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Resumen Introducción. Staphylococcus aureus resistente a la meticilina (SARM) es un microorganismo que coloniza las fosas nasales y diferentes partes del cuerpo, lo cual se considera un factor de riesgo para adquirir infecciones invasivas, especialmente en pacientes sometidos a cirugía cardiovascular. Objetivo. Determinar la colonización nasal por SARM y establecer las características clínicas en pacientes programados para cirugía cardiovascular. Materiales y métodos. Se hizo un estudio descriptivo entre febrero y diciembre de 2015. Se incluyeron pacientes adultos programados para cirugía cardiovascular en el Hospital Universitario San Ignacio de Bogotá. La colonización se identificó mediante reacción en cadena de la polimerasa (Polymerase Chain Reaction, PCR) en tiempo real en muestras obtenidas mediante hisopados nasales. Los pacientes fueron descolonizados con mupirocina al 2,0 % intranasal dos veces al día y baños con gluconato de clorhexidina al 4 % del cuello hacía abajo durante cinco días, al cabo de lo cual se hizo una PCR de control. Resultados. Se incluyeron 141 pacientes, 52 hospitalizados y 89 ambulatorios. Del total, 19 (13,4 %) tenían colonización nasal por SARM, correspondientes a 9 (17,3 %) de los 52 hospitalizados y 10 (11,2 %) de los 89 ambulatorios. Todos los pacientes sometidos a descolonización tuvieron resultado negativo en la PCR al final del proceso y ninguno presentó infección del sitio operatorio por S. aureus. Conclusiones. Se demostró colonización nasal por SARM tanto en los pacientes hospitalizados como en los ambulatorios. La descolonización con mupirocina fue efectiva para erradicar el estado de portador a corto plazo, lo que podría tener efecto en las tasas de infección del sitio operatorio en las cirugías cardiovasculares. Abstract Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) is a microorganism that colonizes nostrils and different parts of the body, which is considered a risk factor to acquire invasive infections, especially in cardiovascular surgery patients. Objective: To determine the frequency of nasal colonization by MRSA and to establish the clinical characteristics in patients scheduled for cardiovascular surgery. Materials and methods: This was a descriptive study conducted between February and December, 2015. We included adult patients scheduled for cardiovascular surgery at the Hospital Universitario San Ignacio in Bogotá, Colombia. Colonization was identified by real-time PCR from nasal swabs. Colonized patients were treated with mupirocin 2.0% intranasally twice a day and bathed with chlorhexidine 4% from the neck downwards for five days. At the end of this treatment, PCR control was carried out. Results: We included 141 patients with a percentage of nasal colonization of 13.4% (19/141). There were 52 hospitalized patients and 89 outpatients with a percentage of nasal colonization of 17.3% (9/52), and 11.2% (10/89), respectively. All colonized patients who received treatment had a negative PCR at the end of the regime and none of the participating patients had a surgical site infection by S. aureus at the end of the study. Conclusions: Nasal colonization was observed both in hospitalized patients and outpatients. Decolonization treatment with mupirocin was effective to eradicate the carrier state in the short term, which could impact the rates of surgical wound infection associated with cardiovascular surgery.

Natural stone is an important component of historical heritage (buildings and art objects such as sculptures or rock engravings), and it is still widely used in contemporary works. Soluble salts are the main erosive agent in the built environment, and we review here comparative studies that subject the same rock type to testing with different salt solutions. The results mostly support the accepted notion of the major impact of sodium sulphate, although there are some exceptions. The effects of sodium chloride and calcium sulphate deserve specific discussion given field information on the relevance of these specific salts in the built environment. We relate the information collected to the issues of risk assessment (considering both geochemical conditions and salt effects) and conservation interventions (highlighting the interest of tests that do not produce damage to susceptible materials) and present some methodological suggestions to avoid a case study culture., The Lab2PT-Landscapes, Heritage and Territory laboratory—UIDB/04509/2020 is supported by the Portuguese FCT—“Fundação para a Ciência e a Tecnologia”. The authors also gratefully acknowledge the support of the CERENA (funded by a strategic project of the FCTUIDB/04028/2020) and the LAMPIST of the DECivil, Instituto Superior Técnico, University of Lisbon, Portugal. The University Institute of Geology of the University of A Coruña (Spain) receives support from the Xunta de Galicia from the program “Consolidación y estructuración de unidades de investigación competitivas: Grupos de potencial de crecimiento” (ED431B 2018/47) and Redes de investigación (R2017/008).

[Abstract] Water has always been a critical resource for humans and climate change could aggravate supply problems. In this context, groundwater could be an important reservoir of water, especially given the dispersion of places where it can be obtained and the widespread occurrence of surface marks (springs). Historically, places where groundwater is available have been marked by humans using built structures, with stone materials having a major role. These cultural objects tend to become a part of the collective memory and the historical record (when available) and frequently they stay on the original site along time (hence “marking a spot” for groundwater). However, the development of major water supply structures, especially in the 20th century, promoted the negligence of these ancient water sources. We present a general defense of the importance of recording and preserving cultural stone related to water sources, preferably in the original sites. Conservation of groundwater-related structures could help in the future exploration of this geological resource and converge with historical information on the fountains’ discharge, with geological studies of the terrains and geochemical features of the groundwaters involved, in order to characterize the hydrogeological systems and their potential future use (including the preservation of water quality and properties). These studies could promote a synergetic conservation of both heritage and water. Portugal. Fundação para a Ciência e a Tecnologia; UIDB/04509/2020 Portugal. Fundação para a Ciência e a Tecnologia; UIDB/04028/2020 Xunta de Galicia; ED431B 2018/47 Xunta de Galicia; R2017/008 The Lab2PT-Landscapes, Heritage and Territory laboratory—UIDB/04509/2020 is supported by the Portuguese FCT—“Fundação para a Ciência e a Tecnologia”. The authors also gratefully acknowledge the support of the CERENA (funded by a strategic project of the FCT UIDB/04028/2020) and the LAMPIST of the DECivil, Instituto Superior Técnico, University of Lisbon, Portugal. The University Institute of Geology of the University of A Coruña (Spain) receives support from the Xunta de Galicia from the program “Consolidación y estructuración de unidades de investigación competitivas: Grupos de potencial de crecimiento” (ED431B 2018/47) and Redes de investigación (R2017/008). We also thank the IACOBUS Program from the European Strategic Group of Territorial Cooperation Galicia/North of Portugal for support for the last author The Lab2PT-Landscapes, Heritage and Territory laboratory—UIDB/04509/2020 is supported by the Portuguese FCT—“Fundação para a Ciência e a Tecnologia”. The authors also gratefully acknowledge the support of the CERENA (funded by a strategic project of the FCT UIDB/04028/2020) and the LAMPIST of the DECivil, Instituto Superior Técnico, University of Lisbon, Portugal. The University Institute of Geology of the University of A Coruña (Spain) receives support from the Xunta de Galicia from the program “Consolidación y estructuración de unidades de investigación competitivas: Grupos de potencial de crecimiento” (ED431B 2018/47) and Redes de investigación (R2017/008). We also thank the IACOBUS Program from the European Strategic Group of Territorial Cooperation Galicia/North of Portugal for support for the last author

The crystallization behaviour of jarosite and schwertmannite has been studied by precipitation-aging experiments performed using different parent-solution concentrations at acidic conditions and ambient temperature. Schwertmannite exhibits low crystallinity and is the only mineral identified during low-concentration (LC) experiments. However, in high-concentration (HC) experiments, a relatively rapid Ostwald ripening process leads to the transformation of schwertmannite into natrojarosite. The presence of sodium modifies the morphology and stability of the obtained phases. TEM observations reveal that schwertmannite particles consist of disoriented nanodomains (~6 nm) spread in an amorphous mass. In contrast, natrojarosite particles exhibit a single-domain, highly crystalline core, with the crystallinity decreasing from core to rim. The thermal behaviour of these phases depends on both their composition and their degree of crystallinity. TG and DTG analyses show that, below 500 &deg, C, the amount of structural water is clearly higher in schwertmannite than in natrojarosite. The present results highlight the role of the ripening processes in epigenetic conditions and could be important in interpreting the formation of jarosite in Earth and Martian surface environments.

This work contributes to the knowledge of colloidal and thermal properties of some important primary-originated kaolin deposits from Bolivar State, Venezuela, and their possible use as semisolid formulations in medicinal muds for topical applications. Eight selected high purity kaolin samples were characterized. Rheological and thermal properties were correlated to physico-chemical characteristics of the clay suspensions (pH, Ca2+, and Mg2+ cation desorption and surface charge). Most of the studied kaolin pastes showed adequate viscosities, acceptable skin safe pH, and good thermal properties for pelotherapeutic uses. Three of the studied samples, in particular, showed very high kaolinite purities (&gt, 92% kaolinite), elevated viscosities (&gt, 1 Pas), and good thermal and pH performances for topical application.

Characterization directed to evaluate health care usefulness of kaolinitic samples from various deposits from the south of Venezuela exploited used as raw materials in ceramics have been done Identity, purity and richness in mineral phases and presence of chemical impurities were compared to pharmaceutical grade kaolins and correlated to international requirements described in pharmacopoeias. Color parameters and textural analysis were used as a complementary characterization of the suitability of the samples as a diluent for pharmaceutical oral dosage forms. Most of the samples would require purification before considering their use as health care ingredients. In particular, treatment to eliminate quartz as a mineral impurity or Pb as metallic impurity would be advisable for some of the studied kaolins. Nevertheless, at least seven of the studied samples could be used directly, as they are comparable to commercial kaolin used as excipients or cosmetic ingredients., Authors gratefully acknowledge Laboratory Technicians of IACT (Spain) and IVIC (Venezuela). The study was financed by the Spanish Project CGL2016-80833R, and by the Andalusian Group CTS-946 and Torres Quevedo Contract (PTQ-15-07625).

Comprehensive geochemical analyses (bulk parameters, major and trace elements, organic matter, mineralogy and particle analysis) were carried out on sediments from seven lakes on Fildes Peninsula, King George Island. The resulting compositional dataset was subjected to principal component analysis and cluster analysis. The results showed that four different lacustrine sedimentary environments can be distinguished: i) lakes 1 and 2 with relatively high values of secondary aluminous clay minerals, ii) lake 4 with anthropogenic enrichment of Co, Cu and Zn, iii) lake 7 with relatively high values of Ba and P and a high zeolite content, and iv) all the other studied lakes. Our results indicate moderate chemical weathering in all lacustrine sediments and that the distance to the glacial ice margin is one of the most important factors influencing the chemical weathering in the area. Furthermore, depositional processes have little influence on the geochemistry of the investigated elements and that local bedrock is the main source of sediments in the lakes on Fildes Peninsula.

Magnetic nanoparticles (NPs) of magnetite Fe3O4 obtained by coprecipitation (COP), thermal decomposition (DT), and commercial sample (CM) have been degraded in similar conditions to physiological medium at pH 4.7 and in simulated body fluid (SBF) at pH 7.4. The formation of the nanoparticles was confirmed by FTIR spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). In view of medical and environmental applications, the stability of the particles was measured with dynamic light scattering. The degradation processes were followed with atomic absorption spectroscopy (EAA) and TEM. Magnetic measurements were carried out using vibrating sample magnetometry (VSM). Our results revealed that the structural and magnetic properties of the remaining nanoparticles after the degradation process were significantly different to those of the initial suspension. The degradation kinetics is affected by the pH, the coating, and the average particle size of the nanoparticles.

Remains of selachians (sharks and rays) and other icthiolites have been collected from the Upper Mio- cene locality of Lomas de Siquirres. A new record of fossil species of shark is described for Central America and the Caribbean Region: Carcharhinus albimarginatus (Rüpel, 1837). The fauna of the Río Banano Formation is notable for the Tethysian affinity with the paleomediterranean faunas. Restos de seláceos (tiburones y rayas) y otros ictiolitos fueron recolectados de la localidad de Lomas de Siquirres de edad Mioceno Superior. Se describe un nuevo registro de especie fósil de tiburón para América Central y la Región Caribe: Carcharhinus albimarginatus (Rüpel, 1837). La fauna de la Formación Río Banano se caracteriza por su afinidad Tethysiana con las faunas paleomediterráneas.

In current global age youth have drifted apart from traditional forms of exercising political rights (e.g., voting) and have engaged in new forms of social and political participation. The beliefs and aspirations of such forms of citizenship and the motivations underlying new forms of participation have not been the focus of research. This study explores the beliefs and aspirations of citizenship in a sample of 24 Chilean youth, males and females of diverse socioeconomic condition. Participants had a history of participation in political, ethno-political, and ecological organizations. A qualitative methodology with in-depth semi-structured individual interviews and focus groups was used. Findings indicate that youth’s central motivation is to change the lack of validation of people within the current sociopolitical system, due to vulnerability of rights, social disparities, and lack of voice and power of citizens. Participants endorse a notion of citizenship that values citizens’ responsibility to be informed and to deliberate. Values of fraternity, dignity, and equity underlie youth’s beliefs and aspirations of citizenship.