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The generation of a virtual, personal, auditory space to obtain a high-quality sound experience when using headphones is of great significance. Normally this experience is improved using personalized head-related transfer functions (HRTFs) that depend on a large degree of personal anthropometric information on pinnae. Most of the studies focus their personal auditory optimization analysis on the study of amplitude versus frequency on HRTFs, mainly in the search for significant elevation cues of frequency maps. Therefore, knowing the HRTFs of each individual is of considerable help to improve sound quality. The following work proposes a methodology to model HRTFs according to the individual structure of pinnae using multilayer perceptron and linear regression techniques. It is proposed to generate several models that allow knowing HRTFs amplitude for each frequency based on the personal anthropometric data on pinnae, the azimuth angle, and the elevation of the sound source, thus predicting frequency magnitudes. Experiments show that the prediction of new personal HRTF generates low errors, thus this model can be applied to new heads with different pinnae characteristics with high confidence. Improving the results obtained with the standard KEMAR pinna, usually used in cases where there is a lack of information.

In this study, a novel Chromium steel grade (COIN2) is produced as a result of a new steel composition and an innovative heat treatment. This new steel grade COIN2 evolves from the P92 steel grade and other novel steel grade recently created by the authors (COIN), and represents an enhancement of hardness, tensile properties, and creep behaviour with respect to them, which validates the metallurgical strategy used for further research in order to increase the efficiency of power plants and thus reduce the CO _2 emissions. The characterization reveals a significant property improvement with the innovative thermal treatment, contributing to the production of a novel and more competitive steel grade for creep applications.

INTRODUCCIÓN. La idea fundamental que subyace en nuestro proyecto es considerar la experiencia como fuente de conocimiento válido para el desarrollo de las competencias del alumnado, así como clave en los procesos reflexivos que se llevan a cabo durante el Trabajo Fin de Grado (TFG) en el Grado de Educación Social. De dicha experiencia emanan las inquietudes respecto a una situación social o educativa para llegar a problematizarla con el fin de transformarla. A ese proceso lo denominamos reflexión sentida, y las bases teóricas de nuestro proyecto se fundamentan en la filosofía de lo implícito. MÉTODO. Hemos desarrollado herramientas basadas en el aprendizaje por indagación para llevar a cabo el proceso de realización del TFG. Asimismo, utilizamos herramientas cualitativas para la obtención de los resultados. RESULTADOS. Los datos recogidos han permitido extraer resultados significativos respecto a la relevancia de la propia experiencia del alumnado, así como de las sensaciones corporales en procesos reflexivos. DISCUSIÓN. Es relevante crear nuevas herramientas para indagar en la experiencia del alumnado de cara a generar procesos de aprendizaje desde el no saber.

In the last decades, low-density steels for forging have increasing interest in the automotive industry, and good mechanical properties are required for their real application. This paper describes the results obtained for a 0.66C11.4Mn9.9Al duplex austenitic low-density steel after applying a set of isothermal treatments at different combinations of time and temperature, aimed to promote kappa carbide precipitation, and improve the mechanical properties obtained with a water quenching treatment. The effects of the different isothermal treatments on the microstructure and on the mechanical properties have been analyzed and compared to those obtained from a quenching heat treatment. We found that isothermal treatments in the range temperature between 550–750 °C promoted the profuse precipitation of coarse kappa carbides at grain boundaries, which dramatically reduced the ductility of the alloy, whereas a traditional quenching treatment resulted in a better combination of ductility and mechanical strength.

The effects of deep cryogenic treatment (DCT) on the wear behavior of different tool steels have been widely reported in the scientific literature with uneven results. Some tool steels show a significant improvement in their wear resistance when they have been cryogenically treated while others exhibit no relevant amelioration or even a reduction in their wear resistance. In this study, the influence of DCT was investigated for a grade that has been barely studied in the scientific literature, the AISI A8 air-hardening medium-alloy cold work tool steel. Several aspects were analyzed in the present work: the wear resistance of the alloy, the internal residual stress, and finally the secondary carbide precipitation in terms of lengths and occupied area and its distribution into the microstructure. The results revealed a reduction in the wear rate of about 14% when the AISI A8 was cryogenically treated before tempering. The number of carbides that precipitated into the microstructure was 6% higher for the cryogenically treated samples, increasing from 0.68% to 0.73% of the total area they covered. Furthermore, the distribution of the carbides into the microstructure was more homogenous for the cryogenically treated samples.

Juan Bautista Agirre Elola euskal idazleak, 1819an, azken testamentu olografoan Zarauzko Frantziskotarren liburutegira destinatu zituen bere liburuak, Juan Inazio Larrondobuno ilobaren medioz. Liburu horien ibilbideari jarraitu natzaio, Asteasutik 1823an abiatu, ilobak berak Mutrikun liburutegi hori gozatu ea 1868 urtean Zarauzko Frantziskotarren liburutegira iritsi arte. Liburu horien inbentarioa, sailkapena eta zenbait iruzkin egin ondoren, behin-behineko ondorio batzuetara iritsi naiz Juan Bautista Agirre Elolaren hainbat donaini buruz.

Background: Breast cancer is the most common cancer in women worldwide and is the leading cause of death amongst women with cancer. One novel therapy used for breast cancer treatment constitutes non-contact electric fields and is called electro-capacitive cancer therapy (ECCT) with intermediate frequency and low intensity. The objective of this study was to examine the effect of ECCT on mammary tumors growth in rats and observing the immune responses that play a role in fighting the tumor. Methods: Female SD rats were used and divided into four groups, namely control (NINT), placebo (NIT), non- therapy (INT), and therapy (IT) groups with 6 biological replicates in each group. Rats in INT and IT groups were treated with 7,12-dimethylbenz[a]anthracene for mammary tumor induction. Only rats in NIT and IT groups were exposed to ECCT individually for 10 hours per day for 21 days. The size of all tumors was measured with a digital caliper. The distributions of PCNA, ErbB2, caspase-3, CD68, CD4, and CD8-positive cells were observed with immunohistochemistry and scoring with ImageJ. Results: The growth rate of mammary tumors in IT group was significantly lower (p<0.05) than that in INT group. The number of mitotic figures and the percentage of PCNA, caspase-3, and CD68-positive cells in IT group were significantly lower (p<0.05) than those in INT group. Conversely, the percentage of CD8-positive T cells in IT group was significantly higher (p<0.05) than that in INT group. Moreover, the CD4/CD8 ratio in IT group was found to have decreased. Some tumor tissues were blackened and detached from the surrounding tissue, resulting in an open wound which then healed upon exposure. Conclusions: Non-contact electric fields exposure showed inhibition on mammary tumor growth in rats while inducing CD8+ T cells, leading to tumor cell death and potentially helping wounds heal., Competing Interests: No competing interests were disclosed., (Copyright: © 2021 Alamsyah F et al.)

Nanophotonics, and more specifically plasmonics, provides a rich toolbox for biomolecular sensing, since the engineered metasurfaces can enhance light-matter interactions to unprecedented levels. So far, biosensing associated with high-quality factor plasmonic resonances has almost exclusively relied on detection of spectral shifts and their associated intensity changes. However, the phase response of the plasmonic resonances have rarely been exploited, mainly because this requires a more sophisticated optical arrangement. Here we present a new phase-sensitive platform for high-throughput and label-free biosensing enhanced by plasmonics. It employs specifically designed Au nanohole arrays and a large field-of-view interferometric lens-free imaging reader operating in a collinear optical path configuration. This unique combination allows the detection of atomically thin (angstrom-level) topographical features over large areas, enabling simultaneous reading of thousands of microarray elements. As the plasmonic chips are fabricated using scalable techniques and the imaging reader is built with low-cost off-the-shelf consumer electronic and optical components, the proposed platform is ideal for point-of-care ultrasensitive biomarker detection from small sample volumes. Our research opens new horizons for on-site disease diagnostics and remote health monitoring., Competing Interests: The authors declare no conflict of interest.

Light microscopes can detect objects through several physical processes, such as scattering, absorption, and reflection. In transparent objects, these mechanisms are often too weak, and interference effects are more suitable to observe the tiny refractive index variations that produce phase shifts. We propose an on-chip microscope design that exploits birefringence in an unconventional geometry. It makes use of two sheared and quasi-overlapped illuminating beams experiencing relative phase shifts when going through the object, and a complementary metal-oxide-semiconductor image sensor array to record the resulting interference pattern. Unlike conventional microscopes, the beams are unfocused, leading to a very large field of view (20 mm(2)) and detection volume (more than 0.5 cm(3)), at the expense of lateral resolution. The high axial sensitivity (<1 nm) achieved using a novel phase-shifting interferometric operation makes the proposed device ideal for examining transparent substrates and reading microarrays of biomarkers. This is demonstrated by detecting nanometer-thick surface modulations on glass and single and double protein layers.

In this Letter, we present a method to prepare a mixed electron-beam resist composed of a positive resist (ZEP520A) and C60 fullerene. The addition of C60 to the ZEP resist changes the material properties under electron beam exposure significantly. An improvement in the thermal resistance of the mixed material has been demonstrated by fabricating multimode interference couplers and coupling regions of microring resonators. The fabrication of distributed Bragg reflector structures has shown improvement in terms of pattern definition accuracy with respect to the same structures fabricated with normal ZEP resist. Straight InP membrane waveguides with different lengths have been fabricated using this mixed resist. A decrease of the propagation loss from 6.6 to 3.3  dB/cm has been demonstrated.

Heating of irradiated metallic e-beam generated nanostructures was quantified through direct measurements paralleled by novel model-based numerical calculations. By comparing discs, triangles, and stars we showed how particle shape and composition determines the heating. Importantly, our results revealed that substantial heat is generated in the titanium adhesive layer between gold and glass. Even when the Ti layer is as thin as 2 nm it absorbs as much as a 30 nm Au layer and hence should not be ignored.

An ultrasmall (<10  μm length) polarization converter in InP membrane is fabricated and characterized. The device relies on the beating between the two eigenmodes of chemically etched triangular waveguides. Measurements show a very high polarization conversion efficiency of >99% with insertion losses of <-1.2  dB at a wavelength of 1.53 μm. Furthermore, our design is found to be broadband and tolerant to dimension variations.

We define a new general framework, the family of (psi,p,q)-vulnerabilities, as a tool that produces many new vulnerability functions that measure the capacity of a network to maintain its functional performance under random damages or malicious attacks. This new framework comprises most of the vulnerability definitions appearing in the literature and allows to calculate some relationships between the different (psi,p,q)-vulnerabilities in terms of their function psi or their parameters p, q that improve several known results for the vulnerability functions. Some graphics of simulations are provided in order to show the sharpness of these relationships.