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A new technique for the correction of distorted current waveforms in the secondary windings of protective current transformers (CTs) is presented. The technique is based on the integration of the induced voltage in a tertiary winding. The exciting current is determined using a function that describes the magnetization process in the core, and by adding it to the distorted secondary current. In this way, a more faithful reproduction of the primary current wave is obtained. The initial magnetic flux in the core is determined by analogical integration of the voltage across the tertiary winding, from the pre-fault state up to the instant in which the current reaches 150% of the load current. Due to the large air gap length, the remanent flux in the core is ignored. [ABSTRACT FROM PUBLISHER]

This paper presents a novel metric for the quantification of memory effects in wireless transmitters and radio frequency power amplifiers driven by broadband-modulated signals. The proposed metric, labeled 'spectrum asymmetry index', is based on the spectrum asymmetry at the output of the transmitter/power amplifier (PA). The effectiveness and reliability of the proposed metric are experimentally validated using a Doherty PA and a class AB PA driven by WCDMA signals having various bandwidths and power levels. The experimental results show that the proposed metric is consistent with the previously reported memory effects intensity metric for bandwidths up to 20 MHz since both metrics predict increasingly strong memory effects as the signal bandwidth or average power increases. However, experimental validation with signals having wider bandwidths (up to 40 MHz) illustrates the robustness and advantage of the proposed metric compared to its state of the art counterpart. Indeed, for these test conditions, the spectrum asymmetry index is able to predict the memory effects strengthening, while the memory effects intensity metric is unable to track this trend. It is also shown that the proposed metric can be used to compare the memory effects strength in PA prototypes. In fact, comparing the spectrum asymmetry index of two different power amplifiers provides a reliable information on the relative strength of their memory effects. Furthermore, the proposed metric is derived directly from the measured output signal without requiring cancelation of the static nonlinearity. This presents an additional major advantage compared to previously reported methods for memory effects quantification in transmitters and power amplifiers driven by wideband-modulated signals. [ABSTRACT FROM AUTHOR]

Highlights: [•] A multi-physics thermo-chemical–mechanical modeling of nitriding was developed. [•] A scale transition model accounts for the coupling between phases. [•] The unknown inputs are evaluated by an inverse identification method. [•] The phase distributions, residual stresses and distortions are computed at once. [•] FEM calculations were developed to simulate nitriding of complex geometries. [ABSTRACT FROM AUTHOR]

This research paper is related to the devaluation of rupee in India. After 1947, India has faced two major financial crises and two consequent devaluations of the rupee. These crises were in 1966 and 1991 and now in 2013 the situation is also parallel and very destructive, as I plan to show in this paper, they had similar causes. The price of 16 Ananas is 1 rupee in 1947. The demand for decimalization existed for over a century. Sri Lanka decimalized its rupee in 1869. The Indian Coinage Act was amended in September 1955 for the adoption of a decimal system for coinage .it, however, was now divided into 100 'Paisa' instead of 16 Ananas or 64 Pice. In 1947 the value of rupee was one against the US dollar and in 1966 was 7.5, and in 1990 was 17.01 but it is 63.54 at November 2013. The Indian rupee touched a lifetime low of 68.85 against the US dollar on August 28, 2013. The rupee plunged by 3.7 percent on the day in its biggest single-day percentage fall in more than two decades. There is no denying that India is not the only emerging market experiencing a rapid decline in its currency's value. Since January 2013, the rupee has lost more than 20 percent of its value, the biggest loser among the Asian currencies. In this research we will learn about the reasons, causes and effects, and suggestions to evaluate the impact of the falling rupee on the Indian economy. [ABSTRACT FROM AUTHOR]

We report pair distribution function studies on the relationship between the metal-insulator transition (MIT) and lattice distortions in pure and Ti-substituted bilayer Ca 3 Ru 2 O 7 . Structural refinements performed as a function of temperature, magnetic field and length scale reveal the presence of lattice distortions not only within but also orthogonal to the bilayers. Because of the distortions, the local and average crystal structure differ across a broad temperature region extending from room temperature to temperatures below the MIT. The coexistence of distinct lattice distortions is likely to be behind the marked structural flexibility of Ca 3 Ru 2 O 7 under external stimuli. This observation highlights the ubiquity of lattice distortions in an archetypal Mott system and calls for similar studies on other families of strongly correlated materials., (© 2022 IOP Publishing Ltd.)

Electron diffraction patterns unavoidably contain in-plane distortions introduced by electromagnetic lens systems. Geometric correction of different distortion types allows the accuracy of lattice parameter determination to be improved in 3D electron diffraction data., (© Tatiana Gorelik 2022.)

Determination of lattice parameters from 3D electron diffraction (3D ED) data measured in a transmission electron microscope is hampered by a number of effects that seriously limit the achievable accuracy. The distortion of the diffraction patterns by the optical elements of the microscope is often the most severe problem. A thorough analysis of a number of experimental datasets shows that, in addition to the well known distortions, namely barrel-pincushion, spiral and elliptical, an additional distortion, dubbed parabolic, may be observed in the data. In precession electron diffraction data, the parabolic distortion leads to excitation-error-dependent shift and splitting of reflections. All distortions except for the elliptical distortion can be determined together with lattice parameters from a single 3D ED data set. However, the parameters of the elliptical distortion cannot be determined uniquely due to correlations with the lattice parameters. They can be determined and corrected either by making use of the known Laue class of the crystal or by combining data from two or more crystals. The 3D ED data can yield lattice parameter ratios with an accuracy of about 0.1% and angles with an accuracy better than 0.03°., (© Petr Brázda et al. 2022.)

Of great concern is the existence of instructional manuals circulating online that provide pedophiles with guidance on how to sexually abuse children. To better understand the role this material may play in the exploitation of children, the United States Marshals Services Behavioral Analysis Unit conducted a qualitative analysis on the content of all known pedophile manuals. From the cumulative content of these manuals we derived a model of victim selection and identified specific strategies used by this population to harm children. The manuals reveal that although external situational factors are given consideration during victim selection, the internal vulnerabilities of the victim are emphasized for active exploitation. The graphic content found within the documents and the ability to obtain them anonymously exacerbate the danger these manuals pose by reinforcing cognitive distortions, fostering networking opportunities, and normalizing the sexual abuse of children. The "education" provided in the manuals may bolster pedophilic identification as well as increase criminal efficacy. In the current paper we present important insights we obtained about the mentality and methodologies of pedophiles and other individuals interested in sexually exploiting children. [ABSTRACT FROM AUTHOR]

The observation of structural distortions in complex oxides is becoming more important in order to explain their macroscopic behavior. X-ray photoelectron diffraction is an excellent technique to study the crystal structure and potentially observe oxygen distortions in an element-specific fashion. Its surface-sensitive character opens up the possibility to perform experiments on ultra-thin films without probing the substrate underneath. For BaBiO 3 thin films, for example recent experimental results point towards a suppression of an oxygen breathing mode with decreasing film thickness resulting in a decreased energy band gap. As another example, a nontrivial electronic band structure is predicted for [111]-bilayers of LaMnO 3. However, the likely presence of a Jahn–Teller distortion would suppress the topological phase. Here, the working principle of x-ray photoelectron diffraction is described and the data analysis required afterwards is discussed. X-ray photoelectron diffraction interference patterns are obtained for various thicknesses of BaBiO 3 and LaMnO 3 thin films. Experimental results are compared with multiple-scattering simulations. Although, indications for the structural distortions are observed, we discuss limitations of the technique in quantifying the displacement of the oxygen atoms. • General concepts and data analysis of x-ray photoelectron diffraction (XPD). • Element specific and surface sensitive study of the crystal structure by XPD. • Interpreting XPD patterns with the help of multiple-scattering simulations. • Characterizing oxygen octahedra distortions in BaBiO 3 and LaMnO 3 [ABSTRACT FROM AUTHOR]

Abstract: The mechanical behavior of soft matter is characterized by large shape changes, often accompanied by small changes of elastic energy; non-linear elasticity, with large, inhomogeneous, and anisotropic distortions, that may evolve in time, proved to be an effective modeling tool for many of such soft materials. Here, we deal with the definition of an appropriate strain measure, called the elastic metric, upon which the elastic energy density can be defined. Moreover, we discuss two key issues about distortions: one deals with the notion of compatible distortions, that is, distortion fields yielding a global configuration without any change of the elastic energy; the other concerns the symmetries of the material responses. We also present few selected examples of non-linear, anisotropic, elastic response where distortions play a key role. [Copyright &y& Elsevier]

Abstract: Electrochemical impedance spectroscopy for lithium ion batteries has recently gained increasing attention due to its ability of non-invasive evaluation of important electrochemical parameters. Commonly used three-electrode test cells, however, proved unreliable due to asymmetric current line distributions, causing severe distortions of impedance spectra. Finite element method (FEM) simulations can visualize these current lines at different frequencies and simulate impedance spectra at given geometries. By applying FEM simulations to a recently developed coaxial impedance test cell, limiting conditions for reliable impedance measurements could be identified. Using a reference electrode in coaxial position yields sufficiently reliable results as long as the electrode misalignment is small compared to the electrolyte thickness and edge effects are prevented. [Copyright &y& Elsevier]

New tables of irreducible representations (IRs) are introduced for the 230 crystallographic space groups (SGs) in three-dimensional space, at both special and non-special k vectors, and for their extensions to (3 + d)-dimensional superspace (`superspace-extended SGs' or SSESGs). Neither a tabulation of SG IR matrices for non-special k vectors nor a tabulation of SSESG IR matrices for d > 1 have been previously published. These tabulations are made possible by a new form in which the IR matrices of SGs are separated as a product of a translation part T and a point-operation part P, and where the IR matrices of SSESGs are separated as a product of a phase-shift part Q and a point-operation part P s. Both T and Q have a simple prescribed form that does not need to be tabulated. Also, the new IR matrices are in a convenient block form which allows one to see by inspection which parts of the matrices and the associated order parameters belong to which arm of the star of k. In addition to complex IR matrices, real physically irreducible representation (PIR) matrices are tabulated. The new IR and PIR tables are available on the ISO-IR website (http://stokes.byu.edu/iso/irtables.php) in both convenient human-readable and computer-readable forms. [ABSTRACT FROM AUTHOR]

Copyright of Bucharest University Annals - Law Series is the property of CH Beck Publishing House and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: To correct distortions caused by eddy currents induced by large diffusion gradients during high angular resolution diffusion imaging without any auxiliary reference scans. Materials and Methods: Image distortion parameters were obtained by image coregistration, performed only between diffusion-weighted images with close diffusion gradient orientations. A linear model that describes distortion parameters (translation, scale, and shear) as a function of diffusion gradient directions was numerically computed to allow individualized distortion correction for every diffusion-weighted image. Results: The assumptions of the algorithm were successfully verified in a series of experiments on phantom and human scans. Application of the proposed algorithm in high angular resolution diffusion images markedly reduced eddy current distortions when compared to results obtained with previously published methods. Conclusion: The method can correct eddy current artifacts in the high angular resolution diffusion images, and it avoids the problematic procedure of cross-correlating images with significantly different contrasts resulting from very different gradient orientations or strengths. J. Magn. Reson. Imaging 2013;37:1460-1467. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: A thermodynamically consistent modeling of the non-linear multiphysics behavior of ionic polymers is presented and discussed. A key ingredient of the model is the treatment of the electrically induced deformations, resulting in a large bending motion when ionic polymers are employed in IPMCs (Ionic Polymer-Metal Composites). With specific reference to the mechanics, the position of the linear models for ionic polymers is discussed and set within a formalized linearization procedure. A set of numerical experiments is developed, showing the capability of the model to capture the fundamental features of the actuation mechanism. [Copyright &y& Elsevier]

The effects of eddy currents on the design value of magnetic field in accelerators are investigated analytically. A program is developed for calculation of magnetic field distortions caused by eddy currents. The numerical results are given for the accelerator in Yerevan Physics Institute, if it will be used to accelerate the ions. [ABSTRACT FROM AUTHOR]

The paper interprets the growth experience of three Western European countries (France, Germany and the UK) and three Central-Eastern European economies (the Czech Republic, Hungary, and Poland) through the lens of the neoclassical growth model. It combines the methodologies of Development Accounting (Caselli, F. 2005. "Accounting for Cross-Country Income Differences." In Handbook of Economic Growth, Chapter 9, 679-741.) and Business Cycle Accounting (Chari, V. V., P. J. Kehoe, and E. R. McGrattan. 2007. "Business Cycle Accounting." Econometrica 75 (3): 781-836.) to calculate distortions - "wedges" - in production efficiency, and in the labor and capital markets. The exercise sheds light on the extent and evolution of factor market distortions between 1996 and 2009. The main result of the paper is that capital and labor market distortions do not explain income differences across the two country groups, but are important to understand income differences within groups. In addition, observed labor and capital taxes are related to the measured wedges, but significant unexplained components remain. Reducing labor and capital market distortions would lead to significant output gains in all countries. [ABSTRACT FROM AUTHOR]

Total factor productivity (TFP) in Latin America has declined relative to the US since the mid-1970s. This paper applies a comparable methodology to firm-level data of ten Latin American countries to quantify the heterogeneity of firm productivity and the extent to which resource misallocation can explain lower aggregate TFP. In general, productivity heterogeneity and resource misallocation are found to be much larger than in the US. Achieving an efficient allocation of resources could boost manufacturing TFP between 41% and 122% depending on the countries and years considered. We also find that difficulty in access to capital and restrictive labor regulations explain distortions faced by firms. [ABSTRACT FROM AUTHOR]

This article studies a model with physical and human capital accumulation and varieties. The model includes several distortions: duplication effects, spillovers, creative destruction, surplus appropriability, and an erosion effect. We show that the duplication effect in R&D is essential to make the model replicate several stylized facts linked with R&D. We evaluate the distance to the optimal solution, comparing the strength of each distortion. [ABSTRACT FROM AUTHOR]

Abstract: A question which has not been addressed so far in the analysis of the twisting motion of the heart, relates to the existence of any advantages in energetic expenditure due to differential contractile properties across the wall of the ventricles. The question is addressed in this paper by a highly simplified analytical model of the ventricular cavity, based on a cylindrical geometry and set in the context of the linear theory of elasticity; however, the anisotropy of contraction is also taken into account. It is concluded, that when oppositely directed spirals of fibres in the internal and external layers of the cylinder keep the torsion within suitable limits, i.e. mimicking the biological context, a smaller energetic expenditure is related to a transmural pattern of contraction which is not uniform, and presents a larger epicardial contraction. [Copyright &y& Elsevier]

This study examined inexperienced listeners' perceptions of children's naturally produced /r/ sounds with reference to levels of accuracy determined by consensus between two expert clinicians. Participants rated /r/ sounds as fully correct, distorted or incorrect/non-rhotic. Second and third formant heights were measured to explore the relationship between acoustic cues and perceptual judgments. Inexperienced listeners' agreement was greater for correct productions than for distorted or incorrect/non-rhotic productions. In addition, inexperienced listeners' differentiation of intermediate versus fully incorrect /r/ had lower sensitivity and specificity relative to an acoustically defined threshold than experienced listeners' classification. These findings are consistent with results of previous studies highlighting the difficulty in identifying gradations of correctness in misarticulated /r/, and they suggest that this ability may be influenced by clinical experience. Additionally, all listeners were noted to be more consistent in rating vocalic /r/ than consonantal /r/. Implications for clinician training and treatment planning are discussed. [ABSTRACT FROM AUTHOR]

The ability to accurately predict residual stresses and resultant distortions is a key product from process assembly simulations. Assembly processes necessarily consider large structural components potentially making simulations computationally expensive. The objective herein is to develop greater understanding of the influence of friction stir welding process idealization on the prediction of residual stress and distortion and thus determine the minimum required modeling fidelity for future airframe assembly simulations. The combined computational and experimental results highlight the importance of accurately representing the welding forging force and process speed. In addition, the results emphasize that increased CPU simulation times are associated with representing the tool torque, while there is potentially only local increase in prediction fidelity. [ABSTRACT FROM AUTHOR]

Problems of statistical forecasting of time series under distortions of hypothetical models are considered. A classification scheme of the typical distortions of time series is presented and mathematical descriptions of distortions are given. Robustness characteristics for the mean square risk of forecasting (the risk unstability coefficient and the δ-admissible distortion level) are evaluated for the regression time series under outliers and functional distortions. New robust forecasting statistics are constructed. The theoretical results are illustrated by numerical experiments. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to characterize the levels of artifacts and distortions of titanium applicators on 3.0-Tesla magnetic resonance imaging (MRI). Methods and Materials: Fletcher-Suit-Delclos-style tandem and ovoids (T&O) and tandem and ring applicator (T&R) were examined. The quality assurance (QA) phantoms for each applicator were designed and filled with copper sulphate solution (1.5 g/l). The artifacts were quantified with the registration of corresponding computed tomography (CT) images. A favorable MR sequence was searched in terms of artifacts. Using the sequence, the artifacts were determined. The geometric distortions induced by the applicators were quantified through each registration of CT and MRI without applicators. The artifacts of T&O were also evaluated on in vivo MRI datasets of 5 patients. Results: T1-weighted MRI with 1-mm slice thickness was found as a favorable MR sequence. Applying the sequence, the artifacts at the tandem tip of T&O and T&R were determined as 1.5 ± 0.5 mm in a superior direction in phantom studies. In the ovoids of T&O, we found artifacts less than 1.5 ± 0.5 mm. The artifacts of a T&O tandem in vivo were found as less than 2.6 ± 1.3 mm on T1-weighted MRI, whereas less than 6.9 ± 3.4 mm on T2-weighted MRI. No more than 1.2 ± 0.6 mm (3.0 ± 1.5 mm) of distortions, due to a titanium applicator, were measured on T1-weighted MRI (T2-). Conclusion: In 3.0-Tesla MRI, we found the artifact widths at the tip of tandem were less than 1.5 ± 0.5 mm for both T&O and T&R when using T1-weighted MRI in phantom studies. However, exclusive 3.0-Tesla MRI-guided brachytherapy planning with a titanium applicator should be cautiously implemented. [ABSTRACT FROM AUTHOR]

In this paper, long arcs in free air are investigated. A long arc was induced in the high-power test laboratory at FGH-Mannheim, Germany. From the recorded arc data, the features of the arc were derived and analyzed, including elongation effects associated with these arcs. Based on this analysis of a real arc, a new “AirArc” static arc model, including the length variations, was derived and incorporated into the Alternate Transients Program–Electromagnetic Transients Program software package in which it was simulated. The arc is modeled as a current-dependent voltage source with a characteristic-distorted rectangular voltage that elongates nonlinearly over time. Fault arcs are a significant source of harmonics that distort other voltages and currents in the network. The time-domain and spectral-domain features of the simulated arc are compared with those of the real arc. The assessment of transient processes during arcing faults was carried out using the discrete wavelet transform. [ABSTRACT FROM AUTHOR]

This work extends the mathematical formulation of the iterative-field-matrix method for observed data from the near-field region of a Perfect Electric Conductor. The method is used as a diagnosis tool for reflector antennas, to determine the positions and extent of distortions from their idealized shapes. The new formulation is tested on a reflector antenna with several significant bumps, and excellent results are achieved. This work also presents an example where the Method of Moments is used to generate the synthetic data and the inversion is performed using Physical Optics. Such a configuration ensures that the forward model is unbiased with respect to the inversion model, demonstrating that the new formulation is also robust for these realistic scenarios. [ABSTRACT FROM PUBLISHER]

The paper gives an answer to the questions: if the maritime area of Croatia (territorial sea and continental shelf) is involved, which is the best Lambert conic conformal map projection for the territory of Croatia? Numerical Realization demanded the northernmost and the southernmost coordinates on the land and sea of Croatia. Since the coordinates of the southernmost point on the sea, i.e. those on the line of the continental shelf, had never been calculated before, it had to be done in this work. Thereafter eight variants of conic conformal map projections with respect to the distribution of linear distortions were analyzed. Each variant was clearly defined, and they differ in the constants of projection, which were obtained by setting initial conditions. On the basis of performed research the best Lambert conic conformal map projection for the territory of Croatia including its territorial sea and continental shelf was proposed. [ABSTRACT FROM AUTHOR]

This paper introduces a new, accurate, and complexity-reduced three-nonlinear-box model that is suitable for the behavioral modeling and digital predistortion (DPD) of power amplifiers (PAs) exhibiting memory effects. This model is composed of a look-up table (LUT), a memory polynomial (MP), and an envelope MP (EMP), which are all connected in parallel, and it is termed as Parallel-LUT-MP-EMP (PLUME). The PLUME model's performance is experimentally assessed using a highly nonlinear Doherty PA driven by a multicarrier wideband code division multiple access signal. A comparison is held between the PLUME model and different state-of-the-art models reported in the literature, such as the MP model, the parallel twin nonlinear two-box model, and the generalized MP (GMP) model. The experimental results, in both behavioral modeling and DPD applications, demonstrate that the proposed PLUME model outperforms the first two models. However, it shows the same accuracy as the GMP model but with an approximately 45% reduction in the number of coefficients. This significant decrease in coefficients considerably reduces the model computational complexity. Another comparison of the resources utilized for field programmable gate array implementation of the PLUME model and the GMP model is performed, which reveals that the PLUME model uses much fewer resources than the other model. [ABSTRACT FROM AUTHOR]

Concerned about national grain self-sufficiency and rural household incomes, in 2004 China announced that it was planning to reverse its longstanding policy of taxing farm households and instead began to provide them with subsidies. Over the past five years, annual announcements have trumpeted rises in subsidies. Surprisingly, despite the historic turnaround of policy and the likely implication of this subsidy policy to China's grain economy, there has been no household-level survey-based research that has sought to understand the effect of China's subsidy programme on household behaviour. Using data from a national survey of more than 1000 households, we examine in detail a number of different dimensions of the subsidy programme. According to the survey-based findings, we have shown that although agricultural subsidies per farm are low, on per unit of cultivated area basis or total amount of budget, the subsidies are high. Almost all producers are receiving them. Subsidies are mostly being given to the land contractor, not the tiller. Most importantly, the subsidies appear to be nondistorting. No matter if we look at descriptive statistics in tables, scatter plots or regression analyses, there is no evidence that grain subsidies are distorting producer decisions in terms of grain area or input use decisions. [ABSTRACT FROM AUTHOR]

Abstract: Structural features of polyoxometalates (POMs) —versatile inorganic clusters of academic and technological interest— are discussed in the present article. POMs are, in general, very regular structures presenting a high symmetry in most cases. Distortions are, however, important for some electronic and magnetic properties. We herein discuss some particular geometric features that are crucial for the theoretical treatment and comprehension of well-known experimental phenomena. For instance, we have been able to understand and rationalize the geometrical distortions present in molybdenum POMs. Moreover, we can affirm that these geometrical distortions are caused by a pseudo Jahn Teller effect. In what concerns NMR chemical shifts, we present a discussion on the importance of geometry for the correct description of the signals and the key role played by the interatomic distances. Finally, a study on the adsorption of Keggin clusters on silver surfaces shows how the POM structure looses its regular shape to adapt to that new situation. [Copyright &y& Elsevier]

This paper focuses on the errors affecting the estimation of power switching losses in power semiconductor devices based on integration of the voltage by current product. It is shown that the measured waveforms are not simply delayed by the probes, but some overshoots and distortions are due to the probes, which may not easily be corrected. These effects are the source of errors, particularly in fast transients. This paper shows analyses of simulation and measurements, including probe models. [ABSTRACT FROM PUBLISHER]

This paper presents a numerical simulation for examining temperature fields, residual stresses, and distortions in multi-pass welding of a pipe-flange joint. A sequentially coupled transient non-linear thermo-mechanical three-dimensional finite-element model is developed to simulate four-pass tungsten inert gas welding process. An ANSI class 300{#} flange is welded with a 6 mm thick, 200 mm long, and 100 mm nominal diameter pipe, using a single V-groove butt joint with a 1.2 mm root opening. Goldak's double ellipsoidal model is used for the weld heat source, and inactive element addition technique is used for the addition of weld filler elements. Axial and hoop residual stresses and out-of-plane distortions along the flange face are plotted. In addition, welding start and end effects are discussed. [ABSTRACT FROM AUTHOR]

This work presents an electric field gradient and magnetic hyperfine field study, in the AgCrO multiferroic with triangular spin lattice. The temperature dependence of the electric field gradient ( efg) and magnetic hyperfine field ( mhf) at Cr site was studied at isolde via perturbed angular correlation measurements with the In probe, at room temperature and below the Néel temperature ( T ≤ 21 K) down to 12 K. The results show the presence of two distinct local environments. One axial symmetric efg with a very low mhf, and a non axially symmetric efg with a much higher one. The temperature dependences of mhf magnitude and of the angle between the mhf and the principle component of the efg are investigated. [ABSTRACT FROM AUTHOR]

Distortions in the marginal region during manufacture are detrimental to the long-term success of fixed dental prostheses (FDPs). The aim of the present in vitro study was to evaluate changes in marginal fit because of the veneering process of four-unit FDPs made from different zirconia materials. Two groups of FDPs with 10 specimens each were machined from white body zirconia blanks (VITA In-Ceram YZ Cubes, KaVo Everest ZS-Blanks) by means of computer-aided design/computer-aided manufacturing systems and subsequently sintered to their final density. The marginal and internal gaps of the frameworks were determined using a replica technique. Afterwards, frameworks were veneered with the recommended ceramics (VITA VM9, GC Initial Zr), and fitting accuracy was evaluated again. Statistical analyses were performed by Student’s t-test with the level of significance chosen at 0·05. With one framework/veneering system (Everest ZS-Blanks/Initial Zr), both marginal gap ( P = 0·019) and internal gap ( P = 0·001) at the premolar retainer were significantly affected by the veneering process. The resulting distortions were directed towards the lumina of the retainers and the mean values of the measured gaps decreased by about 23·8 μm (marginal gap) and 27·3 μm (internal gap). For the other system (In-Ceram YZ Cubes/VM9), no distortions because of the veneering were found. The veneering of zirconia restorations may lead to significant changes in the marginal fit, while the combination of core and veneering material used influences the resulting distortions. [ABSTRACT FROM AUTHOR]

The article discusses the cultural matrix of distorted representations of therapists in many films in the U.S. The meaning of transferential passion of clinical realm and in the films are both discussed as well as the violations of medical boundaries of the big screen. Thus, the contemporary films are used to illustrate and mark the representations of therapists within the cinematic story.

Copyright of Revista Virtual Universidad Católica del Norte is the property of Revista Virtual Universidad Catolica del Norte and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We present a mathematical method for identifying, separating and quantifying the 3D significant distortions. Measurement of a gas quenched C-ring type sample is performed by a Coordinate Measuring Machine (CMM). Quenching simulation is done with the commercial software Forge 2008 TTT®. After comparisons, we notice that the distortions and their tendencies are the same but not exactly the amplitudes. We only focus on distortions which have a physical origin, like the pincers opening, often observed in the literature. As a first explanation, we underline the role of phase transformations and volume dilatation of the steel during quenching. [ABSTRACT FROM AUTHOR]

This article mainly discusses whether the introduction or increase of tourism taxation should be addressed through specific or general indirect taxation. With this aim, the paper describes the concept of tourism taxes and presents the several reasons that back their use. The paper also offers some numerical exercises comparing the effects of specific and general tourism taxation in Spain, a developed country with a sizeable tourism industry. The article suggests that both specific and general taxes on tourism would be able to yield improvements in terms of revenues and internalization of costs without hampering the economy. Yet, in comparative terms, general indirect taxes may be a more feasible, equitable and neutral way to obtain tax revenues from tourism activities. [Copyright &y& Elsevier]