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This note proposes a novel element removal method for ground structured based topology optimization that utilizes a double-filtering scheme based on a graph representation of the topology. Two types of systems: planar resonators and compliant mechanisms, are used to illustrate the method.

The objective of this study is to develop a novel methodology to assess the energy flow between a nonlinear energy sink (NES) and the primary system it is attached to in terms of energy orientation, which is directly related to the sign of the power present on the primary system. To extend the work done in previous studies, which have focused primarily on the analytical treatment, characterization, and performance evaluation of NES as passive nonlinear dampers for structures under different types of excitations, this study incorporates a methodology for determining whether energy is entering or leaving a primary oscillator when interacting with an NES, by means of considering the power flow of the primary oscillator. Several current measures for evaluating the effectiveness of the NES at extracting and dissipating energy irreversibly are considered through numerical simulations of systems with different damping cases of the NES. Each case provides a different dissipation scenario in the combined system, which is subjected to different types of base excitation signals such as impulse and seismic records. The methodology is further validated experimentally using a two degrees-of-freedom system with an NES attached to the second mass. Comparisons of the modeled responses versus the measured responses are provided for several physical damping realization scenarios in the NES.

With the introduction of renewable energy sources into the power system, transmission system operators need extremely reliable and flexible simulation tools that should also be fast. Sinusoidal predictor method, aims to meet this need by simulating the full-waveform of AC power systems by integrating the arising systems of DAE by trying to free the time step limitation introduced by the frequency of some electrical components. The searched solution is split in a predicted sinusoidal part and a corrector DAE solution part. This paper presents the mathematical convergence of this approach leading to the choice of computing Fourier coefficients by minimizing a function that captures the distance of the desired sinusoidal part of the solution with respect to its oscillating steady state. Using the Dynaωo framework that aims to completely separate the modeling and the solving aspects of power systems, It details latest developments of an add-on in the IDA solver of SUNDIALS and the implementation optimisations. Results on performance speed up of the method computational time using much larger time steps than those used by classical DAE integration methods.

Triboelectric energy harvesters or nanogenerators exploit both contact electrification and electrostatic induction to scavenge excess energy from random motions of mechanical structures. This study focuses on the modeling of triboelectric energy harvesters in the configuration of contact-separation impact oscillators. While mechanical and electrostatic elements in such systems can be satisfactorily modeled based on existing theories, the underlying physics of contact electrification is still under debate. The aim of this work is to introduce the surface charge density of dielectric layers as a variable into the macroscopic equations of motion of triboelectric impact oscillators by experimentally investigating the relation between the impact force and the charge transfer during contact electrification. Specifically, specimens with selected pairs of materials are put under a solenoid-driven pressing tester which charges the specimens with a vertical force whose magnitude, frequency and duty cycle can be controlled. An electrometer is used to monitor the short circuit charge ow between the electrodes from which the charge accumulation on dielectric layers can be extracted. With results from parameter-sweep tests, the produced map from contact force to surface charge density can be integrated into equations of motion via curve fitting or interpolation.

The objective of the manuscript is to explore the effects of geometry on the dynamics of an internally resonant vibrational energy harvester (VEH). Recently, the authors of this manuscript unveiled the existence of ∞6N solutions to design multi-members resonators which exhibit N commensurate frequencies equal to the number of members of the structure. The generalized topology of this family of resonators which exhibit 1:2 resonance resembles a V -shaped structure, i.e., a structure with two members adjoined at an angle φ, denoted as the folding angle. The classic 1:2 internally resonant L-shaped structure is a subset of solutions in this family. This work investigates the effect of the folding angle on the dynamic response of these oscillators. The nonlinear equations of motion are derived by means of Lagrange’s equation, the beams are inextensible yielding second order nonlinearities. Approximate solutions of the model are obtained using the method of multiple scales. The effect of the folding angle on the nonlinear modal interaction in the power- frequency response curves is investigated.

Ultrasonic vibration has been observed to lower the flow stress necessary to initiate plastic deformation, a phenomenon known as "acoustic softening". This unique effect of ultrasound has been extensively applied in welding, machining, forming of metals, and ultrasonic additive manufacturing to lower the yield stress necessary to initiate plastic deformation, it nevertheless lacks fundamental investigation. Some prior studies showed experimental errors due to the design of experimental setups and the associated testing methods that have been introduced, leading to questions about their observations and conclusions. Therefore, an experimental setup described in this paper is designed to minimize the constraints identified from the setups in prior studies. Three types of aluminum are studied: Al 1100-O a commercially pure aluminum, Al 6061-O an aluminum alloy without precipitate strengthening, and Al 6061-T6 a precipitate-strengthened aluminum alloy. The acoustic softening and residual effect are compared based on the similarities and differences in microstructures of the three types of aluminum. In both acoustic softening and residual effect, linear relations are obtained between stress change and ultrasound intensities. The slope defined by the linear relations, i.e. the acoustic softening factor, depends on the microstructure of the specific material. The underlying mechanism of acoustic softening is associated with the activation of dislocations by ultrasonic energy and subsequently their interactions with other dislocations and precipitates, whereas the residual effects are attributed to the permanent changes in dislocation density due to dislocation annihilation, dynamic annealing, and dislocation-precipitate interaction.

BACKGROUND: Studies are required before incorporating egg oral immunotherapy (OIT) into clinical practice. The Spanish Society of Pediatric Allergy, Asthma and Clinical Immunology (SEICAP) conducted a multicenter, randomized controlled study assessing the effectiveness and safety of the OIT using pasteurized egg white (PEW) in egg-allergic children. METHODS: One hundred and one egg-allergic children (6-9years) were randomized for 1year: 25 to an egg-free-diet (CG) and 76 to OIT (target dose 3.3g PEW proteins), PI (30% weekly plus 5% daily increments) or PII (only 30% weekly increments) buildup patterns. Egg skin prick test, sIgE and sIgG4 serum levels, PEW double-blind placebo-controlled food challenge (DBPCFC), and dosing adverse reactions (DARs) were evaluated in all patients from inclusion (T0) until completing 1year of follow-up (T12). At T12, egg-allergic control patients could start OIT. The effectiveness and safety of OIT and the effect of the buildup pattern were analyzed. RESULTS: At T12, 4/25 (16.0%) CG patients passed the PEW DBPCFC vs 64/76 (84.2%) OIT that reached total desensitization (P=0.000); 12 egg-allergic control patients started OIT. Finally, 72/88 (81.81%) patients reached total desensitization, 96.15% PI vs 75.80% on PII (P=0.01). Induction period (121.12±91.43, median 98.00days) was longer in patients on PII buildup pattern, and those with allergic asthma, minor threshold dose, or higher egg sIgE (P

This extended abstract presents a coupling method for the Fluid-Structure Interaction (FSI) problem, which aim is to be conservative and to use classical spaciotemporal discretization methods on each sub-domains; fluid and structure. In this way, the coupling is based on a monolithic formulation and solved by a co-simulation algorithm. The structural sub-domain is spatially discretized by finite elements method and temporally discretized by Newmark implicit scheme. While the fluid sub-domain is discretized by finite volumes method and Runge-Kutta order 2 explicit scheme. The long-term objective is to couple two existing commercial softwares. The proposed method is validated using the one-dimension piston test case.

Los anticuerpos monoclonales (mAb) representan uno de los grupos terapéuticos de mayor interés en el desarrollo farmacológico. Por toda su complejidad (estructural y funcional), el seguimiento farmacocinético de los fármacos biológicos debería ser imprescindible en la práctica clínica habitual. La absorción de los mAb tras su administración intramuscular o subcutánea se puede producir por vía sanguínea o linfática, y su distribución depende del mecanismo de extravasación, la afinidad del mAb para componentes tisulares y del aclaramiento (Cl) tisular. La eliminación se produce principalmente por proteolisis intracelular tras una endocitosis específica (mediada por receptor) o inespecífica. Por otro lado, la captación y posterior liberación del mAb, la redistribución del flujo sanguíneo por procesos fisiológicos, la formación de complejos y el proceso de reciclaje mediante el receptor de Brambell son los mecanismos fisiológicos que condicionan su variabilidad farmacocinética intraindividual. Además, la inmunogenicidad frente al mAb, el peso del paciente y la cantidad de antígeno diana son los principales factores que afectan a su variabilidad farmacocinética. Palabras clave: Anticuerpo monoclonal, farmacocinética, variabilidad.

Los fármacos biológicos se han convertido en agentes clave para el tratamiento de las enfermedades inflamatorias inmunomediadas (IMID). Sin embargo, la terapia biológica está condicionada por la gran variabilidad farmacocinética (PK) inter/ intraindividual. La monitorización terapéutica (TDM), basada en las concentraciones de fármaco biológico y los anticuerpos antifármaco, es una herramienta apropiada para la optimización del tratamiento de las IMID con el objetivo de individualizar la posología para cada paciente. Así, la determinación de concentraciones plasmáticas de los agentes biológicos, junto con la interpretación de los valores clínicos y analíticos, permitiría una evaluación global del estado del paciente, optimizar la exposición al fármaco y mejorar la respuesta clínica. La monitorización de concentraciones plasmáticas se puede realizar en caso de no respuesta (TDM reactiva) o en caso de remisión para mantener una exposición al fármaco adecuada (TDM proactiva). En este artículo se resume la información disponible sobre la TDM de los agentes biológicos para la optimización del tratamiento de la artritis reumatoide (AR). A pesar de la evidencia disponible sobre la asociación entre las concentraciones séricas de fármacos y el resultado clínico en AR, se requieren más datos PK y de coste-efectividad que permitan obtener más información para consolidar la TDM como una intervención en reumatología. Palabras clave: Artritis reumatoide, agente biológico, monitorización farmacocinética.

En el presente trabajo se da a conocer la presencia de troncos con perforaciones en la Formación Arcillas de Morella (Aptiense Inferior, Castellón). Se han reconocido dos formas correspondientes a dos icnoespecies diferentes: Teredolites clavatus y Teredolites longissimus. Las perforaciones se asignan a la actividad perforante de bivalvos de las familias Pholadidae y Teredinidae. La presencia de estas perforaciones en los niveles superiores de la Formación Arcillas de Morella, junto con el contenido paleontológico asociado a éstas, así como las estructuras sedimentarias de los diferentes materiales, confirman que estos depósitos poseen una clara influencia mareal. La base del nivel con Teredolites corresponde a una superfi cie transgresiva (TS) que separaría los depósitos continentales del cortejo de bajo nivel del mar (LST) caracterizado por las facies de arcillas rojas de la mitad inferior de la unidad, de los del cortejo transgresivo (TST), constituido por las facies heterolítico-arenosas de la parte superior de esta formación, de clara influencia mareal.

Background The sensitisation profile at molecular level in plant-food allergy is complex. Several allergens may be involved, with different potential for severe reactions. lipid transfer proteins (LTP) are considered the most relevant plant-food allergens in adults in Mediterranean countries, but less is known in children. Aim To describe the clinical pattern and sensitisation profile of children with plant-food allergy and LTP sensitisation from Northeast Spain. Methods Children with history of immediate reaction to plant-food(s), positive skin-prick-test to the culprit plant-food(s) and specific-IgE to plant-food LTPs were analysed. Results 130 children were included. 69.2% (90/130) had reacted to ≥2 taxonomically unrelated plant-foods. Peach, walnut, hazelnut and peanut were most frequently involved. Reactions severity ranged from anaphylaxis (45.4%, 59/130) to oral symptoms only. Sensitisation to a particular plant-food LTP not always caused clinical symptoms with that plant-food; 69% (40/58) and 63% (17/27) of peach- and walnut-tolerant subjects had positive rPru p 3 and nJug r 3 specific IgE, respectively. 65.4% (85/130) of children were also sensitised to storage proteins, which was associated to anaphylaxis and nut allergy. However, 60% of patients without nuts/seeds allergy were sensitised to storage proteins. Specific-IgE levels to LTPs and/or storage proteins were not useful to predict allergy (vs. tolerance) to peach, walnut, peanut or hazelnut. Conclusions Sensitisation to LTP and/or storage proteins without clear clinical significance is relatively common. Prospective longitudinal studies are required to evaluate the relevance of these silent sensitisations over time. Caution is required when interpreting the results of molecular-based diagnostic tools in clinical practice.

Polyethylene (PE) foam is a material used commonly in protective packaging for its shock absorption properties. When developing a package design intended to mitigate shock to the product, decisions are typically made based on established cushion evaluation procedures performed at standard laboratory conditions. Distribution environment temperatures, however, can vary greatly from the condition at which these materials are assessed. The research presented in this paper utilizes the stress–energy method of cushion evaluation and highlights trends in the stress–energy equations of PE foam tested at 12 different temperatures, ranging from −20°C to 50°C. A quadratic polynomial is used to describe the variation in the stress–energy equation coefficients over the temperature range evaluated. The model developed enables cushion curve prediction for any static stress, drop height, material thickness and temperature expected over the intended range of use of the material. This model is validated by performing additional impact testing of samples at various temperatures and comparing experimentally obtained acceleration values to those predicted by the model. Further model analysis is performed to estimate the optimal static stress for the material at any temperature within the range tested and to study the variation with temperature of this optimal point. Results reveal that the model developed is capable of predicting the shock absorption properties of the material within the range of parameters tested and that the optimal static stress of the material decreases as temperature increases from −20°C to 50°C. Application to cushion design is made to recommend an approach to designing a PE cushion system for use over a range of temperatures. Copyright © 2016 John Wiley & Sons, Ltd.

Knowledge of the evaporative loss from lakes and reservoirs is critical to water resources managers as well as to the overall understanding of the water balance in a given basin, geographical region, or continent. Existing methods for ascertaining evaporation from lakes and reservoirs include point measurements, water balance and mass transfer calculations, and proxy measurements using a pan. Point measurements using the eddy flux covariance method can be accurate, but are resource intensive and unsuited for determining spatial variation over a lake, or for obtaining measurements over many lakes. Mass balance methods cannot provide spatial variability and their accuracy depends on other portions of the water balance that can be challenging to obtain, such as leakage. Similarly, relatively recently deployed scintillation methods provide only an average for a strip across a lake and are also resource intensive and not suited for multi-lake studies. Evaporation pan measurements can also be used, though their accuracy is poor. Herein, we use a combination of Moderate Resolution Imaging Spectroradiometer (MODIS) satellite measurements of water surface temperature, measurements of wind speed, air temperature, and relative humidity from local NWS stations, and a mass transfer method, to demonstrate multi-lake evaporation measurements. Specifically, the seasonal variation in evaporation is obtained for the five major lakes in the Savannah River Basin (in South Carolina, USA): Lakes Jocassee, Keowee, Hartwell, Russell, and Thurmond. Since this approach requires only an existing satellite resource with global coverage and existing NWS stations, this method can potentially be ported to any lake where there is a nearby meteorology station. Hence, this method could be used by both water resource managers and limnologists alike. The possibility is discussed of extending this approach beyond a single basin to encompass an entire geographical region or continent.

Background The number of consultations for sexually transmitted infections (STIs) is increasing in Spain. The aim of this study was to describe and analyze the epidemiological, behavioral, clinical, and microbiological characteristics of patients registered at the STI unit of a tertiary hospital. Methods This was a retrospective, single-center descriptive study carried out between 2010 and 2013 in a multidisciplinary unit specialized in STIs, situated in a tertiary hospital. Epidemiological, clinical, and behavioral data were gathered using a face-to-face interview and a standardized questionnaire. Samples were collected for microbiology analysis. Results The study included 546 patients: 96% were men, 41% had human immunodeficiency virus (HIV) infection, and 56% were men who have sex with men. The reasons for consultation were the following: urethritis; genital, anal, or perianal ulcers; proctitis; oral ulcers; sexual contact with a person with a known STI; and high-risk sexual contact. The most common microbiological diagnoses were Neisseria gonorrhoeae in urethritis, Treponema pallidum in genital and anal or perianal ulcers, and Chlamydia trachomatis lymphogranuloma venereum serovars in proctitis. The highest prevalences of the main STIs studied occurred in homosexual men with HIV infection. Conclusion This study confirms the increase in the incidence of STIs in recent years and the epidemiological characteristics of the HIV/STI epidemic in Spain.

Resumen Introduccion Las infecciones de transmision sexual son un motivo de consulta creciente en nuestro medio. El objetivo de este trabajo es describir y analizar las caracteristicas epidemiologicas, conductuales, clinicas y microbiologicas de los pacientes registrados en una unidad de infecciones de transmision sexual de un hospital terciario. Metodos Estudio descriptivo, retrospectivo y unicentrico realizado en una unidad multidisciplinar especializada en infecciones de transmision sexual de un hospital terciario entre 2010 y 2013. Se recogieron datos epidemiologicos, clinicos y conductuales mediante entrevista oral abierta y cuestionario estandarizado, y se llevo a cabo la obtencion de muestras para estudio microbiologico. Resultados Se estudiaron 546 pacientes, de los cuales fueron 96% varones, 41% infectados por el VIH, 56% hombres que tienen sexo con hombres. Los motivos de consulta mas prevalentes fueron: uretritis, ulceras genitales y/o anales/perianales, proctitis, ulceras orales, contacto sexual de persona con ITS conocida y contacto sexual de riesgo. Los diagnosticos microbiologicos mas frecuentes fueron: Neisseria gonorrhoeae en uretritis, Treponema pallidum en ulceras genitales y/o anales/perianales y Chlamydia trachomatis serovares de linfogranuloma venereo en proctitis. Las principales ITS estudiadas fueron mas prevalentes en varones homosexuales e infectados por el VIH. Conclusion Se confirma el incremento en la incidencia de las infecciones de transmision sexual en los ultimos anos y las caracteristicas epidemiologicas de la epidemia VIH/ITS de nuestro entorno.