287 research outputs found

    Distance dependence of force and dissipation in non-contact atomic force microscopy on Cu(100) and Al(111)

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    The dynamic characteristics of a tip oscillating in the nc-AFM mode in close vicinity to a Cu(100)-surface are investigated by means of phase variation experiments in the constant amplitude mode. The change of the quality factor upon approaching the surface deduced from both frequency shift and excitation versus phase curves yield to consistent values. The optimum phase is found to be independent of distance. The dependence of the quality factor on distance is related to 'true' damping, because artefacts related to phase misadjustment can be excluded. The experimental results, as well as on-resonance measurements at different bias voltages on an Al(111) surface, are compared to Joule dissipation and to a model of dissipation in which long-range forces lead to viscoelastic deformations

    A stochastic approach for assessing the chronic environmental risk generated by wet-weather events from integrated urban wastewater systems

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    Wet-weather discharges from urban areas with a combined wastewater system represent a threat for surface waters. In fact, when the system capacity is reached during medium/big rain events, a mixture of stormwater and untreated wastewater is discharged through combined sewer overflows (CSOs) or bypass (BP) of wastewater treatment plants (WWTP). The discharged pollutant loads are highly variable in time and space, making it difficult to correctly monitor and assess the environmental risks for a specific catchment. The present work proposes a methodology to assess the chronic impact of wet-weather discharges from integrated urban wastewater systems (IUWS) by using a stochastic approach. Monitoring data from the literature were used to characterize the discharges and to predict the risk posed by (micro-)pollutants on a yearly basis in an archetype IUWS. Calculated risks from wet-weather discharges are compared against those posed by WWTP effluent. The results show that CSOs pose a higher risk to surface waters compared to WWTP effluent and bypass, with polycyclic aromatic hydrocarbons being the category of micropollutants of major concern for CSOs. Conversely, WWTP effluent discharges are responsible for most of the risk associated with pharmaceuticals. A sensitivity and uncertainty analysis highlighted the importance of performing an accurate estimation of the recipient flow rate, which can provide a better risk estimation than focusing only on the characterization of the discharged concentrations. In climate change scenarios, where recipient flow rate reduction and overflow volume increment is expected, the risk caused by wet-weather discharges may increase for all micropollutant categories, including pharmaceuticals.Environmental chronic risk generated by wet-weather discharges compared to final effluent was stochastically assessed, also from a climate-change perspective, stressing their growing contribution for many (micro-)pollutants

    Assessing the contribution of wet-weather discharges on micropollutants release by urban catchments

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    Wet-weather discharges from integrated urban wastewater systems (IUWS) represent a threat for surface waters. When the system capacity is reached during medium/large rain events, a mixture of stormwater and untreated wastewater is discharged to surface water through Combined Sewer Overflows (CSOs) or Bypass (BP) of Wastewater Treatment Plants (WWTP). The loads of contaminants discharged by CSOs and BP are highly variable in time and space (Petrie, 2021), making it difficult to correctly monitor and assess the environmental risk for a specific catchment. The present work aims at assessing the impact of 12 micropollutants present in wet-weather discharges on receiving surface water, by using an archetype IUWS, defined through a stochastic approach. Monitoring data from literature were retrieved and elaborated to characterize the discharges and to predict the risk posed by micropollutants on a yearly horizon. The calculated risk from wet- weather discharges was compared against that posed by WWTP effluent (EFF)

    BRAF and MEK Inhibitors and Their Toxicities: A Meta-Analysis

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    Purpose: This meta-analysis summarizes the incidence of treatment-related adverse events (AE) of BRAFi and MEKi. Methods: A systematic search of Medline/PubMed was conducted to identify suitable articles published in English up to 31 December 2021. The primary outcomes were profiles for all-grade and grade 3 or higher treatment-related AEs, and the analysis of single side effects belonging to both categories. Results: The overall incidence of treatment-related all-grade Aes was 99% for Encorafenib (95% CI: 0.97–1.00) and 97% for Trametinib (95% CI: 0.92–0.99; I2 = 66%) and Binimetinib (95% CI: 0.94–0.99; I2 = 0%). In combined therapies, the rate was 98% for both Vemurafenib + Cobimetinib (95% CI: 0.96–0.99; I2 = 77%) and Encorafenib + Binimetinib (95% CI: 0.96–1.00). Grade 3 or higher adverse events were reported in 69% of cases for Binimetinib (95% CI: 0.50–0.84; I2 = 71%), 68% for Encorafenib (95% CI: 0.61–0.74), and 72% for Vemurafenib + Cobimetinib (95% CI: 0.65–0.79; I2 = 84%). The most common grade 1–2 AEs were pyrexia (43%) and fatigue (28%) for Dabrafenib + Trametinib and diarrhea for both Vemurafenib + Cobimetinib (52%) and Encorafenib + Binimetinib (34%). The most common AEs of grade 3 or higher were pyrexia, rash, and hypertension for Dabrafenib + Trametinib (6%), rash and hypertension for Encorafenib + Binimetinib (6%), and increased AST and ALT for Vemurafenib + Cobimetinib (10%). Conclusions: Our study provides comprehensive data on treatment-related adverse events of BRAFi and MEKi combination therapies, showing related toxicity profiles to offer a helpful tool for clinicians in the choice of therapy

    An integrated modelling framework to assess cascade water reuse in urban areas

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    In the recent years water scarcity has been an increasing problem for many countries worldwide. For this reason, there is currently a strong focus on increasing reclaimed wastewater reuse, especially for agriculture purposes (Fernandes and Cunha Marques, 2023). Besides, the cost of energy from conventional resources is increasing, thus the energy sector is moving towards more distributed and efficient use of heat sources across urban areas. Typical applications are heat pumps using local groundwater reservoirs and subsequently discharging in the nearby surface water bodies/artificial channels (recipients). Furthermore, for a better quality of these recipients and for a better performance of wastewater treatment plants (WWTP), stormwater can be collected in separated sewers discharging only the urban runoff to the recipient. In this context, water is subjected to multiple uses, with potential cross-contaminations across different compartments, posing a risk for the environment. Hence, there is a strong need for tools capable of supporting stakeholders towards a wiser and safer use of water resources, to ensure long-term resilience, stability, sustainability and security of the society with regard to water use. An integrated model was developed to simulate the fate and associated risk of hazardous contaminants in a cascade water reuse system
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