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Abstract Background Laparoscopic radical resection of gastrointestinal cancer is associated with a high incidence of postoperative catheter-related bladder discomfort (CRBD). Studies on the benefits of magnesium sulfate intravenous infusion during the perioperative period post-laparoscopic surgery are yet lacking. Methods A total of 88 gastrointestinal cancer male patients scheduled for laparoscopic radical resection were randomly divided into two groups: normal saline (control) and magnesium. In the magnesium group, a 40 mg/kg loading dose of intravenous magnesium sulfate was administered for 10 min just after the induction of anesthesia, followed by continuous intravenous infusion of 15 mg/kg/h magnesium sulfate until the end of the surgery; the control group was administered the same dose of normal saline. Subsequently, 2 μg/kg sufentanil was continuously infused intravenously by a postoperative patient-controlled intravenous analgesia (PCIA) device. The primary outcome was the incidence of CRBD at 0 h after the surgery. The secondary outcomes included incidence of CRBD at 1, 2, and 6 h postsurgery, the severity of CRBD at 0, 1, 2, and 6 h postsurgery. Remifentanil requirement during surgery, sufentanil requirement within 24 h postsurgery, the postoperative numerical rating scale (NRS) score at 48 h after the surgery, magnesium-related side effects and rescue medication (morphine) requirement were also assessed. Results The incidence of CRBD at 0, 1, 2, and 6 h postoperatively was lower in the magnesium group than the control group (0 h: P = 0.01; 1 h: P = 0.003; 2 h: P = 0.001; 6 h: P = 0.006). The incidence of moderate to severe CRBD was higher in the control group at postoperative 0 and 1 h (0 h: P = 0.002; 1 h: P = 0.028), remifentanil requirement during surgery were significantly lower in the magnesium group than the control group. Sufentanil requirements during the 24 h postoperative period were significantly lower in the magnesium group than the control group. The NRS score was reduced in the magnesium group compared to the control group in the early postoperative period. Magnesium-related side effects and rescue medication (morphine) did not differ significantly between the two groups. Conclusions Intravenous magnesium sulfate administration reduces the incidence and severity of CRBD and remifentanil requirement in male patients undergoing radical resection of gastrointestinal cancer. Also, no significant side effects were observed. Trial registration Chictr.org.cn ChiCTR2100053073. The study was registered on 10/11/2021.

Nanocrystalline metals have many applications in nanodevices, especially nanoscale electronics in aerospace. Their ability to resist fracture under impact produced by environmental stress is the main concern of nanodevice design. By carrying out molecular dynamics simulations under different fast loading rates, this work examines the effect of impact load on the fracture behavior of nanocrystalline bcc iron at an atomistic scale. The results show that a crack propagates with intergranular decohesion in nanocrystalline iron. With the increase in impact load, intergranular decohesion weakens, and plastic behaviors are generated by grain boundary activities. Also, the mechanism dominating plastic deformation changes from the atomic slip at the crack tip to obvious grain boundary activities. The grain boundary activities produced by the increase in impact load lead to an increase in the threshold energy for crack cleavage and enhance nanocrystalline bcc iron resistance to fracture. Nanocrystalline bcc iron can keep a high fracture ductility under a large impact load.

Here we advocate the strategic design of dispersed heterostructure to retain ductility and toughness in high-strength metals, using the equiatomic CrCoNi alloy as an example. Dispersed heterostructure, with nanograins and/or ultrafine grains (the hard zone) dispersed around micrometer-sized grain (the soft zone), is fabricated by cold-rolling followed by sequential flash-annealing at increasing temperatures. It displays a decent uniform elongation of ∼ 20 % and an exceptional strain energy density limit up to ∼ 240 mJ/mm3 at the strength level of ∼ 1.2 GPa, which is unattainable by its homogeneous as well as clustered heterogeneous counterparts. Grain size-dependent heterogeneous deformation evokes inter-zone interactions, which induce strain partitioning, activate additional mechanical twinning and promote developments of dislocation gradient and long-range internal stress near zone boundary sequentially, imparting a multistage work hardening with extraordinary strain hardening rate up-turn followed by slow attenuation. Dispersed heterostructure provides a higher density of zone boundary, ensuring more extensive inter-zone interaction and thus maximizing the extraordinary strain hardening to improve ductility.

Grain boundary structures with high resistance to intergranular fracture are the target of grain boundary design. In this work, grain boundary elimination in front of crack tip is observed in two special bcc iron bicrystals through molecular dynamics simulations under mode I loading. Grain boundary elimination depends on crack advance direction and enhances resistance to intergranular fracture. Direction-dependent elimination leads to directional anisotropy of intergranular crack propagation. By analytical analysis and molecular dynamics simulation, grain boundary elimination is found to be attributed to the activities of twinning and dislocation. All twinning bands are formed by atomic slip along ordinary twinning direction, but all dislocations are nucleated by atomic slip along anti-twinning direction. Mechanisms of twinning formation and dislocation nucleation are revealed by calculating energy barriers of atomic slip and shear stress field. According to the mechanism of grain boundary elimination, conditions for grain boundary elimination are proposed to find all special grain boundaries. Results show that twist grain boundaries cannot be eliminated under mode I loading, while tilt grain boundaries with axes of 〈110〉 can. This work provides a good reference for grain boundary design.

Video Compressive Sensing (VCS) works to recover the scene video from limited compressed measurements. VCS was intended to sense and recover the scene video in spatial-temporal sensing manner. It is difficult to be performed due to the complexity of design and optimization. The most current approaches measure the scene video only in the spatial or temporal domain. However, this would lose the spatial-temporal correlation in VCS. Focus on this issue, this paper proposes a VCS framework, which uses the learned spatial-temporal sensing manner and the hybrid-3D recovery network. In terms of technical study, we develop a hybrid-3D residual block consisting of Pseudo-3D and True-3D sub-blocks. This structure enables the network to intuitively represent the spatial-temporal feature, and significantly reduces the network parameters. In the detailed design, we explore the optimal hybrid-3D blocks. Experimentally, we validate the effectiveness of the learned spatial-temporal sensing manner. In addition, experimental results show that the proposed method achieves state-of-the-art performance on video sequences belonging to Vid 4 and SPMCS dataset, while the recovery speed is ultra-fast.

Electro-mechanical transmission is the best choice for the transmission system of military, engineering and other heavy special vehicles. The scheme design is fundamental and key to realize the original innovation of the electro-mechanical transmission. Therefore, a novel design method of a planetary-gear scheme is proposed for electro-mechanical transmission. According to the distribution of mechanical points and the speed continuous condition of mode switching, the mode combination law of a dual-mode electro-mechanical transmission is obtained, i.e., the input split mode based on the scheme of three-degree-of-freedom (3-DOF) and the compound split mode based on the scheme of 2-DOF. Moreover, a design method for an electro-mechanical transmission scheme is proposed based on the mode combination law. Two single-mode schemes are combined to form a dual-mode scheme, and then mode jointing, control logic, isomorphism and other screening conditions are in turn used to screen schemes; therefore, two optimized schemes are obtained ultimately. Lastly, by analyzing the characteristics of speed, torque and the power split of the optimized schemes, the accuracy of the proposed design method in this paper is verified. The proposed design method can provide new ideas of designing multi-mode and multi-output electro-mechanical transmission schemes.

Immediately following the discovery of tryptophan hydroxylase in Drosophila, we demonstrated the presence of tryptophan hydroxylase in the brain of the beetle Harmonia axyridis (Coleoptera: Coccinellidae). However, whether tryptophan hydroxylase is present in the brains of other insects is still a matter of discussion. In the current study, sheep anti-tryptophan hydroxylase polyclonal antibody has been applied to test for tryptophan hydroxylase immunoreactivity in a broader taxonomic range of insect brains, including holometabolous and hemimetabolous insects: one species each of Coleoptera, Hymenoptera, Diptera, and Blattaria, and two species of Lepidoptera. All species show consistent tryptophan hydroxylase immunoreactivity with distribution patterns matching that of serotonin. The immuno-positive results of such an antibody in brains from diverse orders of insects suggest that specific tryptophan hydroxylase responsible for central serotonin synthesis is probably present in the brains of all insects. [ABSTRACT FROM AUTHOR]