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Structural morphology, defects, compressibility and permeability properties studied by finite element analysis, selective laser melting technology and micromorphology, mainly to analyze the effect of porosity on the performance of porous skeletal scaffolds. The results showed that during the preparation process, there are construction errors. The designed structures were able to meet the requirements of cancellous and cortical bone in terms of compressive stress and elastic modulus. The compressive stresses of the diagonal cubic compact row and octahedron are more similar at the same porosity, the elastic modulus and compressive stress decrease with increasing porosity for three structures. In the hydrodynamic analysis, the maximum flow velocity appears in octahedron up to 0.001m/s. Permeability increases with increasing porosity for all structures. The maximum permeability was obtained at 75% porosity for all structures, the pressure drop for three structures at this porosity was most similar to that of natural bone (4.153 E3 N/m3).

Background: The course of organ dysfunction (OD) in Corona Virus Disease 2019 (COVID-19) patients is unknown. Herein, we analyze the temporal patterns of OD in intensive care unit-admitted COVID-19 patients. Methods: Sequential organ failure assessment scores were evaluated daily within 2 weeks of admission to determine the temporal trajectory of OD using group-based multitrajectory modeling (GBMTM). Results: A total of 392 patients were enrolled with a 28-day mortality rate of 53.6%. GBMTM identified four distinct trajectories. Group 1 (mild OD, n = 64), with a median APACHE II score of 13 (IQR 9-21), had an early resolution of OD and a low mortality rate. Group 2 (moderate OD, n = 140), with a median APACHE II score of 18 (IQR 13-22), had a 28-day mortality rate of 30.0%. Group 3 (severe OD, n = 117), with a median APACHR II score of 20 (IQR 13-27), had a deterioration trend of respiratory dysfunction and a 28-day mortality rate of 69.2%. Group 4 (extremely severe OD, n = 71), with a median APACHE II score of 20 (IQR 17-27), had a significant and sustained OD affecting all organ systems and a 28-day mortality rate of 97.2%. Conclusions: Four distinct trajectories of OD were identified, and respiratory dysfunction trajectory could predict nonpulmonary OD trajectories and patient prognosis.

Abstract Background Rapeseed cake is an important agricultural waste. After enzymatic fermentation, rapeseed cake not only has specific microbial diversity but also contains a lot of fatty acids, organic acids, amino acids and their derivatives, which has potential value as a high-quality organic fertilizer. However, the effects of fermented rapeseed cake on tea rhizosphere microorganisms and soil metabolites have not been reported. In this study, we aimed to elucidate the effect of enzymatic rapeseed cake fertilizer on the soil of tea tree, and to reveal the correlation between rhizosphere soil microorganisms and nutrients/metabolites. Results The results showed that: (1) The application of enzymatic rapeseed cake increased the contents of soil organic matter (OM), total nitrogen (TN), total phosphorus (TP), available nitrogen (AN), and available phosphorus (AP); increased the activities of soil urease (S-UE), soil catalase (S-CAT), soil acid phosphatase (S-ACP) and soil sucrase (S-SC); (2) The application of enzymatic rapeseed cake increased the relative abundance of beneficial rhizosphere microorganisms such as Chaetomium, Inocybe, Pseudoxanthomonas, Pseudomonas, Sphingomonas, and Stenotrophomonas; (3) The application of enzymatic rapeseed cake increased the contents of sugar, organic acid, and fatty acid in soil, and the key metabolic pathways were concentrated in sugar and fatty acid metabolisms; (4) The application of enzymatic rapeseed cake promoted the metabolism of sugar, organic acid, and fatty acid in soil by key rhizosphere microorganisms; enzymes and microorganisms jointly regulated the metabolic pathways of sugar and fatty acids in soil. Conclusions Enzymatic rapeseed cake fertilizer improved the nutrient status and microbial structure of tea rhizosphere soil, which was beneficial for enhancing soil productivity in tea plantations. These findings provide new insights into the use of enzymatic rapeseed cake as an efficient organic fertilizer and expand its potential for application in tea plantations.

Nano-surface layers were prepared on the surface of 6061 aluminum alloy using the ultrasonic surface rolling process (USRP). The surface morphology, surface roughness, microstructure, hardness, and corrosion resistance of 6061 aluminum alloy were systematically characterized using X-ray diffraction (XRD), laser scanning confocal microscopy (LSCM), optical microscope(OM), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), and other testing methods. The results showed that ultrasonic surface rolling strengthening did not change the surface phase composition of 6061 aluminum alloy. It changed the size of the surface phases and the distance between the phases while refining the surface grains. The static pressures has a great influence on the surface properties of 6061 aluminum alloy. The best surface properties were obtained under 500N static pressures. The surface hardness reached 129.5HV0.5, the surface morphology was flat and continuous, the surface roughness was reduced to Ra0.191μm, and the corrosion resistance was significantly improved.

316L porous skeletal scaffolds prepared by selective laser melting (SLM) technology are currently widely used in bone injuries. Its successful implantation is predicated on having properties that match those of natural bone. The process parameters significantly influence the performance of SLM-316L porous scaffold. In this study, the nine-group shaping process parameters were determined by orthogonal method. The 316L porous scaffolds were tested in compression, electrochemistry, XRD and microstructure. The influence of process parameters on the performance of body-centered cubic peripheral square structure bracket was investigated. The influence laws of process parameters on microstructure, mechanical properties and corrosion resistance were obtained. The results show that process parameters have a significant effect on the microstructure, properties and defect distribution. The reduction of defects and grain refinement in the stent is conducive to the improvement of compressive properties and hardness of the stent. The magnitude of the hardness is inversely related to the grain size. The corrosion current density of porous scaffolds are also affected by their microscopic defects and grain size. At an energy density of 78.70 J mm ^−3 presents the least defects and obtains smaller grains, resulting in the best mechanical properties and corrosion resistance.