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Laparoscopic gastrectomy for advanced gastric cancer (GC) has been applied more frequently worldwide but is still controversial for patients with serosal invasion (T4a). This study compared short- and long-term outcomes of laparoscopic distal radical gastrectomy (LDG) with open distal gastrectomy (ODG) for T4a GC.We retrospectively studied 472 patients with T4a gastric adenocarcinoma in the lower or middle third of the stomach: 231 underwent LDG and 241 underwent ODG between 2013 and 2020. Short-term outcomes included operative characteristics and complications. Long-term outcomes included overall survival (OS) and disease-free survival (DFS). Propensity score-matched (PSM) analysis was used to adjust for imbalances in baseline characteristics between groups.The PSM strategy resulted in 294 patients (147 in each group). The LDG group had a significantly longer operating time (mean: 200 vs 190 min, p = 0.001) but reduced blood loss (mean: 50 vs 100 ml, p = 0.001). The LDG group had a higher rate of any postoperative complication (23.1% vs 12.2%, p = 0.021) but most were classified as grades I-II according to Clavien-Dindo classification. Grade III-V complications were similar between groups. Five-year OS was 69% versus 60% (p = 0.109) and 5-year DFS was 58% vs 53% (p = 0.3) in LDG and ODG groups, respectively. For tumor size5 cm, LDG was better in reduction of blood loss, postoperative hospital length of stay, and OS.LDG is feasible and safe for patients with T4a GC and is comparable to ODG regarding short- and long-term outcomes. Furthermore, LDG can be a favorable option for T4a GC smaller than 5 cm.

In this paper, a new state called superposition of three-mode photon-added trio coherent state is introduced and its nonclassical properties are studied. Based on the negative values of the Wigner function, we find that the nonclassical as well as non-Gaussian characteristics of the superposition of three-mode photon-added trio coherent state are more obvious than that of the original trio coherent state. The superposition of three-mode photon-added trio coherent state always appears three-mode sum squeezing while the trio coherent state does not. It also shows that the superposition of three-mode photon-added trio coherent state is genuinely entangled. The entanglement degree of this state is more improved compared with the trio coherent state. It becomes bigger and bigger through nonlocally increasing the number of added photons.

This paper studies the higher-order nonclassical and entanglement properties in the photon-added trio coherent state (PATCS). We use the criterion of higher-order single-mode antibunching to evaluate the role of the photon addition operation. Furthermore, the general criteria for detection of higher-order three-mode sum squeezing and entanglement features in the PATCS are also investigated. The results show that the photon addition operation to a trio coherent state can enhance the degree of both the higher-order single-mode antibunching and the higher-order three-mode sum squeezing and enlarge the value of the higher-order three-mode entanglement factor in the photon-added trio coherent state. In addition, the manifestation of the single-mode antibunching and the entanglement properties are more obvious with increasing the higher values of orders.

Laparoscopic proximal gastrectomy (LPG) has been a standard surgery for early gastric cancer in the upper third of the stomach and large esophagogastric junction gastrointestinal stromal tumor. However, how to reconstruct the stomach after LPG is still debated. This study aimed to evaluate the results of LPG with double-flap reconstruction.A retrospective study was performed with 14 patients undergoing LPG with double-flap reconstruction for early gastric cancer or large tumors in the upper third of the stomach from 2018 to 2021. We evaluated postoperative complications, gastroesophageal reflux and the gastric remnant's function using endoscopy in accordance with the Los Angeles and Residue-Gastritis-Bile classifications, and patients' quality of life by the Gastrointestinal Symptom Rating Scale (GSRS) questionnaire.Median age was 54 years and 10 patients were male. There were 7 patients with gastrointestinal stromal tumor, 4 with leiomyoma and 3 with early-stage adenocarcinoma. No patient had major complications or required conversion to open surgery. During a median follow-up period of 24.6 months, 1 patient had late anastomotic stricture, 2 had metastasis, and 1 died. Endoscopic evaluation at 6 and 12 months showed good function of the gastric remnant in most patients. Patients' quality of life improved over time: mean GSRS score was 26.9±12.6, 20.3±7.2, and 18.8±4.2 at 6, 12, and 24 months, respectively.LPG with double-flap reconstruction is feasible and safe for early gastric cancer or large tumors in the upper third of the stomach. The long-term functional outcomes and patients' quality of life were acceptable.

We describe in this paper our deep learning-based approach for the EndoCV2020 challenge, which aims to detect and segment either artefacts or diseases in endoscopic images. For the detection task, we propose to train and optimize EfficientDet—a state-of-the-art detector—with different EfficientNet backbones using Focal loss. By ensembling multiple detectors, we obtain a mean average precision (mAP) of 0.2524 on EDD2020 and 0.2202 on EAD2020. For the segmentation task, two different architectures are proposed: UNet with EfficientNet-B3 encoder and Feature Pyramid Network (FPN) with dilated ResNet-50 encoder. Each of them is trained with an auxiliary classification branch. Our model ensemble reports an sscore of 0.5972 on EAD2020 and 0.701 on EDD2020, which were among the top submitters of both challenges.

In this paper, adsorbents composed of reduced graphene oxide–CoFe2O4 ferrite–polyaniline (RGO/CF/PANI) nanocomposites have been synthesized by different techniques, namely, hydrothermal, graphite exfoliation, reduction, and polymerization. The adsorbents were characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and vibrating sample magnetometer. The adsorption of uranium (VI) could be well described by the Langmuir and the pseudosecond-order models. The highest adsorption capacity of the composites for uranium (VI) was evaluated to be 2430 mg/g at pH = 5 and 25 °C. The uranium loaded RGO/CF/PANI could be readily separated from aqueous solutions by an external magnetic field. This paper demonstrates an efficient and convenient approach for the adsorption of uranium (VI) from aqueous solutions.

Reduced graphene oxide-Cu0.5Ni0.5Fe2O4-polyaniline nanocomposite (RGO-CNF-PANI) was synthesized by a three-step method. The morphology, structure and magnetic properties of composite samples were characterized by scanning electron microscopy, x-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy (RAMAN) and vibrating sample magnetometer. It was found that reduced graphene oxide was exfoliated and decorated homogeneously with ferrite nanoparticles having diameters between 11 nm and 21 nm. The polyaniline was coated by an in situ chemical oxidation polymerization. The measurement of magnetic properties found the remanence (Mr) and coercive field (Hc) were near zero, indicating that the obtained material was superparamagnetic. The microwave measurements found that the nanocomposite exhibited a good absorption property with the optimum matching thickness of 3 mm in the frequency of 8–12 GHz. The value of the maximum RL was −40.7 dB at 9.8 GHz.

Trio coherent states as a kind of three-mode entangled state were introduced and studied. Some nonclassical characteristics of them such as higher-order antibunching, three-mode sum-squeezing and intermodal entanglement have been well revealed. In this paper, we further confirm their nonclassicality by examining negativity of Wigner function and non-Gaussian feature. However, our main purpose is to show that all the above-mentioned quantum properties of the trio coherent state can be enhanced by simultaneously adding photons to each mode of the state. In particular, we demonstrate that such so-called photon-added trio coherent states can possess three-mode sum-squeezing while the original trio coherent state (without photon-addition) cannot. In general, we show analytically and graphically how the degree of nonclassicality and/or entanglement depends on the number of added photons. Furthermore, we also consider a beamsplitter-based scheme for generation of the photon-added trio coherent states and evaluate the fidelity as well as the success probability as functions of the beamsplitter's parameter and the number of added photons.

We examine the higher-order nonclassical properties of the even and odd charge coherent states as well as proposing a scheme to generate these states whose modes can freely travel in open space. We show that the even and odd charge coherent states exhibit both higher-order antibunching and higher-order squeezing. While the two-mode higher-order antibunching occurs in any order and essentially depends on the charge number, the two-mode higher-order squeezing appears only in the even orders. We also prove that these states are genuinely entangled, and they can be generated by means of cross-Kerr media, beam splitters, phase shifts and threshold detectors. We find that the fidelity and the corresponding success probability to generate these states are dependent on the correlative parameters.

The concept of nonlinear charge pair cat states is introduced and their higher-order nonclassical properties are studied. By comparing the nonlinear cases of photon-added states f_2(n) and a laser-driven trapped ion f_3(n) with the linear case f_1(n), it is shown that these states exhibit two-mode higher-order antibunching to all orders and the degree of antibunching depends on the suitable variables, especially on the nonlinear functions. We also show that in such states, the higher-order squeezing appears only in the even orders and the squeezing behaviours for the nonlinear cases f_2(n) and f_3(n) are quite opposite. These states are two-mode genuinely entangled regardless of the nonlinear functions and their entanglement properties are more obvious in the photon-added states f_2(n) case.

Cu0.5Ni0.5Fe2O4 – reduced graphene oxide composites (CNF-rGO) as an efficient adsorbent for the adsorption of uranium (VI) have been synthesized by a two-steps methods. The structures and the physicochemical properties of adsorbents are characterized by Scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy (RAMAN) and Vibrating sample magnetometer (VSM) measurement. It was found that rGO were exfoliated and decorated homogeneously with CNF nanoparticles having diameters of 20 nm. The saturated magnetization (Ms) value was estimated to be 60 emu/g, remanences (Mr) and coercive forces (Hc) near to zero, indicating that obtained material is superparamagnetic. The pH effect, contact time and adsorption isotherms were examined in batch experiments. The adsorption isotherm agreed well with the Langmuir model, having a maximum adsorption capacity of 256 mg/g, at pH = 6, T = 298 K.

NiFe2O4 superparamagnetic nanoparticles have been prepared by the method of spraying - co-precipitation subsequent by hydrothermal treatment. This procedure allowed to produce efficiently nanoparticles with high performances. Different techniques such as XRD, TEM, EDX, VSM were used to investigate the morphology, structure and magnetic properties of the obtained materials. It is shown that the materials have face-centered cubic trevorite structure, and their degree of crystallinity and magnetic properties improved with increasing temperature and time of hydrothermal treatment. After 32 hours of hydrothermal treatment at 160°C, NiFe2O4 nanomaterial has particle size of about 23 nm and saturation magnetization (Ms) of 49 emu/g.

Trio coherent states (TCSs) are non-Gaussian three-mode entangled states which can serve as a useful resource for continuous-variable quantum tasks, so their generation is of primary importance. Schemes exist to generate stable TCSs in terms of vibrational motion of a trapped ion inside a crystal. However, to perform quantum communication and distributed quantum computation the states should be shared beforehand among distant parties. That is, their modes should be able to be directed to different desired locations in space. In this work, we propose an experimental setup to generate such free-traveling TCSs in terms of optical fields. Our scheme uses standard physical resources, such as coherent states, balanced beam splitters, phase shifters, nonideal on-off photodetectors, and realistic weak cross-Kerr nonlinearities, without the need of single photons or homodyne or heterodyne measurements. We study the dependences of the fidelity of the state generated by our scheme with respect to the target TCS and the corresponding generation probability for the parameters involved. In theory, the fidelity could be nearly perfect for whatever weak nonlinearities $\ensuremath{\tau}$ and low photodetector efficiency $\ensuremath{\eta}$, provided that the amplitude $|\ensuremath{\alpha}|$ of an input coherent state is large enough, namely, $|\ensuremath{\alpha}|\ensuremath{\ge}5/(\sqrt{\ensuremath{\eta}}\ensuremath{\tau})$.

During traffic loads on pavements, in order to study the behavior of rigid pavements and the bottom-up crack phenomenon on semi-rigid pavement, it is essential to predict the stress state near cracks. Classical simplified models used in the pavement design method are, from this point of view, poorly adapted; moreover, current numerical solutions involving 3D finite element calculations require very fine meshes, which can be very time-consuming. For these calculations, it is proposed herein to adapt a simplified elastic multilayer model to the mechanic study of pavements. Such a model reduces the 3D real problem by one dimension and produces regular stress field near cracks at the interface of two different layers. The semi-infinite soil is modeled with the help of Boussinesq equations. All the equations are solved numerically under Matlab. Validation is successfully carried out by means of comparison with 3D finite element computations., Pour étudier le comportement des chaussées rigides et la remontée des fissures sur chaussées semi-rigides en vue de leurs renforcements, il faut pouvoir prédire l'état des contraintes au voisinage d'une fissure sous les sollicitations du trafic. Les modèles simplifiés usuels de dimensionnement des chaussées sont à cet égard peu adaptés et les solutions numériques actuelles par éléments finis 3D nécessitent des maillages très fins, coûteux en temps de calcul. Pour ces calculs, on propose ici l'adaptation d'un modèle simplifié de multicouches élastiques à la mécanique des chaussées. Ce modèle permet de réduire d'une dimension le problème réel et de rendre finies les valeurs des contraintes près des bords ou des fissures. Le massif de sol semi-infini est traité comme un massif élastique de Boussinesq. La résolution numérique est programmée sous Matlab. La validation est effectuée, avec succès, par comparaison avec des calculs par éléments finis 3D.

Cracking in pavements, LIMOGES, FRANCE, 05-/05/2004 - 08/05/2004; International audience; The French pavement design method uses the 2D axi-symmetric structural analysis of Burmister's model [1]. This model calculates almost analytically and efficiently a multi-layer on a solid half space soil subjected to a circular load. However, to take into account pavement degradations as cracks in the structure, for concrete and bituminous pavements, the design method requires other models. They can be modelled by using 3D finite element methods, but such calculations can be very time-consuming. To make a proper analysis of crack initiation and propagation in pavement structures, we propose to use a simplified plate model linked to the Boussinesq model for the soil. This approach produces regular stress fields near cracks at the interface of two different layers. The resolution is carried out numerically under Matlab [2]. This model gives, very quickly, good approximations of the design stress fields near interfaces and cracks in comparison with finite element calculations. In the aim to simulate some fatigue problems, a method is presented to accelerate the calculations. It consists in writing the 3D problem in a form without dimension. Then, the evolution of the main fields can be obtained with a "table of results" that has been built.

5th international CROW-workshop on fundamental modelling of the design and performance of concrete pavements , ISTANBUL, TURQUIE, 31-/03/2004 - 02/04/2004; Pavement degradations are not directly taken into account in current pavement design methods (de Lurdes Antunes, 2002). They can be modeled using 3D finite element methods, but such calculations can be very time-consuming. To make a proper analysis of crack initiation and propagation in asphalt or concrete pavement structures, we propose to use a simplified plate model linked to the Boussinesq model for the soil (Johnson, 1992). This simplified model is built with a polynomial approximation of stress fields for each layer (Chabot, 1997) (Chabot et Ehrlacher, 1998). It introduces, as variables, stresses defined at each interface and leads to a 2D model. It can be viewed as superposition of Reissner's plates linked together by interface forces. The stress fields obtained are very close to those given by 3D finite elements (Carreira et al., 1998). This approach is very fast and produces regular stress fields near cracks at the interface of two different layers. Equations are solved numerically under Matlab. Results are compared successfully with finite element calculations on 3D pavements and 2D cracked pavements.

International audience

Most of design pavement models can not be used to simulate cracking in pavements. This problem can be modelled by using 3D finite element methods, but such calculations can be very time-consuming. In the objective to build a software for the evaluation of cracked pavements, and design solution for rehabilitation, we propose here to use a simplified plate model for bending problem linked to the Boussinesq model for the soil. The complete algorithm is programmed in the Matlab software. This model gives, very quickly, good approximations of the design stress fields near interfaces and vertical cracks in comparison with 3D finite element calculations. Thermal and shrinkage problem are studied and validated. In the aim to simulate some fatigue problems, a method is presented to accelerate the calculations., Les modèles simplifiés usuels de dimensionnement des chaussées ne permettent pas de modéliser des chaussées fissurées et une modélisation par éléments finis 3D peut s'avérer très lourde. Dans l'objectif de construire un outil rapide et efficace de diagnostic et d'entretien des chaussées dégradées par le trafic, un modèle simplifié est proposé. Ce modèle repose sur un modèle simplifié adapté aux problèmes de flexion, le modèle multiparticulaire des matériaux multicouches (M4) à 5n équations (n: nombre total de couches) et le modèle élastique de Boussinesq pour le massif de sol. Programmé sous Matlab, dans le cas de bicouches de chaussées fissurées verticalement, ce modèle donne très rapidement d'excellents résultats par comparaison avec des calculs éléments finis 3D. Les cas de chargement de retrait thermique et de gradient thermique sont intégrés dans la modélisation et validés. Pour accélérer encore plus l'obtention des solutions dans le cadre de calculs multi- cycles, une méthode d'extrapolation des résultats du 2D pour estimer le 3D est exposée.

For the design of the repairs, the investigation of reflective cracking in the roadways made up of bituminous mixtures, the study of concrete pavements, it is useful to predict stress fields in a cracking pavement subjected to the traffic of heavy lorries. The classical elastic model of multi-layer used by the French design method of roadways is unsuited to take into account these defects. The use of 3D finite element method can be rather heavy. In this paper, a simplified elastic model is used to study cracks in pavements. This model makes it possible to decrease by one dimension the real problem. It returns finite values of the stress fields close to edges or cracks. The elastic analytical equations of Boussinesq are used for modelling the half-space soil. The resolution is carried out numerically under Matlab. Results are compared successfully with finite element calculations on cracking (or not) pavements., Pour le dimensionnement des solutions d'entretien des chaussées semi-rigides, et en particulier l'étude de la remontée des fissures provenant des couches de matériaux liés aux liants hydrauliques dans les couches bitumineuses, il faut pouvoir prédire l'état des contraintes au voisinage d'une fissure sous les sollicitations du trafic. Le modèle élastique préconisé par la méthode française de dimensionnement de chaussées est inadapté à la prise en compte des défauts dans le cadre d'une modélisation numérique de type éléments finis. Nous proposons ici l'adaptation d'un modèle simplifié (M4-5n) de multicouches élastiques à la mécanique des chaussées. Ce modèle permet de réduire d'une dimension le problème réel et de rendre finies les valeurs de contraintes près des bords. Le massif de sol semi-infini est traité comme un massif élastique de Boussinesq. La résolution numérique est programmée sous Matlab et la validation est faite, avec succès, par comparaison avec des calculs EF CESAR.