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We investigate the formation and maintenance of the homeostatic state in the case of 2D epithelial tissues following an induction of hyperosmotic conditions, using media enriched with 80 to 320 mOsm of mannitol, NaCl, and urea. We characterise the changes in the tissue immediately after the osmotic shock, and follow it until the new homeostatic state is formed. We characterise changes in cooperative motility and proliferation pressure in the tissue upon treatment with the help of a theoretical model based on the delayed Fisher-Kolmogorov formalism, where the delay in density evolution is induced by the the finite time of the cell division. Finally we explore the adaptation of the homeostatic tissue to highly elevated osmotic conditions by evaluating the morphology and topology of cells after 20 days in incubation. We find that hyperosmotic environments together with changes in the extracellular matrix induce different mechanical states in viable tissues, where only some remain functional. The perspective is a relation between tissue topology and function, which could be explored beyond the scope of this manuscript. Experimental investigation of morphological effect of change of osmotic conditions on long-term tissue morphology and topology Effect of osmotic changes on transient tissue growth behaviour Analysis of recovery process of tissues post-osmotic-shock Toxicity limits of osmolytes in mid- to long-term tissue evolution Tissue adaptation to physiological changes in environment Long-term tissue stabilisation under altered osmotic conditions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Background: Isolated exclusion of the non-coronary sinus (NCS) is an attractive strategy in valve-sparing aortic root surgery, which avoids the mobilisation and re-implantation of coronary ostia. However, the long-term durability of aortic valve repair and the fate of remnant sinuses of Valsalva remain unclear., Method: From January 2006 to December 2013, 29 patients underwent replacement of the ascending aorta extending to the NCS (group NCS) and 56 patients underwent a modified Yacoub procedure (group MY) in our centre by a single surgeon. Significant difference of preoperative parameters was observed between two groups in the presence of bicuspid aortic valve (41.4% vs 12.5%, p=0.002) and the diameter of the sinus of Valsalva (47.3±4.7 mm vs 51.5±4.9 mm, p=0.01)., Results: The group NCS, as compared to the group MY, was associated with significantly shorter cardiopulmonary bypass time (106.6±40.5 min vs 138.4±37.5 min, p=0.001) and aortic cross clamping time (69.0±21.8 min vs 105.4±27.8 min, p<0.01). The mean follow-up was 11.5±2.8 years. No surgical re-intervention was performed for aortopathies of the aortic root; the neo-sinus were not dilated in either groups (38.2±4.2 mm vs 34.0±4.0 mm, p<0.01). The 10-year freedom from aortic valve-related re-operation was estimated to be 96.6±3.4% and 94.5±3.1% (p=0.58), and the cumulative 10-year survival rates were 95.2±4.6% and 85.6±4.7% (p=0.61) in the group NCS and the group MY, respectively., Conclusions: Aortic valve-sparing isolated NCS replacement can be safely performed in selected patients; its early outcomes, overall survival and long-term freedom from aortic valve-related or aortopathy-related re-intervention were comparable to those obtained with the Yacoub procedure., (Copyright © 2022. Published by Elsevier B.V.)

Information storage is a key element of autonomous, out-of-equilibrium dynamics, especially for biological and synthetic active matter. In synthetic active matter however, the implementation of internal memory in self-propelled systems is often absent, limiting our understanding of memory-driven dynamics. Recently, a system comprised of a droplet generating its guiding wavefield appeared as a prime candidate for such investigations. Indeed, the wavefield, propelling the droplet, encodes information about the droplet trajectory and the amount of information can be controlled by a single scalar experimental parameter. In this work, we show numerically and experimentally that the accumulation of information in the wavefield induces the loss of time correlations, where the dynamics can then be described by a memory-less process. We rationalize the resulting statistical behavior by defining an effective temperature for the particle dynamics where the wavefield acts as a thermostat of large dimensions, and by evidencing a minimization principle of the generated wavefield., (© 2022. The Author(s).)

Background: Valve-sparing aortic root replacement (VSRR) techniques have several advantages such as preservation of physiological haemodynamics of the native aortic valve and avoidance of prosthetic valve-related complications. However, VSRR procedures are generally performed in young patients and the long-term results in elderly patients (≥65 years) are scarce., Methods: Fifty-six (56) consecutive patients underwent VSRR surgery by a single surgeon at the current centre between January 2006 and December 2013; a modified "remodelling technique" was typically performed. The mean age was 58.86±12.5 years; Marfan syndrome and bicuspid aortic valve were both present in six patients (10.7%); 38 patients (67.8%) presented with greater than moderate aortic regurgitation; and 17 patients (30.4%) were in New York Heart Association (NYHA) class III before surgery. They were divided into two groups according to their ages receiving VSRR surgery: Group E (elderly patients aged ≥65 years, n=24) and Group Y (young patients aged <65 years, n=32). The primary outcomes were aortic valve-related reoperation, cardiovascular reoperation, all-cause mortality, and functional status., Results: One (1) patient in Group E was converted to aortic valve replacement as a result of a failed aortic valve repair. No perioperative mortality was observed. The mean follow-up was 11.5±2.9 years. Aortic valve-related reoperation was noted in two patients of each group (one with endocarditis, one with severe aortic regurgitation). Cardiovascular reoperations were observed in three and six patients, and all-cause deaths in seven and two patients in Group E and Group Y, respectively. The 10-year freedom from aortic valve-related reoperation was estimated to be 91.7±5.6% and 92.7±5.0% (p=0.594), the 10-year freedom from cardiovascular reoperation was 86.4±7.3% and 81.1±7.7% (p=0.781), and the cumulative 10-year survival rates were 74.0±9.2% and 93.8±4.3% (p=0.018) in Group E and Group Y, respectively. During follow-up, 6.7% of patients were in NYHA class III and 6.4% of patients developed moderate-to-severe aortic regurgitation. Cox regression analysis failed to identify predictors for primary outcomes., Conclusion: Valve-sparing aortic root replacement can safely be performed in elderly patients with low early mortality and satisfactory long-term freedom from aortic valve-related and cardiovascular re-intervention., (Copyright © 2021. Published by Elsevier B.V.)

The dynamics of a triangular magnetocapillary swimmer is studied using the lattice Boltzmann method. We extend on our previous work, which deals with the self-assembly and a specific type of the swimmer motion characterized by the swimmer's maximum velocity centred around the particle's inverse viscous time. Here, we identify additional regimes of motion. First, modifying the ratio of surface tension and magnetic forces allows to study the swimmer propagation in the regime of significantly lower frequencies mainly defined by the strength of the magnetocapillary potential. Second, introducing a constant magnetic contribution in each of the particles in addition to their magnetic moment induced by external fields leads to another regime characterized by strong in-plane swimmer reorientations that resemble experimental observations.

Background: Left heart involvement might be a differential factor in the physiopathology and prognosis of severe tricuspid regurgitation (TR) following cardiac surgery. We aimed to compare the outcomes of isolated tricuspid valve surgery (ITVS) after congenital versus left heart-disease surgery., Methods: We retrospectively studied and followed up 58 patients who underwent ITVS for TR following cardiac surgery in our center from January 2012 to December 2017. According to the different etiologies of TR, the participants were divided into one group of TR following surgery for congenital heart diseases (CHD) (pCHD group, n=24), and another group of TR following surgery for left heart disease (pVHD group, n=34)., Results: Compared to the pCHD group, the pVHD group presented with a more advanced age (P<0.001), higher model for end-stage liver disease (MELD) score calculation (P=0.04), and higher EuroSCORE II calculation (P=0.01). In the post-operative course, the pVHD group showed a longer mechanical ventilation time (P<0.001) and longer intensive care unit stay (P=0.001). However, there was no significant difference between the two groups in in-hospital mortality (8.8% vs. 0, P=0.26), or the incidence of major adverse cardiac and cerebrovascular events (MACCE) (20.6% vs. 12.5%, P=0.47) at follow-up., Conclusions: Severe TR following surgery for left heart disease is associated with higher surgical risks and a remarkable frailty as compared to that following surgery for CHDs; however, with the development of surgical techniques and peri-operative management, ITVS can be safely performed in both conditions with promising contemporary mid-term outcomes., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/jtd-20-1787). The authors have no conflicts of interest to declare., (2020 Journal of Thoracic Disease. All rights reserved.)

Correction for 'Capillary assemblies in a rotating magnetic field' by Galien Grosjean et al., Soft Matter, 2019, DOI: .

Small objects floating on a fluid have a tendency to aggregate due to capillary forces. This effect has been used, with the help of a magnetic induction field, to assemble submillimeter metallic spheres into a variety of structures, whose shape and size can be tuned. Under time-varying fields, these assemblies can propel themselves due to a breaking of time reversal symmetry in their adopted shapes. In this article, we study the influence of an in-plane rotation of the magnetic field on these structures. Various rotational modes have been observed with different underlying mechanisms. The magnetic properties of the particles cause them to rotate individually. Dipole-dipole interactions in the assembly can cause the whole structure to align with the field. Finally, non-reciprocal deformations can power the rotation of the assembly. Symmetry plays an important role in the dynamics, as well as the frequency and amplitude of the applied field. Understanding the interplay of these effects is essential, both to explain previous observations and to develop new functions for these assemblies.

A system of ferromagnetic particles trapped at a liquid-liquid interface and subjected to a set of magnetic fields (magnetocapillary swimmers) is studied numerically using a hybrid method combining the pseudopotential lattice Boltzmann method and the discrete element method. After investigating the equilibrium properties of a single, two, and three particles at the interface, we demonstrate a controlled motion of the swimmer formed by three particles. It shows a sharp dependence of the average center-of-mass speed on the frequency of the time-dependent external magnetic field. Inspired by experiments on magnetocapillary microswimmers, we interpret the obtained maxima of the swimmer speed by the optimal frequency centered around the characteristic relaxation time of a spherical particle. It is also shown that the frequency corresponding to the maximum speed grows and the maximum average speed decreases with increasing interparticle distances at moderate swimmer sizes. The findings of our lattice Boltzmann simulations are supported by bead-spring model calculations.

We present a wave-memory-driven system that exhibits intermittent switching between two propulsion modes in free space. The model is based on a pointlike particle emitting periodically cylindrical standing waves. Submitted to a force related to the local wave-field gradient, the particle is propelled, while the wave field stores positional information on the particle trajectory. For long memory, the linear motion is unstable and we observe erratic switches between two propulsive modes: linear motion and diffusive motion. We show that the bimodal propulsion and the stochastic aspect of the dynamics at long time are generated by a Shil'nikov chaos. The memory of the system controls the fraction of time spent in each phase. The resulting bimodal dynamics shows analogies with intermittent search strategies usually observed in living systems of much higher complexity.

Objectives: This study sought to describe the procedural and clinical outcomes of patients undergoing transcarotid (TC) transcatheter aortic valve replacement (TAVR) with the Edwards Sapien 3 device., Background: The TC approach for TAVR holds the potential to become the optimal alternative to the transfemoral gold standard. Limited data exist regarding safety and efficacy of TC-TAVR using the Edwards Sapien 3 device., Methods: The French Transcarotid TAVR prospective multicenter registry included patients between 2014 and 2018. Consecutive patients treated in 1 of the 13 participating centers ineligible for transfemoral TAVR were screened for TC-TAVR. Clinical and echocardiographic data were prospectively collected. Perioperative and 30-day outcomes were reported according to the updated Valve Academic Research Consortium (VARC-2)., Results: A total of 314 patients were included with a median (interquartile range) age of 83 (78 to 88) years, 63% were males, Society of Thoracic Surgeons mortality risk score 5.8% (4% to 8.3%). Most patients presented with peripheral artery disease (64%). TC-TAVR was performed under general anesthesia in 91% of cases, mostly using the left carotid artery (73.6%) with a procedural success of 97%. Three annulus ruptures were reported, all resulting in patient death. At 30 days, rates of major bleeding, new permanent pacemaker, and stroke or transient ischemic attack were 4.1%, 16%, and 1.6%, respectively. The 30-day mortality was 3.2%., Conclusions: TC-TAVR using the Edwards Sapien 3 device was safe and effective in this prospective multicenter registry. The TC approach might be considered, in selected patients, as the first-line alternative approach for TAVR whenever the transfemoral access is prohibited. Sapien 3 device was safe and effective in our multicenter cohort., (Copyright © 2019. Published by Elsevier Inc.)

A paradigmatic microswimmer is the three-linked-spheres model, which follows a minimalist approach for propulsion by shape shifting. As such, it has been the subject of numerous analytical and numerical studies. In this Rapid Communication, an experimental three-linked-spheres swimmer is created by self-assembling ferromagnetic particles at an air-water interface. It is powered by a uniform oscillating magnetic field. A model, using two harmonic oscillators, reproduces the experimental findings. Because the model remains general, the same approach could be used to design a variety of efficient microswimmers.

When ferromagnetic particles are suspended at an interface under magnetic fields, dipole-dipole interactions compete with capillary attraction. This combination of forces has recently given promising results towards controllable self-assemblies as well as low-Reynolds-number swimming systems. The elementary unit of these assemblies is a pair of particles. Although equilibrium properties of this interaction are well described, the dynamics remain unclear. In this paper, the properties of magnetocapillary bonds are determined by probing them with magnetic perturbations. Two deformation modes are evidenced and discussed. These modes exhibit resonances whose frequencies can be detuned to generate nonreciprocal motion. A model is proposed that can become the basis for elaborate collective behaviors.

Propagation-based imaging or inline holography in combination with computed tomography (holotomography) is a versatile tool to access a sample's three-dimensional (3D) micro or nano structure. However, the phase retrieval step needed prior to tomographic reconstruction can be challenging especially for strongly absorbing and refracting samples. Near-field ptychography is a recently developed phase imaging method that has been proven to overcome this hurdle in projection data. In this work we extend near-field ptychography to three dimensions and we show that, in combination with tomography, it can access the nano structure of a solid oxide fuel cell (SOFC). The quality of the resulting tomographic data and the structural properties of the anode extracted from this volume were compared to previous results obtained with holotomography. This work highlights the potential of 3D near-field ptychography for reliable and detailed investigations of samples at the nanometer scale, with important applications in materials and life sciences among others.