149 research outputs found
Dissolution and phosphate-induced transformation of ZnO nanoparticles in synthetic saliva probed by AGNES without previous solid-liquid separation. Comparison with UF-ICP-MS
The variation over time of free Zn2+ ion concentration in stirred dispersions of ZnO nanoparticles (ZnO NPs) prepared in synthetic saliva at pH 6.80 and 37 degrees C was followed in situ (without solid liquid separation step) with the electroanalytical technique AGNES (Absence of Gradients and Nernstian Equilibrium Stripping). Under these conditions, ZnO NPs are chemically unstable due to their reaction with phosphates. The initial stage of transformation (around 5-10 h) involves the formation of a metastable solid (presumably ZnHPO4), which later evolves into the more stable hopeite phase. The overall decay rate of ZnO NPs is significantly reduced in comparison with phosphate-free background solutions of the same ionic strength and pH. The effective equilibrium solubilities of ZnO (0.29-0.47 mg.L-1), as well as conditional excess-ligand stability constants and fractional distributions of soluble Zn species, were determined in the absence and presence of organic components. The results were compared with the conventional ultrafiltration and inductively coupled plasma-mass spectrometry (UF-ICP-MS) methodology. AGNES proves to be advantageous in terms of speed, reproducibility, and access to speciation information. KeywordsThis work was supported by the Spanish Ministry MINECOunder Grant No. CTM2016-78798 and European UnionSeventh Framework Programme FP7-NMP.2012.1.3-3 underGrant No. 310584 (NANoREG). FQ gratefully acknowledgesa grant from AGAUR
Dynamics of trace metal sorption by an ion-exchange chelating resin described by a mixed intraparticle/film diffusion transport model. The Cd/Chelex case
The time-evolution of Cd2+ ion sorption by Chelex 100 resin was studied in batch experiments as a function of time, pH, ionic strength, stirring rate, mass of resin and initial metal ion concentration. In the experimental conditions, the amount of resin sites are in excess with respect to the amount of metal ion, leading to extensive depletion of metal in bulk solution when equilibrium is reached. The data were described using a mixed control mass transport model in finite volume conditions (MCM) that includes explicitly both intraparticle and film diffusion steps. Exact numerical computations and a new approximate analytical expression of this model are reported here. MCM successfully predicts the influence of pH and ionic strength on the experimental Cd(II)/Chelex kinetic profiles (which cannot be justified by a pure film diffusion controlled mechanism) with a minimum number of fitting parameters. The overall diffusion coefficient inside the resin was modelled in terms of the Donnan factor and the resin/cation binding stability constant. The values of the latter coefficient as a function of pH and ionic strength were estimated from the Gibbs-Donnan model. Even though MCM is numerically more involved than models exclusively restricted to film or intraparticle diffusion control, it proves to be accurate in a wider range of values of the mass transfer Biot number and solution/resin metal ratios.The authors gratefully acknowledge support for this research from the Spanish Ministry MINECO (Projects CTM2013-48967 and CTM2016-78798) and by the âComissionat d'Universitats i Recerca de la Generalitat de Catalunyaâ (2014SGR1132). FQ acknowledges a grant from AGAUR
On the Thermodynamic Bethe Ansatz Equation in Sinh-Gordon Model
Two implicit periodic structures in the solution of sinh-Gordon thermodynamic
Bethe ansatz equation are considered. The analytic structure of the solution as
a function of complex is studied to some extent both analytically and
numerically. The results make a hint how the CFT integrable structures can be
relevant in the sinh-Gordon and staircase models. More motivations are figured
out for subsequent studies of the massless sinh-Gordon (i.e. Liouville) TBA
equation.Comment: 32 pages, 18 figures, myart.st
Integrated Care for Chronic Diseases â State of the Art
Chronic diseases represent a high cost for healthcare systems, for individuals, families, businesses and governments. The World Health Organization (WHO) estimates that an increase of 10% of chronic diseases is associated with a reduction of 0.5% of annual economic growth. Primary care has proven to ensure high levels of efficiency, effectiveness, equity, safety, timely and centrality of the patient achieving better health outcomes and lower costs. The Chronic Care Model (CCM) proposes a proactive approach in assisting the empowerment of patients and their community. The CCM contributes to improving the quality of care and health outcomes and the reduction of inequalities (e.g., ethnicity, social status) too
Versatile Cross-Dehydrogenative Coupling of Heteroaromatics and Hydrogen Donors via Decatungstate Photocatalysis
A facile sunlight-induced derivatization of heteroaromatics via photocatalyzed C-H functionalization in amides, ethers, alkanes and aldehydes is described. Tetrabutylammonium decatungstate (TBADT) was used as the photocatalyst and allowed to carry out the process under mild conditions
DIGITAL TRANSITION STRATEGIES AND TRAINING PROGRAMS FOR DIGITAL CURATION OF MUSEUM
Small and medium-sized museums have been particularly impacted by the COVID-19 pandemic, as they often have limited resources and staff to manage the challenges posed by the pandemic. In order for them to survive during the pandemic but also embracing the extensive use of technology in our everyday lives, museums have to adapt to this new reality. The aim of the Museum-Next project is to provide small and medium-sized museums with a new generation of specialised EU professionals working in the Cultural Heritage sector, equipped with a recognised, cross-cutting and high-level digital skillset: the Digital Curators. In the digital age, museum digital curators play a critical role in preserving, organising, and presenting museum collections online. As part of the project, our research performed a desk analysis on the state of the art on museum digital transition strategies and museum digital curator training programs already implemented at EU scale in order to map good practices and tools already existing so as to highlight the current situation and the gaps that may appear in the topic
Acute kidney injury and acute kidney disease in high-dose cisplatin-treated head and neck cancer
Background: In locally advanced head and neck squamous cell carcinoma (LA-SCCHN) at least 200mg/m2 (standard dose 300 mg/m2) of cisplatin concomitant with radiotherapy represents the standard of care, both in postoperative and conservative settings. Nevertheless, high dose administration every 3 weeks is often replaced with low dose weekly cisplatin to avoid toxicities like kidney injury, though often failing to reach the therapeutic dose. Our aim was to investigate the incidence of renal impairment in the real-life setting, integrating high dose cisplatin with adequate supportive therapy, and to explore both Acute Kidney Injury (AKI) and Acute Kidney Disease (AKD), a recently described clinical renal syndrome that encompasses functional alterations of the kidney lasting fewer than 3 months. Methods: One hundred and nine consecutive patients affected by LA-SCCHN and treated with at least a cumulative dosage of 200 mg/m2 of cisplatin concomitant with radiotherapy were enrolled in this prospective observational study. Results: AKI was reported in 12.8% of patients, 50% of whom were stage 1 (KDIGO criteria), while 25.7% of the cohort developed AKD. Patients with baseline estimated Glomerular Filtration Rate (eGFR) < 90 ml/min showed a higher incidence of AKD (36.2% vs 17.7%). Hypertension, baseline eGFR, and therapy with Renin-angiotensin-aldosterone system inhibitors proved to be significant factors associated with both AKI and AKD. Conclusion: AKI and AKD are not rare complications of high-dose cisplatin, but an appropriate prevention strategy and accurate monitoring of patients during treatment could lead to a reduction of the burden of these conditions
Moisture Status of the Skin of the Feet Assessed by the Visual Test Neuropad Correlates With Foot Ulceration in Diabetes
How a Clinical Trial Unit can improve independent clinical research in rare tumors: the Italian Sarcoma Group experience
Background: The Italian Sarcoma Group (ISG) is a nonprofit group of professionals established in 1997 aimed to improve the quality of care and promote the independent research in sarcomas. The increased regulatory requirements, the chance to increase the number of trials with other cooperative groups and an interest from pharmaceutical companies in supporting independent research, generated the need of an internal service for research management.
Methods and results: In 2010, ISG implemented in its organization a Clinical Trial Unit (CTU). The CTU was appointed to fully manage Clinical Trial Operations, to guarantee regulation compliance and provide a central support to the investigators, fostering a collaboration both at national and international level. In 2016 ISG promoted 25 studies in about 120 centers, with a fivefold increase in the last 5 years: 68% were interventional and 32% observational. Nine of the 17 interventional studies (52%) were supported by pharmaceutical companies, while 4 (24%) were funded by European Commission within specific projects on sarcomas and 4 (24%) were supported by the ISG itself.
Conclusion: The contribution of ISG researchers to the international community was striking from the earliest years of the ISG creation. The challenges of the regulatory clinical research scenario, which imposes solid and hard-fast methodology with deep knowledge and expertise, highlighted the need to identify qualified and dedicated experts able to run and follow the multifaceted aspects of trials. Our analysis demonstrated how this model has led to a growth in competitiveness of the group. The collaboration between clinicians and CTU made possible to support the research with high scientific and ethical standards and to increase the number of trials, sites and overall enrolled patients. The reduced time for approvals, the continuous support to sites, the increased speed in data collection and analysis make the ISG research attractive for pharmaceutical industries, despite the problems that have characterized the independent research in the last years. The ability to fully manage and oversight Clinical Operations and the high quality of delivered services, have led the ISG to be recognized as a reliable partner and coordinator within the international sarcoma networks
- âŠ