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Ventricular septal defect (VSD) is one of the commonest congenital heart diseases (CHDs). Current occluders for VSD treatment are mainly made of nitinol, which has the risk of nickel allergy, persistent myocardial abrasion and fatal arrythmia. Herein, a fully biodegradable polydioxanone (PDO) occluder equipped with a shape line and poly-l-lactic acid PLLA membranes is developed for VSD closure without the addition of metal marker. PDO occluder showed great mechanical strength, fatigue resistance, geometry fitness, biocompatibility and degradability. In a rat subcutaneous implantation model, PDO filaments significantly alleviated inflammation response, mitigated fibrosis and promoted endothelialization compared with nitinol. The safety and efficacy of PDO occluder were confirmed in a canine VSD model with 3-year follow-up, demonstrating the biodegradable PDO occluder could not only effectively repair VSD, induce cardiac remodeling but also address the complications associated with metal occluders. Furthermore, a pilot clinical trial with five VSD patients indicated that all the occluders were successfully implanted under the guidance of echocardiography and no adverse events occurred during the 3-month follow-up. Collectively, the fully bioresorbable PDO occluder is safe and effective for clinical VSD closure and holds great promise for the treatment of structural CHDs.

The eating quality of rice is a trait of high interest to breeders and consumers, but the existing detection methods are damaging, time consuming, or subjective. The composition and physicochemical properties in breeding are closely related to the eating quality, and near-infrared spectroscopy (NIRS) is a rapid and nondestructive detection method. In this study, we established NIRS models for the composition (amylose, protein, and fat content) and physicochemical properties (gel consistency and alkali spreading value) of rice grains. The model determination coefficients were > 0.86 and were analyzed for 112 japonica rice. The results showed that the composition and physicochemical properties were highly correlated with the eating quality of japonica rice. High eating quality with soft and sticky cooked rice had lower amylose content, lower protein content, higher fat content, higher gel consistency, and higher alkali-spreading value. A rapid and nondestructive evaluation method for eating quality using rice grains was developed with related composition and physicochemical properties, and the determination coefficient of predicted eating quality and traditional sensory evaluation score was 0.8741. Thus, the proposed method enables effective screening of desired eating quality according to different compositions and physicochemical, and eating qualities based on NIRS without preprocessing rice grains (with husk) in early generation breeding, which can shorten the breeding period.

Despite the great success achieved by the exploitation of heterosis in rice, the genetic basis of heterosis is still not well understood. We adopted an advanced-backcross breeding strategy to dissect the genetic basis of heterosis for yield and eight related traits. Four testcross (TC) populations with 228 testcross F1combinations were developed by crossing 57 introgression lines with four types of widely used male sterile lines using a North Carolina II mating design. Analysis of variance indicated that the effects of testcross F1combinations and their parents were significant or highly significant for most of the traits in both years, and all interaction effects with year were significant for most of the traits. Positive midparent heterosis (HMP) was observed for most traits in the four TC populations in the two years. The relative HMPlevels for most traits varied from highly negative to highly positive. Sixty-two dominant-effect QTL were identified for HMPof the nine traits in the four TC populations in the two years. Of these, 22 QTL were also identified for the performance of testcross F1. Most dominant-effect QTL could individually explain more than 10% of the phenotypic variation. Four QTL clusters were observed including the region surrounding the RM9–RM297 region on chromosome 1, the RM110–RM279–RM8–RM5699–RM452 region on chromosome 2, the RM5463 locus on chromosome 6 and the RM1146–RM147 region on chromosome 10. The identified QTL for heterosis provide valuable information for dissecting the genetic basis of heterosis.

• A high-order model considering shear deformation and thickness stretching effect is established to investigate the bending and buckling responses of porous FG curved nanobeam. • The governing equation is derived based on the consistent two-phase local/non-local stress gradient theory, and the analytical solution of curved nanobeams is obtained by Navier's method. • The difference of buckling mode sensitivity between curved characteristics, scale effect and thickness stretching effect of the curved beam is analyzed. In this work, we provide an analysis of the bending and buckling properties of functionally graded (FG) nanobeams with trigonometric function-dependent porosity distribution. Herein, a high-order curved nanobeam model considering both shear deformations and thickness stretching effect is established. Two-phase local/nonlocal stress-driven gradient theory is utilized to capture small-scale effects. Hamilton's principle is adopted to obtain the governing equation and boundary conditions, and the analytical solutions, such as exact formulas for lateral displacement and critical buckling load are obtained by employing Navier's method for simply supported boundary conditions. Furthermore, the effects of local volume fraction, nonlocal parameter, material length scale parameter, shear deformation, material distribution, and porosity distribution pattern in stress-driven models are analyzed in detail. The parametric studies indicate that the thickness stretching effect has a different influence on bending and buckling. In addition, the thickness stretching effect and the opening angle show different coupling mechanisms during bending and buckling. On the other hand, the higher-order buckling mode leads to a more significant scale effect and thickness tensile effect, but reduces the influence of the opening angle. Finally, we find that due to the coupling effect between the pore distribution pattern and the orientation bias of the FG nanobeam, the variation of the material gradient index leads to a different order of the dimensionless critical buckling loads predicted by the three pore distributions. [ABSTRACT FROM AUTHOR]