The structure-giving role of Rb+ ions for water-ice nanoislands supported on Cu(111).

We characterize the effect of rubidium ions on water-ice nanoislands in terms of area, fractal dimension, and apparent height by low-temperature scanning tunneling microscopy. Water nanoislands on the pristine Cu(111) surface are compared to those at similar coverage on a Rb+ pre-covered Cu(111) surface to reveal the structure-giving effect of Rb+. The presence of Rb+ induces changes in the island shape, and hence, the water network, without affecting the nanoisland volume. The broad area distribution shifts to larger values while the height decreases from three bilayers to one or two bilayers. The nanoislands on the Rb+ pre-covered surface are also more compact, reflected in a shift in the fractal dimension distribution. We relate the changes to a weakening of the hydrogen-bond network by Rb+.

Preparing schools for future pandemics: Insights on water, sanitation and hygiene solutions from the Brazilian school reopening policies.

Post-COVID-19, schools urgently need to enhance infection control and prevention (IPC) measures, including water, sanitation, and hygiene (WASH), to prepare for future outbreaks and pandemics. Particularly in Brazil, that is of particular concern, as students are still recovering from the 20th longest school closure in the world. Hence, the current study had two goals: (i) to describe WASH solutions outlined in policies released at the federal, state, and capital city levels in Brazil during the COVID-19 pandemic for the safe reopening of schools and (ii) to discuss their potential to enhance school's capacity to remain operational during a new pandemic or outbreak. With a qualitative exploratory approach, we performed content analysis to discuss the direction (what, where, how and for whom?) of 66 public policies by integrating four frameworks. Solutions were discussed in the light of the principles of human rights and the human rights to water and sanitation, international guidelines for WASH and IPC in schools and the Sphere minimum standards for humanitarian aid. One hundred and fifty-nine solutions, spanning five thematic areas and five population groups, including software and hardware interventions, were compiled for potential use in Brazil and beyond. While suggested solutions have the potential to provide a cleaner and safer learning environment, it is essential to exercise caution when implementing these measures and adapt them to the specific circumstances of each school.

Potential Antidiabetic Activity of Apis mellifera Propolis Extraction Obtained with Ultrasound.

Recent studies have linked phenolic compounds to the inhibition of digestive enzymes. Propolis extract is consumed or applied as a traditional treatment for some diseases. More than 500 chemical compounds have been identified in propolis composition worldwide. This research aimed to determine Mexican propolis extracts' total phenolic content, total flavonoid content, antioxidant activity, and digestive enzyme inhibitory activity (ɑ-amylase and ɑ-glucosidase). In vitro assays measured the possible effect on bioactive compounds after digestion. Four samples of propolis from different regions of the state of Oaxaca (Mexico) were tested (Eloxochitlán (PE), Teotitlán (PT), San Pedro (PSP), and San Jerónimo (PSJ)). Ethanol extractions were performed using ultrasound. The extract with the highest phenolic content was PE with 15,362.4 ± 225 mg GAE/100 g. Regarding the flavonoid content, the highest amount was found in PT with 8084.6 ± 19 mg QE/100 g. ABTS•+ and DPPH• radicals were evaluated. The extract with the best inhibition concentration was PE with 33,307.1 ± 567 mg ET/100 g. After simulated digestion, phenolics, flavonoids, and antioxidant activity decreased by 96%. In contrast, antidiabetic activity, quantified as inhibition of ɑ-amylase and ɑ-glucosidase, showed a mean decrease in enzyme activity of approximately 50% after the intestinal phase. Therefore, it is concluded that propolis extracts could be a natural alternative for treating diabetes, and it would be necessary to develop a protective mechanism to incorporate them into foods.

Water, sanitation and hygiene (WASH) in schools in Brazil pre-and peri-COVID-19 pandemic: Are schools making any progress?

The previous paucity of data and research on water, sanitation and hygiene (WASH) in schools in Brazil have been preventing an assessment of how safe and healthy schools are to reopen during the COVID-19 pandemic. This study aimed first to assess the current situation of WASH in schools in Brazil and, second, to evaluate to what extent Brazilian schools have been making any progress in providing WASH since the beginning of the COVID-19 pandemic. Data on WASH conditions in schools in Brazil was retrieved from the 2020 and 2021 Brazilian National School Census (BNSC). For the first objective, frequencies of 31 variables were calculated for the whole country and regions, considering all 173,700 schools from BNSC of 2021. Five main variables were considered as indicators of adequate WASH infrastructure in schools. T-test and ANOVA were used to assess differences in these five variables according to the locality, management model and regions. For the second objective only schools presented in both datasets (n = 170,422) were considered to compare WASH in schools pre- and peri-COVID-19 pandemic. Frequencies of 31 variables were calculated for the whole country and regions before and during the pandemic. Paired t-tests were conducted when differences in variables across the years were observed. At the present moment, the majority of schools in Brazil have bathrooms (97%), drinking water with quality suitable for human consumption (95%), improved sanitation facilities (78%) and solid waste collection (70%). Between 2020 and 2021, there was a mix of improvements and deterioration in the school's WASH infrastructure in all regions of the country. Overall, solely considering the WASH infrastructure, schools in the South and Southeast regions of the country are better prepared for the safe reopening. Nevertheless, public schools, schools located in rural areas and the North and Northeast regions of the country, are more in need of WASH interventions. Results indicate that little progress was achieved, and schools in Brazil are still in need of improvements.

Seno preauricular, diferentes tecnicas quirúrgicas / Preauriculares Sinus, different surgical techniques

El seno preauricular es una malformación congénita que se presenta como un pequeño orificio en el oído externo, usualmente cercano al borde anterior de la rama ascendente del hélix. La mayoría son asintomáticos y no requieren tratamiento, sin embargo, una vez infectados se vuelven inflamaciones dolorosas, con secreción fétida que presentan exacerbaciones agudas recurrentes. Objetivo: brindar información actualizada sobre las ventajas de las diferentes técnicas quirúrgicas utilizadas para resolver en forma adecuada este problema congénito. Material y Métodos : el presente estudio se realizó mediante una búsqueda comprensiva de artículos con menos de 10 años de publicación en las bases de datos de MEDLINE/PubMed, Google Académico e HINARI. Se seleccionaron un total de 20 artículos, en español e inglés, entre ellos trabajos originales y metanálisis sobre el tema. Conclusión : la técnica suprauricular ha demostrado, en términos estadísticos, una tasa de recurrencia menor que la técnica clásica de sinectomía...(AU)

Tubos de timpanostomía en niños / Tympanostomy tubes in children

La colocación de tubos de timpanostomía (TT) es la cirugía ambulatoria más frecuentemente practicada en niños. Su objetivo es lograr una adecuada ventilación del oído medio, función normalmente llevada a cabo por la trompa de Eustaquio (TE). La anatomía de la TE en la población pediátrica diiere del adulto, por lo que sus funciones son menos eicaces. La pobre ventilación del oído medio es en parte responsable de la instauración de otitis media aguda. La otitis media aguda recurrente y otitis media con efu - sión pueden afectar la calidad de vida de los pacientes, causando déicit auditivos, retraso del desarrollo del habla y escolar o incluso complicándose en infecciones más severas. La miringotomía con colocación de tubos de ventilación pretende subrogar la función de la TE, con el objetivo de disminuir la incidencia de otitis media, disminuir la severidad de episodios subsecuentes y de restaurar la audición...(AU)

Density functional theory simulation of the adsorption of sulphur multilayers on Au(100).

The adsorption of sulphur multilayers on Au(100) has been studied using density functional theory (DFT) within the generalized gradient approximation (GGA). The first sulphur layer was adsorbed on the four-fold sites of the unreconstructed Au(100) surface forming a lattice. The experimental parameters of the lattice were reproduced taking into account the surface expansion of the topmost Au(100) layer. This expansion should occur when gold islands are formed after the lifting of hex-reconstruction, which allows the lateral movement of the gold atoms. The second sulphur layer, on top of the lattice, consisted of eight S atoms (octomer phase) in a quasi-rectangular arrangement. The structural optimization of the octomer phase was achieved in a specific spatial orientation with respect to the lattice. The analysis of Bader atomic charges and the projected density of states (PDOS) demonstrated that charge transfer from the Au(100) surface to the sulphur layers, sulphur chemisorption and sulphur-sulphur inter-layer mixing of electronic states control the formation of sulphur multilayers.