Caffeine photocatalytic degradation using composites of NiO/TiO2–F and CuO/TiO2–F under UV irradiation

The interest in the removal of emerging contaminants has increased in the last decade. Photocatalytic degradation using p-n heterojunctions could effectively provide the degradation of these type of substances that are persistent in the environment. In this work, the synthesis, characterization, and photocatalytic evaluation of TiO2–F as well as CuO/TiO2–F and NiO/TiO2–F composite materials were studied in the photo-assisted degradation of caffeine using UV radiation. The fluorination of titanium dioxide induced changes in some physicochemical properties of the materials, which contributed to a decrease in surface area and bandgap energy as well as an increase in crystallite size as compared to pristine TiO2. ≡Ti–F species were evidenced to be formed, which could favor charge separation processes. A highest segregation of CuO species in comparison with NiO on the surface of TiO2–F could be formed, which could increase defect sites and decrease the band gap. The formation of a heterojunction between the semiconductors was evidenced, responsible for the observed improvements in photocatalytic properties of the composite materials. The photocatalytic tests evidenced an important degradation of caffeine; however, mineralization was incomplete. The stability of the composite materials and their potential use in the photocatalytic treatment of caffeine was evaluated by reuse tests

Cytological effects of pulsed electromagnetic fields and static magnetic fields induced by a therapeutic device on in vivo exposed rats

Background: There is a trend towards the use of magnetic fields in medicine. Pulsed electromagnetic fields (PEMFs) technology was based upon 20 years of fundamental studies on the electromechanical properties of bone and other connective tissues. More recently, these magnetic fields have been used to treat several health conditions. There remains continuing concern that exposure to electromagnetic devices may cause adverse effects. The aim of the present study was to investigate the cytological effects induced in rats exposed in a patented medical device that uses PEMFs combined with static magnetic fields (SMFs).Material and Methods: Thirty sexually mature 14-week-old male and female Sprague Dawley rats were distributed into three groups: (a) 5 males and 5 females (independently) exposed to PEMFs combined with SMFs, (b) animals treated with SMFs only, and (c) non-exposed animals. Acridine orange fluorescent-staining micronucleus test and male germ cells analysis were performed according to standardized techniques.Results: A lack of evidence for alterations on micronucleus frequency, on polychromatic erythrocytes percentage, and on sperm counts and morphological characteristics of male germ cells were found in mature rats exposed to PEMFs medical device compared to non-exposed animals.Conclusions: This study suggests that the applied magnetic field generated in a therapeutic device did not have any detectable cytotoxic or genotoxic effect in exposed rats. In view of these findings and the contradictory reports in the literature, it is necessary to carry out more research to help clarify the controversy concerning cytogenotoxic risk associated with therapeutic magnetic fields exposures.Keywords: Cytotoxicity, pulsed electromagnetic fields, static magnetic fields, micronuclei, sperm abnormalitie

Structural modulation and direct measurement of subnanometric bimetallic PtSn clusters confined in zeolites

[EN] Modulating the structures of subnanometric metal clusters at the atomic level is a great synthetic and characterization challenge in catalysis. Here, we show how the catalytic properties of subnanometric platinum clusters (0.5-0.6 nm) confined in the sinusoidal 10R channels of purely siliceous MFI zeolite are modulated upon introduction of partially reduced tin species that interact with the noble metal at the metal/support interface. The platinum-tin clusters are stable in H(2)over an extended period of time (>6 h), even at high temperatures (for example, 600 degrees C), which is determined by only a few additional tin atoms added to the platinum clusters. The structural features of platinum-tin clusters, which are not immediately visible by conventional characterization techniques but can be established after combination of in situ extended X-ray absorption fine structure, high-angle annular dark-field scanning transmission electron microscopy and CO infrared data, are key to providing a one-order of magnitude lower deactivation rate in the propane dehydrogenation reaction while maintaining high intrinsic (initial) catalytic activityThis work was supported by the European Union through the European Research Council (grant ERC-AdG-2014-671093, SynCatMatch) and the Spanish government through the "Severo Ochoa Program" (SEV-2016-0683). L.L. thanks the ITQ for providing a contract. The authors also thank the Microscopy Service of the UPV for the TEM and STEM measurements. The XAS measurements were carried out in the CLAESS beamline of the ALBA synchrotron. We thank Giovanni Agostini for his kind support in the analysis of XAS data. HR-HAADF-STEM measurements were performed at DME-UCA at Cadiz University with financial support from FEDER/MINECO (MAT2017-87579-R and MAT2016-81118-P). C.W.L. thanks CAPES (Science without Frontiers -Process no. 13191/13-6) for a predoctoral fellowship. The financial support from ExxonMobil for this project is also greatly acknowledged.Liu, L.; Lopez-Haro, M.; Lopes, CW.; Rojas-Buzo, S.; Concepción Heydorn, P.; Manzorro, R.; Simonelli, L.... (2020). Structural modulation and direct measurement of subnanometric bimetallic PtSn clusters confined in zeolites. Nature Catalysis. 3(8):628-638. https://doi.org/10.1038/s41929-020-0472-7S62863838Liu, L. & Corma, A. Metal catalysts for heterogeneous catalysis: from single atoms to nanoclusters and nanoparticles. Chem. Rev. 118, 4981–5079 (2018).An, K. & Somorjai, G. A. Nanocatalysis I: synthesis of metal and bimetallic nanoparticles and porous oxides and their catalytic reaction studies. Catal. 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Mental Disorders and Level of Resilience in Eight High-Altitude Cities of Peru during the Second Pandemic Wave: A Multicenter Population-Based Study

COVID-19 has led us to take preventive measures, such as social isolation, to reduce the high transmissibility of the disease. This could have affected the mental health of various population groups and the development of resilience as a mitigator. A cross-sectional analytical study was conducted with 700 participants from eight cities. The dependent variables were depression, anxiety, and post-traumatic stress disorder (PTSD). The independent variable was resilience. Generalized logistic regressions were used to identify the associations between the variables. The population consisted mostly of university students (65.0%); the rest of the population was distributed among workers of public or private institutions, housewives, and others (35.0%). High prevalences of anxiety (72.7%), depression (64.1%), and PTSD (15.1%) were found, as well as a median (interquartile range) resilience score of 24 points was determined. Factors associated with a high prevalence of PTSD were having lost employment and having a family member who died from COVID-19. For depression, associated factors were severe food insecurity and hypersomnia. For anxiety, associated factors were were having a deceased family member with COVID-19 and mild food insecurity. Our results show that, during the pandemic, the general population had a higher prevalence of mental disorders. In addition, anxiety was the most prevalent of the dependent variables. Special attention should be paid to the factors influencing the development of mental disorders and mental health prevention and promotion programs should be established

Evaluation of the in vitro and in vivo efficacy of ruthenium polypyridyl compounds against breast cancer

[Abstract] The clinical success of cisplatin, carboplatin, and oxaliplatin has sparked the interest of medicinal inorganic chemistry to synthesize and study compounds with non-platinum metal centers. Despite Ru(II)–polypyridyl complexes being widely studied and well established for their antitumor properties, there are not enough in vivo studies to establish the potentiality of this type of compound. Therefore, we report to the best of our knowledge the first in vivo study of Ru(II)–polypyridyl complexes against breast cancer with promising results. In order to conduct our study, we used MCF7 zebrafish xenografts and ruthenium complexes [Ru(bipy)2(C12H8N6-N,N)][CF3SO3]2Ru1 and [{Ru(bipy)2}2(μ-C12H8N6-N,N)][CF3SO3]4Ru2, which were recently developed by our group. Ru1 and Ru2 reduced the tumor size by an average of 30% without causing significant signs of lethality when administered at low doses of 1.25 mg·L−1. Moreover, the in vitro selectivity results were confirmed in vivo against MCF7 breast cancer cells. Surprisingly, this work suggests that both the mono- and the dinuclear Ru(II)–polypyridyl compounds have in vivo potential against breast cancer, since there were no significant differences between both treatments, highlighting Ru1 and Ru2 as promising chemotherapy agents in breast cancer therapy.Xunta de Galicia; ED431C 2018/39Portugal. Fundação para a Ciência e a Tecnologia; PEst 2015-2020Portugal. Fundação para a Ciência e a Tecnologia; UID/Multi/04349/2013Portugal. Fundação para a Ciência e a Tecnologia; RECI/QEQ-QIN/0189/2012Portugal. Fundação para a Ciência e a Tecnologia; UID/QUI/00100/2020Portugal. Fundação para a Ciência e a Tecnologia; UIDP/04378/2020Portugal. Fundação para a Ciência e a Tecnologia; UIDB/04378/2020Portugal. Fundação para a Ciência e a Tecnologia; LA/P/0140/202

The Antimicrobial Scrub Contamination and Transmission (ASCOT) Trial: A Three-Arm, Blinded, Randomized Controlled Trial With Crossover Design to Determine the Efficacy of Antimicrobial-Impregnated Scrubs in Preventing Healthcare Provider Contamination

OBJECTIVE To determine whether antimicrobial-impregnated textiles decrease the acquisition of pathogens by healthcare provider (HCP) clothing. DESIGN We completed a 3-arm randomized controlled trial to test the efficacy of 2 types of antimicrobial-impregnated clothing compared to standard HCP clothing. Cultures were obtained from each nurse participant, the healthcare environment, and patients during each shift. The primary outcome was the change in total contamination on nurse scrubs, measured as the sum of colony-forming units (CFU) of bacteria. PARTICIPANTS AND SETTING Nurses working in medical and surgical ICUs in a 936-bed tertiary-care hospital. INTERVENTION Nurse subjects wore standard cotton-polyester surgical scrubs (control), scrubs that contained a complex element compound with a silver-alloy embedded in its fibers (Scrub 1), or scrubs impregnated with an organosilane-based quaternary ammonium and a hydrophobic fluoroacrylate copolymer emulsion (Scrub 2). Nurse participants were blinded to scrub type and randomly participated in all 3 arms during 3 consecutive 12-hour shifts in the intensive care unit. RESULTS In total, 40 nurses were enrolled and completed 3 shifts. Analyses of 2,919 cultures from the environment and 2,185 from HCP clothing showed that scrub type was not associated with a change in HCP clothing contamination ( P =.70). Mean difference estimates were 0.118 for the Scrub 1 arm (95% confidence interval [CI], −0.206 to 0.441; P =.48) and 0.009 for the Scrub 2 rm (95% CI, −0.323 to 0.342; P =.96) compared to the control. HCP became newly contaminated with important pathogens during 19 of the 120 shifts (16%). CONCLUSIONS Antimicrobial-impregnated scrubs were not effective at reducing HCP contamination. However, the environment is an important source of HCP clothing contamination. TRIAL REGISTRATION Clinicaltrials.gov Identifier: NCT 02645214 Infect Control Hosp Epidemiol 2017;38:1147–115

Lugares, recorridos y sentidos de la memoria histórica: acercamientos metodológicos

244 páginasEste libro es una iniciativa de los Grupos Regionales de Memoria Histórica (GRMH), que, junto con el Centro Nacional de Memoria Histórica desde el 2013 generaron propuestas para la construcción de memoria histórica en Colombia. El objetivo de la consolidación de los GRMH ha sido reconocer procesos de investigación locales que hacen profesores universitarios para tejer puentes entre las instituciones del país y comunidades victimizadas en el marco del con icto armado interno de Colombia. Aunque las apuestas de investigación social participativa se nutren de múltiples aristas, disciplinas y escuelas de pensamiento, existen particularidades metodológicas en las investigaciones que se formulan en clave de memoria histórica que, en esta ocasión, son transversales y se profundizan en cada capítulo.La fuerza de la memoria: hilos, nudos y reflexiones de una trayectoria colectiva || Introducción || El objeto-relato como dispositivo de memoria: el caso del grupo de alabao de pogue, bojayá, chocó || Metodologías colaborativas y memorias con potencial transformador en la comunidad de Puerto Gaviotas, Calamar, Guaviar