An adaptive solver for viscoelastic incompressible two-phase problems applied to the study of the splashing of slightly viscoelastic droplets

We propose an adaptive numerical solver for the study of viscoelastic 2D two-phase flows using the volume-of-fluid method. The scheme uses the robust log conformation tensor technique of Fattal & Kupferman (2004,2005} combined with the time-split scheme proposed by Hao & Pan (2007}. The use of this time-split scheme has been proven to increase the stability of the numerical computation of two-phase flows. We show that the adaptive computational technique can be used to simulate viscoelastic flows efficiently. The solver is coded using the open-source libraries provided by the \basilisk \cite{Basilisk} platform. In particular, the method is implemented for Oldroyd-B type viscoelastic fluids and related models (FENE-P and FENE-CR). The numerical scheme is then used to study the splashing of weakly viscoelastic drops. The solvers and tests of this work are freely available on the Basilisk web sit

Magnetic Fields to Enhance Tuned Liquid Damper Performance for Vibration Control: A Review

Tuned Liquid Dampers (TLDs) are dissipative devices whose distinguished features like low cost in installation and maintenance or their multidirectional and multifrequency application to new and already existing structures make them an attractive damping option. Their working principle is similar to that of a Tuned Mass Damper but in this case the relative movement comes from a fluid that provides with mass, damping and stiffness. Moreover, TLDs can mitigate both horizontal and vertical vibrations. All these make TLDs worth deeply studying. TLD utilization in civil vibration control arose in the 1980s. From early years, different improvements have been implemented to achieve a better performance. Some of these modifications include passive variations in the geometry or the fluid. The use of smart materials applied on TLDs has also been of great interest since the 1990s and comprehends different configurations in which magnetic fields are used to passively or semi-actively improve the TLD performance. A lack of review is detected in this field. For this reason, a state-of-the-art review is presented in this paper. Its aim is to help researchers find a thorough, up-to-date classification of the different possibilities, configurations, numerical evaluation, materials used and also found limitations and future development in the application of magnetic fields on TLDs

Wavelength converter using a highly erbium doped optical fiber ring laser

RESUMEN: En este trabajo se presenta un conversor de longitud de onda ultra-estrecho, de alta eficiencia y todo-fibra basado en el efecto de la competición de modos en un láser de fibra dopada con erbio. Se han llevado a cabo estudios experimentales con frecuencias que van desde varios kilohercios hasta las decenas de gigahercios y para más de una longitud de onda de emisión, demostrando así que este efecto puede ser utilizado para la conversión en longitud de onda de múltiples longitudes de emisión simultáneamente.ABSTRACT: This work presents an all-fiber wavelength converter based on a highly Erdoped fiber laser which has been experimentally demonstrated. Frequencies from several kilohertz up to tens of gigahertz have been investigated. Making use of the gain competition in the amplifying medium, the wavelength conversion can be carried out over not only one lasing wavelength but over several ones. These analyses have been also carried out for more than one all-fiber ring structure, demonstrating the viability of this wavelength converter.Este trabajo ha sido financiado por la Comisión Interministerial de Ciencia y Tecnología dentro de los proyectos TEC2013-47264-C2 y TEC2016-76021-C2

Razlike u razinama anti-Müllerovog hormona u krvnoj plazmi i reproduktivnih parametara između dvije vrste goveda Bos indicus i Bubalus bubalis

The aim of this study was to evaluate the possible relationships between reproductive parameters and Anti Mullerian Hormone (AMH) levels in two closely related bovine species. AMH levels and the reproductive parameters of 50 water buffaloes (Bubalus bubalis) and 50 Zebu cattle (Bos indicus) of the same age and raised in similar conditions were evaluated. Clinical data were obtained from the farm in specialized designed format, and AMH was measured by ELISA. The results show that Zebu cattle had higher AMH levels than water buffaloes (P<0.0001), while water buffaloes exhibited better reproductive parameters: days open to pregnancy (P<0.0001), parity (P<0.0005), age at first calving (P<0.0001), and intercalving period (P<0.0001). Although both species have different reproductive parameters, no correlations were found between AMH and the reproductive parameters evaluated in either species. Finally, pregnant Zebu cattle and water buffalo showed a tendency to have lower AMH levels than non-pregnant counterparts. The results are paradoxical as the species with lower AMH levels exhibited better reproductive parameters, suggesting that the reproductive parameters within the herd do not depend solely on the ovarian reserve of females.Cilj je ovog rada bio procijeniti je li moguće ustanoviti povezanost između reproduktivnih parametara i razina anti-Müllerovog hormona (AMH) u dvije blisko srodne vrste goveda. Analizirane su razine AMH i reproduktivni parametri 50 bivola (Bubalus bubalis) i 50 zebu goveda (Bos indicus) iste dobi uzgojenih u sličnim uvjetima. Klinički podatci dobiveni su s farme u posebno osmišljenom pokusu. AMH je određivan pomoću ELISA metode. Rezultati pokazuju da su razine AMH više u goveda nego u bivola (P<0,0001). Bivoli su pokazali bolje reproduktivne parametre: servisno razdoblje (P<0,0001), paritet (P<0,0005), dob kod prvog teljenja (P<0,0001) i međutelidbeno razdoblje (P<0,0001). Premda obje vrste imaju različite reproduktivne parametre, nije ustanovljena povezanost između AMH i analiziranih reproduktivnih parametara niti u jedne od istraživanih vrsta. Zaključno, steone ženke goveda i bivola pokazuju tendenciju manjih razina AMH u usporedbi s nesteonim. Rezultati dobiveni u ovoj studiji su paradoksalni, jer vrste s nižim AMH razinama pokazuju bolje reproduktivne parametre. Ovi rezultati ukazuju na to da reproduktivni parametri unutar krda ne ovise samo o rezervi jajnih stanica u ženki

Necrotic loxoscelism in lower limb and reconstruction with skin autograft

Loxesceles are small spiders, from 9 to 25 mm, with a dark brown spot on the dorsal part in the shape of an inverted violin. They are common in northwestern Mexico and can live at temperatures of 8 to 40°C. These spiders are considered of medical importance because their venom is dermonecrotic, with proteolytic and necrotic action, which is generated in two apocrine glands. The cutaneous clinical picture is the most frequent, with edema, erythema and ischemia that tends to evolve to ulceration and deep necrosis. The key to treatment is early debridement to avoid complications. We presented the case of a 57-year-old female patient who developed an inflammatory condition secondary to a fiddler spider bite involving the left lower extremity. Her evolution to necrosis and late diagnosis required surgical debridement and use of negative pressure therapy (VAC), followed by harvesting and placement of partial thickness skin autograft, obtaining a successful aesthetic and functional result

Fiber Optic Sensing System for Temperature and Gas Monitoring in Coal Waste Pile Combustion Environments

International audienceIt is presented an optical fiber sensing system projected to operate in the demanding conditions associated with coal waste piles in combustion. Distributed temperature measurement and spot gas sensing are requirements for such a system. A field prototype has been installed and is continuously gathering data, which will input a geological model of the coal waste piles in combustion aiming to understand their dynamics and evolution. Results are presented on distributed temperature and ammonia measurement, being noticed any significant methane emission in the short time period considered. Carbon dioxide is also a targeted gas for measurement, with validated results available soon. The assessment of this technology as an effective and reliable tool to address the problem of monitoring coal waste piles in combustion opens the possibility of its widespread application in view of the worldwide presence of coal related fires