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Closure of the appendiceal stump is a critical step during an appendectomy. There is a lack of knowledge about the feasibility of using electrosurgical devices for the occlusion of the appendix. This study aims to determine the safety of this technique in pediatric patients.We performed a cross-sectional analytical study in patients less than 18 years of age treated at Hospital Militar Central Colombia between 2012 and 2021. Our institution's ethics committee approved the study. We analyzed the data using SPSS 22 statistical program. We present frequencies for qualitative variables and measures of central tendency or dispersion for quantitative variables depending on the distribution measured by the Kolmogorov-Smirnov test. In addition, we measured the association of nominal variables with the Chi-square test or Fisher's exact test. For numerical variables, the difference of means with the Student's t-test or the difference of medians with the Mann-Whitney U test.We treated 209 patients. One hundred sixteen (55.5%) were boys, and the mean age was 9.7 years (SD 3.2). The median intraoperative time was 60 min, and the hospital stay was 2.8 days on average. There were no cases of stump leakage, and only two patients (1%) had an organ-space surgical site infection, which was unrelated to the closure technique. We found no association between procedural complications and appendicular status (p = 0.450).Our research suggests that using a bipolar sealing device (Ligasure, Medtronic, USA) for appendiceal stump closure in pediatric patients undergoing laparoscopic appendectomy is feasible and should be further studied.Treatment study.Level III.

International audience; In order to clarify the link between 40Ar/39Ar record in white mica and deformation, we performed in situ and bulkwise 40Ar/39Ar dating over the East Tenda Shear Zone (Tenda massif, alpine Corsica). White micas from 11 samples were selected and extensively analyzed using in situ techniques across nested scales of strain‐intensity gradients developed at the expense of a Late‐Variscan protolith. 40Ar/39Ar systematics are unaffected by inherited Ar and directly linked to deformation with little or no Ar lattice (volume) diffusion. Extensive sampling allows constraining the end of deformation related to burial and exhumation respectively at ~34 and ~22 Ma, bracketing the duration of regional extensional shear to ~12 Myr. Results also highlight a regional strain localization toward the upper contact of the unit with smaller‐scale localization in specific lithologies, notably meta‐aplites.Second‐order complications exist, such as local ill‐defined correlations between ages and finite‐strain microstructures. Thus, the use of a strain gradient as a proxy for strain localization in time is regionally valid but sometimes locally too complex to track or resolve strain partitioning/localization trends at the meter (outcrop) scale and below. Age mixing and incomplete isotopic homogenization by dissolution/precipitation are identified as the main causes of local discrepancies that complicate the link between age and microstructure and the derivation of strain localization rates. Tracking temporal trends in shear distribution across regional‐scale deformation gradients in such settings is possible but requires a multi‐scale approach as implemented here to reveal younging patterns associated to strain localization.

Resumen A pesar de que en las últimas décadas, el gobierno colombiano a través del Ministerio de Transporte et al., (2006), IDU (2011) e INVIAS (2013), han venido desarrollando e implementando especificaciones técnicas y metodologías orientadas al mantenimiento, reparación y rehabilitación de las vías pavimentadas a nivel nacional y distrital; se advierte que estas medidas no han sido suficientes para contrarrestar las problemáticas asociadas a los pavimentos rígidos, entre las que se encuentra el agrietamiento del concreto. Para mitigar este tipo de problemáticas, a nivel internacional se ha promovido el estudio de diferentes métodos de autorreparación a través de la adición de cepas bacterianas, que favorezcan la precipitación de cristales de carbonato de calcio (CaCO3) como una posible alternativa para el relleno y sellado de fisuras en el concreto. En este trabajo se plantean dos objetivos esenciales: primero, realizar una aproximación al estado del arte sobre diferentes métodos que pueden permitir la “Autorreparación de fisuras en concreto rígido para pavimentos mediante la adición de bacterias bioprecipitadoras de carbonato de calcio”, como una posible alternativa para la reparación, mantenimiento y durabilidad de las estructuras de pavimento en concreto. En segundo lugar, se busca formular un diseño experimental que sirva como marco de referencia para realizar investigaciones sobre métodos biológicos de autorreparación de concreto en la Universidad Nacional de Colombia, factibles de aplicarse en nuestro medio. Para ello, inicialmente se realizó una revisión teórica y conceptual sobre los principales aspectos que intervienen en el proceso de autorreparación de fisuras en concreto mediante la adición de bacterias bioprecipitadoras de carbonato de calcio (CaCO3). Igualmente, se realizó una recopilación bibliográfica sobre diferentes artículos científicos que evalúan la efectividad de diferentes bacterias bioprecipitadoras de carbonato de calcio (CaCO3) en la autorreparación de fisuras, mediante pruebas de resistencia a la compresión, flexión y tracción, permeabilidad y absorción de agua. Con base en las experiencias previas, se planteó una propuesta de diseño experimental que incluyó: la selección de materiales y cepas bacterianas; diseño de mezcla, preparación de muestras con y sin adición de bacterias; realización de pruebas físicas, mecánicas y microscópicas, que permitan evaluar la eficiencia del método de autorreparación estudiado y aproximación de los costos para un eventual desarrollo de la propuesta “Diseño experimental sobre métodos biológicos de autorreparación del concreto”. Abstract. Over the last few decades, the Colombian government, through the ministry of transport et al, (2006), IDU (2011) e INVIAS (2013), have developed and implemented specific techniques and methodologies used for the repairing and upgrading of paved roads, both on national and district roads. It is noted that these measures have not been enough to counteract the problems associated with rigid pavements, including concrete cracking. To mitigate this type of problem, the study of different self-healing methods has been promoted internationally through the addition of bacterial strains, favoring the precipitation of calcium carbonate crystals (CaCO3) as a possible alternative for the filling and sealing cracks in concrete. In this study two essential objectives are propose: firstly, to make an approximation to the state of the art on different methods that will allow the "Self-healing of cracks in concrete on rigid pavement through the addition of bio-precipitating calcium carbonate bacteria", as a possible alternative for the repair, maintenance and durability of concrete pavement structures. Secondly, it is intended to formulate an experimental design that serves as a support point for research on biological methods of self-healing concrete at the National University of Colombia, feasible to be applied in our environment. For this, initially a theoretical and conceptual review was carried out on the principals aspects involved in the process of self-healing of cracks in concrete through the addition of bioprecipitating calcium carbonate (CaCO3) bacteria. Also, a bibliographical compilation was carried out on different scientific articles that evaluate the effectiveness of different bioprecipitating calcium carbonate (CaCO3) bacteria, in the self - healing of cracks, through tests of strength compression, flexure and traction, permeability and water absorption. Based on the previous experiences, a proposal of experimental design was proposed that includes the selection of materials and bacterial strains, the design of mixture, preparation of samples with and without addition of bacteria and physical, mechanical and microscopic tests that allow to evaluate the efficiency of the self-healing method studied. Maestría

This paper reports the results of two experimental campaigns aimed at studying the high-frequency response of a raceway containing low voltage power, telephone, and Ethernet cables, to external electromagnetic field illumination. The raceway was tested against HPEM transients inside a GTEM cell and low power fields inside a reverberation chamber (RC). The HPEM tests revealed that the low voltage power cables have the greatest coupling under a hyperband illumination, compared to telephone and Ethernet cables. The RC tests allowed the determination of statistical transfer functions from random incident field configurations into DM voltage in cable loads. The responses were found to be governed by the raceway under test at the lower frequencies (below 1 GHz). Between 0.2-1 GHz, the raceway gives about 10 dB higher coupling than a short patch cable. The difference is even greater at lower frequencies and for shielded cables. In the frequency band 1-3 GHz, little difference was observed between short patch cables and the full raceway, but both were still significantly higher than direct coupling to the measurement card. Beyond 3 GHz, the coupling is clearly dominated by the terminal equipment. The experiments performed in this work provide a better understanding of the expected induced voltages and currents in commercial cable systems when exposed to IEMI-like signals.

International audience; De nombreuses études se sont intéressées à l'analyse et la détection d'attaques électromagnétiques à l'encontre de systèmes électroniques critiques au niveau sous-système ou composant. Les effets induits par de telles attaques sont classifiés uniquement selon l'état de fonctionnement des équipements suite à une agression. L'étude des symptômes préliminaires de ces effets n'a, à notre connaissance, jamais été considérée. Dans ce travail, nous proposons d'instrumenter un ensemble de capteurs internes qui peuvent être utilisés pour la pré-détection d'attaques électromagnétiques.