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The purpose of this study is to explore the application value of two‐dimensional ultrasound and shear wave elastography (SWE) in the multidimensional evaluation of diastasis recti abdominis (DRA) during different gestational periods. A cohort of 202 gravidas that were examined in our hospital between June 2021 and September 2022 were selected for the purpose of the study, which included 26 cases with <14 weeks of pregnancy, 36 cases in the 14th–27th week of pregnancy, 36 cases in the 28th–34th week of pregnancy, 32 cases in the 35th–38th week of pregnancy, 45 cases at 42 days postpartum, and 27 cases at 3 months postpartum. The inter‐rectus distance (IRD) and the thickness in each gestational period were measured, and Young's modulus of the rectus abdominis at different gestational periods was measured using SWE by two sonographers. The differences in IRD, thickness, and elasticity characteristics during different periods, and the correlation between rectus abdominis elasticity and IRD, thickness, body mass index (BMI), neonatal weight, and delivery mode were analyzed and compared. The consistency of SWE parameters obtained by different sonographers was also compared. There were significant differences in IRD, thickness, and Young's modulus during different gestational periods (P= .000, P< .001, P< .001). Early postpartum IRD and Young's modulus did not restore to the level of early pregnancy (P< .001, P< .001), while the thickness of rectus abdominis was not significantly different from that of early pregnancy (P= .211). The Young's modulus of rectus abdominis was negatively correlated with the IRD (r= .515), positively correlated with the thickness of rectus abdominis (r= .408), and weakly negatively correlated with maternal BMI (r= −.296). There was no significant correlation with neonatal weight or delivery mode (P= .147, .648). The Bland–Altman plot showed that the two sonographers had good consistency in evaluating the elasticity of rectus abdominis by SWE. The multidimensional evaluation of DRA by ultrasound is feasible and IRD and Young's modulus can be used to evaluate the postpartum recovery of DRA. The combination of the two can objectively reflect the severity of DRA morphology and function.

Micro-TATB particles with different sizes and 3D nanoporous TATB architectures with different specific surface areas were prepared through recrystallization to study short pulse duration shock initiation properties by electric gun technology. For micro-TATB, the initiation threshold significantly decreases with TATB average size ranging from 79.7 μm to 0.5 μm. For 3D nanoporous TATB architecture, the initiation threshold decreases and then increases with specific surface areas increased from 9.6 m2/g to 36.2 m2/g. The lowest initiation thresholds are obtained for the micro-TATB with average sizes of 1.3 μm and 0.5 μm, and 3D nanoporous TATB architecture with specific surface area of 22.4 m2/g. The shock initiation thresholds of micro-TATB and 3D nanoporous TATB architectures show significantly decreases with the porosity increased. The decomposition reaction and thermal conductivity properties were further investigated to understand the initial response mechanism. High porosity provides more collapse sites to generate high temperature for formation of hot spots. The low thermal conductivity and decomposition temperature could enhance the formation and ignition of the hot spots, and initial decomposition reaction of TATB. The effect of the decomposition temperature is higher than that of the thermal conductivity on the shock initiation properties. The enhanced decomposition reaction could promote energy release and transfer process from the ignition to the combustion. This work offers a new insight to understand the effects of microstructure on the shock initiation properties and the initial response mechanism of TATB.

In the past decade, boron neutron capture therapy utilizing an accelerator-based neutron source (ABNS) designed primarily for producing epithermal neutrons has been implemented in the treatment of brain tumors and other cancers. The specifications for designing an epithermal beam are primarily based on the IAEA-TECODC-1223 report, issued in 2001 for reactor neutron sources. Based on this report, the latest perspectives and clinical requirements, we designed an ABNS capable of adjusting the average neutron beam energy. The design was based on a 2.8 MeV, 20 mA proton beam bombarding a lithium target to produce neutrons that were subsequently moderated and tuned through a tunable beam shaping assembly (BSA) which can modify the thicknesses and materials of the coin-shaped moderators, back reflectors, filters, and collimators. The simulation results demonstrated that epithermal neutron beams for deep seated tumor treatment, which were generated by utilizing magnesium fluoride with lengths ranging between 28 and 36 cm as the moderator, possessed a treatment depth of 5.6 cm although the neutron flux peak shifts from 4.5 to 1.0 keV. When utilizing a thinner moderator, a less accelerated beam power can meet the treatment requirements. However, higher powers reduced the treatment time. In contrast, employing a thick moderator can reduce the skin dose. In scenarios that required relatively low energy neutron beams, the removal of the thermal neutron filter can raise the thermal neutron flux at the beam port. And the depth of the dose rate peak could be adjusted between 0.25 and 2.20 cm by combining magnesium fluoride and polyethylene coins of different thicknesses. Hence, this device has a better adaptability for the treatment of superficial tumors. Overall, the tunable BSA provides greater flexibility for clinical treatment than common BSA designs that can only adjust the port size.

The investigation on proteinlike specific functions of nanoparticles (NPs) has been a huge challenge. Here, the biocompatibility of Au nanoparticles (AuNPs) to antigens hen egg white lysozyme and epidermal growth factor receptor was studied first by molecular dynamics (MD) simulations and the research results revealed that antigens could form quickly a stable binding with the AuNPs and kept the structural integrity of the protein, which demonstrated better biocompatibility of AuNPs. Then, two types of complementary-determining regions (CDRs) were grafted onto the AuNPs to design a novel multi-CDR-functional nanobody. By means of MD simulations under physiological conditions, we found that the bindings of the designed nanobody and the antigens were stable and safe. Compared with the results of antigens interacting with the natural antibody, the redundant CDRs on AuNPs bound with the nonactive site in the antigens to form a stable conformation, which leaded to the powerful binding capacity of the designed nanobody than that of the natural antibody. This study provided available insights into the biocompatibility of AuNPs and important theoretical proofs to the multi-CDR-functional nanobody applied in biological systems, which were expected to help in design of novel multifunctional nanobodies.

AbstractBromodomain-containing protein 9 (BRD9) has been employed as a potential target for anticancer drugs in recent years. In this work, molecular docking, molecular dynamics (MD) simulations, binding free energy calculations, and per residue energy decomposition approaches were performed to elucidate the different binding modes between four pyridinone-like scaffold inhibitors and BRD9 bromodomain. Analysis results indicate that non-polar contribution mainly deriving from van der Waals energy is a critical impact on binding affinity of inhibitors against BRD9. Some key residues Phe44, Phe47, Val49, and Ile53 (at ZA loop) enhance the binding energy of inhibitors in BRD9 by means of providing hydrophobic interactions. Moreover, it is observed that BRD9 is anchored by the formation of a stable hydrogen bond between the carbonyl of the inhibitors and the residue Asn100 (at BC loop), and a strong π–π stacking interaction formed between the residue Tyr106 (at BC loop) and the inhibitors. The existence of dimethoxyphenyl structure and the aromatic ring merged to pyridinone scaffold are useful to enhance the BRD9 binding affinity. These findings should guide the rational design of more prospective inhibitors targeting BRD9.Communicated by Ramaswamy H. Sarma

In this paper, we try to solve 3D offline packing optimization problem by combining two methods-genetic algorithm’ global performance and simulated annealing algorithm’ local performance. Given Heuristic rules in loading conditions, we use the optimal preservation strategy and the roulette wheel method to choose selection operator, integrating simulated annealing algorithm into genetic algorithm , and achieving code programming and algorithms by Matlab.This paper carries out an actual loading in a vehicle company in Changchun City, then makes a contrast between the final optimization results and each suppliers’ current packing data.The experimental results show that the algorithm has a certain validity and practicability in multiple container packing problem.

Our previous studies showed that biomodification of demineralized dentin collagen with proanthocyanidin (PA) for a clinically practical duration improves the mechanical properties of the dentin matrix and the immediate resin–dentin bond strength. The present study sought to evaluate the ability of PA biomodification to reduce collagenase-induced biodegradation of demineralized dentin matrix and dentin/adhesive interfaces in a clinically relevant manner. The effects of collagenolytic and gelatinolytic activity on PA-biomodified demineralized dentin matrix were analysed by hydroxyproline assay and gelatin zymography. Then, resin-/dentin-bonded specimens were prepared and challenged with bacterial collagenases. Dentin treated with 2% chlorhexidine and untreated dentin were used as a positive and negative control, respectively. Collagen biodegradation, the microtensile bond strengths of bonded specimens and the micromorphologies of the fractured interfaces were assessed. The results revealed that both collagenolytic and gelatinolytic activity on demineralized dentin were notably inhibited in the PA-biomodified groups, irrespective of PA concentration and biomodification duration. When challenged with exogenous collagenases, PA-biomodified bonded specimens exhibited significantly less biodegradation and maintained higher bond strengths than the untreated control. These results suggest that PA biomodification was effective at inhibiting proteolytic activity on demineralized dentin matrix and at stabilizing the adhesive/dentin interface against enzymatic degradation, is a new concept that has the potential to improve bonding durability.

Mechanical properties of extruded Mg-Zn-Nd-Y-Zr alloy are investigated by tensile tests at various temperatures range from room temperature to 350°C with strain rates of 6.0×10-4-6.0×10-1 s-1. It is found that the peak decrease with increasing temperature and decreasing strain rate, while the elongation increases with increasing temperature and decreasing strain rate. When deformation temperature is over 250°C, superplasticity occurs. This is ascribed to grain boundary sliding accommodated cavities growth. . At low temperature, the peak stress are a relatively higher than that of ZK60 alloy. This is explained by the grain refining effect and the precipitates of Mg9Nd and Mg6Zn3Y2.