SAR images was used. In addition, validation of the hydrological and hydraulic models was carried out on March 2011 flood event. The results show the reliability of the models during both calibration and validation, with the hydrological model achieving a Nash-Sutcliffe Efficiency coefficient between 0.86 and 0.91, and the hydraulic model leading to results with an accuracy close to 70 %. Considering the significance of the results, the developed modelling chain was used to simulate future event scenarios for risk management assessment and could operate as an early warning system

    Magnetostructural transition and magnetocaloric effect in Ni55Mn20Ga25 single crystals

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    A first order transition from a paramagnetic-austenite phase to a ferromagnetic-martensite phase occurring in off-stoichiometry single crystals of Ni2MnGa at 313 K presents unique features due to the multifunctional character of the magnetic shape memory alloy. A remarkable magnetocaloric effect, associated with an entropy change up to ΔS≈−86 J kg−1 K−1 and an adiabatic temperature change ΔT≈2.2 K, accompanied by mechanical strain Δε⩾3% have been observed in samples subjected to changes of the applied magnetic field ΔH=4×106 A∕m (≈5 T). The effects of magnetic field, temperature, and stress on the entropy variationΔS are quantified and compared

    The Price of Palliative Care: Towards a Complete Accounting of Costs and Benefits

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    The costs and benefits of hospice and palliative care have recently received attention for many compelling reasons. First, the cost of medical care over a lifetime is largely expended near the end-of-life. The impending demographic bulge of aging baby boomers will only heighten concerns about costs. Second, hospice and palliative care have been offered as potential vehicles for reducing late-in-life spending. Third, palliative care has gained legitimacy as a distinct medical specialty, having as it does a characteristic philosophy, specialized skill sets, and specific service delivery needs. This philosophy of care is consistent with and, to some degree, builds on the philosophy of care that geriatrics also promotes. In this article, currently accepted standards for cost-benefit analysis of health care interventions are outlined, and a framework to evaluate palliative care within these standards is provided. Recent publications on the economic implications of palliative care are reviewed, which are only the ‘‘tip of the iceberg’’ of the potential costs and benefits. Using this framework, the authors offer guidelines for performing comprehensive cost-benefit analyses of palliative care and conclude that many of the issues beneath the surface may be substantial and deserving of closer scrutiny. Methods for gathering relevant cost-benefit information are detailed, along with potential obstacles to implementation. This approach is applicable to palliative care in general, including palliative care for elders

    The Price of Palliative Care: Towards a Complete Accounting of Costs and Benefits

    Get PDF
    The costs and benefits of hospice and palliative care have recently received attention for many compelling reasons. First, the cost of medical care over a lifetime is largely expended near the end-of-life. The impending demographic bulge of aging baby boomers will only heighten concerns about costs. Second, hospice and palliative care have been offered as potential vehicles for reducing late-in-life spending. Third, palliative care has gained legitimacy as a distinct medical specialty, having as it does a characteristic philosophy, specialized skill sets, and specific service delivery needs. This philosophy of care is consistent with and, to some degree, builds on the philosophy of care that geriatrics also promotes. In this article, currently accepted standards for cost-benefit analysis of health care interventions are outlined, and a framework to evaluate palliative care within these standards is provided. Recent publications on the economic implications of palliative care are reviewed, which are only the ‘‘tip of the iceberg’’ of the potential costs and benefits. Using this framework, the authors offer guidelines for performing comprehensive cost-benefit analyses of palliative care and conclude that many of the issues beneath the surface may be substantial and deserving of closer scrutiny. Methods for gathering relevant cost-benefit information are detailed, along with potential obstacles to implementation. This approach is applicable to palliative care in general, including palliative care for elders
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