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The geometry of retinal layers is an important imaging feature for the diagnosis of some ophthalmic diseases. In recent years, retinal layer segmentation methods for optical coherence tomography (OCT) images have emerged one after another, and huge progress has been achieved. However, challenges due to interference factors such as noise, blurring, fundus effusion, and tissue artifacts remain in existing methods, primarily manifesting as intra-layer false positives and inter-layer boundary deviation. To solve these problems, we propose a method called Tightly combined Cross-Convolution and Transformer with Boundary regression and feature Polarization (TCCT-BP). This method uses a hybrid architecture of CNN and lightweight Transformer to improve the perception of retinal layers. In addition, a feature grouping and sampling method and the corresponding polarization loss function are designed to maximize the differentiation of the feature vectors of different retinal layers, and a boundary regression loss function is devised to constrain the retinal boundary distribution for a better fit to the ground truth. Extensive experiments on four benchmark datasets demonstrate that the proposed method achieves state-of-the-art performance in dealing with problems of false positives and boundary distortion. The proposed method ranked first in the OCT Layer Segmentation task of GOALS challenge held by MICCAI 2022. The source code is available at https://www.github.com/tyb311/TCCT.

Abstract: The motion of spiral waves in excitable media driven by a weak pacing around the spiral tip is investigated numerically as well as theoretically. We presented a Bifurcations diagram containing four types of the spiral motion induced by different frequencies of pacing: rigidly rotating, inward-petal meandering, resonant drift, and outward-petal meandering spiral. Simulation shows that the spiral resonantly drifts when the frequency of pacing is close to that of the spiral rotation. We also find that the speed and direction of the drift can be efficiently controlled by means of the strength and phase of the local pacing, which is consistent with analytical results based on the framework of the weak deformation approximation.

From the perspective of transportation resource allocation efficiency, it is significant to explore the impact of transportation resource allocation efficiency on urban low-carbon development, which is of theoretical guidance value and practical significance to help China achieve the dual-carbon goal as soon as possible. This paper takes the panel data of 30 provinces (autonomous regions and municipalities) from 2008 to 2021 as samples, adopts the entropy value method and the entropy weight TOPSIS method to measure the level of urban low-carbon development, and utilizes the super-efficiency SBM model to measure the efficiency of transportation resource allocation. The benchmark regression model is used to analyze the direct impact of transportation resource allocation efficiency on urban low-carbon development, and per capita carbon emission is selected as the mediating variable for mechanism analysis. It is found that transportation resource allocation efficiency has a significant positive impact on urban low-carbon development. In addition, the mechanism test shows that transportation resource allocation efficiency can promote low-carbon urban development by reducing per capita carbon emissions. Lastly, the impact of transportation resource allocation efficiency on urban low-carbon development contributes significantly to the eastern, western, and less developed regions.

The alkali-free surfactant–polymer flooding system with ultralow interfacial tensions is still a challenge to enhance oil recovery at present. In this study, a new thermally stable and salt tolerant biopolymer (HS-EPS) was obtained from thje broth of Sphingomonas sp.HS, a newly isolated strain (CGMCC No. 22954). Compared to HPAM, the elasticity of HS-EPS was dominant which is conducive to enhancing oil recovery. The HS-EPS showed good viscosity stability at salinities up to 360 g/L of NaCl, 60 g/L of Ca2+, and 60 g/L of Mg2+, temperatures up to 90 °C, and pH 4–10. Meanwhile, a new alkali-free surfactant–polymer binary system was developed using HS-EPS and a biobased surfactant newly synthesized in our laboratory. The interfacial tension between this binary flooding system and Daqing crude oil was below 10–2mN/m with 100 g/L of NaCl, 400 mg/L of Ca2+, or at a temperature of 80 °C. In addition, this binary system possesses a good oil sand adsorption resistance, dilution resistance, and aging stability. These results demonstrate that the new biopolymer HS-EPS secreted by Sphingomonas sp. HS is promising in oil recovery in the alkali-free flooding system.

To investigate the relationship between starch hydrolysis and Monascuspigments (MPs) production, the α-amylase gene (AOamyA) from Aspergillus oryzaewas heterologously expressed in Monascus ruberCICC41233, and we obtained a positive transformant named Monascus ruberAmy9. In M. ruberAmy9, the α-amylase activities were 6.65- and 4.26-fold higher at 72 h and 144 h, respectively, than those in the parent strain with the glucose as solo carbon medium. Surprisingly, in the MPs fermentation medium with rice powder as solo material, M. ruberAmy9 completely degraded starch at 48 h, while 43.93 and 7.29 mg/mL starch remained at 48 and 144 h, respectively, in the parent strain. Monascus ruberAmy9 accelerated starch hydrolysis, which enhanced biomass and also increased total MPs by 132% after 144 h. Compared with M. ruberCICC41233, the relative gene expression levels, as determined by a quantitative real-time polymerase chain reaction analysis, of acl2encoding ATP-citrate lyase subunit 2, pksencoding polyketide synthase, and fasBencoding the fatty acid synthase beta subunit increased by 33.14, 145.18, and 32.15%, respectively, after 144 h in M. ruberAmy9. The up-regulated expression of these key genes in MPs synthesis contributed to the large increase in MPs production. This interesting work provided us with a new idea and a new target for the study of the MPs production.

The right internal jugular vein (IJV) is an important access site for hemodialysis catheterization. Venous cannulation failure is usually caused by central venous stenosis and is rarely related to vessel malformation. We herein present a case of failure to place a tunneled hemodialysis catheter into the right IJV. The patient had an arteriovenous fistula in the right arm with inadequate flow and a history of multiple central venous catheterizations. The guidewire was repeatedly misplaced into the right subclavian vein (SV) regardless of the technique used. Computed tomography venography revealed that the inferior segment of the right IJV drained into the ipsilateral SV. To the best of our knowledge, this is the first report of catheterization failure due to abnormal drainage of the right IJV into the ipsilateral SV.