Ultrafast Laser Inscription of Buried Waveguides in W-TCP Bioactive Eutectic Glasses

Since the first report of Davis in 1996, ultrafast laser inscription (ULI) has been widely used to fabricate buried optical devices such as active and passive waveguides inside dielectric materials. In this technique, ultra-short and ultra-intense laser pulses are tightly focused inside transparent materials leading to laser-induced nonlinear processes in the focal volume. The energy density deposited into the submicron focal volume can reach several of MJcm−3 and hence, may trigger dramatic changes in a strongly localized region, whereas the surrounding bulk material remains unchanged. This technique can be used from void formation to weak refractive index modification, which is the key feature to create buried optical waveguides. In this chapter, firstly, we review the fundamentals of the ultrafast laser inscription technique to produce optical waveguides inside dielectric materials such as crystals and glasses. Next, as an example, we revise the application of this technique to create buried waveguides inside bioactive glasses and specifically, inside W-TCP eutectic glasses

Potenciales evocados cerebrales en el contexto de la investigación psicológica: una actualización

Event-related brain potentials (ERPS) are presented in the context of the psychological research. Firstly, aspects such as how un ERP is obtained, their characteristic features, the way in which they are classified, or their main advantages with respect to another type of measures usually used in Psychology, are presented. Then, two cognitive processes that have been extensively investigated with this technique are briejly reviewed, concretely, attention and language, and the recent research in the study of emotional processes is also commented. The main ERPs that have been used to study these psychological processes are discussed

Actividades enzimáticas en Basidiomicetos formadores de ectomicorrizas en Pinus radiata D. Don.

La reproducción de enzimas extracelulares por las ectomicorrizas moviliza una fracción importante de los compuestos presentes en el suelo. Se presentan resultados de las actividades enzimáticas relacionadas con la movilización de nitrógeno y fósforo para cuatro especies de hongos formadores de ectomicorrizas, Suillus luteus (L.: Fr.) F. Gray, Xerocomus badius (Fr.:Fr.) Gilbert, Boletus pinicola (Vitt.) Venturi y Pisolithus tinctorius (Pers.) Coker & Couch. Se considera el valor potencial de las actividades enzimáticas como criterio en la selección de hongos inoculantes. Los valores altos suponen una mayor utilidad de los hongos corno inoculantes en condiciones de vivero.Extracellular enzyme production by ectomycorrhizae is able to movilize an important soil fraction. We report enzyme activities related with nitrogen and phosphorus movi I ization in four ectomycorriza-forming fungi: Suillus luteus (L.: Fr.) F. Gray, Xerocomus badius (Fr.:Fr.) Gilbert, Boletus pinicola (Vitt.) Venturi andPisolithus tinctorius (Pers.) Coker & Couch We examine the potential value of enzyme activity as a criterion for selecting inoculant fungi. High values are considered as profitable for inoculants under nursery conditions

Multivariate Radiological-Based Models for the Prediction of Future Knee Pain: Data from the OAI

In this work, the potential of X-ray based multivariate prognostic models to predict the onset of chronic knee pain is presented. Using X-rays quantitative image assessments of joint-space-width (JSW) and paired semiquantitative central X-ray scores from the Osteoarthritis Initiative (OAI), a case-control study is presented. The pain assessments of the right knee at the baseline and the 60-month visits were used to screen for case/control subjects. Scores were analyzed at the time of pain incidence (T-0), the year prior incidence (T-1), and two years before pain incidence (T-2). Multivariate models were created by a cross validated elastic-net regularized generalized linear models feature selection tool. Univariate differences between cases and controls were reported by AUC, C-statistics, and ODDs ratios. Univariate analysis indicated that the medial osteophytes were significantly more prevalent in cases than controls: C-stat 0.62, 0.62, and 0.61, at T-0, T-1, and T-2, respectively. The multivariate JSW models significantly predicted pain: AUC = 0.695, 0.623, and 0.620, at T-0, T-1, and T-2, respectively. Semiquantitative multivariate models predicted paint with C-stat = 0.671, 0.648, and 0.645 at T-0, T-1, and T-2, respectively. Multivariate models derived from plain X-ray radiography assessments may be used to predict subjects that are at risk of developing knee pain

Directionally solidified cobalt-doped MgO-MgAl2O4 eutectic composites for selective emitters

Cobalt-doped MgO-MgAl2O4 eutectic composites were explored for their use as selective emitters for thermophotovoltaic devices. Eutectic ceramic rods with different cobalt content were directionally solidified by using the laser floating zone technique at two processing rates to obtain microstructures with different domain sizes. Thermal emission between 1000 °C and 1500 °C and optical properties (reflectance and transmittance) at room temperature were measured in the Co-doped composites and the effect on microstructure and cobalt content was investigated. Thermal emission consisted of an intense broad band at about 1.67 µm matching with the bandgap of the InGaAs cell. The emission was ascribed to the de-excitation from the 4T1(F) multiplet to the 4A2(F) ground state of the thermally excited Co ions located in the tetrahedral sites of the MgAl2O4 phase. The selectivity of the thermal emission showed a decrease with the cobalt content due to the enhancement of other electronic transitions, which leads to keeping the cobalt content in these composites at low levels (<0.15% at Co) for their use as selective emitters

Evaluation of resampling applied to UAV imagery for weed detection using OBIA

Los vehículos aéreos no tripulados (UAVs) son una tecnología emergente en el estudio de parámetros agrícolas por sus características y por portar sensores en diferente rango espectral. En este trabajo se ha detectado y cartografiado rodales de malas hierbas en fase temprana mediante análisis OBIA para elaborar mapas que optimicen el tratamiento herbicida localizado. Se ha aplicado resampling (resampleo) sobre imágenes tomadas en campo desde un UAV (UAV-I) para crear una nueva imagen con distinta resolución espacial. A las imágenes resampleadas (RS-I) se les evaluó la calidad espacial y espectral y la eficacia de nuestro análisis en la detección de malas hierbas. Los resultados de las imágenes RS-I muestran una precisión similar a las imágenes UAV-I siendo factible su utilización en tecnologías de manejo localizado de malas hierbas. Se discuten las ventajas del uso de la técnica de resampling en imágenes UAV.Unmanned aerial vehicles (UAV) are an emerging technology for the study of agriculture parameters due to its characteristics and the availability of embedding sensors with different spectral range. In our study, the detection and mapping of weeds in early phenological stage allowed to design a strategy for the optimizing of herbicide treatment. In this work, resampling is used to create a new version of an image with a different spatial resolution, using real UAV imagery. A spatial and spectral quality evaluation was carried out to resampled images (RS-I), and then, our workflow for weed detection applied. The results showed that RS-I and UAV-I showed similar accuracy on weed detection and thus could be used for site-specific weed management achieving a percentage of savings in the herbicide. Opportunities of using RS-I are discussed

Elusive super-hard B6C accessible through the laser-floating zone method

Boron carbide is among the most promising ceramic materials nowadays: their mechanical properties are outstanding, and they open potential critical applications in near future. Since sinterability is the most critical drawback to this goal, innovative and competitive sintering procedures are attractive research topics in the science and technology of this carbide. This work reports the pioneer use of the laser-floating zone technique with this carbide. Crystallographic, microstructural and mechanical characterization of the so-prepared samples is carefully analysed. One unexpected output is the fabrication of a B6C composite when critical conditions of growth rate are adopted. Since this is one of the hardest materials in Nature and it is achievable only under extremely high pressures and temperatures in hot-pressing, the use of this technique offers a promising alternative for the fabrication. Hardness and elastic modulus of this material reached to 52¿GPa and 600¿GPa respectively, which is close to theoretical predictions reported in literature

Boosting precision crop protection towards agriculture 5.0 via machine learning and emerging technologies: A contextual review

Crop protection is a key activity for the sustainability and feasibility of agriculture in a current context of climate change, which is causing the destabilization of agricultural practices and an increase in the incidence of current or invasive pests, and a growing world population that requires guaranteeing the food supply chain and ensuring food security. In view of these events, this article provides a contextual review in six sections on the role of artificial intelligence (AI), machine learning (ML) and other emerging technologies to solve current and future challenges of crop protection. Over time, crop protection has progressed from a primitive agriculture 1.0 (Ag1.0) through various technological developments to reach a level of maturity closelyin line with Ag5.0 (section 1), which is characterized by successfully leveraging ML capacity and modern agricultural devices and machines that perceive, analyze and actuate following the main stages of precision crop protection (section 2). Section 3 presents a taxonomy of ML algorithms that support the development and implementation of precision crop protection, while section 4 analyses the scientific impact of ML on the basis of an extensive bibliometric study of >120 algorithms, outlining the most widely used ML and deep learning (DL) techniques currently applied in relevant case studies on the detection and control of crop diseases, weeds and plagues. Section 5 describes 39 emerging technologies in the fields of smart sensors and other advanced hardware devices, telecommunications, proximal and remote sensing, and AI-based robotics that will foreseeably lead the next generation of perception-based, decision-making and actuation systems for digitized, smart and real-time crop protection in a realistic Ag5.0. Finally, section 6 highlights the main conclusions and final remarks

Chemical and Physical Implications of the Use of Alternative Vessels to Oak Barrels during the Production of White Wines

Recently, the use of alternative vessels to oak barrels during winemaking has become increasingly popular, but little is known about their impact on the chemical composition of the resulting wines. To address this issue, a Sauvignon Blanc wine was elaborated from the same grape juice by using cylindrical stainless-steel tanks, oval-shaped concrete vessels, oval-shaped polyethylene vessels, and clay jars in triplicate. Each vessel was used for alcoholic fermentation and the aging of wines over its own lees. Wines elaborated in concrete vessels showed the highest pH and the lowest titratable acidity, most likely related to the observed release of inorganic compounds from the concrete walls. Little effect of the vessels was seen on the wine color and phenolic composition. Wines elaborated in clay jars showed the highest turbidity and the highest content of soluble polysaccharides, while those made using cylindrical stainless-steel tanks showed the highest content of volatile compounds. Despite the observed differences, all of the vessels tested seem suitable for white wine production since every wine showed chemical features that corresponded with the quality standards of Sauvignon Blanc wines.España Universidad de Sevilla, VI Plan Propio de Investigación y Transferencia (Contract number USE-18644-Z