Sector-based Fresnel zone plate with extended depth of focus

A Sector-based Fresnel zone plate consists of a binary diffractive lens composed of a mosaic of sectors of Fresnel zone plates with different focal distances. When these focal distances are linearly distributed within the sectors, dual focus is obtained. Besides, we explore the possibility to generate an extended depth-of-focus lens by using a cubic distribution of the focal distances assigned to the sectors and optimizing the weight factors given to the terms of the cubic polynomial. Finally, numerical simulations based on the Rayleigh-Sommerfeld approach are carried out and experimental verifications by using a Spatial Light Modulator are performed, showing high agreement. The proposed kind of zone plate has potential applications in different research fields such as microscopy, lithography, data storage, or imaging

Numerical model of the inhomogeneous scattering by the human lens

We present in this work a numerical model for characterizing the scattering properties of the human lens. After analyzing the scattering properties of two main scattering particles actually described in the literature through FEM (finite element method) simulations, we have modified a Monte Carlo''s bulk scattering algorithm for computing ray scattering in non-sequential ray tracing. We have implemented this ray scattering algorithm in a layered model of the human lens in order to calculate the scattering properties of the whole lens. We have tested our algorithm by simulating the classic experiment carried out by Van der Berg et al for measuring "in vitro" the angular distribution of forward scattered light by the human lens. The results show the ability of our model to simulate accurately the scattering properties of the human lens. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreemen

Ultra-narrow spectral response of a hybrid plasmonic-grating sensor

We configure and analyze a nanostructured device that hybridizes grating modes and surface plasmon resonances. The model uses an effective index of refraction that considers the volume fraction of the involved materials, and the propagation depth of the plasmon through the structure. Our geometry is an extruded low-order diffraction grating made of dielectric nano-triangles. Surface plasmon resonances are excited at a metal/dielectric interface, which is separated from the analyte by a high-index dielectric layer. The optical performance of the refractometric sensor is highly competitive in sensitivity and figure of merit (FOM) because of the the ultra-narrow spectral response (below 0.1 nm). Moreover, it is operative within a wide range of the index of refraction (from 1.3 till 1.56), and also works under normal incidence conditions.This work was supported in part by the Ministerio de Economía y Competitividad of Spain under Grant TEC2016-77242-C3-1-R and Grant DPI2016-75272-R, in part by the Comunidad de Madrid SINFOTON2-CM under Grant (S2018/NMT-4326), and in part by the European Fund for Regional Development. The work of M. H. Elshorbagy was supported by the Ministry of Higher Education of Egypt (missions section)

Fourier series diffractive lens with extended depth of focus

Angular diffractive lenses have been proven to achieve a narrow beam waist with a long depth of focus. We generalize these type of lenses by defining the angular distribution of the focal length as a Fourier series. The Fourier coefficients of the lens are optimized, using Particle Swarm Optimization algorithm, to minimize the beam width and increase its uniformity for a given depth of focus. In order to obtain a fast simulation during the optimization process, we used Chirp Z-transform algorithm. Finally, we performed an experimental verification of the results using a Spatial Light Modulator. The Fourier series diffractive lens presents a more uniform and narrower beam than previous angular lenses, in both simulations and experiments. These results may find applications in the design of contact and intraocular lenses with extended depth of focus, laser focusing and imaging systems

How to Improve the Functional Capacity of Frail and Pre-Frail Elderly People? Health, Nutritional Status and Exercise Intervention. The EXERNET-Elder 3.0 Project

Aging is associated with the impairment of health and functional capacity, and physical exercise seems to be an effective tool in frailty prevention and treatment. The purpose of this study was to present the methodology used in the EXERNET-Elder 3.0 project that aims to evaluate the immediate and residual effects and of a multicomponent exercise training program called Elder-fit on frailty, fitness, body composition and quality of life, and also to analyse a possible dietary intake interaction according to health and metabolic status. A total of 110 frail and pre-frail elders participated in this study and were divided into a control group (CG = 52) and an intervention group (IG = 58). The IG performed a supervised multicomponent exercise training program of 6 months and 3 days per week, which included strength, endurance, balance, coordination and flexibility exercises, while the CG continued with their usual daily activities. Both groups received four speeches about healthy habits along the project. Four evaluations were performed: at baseline, after 3 months of training, at the end of the training program (6 months) and 4 months after the program had ended to examine the effects of detraining. Evaluating the efficacy, safety and feasibility of this program will help to develop efficacious physical interventions against frailty. Further, protocols should be described accurately to allow exercise programs to be successfully replicated

La actividad física organizada en las personas mayores, una herramienta para mejorar la condición física en la senectud

Fundamentos. Un nivel adecuado de condición física (CF) es fundamental para el logro de un envejecimiento saludable. El objetivo de este estudio consistió en evaluar el impacto de la actividad física (AF) organizada y el número de horas de práctica sobre el nivel de CF de las personas mayores. Método. En el estudio participaron 3104 personas mayores de 65 años de España, pertenecientes al Proyecto Multicéntrico EXERNET (722 hombres y 2382 mujeres; edad media: 72, 1±5, 3 años). La CF se evaluó mediante 8 test específicos para esta población. La participación en AF organizada se registró mediante un cuestionario. Las diferencias en la CF en función de la práctica y número de horas de AF se midieron con ANCOVA ajustando por edad, horas de caminar y de estar sentado. Resultados. Aquellos que no participaban en este tipo de actividad incrementaban su riesgo de tener un nivel bajo de CF en la mayoría de las variables evaluadas, observándose algunas diferencias entre sexos (OR: desde 1, 6 hasta 2, 6 en hombres y desde 1, 4 hasta 2, 2 en mujeres). En los hombres no se observó ninguna diferencia significativa entre practicar menos de 2, 2-4 o más de 4 horas (todos P>0, 05), a excepción de la fuerza del brazo izquierdo; sin embargo, las mujeres que realizaban más de 2 horas de AF organizada a la semana tenían mayor equilibrio, fuerza de piernas y de brazos, flexibilidad de piernas, velocidad al caminar y resistencia aeróbica que aquellas que asistían a este tipo de sesiones menos de 2 horas a la semana (P<0, 05). Conclusiones. La práctica de AF organizada produce un efecto beneficioso sobre la CF de las personas mayores independientemente de la edad, las horas que estén sentados o el tiempo que dediquen a caminar. Background. An adequate level of fitness is critical to achieving healthy ageing. The aim of this study was to evaluate the impact of organized physical activity (PA) and the number of hours of practice on the fitness levels of the elderly. Method. A total of 3104 people over 65 years old from Spain, belonging to the EXERNET Multicenter Project (722 men and 2382 women, mean age: 72.1 +/- 5.3 years) participated in the study. Fitness was evaluated by 8 specific tests for this population. Participation in organized PA was recorded through a questionnaire. Differences in fitness values depending on the participation in PA and the number of hours were measured with ANCOVA adjusting for age, hours of walking and sitting time. Results. Those who did not participate in this type of activity increased their risk of having a low level of fitness in most variables evaluated, with some differences between sexes (OR: from 1.6 to 2.6 in men and from 1.4 to 2.2 in women). In men, no significant differences were observed between practicing less than 2, 2-4 or more than 4 hours (P>0, 05), with an exception in the strength of the left arm. However, women who performed more than 2 hours a week in organized PA had better balance, strength of lower and upper extremities, flexibility of lower extremities, walking speed and aerobic capacity than those who performed less than 2 hours of PA a week (P<0, 05). Conclusions. The practice of organized PA produces a beneficial effect on the fitness of the elderly regardless of age, hours of walking and time sitting per day

Desarrollo de tecnologías para evaluar la funcionalidad de pacientes con prótesis de rodilla y su uso para el seguimiento clínico post-comercialización de productos sanitarios y la estimación de indicadores de gestión hospitalaria

Gomez Pellin, A.; Pedrero, J.; Peris Serra, JL.; Sinovas, I.; Atienza Vicente, CM.; Garrido Jaen, JD.; Bermejo Bosch, I.... (2019). Desarrollo de tecnologías para evaluar la funcionalidad de pacientes con prótesis de rodilla y su uso para el seguimiento clínico post-comercialización de productos sanitarios y la estimación de indicadores de gestión hospitalaria. Innovación biomecánica en Europa. (8):1-4. http://hdl.handle.net/10251/167980S14

How important is current physical fitness for future quality of life? Results from an 8-year longitudinal study on older adults

A vast amount of research has focused on the effects of physical fitness (PF) on mortality, with little research evaluating the effects of PF on future expected health related quality of life (HRQoL). Aim: To evaluate how current PF influences future HRQoL measured in a prospective 8-year study in older adults. Methods: A total of 617 (157 males) older adults (>65y) participated in the study. PF was assessed with the EXERNET battery in 2008–2009 (baseline) and 2016–2017 (follow-up). HRQoL was assessed using the EQ-5D-3L questionnaire in both evaluations. PF tertiles were developed from baseline PF variables: FIT (highest PF values), REGULAR and UNFIT (lowest PF values) taking into account age and sex. Follow-up HRQoL values were compared to sex and age-specific expected values. Logistic regressions were performed to test differences be tween PF tertiles regarding future expected quality of life. Linear regressions were developed to test whether baseline PF could predict future HRQoL scores. Results: The FIT group showed higher probabilities of an improved HRQoL when compared to the UNFIT group. All PF variables seemed to be important at some point of the study except upper extremities flexibility. Aerobic endurance was the variable that showed to be significant for most of the HRQoL predictions. Conclusion: PF influences future HRQoL in older adults who accordingly should try to remain fit to maintain an increased age-adjusted HRQoL

Physical Activity Patterns of the Spanish Population Are Mostly Determined by Sex and Age: Findings in the ANIBES Study

Background Representative data for the Spanish population regarding physical activity (PA) behaviors are scarce and seldom comparable due to methodological inconsistencies. Aim Our objectives were to describe the PA behavior by means of the standardized self-reported International Physical Activity Questionnaire (IPAQ) and to know the proportion of the Spanish population meeting and not meeting international PA recommendations. Material and Methods PA was assessed using the IPAQ in a representative sample of 2285 individuals (males, 50.4%) aged 9–75 years and living in municipalities of at least 2,000 inhabitants. Data were analyzed according to: age groups 9–12, 13–17, 18–64, and 65–75 years; sex; geographical distribution; locality size and educational levels. Results Mean total PA was 868.8±660.9 min/wk, mean vigorous PA 146.4±254.1 min/wk, and mean moderate PA 398.1±408.0 min/wk, showing significant differences between sexes (p<0.05). Children performed higher moderate-vigorous PA than adolescents and seniors (p<0.05), and adults than adolescents and seniors (p<0.05). Compared to recommendations, 36.2%of adults performed <150 min/week of moderate PA, 65.4% <75 min/week of vigorous PA and 27.0%did not perform any PA at all, presenting significant differences between sexes (p<0.05). A total of 55.4%of children and adolescents performed less than 420 min/week of MVPA, being higher in the later (62.6%) than in the former (48.4%). Highest non-compliance was observed in adolescent females (86.5%). Conclusion Sex and age are the main influencing factors on PA in the Spanish population. Males engage in more vigorous and light PA overall, whereas females perform more moderate PA. PA behavior differs between age groups and no clear lineal increase with age could be observed. Twenty-seven percent of adults and 55.4% of children and adolescents do not meet international PA recommendations. Identified target groups should be addressed to increase PA in the Spanish populationCoca-Cola Iberia through Spanish Nutrition Foundation (FEN)Coca-Cola Iberi

Ibero-American Consensus on Low- and No-Calorie Sweeteners: Safety, Nutritional Aspects and Benefits in Food and Beverages

International scientific experts in food, nutrition, dietetics, endocrinology, physical activity, paediatrics, nursing, toxicology and public health met in Lisbon on 2-4 July 2017 to develop a Consensus on the use of low- and no-calorie sweeteners (LNCS) as substitutes for sugars and other caloric sweeteners. LNCS are food additives that are broadly used as sugar substitutes to sweeten foods and beverages with the addition of fewer or no calories. They are also used in medicines, health-care products, such as toothpaste, and food supplements. The goal of this Consensus was to provide a useful, evidence-based, point of reference to assist in efforts to reduce free sugars consumption in line with current international public health recommendations. Participating experts in the Lisbon Consensus analysed and evaluated the evidence in relation to the role of LNCS in food safety, their regulation and the nutritional and dietary aspects of their use in foods and beverages. The conclusions of this Consensus were: (1) LNCS are some of the most extensively evaluated dietary constituents, and their safety has been reviewed and confirmed by regulatory bodies globally including the World Health Organisation, the US Food and Drug Administration and the European Food Safety Authority; (2) Consumer education, which is based on the most robust scientific evidence and regulatory processes, on the use of products containing LNCS should be strengthened in a comprehensive and objective way; (3) The use of LNCS in weight reduction programmes that involve replacing caloric sweeteners with LNCS in the context of structured diet plans may favour sustainable weight reduction. Furthermore, their use in diabetes management programmes may contribute to a better glycaemic control in patients, albeit with modest results. LNCS also provide dental health benefits when used in place of free sugars; (4) It is proposed that foods and beverages with LNCS could be included in dietary guidelines as alternative options to products sweetened with free sugars; (5) Continued education of health professionals is required, since they are a key source of information on issues related to food and health for both the general population and patients. With this in mind, the publication of position statements and consensus documents in the academic literature are extremely desirable