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For understanding the influence of Nb element nanocomposite doping on the structure, mechanical and tribological properties of VN films, vanadium nitride(VN) and vanadium niobium nitride(VNbN) films were prepared using reactive magnetron sputtering method, and the microstructure, mechanical behavior and tribological behavior of the two films were compared and analyzed by field emission scanning electron microscopy(FESEM), atomic force microscope(AFM), EDS, XRD, microhardness tester, nanoindenter, friction testing machine, optical microscope and step profiler. Result showed that the doping of Nb element with an atomic fraction of 10.3% led to a higher density of the columnar crystal structure of VNbN thin films, and the surface roughness declined by 45.26%. The nanoindentation results indicated that the hardness of VNbN film was 20.47 GPa, which was 7.51% higher than that of VN film, and the H/E and H3/E2 values were also 18.64% and 49.25% higher than those of VN film, respectively. Tribological analysis revealed that the addition of Nb significantly improved the tribological properties of VNbN thin films at normal atmospheric temperature, with a friction coefficient as low as 0.35 and a wear rate as low as 3.30 × 10-6 mm3/(N·m). Moreover, the friction coefficient of VNbN film at high temperatures of 400 ℃ and 600 ℃ was as low as 0.58, which was also lower than that of VN films. However, its wear resistance significantly decreased at high temperatures, which was due to that the addition of Nb did not improve the oxidation resistance of VN film at high temperatures, the hardness of VNbN thin films deteriorated faster compared to VN film at high temperatures, the load bearing capacity during the rubbing was lower, and the film was easier to fall off.

In order to clarify the influencing rule of Ag content on the structure, tribological and anti - corrosion properties of CrN - Ag nanocomposite film, CrN film and Ag - doped CrN nanocomposite film were prepared by multi - target reactive magnetron sputtering technology. The microstructure, tribological behavior and corrosion behavior of the two films were characterized by scanning electron microscopy combined with energy dispersive spectroscopy (SEM - EDS), X - ray diffractometer (XRD), sphere - disc friction testing machine and electrochemical workstation. Results showed that a small amount of Ag (9.19%, atom fraction, the same below) could improve the density of CrN - Ag nanocomposite film, while excessive Ag (29.58%) would result in a loose film structure and the enrichment of Ag particles on the surface. The friction coefficient of the composite films decreased with the increase of Ag content, and the friction coefficient of the film with high Ag content (29.58%) was as low as 0.4 when the friction time was within 100 s, while the wear rate decreased first and then increased with the increase of Ag content. The wear rate of CrN - Ag(L) composite film was as low as 2.25×10-6 mm3/(N·m), which was 64.9% lower than that of the Ag - free CrN film. Electrochemical analysis showed that low Ag content had a positive effect on the corrosion resistance of CrN - Ag(L) film, while the excess Ag content significantly decreased the corrosion resistance of CrN - Ag(H) film.

Polytetrafluoroethylene (PTFE) solid self‐lubricating materials exhibit inferior tribological properties in the gamma‐irradiated environment. In this paper, amorphous hydrogen‐free carbon (a‐C) film was deposited on the PTFE polymer surface by magnetron sputtering, and the a‐C/PTFE samples were irradiated with gamma ray at a maximum dose of up to 5 MGy. The evolution of the structure and nanomechanical and tribological properties of a‐C/PTFE with different irradiation doses were investigated. The structural analyses reveal that the microstructure of a‐C films irradiated at 5 MGy doses is stable. Due to the covering of the a‐C film, significant cracks appear at the surface of the a‐C/PTFE sample only when the irradiation dose reaches 5 MGy. Before and after irradiation, the nanohardness and Young's modulus of the a‐C/PTFE are significantly higher than those of PTFE. The mechanical properties of PTFE are improved by a‐C film surface treatment. The friction experiments show that the average friction coefficients of both a‐C/PTFE and PTFE remain stable around 0.175 with increasing irradiation dose. When the irradiation dose is within 1 MGy, frictional behaviors occur only on the surface of a‐C films, and the wear rate of a‐C/PTFE is as low as 9.3 × 10−5 mm3/N.m, which is significantly lower than that of PTFE. The method of a‐C film treatment on the PTFE surface can dramatically improve the irradiation resistance of PTFE. [ABSTRACT FROM AUTHOR]

Autophagy controls insect development and can be targeted for pest control in agriculture. In the present study, starvation‐induced autophagy is investigated in the insect species Spodoptera frugiperda. Bioinformatics analysis and a search of the EST database (http://bioweb.ensam.inra.fr/spodobase) identifies a putative ATG8 gene of S. frugiperda. To generate a biomarker of autophagosome, the DNA sequence encoding the open reading frame of this gene is amplified and cloned into a pIEX‐4‐mCherry‐EGFP‐SfATG8 recombinant vector. Sf9 cells are then transfected with this expression vector and starved in phosphate‐buffered saline solution for 4 h to induce autophagy, which is examined by LysoTracker staining (Life Technologies, Grand Island, New York), western blotting and fluorescence microscopy. The results obtained show that starvation stimulates lipidation of SfATG8‐PE and the formation of autophagosomes, providing a foundation for further research with respect to autophagy in insects. [ABSTRACT FROM AUTHOR]

Objectives: This study assessed the efficacy, safety, pharmacokinetics (PK), and immunogenicity profiles of a denosumab biosimilar (LY06006) in Chinese postmenopausal osteoporotic women with a high risk of fracture., Methods: In this multicenter, randomized, double-blind, placebo-controlled, phase 3 trial, 448 postmenopausal women aged 50-85 years with osteoporosis were enrolled at 49 centers in China and were randomly assigned (3:1) to receive 60 ​mg of the denosumab biosimilar (LY06006) or placebo subcutaneously every 6 months for 1 year. Lumbar spine bone mineral density (BMD) change was the primary endpoint., Results: Of the 448 randomized patients, 409 (LY06006, n ​= ​311; placebo, n ​= ​98) completed the study. All 448 (100.0%) subjects were included in the intent-to-treat (ITT) trial, 427 (95.3%) were included in the full analysis set (FAS), 408 (91.1%) were included in the per protocol set (PPS), 446 (99.6%) were included in the safety set (SS), and 336 (75.0%) were included in the pharmacokinetics concentration set (PKCs). For the primary endpoint, a 4.71% (95% CI, 3.81%, 5.60%) treatment difference in percent change in lumbar spine BMD from baseline to month 12 was observed in the LY06006 group compared with the placebo group (P ​< ​0.0001). For the secondary endpoints, LY06006 was associated with increased lumbar spine BMD levels measured at month 6, BMD levels at the femoral neck, total hip, and trochanter measured at months 6 and 12 and reduced serum C-terminal telopeptide of type 1 collagen (CTX) and procollagen type 1 ​N-peptide (P1NP) levels at months 1, 6, and 12. Safety analysis was based on the safety analysis set (SS), and 264 (78.6%) subjects in the LY06006 group and 83 (75.5%) in the placebo group experienced adverse events (AEs). Most events were mild or moderate and not related to the study drugs., Conclusion: In postmenopausal women with a high risk of fracture, LY06006 increased the BMD and decreased bone resorption; thus, LY06006 might be an effective treatment for osteoporosis. LY06006 was generally safe and well tolerated without unexpected adverse reactions, similar to the reference drug Prolia®. The characteristics of effectiveness and safety were similar to those reported in previous studies., The Translational Potential of This Article: In this multi-center, randomized, double-blind, placebo-controlled phase 3 study, LY06006 showed substantially efficacy to increase BMD and well tolerance without unexpected adverse reactions, which is comparable to the reference drug Prolia ®. The presented results are encouraging and can offer some valuable evidence for the clinical practice., (© 2022 The Author(s).)