Proper Basis Research Articles

Multimode Raman light-atom interface in warm atomic ensemble as multiple three-mode quantum operations

We analyse the properties of a Raman quantum light-atom interface in long atomic ensemble and its applications as a quantum memory or two-mode squeezed state generator. We consider the weak-coupling regime and include both Stokes and anti-Stokes scattering and the effects of Doppler broadening in buffer gas assuming frequent velocity-averaging collisions. We find the Green functions describing multimode transformation from input to output fields of photons and atomic excitations. Proper mode basis is found via singular value decomposition for short interaction times. It reveals that triples of modes are coupled by a transformation equivalent to a combination of two beamsplitters and a two-mode squeezing operation. We analyse the possible transformations on an example of warm rubidium-87 vapour. The model we present bridges the gap between the Stokes only and anti-Stokes only interactions providing simple, universal description in a temporally and longitudinally multimode situation. Our results also provide an easy way to find an evolution of the states in a Schrödinger picture thus facilitating understanding and design.

The Supreme Court Should Grant Certiorari in FTC v. McWane

Exclusive dealing is the last vestige of the pre-economic era of antitrust. And it shows. The Supreme Court’s decision in GTE Sylvania nearly 40 years ago was the turning point for the evolution of modern antitrust law in the United States because it made clear “that the analysis of economic effects provided the proper basis for evaluating conduct under the antitrust laws.” In the area of vertical restraints in particular, the critical lesson that has emerged from the economic revolution in antitrust law has been that such conduct must not be condemned without economic evidence of harm to competition. The Supreme Court should grant certiorari in FTC v. McWane because, unfortunately, it is a vivid demonstration of the fact that exclusive dealing law remains untouched by the intellectual revolution in antitrust doctrine since the Supreme Court’s decision in GTE Sylvania. The Federal Trade Commission’s analysis in FTC v. McWane, and thus the Eleventh Circuit opinion, are not only in significant tension with the modern antitrust approach to vertical restraints, they reject it altogether. McWane presents a unique and timely opportunity for the Supreme Court to bring exclusive dealing law in line with modern antitrust law and economic analysis, to recalibrate the doctrine to focus on harm to competition, and to provide guidance to lower courts with respect to the application of rule of reason analysis in cases involving exclusive dealing arrangements.

Intelligent bearing fault signature extraction via iterative oscillatory behavior based signal decomposition (IOBSD)

A typical vibration signal from a defective bearing is composed of fault-induced transients (i.e., fault signature), resonance, multiple vibration interferences and background noise. Extracting the fault-induced transients from such signals is the primary goal for bearing fault diagnosis. This paper proposes an intelligent oscillatory behavior based signal decomposition (OBSD) method for this purpose. The OBSD technique exploits both the signal separation capability of morphological component analysis (MCA) and the basis creation potential of tunable Q-factor wavelet transform (TQWT). To generate proper bases for each individual signal component, the Q-factor determination and tuning strategies for the TQWT are developed in this study. In the presence of multiple interferences, one-time OBSD may not be sufficient to extract fault feature successfully. As such, an iterative OBSD (IOBSD) procedure is proposed. With the proposed method, a vibration signal can be decomposed into three signal components, i.e., low-oscillation component (fault signature presenting non-oscillation), high-oscillation component (interferences manifesting sustained oscillation) and residual (noise), according to their oscillatory behaviors. Bearing faults can then be reliably detected. The main features of the proposed method include: (1) it can remove in-band interference and noise that cannot be removed by the widely used frequency-based approaches, as it is frequency-independent in nature, (2) it can extract fault signatures from heavily interference-obscured signals without filtering the signals, and (3) it does not require the prior information of the signals. With these features, the IOBSD method can substantially reduce human involvement and facilitate its implementation in a fault detection expert system, particularly in an environment with various interferences. The IOBSD method has been favorably compared with one of the popular filtering techniques, i.e., SK method. The effectiveness of the proposed method has also been tested by simulation and experiments.

Hiding data in compressive sensed measurements: A conditionally reversible data hiding scheme for compressively sensed measurements

Most of the real-world signals we encounter in real-life applications have low information content. In other words, these signals can be well approximated by sparse signals in a proper basis. Compressive sensing framework uses this fact and attempts to represent signals by using far fewer measurements as compared to conventional acquisition systems. While the CS acquisition is linear, the reconstruction of the signal from its sparse samples is nonlinear and complex. The sparse nature of the signal allows enough room for some additional data sequence to be inserted and exactly recovered along with the reconstructed signal. In this study, we propose to linearly embed and hide data in compressively sensed signals and nonlinearly reconstruct both of them using a deflationary approach. We investigate the embedding capacity as a function of signal sparsity and signal compression, as well as the noise sensitivity of the proposed algorithm.

Detwinning of face-centered cubic deformation twins via the correspondence matrix approach

Transformation of dislocations during detwinning of face-centered cubic materials is shown. The analysis is based on the correspondence matrix method and the results are additionally presented on the stereographic projection of a double twin/matrix lattice. The results show the existence of three different detwinning modes. One associated with reverse twinning mode and two others associated with pseudo-reverse twinning modes. It was found that only the reverse twinning mode is eventually able to cancel physical consequences of face-centered cubic deformation twinning (change of crystal shape and crystal orientation) including the effect of dislocation hardening (glissile to sessile dislocation transition). The other two detwinning modes lead to further dislocation hardening of a de-twinned crystal by instead producing very sessile dislocation configurations. The differences in physical consequences between the different detwinning modes will be effectively enhanced during further deformation processes involving higher order detwinning, except for the effect of crystal orientation. The obtained results and the elaborated analytical methods may serve as a proper geometrical basis for further experimental procedures involving transmission electron microscopy techniques to study de-twinned structures of dislocated face-centered cubic materials.

Reasons of Law: Dworkin on the Legal Decision

Ronald Dworkin once identified the basic question of jurisprudence as: ‘What, in general, is a good reason for a decision by a court of law?’ I argue that, over the course of his career, Dworkin gave an essentially sound answer to this question. In fact, he gave a correct answer to a broader question: ‘What is a good reason for a legal decision, generally?’ For judges, officials of executive and administrative agencies, lawyers, non-governmental organizations, and ordinary subjects acting in the variety of legal contexts, Dworkin identified the proper basis for a legal decision, and its implications for the form of well-conducted legal reasoning. Dworkin's stance on the above questions can be characterised by two theses. I defend his view by substantiating each. The result is agnostic about the viability of other aspects of Dworkin's legal theory, as it focuses on the grounds of proper legal decision-making. Whatever the fate of his other philosophical views, Dworkin's jurisprudence includes a clear-headed, though morally challenging, understanding of the proper basis for decisions of law.

Evaluating Formation-Fluid Properties During Sampling-While-Drilling Operations

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 173152, “Evaluating Formation-Fluid Properties During Sampling- While-Drilling Operations,” by K. Indo, J. Pop, K. Hsu, and S. Ossia, Schlumberger; G.-L. Atzeni and A. Malossi, Eni; and V. Agarwal, A. Garcia-Mayans, S. Paul, J. Varughese, and S. Haq, Schlumberger, prepared for the 2015 SPE Drilling Conference and Exhibition, London, 17–19 March. The paper has not been peer reviewed. Recent experience with a newly introduced sampling-while-drilling service has shown that it is possible to make reliable downhole formation-fluid-property estimates during sampling-while-drilling operations. These property and contamination estimates facilitate the management of the entire while-drilling sampling process by aiding sample-capture decisions and allowing the best possible use of the sample bottles currently available on a drilling bottomhole assembly. Moreover, the contamination estimates, together with the real-time fluid-property estimates, enable prediction of the uncontaminated-fluid properties. Introduction If performed during drilling (when filtrate invasion is not fully developed), fluid scanning—where formation fluid is pumped and analyzed within the sampling-while-drilling tool without taking a sample—affords the opportunity to characterize the formation fluid at potential sampling depths before committing sample chambers. The success of such an approach depends on how completely the in-situ fluid can be characterized and how free of contamination the assessed properties are. By use of downhole optical spectrometry, it has been shown recently that it is possible to estimate in real time at least the following formationfluid properties: fluid color and type, hydrocarbon composition at various levels, carbon dioxide (CO2) content, gas/oil ratio (GOR), formation volume factor (FVF), and asphaltene content. Other measurements such as pressure, temperature, pressure gradients, and fluid density and viscosity enhance the characterization. Although not replacing pressure/volume/temperature (PVT) laboratory measurement of fluid properties, this list allows the fluid to be characterized sufficiently well to determine the fluid type and to differentiate between fluids at different spatial locations. This capability becomes important when deciding which fluid to sample, whether to recover a fluid sample, and whether another sampling run should be undertaken. The process of differentiating between fluids becomes increasingly difficult as the level of contamination of the sampled fluid increases; the proper basis for comparison is, ideally, a contamination-free (clean) fluid. If estimates of uncontaminated-fluid properties were available during drilling operations, the allocation of samples to fluids having the highest recovery priority would be expedited.

Compressive sensing of full wave field data for structural health monitoring applications.

Numerous nondestructive evaluations and structural health monitoring approaches based on guide waves rely on analysis of wave fields recorded through scanning laser Doppler vibrometers (SLDVs) or ultrasonic scanners. The informative content which can be extracted from these inspections is relevant; however, the acquisition process is generally time-consuming, posing a limit in the applicability of such approaches. To reduce the acquisition time, we use a random sampling scheme based on compressive sensing (CS) to minimize the number of points at which the field is measured. The CS reconstruction performance is mostly influenced by the choice of a proper decomposition basis to exploit the sparsity of the acquired signal. Here, different bases have been tested to recover the guided waves wave field acquired on both an aluminum and a composite plate. Experimental results show that the proposed approach allows a reduction of the measurement locations required for accurate signal recovery to less than 34% of the original sampling grid.

Aerodynamic Load Estimation from Virtual Strain Sensors for a Pliant Membrane Wing

An approach has been developed to use the strain sensed in a membrane wing to estimate aerodynamic loads. Through experimental and theoretical correlation of membrane strain state due to a normally distributed load, the pressure over the surface of the wing was estimated. Elastic deformations and strains of the membrane wing were measured in a low-speed wind tunnel using digital image correlation. Simultaneously, aerodynamic loads were measured using a six-component load cell, inclinometer, and pitot tube. Digital image correlation displacement measurements were used to form a reduced-order model of the membrane displacements via a snapshot proper orthogonal decomposition method. Digital image correlation strain measurements were used to form virtual strain sensors, which served as the sensory input to the estimation. The Poisson equation for a two-dimensional linear-elastic membrane with out-of-plane deformation was used to calculate the normal pressure distribution from virtual strain sensors using proper orthogonal decomposition basis functions and a recursive least-squares minimization. Estimated pressure distributions were compared with a high-fidelity three-dimensional computational fluid dynamic model and pressures were calculated from digital image correlation deformations. Coefficients of lift and pitching moment for steady-state flow conditions were estimated and compared with measured wind-tunnel loads. Results show promise toward the application of a low-fidelity estimation approach for real-time load-estimation applications.

Efficient hyper reduced-order model (HROM) for parametric studies of the 3D thermo-elasto-plastic calculation

This paper focuses on a 3D thermo-elasto-plastic localized thermal source simulation and its parametric analysis with high CPU efficiency in the reduced-order model (ROM) framework. The hyper reduced-order model (HROM) is introduced and improved with two choices. Firstly, three reduced bases are constructed: one for the displacement increments, one for the plastic strain increments and one for the stress state. Equilibrium equation in plasticity relies on the knowledge of plastic strain rate, hence the plastic strain has to be included into the variable to be reduced, and the incremental form is adopted in the paper. It is shown that the introduction of an extra stress basis greatly improves the quality and the efficiency of the ROM. Secondly, the reduced state variables of plastic strain increments are determined in a reduced integration domain. Concerning the parametric analysis, the interpolation of the reduced bases is based on the Grassmann manifold, which permits to generate the new proper orthogonal decomposition bases for the modified parameters. In order to increase the convergence rate, the plastic strain interpolated from snapshots (the reference cases with full FEM calculations) is considered as the initial value of each time step for the modified problem of parametric studies. As a result, the plastic calculation is always done on the confined domain and only a few iterations are then required to reach static and plastic admissibility for each time step. The parametric studies on varying thermal load and yield stress show high versatility and efficiency of the HROM coupled with Grassmann manifold interpolation. A gain of CPU time of 25 is obtained for both cases with a level of accuracy smaller than 10%.

Energy resolution with the Lorentz integral transform

A brief outline of the Lorentz Integral Transform (LIT) method is given. The method is well established and allows to treat reactions into the many-body continuum with bound-state like techniques. The energy resolution that can be achieved is studied by means of a simple two-body reaction. From the discussion it will become clear that the LIT method is an approach with a controlled resolution and that there is no principle problem to even resolve narrow resonances in the many-body continuum. As an example the isoscalar monopole resonance of 4He is considered. The importance of the choice of a proper basis for the expansion of the LIT states is pointed out. Employing such a basis a width of 180(70) keV is found for the 4He isoscalar monopole resonance when using a simple central nucleon-nucleon potential model.

A Constitutional Review of the Draft 'Macron' Law Introducing Shareholder Eviction under French Law: The Revolution that Didn't Happen

In a politically controversial attempt to modernize the French French Minister of the Economy Emmanuel Macron passed a sweeping law earlier this year, reforming many areas of French business law, including bankruptcy law. For the first time under French law shareholder eviction will be available - under certain circumstances and without any breach of the shareholder’s duties - to remove them from decisions affecting the future of a distressed company. This law is a step in the right direction to force shareholders to absorb the company’s losses and allow new shareholders to invest fresh money. Unfortunately, the French government failed to use modern, world-class economic standards to govern a shareholder eviction under the new law. First, by retaining an antiquated trigger of liquidity crisis instead of actual insolvency, the law fails to consider the enterprise value of the company (the going concern value) as the proper economic basis to recognize that shares have become worthless, an essential element to provide legitimacy for their eviction and avoid the risk of an unconstitutional violation of property rights. Second, by requiring that a judge justify the eviction by finding a necessity to avoid a risk of serious loss to the economy, the law offers a weak constitutional safeguard for property rights, a loosely defined public interest standard and little guidance for a judge to avoid arbitrary decisions and political interferences. This lack of economic and conceptual basis has unfortunately transformed a genuine attempt to reform French law into an inadequate and potentially unconstitutional new law.

Modeling Standing Waves in a Thin Layer Sonoelectrochemical System

Recent experiments in thin layer (cell height 1 cm) sonoelectrochemistry demonstrate that sonication increases the rates of electrocatalysis. Heterogeneous electron transfer rates increase substantially upon ultrasound irradiation1. A model is developed using Partial Differential Equations and the Galerkin Method (Finite Element Method) to understand catalytic effects observed when sound waves are applied in a thin layer electrochemical cell. The cell consists of a hollow Teflon cylinder with a transducer as the base seen in Figure 1. A three electrode system is used with the electrodes spaced equally apart and parallel to the cylinder base. The cylinder is filled with a redox probe and electrolyte solution such that a meniscus forms at the top. The transducer propagates sound waves through the solution (i.e., sonication). A comparison of cyclic voltammograms before, during, and after sonication reveals enhancement effects from the sound waves. For redox probes with slow kinetics, sonication simultaneously increases currents and appears to shift the reaction to more reversible. Data indicate that a combination of the height and shape of the meniscus play a vital role in this enhancement effect. Numerical analysis is used in conjunction with partial differential equations to develop the model. It takes into account the shape and height of the meniscus as well as the pressure, density, elasticity, mass, and surface tension of the fluid near the meniscus. The model then reveals the standing waves of the system. Standing waves occur in a stationary medium when waves are traveling in opposite directions and cause interference with one another. In general, if this scenario occurs with waves of approximately the same amplitude there is no net change in energy, another indication that the height of the meniscus is relevant. To help quantify this phenomenon, four equations are used. Among them are two common equations used in fluid mechanics, the Compressible Euler Equation (Equation 1), and a conservation of mass equation (Equation 2): u here represents velocity, ρ is the density, and P is the pressure. The other two equations are a boundary motion equation (Equation 3) and an equation that describes the surface tension on the meniscus (Equation 4). Ψ is a separate equation that describes the position of the surface, β is a surface tension coefficient, and H is the mean curvature of the meniscus. The Galerkin Method is used to convert our continuous problem to a discrete one via the weak formulation with a proper basis. A reduction of the wave equation to an eigenvalue problem gives way to our standing waves. The wave interference taking place in the cell can be seen below in Figure 1. This model is important for prediction of behavior of the sound waves before and after they contact the top boundary and the role of the meniscus convexity. This will lead to advances in understanding the experimental system for applications in electrocatalysis. Figure 1

Weak fault signature extraction of rotating machinery using flexible analytic wavelet transform

Extracting and revealing the weak periodic fault vibration impulses is reasonable for damage detection of rotating machinery. However, the widely used dyadic WT suffers fixed frequency partition manner and low oscillating bases which would weaken its performance in weak fault detection. A new method based on flexible analytic wavelet transform (FAWT) is proposed in this article. Employing fractional and arbitrary scaling and translation factors, FAWT possesses attractive properties such as flexible time–frequency (TF) covering manner, better shift-invariance and tunable oscillatory nature of the bases, offering proper wavelet frame and bases shape to match the weak fault components. Moreover, FAWT is effective in revealing the amplitude modulation feature of the periodic fault impulses that occur in some damaged rotating components. The applications to a rolling bearing, a planetary gearbox of, and a flue gas turbine unit show that the proposed method is effective in extracting weak impulsive fault signature.

Urban and Rural MSW Stream Characterization for Separate Collection Improvement

In the new legislation framework enacted by new member countries of the European Union (EU), the characterization of municipal solid waste (MSW) represents an important instrument for local governments and sanitation operators in setting and achieving targets for waste recycling and recovery. This paper presents the results of a study conducted in accordance with the Romanian methodology for domestic wastes characterization ROMECOM, aiming to provide a proper basis for developing clear and realistic forecasts in current municipal waste management, based on MSW composition and generation rate. The analyzed MSW came both from areas where the waste is collected in mixed and separate ways, in urban and rural areas. The MSW composition by fraction is detailed for dense urban areas, urban areas, rural and touristic areas from Romania. Based on these results, the MSW composition was determined for the eight development regions in Romania, and a generation rate of 0.9·kgMSW inhabitant−1·day−1 for the urban region and 0.4·kgMSW inh−1·day−1 for the rural region was established. The calorific values of urban and rural areas were determined as 6801 kJ·kg−1 and 5613 kJ·kg−1, respectively. In the perspective of sustainable development in this technical area, based on the obtained results and on the prognosis made for the following years, two proposals for urban and rural areas were developed for MSW treating options improvement. The two systems are characterized by selective collection (different efficiencies for urban and rural areas) with subsequent recovery of the separated materials and energy recovery of the residual waste in a large-scale waste to energy (WTE) plant.

Exploitation in Monopsony

A key feature of monopsony model is that a single firm pays its workers a wage (w) less than the marginal revenue product (MRP). This feature has been explained as a synonym of the single firm exploiting its workers since its creation by Joan Robinson [1]. By using a simple standard efficiency wage model of Yellen [2], this paper examines the conventional wisdom by showing that the firm pays workers w in the equilibrium of full employment, but paradoxically pays them w=MRP in the equilibrium of involuntary unemployment. According to the conventional wisdom that the result of w implies that workers are exploited by the firm, this finding indicates that the firm does not exploit its employees (w=MRP) when there are involuntary unemployed workers queuing for jobs, but paradoxically exploits workers (w) when there are no workers queuing for jobs. The finding is obviously counter-intuitive. This counter-intuitive finding reveals that the key feature of w in monopsony cannot be regarded as a proper theoretical basis for the issue of labor exploitation.

Congenital Virtue: Mos Maiorum in Cicero's Orations

Cicero's appeals to antiquity with the term mos maiorum, or simply maiores, in his orations enable the orator to appeal to his audience's emotions, and to highlight their collective identity and cultural heritage as the proper basis for the decision he advocates. His usage is not strongly correlated with any chronological or generic subset of the orations, as is shown by a simple statistical analysis of their distribution. It is better understood as a strategic response to the circumstances particular to each oration, in a less formal sense.

Emotional user experience: Traits, events, and states☆

Emotional experience has become an important topic in human–technology interaction research and design. Nevertheless, such research and design often lacks a proper explanatory basis and methodologically robust operationalisation. In this article, a conceptualisation of emotional user experience is formulated based on the appraisal theory of emotion, where the goal congruence of the interaction events and the task-independent individual traits are thought to underlie the user′s emotional response. A laboratory study with N=50 participants conducting ordinary computer tasks is reported. The results suggest that subjective emotional experience depends on a number of factors relating to individual differences in coping and task events. Emotional user experience, as analysed according to a competence–frustration model of emotion, is dependent on the user׳s technological problem-solving tendency, frustration tendency, pre-task self-confidence, and task performance.

G is for Genes: The Impact of Genetics on Education and Achievement.

When I received this, I pictured myself conducting a review of the technical—scientific aspects of a pedagogic manuscript that 'mentions' genetics in its contents. However, there are no words to describe my surprise while perusing the copy. 'G is for Genes' is a well-balanced interpretation of the biopsychosocial model. Its contents are well structured, consolidated, and, most of all, structured with a proper basis. When reading between the lines, you can grasp all the years of hard work the authors have conducted in their respective fields. I was delighted with their skills in presenting the structure of this topic in a persuasive fashion. 'G is for Genes' is a book that describes the importance of genotyping in the coming generations as the basis for education's individualization. This is evident by early-stage identification of the innate aptitude of the child, and by establishing standardized but flexible behaviors adapted to the individual needs to ultimately promote suitable stimuli for altering environmental factors. As a critic with a scientific/clinical view, the hard data management that sustains this new pedagogic trend proposed by the authors has left me with a good after-taste. The book clearly states and completely harmonizes the concept that health is today's world trend (at least for the viewpoint of my area of expertise): Individualization of treatment based on the kitchen recipe for each person—their genes. I want to emphasize the complete picture presented from the genetic perspective: specifically the intricate details surrounding SNP discovery, to the potential impact in and on macro economies. Even though the approach and basis of their thesis is strong and excellently structured, I sense a lack of fluency in the structured methodology required to form an educational model that can be implemented in ordinary schools. Taking into account the high cost of genotyping, it is unlikely to be embraced or used in developmental countries such as Mexico in the near future (it is prudent to note that 'Mexico' is mentioned in the book as a country that can benefit from this model). 'G is for Genes' is a futuristic and controversial book, with excellent background and painless presentation. 'Controversial', in my opinion, is the parting point for changes and improvement, and 'futuristic' is today's tomorrow. I conclude this review by stating that the book should be directed not only to teachers, pedagogues and scientists, but also to all parents, since this is an excellent tool to promote optimal development of our children based on their individual characteristics and not merely social statistics.

Atrial flutter EKG can be useless without the proper electrophysiological basis

Dear Editor:Atrial flutter is a common EKG. Still, there are factors that can inter-fere during its diagnosis, conditioning its treatment and prognostic. Agood knowledge about the basic principles of ECG can be very valuableto avoid those interferences.A 67-year-old male patient visited the emergency service due topolaquiuria andabdominal pain.There were nosignalsof cardiacsemi-ology.Bloodpressurewastakenwitharesultof234mmHgsystolicand134 mm Hg diastolic. There was neither history of hypertension,diabetes mellitus nor dyslipidemia. His medical history includedParkinson already treated with Carbidopa, Entacapona, Levodopa andbenign prostatic hyperplasia treated with Pramipexole, Domperidoneand Tamsulosin followed in urology service.A suspicious diagnosis of hypertensive crisis was given and the fol-lowingelectrocardiogramwasperformed(Fig.1).Atypicalatrialflutterelectrocardiogram with a 4:1 block was apparent. However, lead IIshows no flutter signs (Fig. 1). In fact lead II represented a completelynormal rhythm. Strikingly, a further inspection of the patient noticedthat Parkinson tremors were mostly constricted to left arm.No flutter signs at lead II plus the Parkinson tremors constricted toleft arm were thought to be related. A further study of the patientshowed that regular tremors due to Parkinson's disease on the leftarm were thought provoking the flutter-like artifact.Atrial Flutter is a common arrhythmia since its first description90 years ago. Still, there are factors that can interfereduringits diagno-sis, conditioning its treatment and prognostic.The electrocardiogram, an important and basic diagnostic proof canevenconfuseadiagnosisduetoawronginterpretation,whichmightberelated to a lack of knowledge about the ECG physiology.It has been previously reviewed the mechanisms behind equipment-related ECG artifacts [1,2]. Electrocardiographic artifacts have beenreported before in a Parkinson disease context [3] although the artifactmechanism was not explained.TheespecialfeatureofthisECGistheextendedflutter-likeartifactinall leads except II.A good knowledge about the basic principles of ECG can be veryvaluable to solve cases like this one [4].As we know, limb leads are bipolar leads. Each of them has onepositive and negative pole. Lead II is the only one that takes no infofrom the left arm electrode (LA) and its region.LA provides a mistaken intake which interfere its signal, affectingleads I and III, which use LA as one of their poles and the augmentedlimb and precordial leads (Fig. 2). Therefore, only lead II can tell us thereal heart rhythm in this case.In conclusion, ECG is a very reliable proof but it can't substitute theclinical exploration. We can't forget the clinical exploration as thebasisofthediagnosis.Diagnosticproofs,eventhosewhichareveryreli-able, are complementary to the exploration.In this case, normal ECG monitoring or recording would be possiblefor diagnostic purposes once the concomitant process is reduced ormodified.EvenitcanbepossibleusingECGtakingintoaccounttheclin-ical exploration added to the knowledge of the principles of electrocar-diography in order to contextualize the patient's condition. That willallow us to save money, time and resources in our clinical practice.References