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BACKGROUND Anesthetic regimens using dexmedetomidine and short-acting opioids have been suggested as potential alternatives to sevoflurane-based anesthesia in children. The primary aim of this study is to compare demographics, intraoperative characteristics, and complications of general anesthetics in which dexmedetomidine and opioids were used without sevoflurane, or in combination with a low sevoflurane concentration, in children 36 months old and younger. The secondary aim is to evaluate intraoperative bispectral index (BIS) values when available in these patients. METHODS General anesthetics performed between January 1, 2017, and May 1, 2018, in children 2 years and younger who received dexmedetomidine and remifentanil, with or without sevoflurane, were identified. Additional anesthetics performed during this time in children 36 months and younger who received dexmedetomidine and opioids and had BIS monitoring were also identified. Charts were reviewed for demographic and intraoperative variables, including drug administration and hemodynamic data. RESULTS A total of 244 patients were identified. All but 22 patients received remifentanil. Ninety-two patients received sevoflurane with a mean end-tidal concentration of 0.84% (SD 0.43). Compared to the sevoflurane group, the nonsevoflurane group received more remifentanil (median dose 0.4 μg/kg/min vs 0.2 μg/kg/min, difference of 0.1 μg/kg/min, 95% CI 0.1-0.3, P

Surface temperature measurements of ceramic matrix composite (CMC) based engine components within the hot section of a gas turbine engines are needed to verify engine designs and cooling requirements. Traditional temperature sensors cannot be applied to silicon carbide (SiC) based CMC's for this purpose, since they cannot be welded or embedded in the material. For these reasons, a novel thermocouple was developed for surface temperature measurement of p -type SiC-SiC CMC's. This novel thermocouple uses the p -type SiC-SiC CMC itself as one of the thermoelements and indium-tin-oxide (ITO) as the other thermoelement. Since both thermoelements are wide bandgap semiconductors, this thermocouple has exceptional thermoelectric output. A thermoelectric output of 272 μV/°K was observed for this ITO:SiC CMC thermocouple, which is an order of magnitude larger than that of type- K thermocouples. A drift rate of 3.28 °C/h was measured for this ITO:SiC CMC thermocouple. In addition, indium tin oxynitride (ITON) protective coatings deposited via reactive sputtering enabled these thermocouples to operate at 1000 °C. The ITON coating served as an oxygen diffusion barrier to prevent oxidation at the ITO:SiC CMC junction. Nitrogen and air anneals at 550 and 1000 °C, respectively, were used to improve the high temperature stability of the ITO and ITON coatings. Performance, fabrication details, and challenges using these ITO:SiC CMC thermocouple are discussed within.

The emergency department (ED) diagnosis of Crohn’s disease (CD)-associated complications is typically established with abdominopelvic computed tomography imaging. Ultrasonography has been suggested as an effective alternative modality for diagnosing several CD complications, including intraabdominal abscesses. We report the identification of a CD-related intraabdominal abscess by emergency physician (EP)-performed point-of-care ultrasound (POCUS). This case highlights the feasibility of EPs integrating POCUS into the clinical decision-making for patients with inflammatory bowel disease in the ED.

As increasingly more SiCSiC ceramic matrix composites (CMCs) are being used in the hot sections of gas-turbine engines, there is a greater need for in situ strain measurement in these harsh conditions. Thin-film strain sensors are ideally suited for this task since they have minimal mass and are nonintrusive. However, if the bulk piezoresistive properties of SiCSiC CMCs could be used instead of the thin-film piezoresistive properties, superior resolution and stability could be realized. Toward this end, we have fabricated strain gages in which the active strain element is the SiCSiC CMC itself. As a result of this approach, a Pt:SiC CMC strain gage that is capable of operating at 500C for prolonged periods was demonstrated. The large piezoresistive responses associated with the SiC fibers and SiC matrix resulted in gage factors larger than 100. The performance of the Pt:SiC CMC strain gages under both tension and compression are reported, and the IV characteristics of the strain gages, as well as the piezoresistive response as a function of temperature, are presented. In addition, the potential for embedded strain gages in advanced CMC engine components will be discussed.

A platinum:silicon carbide thermocouple has been developed to measure the surface temperature of ceramic matrix composites (CMC) with high resolution. Platinum was deposited by rf sputtering onto a SiC-SiC CMC substrates coated with a dielectric, such that the SiC-SiC CMC was one thermoelement and the platinum film was another thermoelement comprising the Pt:SiC(CMC) thermocouple. The purpose of the dielectric was to electrically isolate the platinum leads from the SiC-SiC CMC. The thermoelectric output, hysteresis and drift of the Pt:SiC(CMC) thermocouples were measured at temperatures ranging from 600 °C to 1000 °C. The thermoelectric powers generated by the Pt:SiC thermocouples were an order in magnitude greater than conventional Pt:Pd or Type K thermocouples. Thermoelectric powers as large as 250 μV/K were reported for these thermocouples, as compared to thermoelectric powers of 10 μV/K reported for Pt:Pd and Type K thermocouples. The results presented within show that the Pt:SiC(CMC) thermocouples exhibit excellent stability at high temperatures, relatively low drift rates, and little hysteresis during thermal cycling. However, the Pt:SiC junctions were prone to oxidation effects as well as the formation of platinum silicides at high temperature, which can compromise the junction and lead to excessive drift. Therefore, a number of diffusion barrier coatings were applied to the Pt:SiC junctions in an attempt to improve stability and lower drift in this promising new class of thermocouples.

As more and more SiC–SiC ceramic matrix composites or CMC’s are being used in the hot sections of gas turbine engines, there is a greater need for surface temperature measurement in these harsh conditions. Thin film sensors are ideally suited for this task since they have very small thermal masses and are nonintrusive due to their thickness. However, if the bulk properties of SiC contributed to the sensor performance (thermoelectric response) rather than those of the thin films, superior resolution, and stability could be realized. Therefore, thermocouples utilizing the SiC–SiC CMC itself as one thermoelement and thin film platinum as the other thermoelement were developed. Large and stable thermoelectric powers (as large as 250 μV/°K) were realized with these Pt:SiC (CMC) thermocouples. The advantages in using this approach for surface temperature measurement are presented as well as the effects of fiber orientation on thermoelectric response and drift.

En el presente estudio se analizó el suelo de un cultivo de maíz de la ciudad de Pamplona, Norte de Santander. El objetivo de este radicó en la recuperación y análisis de las funciones que cumplen los microorganismos en los diferentes ciclos biogeoquímicos (amonificantes, nitrificantes, desnitrificantes, celulolíticos, amilolíticos y hongos antagonistas) del suelo de un cultivo de maíz localizado a 07° 23’ 20.6’’ norte y 72° 38.59’ 0’’ oeste y altitud de 2200 msnm. Se realizaron análisis físicos y químicos convencionales de: pH, humedad, densidad, capacidad de retención de agua y colorimétricos para poder establecer las condiciones propias del suelo y establecer como en función de esto se desarrollan las diferentes poblaciones microbianas y así proceder a realizar el análisis microbiológico mediante metodologías tradicionales de aislamiento, en el que se estudiaron microorganismos que intervienen en los ciclos biogeoquímicos del nitrógeno (amonificantes, nitrificantes y desnitrificantes), en el ciclo del carbono (celulíticos y amilolíticos) y posibles hongos con capacidad antagónica. Se obtuvo el recuento de una población total de 48 y 37 millones de bacterias y hongos respectivamente, donde se estimó que el 28,7% intervienen en el ciclo del nitrógeno, el 15,5% en el ciclo del carbono, aproximadamente un 55.8% de microorganismos no intervienen en ningún proceso estudiado y de 10 hongos con posible actividad antagónica: se obtuvo uno del género Penicillium spp. con capacidad de inhibir bacterias como E. coli y S.Bistua:Revista de la Facultad de Ciencias Básicas.2018.16(1):03-12aureus.Palabras clave: amonificantes, antibióticos, ci

Cope's gray tree frog Hyla chrysoscelis accumulates glycerol during cold acclimation. We hypothesized that, during this process, gray tree frogs adjust renal filtration and/or reabsorption rates to retain accumulated glycerol. During cold acclimation, plasma concentrations of glycerol rose >200-fold, to 51 mmol/l. Although fractional water reabsorption decreased, glomerular filtration rate (GFR) and, consequently, urine flow were

Energy storage and conversion mechanism are different for on lithium ion batteries (LIB) and supercapacitors (Electrical Double Layer Capacitors- EDLCs), materials that can be used for both could lead in the future the energy storage and conversion technologies. We explored a non-conventional process to synthesize SnO2/G/GO composite powder which is conformal structure was characterized under different techniques. Comprehensive analysis of the structural and chemical properties reveals that the material consists of highly dispersed SnO2 nanoparticles in G/GO matrix. The dispersed SnO2/G/GO suspension was coated an aluminum foil for the supercapacitors electrodes. We examine the electrical conductivity of the electrodes by atomic force microscope (AFM), scanning electron microscope (SEM) and transmission electron microscope (TEM). We assembled the Al coated SnO2/G/GO composite as a supercapacitor inserting one solid-state electrolyte between two electrodes, assembled into a sandwich structure. The specific capacitance and cycle-life stability of the supercapacitor was investigated by cyclic voltammetry analysis. For LIB applications, the SnO2-G/GO composite exhibited high capacity and excellent electrochemical performance as anode material. For both applications, the quantitative/qualitative results show that G/GO is providing contact areas which results in more energy density at the interface electrode/electrolyte and that the SnO2 provides additional ions to the EDL and the electrochemical process. The Overscreening phenomena observed, which is a function of ionic size, surface charge density of the electrodes, can also be a function of concentration of the electrolyte, porosity of the electrodes (G/GO) and the ions provided to the electrode/electrolyte interface by the electrode.

Through this work we report an efficient way to produce high specific capacitance in supercapacitors devices based on zeolite template and by controllable oxidation percentage of high-quality graphene oxide. We discuss the fabrication of complex hybrid nanostructures by growing carbon-compounds on pre-synthesized nanostructured zeolites templates by chemical vapor deposition (CVD) and then etching away the zeolites, controlling the oxygen percentage in the structure. We study two types of zeolites structures, NaX and NaY to explore the side effects. Systematically, all roles of different parameters were studied, such as the composition, morphology and crystallinity of the Zeolites, as well as the CVD growth temperature and different carbon precursors to grow carbon-compound on Zeolites. Furthermore, the selection of a zeolite is also important, as type X are shown to be more resistant to thermal damage than their type Y. Finally, we could successfully remove the zeolite templates to form free-standing carbon-based nanostructures. The results presented in this analysis demonstrate the long lifespan that this type of material offers to improve capacitance.

We propose a low cost and simple method to prepare carbon hybrid structure-based electrodes in this study. Hybrid-structure Carbon Nanostrures were obtained using a zeolite as a template. The resulting carbon nanostructures are mostly configured by Graphene and multiwall carbon nanotubes (G/MWCNTs). The G/MWCNTs were dispersed onto the shallow surface of alumina foil forming as the electrodes. The electrical conductivity and dispersed morphology of the G/MWCNTs -based conductive electrode were examined by atomic force microscope (AFM), scanning electron microscope (SEM) and transmission electron microscope (TEM). Using the standard method we assembled the Lithium Ion Battery in the Ar-filled glove box, we used LiPF6 with EC:DMC::1:2 ratio as the electrolyte, lithium foil as the counter electrode and G/MWCNTs material. The specific capacity and cycle-life stability of the G/MWCNTs-based lithium ion battery was investigated by cyclic voltammetry analysis.