The issue of contamination by synthetic resins in radiocarbon dating: the case of a painting by Ambrogio Lorenzetti

Abstract Nowadays, the most common products used in restoration are of synthetic origin. Being these resins obtained from fossil oil, they are devoid of 14C. Therefore, a not complete removal from the sample to be dated can be the cause of a consistent apparent ageing of the dated artworks. A chemical pre-treatment is required in order to clean the samples before the measurements. At INFN-LABEC laboratory in Florence, a new procedure based on the use of an extraction with chloroform as solvent was tested. In this paper, the radiocarbon measurements made on a restored polyptyc by Ambrogio Lorenzetti are presented

Digital Technologies for Community Engagement in Decision-Making and Planning Process

The way that we describe and understand cities is radically transforming—just like the tools we use for designing and implementing them. The change is often seen only as a technological aspect, for example, in the concept of smart cities. Smart cities are believed to provide societies with a higher quality of life thanks to modern technologies. However, there is also a human factor that is needed to make these changes go smoothly: acceptance. For many, change and innovation cause fear and disrupt everyday habits. Public participation is crucial both for understanding citizens’ needs and for adopting new programs. The ability to try, engage, or entertain with new technologies will move innovation from the abstract level to the level of understanding. A smart city can be a living laboratory that tests new technologies and services where citizens and urban communities are active actors in the process. Innovation can be used by the city to improve its services, mutual communication, and engage citizens in its activities and projects, co-creating urban space and city strategy through new participatory tools. Trends in European cities show that the use of modern digital technologies and interactive tools can be used to involve citizens in urban decision-making processes, e.g., when creating or revitalizing public spaces. Modern participatory technologies that enable citizens to explore, analyze, design, and evaluate spatial information on the basis of shared and open data that bring new challenges and new opportunities to cities, as well as for citizens. Our knowledge of the use of these new technologies, however, is still narrow and limited today. In the following research, the authors intend to explore the potential of digital technologies for community engagement in the decision-making process in smart cities by examining the specific settings upon which social innovation builds

Learning in an Agile Setting: A Multilevel Study on the Evolution of Organizational Routines

Recognizing a serious lack of research on routinized individual actions and organizational adaptation in the stability-change paradox, we intend to provide an in-depth explanation of the way in which agile methods affect organizational learning in self-managed, team-based organizations, taking a multi-level evolutionary approach. We explore learning in agile organizations by breaking the analysis of organizational routines down into different levels \u2013 individual, team and organization \u2013 and describing the process of variation, selection and retention of routines at each level. Leveraging on multiple case studies, we discuss how team members learn and gain knowledge, from both direct and indirect experience, and analyze how teams develop conceptual frameworks and interpret those experiences. Finally, we discuss how organizational memory develops and how teams in agile organizations adapt simultaneously within an ecological structure that also comprises the changing environment. Our findings reveal substantial flaws in the capacity of agile methods to foster organizational learning

Antiviral and antioxidant activity of a hydroalcoholic extract from Humulus lupulus L.

A hydroalcoholic extract from female inflorescences of Humulus lupulus L. (HOP extract) was evaluated for its anti-influenza activity. The ability of the extract to interfere with different phases of viral replication was assessed, as well as its effect on the intracellular redox state, being unbalanced versus the oxidative state in infected cells. The radical scavenging power, inhibition of lipoperoxidation, and ferric reducing activity were assayed as antioxidant mechanisms. A phytochemical characterization of the extract was also performed. We found that HOP extract significantly inhibited replication of various viral strains, at different time from infection. Viral replication was partly inhibited when virus was incubated with extract before infection, suggesting a direct effect on the virions. Since HOP extract was able to restore the reducing conditions of infected cells, by increasing glutathione content, its antiviral activity might be also due to an interference with redox-sensitive pathways required for viral replication. Accordingly, the extract exerted radical scavenging and reducing effects and inhibited lipoperoxidation and the tBOOH-induced cytotoxicity. At phytochemical analysis, different phenolics were identified, which altogether might contribute to HOP antiviral effect. In conclusion, our results highlighted anti-influenza and antioxidant properties of HOP extract, which encourage further in vivo studies to evaluate its possible application

Mediación docente en el desarrollo de la comprensión lectora en un entorno virtual de tercer ciclo de primaria de una Institución privada de Lima

La mediación docente para el desarrollo de la comprensión lectora es un tema lleno de matices en educación y, debido a ello, este ha sido investigado con anterioridad en contextos regulares. No obstante, la COVID 19 movilizó esta tarea a entornos virtuales y, considerando las nuevas exigencias del espacio, resulta necesario identificar la manera en la que el rol docente ha sido adaptado. Por tal razón, esta investigación pretende analizar la mediación docente en el desarrollo de la comprensión lectora en un entorno virtual de tercer ciclo. Para tal fin, se plantean los objetivos específicos identificar la metodología docente para mediar la comprensión lectora a través de un entorno virtual y describir las estrategias que usa la docente para mediar la comprensión lectora en un entorno virtual. En cuanto a la metodología, la investigación responde a un enfoque cualitativo a nivel descriptivo; por lo tanto, las técnicas se alinean a la entrevista que será contrastada con la observación. Con base en ello, se diseñan y aplican los instrumentos; así, a partir del análisis de la información recogida se concluye, y se identifica como principal aporte, que los mediadores de lectura deben contar con una definición holística de la comprensión lectora, así como ser conscientes de su labor. De este modo, podrán movilizar las capacidades acordes a los niveles y definir las estrategias más adecuadas.Teacher mediation for the development of reading comprehension is a topic full of nuances in education and, because of this, it has been previously investigated in regular contexts. However, Covid 19 mobilized this task to virtual environments and, considering the new demands of the space, it is necessary to identify the way in which the teaching role has been adapted. For this reason, this research aims to analyze teacher mediation in the development of reading comprehension in a virtual environment of the third cycle. To this end, the specific objectives are to identify the teaching methodology to mediate reading comprehension through a virtual environment and to describe the strategies used by the teacher to mediate reading comprehension in a virtual environment. Regarding the methodology, the research responds to a qualitative approach at a descriptive level; therefore, the techniques are aligned to the interview that will be contrasted with observation. Based on this, the instruments are designed and applied; thus, from the analysis of the information collected, it is concluded, and identified as the main contribution, that reading mediators must have a holistic definition of reading comprehension, as well as be aware of their work. In this way, they will be able to mobilize the capacities according to the levels and define the most appropriate strategies

Suggestive evidence of a multi-cytokine resistin pathway in humans and its role on cardiovascular events in high-risk individuals

In cells and tissues resistin affects IL-1β, IL-6, IL-8, IL-12 and TNF-α expression, thus suggesting the existence of a multi-cytokine "resistin pathway". We investigated whether such pathway does exist in humans and, if so, if it is associated with cardiovascular risk factors and with major adverse cardiovascular events (MACE). Serum cytokines were measured in 280 healthy subjects from the Gargano Study 2 (GS2) whose BMI, waist circumference, HOMA IR, triglycerides, HDL-cholesterol, systolic and diastolic blood pressure data were available and in 353 patients with type 2 diabetes and coronary artery disease from the Gargano Heart Study (GHS)-prospective design (follow-up 5.4 ± 2.5 years; 71 MACE). In GS2, cytokines mRNA levels in white blood cells were also measured. In GS2, resistin mRNA was correlated with all cytokines expression (all p < 0.001), but IL-12B. Consistently, serum resistin was correlated with all serum cytokines (all p < 0.001), but IL-12. Expression (eRPS) and serum (sRPS) resistin pathway scores (excluding IL-12) were each other correlated (p < 0.001) and both associated with cardiovascular risk factors (all p < 0.01). In GHS, sRPS was independently associated with MACE (HR = 1.44, 95% CI = 1.10-1.90). Our data indicate the existence of a resistin pathway, which is associated with cardiovascular risk factors and which strongly and independently predicts MACE

Solid-phase extraction of PFOA and PFOS from surface waters on functionalized multi-walled carbon nanotubes followed by UPLC-ESI-MS

This is the first report on the analytical application of multiwalled carbon nanotubes (MWCNTs) as solid-phase extraction (SPE) sorbents for determination in surface waters, at the nanograms per litre level, of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), the two predominant contaminants among the perfluorinated compounds detected. After the preconcentration step, the quantification was achieved by ultraperformance liquid chromatography– electrospray ionization mass spectrometry. To increase the extraction efficiency towards these amphiphilic compounds, MWCNTs were derivatized with amino-terminated alkyl chains, thus producing a mixed-mode material (MWCNT-RNH2) combining hydrophobic affinity and anion-exchange properties. Experiments with distilled, tap and river water (pH 3) spiked at different concentrations (10, 15, 30, 100, 200 and 500 ng L-1) provided absolute recoveries in the range 71–102 % (n=3, relative standard deviations less than 10 %). Analytes were eluted in a single fraction with 6 mL methanol (3×10-4 M NaOH). The within-laboratory reproducibility of the MWCNT-R-NH2 SPE sorbent was evaluated with raw river water, and relative standard deviations less than 15 % were obtained (n=4). Preconcentration factors up to 125 (500-mL sample) made it possible to quantify PFOA and PFOS at low nanograms per litre levels in naturally contaminated river water. The method quantification limits of 10 ng L-1 for PFOA and 15 ng L-1 for PFOS were well below the advisory levels for drinking and surface waters. Comparison with non-derivatized MWCNTs highlighted the role of functionalization in improving the adsorption affinity towards these contaminants. MWCNT-R-NH2 maintained their extraction capability for at least eight repeated adsorption/desorption cycles