Three-dimensional line edge roughness in pre- and post-dry etch line and space patterns of block copolymer lithography.

In this work, we employ large-scale coarse-grained molecular dynamics (CGMD) simulations to study the three-dimensional line edge roughness associated with line and space patterns of chemo-epitaxially directed symmetric block copolymers (BCPs) on a flat substrate. The di-block copolymer chain length and interaction parameters are validated with the experimental BCP period, L0 and corresponding molecular weight. Defect-free lamellae are formed, after which the system is quenched below the glass transition temperature before selectively dry-etching off one of the BCP phases. The effect of varying etch-selectivity on post-etch resist domain morphology was studied. The roughness of the polymer domain was evaluated over three process stages: annealing, pre-etching, and post-etching. Power spectral density plots were then generated to elucidate the contributions of low and high frequency roughness for the three process stages. The roughness results obtained from simulations are shown to be in close agreement with the roughness result obtained from analyzing experimental SEM images. Parameters like the Hurtz roughness exponent and correlation length inherent to the process and the BCP were also revealed from the experimental study.

[Clinical Characteristics and outcomes of adults with COVID-19 admitted to a Pediatric Intensive Care Unit]. / Características y resultados clínicos de adultos graves hospitalizados por COVID-19 en una Unidad de Cuidados Intensivos Pediátricos.

OBJECTIVE: To describe a cohort of critically ill adult patients suffering from COVID-19, admitted to a pediatric intensive care unit managed by a pediatric intensive care team (ICU-MP). PATIENTS AND METHOD: Retrospective observational study of adults admitted to the ICU-MP due to COVID-19 from May 11 to July 26, 2020. Demographic, clinical, biochemical, ventilatory support characteris tics, and complications were recorded. Disease severity was characterized by Acute Physiology and Chronic Health Evaluation II score (APACHE II) using data from the first 24 hours of admission to the ICU-MP. RESULTS: Ninety-three patients over 18 years with suspected or confirmed COVID-19 were admitted to the ICU-MP. The median age was 60.3 years (SD 13.9), and 59 (63.4%) patients were male. Eighty-two (88.1%) patients had at least 1 medical comorbidity. The median APACHE II score was 9.4 points (SD 5.6). Fifty-one (54.8%) patients were invasively ventilated, for a median of 13.7 days (SD 17.9). Inotropic support was used in 45 (48%) patients. Thirty-three (35.5%) patients presented acute kidney injury (AKI) and 14 (15.1%) patients received continuous renal replacement therapy. Twenty-nine (31.2%) patients had healthcare-associated infections. The median ICU-MP stay was 10.8 days (SD 11.8). 25 (26.9%) patients died, ten of them (40%) had adequacy of thera peutic effort. CONCLUSIONS: The mortality rate of critically ill patients with COVID-19 is high. Older patients (> 70 years), those who require invasive mechanical ventilation and who develop AKI are at increased risk of death. Although this is not a comparative study, our mortality rate and complica tions seem to be similar to those reported in adult case series.

SARS-CoV-2 infection in asymptomatic healthcare workers at a clinic in Chile.

Asymptomatic SARS-CoV-2 infection of healthcare workers (HCWs) has been reported as a key player in the nosocomial spreading of COVID-19. Early detection of infected HCWs can prevent spreading of the virus in hospitals among HCWs and patients. We conducted a cross-sectional study to determine the asymptomatic infection of HCWs in a private clinic in the city of Santiago, Chile. Our study was conducted during a period of 5 weeks at the peak of transmission of SARS-CoV-2 in Chile. Nasopharyngeal samples were obtained from 413 HCWs and tested for the presence of SARS-CoV-2 using RT-qPCR. We found that a 3.14% of HCWs were positive for the presence of SARS-CoV-2 (14/413). Out of these, 7/14 were completely asymptomatic and did not develop symptoms within 3 weeks of testing. Sequencing of viral genomes showed the predominance of the GR clade; however, sequence comparison demonstrated numerous genetic differences among them suggesting community infection as the main focus of transmission among HCWs. Our study demonstrates that the protocols applied to protect HCWs and patients have been effective as no infection clusters due to asymptomatic carriers were found in the clinic. Together, these data suggest that infection with SARS-CoV-2 among HCWs of this health center is not nosocomial.

Hypoglycemic and antioxidant effects of green tomato (Physalis ixocarpa Brot.) calyxes' extracts.

The aim of this study was to evaluate the hypoglycemic and antioxidant potential of green tomato (Physalis ixocarpa Brot.) calyxes' extracts. Three methods were used to obtain the extracts: maceration (M), ultrasound-assisted (US), and infusion. Regarding in vitro hypoglycemic evaluation, glucose diffusion assay and enzymatic inhibitory action of α-amylase and α-glucosidase were performed. Whereas, for in vivo assessment an oral starch tolerance test (OSTT) was tested with aqueous extracts [infusion (40 mg/kg b. wt.), maceration (M) water (98 mg/kg b. wt.), and US water (82.24 mg/kg b. wt.)] on male Wistar rats. Additionally, in vitro antioxidant activity of P. ixocarpa calyxes' was evaluated through inhibition of scavenging radical assay and lipid peroxidation. Extracts decreased the glucose diffusion in a range of 18%-56% compared with the negative control. Additionally, extracts inhibited α-amylase (above 80%) and α-glucosidase enzymes (above 90%). All groups treated with P. ixocarpa calyxes' significantly reduced the glucose levels at 120 min (infusion = 13.3%, M Water = 12.7%, and US Water = 19.4%) in comparison with the negative control, and similar levels to acarbose at 120 min (13.1%). Finally, extracts showed IC50 values in a range of 2.5-6.6 µg/µl for radical scavenging, and 118-199 µg/µl for lipid oxidation. Our results show that P. ixocarpa calyxes' extracts induce hypoglycemia and antioxidant effects in vitro and in vivo. PRACTICAL APPLICATIONS: The green tomato is usually consumed in Mexico, the United States, and Central America. This fruit grows inside a calyx, which is considered an agro-food waste. However, some regions of Latin America have a traditional medicine purpose for diabetes affections. To the best of our knowledge, there are no published data that supports its hypoglycemic action. The information provided will be useful to nutraceutical applications that allow value-added products and sustainable green tomato production.

Curso e-learning "desafíos de la pandemia COVID-19 en pediatría": caracterización y relación con los resultados de aprendizaje y grado de satisfacción / E-learning course "challenges of the COVID-19 pandemic in pediatrics": characterization and association with learning results and grade of satisfaction

Frente a la pandemia del CoVID-19, resulta fundamental establecer estrategias manteniendo distanciamiento social, que permitan educar a profesionales de la salud sobre aspectos relacionados con SARS-CoV-2. La Sociedad Chilena de Neumología Pediátrica creó un E-learnig de contingencia de acceso libre. OBJETIVO: Describir las características del curso online "Desafíos de la pandemia CoVID-19 en Pediatría", y evaluar el grado de satisfacción de quienes lo cursaron. Estudio transversal. Todos los inscritos en el curso, entre mayo 2020 y julio 2020. Se grabaron 12 clases dictadas por especialistas con representación académica de Chile. Se realizó una prueba final y una encuesta de satisfacción, con puntaje de 1 a 7. Se realizó análisis descriptivo e inferencial, evaluando asociación entre clasificación final del curso, profesión y zona geográfica de los participantes con test de Kruskal Wallis, significancia estadística p<0,05. Aprobado por comité ética. Participaron 2541 alumnos, 73% mujeres. Mediana de edad 32,7 años. 90,7% de Chile, de estos 63,2% de regiones. De procedencia extranjera destacó Bolivia (2,9%) y Ecuador (2,5%). De los que realizaron la prueba, el 98,6% aprobó. Existió diferencia entre notas según profesión, Médicos-Kinesiólogos(p=0.025) y Médicos-Enfermeros(p=0.002); y según procedencia, Región Metropolitana (RM)-Otras regiones (p=0.041), RM-Internacional(p<0,001) y Otras regiones-Internacional(p<0,001). La evaluación de contenidos ponderó 6,6 y la accesibilidad 6,8. El 98% contestó que el curso cumplió sus expectativas. Concluimos que se inscribió un gran número de alumnos de Chile y Latinoamérica. Más del 98% aprobó la prueba final y refirió un alto nivel de satisfacción. Sugerimos emplear estrategias similares en situaciones de catástrofes sanitarias.

In the face of the CoVID-19 pandemic, it is essential to establish strategies, maintaining social distancing, that allow educating health professionals on aspects related to SARS-CoV-2. The Chilean Society of Pediatric Pulmonology created a free access contingency E-learning. OBJECTIVE: To describe the characteristics of the online course "Challenges of the CoVID-19 pandemic in Pediatrics", and to evaluate the grade of satisfaction of those who attended it.Transversal study. All those enrolled in the course, between May 2020 and July 2020. 12 classes taught by specialists with academic representation from Chile were recorded. A final test and a satisfaction survey were carried out, with a score from 1 to 7. A descriptive and inferential analysis was implemented, evaluating the association between the final classification of the course, profession and geographical area of the participants with the Kruskal Wallis test, statistical significance p< 0.05. Approved by ethics committee. 2541 students participated, 73% women. Median age 32.7 years. 90.7% from Chile, of these 63.2% from regions. Of foreign origin, Bolivia (2.9%) and Ecuador (2.5%) stand out. Of those who took the test, 98.6% were successful. There was a difference between grades according to profession, Physicians-Kinesiologists(p=0.025) and Physicians-Nurses(p=0.002); and according to origin, Metropolitan Region (RM)-Other regions (p=0.041), RM-International (p<0.001) and Other regions-International (p<0.001). The content evaluation pondered 6.6 and accessibility 6.8. 98% responded that the course met their expectations. CONCLUSION: A large number of students from Chile and Latin America were enrolled. More than 98% passed the final test and reported a high level of satisfaction. We suggest using similar strategies in situations of health catastrophes.