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The NiCr/YSZ coating was fabricated on γ-TiAl alloy by double glow plasma surface metallurgy technology and multi-arc ion plating technology. The microstructure, microhardness, bonding strength, and burn resistance of NiCr/YSZ coating were studied in detail. The results showed that the NiCr/YSZ coating was dense and homogeneous, including a duplex structure of top YSZ ceramic coating and underlying Ni-Cr bond coating. The average microhardness of NiCr/YSZ coating was raised by a factor of about 2 compared to the γ-TiAl substrate. The thermal shock test indicated that the composite structure had superior bonding strength and the defects such as metal droplets on the ceramic coating were the source of cracks. The high-energy laser beam destroyed the surface of γ-TiAl alloy, forming protruding combustion products in ablation zone and splashing residues around ablation zone. When coated by NiCr/YSZ coating, the combustion process was delayed through isolating and dissipating heat. The ablation range was controlled and the ablation damage was reduced at the same irradiation power. The NiCr/YSZ coating preliminarily realized to improve the burn resistance of γ- TiAl alloy.

To improve the wear resistance of γ-TiAl alloy, Ta alloy layer was prepared on surface by double glow plasma surface alloying technique. The tribology behavior of Ta alloy layer against Si3N4 at 25℃, 350℃ and 500℃ were comparatively studied. The results showed that Ta alloy layer comprised a deposition layer and a diffusion layer. The deposition layer played a role in protection as a soft film. With the increase of temperature, the wear mechanism of γ-TiAl changed from abrasive wear to coexistence of abrasive wear and oxidation wear. Ta alloy layer’s wear mechanism changed from adhesive wear to coexistence of adhesive wear and oxidation wear. Surface Ta alloying process significantly reduced the wear volume, the specific wear rate and the friction coefficient of γ-TiAl and improved the wear resistance properties of γ-TiAl.

In the present paper, plasma surface alloying was implemented on powder metallurgy gears to improve its wear resistance based on double glow plasma surface metallurgy technology. A W-Mo alloy coating was obtained in the process. The morphology, microstructure and phase composition were investigated by SEM, EDS and XRD. The hardness was examined by Vickers hardness test and nanoindentation test. The tribological behavior of powder metallurgy gears before and after plasma surface alloying was evaluated on a ball-on-disc reciprocating sliding tribometer under dry sliding condition at room temperature. The results indicate that the W-Mo alloy coating is homogeneous without defects, which includes deposition layer and interdiffusion layer. The average microhardness of powder metallurgy gears before and after plasma surface alloying is 145.8 HV0.1 and 344.4 HV0.1, respectively; Nano hardness of deposition layer and interdiffusion layer is 5.76 GPa, 14.35 GPa, respectively. The specific wear rate of W-Mo alloy coating is lower than original PM gears. The wear mechanism of W-Mo alloy coating is slight adhesive wear. The W-Mo alloy coating prepared by double glow plasma surface alloying technology can effectively improve wear resistance of powder metallurgy gears.

Objective: To summarize and analyze the clinical features, treatment, and prognosis of pulmonary artery stenosis post-lung transplantation. Methods: A 62-year-old male patient was admitted to the hospital with a cough and chest tightness of over a year's duration, which had worsened in the last two months, leading to the diagnosis of idiopathic pulmonary fibrosis. The clinical data were observed and reviewed post-left allograft single lung transplantation. Literature searches were conducted using the keywords "lung transplantation" "stenosis, pulmonary artery" and "postoperative complications" in CNKI, Wanfang Medical Network, and PubMed databases up to December 2022. Results: On January 26, 2022, a left allograft single lung transplantation was performed under general anesthesia. Postoperatively, extracorporeal membrane oxygenation and mechanical ventilation were successfully weaned off at 22 hours and 2 days, respectively, with transfer from the intensive care unit 12 days after surgery. PaO 2 and PaCO 2 were 50 mmHg and 40 mmHg after deoxygenation. Both pulmonary CT angiography and ventilatory-perfusion imaging indicated stenosis of the left pulmonary anastomosis. Balloon dilation and pulmonary artery stenting were performed, with PaO 2 and PaCO 2 improving to 87 mmHg and 42 mmHg, respectively. The patient was discharged 102 days post-surgery, and was followed up for 1 year, with a good prognosis. Additionally, 36 related articles were retrieved, encompassing 69 cases with a median age of 53 years (38.5-59.0 years). Of these, 27.54% (19/69) were diagnosed with idiopathic pulmonary fibrosis, 46.38% (32/69) underwent single lung transplantation, with the primary clinical symptom being hypoxemia in 71.01% (49/69) cases. Left pulmonary artery anastomotic stenosis was observed in 43.48% (30/69), with 65.22% (45/69) being diagnosed in the late postoperative period. Interventional therapy was performed to 44.93% (31/69), with a mortality rate of 21.74% (15/69). Conclusions: The primary clinical manifestation of post-lung transplantation pulmonary artery stenosis is hypoxemia and can be diagnosed by pulmonary artery CT angiography, transesophageal echocardiography, and pulmonary angiography. Early diagnosis can significantly reduce mortality, and interventional therapy is an effective treatment for severe pulmonary artery stenosis post-lung transplantation.

Prey animals modify their behaviour and physiology in the presence of predators. Domestic animals differ from wild animals in having less exposure to wild predators, but whether they still retain an antipredator instinct is frequently unknown. In this study, we used domesticated Small Tail Han sheep as a model prey animal to gauge their response to the presence of predators, in the form of odours from the faeces of lion, tiger, and leopard. The faeces of male sheep and male rabbit (as a heterogeneous non-predator) were used as control. We found that the frequency and time of feeding, exploration, moving, watching, and lying down behaviours were significantly affected by predator odour, and that there was an interaction between odour sources and sex. When exposed to predator odour, sheep reduced their frequency and time of feeding, and increased their exploratory, moving, and watching behaviours. Female sheep showed greater motivation towards frequent and lengthy exploration, moving, watching, and lying down behaviours than male sheep, and less motivation towards feeding and drinking behaviours. Serum cortisol levels were lowest in response to tiger stimuli. These results illustrated that Small Tail Han sheep could recognise predator odour and adjust their behaviour to display antipredator strategies, and displayed some physiological responses, although only changing in serum cortisol could be significantly attributed to the odour of predators., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Objective: To observe the efficacy of lung transplantation for pulmonary alveolar proteinosis (PAP) patients and to improve the understanding of the therapy. Methods: The clinical data of a patient with autoimmune PAP treated with sequential homogenous bilateral lung transplantation were described and the literatures were reviewed. Results: This 55-year-old female patient was diagnosed with autoimmune PAP and had been treated with whole lung lavage for 19 times, but only achieved short-term symptomatic relief after each operation. Inhalation of granulocyte macrophage colony stimulating factor occurred allergic reactions. Lung transplantation was performed on February 15, 2022, and a significant improvement in oxygenation and clinical symptoms were observed. The patient remained stable during follow-up. Conclusion: Treatment with lung transplantation is safe and effective for end-stage patients with PAP in the early phase, but the long-term effect remains to be observed.

The mechanism of dominant follicle selection is unclear because of its physiological complexity. However, some studies have reported that the immune system plays an important role in reproductive physiology. The objective of the current study was to investigate the differential expression of Toll-like receptors (TLRs) in the dominant (DFs) and nondominant follicles (NFs), and to determine the correlation between the expression of TLRs and the related genes, such as WNT4 and FOXL2. In this comparative study, the expression levels of TLRs, WNT4, and FOXL2 genes of DFs and NFs were obtained from three Dazu black goats were estimated using the real-time PCR. Our results showed no significant difference in the expression of seven TLRs (excluding TLR2, TLR5, and TLR8), WNT4, and FOXL2 between the DFs and NFs. In addition, the mRNA expression levels of WNT4 significantly correlated with the relative expression of TLR6 (r = 0.949739, P < 0.01); however, no significant expression of the TLR genes was found to be associated with FOXL2 mRNA expression. Our results support the fact that TLRs are not involved in the process of dominant follicle selection; however, TLR6 might play a role in the development of follicles by interacting with WNT4.