Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
Sensors (Basel) ; 22(5)2022 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-35271191

RESUMEN

This paper presents, for the first time, an absolute linear electromagnetic encoder consisting of a rubber belt with two chains of screen-printed metallic inclusions (rectangular patches). The position, velocity, and direction of the belt (the moving part) is determined by detecting the inclusions when they cross the stator (the static part). The stator is a microstrip line loaded with three complementary split ring resonators (CSRRs), resonant elements exhibiting a resonance frequency perturbed by the presence of inclusions on top of them (contactless). The line is fed by three harmonic signals tuned to the resonance frequencies of the CSRRs. Such signals are generated by a voltage-controlled oscillator (VCO) managed by a microcontroller. The sensed data are retrieved from the pulses contained in the envelope functions of the respective amplitude modulated (AM) signals (caused by the belt motion) generated at the output port of the line. One of the signals provides the absolute belt position, determined by one of the chains, the encoded one. The information relative to the velocity and motion direction is contained in the other AM signals generated by the motion of the other chain, periodic, and thereby, uncoded. The spatial resolution of the system, a figure of merit, is 4 mm. Special emphasis is devoted to the printing process of the belt inclusions.

4.
Sensors (Basel) ; 18(10)2018 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-30261650

RESUMEN

Hydrogel materials offer many advantages for chemical and biological sensoring due to their response to a small change in their environment with a related change in volume. Several designs have been outlined in the literature in the specific field of hydrogel-based optical sensors, reporting a large number of steps for their fabrication. In this work we present a three-dimensional, hydrogel-based sensor the structure of which is fabricated in a single step using thermal nanoimprint lithography. The sensor is based on a waveguide with a grating readout section. A specific hydrogel formulation, based on a combination of PEGDMA (Poly(Ethylene Glycol DiMethAcrylate)), NIPAAm (N-IsoPropylAcrylAmide), and AA (Acrylic Acid), was developed. This stimulus-responsive hydrogel is sensitive to pH and to water. Moreover, the hydrogel has been modified to be suitable for fabrication by thermal nanoimprint lithography. Once stimulated, the hydrogel-based sensor changes its topography, which is characterised physically by AFM and SEM, and optically using a specific optical set-up.

5.
Langmuir ; 30(35): 10728-39, 2014 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-25137566

RESUMEN

Microwave annealing is an emerging technique for achieving ordered patterns of block copolymer films on substrates. Little is understood about the mechanisms of microphase separation during the microwave annealing process and how it promotes the microphase separation of the blocks. Here, we use controlled power microwave irradiation in the presence of tetrahydrofuran (THF) solvent, to achieve lateral microphase separation in high-χ lamellar-forming poly(styrene-b-lactic acid) PS-b-PLA. A highly ordered line pattern was formed within seconds on silicon, germanium and silicon on insulator (SOI) substrates. In-situ temperature measurement of the silicon substrate coupled to condition changes during "solvo-microwave" annealing allowed understanding of the processes to be attained. Our results suggest that the substrate has little effect on the ordering process and is essentially microwave transparent but rather, it is direct heating of the polar THF molecules that causes microphase separation. It is postulated that the rapid interaction of THF with microwaves and the resultant temperature increase to 55 °C within seconds causes an increase of the vapor pressure of the solvent from 19.8 to 70 kPa. This enriched vapor environment increases the plasticity of both PS and PLA chains and leads to the fast self-assembly kinetics. Comparing the patterns formed on silicon, germanium and silicon on insulator (SOI) and also an in situ temperature measurement of silicon in the oven confirms the significance of the solvent over the role of substrate heating during "solvo-microwave" annealing. Besides the short annealing time which has technological importance, the coherence length is on a micron scale and dewetting is not observed after annealing. The etched pattern (PLA was removed by an Ar/O2 reactive ion etch) was transferred to the underlying silicon substrate fabricating sub-20 nm silicon nanowires over large areas demonstrating that the morphology is consistent both across and through the film.

6.
Nanotechnology ; 25(17): 175703, 2014 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-24722230

RESUMEN

Directed self-assembly of block copolymer polystyrene-b-polyethylene oxide (PS-b-PEO) thin film was achieved by a one-pot methodology of solvent vapor assisted nanoimprint lithography (SAIL). Simultaneous solvent-anneal and imprinting of a PS-b-PEO thin film on silicon without surface pre-treatments yielded a 250 nm line grating decorated with 20 nm diameter nanodots array over a large surface area of up to 4' wafer scale. The grazing-incidence small-angle x-ray scattering diffraction pattern showed the fidelity of the NIL stamp pattern replication and confirmed the periodicity of the BCP of 40 nm. The order of the hexagonally arranged nanodot lattice was quantified by SEM image analysis using the opposite partner method and compared to conventionally solvent-annealed block copolymer films. The imprint-based SAIL methodology thus demonstrated an improvement in ordering of the nanodot lattice of up to 50%, and allows significant time and cost reduction in the processing of these structures.


Asunto(s)
Polietilenglicoles/química , Poliestirenos/química , Nanoestructuras/ultraestructura , Difracción de Rayos X
7.
Nano Lett ; 11(10): 4382-5, 2011 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-21875097

RESUMEN

A multichannel surface molecular switch based on self-assembled monolayers (SAMs) on gold of a novel polychlorotriphenylmethyl radical has been fabricated. These SAMs are electrically commutable between two stable redox states that reveal distinct magnetic, optical, and wetting properties that can be employed as read-out mechanisms. The high stability and reversibility of systems like the one reported here further supports the vision of using molecules in the electronic devices of the future.


Asunto(s)
Propiedades de Superficie , Humectabilidad , Electroquímica , Oro/química , Compuestos de Policloroterfenilo/química
8.
Pharmacoeconomics ; 40(1): 91-108, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34480325

RESUMEN

BACKGROUND: Current first-line disease-modifying therapies (DMT) for multiple sclerosis (MS) patients are injectable or oral treatments. The Optogenerapy consortium is developing a novel bioelectronic cell-based implant for controlled release of beta-interferon (IFNß1a) protein into the body. The current study estimated the potential cost effectiveness of the Optogenerapy implant (hereafter: Optoferon) compared with injectable IFNß1a (Avonex). METHODS: A Markov model simulating the costs and effects of Optoferon compared with injectable 30 mg IFNß1a over a 9-year time horizon from a Dutch societal perspective. Costs were reported in 2019 Euros and discounted at a 4% annual rate; health effects were discounted at a 1.5% annual rate. The cohort consisted of 35-year-old, relapsing-remitting MS patients with mild disability. The device is implanted in a daycare setting, and is replaced every 3 years. In the base-case analysis, we assumed equal input parameters for Optoferon and Avonex regarding disability progression, health effects, adverse event probabilities, and acquisition costs. We assumed reduced annual relapse rates and withdrawal rates for Optoferon compared with Avonex. Sensitivity, scenario, value of information, and headroom analysis were performed. RESULTS: Optoferon was the dominant strategy with cost reductions (- €26,966) and health gains (0.45 quality-adjusted life-years gained). A main driver of cost differences are the acquisition costs of Optoferon being 2.5 times less than the costs of Avonex. The incremental cost-effectiveness ratio was most sensitive to variations in the annual acquisition costs of Avonex, the annual withdrawal rate of Avonex and Optoferon, and the disability progression of Avonex. CONCLUSION: Innovative technology such as the Optoferon implant may be a cost-effective therapy for patients with MS. The novel implantable mode of therapeutic protein administration has the potential to become a new mode of treatment administration for MS patients and in other disease areas. However, trials are needed to establish safety and effectiveness.


Asunto(s)
Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Adulto , Análisis Costo-Beneficio , Humanos , Interferón beta-1a , Interferón beta , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico
9.
J Am Chem Soc ; 133(34): 13256-9, 2011 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-21809828

RESUMEN

A self-assembled monolayer of a tetrathiafulvalene derivative on indium tin oxide is shown to operate as a ternary redox switch in which the magnetic and optical outputs are employed to provide a readout of the state. This surface-confined molecular switch exhibits excellent reversibility and stability and is thus promising for the development of molecular electronics.


Asunto(s)
Electrónica/instrumentación , Compuestos Heterocíclicos/química , Compuestos de Estaño/química , Oxidación-Reducción
10.
Cogn Sci ; 43(8): e12781, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31446658

RESUMEN

In two experiments, we examined the impact of color on cognitive performance by asking participants to categorize stimuli presented in three different colors: red, green, and gray (baseline). Participants were either asked to categorize the meaning of words as related to the concepts of "go" or "stop" (Experiment 1) or to indicate if a neutral verbal stimulus was a word or not (lexical decision task, Experiment 2). Overall, we observed performance facilitation in response to go stimuli presented in green (vs. red or gray) and performance inhibition in response to go stimuli presented in red. The opposite pattern was observed for stop-related stimuli. Importantly, results also indicated that color might also be used to categorize neutral stimuli. Overall, these findings provide support to the green-go and red-stop color associations and test the potential functional autonomy acquired by these colors and the boundary conditions to their effects on stimuli categorization.


Asunto(s)
Cognición , Color , Toma de Decisiones , Semántica , Adolescente , Clasificación , Femenino , Humanos , Lenguaje , Masculino , Adulto Joven
11.
Emotion ; 19(3): 503-519, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29999381

RESUMEN

This research investigates the forecasts that people make about the duration of positive versus negative emotions, and tests whether these forecasts differ for self versus for others. Consistent with a motivated thinking framework, six studies show that people make optimistic, asymmetric forecasts that positive emotions will last longer than negative ones. However, for other people, wishful thinking is absent, and therefore people make less optimistic, more symmetric forecasts. Potential implications of these motivated forecasts and self-other differences are discussed. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Asunto(s)
Emociones/fisiología , Humanos , Motivación
12.
ACS Omega ; 4(16): 16781-16788, 2019 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-31646223

RESUMEN

Large-area paper batteries have been explored in this paper, correlating electrode materials and screen printing with the electrochemical performances. The use of office paper embedded in salt solution with two electrodes performed by an easy and large-scale application technique opens doors to a new concept of energy storage. The proposed device is Li-free and uses zinc and silver powder-based screen printable pastes to deposit the electrodes. Cyclic voltammetry and charge-discharge curves reveal the performance of the produced devices using NaCl and KOH solutions in different concentrations. The simulation of electrochemical impedance spectroscopy measurements gave clue of a similar working mechanism to conventional Li-ion batteries. After charging, a single paper battery achieves 1.83 V with 60 mA/cm2 and 90.6% charge-discharge efficiency. As a proof of concept, a small paper battery and a set integrated in series and parallel were used to power a commercial red light-emitting diode.

13.
Sci Data ; 6(1): 32, 2019 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-30996323

RESUMEN

In the Human Penguin Project (N = 1755), 15 research groups from 12 countries collected body temperature, demographic variables, social network indices, seven widely-used psychological scales and two newly developed questionnaires (the Social Thermoregulation and Risk Avoidance Questionnaire (STRAQ-1) and the Kama Muta Frequency Scale (KAMF)). They were collected to investigate the relationship between environmental factors (e.g., geographical, climate etc.) and human behaviors, which is a long-standing inquiry in the scientific community. More specifically, the present project was designed to test principles surrounding the idea of social thermoregulation, which posits that social networks help people to regulate their core body temperature. The results showed that all scales in the current project have sufficient to good psychometrical properties. Unlike previous crowdsourced projects, this dataset includes not only the cleaned raw data but also all the validation of questionnaires in 9 different languages, thus providing a valuable resource for psychological scientists who are interested in cross-national, environment-human interaction studies.


Asunto(s)
Regulación de la Temperatura Corporal , Medio Social , Temperatura Corporal , Regulación de la Temperatura Corporal/fisiología , Clima , Demografía , Humanos , Encuestas y Cuestionarios
14.
J Nonverbal Behav ; 42(3): 311-326, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30174367

RESUMEN

This research investigated the influence of observed touch on the perceptions of communality and dominance in dyadic interactions. We manipulated four key situational features of haptic behavior in two experiments: the initiation, reciprocity, the degree of formality of touch (Studies 1 and 2), and the context of the interaction (Study 2). The results showed that the default perception of touch, irrespective of whether it is initiated or reciprocated, is the communal intention of the toucher. Furthermore, the initiation of touch was seen as an act of dominance, particularly, when the contact between the actors was primed as being hierarchical. Reciprocation neutralized the perceived asymmetry in dominance, but such inferences seemed to hinge on the fit of the touch with the context: reciprocation of formal touch reduced the asymmetry in the hierarchical context, whereas reciprocation of informal touch reduced the asymmetry in the non-hierarchical context.

15.
Front Psychol ; 8: 2023, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29230185

RESUMEN

The Leave campaign in the U.K., which advocated exiting the European Union, emphasized anxiety over immigration and the need to take control of the U.K.'s borders. Citizens who expressed concerns about immigration to the U.K. were more likely to vote to leave. Two correlational studies examined the previously unexplored question of whether the Brexit vote and support for the outcome of the E.U. referendum were linked to individual predictors of prejudice toward foreigners: British collective narcissism (a belief in national greatness), right wing authoritarianism, and social dominance orientation. The results converged to indicate that all three variables were independently related to the perceived threat of immigrants and, via this variable, to the Brexit vote and a support for the outcome of the E.U. referendum. These variables explained the variance in the perceived threat of immigrants and support for the Brexit vote over and above other previously examined predictors such as age, education, or ethnicity, as well as, national identification and national attachment.

16.
ACS Omega ; 2(8): 4417-4423, 2017 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-31457733

RESUMEN

Achieving ultrasmall dimensions of materials and retaining high throughput are critical fabrication considerations for nanotechnology use. This article demonstrates an integrated approach for developing isolated sub-20 nm silicon oxide features through combined "top-down" and "bottom-up" methods: nanoimprint lithography (NIL) and block copolymer (BCP) lithography. Although techniques like those demonstrated here have been developed for nanolithographic application in the microelectronics processing industry, similar approaches could be utilized for sensor, fluidic, and optical-based devices. Thus, this article centers on looking at the possibility of generating isolated silica structures on substrates. NIL was used to create intriguing three-dimensional (3-D) polyhedral oligomeric silsesquioxane (POSS) topographical arrays that guided and confined polystyrene-block-poly(dimethylsiloxane) (PS-b-PDMS) BCP nanofeatures in isolated regions. A cylinder forming PS-b-PDMS BCP system was successfully etched using a one-step etching process to create line-space arrays with a period of 35 nm in confined POSS arrays. We highlight large-area (>6 µm) coverage of line-space arrays in 3-D topographies that could potentially be utilized, for example, in nanofluidic systems. Aligned features for directed self-assembly application are also demonstrated. The high-density, confined silicon oxide nanofeatures in soft lithographic templates over macroscopic areas illustrate the advantages of integrating distinct lithographic methods for attaining discrete features in the deep nanoscale regime.

17.
Front Psychol ; 6: 815, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26124737

RESUMEN

Communion among people is easily identifiable. Close friends or relatives frequently touch each other and this physical contact helps identifying the type of relationship they have. We tested whether a friendly touch and benefits elicit the emotion of gratitude given the close link between gratitude and communal relations. In Study 1, we induced a communal mindset and manipulated friendly touch (vs. non-touch) and benefit to female participants by a female confederate. We measured pre- and post-benefit gratitude, communal feelings, and liking toward the toucher, as well as general affect. In Study 2, we manipulated mindset, friendly touch and benefit, and measured the same variables in female pairs (confederate and participants). In both studies the results showed a main effect of touch on pre-benefit gratitude: participants who were touched by the confederate indicated more gratitude than those not touched. Moreover, benefit increased gratitude toward a confederate in the absence of touch, but not in the presence of touch. Additionally, perceiving the relationship as communal, and not merely liking the confederate, or a positive mood mediated the link between touch and gratitude. The results further support a causal model where touch increases communal feelings, which in turn increase gratitude at the end of the interaction, after having received a benefit from the interaction partner. These results support a broader definition of gratitude as an emotion embodied in communal relationship cues.

18.
Carbohydr Polym ; 126: 40-6, 2015 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-25933520

RESUMEN

Nanofibrillated cellulose, a polymer that can be obtained from one of the most abundant biopolymers in nature, is being increasingly explored due to its outstanding properties for packaging and device applications. Still, open challenges in engineering its intrinsic properties remain to address. To elucidate the optical and mechanical stability of nanofibrillated cellulose as a standalone platform, herein we report on three main findings: (i) for the first time an experimental determination of the optical bandgap of nanofibrillated cellulose, important for future modeling purposes, based on the onset of the optical bandgap of the nanofibrillated cellulose film at Eg≈275 nm (4.5 eV), obtained using absorption and cathodoluminescence measurements. In addition, comparing this result with ab-initio calculations of the electronic structure the exciton binding energy is estimated to be Eex≈800 meV; (ii) hydrostatic pressure experiments revealed that nanofibrillated cellulose is structurally stable at least up to 1.2 GPa; and (iii) surface elastic properties with repeatability better than 5% were observed under moisture cycles with changes of the Young modulus as large as 65%. The results obtained show the precise determination of significant properties as elastic properties and interactions that are compared with similar works and, moreover, demonstrate that nanofibrillated cellulose properties can be reversibly controlled, supporting the extended potential of nanofibrillated cellulose as a robust platform for green-technology applications.


Asunto(s)
Betula/química , Celulosa/química , Celulosa/ultraestructura , Nanofibras/química , Nanofibras/ultraestructura , Módulo de Elasticidad , Tecnología Química Verde/métodos , Luminiscencia , Ensayo de Materiales , Presión , Propiedades de Superficie
19.
PLoS One ; 9(1): e86158, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24465933

RESUMEN

We studied the relation between benefits, perception of social relationships and gratitude. Across three studies, we provide evidence that benefits increase gratitude to the extent to which one applies a mental model of a communal relationship. In Study 1, the communal sharing relational model, and no other relational models, predicted the amount of gratitude participants felt after imagining receiving a benefit from a new acquaintance. In Study 2, participants recalled a large benefit they had received. Applying a communal sharing relational model increased feelings of gratitude for the benefit. In Study 3, we manipulated whether the participant or another person received a benefit from an unknown other. Again, we found that the extent of communal sharing perceived in the relationship with the stranger predicted gratitude. An additional finding of Study 2 was that communal sharing predicted future gratitude regarding the relational partner in a longitudinal design. To conclude, applying a communal sharing model predicts gratitude regarding concrete benefits and regarding the relational partner, presumably because one perceives the communal partner as motivated to meet one's needs. Finally, in Study 3, we found in addition that being the recipient of a benefit without opportunity to repay directly increased communal sharing, and indirectly increased gratitude. These circumstances thus seem to favor the attribution of communal norms, leading to a communal sharing representation and in turn to gratitude. We discuss the importance of relational models as mental representations of relationships for feelings of gratitude.


Asunto(s)
Relaciones Interpersonales , Modelos Teóricos , Percepción Social , Adulto , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Adulto Joven
20.
Neural Regen Res ; 7(2): 101-8, 2012 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25767483

RESUMEN

Changes in social and emotional behaviour have been consistently observed in patients with traumatic brain injury. These changes are associated with emotion recognition deficits which represent one of the major barriers to a successful familiar and social reintegration. In the present study, 32 patients with traumatic brain injury, involving the frontal lobe, and 41 age- and education-matched healthy controls were analyzed. A Go/No-Go task was designed, where each participant had to recognize faces representing three social emotions (arrogance, guilt and jealousy). Results suggested that ability to recognize two social emotions (arrogance and jealousy) was significantly reduced in patients with traumatic brain injury, indicating frontal lesion can reduce emotion recognition ability. In addition, the analysis of the results for hemispheric lesion location (right, left or bilateral) suggested the bilateral lesion sub-group showed a lower accuracy on all social emotions.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA