Sticky grains do not change the universality class of isotropic sandpiles

We revisit the sandpile model with ``sticky'' grains introduced by Mohanty and Dhar [Phys. Rev. Lett. {\bf 89}, 104303 (2002)] whose scaling properties were claimed to be in the universality class of directed percolation for both isotropic and directed models. Simulations in the so-called fixed-energy ensemble show that this conclusion is not valid for isotropic sandpiles and that this model shares the same critical properties of other stochastic sandpiles, such as the Manna model. %as expected from the existence of an extra %conservation-law, absent in directed percolation. These results are strengthened by the analysis of the Langevin equations proposed by the same authors to account for this problem which we show to converge, upon coarse-graining, to the well-established set of Langevin equations for the Manna class. Therefore, the presence of a conservation law keeps isotropic sandpiles, with or without stickiness, away from the directed percolation class.Comment: 4 pages. 3 Figures. Subm. to PR

Tissue distribution of mercury and its relationship with selenium in atlantic bluefin tuna (Thunnus thynnus l.)

Mercury (Hg) is an important heavy metal to consider in marine predators, while selenium (Se) has a natural antagonistic effect on this metal in fish. The Atlantic bluefin tuna (ABFT, Thunnus thynnus) is a pelagic top-level predator of the trophic web and their Hg muscular content is an object of concern in food safety. Nevertheless, little is known about levels of this metal in remaining tissues, which may be important as by-product source, and its relationship with Se. Thus, concentration of both elements in liver, kidney, brain, gill and bone, in addition to muscle, of ABFT were determined. The kidney was the tissue with the highest concentration of Hg (Total-Hg, THg) and Se, and the Se/THg concentration ratio was similar in all tissues, except bone and muscle. The Selenium Health Benefit Value (HBVSe ) was positive in each specimen and tissue, indicating that the Se plays an important role against Hg not only in the muscle. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Preprin

Low-loss inverted taper edge coupler in silicon nitride

"This paper is a postprint of a paper submitted to and accepted for publication in IET Optoelectronics and is subject to Institution of Engineering and Technology Copyright. The copy of record is available at IET Digital Library"[EN] An inverted lateral taper with one vertical discrete step was designed for a medium confinement silicon nitride waveguide platform in the C-band, as a chip edge coupler, with a predicted insertion loss of 0.58¿dB. The design is supported by an extensive study to evaluate the impact of fabrication process variations on the performance of such a coupler. The device was manufactured and measured, showing an insertion loss of 1.47 dB, which was traced back to fabrication process variations as cross-checked with simulations. To the authors¿ knowledge, the reported edge coupler is the shortest and among the best performing found for silicon nitride platforms.The authors acknowledge financial support through projects TEC2015-69787-REDT PIC4TB, TEC2016-80385-P SINXPECT, TEC2014-54449-C3-1-R, GVA PROMETEO 2017/103, EC H2020-ICT-27-2015 PICs4all CSA 68777.Fernández-Vicente, J.; Baños Lopez, R.; Doménech Gómez, JD.; Domínguez-Horna, C.; Muñoz Muñoz, P. (2019). Low-loss inverted taper edge coupler in silicon nitride. IET Optoelectronics. 13(2):62-66. https://doi.org/10.1049/iet-opt.2018.5065S6266132Marcatili, E. A. J. (1969). Dielectric Rectangular Waveguide and Directional Coupler for Integrated Optics. Bell System Technical Journal, 48(7), 2071-2102. doi:10.1002/j.1538-7305.1969.tb01166.xMiller, S. E. (1969). Integrated Optics: An Introduction. Bell System Technical Journal, 48(7), 2059-2069. doi:10.1002/j.1538-7305.1969.tb01165.xTomlinson, W. J., & Brackett, C. A. (1987). Telecommunications applications of integrated optics and optoelectronics. Proceedings of the IEEE, 75(11), 1512-1523. doi:10.1109/proc.1987.13912Lim, A. E.-J., Junfeng Song, Qing Fang, Chao Li, Xiaoguang Tu, Ning Duan, … Tsung-Yang Liow. (2014). Review of Silicon Photonics Foundry Efforts. IEEE Journal of Selected Topics in Quantum Electronics, 20(4), 405-416. doi:10.1109/jstqe.2013.2293274Smit, M., Leijtens, X., Ambrosius, H., Bente, E., van der Tol, J., Smalbrugge, B., … van Veldhoven, R. (2014). An introduction to InP-based generic integration technology. Semiconductor Science and Technology, 29(8), 083001. doi:10.1088/0268-1242/29/8/083001Taillaert, D., Bogaerts, W., Bienstman, P., Krauss, T. F., Van Daele, P., Moerman, I., … Baets, R. (2002). An out-of-plane grating coupler for efficient butt-coupling between compact planar waveguides and single-mode fibers. IEEE Journal of Quantum Electronics, 38(7), 949-955. doi:10.1109/jqe.2002.1017613Dillon, T., Murakowski, J., Shi, S., & Prather, D. (2008). Fiber-to-waveguide coupler based on the parabolic reflector. Optics Letters, 33(9), 896. doi:10.1364/ol.33.000896Li, H., Cao, Z., Lu, H., & Shen, Q. (2003). Free-space coupling of a light beam into a symmetrical metal-cladding optical waveguide. Applied Physics Letters, 83(14), 2757-2759. doi:10.1063/1.1616205Cardenas, J., Poitras, C. B., Luke, K., Luo, L.-W., Morton, P. A., & Lipson, M. (2014). High Coupling Efficiency Etched Facet Tapers in Silicon Waveguides. IEEE Photonics Technology Letters, 26(23), 2380-2382. doi:10.1109/lpt.2014.2357177Shiraishi, K., Yoda, H., Ohshima, A., Ikedo, H., & Tsai, C. S. (2007). A silicon-based spot-size converter between single-mode fibers and Si-wire waveguides using cascaded tapers. Applied Physics Letters, 91(14), 141120. doi:10.1063/1.2795337Tao, H., Song, J., Fang, Q., Yu, M., Lo, G., & Kwong, D. (2008). Improving coupling efficiency of fiber-waveguide coupling with a double-tip coupler. Optics Express, 16(25), 20803. doi:10.1364/oe.16.020803Muñoz, P., Micó, G., Bru, L., Pastor, D., Pérez, D., Doménech, J., … Domínguez, C. (2017). Silicon Nitride Photonic Integration Platforms for Visible, Near-Infrared and Mid-Infrared Applications. Sensors, 17(9), 2088. doi:10.3390/s17092088Papes, M., Cheben, P., Benedikovic, D., Schmid, J. H., Pond, J., Halir, R., … Vašinek, V. (2016). Fiber-chip edge coupler with large mode size for silicon photonic wire waveguides. Optics Express, 24(5), 5026. doi:10.1364/oe.24.005026Cheben, P., Schmid, J. H., Wang, S., Xu, D.-X., Vachon, M., Janz, S., … Picard, M.-J. (2015). Broadband polarization independent nanophotonic coupler for silicon waveguides with ultra-high efficiency. Optics Express, 23(17), 22553. doi:10.1364/oe.23.022553Shani, Y., Henry, C. H., Kistler, R. C., Orlowsky, K. J., & Ackerman, D. A. (1989). Efficient coupling of a semiconductor laser to an optical fiber by means of a tapered waveguide on silicon. Applied Physics Letters, 55(23), 2389-2391. doi:10.1063/1.102290Zhuang, L., Marpaung, D., Burla, M., Beeker, W., Leinse, A., & Roeloffzen, C. (2011). Low-loss, high-index-contrast Si_3N_4/SiO_2 optical waveguides for optical delay lines in microwave photonics signal processing. Optics Express, 19(23), 23162. doi:10.1364/oe.19.02316

A European perspective on nosocomial urinary tract infections II. Report on incidence, clinical characteristics and outcome (ESGINI–04 study)

ObjectivesTo estimate the incidence of nosocomially acquired urinary tract infections (NAUTI) in Europe and provide information on the clinical characteristics, underlying conditions, etiology, management and outcome of patients.Materials and methodsWe collected clinical information from NAUTI patients with a microbiology report on the named study day.ResultsA total of 141 hospitals from 25 European countries participated in the study. Written institutional bladder catheter guidelines were in place in 90.3% of EU hospitals and 55% of non-EU hospitals (P <0.05). The total number of new NAUTI episodes on the day of the study was 298, representing an incidence of 3.55 episodes/1000 patient-days and an estimated prevalence of 10.65/1000. The five most commonly isolated micro-organisms were Escherichia coli, Enterococcus sp., Candida sp., Klebsiella sp. and Pseudomonas aeruginosa. Patients from non-EU countries were younger, with more severe underlying diseases with a higher incidence of obstructive uropathy/lithiasis. Overall, 22.8% of patients had no ‘classic’ UTI-predisposing factors. Catheter-associated UTI (CAUTI) was present in 187 patients (62.8%). A closed drainage system was used in only 78.5% of catheterised patients. The indication for bladder catheterisation was not considered adequate in 7.6% of cases and continuation of bladder catheterisation was considered unnecessary in 31.3%. Opening of the closed drainage system was the most frequent major error in catheter management (16.8%). Antimicrobial treatment was not considered adequate in 19.8% of all cases.ConclusionsThe incidence of NAUTI in a large European population is 3.55/1000 patient-days. There is clearly room for improvement in the area of bladder catheterisation, catheter care and medical management of NAUTI. We recommend that European authorities draw up and implement practical and specific guidelines to reduce the incidence of this infection

Review of Wind Models at a Local Scale: Advantages and Disadvantages

Wind forecasts are widely spread because of the growth in wind power, but also because there are other applications to consider, such as the long-term scenario forecasts regarding the effects of global warming. Overall, there have been big developments in global circulation models (GCM) that inform future scenarios at the large scale, but wind forecast at a local scale is a problem that has not totally been solved. It should be possible to estimate the winds in the near field with a certain accuracy, which is interesting for aspects such as the blowing of incident wind at wind farms, the wind on a dune in movement, or the wind blowing in a harbour. Therefore, a data-driven wind transference equation at a local scale is needed. Among the conclusions, it is worthy to state that the statistical downscaling techniques are suitable for application as a statistical inference at small scales. The aim of this paper is therefore to review the current methods and techniques used and show the different methodologies and their applications in the field. Additional targets will be to identify the advantages, disadvantages, or limitations of the current models at the local scale and propose research to find possible improvements

Polynomial Inequalities on the π/4-Circle Sector

A number of sharp inequalities are proved for the space P (2D (π/4)) of 2-homogeneous polynomials on ℝ2 endowed with the supremum norm on the sector D (π/4) := {eiθ : θ ∈ [0, π/4]}. Among the main results we can find sharp Bernstein and Markov inequalities and the calculation of the polarization constant and the unconditional constant of the canonical basis of the space P (2D (π/4))

Experimental study of R1234yf as a drop-in replacement for R134a in a domestic refrigerator

This paper presents an experimental study for three identical domestic refrigerators using R1234yf as a drop-in replacement for R134a. An alternative methodology was proposed to estimate the optimal mass charge for R1234yf; with the use of such methodology, new evidences were sought on the thermal behavior of the refrigerator compartments as well as at the heat exchangers. Additionally, energy performance for both refrigerants was measured, and, finally, a TEWI analysis was conducted. For the type of refrigerator evaluated, results showed that R1234yf presented an average (for the 3 refrigerators) of 0.4 °C for the fresh food compartment, and 1.2 °C for the freezer, among different charges with respect to R134a. The optimal charge for R1234yf was 92.2 g, which is about 7.8% lower than the one for R134a, which represents a small increase of 4% in energy consumption in comparison to R134a. Finally, the TEWI analysis for the R1234yf was 1.07% higher than the R134a.We thank Universidad de Guanajuato for the support in the realization of this research. We also want to thank the Company Honeywell (through Marco García) for the donation of the refrigerant R1234yf, and to acknowledge the support of Mabe TyP in the performing of the tests. The authors wish to thank to Montoro Sanjosé Carlos Rubín for their support in the editing of the English-language version of this paper

A new species of Enyalioides (Iguanidae: Hoplocercinae) from southwestern Ecuador

We describe a new species of Enyalioides from lowland cloud forests in southwestern Ecuador. This represents the third species in the genus known to occur west of the Andes in South America; the other two species are E. heterolepis and E. oshaughnessyi. Among other characters, the new species can be distinguished from other members in the genus by having small, keeled, paravertebrals; a series of skin folds on the lateral aspects of body and neck; size-homogeneous scales on body and limbs; distinct caudal segments; and an extensive dark patch on the gular region of adult males. Morphological similarity suggests that the new species, which we call E. touzeti, is closely related to E. oshaughnessyi.Describimos una especie nueva de Enyalioides del bosque nublado al suroccidente de Ecuador. Esta representa la tercera especie de este género que habita al occidente de los Andes en América del Sur; las otras dos especies occidentales son E. heterolepis y E. oshaughnessyi. La especie nueva se diferencia de otras especies del género por tener, entre otras características, paravertebrales pequeñas y quilladas, pliegues dermales a los lados del cuello y cuerpo, escamas homogéneas en el cuerpo y extremidades, segmentos caudales visibles, y un parche oscuro que cubre gran parte de la región gular en machos. Semejanzas morfológicas sugieren que la especie nueva, a la cual llamamos E. touzeti, está cercanamente relacionada con E. oshaughnessyi

Real-time detection of uncalibrated sensors using Neural Networks

Nowadays, sensors play a major role in several contexts like science, industry and daily life which benefit of their use. However, the retrieved information must be reliable. Anomalies in the behavior of sensors can give rise to critical consequences such as ruining a scientific project or jeopardizing the quality of the production in industrial production lines. One of the more subtle kind of anomalies are uncalibrations. An uncalibration is said to take place when the sensor is not adjusted or standardized by calibration according to a ground truth value. In this work, an online machine-learning based uncalibration detector for temperature, humidity and pressure sensors was developed. This solution integrates an Artificial Neural Network as main component which learns from the behavior of the sensors under calibrated conditions. Then, after trained and deployed, it detects uncalibrations once they take place. The obtained results show that the proposed solution is able to detect uncalibrations for deviation values of 0.25 degrees, 1% RH and 1.5 Pa, respectively. This solution can be adapted to different contexts by means of transfer learning, whose application allows for the addition of new sensors, the deployment into new environments and the retraining of the model with minimum amounts of data

Learning Buckets: Helping Teachers Introduce Flexibility in the Management of Learning Artifacts Across Spaces

Producción Científicaechnology offers rich opportunities for learning across different physical and virtual spaces. However, most of current across-spaces proposals are either highly teacher-centered, inflexible in the students’ self-management of learning artifacts during the enactment, or allow the teacher little/no control of such students’ management of artifacts. Moreover, these proposals tend to be disconnected from the practices and tools that are usual in the classroom. How can we achieve a middle ground between keeping the teacher in control of across-spaces situations and, at the same time, providing students with a degree of flexibility to manage learning artifacts? Aiming to address such challenge we propose the notion of learning bucket, and the Bucket-Server, a system implementing such notion. A learning bucket is a container of learning artifacts which are generated and/or accessed across-spaces by the students during the enactment, according to constraints configured by teachers at design time. The responsive evaluation conducted, based on a feature analysis and a pilot study with experts, suggests that learning buckets can help evolve from teacher- to student-centered approaches, while maintaining the teacher in control of students’ actions. The evaluation also indicates that the Bucket-Server surpasses the support provided by alternative proposals to across-spaces learning.Ministerio de Economía, Industria y Competitividad (Project TIN2014- 53199-C3-2- R)Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA277U14