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La motivación en el trabajo ha sido a la larga de la historia empresarial objeto de estudio, dado que ella le aporta los estímulos requeridos a una persona para que se conecte con el puesto y la organización. El plan motivacional de una organización debe responder a las necesidades reales de las personas que la conforman, por ello se conceptualiza y se identifican las ventajas de la teoría de las Ocho Anclas aplicables en la organización.

[EN] These are the advantages of technology: multimedia presentation, interaction, personalization, etc. Within this context an interactive digital book of the characteristics of the information was realized. In a data set, the following characteristics are usually of paramount importance: 1. the center, 2. the variation, 3. the distribution, 4. the atypical values and 5. The characteristics of the data that change over time. It is important to understand the standard deviation values using tools such as the general rule of rank. Because technology allows us to get many of these statistics automatically, it is not so important to memorize formulas or perform complex arithmetic calculations by hand on the other hand, so that the students can concentrate on understanding and interpreting the values that are obtained from them.The interactive digital book of measures of central tendency contemplates that each chapter indicates prerequisites, learning objectives, written development of the subject, videos with explanation, interactive exercises, widget (html 5. Interactive galleries, interactive images, etc.) review questions.The interactive digital book will provide students with full-screen experience with galleries, videos, interactive diagrams, 3D objects, and math expressions and more; these books give life to the content in ways that a printed page can not do. Students will no longer be limited to static images that illustrate traditional texts, but can now immerse themselves in an image with interactive subtitles, rotate a 3D object or make an answer come to life in a chapter review. You can flip through a book with a single finger on the screen. They can also highlight text, take notes, look up content and find definitions in a glossary very easily. In addition, they can take them wherever they go, which will allow students not only to learn between the walls of the classroom, but also in the virtual space that make up these books., To the PAPIME 104420, project for the support provided in carrying out this work

Modelling of small-scale heterogeneous catalytic systems with master equations captures the impact of molecular noise, but can be computationally expensive. On the other hand, the chemical Fokker–Planck approximation offers an excellent alternative from an efficiency perspective. The Langevin equation can generate stochastic realisations of the Fokker–Planck equation; yet, these realisations may violate the conditions 0 ≤ θ ≤ 1 (where θ is surface coverage). In this work, we adopt Skorokhod’s formulations to impose reflective boundaries that remedy this issue. We demonstrate the approach on a simple system involving a single species and describing adsorption, desorption, reaction and diffusion processes on a lattice. We compare different numerical schemes for the solution of the resulting reflected Langevin equation and calculate rates of convergence. Our benchmarks should guide the choice of appropriate numerical methods for the accurate and efficient simulation of chemical systems in the catalysis field.

Background A successful penile prosthesis implantation (PPI) surgery can be defined by outcomes beyond the absence of complications. Aim To introduce the concept of failure to cure (FTC) in the context of PPI to more accurately gauge postoperative outcomes after PPI. Methods Consecutive patients from our sexual function registry who underwent PPI from January 2011 to December 2013 were analyzed. Demographics, previous treatment of erectile dysfunction, comorbidities, social history, postoperative problems (POPs), and surgical outcomes were tabulated. Patients completed the International Index of Erection Function (IIEF) and the Erectile Dysfunction Inventory of Treatment Satisfaction questionnaires. We defined a complication, according to the Clavien-Dindo classification, as any deviation from the ideal postoperative course that is not inherent in the procedure and does not constitute an FTC. FTC was defined as a POP that was not a complication. The χ2 tests, t-tests, or Wilcoxon rank-sum tests were used. Outcomes Patient-reported and objective outcomes after PPI. Results Our enrollment consisted of 185 patients, and we contacted 124 (67%). Of these, 16 (12.9%) had a POP requiring reoperation. Eight patients developed surgical complications (three infections, four erosions, and one chronic pain). Eight patients had FTC (four malpositions and four malfunctions). Factors that correlated with POPs were previous PPI, body mass index higher than 30 kg/m2, and previous treatment with intracorporal injections (P < .05 for all comparisons). Patients who had POPs scored significantly lower on the IIEF erectile function and intercourse satisfaction domains (P < .05 for the two comparisons), but not on the orgasmic function, sexual desire, and overall satisfaction domains (P > .05 for all comparisons). Clinical Implications POPs after PPI surgery can be more accurately categorized using the Clavien-Dindo classification of surgical complications to more clearly distinguish surgical complications from FTC. Strengths and Limitations Limitations of our study include its retrospective approach. Our series included a large proportion of patients treated for prostate cancer, which limits the generalizability of our findings. We also had a relatively short median follow-up time of 27 months. Conclusions Patient-reported outcome assessments can vary greatly from what physicians determine to be successful PPI. An assessment of POPs encompasses more than just complication rates; it also reflects FTC. Even when POPs occur, patients can still derive satisfaction if they are correctively managed. Factors that possibly predispose to POPs include previous PPI surgery, body mass index greater than 30 kg/m2, and history of intracorporal injections.

Introduction Penile prosthesis infections remain challenging despite advancements in surgical technique, device improvements, and adoption of antibiotic prophylaxis guidelines. Aim To investigate penile prosthesis infection microbiology to consider which changes in practice could decrease infection rates, to evaluate current antibiotic prophylaxis guidelines, and to develop a proposed algorithm for penile prosthesis infections. Methods This retrospective institutional review board–exempt multi-institutional study from 25 centers reviewed intraoperative cultures obtained at explantation or Mulcahy salvage of infected three-piece inflatable penile prostheses (IPPs). Antibiotic usage was recorded at implantation, admission for infection, and explantation or salvage surgery. Cultures were obtained from purulent material in the implant space and from the biofilm on the device. Main Outcome Measures Intraoperative culture data from infected IPPs. Results Two hundred twenty-seven intraoperative cultures (2002–2016) were obtained at salvage or explantation. No culture growth occurred in 33% of cases and gram-positive and gram-negative organisms were found in 73% and 39% of positive cultures, respectively. Candida species (11.1%), anaerobes (10.5%) and methicillin-resistant Staphylococcus aureus (9.2%) constituted nearly one third of 153 positive cultures. Multi-organism infections occurred in 25% of positive cultures. Antibiotic regimens at initial implantation were generally consistent with American Urological Association (AUA) and European Association of Urology (EAU) guidelines. However, the micro-organisms identified in this study were covered by these guidelines in only 62% to 86% of cases. Antibiotic selection at admissions for infection and salvage or explantation varied widely compared with those at IPP implantation. Conclusion This study documents a high incidence of anaerobic, Candida, and methicillin-resistant S aureus infections. In addition, approximately one third of infected penile prosthesis cases had negative cultures. Micro-organisms identified in this study were not covered by the AUA and EAU antibiotic guidelines in at least 14% to 38% of cases. These findings suggest broadening antibiotic prophylaxis guidelines and creating a management algorithm for IPP infections might lower infection rates and improve salvage success.

In this paper, systematic studies are performed to identify the parameters that influence the selective separation of actinides from a mixture with lanthanides in small channels. In particular, the separation of dioxouranium metal ions (UO2+2) from a binary U(VI)/Er(III) mixture in a nitric acid solution by an organic TBP/kerosene (Exxsol D80) phase, relevant to spent nuclear fuel reprocessing is investigated. The effects of parameters such as TBP concentration, organic-to-aqueous phase flow rate ratio, channel size, and residence time on mass transfer are evaluated, whilst the mass transfer performance in the extraction channels is further analysed using two important hydrodynamic features, i.e. plug formation time and interfacial area to volume ratio. Circular channels with diameters from 1 to 3 mm are used to investigate the effect of scale on the mass transfer characteristics. The importance of the mixing zone on mass transfer is also evaluated. A CFD model is proposed to simulate the mass transfer during plug flow. Using only one experimental point, once the plug has been formed, the model is able to predict extraction percentage with less than 4% difference compared to the experiments.

In this work, the extraction of U(VI) by tributyl phosphate (TBP) is studied in small channels of different sizes, operated in segmented flow. The variables analysed include the channel diameter (1–4 mm I.D.), mixture velocity (1.06 - 4.24 cm s−1), volume fraction of the continuous phase (between 0.200 and 0.500), and concentration of extractant (TBP 30% v/v in kerosene and TBP 100%). The hydrodynamic characteristics of the flow, such as plug and slug lengths, specific interfacial area, and dispersed phase holdup, were obtained experimentally using high-speed imaging, while the pressure drop was measured with a differential pressure transducer. These parameters were correlated to the studied variables. The concentration of uranium in the aqueous phase was measured with UV-vis spectroscopy, and the mass transfer coefficients were compared with the predictions of a numerical model of segmented flow developed in Comsol Multiphysics, with good agreement.

Modeling the kinetics of surface catalyzed reactions is essential for the design of reactors and chemical processes. The majority of microkinetic models employ mean-field approximations, which lead to an approximate description of catalytic kinetics by assuming spatially uncorrelated adsorbates. On the other hand, kinetic Monte Carlo (KMC) methods provide a discrete-space continuous-time stochastic formulation that enables an accurate treatment of spatial correlations in the adlayer, but at a significant computation cost. In this work, we use the so-called cluster mean-field approach to develop higher order approximations that systematically increase the accuracy of kinetic models by treating spatial correlations at a progressively higher level of detail. We further demonstrate our approach on a reduced model for NO oxidation incorporating first nearest-neighbor lateral interactions and construct a sequence of approximations of increasingly higher accuracy, which we compare with KMC and mean-field. The latter is found to perform rather poorly, overestimating the turnover frequency by several orders of magnitude for this system. On the other hand, our approximations, while more computationally intense than the traditional mean-field treatment, still achieve tremendous computational savings compared to KMC simulations, thereby opening the way for employing them in multiscale modeling frameworks.

Understanding the mechanisms that control tissue morphogenesis and homeostasis is a central goal not only in developmental biology but also has great relevance for our understanding of various diseases, including cancer. A model organism that is widely used to study the control of tissue morphogenesis and proportioning is the Dictyostelium discoideum. While there are mathematical models describing the role of chemotactic cell motility in the Dictyostelium assembly and morphogenesis of multicellular tissues, as well as models addressing possible mechanisms of proportion regulation, there are no models incorporating both these key aspects of development. In this paper, we introduce a 1D hyperbolic model to investigate the role of two morphogens, DIF and cAMP, on cell movement, cell sorting, cell-type differentiation and proportioning in Dictysotelium discoideum. First, we use the non-spatial version of the model to study cell-type transdifferentiation. We perform a steady-state analysis of it and show that, depending on the shape of the differentiation rate functions, multiple steady-state solutions may occur. Then we incorporate spatial dynamics into the model, and investigate the transdifferentiation and spatial positioning of cells inside the newly formed structures, following the removal of prestalk or prespore regions of a Dictyostelium slug. We show that in isolated prespore fragments, a tipped mound-like aggregate can be formed after a transdifferentiation from prespore to prestalk cells and following the sorting of prestalk cells to the centre of the aggregate. For isolated prestalk fragments, we show the formation of a slug-like structure containing the usual anterior–posterior pattern of prestalk and prespore cells.

We theoretically study the impact of an external noise on a kinetic mean-field model for the bistable catalytic CO oxidation on Pd(111) surfaces. A spatially homogeneous Gaussian white noise is imposed on the fraction of CO in the constant gas flow directed at the surface and the resulting stochastic system is analyzed by a set of Langevin equations. Using an adiabatic elimination technique, we are able to analyze the interplay between the noise and the kinetic bistability reported for this surface reaction in recent experimental studies. The analytical results predict a strong impact on the bistability phase diagram. The stochastic effects are analyzed by computing stationary solutions of the probability distribution functions and the transition times between the active and inactive states of the bistable region. We also introduce an effective potential description that allows us to analyze the impact of noise. © 2014-IOS Press.

15 pages, 7 figures., We study the effects of diffusing opinions on the Deffuant et al. model for continuous opinion dynamics. Individuals are given the opportunity to change their opinion, with a given probability, to a randomly selected opinion inside an interval centered around the present opinion. We show that diffusion induces an order-disorder transition. In the disordered state the opinion distribution tends to be uniform, while for the ordered state a set of well defined opinion clusters are formed, although with some opinion spread inside them. If the diffusion jumps are not large, clusters coalesce, so that weak diffusion favors opinion consensus. A master equation for the process described above is presented. We find that the master equation and the Monte-Carlo simulations do not always agree due to finite-size induced fluctuations. Using a linear stability analysis we can derive approximate conditions for the transition between opinion clusters and the disordered state. The linear stability analysis is compared with Monte Carlo simulations. Novel interesting phenomena are analyzed., We acknowledge the financial support of project FIS2007- 60327 from MICINN (Spain) and FEDER (EU) and project FP6-2005-NEST-Path-043268 (EU). M. P. is supported by the Belgian Federal Government (IAP project "NOSY: Nonlinear systems, stochastic processes and statistical mechanics").

We study the Deffuant et al model for continuous-opinion dynamics under the influence of noise. In the original version of this model, individuals meet in random pairwise encounters after which they compromise or not depending on a confidence parameter. Free will is introduced in the form of noisy perturbations: individuals are given the opportunity to change their opinion, with a given probability, to a randomly selected opinion inside the whole opinion space. We derive the master equation of this process. One of the main effects of noise is to induce an order–disorder transition. In the disordered state the opinion distribution tends to be uniform, while for the ordered state a set of well defined opinion clusters are formed, although with some opinion spread inside them. Using a linear stability analysis we can derive approximate conditions for the transition between opinion clusters and the disordered state. The master equation analysis is compared with direct Monte Carlo simulations. We find that the master equation and the Monte Carlo simulations do not always agree due to finite-size-induced fluctuations that we analyze in some detail.

7 pages, 6 figures.-- PACS 81.65.Mq, 82.65.+r, 82.20.-w, 82.30.-b, The influence of external noise on minimalistic models for the catalytic CO oxidation on Ir(111) and Pt(111) is studied by means of the adiabatic elimination technique. Two models, which reproduce the bistable behavior usually observed in CO oxidation on Pt group metal surfaces, are analyzed. The noise is superposed on the fraction of CO in the constant gas flow directed at the surfaces and the resulting stochastic systems are reduced after the adiabatic elimination of oxygen coverage. This reduction allows us to analyze theoretically the interplay between external noise and the kinetic bistability of CO oxidation. We report the phenomena of noise-induced shifts of steady states and noise-induced jumps between stable steady states. We also present evidence for noise-induced transitions from mono- to bistability. The theoretical results are compared with simulations of the original two-variable stochastic reaction systems., We acknowledge the financial support of Project No. FIS2007-60327 from MICINN (Spain) and FEDER (EU)

We have previously shown that the surface alphabeta T cell antigen receptor (TCR).CD3 complex borne by human CD4(+) and CD8(+) T lymphocytes can be distinguished using mAbs. Using two unrelated sets of antibodies, we have now extended this finding to the surface alphabetaTCR.CD3 of seven additional mammalian species (six non-human primates and the mouse). We have also produced data supporting that differential glycosylation of the two main T cell subsets is involved in the observed TCR.CD3 antibody-binding differences in humans. First, we show differential lectin binding to human CD4(+) versus CD8(+) T lymphocytes, particularly with galectin 7. Second, we show that certain lectins can compete differentially with CD3 mAb binding to human primary CD4(+) and CD8(+) T lymphocytes. Third, N-glycan disruption using swainsonine was shown to increase mAb binding to the alphabetaTCR.CD3. We conclude that the differential antibody binding to the surface alphabetaTCR.CD3 complex of primary CD4(+) and CD8(+) T lymphocytes is phylogenetically conserved and associated with differential glycosylation. The differences may be exploited for therapeutic purposes, such as T cell lineage-specific immunosuppression of graft rejection. Also, the impact of glycosylation on CD3 antibody binding requires a cautious interpretation of CD3 expression levels and T cell numbers in clinical diagnosis.

The phenomena of synchronization and nontrivial collective behavior are studied in a model of coupled chaotic maps with random global coupling. The mean field of the system is coupled to a fraction of elements randomly chosen at any given time. It is shown that the reinjection of the mean field to a fraction of randomly selected elements can induce synchronization and nontrivial collective behavior in the system. The regions where these collective states emerge on the space of parameters of the system are calculated., Comment: 2 pages, 2 figs, accepted in The European Physical Journal

The phenomenon of synchronization occurring in a locally coupled map lattice subject to an external drive is compared to the synchronization process in an autonomous coupled map system with similar local couplings plus a global interaction. It is shown that chaotic synchronized states in both systems are equivalent, but the collective states arising after the chaotic synchronized state becomes unstable can be different in these two systems. It is found that the external drive induces chaotic synchronization as well as synchronization of unstable periodic orbits of the local dynamics in the driven lattice. On the other hand, the addition of a global interaction in the autonomous system allows for chaotic synchronization that is not possible in a large coupled map system possessing only local couplings., 4 pages, 3 figs, accepted in Phys. Rev. E

5 pages, 6 figures., This letter focus on the effect of repulsive interactions on the adoption of an external message in an opinion model. With a simple change in the rules, we modify the Deffuant \emph{et al.} model to incorporate the presence of repulsive interactions. We will show that information receptiveness is optimal for an intermediate fraction of repulsive links. Using the master equation as well as Monte Carlo simulations of the message-free model, we identify the point where the system becomes optimally permeable to external influence with an order-disorder transition., We acknowledge financial support by the MEC (Spain) and FEDER (EU) through project FIS2007-60327. TVM acknowledges the support of FCT (Portugal) through Grant No. SFRH/BD/23709/2005, MP is supported by the Belgian Federal Government (IAP project ”NOSY: Nonlinear systems, stochastic processes and statistical mechanics”).