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Mohammad Reza Djodeyre,1 Jaime Beltran,2 Julio Ortega-Usobiaga,3 Felix Gonzalez-Lopez,4 Ana Isabel Ruiz-Rizaldos,1 Julio Baviera2 1Department of Refractive Surgery, Clinica Baviera, Zaragoza, 2Department of Refractive Surgery, Clinica Baviera, Valencia, 3Department of Research and Development, Clinica Baviera, Bilbao, 4Department of Refractive Surgery, Clinica Baviera, Madrid, Spain Purpose: To study long-term refractive and visual outcomes of laser in situ keratomileusis (LASIK) in eyes with a postoperative thin central cornea. Methods: In this retrospective observational case series, we studied 282 myopic eyes with a normal preoperative topographic pattern and postoperative thin corneas (275 µm. Keywords: LASIK, thin, cornea, ectasia, myopia, pachymetry, topography

A recent theory (Tirumkudulu & Paramati, Phys. Fluids, vol. 25, 2013, 102107) for a radially expanding liquid sheet, that accounts for liquid inertia, interfacial tension and thinning of the liquid sheet while ignoring the inertia of the surrounding gas and viscous effects, shows that such a sheet is convectively unstable to small sinuous disturbances at all frequencies and Weber numbers $(We\equiv {\it\rho}_{l}U^{2}h/{\it\sigma})$. Here, ${\it\rho}_{l}$ and ${\it\sigma}$ are the density and surface tension of the liquid, respectively, $U$ is the speed of the liquid jet, and $h$ is the local sheet thickness. In this study we use a simple non-contact optical technique based on laser-induced fluorescence (LIF) to measure the instantaneous local sheet thickness and displacement of a circular sheet produced by head-on impingement of two laminar jets. When the impingement point is disturbed via acoustic forcing, sinuous waves produced close to the impingement point travel radially outwards. The phase speed of the sinuous wave decreases while the amplitude grows as they propagate radially outwards. Our experimental technique was unable to detect thickness modulations in the presence of forcing, suggesting that the modulations could be smaller than the resolution of our experimental technique. The measured phase speed of the sinuous wave envelope matches with theoretical predictions while there is a qualitative agreement in the case of spatial growth. We show that there is a range of frequencies over which the sheet is unstable due to both aerodynamic interaction and thinning effects, while outside this range, thinning effects dominate. These results imply that a full theory that describes the dynamics of a radially expanding liquid sheet should account for both effects.

Optical diffusers provide a solution for a variety of applications requiring a Gaussian intensity distribution including imaging systems, biomedical optics, and aerospace. Advances in laser ablation processes have allowed the rapid production of efficient optical diffusers. Here, we demonstrate a novel technique to fabricate high-quality glass optical diffusers with cost-efficiency using a continuous CO2 laser. Surface relief pseudorandom microstructures were patterned on both sides of the glass substrates. A numerical simulation of the temperature distribution showed that the CO2 laser drills a 137 μm hole in the glass for every 2 ms of processing time. FFT simulation was utilized to design predictable optical diffusers. The pseudorandom microstructures were characterized by optical microscopy, Raman spectroscopy, and angle-resolved spectroscopy to assess their chemical properties, optical scattering, transmittance, and polarization response. Increasing laser exposure and the number of diffusing surfaces enhanced the diffusion and homogenized the incident light. The recorded speckle pattern showed high contrast with sharp bright spot free diffusion in the far field view range (250 mm). A model of glass surface peeling was also developed to prevent its occurrence during the fabrication process. The demonstrated method provides an economical approach in fabricating optical glass diffusers in a controlled and predictable manner. The produced optical diffusers have application in fibre optics, LED systems, and spotlights.

International audience; Metal-elastomer interfacial systems, often encountered in stretchable electronics, demonstrate remarkably high interface fracture toughness values. Evidently, a large gap exists between the rather small adhesion energy levels at the microscopic scale (‘intrinsic adhesion’) and the large measured macroscopic work-of-separation. This energy gap is closed here by unravelling the underlying dissipative mechanisms through a systematic numerical/experimental multi-scale approach. This self-containing contribution collects and reviews previously published results and addresses the remaining open questions by providing new and independent results obtained from an alternative experimental set-up. In particular, the experimental studies on Cu-PDMS (Poly(dimethylsiloxane)) samples conclusively reveal the essential role of fibrillation mechanisms at the micro-meter scale during the metal-elastomer delamination process. The micro-scale numerical analyses on single and multiple fibrils show that the dynamic release of the stored elastic energy by multiple fibril fracture, including the interaction with the adjacent deforming bulk PDMS and its highly nonlinear behaviour, provide a mechanistic understanding of the high work-of-separation. An experimentally validated quantitative relation between the macroscopic work-of-separation and peel front height is established from the simulation results. Finally, it is shown that a micro-mechanically motivated shape of the traction-separation law in cohesive zone models is essential to describe the delamination process in fibrillating metal-elastomer systems in a physically meaningful way.

Let A be a finite or countable alphabet and let $\theta$ be a literal (anti-)automorphism onto A * (by definition, such a correspondence is determinated by a permutation of the alphabet). This paper deals with sets which are invariant under $\theta$ ($\theta$-invariant for short) that is, languages L such that $\theta$ (L) is a subset of L.We establish an extension of the famous defect theorem. With regards to the so-called notion of completeness, we provide a series of examples of finite complete $\theta$-invariant codes. Moreover, we establish a formula which allows to embed any non-complete $\theta$-invariant code into a complete one. As a consequence, in the family of the so-called thin $\theta$--invariant codes, maximality and completeness are two equivalent notions., Comment: arXiv admin note: text overlap with arXiv:1705.05564

WOS: 000443021000068, A metamaterial-based permittivity and thickness sensor structure for dielectric substrate material has been proposed at the X band frequency regime. The sensor structure is designed by using a split meander line type resonator and examining it both numerically and experimentally. Various types of dielectric substrate samples have been used to verify the precise sensing characteristics of the proposed sensor. The sensor layer has been chosen as the back side of the sensor structure, and the reflection frequency of the incident signal has been examined The sensor layer thickness has been varied from 0.4 mm to 1.6 mm for the thickness sensing study with two different types of dielectric substrate having the same electromagnetic characteristics. The permittivity sensing study has been carried out by several dielectric materials which have permittivity values between 10.20 and 1.96. The proposed sensor structure can be effectively used in many application areas such as microwave material design, the defense industry and in medical devices., Scientific Project Unit of Cukurova University [FDK-2018-10488], The authors would like to acknowledge the Scientific Project Unit of Cukurova University (FDK-2018-10488).

WOS: 000431278700009, Metamaterial-based energy harvesting structures operating at GSM goo and GSM 1800 frequency bands have been proposed. The basic structure is composed of four nested U-shaped elements on the front and back side of the dielectric substrate, with a 180 degrees relationship between the front and back resonators. As energy harvesting capability is directly related to the quality of absorption, with the aim being perfect absorption, there is an air gap to allow tuning of the resonance frequency, and copper plate follows the air gap to facilitate the perfect absorption of electromagnetic waves, which is verified by means of simulation and experimental tests. A set of simulations and experimental study were further carried out to demonstrate incident and polarization angle dependency, the effects of Schottky diodes, and the optimal orientation of the U-shapes. Spectrum analysis and DC voltage measurements across the HSMS 2860 Schottky diode are also presented to test the energy harvesting capability: the spectrum analyzer shows a 40 dBm difference, while 81.7 mV maximum DC voltage is observed at 900 MHz. The simulation and experimental study results, while displaying several differences, do suggest that the proposed design can be used for running low-energy consumption devices such as sensors and switches.

OBJECTIVES: UK primary care databases (PCDs) are used by researchers worldwide to inform clinical practice. These databases have been primarily tied to single clinical computer systems, but little is known about the adoption of these systems by primary care practices or their geographical representativeness. We explore the spatial distribution of clinical computing systems and discuss the implications for the longevity and regional representativeness of these resources. DESIGN: Cross-sectional study. SETTING: English primary care clinical computer systems. PARTICIPANTS: 7526 general practices in August 2016. METHODS: Spatial mapping of family practices in England in 2016 by clinical computer system at two geographical levels, the lower Clinical Commissioning Group (CCG, 209 units) and the higher National Health Service regions (14 units). Data for practices included numbers of doctors, nurses and patients, and area deprivation. RESULTS: Of 7526 practices, Egton Medical Information Systems (EMIS) was used in 4199 (56%), SystmOne in 2552 (34%) and Vision in 636 (9%). Great regional variability was observed for all systems, with EMIS having a stronger presence in the West of England, London and the South; SystmOne in the East and some regions in the South; and Vision in London, the South, Greater Manchester and Birmingham. CONCLUSIONS: PCDs based on single clinical computer systems are geographically clustered in England. For example, Clinical Practice Research Datalink and The Health Improvement Network, the most popular primary care databases in terms of research outputs, are based on the Vision clinical computer system, used by

International audience; Thin porous media (TPM) are porous layers that are characterized by a small thickness, usually orders of magnitude smaller than the lateral dimensions. We present pore network simulation revealing that drying of TPM is substantially different from drying of thicker porous media because of the impact of the small thickness of only a few pore layers on the liquid phase structure during drying. The small thickness limits the long-distance connectivity within the liquid clusters and thus causes the formation of smaller clusters characterized by shorter residence times. As a result of this stronger and earlier liquid phase fragmentation the drying of TPM is shown to be significantly more sensitive to the distribution of the evaporation flux at the surface. It is also shown that the drying behavior transition from thin to thick porous media is progressive. Moreover, it is discussed how an imposed temperature distribution can be used to control the evolution of the liquid cluster distribution in a TPM and thereby the evolution of the evaporation rate.

Cerio (IV) oksido funkcinių keramikų tyrimai yra perspektyvi tyrimų sritis. Pramonėje plačiai naudojamos СeO2–Gd2O3 ir СeO2–Sm2O3 kompozicinės medžiagos. Šiame darbe plonos CeO2 su 10 mol% Gd2O3 (GDC10), CeO2 su 20 mol% Gd2O3 (GDC20), CeO2 su 15 mol% Sm2O3 (SDC15), CeO2 su 20 mol% Sm2O3 (SDC20) dangos buvo suformuotos naudojant garinimą elektronų spinduliu. Naudojant šį metodą, nusodinimo greitis ir padėklo temperatūra įtakojo suformuotų legiruoto cerio oksido plonų dangų savybes. Legiruotos (Sm ir Gd) plonos cerio oksido plonos dangos (~ 1,9 µm) buvo užneštos ant SiO2, Alloy 600 (Fe-Ni-Cr), Si (111), Si (100) ir Al2O3 padėklų. Suformuotų plonų dangų tyrimai buvo atlikti skenuojančiu elektroniniu mikroskopu (SEM), elektronų dispersinės spektroskopijos (EDS), Rentgeno spindulių difrakcijos (XRD) metodais ir Ramano spektroskopijos metodu. Darbe buvo nustatyta, kad suformuoti ploni GDC bei SDC sluoksniai turi kristalinę struktūrą, nepriklausomai nuo priemaišų kiekio ir naudojamo padėklo. Dominuojanti kristalografinė orientacija buvo kubinė (111). Naudojant Ramano spektroskopiją buvo nustatyta gryno cerio smailė (465cm-1) atitinkanti F2g vibracinį lygmenį. Būdingos pirmos eilės cerio oksido smailės, keičiant priemaišų koncentraciją, pasislenka į mažesnių bangos skaičių sritį. Visų suformuotų GDC bei SDC plonų sluoksnių Ramano smailės buvo panašios viena į kitą savo forma. Tiriamos dangos sudėties sąlygojo smailių padėtį, jų pusplotį bei intensyvumą. Tyrimuose nustatytos 550 cm-1 ir 600 cm-1 smailių padėtys paaiškina deguonies vakansijų skaičiaus kitimą dėl cerio valentingumo pokyčio, t.y. Се3+⇄Се4+., The investigation of new functional materials (ceramics) based on cerium (IV) oxides is a promising field of scientific research. A wide application in the industry received composite materials based on СeO2–Gd2O3 and СeO2–Sm2O3. In this work thin films were formed on the basis of (CeO2 with 10 mol% Gd2O3 (GDC10), CeO2 with 20 mol% Gd2O3 (GDC20), CeO2 with 15 mol% Sm2O3 (SDC15), CeO2 with 20 mol% Sm2O3 (SDC20)) using e-beam technique in this work. The deposition rate and temperature of the substrate had influence on the formed doped cerium oxide (SDC and GDC) thin films properties. Sm and Gd doped cerium oxide thin films (~1.9 µm) were deposited on SiO2, Alloy 600 (Fe-Ni-Cr), Si(111), Si (100) and Al2O3 substrates. Investigations of the formed thin films were carried out using a Scanning electron microscope (SEM), Electron dispersive spectroscopy (EDS), X-ray diffraction (XRD), and Raman spectroscopy. It has been established that the cerium oxide based ceramic retains the crystalline structure, regardless of the concentration of the dopant and used substrate type. The most dominant crystallographic orientation of formed thin films was cubic (111). Raman spectroscopy measurements showed the peak (465cm-1) of pure ceria corresponding to F2g vibrational mode. First-order peaks, inherent to cerium oxide, were shifted to a region of lower wavenumbers and depend on dopant concentration. The peaks for all formed thin films were similar to each other in form but the position, half width and their intensity varied depending on the dopant concentration. Raman peaks position at 550 cm-1 and 600 cm-1 could be explained as change of oxygen vacancy amount due to the cerium transition between oxidized and reduced forms of Се3+⇄Се4+.

Electronic health records hold great promise for clinical and epidemiologic research. Undertaking atopic eczema (AE) research using such data is challenging because of its episodic and heterogeneous nature. We sought to develop and validate a diagnostic algorithm that identifies AE cases based on codes used for electronic records used in the UK Health Improvement Network. We found that at least one of five diagnosis codes plus two treatment codes for any skin-directed therapy were likely to accurately identify patients with AE. To validate this algorithm, a questionnaire was sent to the physicians of 200 randomly selected children and adults. The primary outcome, positive predictive value for a physician-confirmed diagnosis of AE, was 86% (95% confidence interval= 80-91). Additional criteria increased the PPV up to 95% but would miss up to 89% of individuals with physician-confirmed AE. The first and last entered diagnosis codes for individuals showed good agreement with the physician-confirmed age at onset and last disease activity; the mean difference was 0.8 years (95% confidence interval= -0.3 to 1.9) and -1.3 years (95% confidence interval= -2.5 to -0.1), respectively. A combination of diagnostic and prescription codes can be used to reliably estimate the diagnosis and duration of AE from The Health Improvement Network primary care electronic health records in the UK.

This paper describes the concept, form finding, fabrication and experimental testing of a prototype floor system, derived from principles of shallow arching action, to initiate internal compressive stresses rather than exclusively flexural stresses. This vaulting in a floor system leads to a lightweight structural element, with significant weight savings compared to traditional concrete floor slabs. The form finding process to generate the floor geometry is presented, with a description of the fabrication process, the concrete mix design, material testing and experimental testing. The results from the serviceability and ultimate load testing of the prototype floor are documented in detail. The data showed that the floor unit was both stiff under service load, with maximum vertical deflections less than span/2500, as well as possessing sufficient strength for ultimate loading, carrying 2.5 times the factored design load in a more critical asymmetric loading scenario. A camera setup was used to measure displacements in-line with traditional displacement transducers, to give contour plots of vertical deflections.

International audience; A carefully controlled, custom-built adhesion testing device was developed which allows a precise, short dwell time on the order of milliseconds to be applied during a contact adhesion experiment. The dwell time dependence of the adhesive strength of crosslinked poly(dimethylsiloxane) (PDMS) in contact with glass and uncrosslinked styrene butadiene rubber (SBR) in contact with glass and with itself was tested with a spherical probe in a confined Johnson-Kendall-Roberts (JKR) geometry. Analysis of the contact images revealed several unique separation mechanisms which are dependent on dwell time and interfacial properties. PDMS-glass interfaces show essentially no dependence of adhesion on the dwell time while the adhesive strength and separation mechanisms of SBR interfaces are shown to vary drastically for dwell times ranging from 40 to 10?000 ms. This influence of dwell time is particularly pronounced for polymer-polymer (SBR-SBR) interfaces. Observations of cavitation due to trapped air pockets in the center of the contact at very short contact times illustrate a transition between a defect-controlled debonding and an interface-controlled debonding which has not been previously reported.

Reducing absorber layer thickness below 500nm in regular Cu(In,Ga)Se-2 (CIGS) solar cells decreases cell efficiency considerably, as both short-circuit current and open-circuit voltage are reduced because of incomplete absorption and high Mo/CIGS rear interface recombination. In this work, an innovative rear cell design is developed to avoid both effects: a highly reflective rear surface passivation layer with nano-sized local point contact openings is employed to enhance rear internal reflection and decrease the rear surface recombination velocity significantly, as compared with a standard Mo/CIGS rear interface. The formation of nano-sphere shaped precipitates in chemical bath deposition of CdS is used to generate nano-sized point contact openings. Evaporation of MgF2 coated with a thin atomic layer deposited Al2O3 layer, or direct current magnetron sputtering of Al2O3 are used as rear surface passivation layers. Rear internal reflection is enhanced substantially by the increased thickness of the passivation layer, and also the rear surface recombination velocity is reduced at the Al2O3/CIGS rear interface. (MgF2/)Al2O3 rear surface passivated ultra-thin CIGS solar cells are fabricated, showing an increase in short circuit current and open circuit voltage compared to unpassivated reference cells with equivalent CIGS thickness. Accordingly, average solar cell efficiencies of 13.5% are realized for 385nm thick CIGS absorber layers, compared with 9.1% efficiency for the corresponding unpassivated reference cells. (c) 2014 The Authors. Progress in Photovoltaics: Research and Applications published by John Wiley & Sons Ltd. B. Vermang acknowledges the financial support of the European Commission via FP7 Marie Curie IEF 2011 Action No. 300998. Furthermore, this work is partly funded by the Swedish Science Foundation (VR) and the Swedish Energy Agency. Lastly, F. Henry would like to thank the European and Wallonia Region FEDER grant ECP12020011678F (MINATIS Project) for financial support.

Polymer membranes are of increasing importance for a range of molecular separations due to their potential for enhanced energy-efficiency over competing technologies.1 For example, gas separation using polymer membranes is an established industrial technology that is applied to O2 or N2 enrichment of air, natural gas upgrading (i.e., predominantly removing CO2 from CH4), and hydrogen recovery from ammonia manufacture (separating H2 from N2).2 In addition, polymer membranes are also predicted to play an increasing role in hydrogen production (e.g., separating H2 from CO2)3 and post-combustion capture of CO2 (separating CO2 from N2).4 For any gas separation membrane it is desirable to have good selectivity for one gas over another, combined with high permeability (i.e., flux or throughput). Generally, polymers used for commercial gas separation membranes demonstrate high selectivity but low permeability, however, to compete with other technologies for very large-scale applications, membrane materials with greatly enhanced gas permeabilities are desirable.5 Unfortunately, for the separation of a given gas pair (x and y), highly permeable polymers display inadequate selectivity due to the well-established trade-off between permeability (Px) and selectivity (αxy = Px/Py). For example, one of the most permeable polymers, poly(trimethylsilylpropyne), has very poor selectivity (e.g., PO2 = 6000 Barrer; αO2/N2 = 1.8).6 The permeability-selectivity trade-off was quantified by Robeson in 1991,7 and revised in 2008,8 by plotting log Px versus log αxy for a large number of polymers. For each gas pair, an “upper bound” was identified and the position of the gas permeability data relative to the upper bound is used as a universal performance indicator when assessing the potential of a new polymer as a membrane material for the separation of the two gases. The position of the Robeson upper bound for each gas pair is related to the difference in the kinetic diameter of the gas molecules and the size-sieving nature (i.e., diffusivity selectivity) of the rigid glassy polymers that define it.9 Theory suggests that greater selectivity can be obtained by suppressing polymer motion by increasing chain rigidity whereas high gas permeability relies on the generation of a large amount of free volume through large inter-chain separation.[9b] Conforming to these design criteria, Polymers of Intrinsic Microporosity (PIMs), such as the archetypal PIM-1 (Figure ​1a),1a), are a class of membrane-forming polymer that are designed to possess a wholly fused-ring structure to restrict chain motion and a contorted chain structure to prohibit space efficient packing.10 Hence, gas permeability data for PIMs generally lie over the 1991 upper bound for most important gas pairs and some approach, or even exceed, the 2008 upper bounds (Figure ​22).11

This paper describes the development of an inexpensive, highly portable photogrammetry technique for measuring the position and form of large mirror segments for solar collectors. The accuracy of the technique has been validated using a large Coordinate Measuring Machine (CMM) with results showing a measurement capability of better than 100 μm. The surface form and resulting slope errors of the parabolic troughs have been measured and the impact of the mirror support system determined. This paper contains the results of photogrammetry and CMM comparison with details of the measurements, their analysis and further related experimental results obtained using both measurement techniques.

In this work, the effects of casting orientation (horizontal, side, and vertical), section thickness (416mm) and composition (Cu, Mn) were investigated on the cooling rate, microstructure, and mechanical properties (tensile strength, yield strength, elongation, hardness) of hypereutectic ductile iron castings. Overall, horizontal castings were found to cool faster than side and vertical castings. Thermal analysis (using cooling curves) showed a wide difference among the four sections. Thinner sections exhibited significant undercooling and thereby carbide formation, leading to poor ductility. The combined effect of Cu and Mn showed an increase in the amount of pearlite to 82% and nodularity to 94% along with a reduction in nodule count to 323 and the amount of ferrite. Also, increased tensile strength (659MPa) and hardness (264 BHN) were observed along with a drop in ductility to 2.5% in 4mm thin section, helping offset carbide formation. Thermal analysis was found to be a useful tool in understanding the combined effect of orientation, thickness variations and processing parameters.

The recent emergence of materials for electronic systems that are capable of programmable self-destruction and/or bio/eco-resorption creates the potential for important classes of devices that cannot be easily addressed using conventional technologies, ranging from temporary biomedical implants to enviromentally benign environmental monitors to hardware secure data systems. Although most previous demonstrations rely on wet chemistry to initiate transient processes of degradation/decomposition, options in “dry transient electronic systems” could expand the range of possible uses. The work presented here introduces materials and composite systems in which sublimation under ambient conditions leads to mechanical fragmentation and disintegration of active devices upon disappearance of a supporting substrate, encapsulation layer, interlayer dielectric and/or gate dielectric. Examples span arrays of transistors based on silicon nanomembranes with specialized device designs to solar cells adapted from commercial components.

The current-time characteristic during high power pulsed magnetron sputtering is measured under identical conditions for seventeen different target materials. Based on physical processes such as gas rarefaction, ion-induced electron emission, and electron impact ionization, two test parameters were derived that significantly correlate with specific features of the current-time characteristic: (i) the peak current is correlated to the momentum transfer between the sputtered material and the argon gas, (ii) while the observed current plateau after the peak is connected to the metal ionization rate.

We consider the action of a group $G$ on the family $\mathcal{P}(G)$ of all subsets of $G$ by the right shifts $A\mapsto Ag$ and give the dynamical characterizations of thin, $n$-thin, sparse and scattered subsets.For $n\in\mathbb{N}$, a subset $A$ of a group $G$ is called $n$-thin if $g_0A\cap\dots\cap g_nA$ is finite for all distinct $g_0,\dots,g_n\in G$.Each $n$-thin subset of a group of cardinality $\aleph_0$ can be partitioned into $n$ $1$-thin subsets but there is a $2$-thin subset in some Abelian group of cardinality $\aleph_2$ which cannot be partitioned into two $1$-thin subsets. We eliminate the gap between $\aleph_0$ and $\aleph_2$ proving that each $n$-thin subset of an Abelian group of cardinality $\aleph_1$ can be partitioned into $n$ $1$-thin subsets.

This paper discusses the problem of the fatigue behaviour of small thickness welded joints using the implicit gradient method. Welds have been designed using 3D CAD and then subjected to finite element analysis, using the same computational procedure developed in the past for large thickness welded joints. In order to determine the Woehler curves for the various test series described in the literature, reference shall be made to either a monoaxial strength criterion or a multiaxial strength criterion capable of more efficiently evaluating the effect of a complex stress state while maintaining linear elastic behaviour for the material. The fatigue fault initiation zone is automatically evaluated by the computational procedure which indirectly returns the Woehler curve for the particular test. Application of the computational procedure to several test series taken from the literature has been performed for 2 mm thick sheets, predicting that the implicit gradient method may be applied to assess welded joints...

In situ lateral force microscopy (LFM) and X-ray photoelectron spectroscopy (XPS) were used to probe the lubrication behavior of an aqueous solution of poly(oxyethylene)-poly(oxypropylene)-poly(oxyethylene) (PEO-PPO-PEO) symmetric triblock copolymer on thin films of polypropylene (PP), polyethylene (PE), and cellulose. LFM experiments were carried out while the substrates were immersed in water and in solutions of the copolymer. The friction coefficient on PP and PE was reduced after adsorption from the PEO-PPO-PEO aqueous solution while the opposite effect was observed for cellulose surfaces. A critical normal loading force, at which the friction coefficient of the lubricated and unlubricated surfaces is equal, was identified and related to the affinity of the polymer with the substrate. Further experiments were performed to mimic practical operations involving lubricant addition during manufacturing and postprocessing removal. XPS was used to verify the presence of the lubricant on the polymeric substra...

This research examined the relative impact of a hoped-for, thin body and a feared, overweight body on weight-loss dieting (WLD) motivation. We hypothesised that the women most motivated to engage in WLD would report a higher similarity to, and a higher cognitive availability of, a feared, overweight body. In study 1, WLD motivation was operationalized as WLD intention and in study 2 as a food choice (chocolate bar versus low-fat snack bar). As expected, those most similar to the feared body and who had a highly available overweight body had the greatest intention to engage in WLD, and were more likely to choose a low-fat snack over a chocolate bar. The implications of our findings for future research as well as the development of eating pathology in college women are discussed. Copyright (C) 2011 John Wiley & Sons, Ltd.

WOS: 000470025500007, In this article, a novel wide band polarization and incident angle independent metamaterial absorber (MA) and energy harvesting applications which operates at C (4GHz-8 GHz) and X (8GHz-12 GHz) is proposed. The unit-cell of the proposed structure based on fractal circle loop. Four lumped resistors are mounted the structure to obtain a broad band absorption characteristics. Resistors increase the absorption characteristic of proposed MA significantly at mentioned frequency ranges. In addition, under favor of the resistors proposed MA can convert absorbed energy from incident wave to appearing power.

Objective: Many women show weight and body concerns that leave them vulnerable to body dissatisfaction, lowered self-esteem, psychological distress, and eating disorders. This study tested whether body satisfaction could be increased by means of evaluative conditioning. Design: In the experimental condition (n = 26), women with low and high body concern completed a conditioning procedure in which pictures of their bodies were selectively linked to positive social stimuli (pictures of smiling faces). Pictures of control bodies were linked to neutral or negative social stimuli (neutral and frowning faces). In a control condition (n = 28), low and high body concerned women underwent a procedure in which pictures of their own body and of control bodies were randomly followed by positive, neutral, and negative social stimuli. Main Outcome Measures: Changes in body satisfaction and self-esteem before and after the conditioning task. Results: Women with high body concern demonstrated an increase in body satisfaction and global self-esteem when pictorial representations of their own bodies were associated with positive stimuli that signaled social acceptance. Conclusion: A simple conditioning procedure increased body satisfaction in healthy, normal weight women who were concerned about their shape and weight.

Soft acoustic metamaterials utilizing mesoporous structures have been proposed recently as a means for tuning the overall effective properties of the metamaterial and providing better coupling to the surrounding air. In this paper, the use of silica aerogel is examined theoretically and experimentally as part of a compact soft acoustic metamaterial structure, which enables a wide range of exotic effective macroscopic properties to be demonstrated, including negative density, density near zero, and nonresonant broadband slow-sound propagation. Experimental data are obtained on the effective density and sound speed using an air-filled acoustic impedance tube for flexural metamaterial elements, which have been investigated previously only indirectly due to the large contrast in acoustic impedance compared to that of air. Experimental results are presented for silica aerogel arranged in parallel with either one or two acoustic ports and are in very good agreement with the theoretical model., This work is supported by the U.S. Office of Naval Research. M. D. G., V. M. G.-C. and J. S.-D. also acknowledge the support by the Spanish Ministerio de Economia y Competitividad, and the European Union Fondo Europeo de Desarrollo Regional (FEDER) through Project No. TEC2014-53088-C3-1-R. The authors wish to acknowledge Encarna G. Villora and Kiyoshi Shimamura for their help in aerogel fabrication and handling.

Underground Coal Gasification (UCG) is a process of gasifying coal in-situ to produce syn-gas. The gas thus produced, passes through the outflow channel that leads to the production well. As explained in part-I of this paper (Samdani et al., 2015), UCG can be divided in two distinct phases. The phase-I corresponds to initial vertical growth of the cavity and the output from phase-I model provides input to the phase-II model. This paper presents an unsteady state model for phase-II of UCG, wherein, the growth occurs in the horizontal direction towards the production well through the outflow channel. A compartment model, based on tracer studies performed on actual UCG cavity, is developed for phase-II of UCG. Here, the outflow channel is divided in small sections along the length, each consisting of rubble zone, void zone and roof at the top. This reduces the complexity caused by non-ideal flow patterns and changing sizes of different subzones inside the outflow channel. The subzones and the sections are linked appropriately, for mass and energy flow, to give overall performance of UCG. The proposed approach combines chemical reactions, heat and mass transfer effects, spalling characteristic and complex flow patterns to achieve meaningful results. In all, seven gas species, three solid species and eleven reactions are included. The simulation results such as variation in solid density, dynamics of different zones, exit gas quality are presented. The model is validated by comparing the predicted exit gas quality and that observed during similar laboratory scale experiments. Finally the results are also compared with pilot scale field-trials. This model along with the phase-I model provides a complete modeling solution for UCG process. (C) 2016 Elsevier Ltd. All rights reserved.

This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS applied materials and interfaces, copyright © American Chemical Society, after peer review and technical editing by the publisher and may be found at http://dx.doi.org/10.1021/acsami.5b04537 A 4-terminal architecture is proposed in which two thin active layers (

International audience; Reflective diffraction gratings employ periodic arrays of a given three dimensional structure to produce appropriate constructive and destructive interference to redirect an incident wave. Depending upon the angle of incidence, the thickness required for this structure can range from a fraction ofa wavelength to several wavelengths. Whilst such a thickness does not present a problem for optical applications it can make the diffraction grating very bulky for radio applications, notably in the lower frequency bands. This paper presents a new thin diffraction grating employing resonant structures, whose thickness is only 1/34th of a wavelength.