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INTRODUCTION: Gender equity in urological meetings is pivotal for fostering diversity and inclusivity in the field. This study aims to evaluate the representation of Spanish urologist and regional disparities, and to assess its alignment with the demographic composition of the urological community. MATERIALS AND METHODS: All urology meetings organized by the AEU between January 2012 and December 2022 were reviewed, including meeting information and details of the faculty. Additionally, we analysed geographic distribution of speakers across 17 different regions. Gender demographics were obtained disaggregating data by sex and year from the Organización Médica Colegial de España (OMC) and from those urologists affiliated to the AEU. RESULTS: Analysing 52 AEU congresses held from 2012 to 2022, encompassing 3,407 speakers, the study found that 95.25% of speakers were from Spain and 89.6% were male speakers. Over the years, there was a positive trend in female speaker representation, increasing by 1.1% annually, slightly lagging the 1.8% annual rise in the number of female urologists in Spain. In specific subfields like functional, transplantation, and oncology sessions, the study revealed a higher representation of women, indicating focused efforts in these areas. Geographically, Madrid, Catalonia and Andalusia exhibited the highest representation. CONCLUSIONS: Although there was a positive trend towards an increased participation of female urologists in Spanish urological meetings, it fails to accurately reflect the proportional increase in the number of women entering the urology profession in recent years. This study underscores the importance of ongoing efforts to ensure diverse and balanced representation in urological forum.

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PURPOSE: To report oncologic outcomes of patients undergoing salvage cryotherapy (SCT) for local recurrence of prostate cancer (PCa) and to establish a nadir PSA (nPSA) value that best defines long-term oncologic success. METHODS: Retrospective study of men who underwent SCT for local recurrence of PCa between 2008 and 2020. SCT was performed in men with biochemical recurrence (BCR), after primary treatment and with biopsy-proven PCa local recurrence. Survival analysis with Kaplan-Meier and Cox models was performed. We determined the optimal cutoff nPSA value after SCT that best classifies patients depending on prognosis. RESULTS: Seventy-seven men who underwent SCT were included. Survival analysis showed a 5-year biochemical recurrence-free survival (BRFS), androgen deprivation therapy-free survival (AFS), and metastasis-free survival (MFS) after SCT of 48.4%, 62% and 81.3% respectively. On multivariable analysis for perioperative variables associated with BCR, initial ISUP, pre-SCT PSA, pre-SCT prostate volume and post-SCT nPSA emerged as variables associated with BCR. The cutoff analysis revealed an nPSA < 0.5 ng/ml to be the optimal threshold that best defines success after SCT. 5-year BRFS for patients achieving an nPSA < 0.5 vs nPSA ≥ 0.5 was 64% and 9.5% respectively (p < 0.001). 5-year AFS for men with nPSA < 0.5 vs ≥ 0.5 was 81.2% and 12.2% (p < 0.001). Improved 5-year MFS for patients who achieved nPSA < 0.5 was also obtained (89.6% vs 60%, p = 0.003). CONCLUSION: SCT is a feasible rescue alternative for the local recurrence of PCa. Achieving an nPSA < 0.5 ng/ml after SCT is associated with higher long-term BRFS, AFS and MFS rates.

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During the consumption of alkanes, Alcanivorax borkumensis will form a biofilm around an oil droplet, but the role this plays during degradation remains unclear. We identified a shift in biofilm morphology that depends on adaptation to oil consumption: Longer exposure leads to the appearance of dendritic biofilms optimized for oil consumption effected through tubulation of the interface. In situ microfluidic tracking enabled us to correlate tubulation to localized defects in the interfacial cell ordering. We demonstrate control over droplet deformation by using confinement to position defects, inducing dimpling in the droplets. We developed a model that elucidates biofilm morphology, linking tubulation to decreased interfacial tension and increased cell hydrophobicity.

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In embryonic development or tumor evolution, cells often migrate collectively within confining tracks defined by their microenvironment 1,2. In some of these situations, the displacements within a cell strand are antiparallel 3, giving rise to shear flows. However, the mechanisms underlying these spontaneous flows remain poorly understood. Here, we show that an ensemble of spindle-shaped cells plated in a well-defined stripe spontaneously develop a shear flow whose characteristics depend on the width of the stripe. On wide stripes, the cells self-organize in a nematic phase with a director at a well-defined angle with the stripe's direction, and develop a shear flow close to the stripe's edges. However, on stripes narrower than a critical width, the cells perfectly align with the stripe's direction and the net flow vanishes. A hydrodynamic active gel theory provides an understanding of these observations and identifies the transition between the non-flowing phase oriented along the stripe and the tilted phase exhibiting shear flow as a Fréedericksz transition driven by the activity of the cells. This physical theory is grounded in the active nature of the cells and based on symmetries and conservation laws, providing a generic mechanism to interpret in vivo antiparallel cell displacements.

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We investigate the large length and long time scales collective flows and structural rearrangements within in vitro human bronchial epithelial cell (HBEC) cultures. Activity-driven collective flows result in ensembles of vortices randomly positioned in space. By analyzing a large population of vortices, we show that their area follows an exponential law with a constant mean value and their rotational frequency is size independent, both being characteristic features of the chaotic dynamics of active nematic suspensions. Indeed, we find that HBECs self-organize in nematic domains of several cell lengths. Nematic defects are found at the interface between domains with a total number that remains constant due to the dynamical balance of nucleation and annihilation events. The mean velocity fields in the vicinity of defects are well described by a hydrodynamic theory of extensile active nematics.

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We present a hydrodynamic model of spreading epithelial monolayers described as polar viscous fluids, with active contractility and traction on a substrate. The combination of both active forces generates an instability that leads to nonlinear traveling waves, which propagate in the direction of polarity with characteristic time scales that depend on contact forces. Our viscous fluid model provides a comprehensive understanding of a variety of observations on the slow dynamics of epithelial monolayers, remarkably those that seemed to be characteristic of elastic media. The model also makes simple predictions to test the non-elastic nature of the mechanical waves, and provides new insights into collective cell dynamics, explaining plithotaxis as a result of strong flow-polarity coupling, and quantifying the non-locality of force transmission. In addition, we study the nonlinear regime of waves deriving an exact map of the model into the complex Ginzburg-Landau equation, which provides a complete classification of possible nonlinear scenarios. In particular, we predict the transition to different forms of weak turbulence, which in turn could explain the chaotic dynamics often observed in epithelia.

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Collective cell migration in spreading epithelia in controlled environments has become a landmark in our current understanding of fundamental biophysical processes in development, regeneration, wound healing or cancer. Epithelial monolayers are treated as thin layers of a viscous fluid that exert active traction forces on the substrate. The model is exactly solvable and shows a broad range of applicabilities for the quantitative analysis and interpretation of force microscopy data of monolayers from a variety of experiments and cell lines. In addition, the proposed model provides physical insights into how the biological regulation of the tissue is encoded in a reduced set of time-dependent physical parameters. In particular the temporal evolution of the effective viscosity entails a mechanosensitive regulation of adhesion. Besides, the observation of an effective elastic tensile modulus can be interpreted as an emergent phenomenon in an active fluid.

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AIM: Immunosuppression is believed to worsen outcomes for patients who require surgery for perforated diverticulitis. The aim of this study was to compare surgical outcomes between immunocompromised and immunocompetent patients undergoing surgery for complicated diverticulitis. METHOD: All patients who underwent emergency surgery for complicated diverticulitis between 2004 and 2012 in a single unit were studied. Patients were classified as immunosuppressed (group I) or immunocompetent (group II). Operation type and postoperative morbidity and mortality were compared between groups. The impact of operating surgeons' specialization and the Peritonitis Severity Score (PSS) were also evaluated to determine their impact on the restoration of gastrointestinal (GI) continuity. RESULTS: One-hundred and sixteen patients (mean age: 63.7 years), 41.4% women, were included. Fifty-three (45.7%) patients were immunosuppressed (group I): 42 underwent Hartmann's procedure (HP) (79.2%), nine (17.0%) underwent resection and primary anastomosis (RPA) with ileostomy (IL) and two (3.8%) underwent RPA without IL. In group II, 15 HP (23.8%), nine RPA with IL (14.3%) and 39 RPA without IL (61.9%) were performed. Postoperative morbidity and mortality were 79.2% and 26.4%, respectively, in group I and 63.5% and 6.3%, respectively, in group II. The overall mean PSS was 9.5, with a mean PSS of 11.1 in group I and of 8.1 in group II. The decision to perform a primary anastomosis differed significantly between colorectal surgeons and general surgeons in the patients with a PSS of 9-10-11. CONCLUSION: In immunocompromised patients, RPA with IL can be a safe surgical option, whereas HP should be reserved for patients with a PSS of > 11. Colorectal surgical specialization is associated with higher rates of restoration of GI continuity in patients with perforated diverticulitis, especially in patients with an intermediate PSS score. Evaluation of each patient's PSS facilitates decision making in surgery for perforated diverticulitis.

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We study and classify the time-dependent morphologies of polarized tissues subject to anisotropic but spatially homogeneous growth. Extending previous studies, we model the tissue as a fluid, and discuss the interplay of the active stresses generated by the anisotropic cell division and three types of passive mechanical forces: viscous stresses, friction with the environment and tension at the tissue boundary. The morphology dynamics is formulated as a free-boundary problem, and conformal mapping techniques are used to solve the evolution numerically. We combine analytical and numerical results to elucidate how the different passive forces compete with the active stresses to shape the tissue in different temporal regimes and derive the corresponding scaling laws. We show that in general the aspect ratio of elongated tissues is non-monotonic in time, eventually recovering isotropic shapes in the presence of friction forces, which are asymptotically dominant.

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We show that actin lamellar fragments driven solely by polymerization forces at the bounding membrane are generically motile when the circular symmetry is spontaneously broken, with no need of molecular motors or global polarization. We base our study on a nonlinear analysis of a recently introduced minimal model [Callan-Jones et al., Phys. Rev. Lett. 100, 258106 (2008)]. We prove the nonlinear instability of the center of mass and find an exact and simple relation between shape and center-of-mass velocity. A complex subcritical bifurcation scenario into traveling solutions is unfolded, where finite velocities appear through a nonadiabatic mechanism. Examples of traveling solutions and their stability are studied numerically.

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Many synthetic or natural fibers are produced via the transformation of a liquid solution into a solid filament, which allows the wet processing of high molecular weight polymers, proteins, or inorganic particles. Synthetic wet-spun fibers are used in our everyday life from clothing to composite reinforcement applications. Spun fibers are also common in nature. Silk solidification results from the coagulation of protein solutions. The chemical phenomena involved in the formation of all these classes of fibers can be quite different but they all share the same fundamental transformation from a liquid to a solid state. The solidification process is critical because it governs the production rate and the strength that fibers can sustain to be drawn and wound. An approach is proposed in this work to investigate the kinetics of fiber solidification. This approach consists in circulating solidifying fibers in the extensional flow of a surrounding liquid. Such as polymers in extensional flows, the fibers break if resultant drag forces exceed the fiber tensile strength. The solidification kinetics of nanotube composite fibers serves as a validation example of this approach. The method could be extended to other systems and advance thereby the science and technology of fiber and textile materials. It is also a way to directly visualize the scission of chain-like systems in extensional flows.

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El objetivo de este reporte es describir las acciones que se realizan en la promoción del consumo de frutas y hortalizas. En Cuba, las enfermedades del corazón, cerebrovasculares y los tumores malignos representan las tres primeras causas de muerte. El sobrepeso y la obesidad se incrementan progresivamente. La II Encuesta de Factores de Riesgo a Enfermedades no Transmisibles realizada en el 2002 en una muestra representativa de la población cubana mayor de 15 años de edad, mostró un patrón alimentario inadecuado en una alta proporción de la población, principalmente por un bajo consumo de frutas y hortalizas. El Programa de Educación Nutricional coordinado por el Instituto de Nutrición e Higiene de los Alimentos y el Centro de Promoción y Educación para la Salud contribuyen a fortalecer un Plan de Acción entre otros factores para cumplir las metas trazadas en el Plan Nacional de Acción para la Nutrición, promoviendo cambios favorables en los patrones dietéticos con una activa participación de la población.

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