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Nanoparticles made of High Refractive Index dielectric materials have been proposed as an alternative to metals driven by their low-losses and magnetic response. The coherent effects between the electric and magnetic resonances are responsible for their exceptional directionality properties that make them attractive in applications where enhancing light-matter interaction and controlling the radiation direction is extremely relevant. These nanoparticles, when used as unit-cells of more complex systems, such as metasurfaces, result to be essential in the design of novel optical devices. Their low-losses, strong confinement of electromagnetic energy and the outstanding scattering efficiencies show these nanoantennas as promising candidates for Surface Enhanced Spectroscopies, non-linear phenomena or sensing. Here, we describe and discuss the origins and recent advances in this rapidly developing field of dielectric nanophotonics, paying special attention to the main significant contributions we have done since its startup to boost its progress. In particular, light directivity, steering and switching of light, spectroscopy, sensing and non-linear phenomena, third harmonic generation are some of the applications that motivated this brief overview. [ABSTRACT FROM AUTHOR]

The occurrence of arsenic is frequently observed in groundwaters around the world and harshly affects several million people. Although different technologies have been proven to be efficient to face this environmental threat, adsorption with functionalized magnetic nanomaterials is one of the best alternatives, due to its flexibility and efficient energy use. However, the presence of competing ions typically found in natural waters might affect the arsenic removal efficacy. This paper reports the effect of the presence of carbonate, sulphate, nitrate, silicate, phosphate, chloride, fluoride and iron ions on the arsenate adsorption onto magnetic SiO 2 /Fe 3 O 4 functionalized with aminoalkoxysilane groups incorporating Fe 3+ . The adsorption equilibrium of arsenate in the concentration range 50–1000 μg L −1 was satisfactorily described by linear isotherms with values of the equilibrium parameter K H ,298K = 278.8 L g −1 in monocomponent systems and K H ,298K = 1.80 L g −1 in the presence of competing ions. Carbonate and especially phosphate are demonstrated to be the main species affecting the process with contributions to the loss of efficacy around 70%. Finally, the material reuse after five adsorption cycles and one regeneration stage with NaOH was assessed under several composition scenarios reaching adsorption yields similar to those obtained with fresh materials. [ABSTRACT FROM AUTHOR]

Abstract: This work investigates the formation of oxidation by-products during the electrochemical removal of ammonium using BDD electrodes from wastewaters containing chlorides. The influence of the initial chloride concentration has been experimentally analyzed first, working with model solutions with variable ammonium concentration and second, with municipal landfill leachates. Two different levels of chloride concentration were studied, i) low chloride concentrations ranging between 0 and 2000 mg/L and, ii) high chloride concentrations ranging between 5000 and 20,000 mg/L. Ammonium removal took place mainly via indirect oxidation leading to the formation of nitrogen gas and nitrate as the main oxidation products; at high chloride concentration the formation of nitrogen gas and the rate of ammonium removal were both favored. However, chloride was also oxidized during the electrochemical treatment leading to the formation of free chlorine responsible of the ammonium oxidation, together with undesirable products such as chloramines, chlorate and perchlorate. Chloramines appeared during the treatment but they reached a maximum and then started decreasing, being totally removed when high chloride concentrations were used. With regard to the formation of chlorate and perchlorate once again the concentration of chloride exerted a strong influence on the formation kinetics of the oxidation by-products and whereas at low chloride concentrations, chlorate appeared like an intermediate compound leading to the formation of perchlorate, at high chloride concentrations chlorate formation was delayed significantly and perchlorate was not detected during the experimental time. Thus this work contributes first to the knowledge of the potential hazards of applying the electro-oxidation technology as an environmental technology to deal with ammonium oxidation under the presence of chloride and second it reports efficient conditions that minimize or even avoid the formation of undesirable by-products. [Copyright &y& Elsevier]

We have investigated the optical and magneto-optical responses of nanoscale ferromagnetic disks by means of numerical simulations, using an extension of the discrete-dipole approximation. Specifically, we studied the case of 5 nm thick cobalt disks in the diameter range from 200 to 1000 nm, illuminated under normal incidence with a wavelength of &LGR; = 632.8 nm. We furthermore assumed the magnetization to lie in the plane of the disk and to be oriented perpendicular to the electric field of the incoming electromagnetic wave, i.e., the transverse magneto-optical Kerr effect configuration. The induced polarization pattern and the near- and far-field optical and magneto-optical responses have been calculated, finding clear nanoscale confinement effects as one reduces the diameter of the disks. However, we also observe that the rather weak magneto-optical response essentially mimics the optical response, and we demonstrate that it can be calculated as a perturbation of the latter with a high degree of accuracy. This strong similarity between the optical and magneto-optical nanoscale confinement effects also results in the fact that the normalized magneto-optically induced far-Held light intensity change, which is the quantity measured in experiments, is only weakly affected even in the case of sub-wavelength-sized disks. [ABSTRACT FROM AUTHOR]

The structure and spatial distribution of the macrofauna community of the Bellingshausen Sea in the western sector of Antarctica was studied during the ‘BENTART–06’ oceanographic expedition. This is one of the least explored Antarctic seas. A total of 20 box cores were sampled at 11 stations ranging from 157 to 3,304 m depth, using an USNEL-type box corer (BC) dredge. Representatives of 25 higher taxa of invertebrates were collected. Deeper sampling sites were less rich in taxa (4–7 taxa), whereas the figures were higher at shallower sites (up to 17 taxa). Faunal density on the sea bottom revealed a horizontal spatial gradient from the western sites with extremely low figures (90 indiv./m2) towards the eastern ones with the highest figures (1,360 indiv./m2) close to the Antarctic Peninsula. Several abiotic factors (depth, redox, organic matter, carbonates and particle size of surficial sediments) were measured simultaneously on the sea floor to characterise the substrate preferences of the fauna. Positive correlations were found between the faunal distribution and a combination of depth, redox values, and organic matter content of sediments. This indicates decreasing availability of food in the deeper bottoms of the Bellingshausen Sea with a prevalence of depauperated bottoms dominated almost exclusively by a foraminiferans community. [ABSTRACT FROM AUTHOR]

Abstract: To develop reliable integrated power electronics, it is paramount to consider the coupling between electrical, thermal and mechanical effects. Though essential for final validation, experimental analysis is time-consuming, especially when trying out new designs. Simulative approaches at multi-domain physical analysis need to be improved. In this work, a platform is proposed, in which all physics are treated with dedicated simulation programmes, co-ordinated by a custom-developed core section. A case study, based on a novel integrated power switch developed for railway traction applications, demonstrates the validity of the envisaged solution for virtual reliability assessment. [Copyright &y& Elsevier]

Radio-frequency thermokeratoplasty (RF-TKP) is a technique used to reshape the cornea curvature by means of thermal lesions using radio-frequency currents. This curvature change allows refractive disorders such as hyperopia to be corrected. A new electrode with ring geometry is proposed for RF-TKP. It was designed to create a single thermal lesion with a full-circle shape. Finite element models were developed, and the temperature distributions in the cornea were analysed for different ring electrode characteristics. The computer results indicated that the maximum temperature in the cornea was located in the vicinity of the ring electrode outer perimeter, and that the lesions had a semi-torus shape. The results also indicated that the electrode thickness, electrode radius and electrode thermal conductivity had a significant influence on the temperature distributions. In addition, in vitro experiments were performed on rabbit eyes. At 5 W power, the lesions were fully circular. Some lesions showed non-uniform characteristics along their circular path. Lesion depth depended on heating duration (60% of corneal thickness for 20 s, and 30% for 10 s). The results suggest that the critical shrinkage temperature (55-63 degrees C) was reached at the central stroma and along the entire circular path in all the cases. [ABSTRACT FROM AUTHOR]

BACKGROUND: Population ageing and changes in the epidemiological profile of neurological pathologies has resulted in an increase in patients with disabilities. Rehabilitation strategies such as Modified Constraint-Induced Movement Therapy (CIMTm) play a key role in treating patients with neurologic deficiencies and motor impairments. This intervention is intended to mitigate disability, promote maximum functional independence, and optimize social and economic participation of patients with upper extremity weakness. Our goal was to assess the recovery of functional independence in patients after a stroke using to CIMTm. PATIENTS AND METHOD: Thirty-six subjects who had suffered stroke took part in a randomised clinical trial. The treatment was applied through either collective or individual modalities for three hours per day for a period of ten days. Participant's functional independence was assessed using the Functional Independence Measure (FIM) scale at the before and after of the intervention. RESULTS: An analysis of covariance carried out on the pre-test assessments indicates that the dependent variable presents significant differences (F1.31 = 42.78, p < 0.001, η2 p = 0.72) in favour of the collective intervention modality. CONCLUSION: Both modalities of CIMTm intervention promote functional independence. However, the greatest improvements were observed in participants in the collective modality. Improvements in functional independence pursue a reduction in learned non-use behaviours through greater use of the paretic upper extremity in everyday activities. [ABSTRACT FROM AUTHOR]

Light emission from long-life phosphorescent pigments is produced in the form of curves whose shape differ from a pure monoexponential decay, due to electron or hole trapping mechanisms taking place in the materials. When the pigments are embedded in dense, scattering media, other light interactions may appear, including scattering, self-absorption or additional non-radiative absorption (heating). For a given pigment concentration, these curves experimentally show a charge saturation effect when the excitation is increased, either by receiving higher intensities or longer exposure times, this process affecting the coefficient of the power-law decay function. The dependence of the emission intensity with the pigment concentration is also shown to produce a saturation effect. The origin of some of these results, obtained from experiments on sintered glass samples with long-life phosphorescent pigments, is explored by means of a multilayer model of photons, where scattering, absorption and emission processes may be governed in each layer and produce an overall reflectance. [ABSTRACT FROM AUTHOR]

Abstract: Based on the on-state voltage drop monitoring at high current, an alternative method for thermo-sensitive parameters calibration is reported. The main goal is that it allows the simultaneous calibration of the series resistance and power devices voltage drop on temperature. Thereby, the average temperature over all power devices and the temperature difference in average inside the pack can be measured in real applications. [Copyright &y& Elsevier]

This study focuses on the changes induced in both the asphericity and homogeneity of the cornea for a group of myopic eyes undergoing LASIK surgery. Eyes were characterized by a Kooijman-based customized eye model in which changes were introduced in the form of Gaussian-distributed refractive-index variations of given correlation length for the inhomogeneities and in the form of an expression, based on the modified Munnerlyn's paraxial formula, for the post-LASIK asphericity. Visual quality was evaluated in terms of the Modulation Transfer Function and the Point-Spread Function. The results show that, on average, the evolution of visual acuity is consistent with the change in corneal asphericity, while the evolution of contrast sensitivity requires a loss in corneal homogeneity in order to be explained. By including both effects in the model, the overall model performance in predicting visual quality is improved. [ABSTRACT FROM AUTHOR]

Introduction: The role of Olanzapine therapeutic drug monitoring is controversial. The present study explores the associations of Olanzapine plasma concentrations with clinical response and metabolic side effects in first episode psychosis (FEP) after 2 months of treatment. Methods: Forty-seven patients were included. Improvement in clinical symptomatology was assessed using the PANSS. Metabolic assessment included weight, blood pressure, waist circumference, blood glucose, total cholesterol, high-density lipoprotein, low-density lipoprotein, and triglycerides. Results: The Olanzapine plasma concentrations after 2 months of treatment were positively correlated with weight gain (r = 0.49, p = 0.003), and a concentration > 23.28 ng/mL was identified as a positive predictor of weight gain (≥ 7%). The Olanzapine concentration to dose (C/D) ratio was positively correlated with the percentage of improvement in the total PANSS (r = 0.46, p = 0.004), and a C/D ratio > 2.12 was identified as a positive predictor of a good response (percentage of improvement > 30%) after 2 months of treatment. We also identified several factors that could alter Olanzapine pharmacokinetics: gender (p = 0.03), diagnosis (p = 0.05), smoking habit (p = 0.05), and co-medications such as valproic acid (p = 0.05) and anxiolytics (p = 0.01). Discussion: In conclusion, our results suggest that therapeutic drug monitoring of Olanzapine could be helpful to evaluate therapeutic efficacy and metabolic dysfunction in FEP patients treated with Olanzapine. [ABSTRACT FROM AUTHOR]

The European Space Agency (ESA) Planetary Science Archive (PSA) is undergoing a significant refactoring of all its components to improve the services provided to the scientific community and the public. The PSA supports ESA's missions exploring the Solar System by archiving scientific peer-reviewed observations as well as engineering data sets. This includes the Giotto, SMART-1, Huygens, Venus Express, Mars Express, Rosetta, Exomars 2016, Exomars RSP, BepiColombo, and JUICE missions. The PSA is offering a newly designed graphical user interface which is simultaneously meant to maximize the interaction with scientific observations and also minimise the efforts needed to download these scientific observations. The PSA still offers the same services as before (i.e., FTP, documentation, helpdesk, etc.). In addition, it will support the two formats of the Planetary Data System (i.e., PDS3 and PDS4), as well as providing new ways for searching the data products with specific metadata and geometrical parameters. As well as enhanced services, the PSA will also provide new services to improve the visualisation of data products and scientific content (e.g., spectra, etc.). Together with improved access to the spacecraft engineering data sets, the PSA will provide easier access to scientific data products that will help to maximize the science return of ESA's space missions. [ABSTRACT FROM AUTHOR]

We report unexpected enhancements of the magneto-optical effect in ferromagnetic Permalloy disks of diameter D < 400 nm. The effect becomes increasingly pronounced for smaller D, reaching more than a 100% enhancement for D = 100 nm samples. By means of experiments and simulations, the origin of this effect is identified as a nanoscale ring-shaped region at the disk edges, in which the magneto-optically induced electric polarization is enhanced. This leads to a modification of the electromagnetic near fields and causes the enhanced magneto-optical excitation, independent from any optical resonance. [ABSTRACT FROM AUTHOR]

The objective is to conduct a longitudinal analysis of the effects of the pandemic and alarm situation on the mental health of the general population at three points in time: two weeks after beginning the confinement, after a month, and after two months, when the lockdown was lifted and the country returned to the new normality. The evaluations were carried out by means of an online survey, with a sample of 3480 persons in the first data collection and 1041 and 569 persons in the successive evaluation periods. The presence of depressive symptoms, anxiety and posttraumatic stress disorder (PTSD) was evaluated by means of screening tests. Sociodemographic data, Covid-19 variables, loneliness, psychological well-being, social support, discrimination and a sense of belonging, were collected. Depressive symptoms increased significantly throughout the confinement, decreasing at the last assessment but not dropping to previous levels. In anxiety, there are no significant changes between the three evaluations, but a downward trend can be seen over time. Regarding the symptomatology of PTSD, a downward trend is observed throughout the three evaluations, with significantly lower scores between the first and third assessments. The different regression models developed reveal the importance of perceived loneliness and spiritual well-being as the main predictors of mental health, as well as the importance of the lower age for depression and the female gender for anxiety and PSTD. This research shows that the pandemic has had a negative impact on our mental health, which still does not seem to be at pre-crisis levels, although it has improved as the emergency situation subsides. These results underline the importance of paying greater attention to mental health, and reveal key variables such as spiritual well-being and perceived loneliness in which to intervene from different care services, as well as younger people and women as vulnerable groups on which to focus more attention. • Covid-19 had a strong impact on the mental health throughout the confinement. • Depression decreased over time, although it did not reach previous levels. • Anxiety remains but a downward trend is observed, and PSTD decreases significantly. • Women and youth have been most affected by the pandemic. • Loneliness and well-being are key variables in predicting mental health impact. [ABSTRACT FROM AUTHOR]

Introduction Stigma towards people with mental illness can have very negative consequences for the persons that experience it. So, it becomes strongly necessary to combat this problem. Objectives/Aims Evaluate the effectiveness of multiple interventions to reduce stigma against mental illness in a group of high school students. Methods Quasi-experimental study. Seventy-six students between 16 to 19 years old from 3 schools of southern Madrid State participated. No significant differences in age and gender between groups were found. The quasi-control group was obtained from 3 different classrooms (1 in each school). This group did not go through any treatment. The experimental group had 2 treatments. Treatment “A” consisted in 1 psychoeducation session. Treatment “B” was 1 visit (real or virtual) to the Thyssen-Bornemisza museum. Persons exercising as museum guides had been diagnosed with mental illness. They already were participants in the PCEA program of the CRPS Latina. The instrument to assess stigma was the AQ-27, validated in Spanish. Results We found significant reductions of stigma in all dimensions explored: Anger (A vs BC; P < 0.001), Threat (A vs BC; P < 0.001), Fear (A vs BC; P < 0.001), Coercion (A vs BC; P < 0.001) Segregation (A vs BC; P < 0.001) and Avoidance (A vs BC; P < 0.001). Conclusions The combination of treatments for intervention on stigma in samples of school students seems to be a very effective option to reduce stigma. [ABSTRACT FROM AUTHOR]