Cluster Tool for In Situ Processing and Comprehensive Characterization of Thin Films at High Temperatures.

A new cluster tool for in situ real-time processing and depth-resolved compositional, structural and optical characterization of thin films at temperatures from -100 to 800 °C is described. The implemented techniques comprise magnetron sputtering, ion irradiation, Rutherford backscattering spectrometry, Raman spectroscopy, and spectroscopic ellipsometry. The capability of the cluster tool is demonstrated for a layer stack MgO/amorphous Si (∼60 nm)/Ag (∼30 nm), deposited at room temperature and crystallized with partial layer exchange by heating up to 650 °C. Its initial and final composition, stacking order, and structure were monitored in situ in real time and a reaction progress was defined as a function of time and temperature.

Synthesis and Characterization of Multilayered CrAlN/Al2O3 Tandem Coating Using HiPIMS for Solar Selective Applications at High Temperature.

The effect of applying a negative bias during deposition of a previously designed multilayer solar selective absorber coating was studied on two types of substrates (316L stainless steel and Inconel 625). The solar selective coating is composed of different chromium aluminum nitride layers deposited using a combination of radiofrequency (RF), direct current (DC), and high-power impulse magnetron sputtering (HiPIMS) technologies. The chemical composition is varied to generate an infrared reflective/absorber layer (with low Al addition and N vacancies) and two CrAlN intermediate layers with medium and high aluminum content (Al/Cr = 0.6 and 1.2). A top aluminum oxide layer (Al2O3) is deposited as an antireflective layer. In this work, a simultaneous DC-pulsed bias (-100 V, 250 kHz) was applied to the substrates in order to increase the film density. The optical performance, thermal stability, and oxidation resistance was evaluated and compared with the performance obtained with similar unbiased coating and a commercial Pyromark paint reference at 600, 700, and 800 °C. The coating remained stable after 200 h of annealing at 600 °C, with solar absorptance (α) values of 93% and 92% for samples deposited on stainless steel and Inconel, respectively, and a thermal emittance ε25°C of 18%. The introduction of additional ion bombardment during film growth through bias assistance resulted in increased durability, thermal stability, and working temperature limits compared with unbiased coatings. The solar-to-mechanical energy conversion efficiency at 800 °C was found to be up to 2 times higher than Pyromark at C = 100 and comparable at C = 1000.

Synthesis and Characterisation of ASA-PEEK Composites for Fused Filament Fabrication.

In this paper, a series of polymer composites made from acrylonitrile-styrene-acrylate (ASA) and poly (ether ether ketone) (PEEK) were manufactured. ASA acts as a polymer matrix while PEEK is loaded in the form of micro-particles that act as a reinforcing filler. The composites were compounded by single screw extrusion and then, different specimens were manufactured either via injection moulding (IM) or fused filament fabrication (FFF). Two different types of PEEK (commercial and reused) in different concentrations (3 and 6 wt.%) were tested and their influence in the mechanical, structural, and thermal properties were studied. It was observed that reused PEEK enhanced the stiffness and tensile strength and thermal stability of the composites both, for injected and printed specimens. This evidences the suitability of these composites as potential candidates as novel materials with enhanced properties following an approach of circular economy.

COVID-19 in Children: Clinical Manifestations and Pharmacologic Interventions Including Vaccine Trials.

Children usually present with milder symptoms of COVID-19 as compared with adults. Supportive care alone is appropriate for most children with COVID-19. Antiviral therapy may be required for those with severe or critical diseases. Currently there has been a rapid development of vaccines globally to prevent COVID-19 and several vaccines are being evaluated in children and adolescents. Currently, only the Pfizer-BioNTech messenger RNA vaccine is approved for emergency authorization use in the pediatric population ages 16 years and older.

Towards nanometric resolution in multilayer depth profiling: a comparative study of RBS, SIMS, XPS and GDOES.

An increasing amount of effort is currently being directed towards the development of new functionalized nanostructured materials (i.e., multilayers and nanocomposites). Using an appropriate combination of composition and microstructure, it is possible to optimize and tailor the final properties of the material to its final application. The analytical characterization of these new complex nanostructures requires high-resolution analytical techniques that are able to provide information about surface and depth composition at the nanometric level. In this work, we comparatively review the state of the art in four different depth-profiling characterization techniques: Rutherford backscattering spectroscopy (RBS), secondary ion mass spectrometry (SIMS), X-ray photoelectron spectroscopy (XPS) and glow discharge optical emission spectroscopy (GDOES). In addition, we predict future trends in these techniques regarding improvements in their depth resolutions. Subnanometric resolution can now be achieved in RBS using magnetic spectrometry systems. In SIMS, the use of rotating sample holders and oxygen flooding during analysis as well as the optimization of floating low-energy ion guns to lower the impact energy of the primary ions improves the depth resolution of the technique. Angle-resolved XPS provides a very powerful and nondestructive technique for obtaining depth profiling and chemical information within the range of a few monolayers. Finally, the application of mathematical tools (deconvolution algorithms and a depth-profiling model), pulsed sources and surface plasma cleaning procedures is expected to greatly improve GDOES depth resolution.

Threshold Static Automated Perimetry of the Full Visual Field in Idiopathic Intracranial Hypertension.

Purpose: To characterize visual loss across the full visual field in idiopathic intracranial hypertension (IIH) patients with mild central visual loss. Methods: We tested the full visual field (50° nasal, 80° temporal, 30° superior, 45° inferior) of 1 eye of 39 IIH patients by using static perimetry (size V) with the Open Perimetry Interface. Participants met the Dandy criteria for IIH and had at least Frisén grade 1 papilledema with better than -5 dB mean deviation (MD) centrally. Two observers (MW and AS) evaluated the visual field defects, adjudicated any differences, and reviewed optical coherence tomography data. Results: We found a greater MD loss peripherally than centrally (central 26°). The median MD (and corresponding median absolute deviations) was -1.37 dB (1.61 dB) for the periphery and -0.77 dB (0.87 dB) for the central 26°, P < 0.001. There were about 30% more abnormal test locations identified in the periphery (P = 0.12), and the mean defect depth increased with eccentricity (P < 0.001). The most frequent defect found was a temporal wedge (23% of cases) in the periphery with another 23% that included this sector with inferior temporal loss. Although the presence of papilledema limited correlation, 55% of the temporal wedge defects had optical coherence tomography retinal nerve fiber layer deficits in the corresponding superonasal location. Other common visual field defects were inferonasal loss, superonasal loss, and superior and inferior arcuate defects. Seven patients (18%) had visual field defects in the periphery with normal central visual field testing. Conclusion: In IIH patients, we found substantial visual loss both outside 30° of the visual field and inside 30° with the depth of the defect increasing linearly with eccentricity. Temporal wedge defects were the most common visual field defect in the periphery. Static threshold perimetry of the full visual field appears to be clinically useful in IIH patients.

Formation of antireflection Zn/ZnO core-shell nano-pyramidal arrays by O2+ ion bombardment of Zn surfaces.

ZnO is probably one of the most studied oxides since ZnO nanostructures are a very rich family of nanomaterials with a broad variety of technological applications. Although several chemical techniques offer the possibility to obtain such ZnO nanostructures, here we show that the controlled modification of the zinc surface by low-energy O2+ bombardment leads to the formation of core-shell Zn/ZnO nano-pyramidal arrays that suppress the reflection of light decreasing the reflectivity below 6% in the wavelength range of 300-900 nm. This controlled and scalable protocol opens the door to a broad range of possibilities for the use of ion bombardment to produce surface modifications for technological applications in the field of photoelectric devices and solar cells.

Adenocarcinoma mucinoso de apéndice cecal asociado a amputación apendicular: revisión y reporte de un caso / Mucinous adenocarcinoma of the appendix associated with cecal appendage amputation: review and a case report

Los tumores de apéndice cecal son poco frecuentes, de todos ello los adenocarcinomas representan un 0,14 por ciento del total de apendicectom¡as, siendo los segundos en frecuencia después de los tumores carcinoides. No se encontró en la literatura ningún caso de amputación de apéndices secundario a cáncer primario del mismo, por lo que presentamos el caso de una paciente femenina de 42 años, quien consulta con dolor en fosa iliaca derecha, ingresada con diagnóstico de absceso pélvico, llevada a pabellón donde se evidencia una tumoración aparentemente de origen mesentérico, cercana al sigmoides, la cual es resecada en la biopsia un adenocarcinoma mucinoso de apéndice. Reintervenida, en donde se verifica la amputación del apéndice se confirma nuevamente el diagnóstico histológico así como por inmunohistoquímica. Es llevada nuevamente a quirófano para hemicolectomía derecha. Los adenocarcinomas son tumores de origen glandular que en el apéndice pueden ser: Mucinoso, colonico, adenocarcinoide. Son de crecimiento rápido, acompañados de necrosis, generalmente se originan en la base apendicular. Son mas frecuentes a partir de la cuarta década de la vida, no muestran predilección por sexo. Clínicamente en la mayoría de los casos semejan un cuadro de apendicitis, siendo el dolor abdominal el síntoma mas frecuente. El diagnóstico en la mayoría de los casos en trans o postoperatorio (biopsia). Las metástasis se dan por vía y por continuidad. El tratamiento de elección es la hemiolectomía derecha (mayor sobrevida en relación con la apendicectomía simple).

TVT (cinta vaginal libre de tensión) nuevo tratamiento para la incontinencia urinaria de esfuerzo: experiencia en el Hospital Patrocinio Peñuela Ruíz / TVT (vaginal type free of tension) new treatment for the incontinence urinaria of effort: experience in the Hospital Patrocinio Peñuela Ruíz

Descripción de la técnica quirúrgica y evaluación en nuestra casuística del tratamiento de la incontinencia urinaria de esfuerzo con cinta vaginal libre de tensión (TVT). Se realizo una revisión de la literatura acerca de este nuevo método. Se revisaron las historias de las pacientes sometidas a este procedimiento en el Hospital Patrocinio Peñuela Ruíz, recolectando datos en tablas para la evaluación y análisis de la misma. Se encontraron un total de 14 casos, con un promedio de edad de 50 años. Se presentaron (2) casos de perforación de vejiga (14,2 por ciento), dos (2) casos presentaron retención urinaria en el postoperatorio inmediato (14,2 por ciento). La tasa de curación subjetiva fue de 81,8 por ciento. La mayoría de los casos fueron intervenidos en forma ambulatoria. Los resultados obtenidos son equiparables con los publicados en otras series. Concluimos se trata de una técnica sencilla, de fácil aprendizaje, con tiempo quirúrgico corto y corta estancia postoperatoria, siendo así una buena elección en el tratamiento de la incontinencia urinaria de esfuerzo.

¿Son las apendices lo que parecen? correlación clínico-histológica de la apendicitis aguda: Hospital "Dr. Patrocinio Peñuela Ruíz": 1999-2000 San Cristóbal-Venezuela / Appendixes are what they seem? histological correlation of acute appendicitis: Hospital Dr. Patrocinio Peñuela Ruiz: 1999-2000 San Cristobal-Venezuela

Las fases hispatológicas de la Apendicitis Aguda se usan para la descripción de los hallazgos intraoperatorios por parte de los cirujanos. Siendo la fase en que se encuentra el apéndice importante para escoger el tratamiento subsecuente, actualmente no contamos con el estudio histopatológico en postoperatorio inmediato. Quisimos verificar si los hallazgos intraoperatorios coinciden con los histopatológicos. Se revisaron 160 casos con Diagnóstico de Apendicitis Aguda, en los años de 1999 y 2000, en el Hospital "Dr. Patrocinio Peñuela Ruíz. Se agrupo los hallazgos intraoperatorios e histopatológicos en las cuatro fases clásicas de la Apendicitis, luego se compararon los grupos por cada una de las fases. Se usó el Test de Fisher. Donde hubo mayor coincidencia fue en el grupo de apéndices sin alteraciones. En el resto se evidencia una tendencia similar a subclasificar el estado de la Apéndice macroscópicamente lo cual hace al método poco viable para establecer tratamientos.

Apendicitis aguda horas de evolución y diagnóstico histopatológico: Hospital Patrocinio Peñuela Ruíz: período 1999-2000 / Appendicitis sharp hours of evolution and diagnose histopathological: Hospital Patrocinio Peñuela Ruíz: period 1999-2000

Se estudiaron 149 casos de pacientes operados con diagnóstico histológico de apendicitis aguda, en el HPPR durante el período 1999-2000. El objetivo del mismo fue determinar la existencia o no de una correlación entre las horas de evolución y el diagnóstico histopatológico. Se recolectaron los siguientes datos de las historias clínicas: horas de evolución del dolor abdominal y diagnóstico histológico. Se clasificaron los pacientes en cuatro grupos según el tiempo de evolución del dolor (12 horas o menos, 12 a 24 horas, 24 a 48 horas). La mayor parte de los pacientes (47 por ciento) consultaron entre las 24 y 48 horas de iniciado el dolor. Para los cuatro grupos el hallazgo histológico más frecuente fue apendicitis flegmonosa y hemorrágica (46,51 por ciento, 65,51 por ciento, 55,32 por ciento y 40 por ciento respectivamente). Se concluye que no hay relación directa entre las horas de evolución del dolor y la fase histológica.