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Partially-etched V2Al1-xCTz ceramic with the average particle of ∼400 nm was synthesized by etching submicro-sized V2AlC with 40 wt% HF at room temperature (RT) for 48 h and 72 h, respectively. V2Al1-xCTz etched for 72 h has exhibited higher charge-discharge property, with an average reversible discharge capacity of 349.2 mAh·g-1 at 0.1 A g-1 in the 120 cycles for lithium-ion batteries. The electrochemical performances of V2Al1-xCTz could be improved by the addition of carbon nanotubes (CNTs), graphene (GF) and titanium suboxides (Ti4O7) conductive additives, among which CNTs exhibit the best effectiveness with a capacity of ∼460 mAh·g-1 at 0.1 A g-1 in the 140 cycles and a capacity retention of ∼72% at 0.5 A g-1 after 400 cycles.

High-purity and fine CrB powders are firstly synthesized from Cr and B powders in (Na, K)Cl molten salt at 850 °C for 2 h. Then the as-achieved CrB powders are used as precursors to synthesize homogeneous and size-controlled Cr2AlB2 powders in (Na, K)Cl molten salt at 900 °C for 2 h. Additionally, the formation mechanisms of CrB and Cr2AlB2 in (Na, K)Cl molten salt are also investigated. Results show that the Cr atom, formed by disproportionation of Cr2+ ions in molten salt, reacts in-situ with B powders to form CrB. For the formation of Cr2AlB2, Al and CrB migrate mutually and assemble firstly in the molten salt, and then Al intercalates into CrB to generate Cr2AlB2.

The corrosion of metallic bipolar plates in the proton exchange membrane fuel cells (PEMFCs) anode environment would degrade the performance and shorten the lifespan of the fuel cell. Hence, it is essential to develop a conductive coating with good corrosion resistance. Herein we demonstrate a dense, defect-free, and well-adhered nanocrystalline β-Nb2N coating prepared on 430 ferritic stainless steel (430 FSS) via disproportionation of Nb(Ⅳ) species in molten salts. The corrosion mechanism of bare and β-Nb2N coated 430 FSS in the simulated PEMFC anode environment is also studied by electrochemical techniques including potentiodynamic polarization, potentiostatic polarization, and electrochemical impedance spectroscopy. Results show that β-Nb2N coating can significantly improve the corrosion resistance of the steel alloy with acceptable contact resistance. In addition, no obvious degradation is observed for the β-Nb2N coating after potentiostatic polarization measurement for 500 h. This work offers a promising strategy to develop the corrosion protective coating on metallic bipolar plates for PEMFCs.

Herein we report a method for rapid synthesis of Cr2AlB2 from Cr, Al, and B elemental powders. Effects of Cr/Al/B molar ratio in precursors, temperature, duration and mass ratio of the salt to precursors on Cr2AlB2 formation are investigated. Additionally, the synthesis process of Cr2AlB2 is also discussed. Results show that the temperature plays a key role in the formation of Cr2AlB2. Well crystalline Cr2AlB2 powders are successfully synthesized from 2Cr/2Al/2B precursors and NaCl-KCl molten salt with their mass ratio of 1:1 at 1100 °C within 0.5 h. Cr2AlB2 exhibits nanolaminated structure with plate-like grain morphology. The particle size of the obtained Cr2AlB2 powder is dramatically decreased with the addition of NaCl-KCl molten salt in precursors.

Cell aging is an extremely complex process, which is characterized by mitochondrial structural dysfunction, telomere shortening, inflammatory microenvironment, protein homeostasis imbalance, epigenetic changes, abnormal DNA damage and repair, etc. Aging is usually accompanied by structural and functional damage of tissues and organs which further induces the occurrence and development of aging-related diseases. Aging includes physiological aging caused by increased age and pathological aging induced by a variety of factors. Noteworthy, as a target organ directly contacting with the outside air, lung is more prone to various stimuli, causing pathological premature aging which is lung aging. Studies have found that there is a certain proportion of senescent cells in the lungs of most chronic respiratory diseases. However, the underlying mechanism by which these senescent cells induce lung senescence and their role in chronic respiratory diseases is still obscure. This paper focuses on the causes and classification of lung aging, the internal mechanism of lung aging involved in chronic respiratory diseases, and the application of anti-aging treatments in chronic respiratory diseases. We hope to provide new research ideas and theoretical basis for the clinical prevention and treatment in chronic respiratory diseases.

With the increasing use of antibiotics, their ecological impacts have received widespread attention. However, research on the toxicity of quinolone antibiotics is still limited, especially regarding the oxidative stress and phyllosphere of plants. In this study, the toxic effects of enrofloxacin, norfloxacin, and levofloxacin on Arabidopsis thaliana and their underlying mechanisms were investigated. The toxicity of the three quinolone antibiotics decreased in the following order: enrofloxacinnorfloxacinlevofloxacin. Physiological cellular changes, such as plasmolysis and chloroplast swelling, were observed using electron microscopy. Photosynthetic efficiency was inhibited with a decline in the effective photochemical quantum yield of photosystem II (Y(II)) and non-photochemical quenching (NPQ), indicating that quinolone antibiotics might reduce light energy conversion efficiency and excess light energy dissipation. Oxidative stress occurred in A. thaliana after quinolone antibiotic treatment, with an increase in reactive oxygen species (ROS) levels and malondialdehyde (MDA) content. High ROS levels stimulated the over-expression of superoxide-responsive genes for self-protection. Structural equation modeling (SEM) analysis showed that photosynthesis inhibition and cellular damage caused by oxidative stress were critical factors for growth inhibition, suggesting that the antioxidant response activated by ROS might be a potential mechanism. Furthermore, the diversity of the phyllospheric microbial communities decreased after enrofloxacin exposure. Additionally, specific microbes were preferentially recruited to the phyllosphere because of the higher ROS levels.

Background: Neonatal respiratory system disease is closely associated with embryonic lung development. Our group found that Integrin β4(ITGB4) is downregulated in the airway epithelium of asthma patients. Asthma is the most common chronic respiratory illness in childhood. Therefore, we suspect whether the deletion of ITGB4 would affect fetal lung development? In this study, we characterized the role of ITGB4 deficiency in Bronchopulmonary dysplasia (BPD). Methods: ITGB4 was conditionally knocked out in CCSP-rtTA; Tet-O-Cre; ITGB4f/f triple transgenic mice administrating doxycycline from E7.5 to P42. Lung tissues at different developmental stages were collected for experimental detection and transcriptome sequencing. The expression of lung-development-relevant factors were evaluated by transcriptome sequencing, WB and Immunohistochemical. Bronchoalveolar lavage fluid were collected to perform Total cell and differential inflammatory cell counts. The effects of ITGB4 deficiency on lung branching morphogenesis were observed by fetal mouse lung explants culture. Results: We found that β4CCSP.Cre mice exhibit significant lighter body weight comparing to age-matched littermate control β4f/f, and the difference became more distinct as their age increase. ITGB4 deficiency shows no significant impact on the ratio of lung weight to body weight and the overall survival rates of mice. Deleting ITGB4 from the airway epithelial cells result in enlarged alveolar airspaces, inhibition of branching, the overlapping of epithelium cells and the impairment of cilial growth during lung development. Scanning electron microscopy showed that the airway epithelial cilia of β4CCSP.Cre group appear to be sparse, shortened, and lodging. Lung-development-relevant factors such as SPTPC、SOX2 significantly decreased in both mRNA and protein level. KEGG pathway analysis indicated that multiple ontogenesis-regulating-relevant pathway converge to FAK, accordingly, ITGB4 deletion decreased phospho-FAK, phospho-GSK3β, SOX2 level, and correspondingly contrary consequence was detected after treatment with GSK3β agonist（wortmannin）. Airway branching defect of β4CCSP.Cre mice lung explants was also partly recovered after wortmannin treatment. Conclusions: Airway epithelial-specific deletion of ITGB4 contributes to lung developmental defect, which could be achieved through the FAK/GSK3β/SOX2 signal pathway.

Lower respiratory tract infection (LRTI) induced by respiratory syncytial virus (RSV) is an important cause of hospitalization for infants. Compared with adults, infants are more likely to cause serious respiratory diseases after RSV infection due to the specific immature airway structure and immune system. The balance of immune resistance and immune tolerance of the host is critical to effective virus clearance and disease control. This paper reviews the relationship between RSV infection and respiratory diseases in infancy, the influence factors of the high pathogenicity of RSV infection in early life, as well as the research progress of anti-RSV therapy, and expands the specific molecular events regulating immune resistance and immune tolerance. We expect to present new ideas for the prevention and treatment of RSV-related respiratory diseases in clinical practice.

Dendrobium officinale Kimura et Migo (D. officinale) is a famous traditional Chinese medicine (TCM). A mixture of D. officinale and American ginseng has been shown to enhance cell-mediated immunity, humoral immunity, and monocyte/macrophage functions in mice. Here, the effects of a D. officinale and American ginseng mixture on the structure of gut microbial community in dogs were examined using high-throughput 16S rRNA gene amplicon sequencing. The data revealed that while the mixture did not change the diversity of gut microbial community significantly, differences among individuals were significantly reduced. Furthermore, the mixture-responsive operational taxonomic units (OTUs) exhibited a phase-dependent expression pattern. Fifty-five OTUs were found to exhibit a mixture-induced expression pattern, among which one third were short-chain fatty acid (SCFA)-producing genera and the others were probiotic genera included Lactobacillus spp., Sutterella, Alistipes, Anaerovorax, Bilophila, Coprococcus, Gordonibacter, Oscillibacter, among others. By contrast, 36% of the OTUs exhibiting a mixture-repressed expression pattern were disease-associated microorganisms, and six genera, namely Actinomyces, Escherichia/Shigella, Fusobacterium, Slackia, Streptococcus and Solobacterium, were associated with cancer. In addition, five genera were closely associated with diabetes, namely Collinsella, Rothia, Howardella, Slackia and Intestinibacter. Our results indicate that this D. officinale and American ginseng mixture may be used as a prebiotic agent to enhance SCFA-producing genera and prevent gut dysbiosis.

β-Nb2N, a transition metal nitride, has attracted significant interest due to its high hardness, high electrical conductivity, as well as its good corrosion and wear resistance. Herein, a simple novel method to prepare nanocrystalline β-Nb2N coating on 430 stainless steel substrate by disproportionation of Nb(IV) ions in molten salt is developed and presented. Through this method, a dense, crack-free, uniform, and well-adhered nanocrystalline β-Nb2N coating is obtained in NaCl–KCl–NaF–NbCl5–Nb melt at 850 °C for 5 h. Additionally, effects of temperature and duration on β-Nb2N coating formation are also investigated. Results indicate that higher temperature and longer duration are more favorable for β-Nb2N coating formation. Furthermore, the corrosion behavior of the coating was studied by potentiodynamic polarization in 3.5% NaCl solution. Result suggests that the β-Nb2N coating can significantly improve the pitting corrosion resistance of 430 FSS substrate.

Pure metastable tetragonal (t’) phase 4YSZ top coats with thickness of 100 and 200 μm were deposited on NiCoCrAlY-coated second generation single crystal superalloy by air plasma spray (APS). The two thermal barrier coatings were evaluated under gradient thermal cycling test using gas mixture of propane and oxygen. After flame shock test, the values of Young's modulus, hardness and degree of densification all exhibited a gradient distribution across YSZ thickness. In contrast to intensive sintering at surface of 200 μm 4YSZ coating, the TBC sample with 4YSZ layer of 100 μm underwent poor oxidation at interface of YSZ and bond coat, forming a duplex oxide scale: (Ni,Co)(Cr,Al)2O4 spinel over Al2O3, which promoted the delamination at the top-coat/bond-coat interface. The resistance against gradient thermal cycling, the phase stability of 4YSZ and the failure mechanism of the TBCs, were discussed correlating to the effects of YSZ thickness.

Herein we report, a simple novel method to synthesize nanosized Ti3AlC2 powder from Ti, Al, and C powders in NaCl–KCl molten salt. It is more conducive to the formation of Ti3AlC2 at higher salt/precursor materials ratio and particle size of Ti3AlC2 powder dramatically decreases with increasing mass ratio of the salt to precursor materials. Fine-grained Ti3AlC2 powder is successfully synthesized at 950○C for 5 h or at 1000○C for 2 h with a salt/precursor materials ratio of 10:1. Ti3C2 MXene is also prepared by etching fine-grained Ti3AlC2 precursor in HF solution at 60°C for 2 h.

Nanosized niobium carbide (NbC) powder was successfully synthesized by disproportionation reaction of Nb(IV) species in NaCl-KCl molten salt at 800–900 °C for 0.5–5 h by using a mixture of Nb, NbCl5, and acetylene black as raw materials. Effects of molar ratio of NbCl5/Nb, temperature, and reaction time on NbC preparation were also investigated. The composition and microstructure of the product were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and high resolution transmission electron microscopy (HRTEM). Homogenous NbC powder with a particle size of ~50 nm is in-situ synthesized on template of acetylene black by disproportionation reaction of Nb(IV) species in NaCl-KCl molten salt. In addition, NbC formation is dramatically influenced by molar ratio of NbCl5/Nb and temperature, a higher temperature and higher molar ratio of NbCl5/Nb are more preferable for nanosized NbC powder formation.

A rotating packed bed (RPB) is a new type of process intensification equipment. Its packing zone is an important mass transfer zone. However, the issue of liquid flow in the RPB remains unclear. In this work, the effects of rotational speed, liquid initial velocity in the cavity, and the packing zone of a countercurrent rotating bed on liquid phase flow patterns, droplet velocity, average droplet diameter, and droplet size distribution were measured using a charge-coupled device (CCD) camera in the air–water system. Experimental results show the influence of rotational speed and liquid initial velocity on fluid flow characteristics. Computational fluid dynamics modeling was employed to analyze the characteristics of liquid flow. Two-dimensional numerical simulation of gas–liquid two-phase flow was achieved using the volume of fluid model in the multiphase flow model and the Reynolds stress model in the turbulence model. Simulation results are consistent with the experimental rules. In addition, correlations were established to predict the average droplet diameter, the rotational speed, and the liquid initial velocity. The predicted values were in agreement with the experimental values, with deviations generally within ±15%.

A static hydrothermal approach was adopted to synthesize nanosized SiO2-ZSM-5 zeolite in the media of F−-OH− with double mineralizers, using tetraethoxysilane, sodium aluminate, and tetrapropylammonium hydroxide as the silicon source, aluminum source, and template agent, respectively. The physical and chemical properties of the synthesized ZSM-5 zeolites were characterized and their catalytic performance was evaluated in the conversion methanol to propene (MTP); the effect of F−/Al2O3 molar ratio on the catalytic performance of synthesized H-ZSM-5 was investigated. The results indicate that an increase in the F−/Al2O3 molar ratio of the synthesis mixture leads to an increase in the surface content of microcrystalline SiO2, accompanying with a decrease in the relative crystallinity, surface area, pore volume, and acid strength and density. With a F−/Al2O3 molar ratio of 12, the SiO2-ZSM-5 zeolite exhibits the best catalytic performance in MTP, with a selectivity of 45% to propene and a propene/ethene (P/E) ratio of greater than 10. It is further hypothesized that the transition state shape selectivity plays an important role in determining the product selectivity in MTP.

Objectives Our aim was to investigate the prevalence and predictive variables of sarcopenia. Methods We recruited participants from the Peking Union Medical College Hospital Multicenter Prospective Longitudinal Sarcopenia Study (PPLSS). Muscle mass was quantified using bioimpedance, and muscle function was quantified using grip strength and gait speed. Logistic regression revealed the relationships between sarcopenia and nutritional, lifestyle, disease, psychosocial and physical variables. Results The prevalence of sarcopenia and sarcopenic obesity was 9.2%‐16.2% and 0.26%‐9.1%, respectively. Old age, single status, undernourishment, higher income, smoking, low physical activity, poor appetite and low protein diets were significantly associated with sarcopenia. Multiple logistic regression analysis showed that age was a risk factor for all stages of sarcopenia, and participants above 80 years were greater than fivefold more susceptible to sarcopenia, while lower physical activity was an independent risk factor. The optimal cut‐off value for age was 71 years, which departs from the commonly accepted cut‐off of 60 years. Female participants were greater than twofold less susceptible to sarcopenia than male participants. The sterol derivative 25‐hydroxyvitamin D was associated with fourfold lower odds of sarcopenia in male participants. Several protein intake variables were also correlated with sarcopenia. Based on these parameters, we defined a highly predictive index for sarcopenia. Conclusions Our findings support a predictive index of sarcopenia, which agglomerates the complex influences that sterol metabolism and nutrition exert on male vs female participants., Dysregulated circadian clock genes were associated with glioma grades and the IDH status. Prognostic model suggests circadian clock genes affect glioma progression. The GO and GSEA enrichment analysis suggested dysregulated circadian clock genes can affect glioma through interfering cell cycle and influencing immunocytes infiltration.

The slow kinetics of the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) remain the primary problem impeding the commercialization of zinc-air batteries (ZABs). Herein, we demonstrate a hybrid composite consisting of multivalent CoSx nanoparticles and nitrogen-doped carbon nanotubes catalytically active-nickel (NCNTs/Ni) as an advanced ORR/OER electrocatalyst with excellent electrocatalytic activity. The Co-N bonds in the hybrid catalyst effectively enhance interfacial charge transfer, resulting in synergetic effects for enhanced oxygen electrochemistry. The optimized hybrid, CoSx/NCNTs/Ni-2, affords excellent performance in an alkaline ZAB, achieving a high-power density of 131 mW cm−2, and the voltage gap remained at only 0.87 V after 200 h of continuous charge–discharge at 5 mA cm−2. This study provides a facile strategy for the construction of bifunctional hybrids with non-precious metals for potential application in ZABs and other sustainable energy conversion devices.

Vanadium-based MXenes are prospective as anode materials in energy-storage devices including lithium-ion batteries (LIBs) but limited by their charge-discharge capacities. Herein, partially-etched V2AlxCTz with the average particle size of ~400 nm was synthesized using 40 wt% HF or mixed NaF+HCl solutions as etchants, respectively. V2AlxCTz etched by 40 wt% HF for 96 h at room temperature (RT) has more exceptional charge-discharge performances against mixed NaF+HCl solutions, with an average reversible capacity of ~450 mAh g−1 at 0.1 A g−1 in the 120 cycles and ~301.2 mAh g−1 at 0.5 A g−1 after 200 cycles in LIBs. The effect of etchants on electrochemical performances and lithium-ion (Li-ion) storage mechanism of V2AlxCTz was discussed comprehensively. Additionally, a Li-ion full cell using LiFePO4 as cathode has exhibited excellent electrochemical performance (150.4 mAh g−1 at 0.1 C). This work illustrates that partially-etched V2AlxCTz with the submicro-sized distribution is also a promising anode material for LIBs.

Nanosized VC with an average particle size of ∼40 nm was synthesized by disproportionation of V(IV) ions on acetylene black template in molten (Na,K)Cl at 950 °C holding for 5 h. The as-synthesized VC has exhibited desirable electrochemical performances as an anode in lithium-ion batteries (LIBs), delivered a reversible discharge capacity of 597.8 mAh•g−1 at 0.1 A•g−1 and ∼397.8 mAh•g−1 at 0.5 A•g−1 in 200 consecutive cycles. It is noteworthy that nanosized VC also displayed impressive charge-discharge capacities in sodium-ion batteries (SIBs), released ∼252.5 mAh•g−1 at 0.1 A•g−1. This work provides a new insight into the preparation of high-performance carbide ceramics as anodes in metal-ion batteries.

Titanium alloys are widely used in cryogenic engineering due to their excellent mechanical properties. In this paper, through optimizing the alloying elements and proper thermomechanical treatments, an adjustable zero thermal expansion in Ti alloy is obtained. The achieved materials show a very low coefficient of linear thermal expansion in a wide temperature region (100–623 K). Our study indicated that the thermal expansion property of the Ti alloys can be tuned by cold rolling and the thermal history. This unique alloy may potentially be developed to prepare the important parts for cryogenic practical applications as a controllable zero thermal expansion material.

Ferritic stainless steels are promising materials for application in interconnects of solid oxide fuel cells (SOFC). The present problems to be solved urgently for using ferritic stainless steels as interconnects are their rapid increase in electrical resistance and the cathode poisoning caused by evaporation of chromia. In the present study, the Ni Fe and NiFe CeO2 alloy coatings have been electro-deposited onto 430 stainless steels (430SS). During oxidation at 800 °C in air, an outer dense NiFe2O4 layer and an inner protective Cr2O3 layer have thermally grown on the coated samples. The NiFe2O4 layer retards the outward migration of chromium effectively. The addition of CeO2 reduces the growth rate of Cr2O3 and decreases the number of pores near the oxide scale/alloy interface. Moreover, a higher electrical conductivity has been achieved by the addition of CeO2.

Nitrogen is one of the most important essential macronutrients, which acts on a physiological basis as a key limiting factor for plant productivity and crop yield. As the primary source of inorganic nitrogen, ammonium is the preferential source for root uptake, especially in nitrogen-deficient plants, because its assimilation requires less energy than nitrate. To date, several ammonium transporter (AMT) genes have been isolated and partially characterized from plants other than walnut. The growth and yield of walnut trees require abundant nitrogen because of its large size. For the purpose of decreasing production costs and reducing environmental pollution, higher nitrogen utilization of walnut rootstock is desirable. In this study, an ammonium transporter gene, encoding a 52.39 kDa poly-peptide of 461 amino acids, designated JrAMT2, was isolated from walnut. JrAMT2 was expressed in all tissues of tissue cultured walnut shoots, with the highest expression in roots. Overexpression of JrAMT2 in walnut shoots resulted in darker green foliage and higher nitrogen concentration. In vitro graft experiments showed overexpression JrAMT2 rootstock can significantly increase the nitrogen level in the WT scion. This result indicates a potential approach to development of better nitrogen utilization rootstocks for walnut and other tree crops.

A zirconium diboride coating on 201 stainless steel prepared by electrodeposition in NaCl-KCl-K 2 ZrF 6 -KBF 4 molten salts and the stability and corrosion mechanism of the stainless steel with and without ZrB 2 coating in molten aluminum alloy at 800 °C are investigated by immersion tests. The results show that the stainless steels suffer severe corrosion by aluminum after only 2 h immersion, while the ZrB 2 -coated stainless steels show high corrosion resistance to aluminum attacks after 120 h immersion. It can be inferred that surface modification of stainless steel by electrodepositing ZrB 2 coating in molten salts is an effective way to protect substrate materials from degeneration in molten aluminum.

The corrosion of cast coarse grain and laser-remelting fine grain Ni-Cr alloys in molten (Li,Na,K)F at 700 °C under Ar has been investigated by electrochemical and thermogravimetric methods with an attempt to understand the effect of grain refinement on the corrosion of the alloys. The results indicate that grain refinement remarkably accelerates the dissolution of Cr, leading to the formation of a wider Cr-depleted zone. The enhanced corrosion of fine grain Ni-Cr alloys could be ascribed to the laser remelting treatment decreasing greatly the grain size of the alloys, and thus significantly increasing the overall effective diffusion coefficient of Cr.

Pteroceltis tatarinowii (Cannabaceae), a relic tree endemic to China, is mainly distributed in limestone mountains and has a wide geographical range. In this study, 12 microsatellite primer pairs were assayed to analyse the genetic pattern and gene flow among 461 individuals sampled from 23 wild populations of P. tatarinowii. A high level of genetic diversity was detected based on high values of total alleles (159), the number of alleles (NA = 6.373), expected heterozygosity (HE = 0.696) and observed heterozygosity (HO = 0.679). The high genetic diversity in this species may be attributed to its long‐life history, wide geographical distribution and wind dispersal. Only low genetic differentiation (GST = 0.137, FST = 0.138) was found among populations. Gene flow (migrants per generation, Nₘ) was estimated to be 1.56. This moderate level of gene flow possibly decrease interpopulation differentiation by buffering against genetic drift and improving gene exchange. However, spatial genetic structure was detected throughou the sampled range of the species (r = 0.311, p < 0.05) as well as in southern China (r = 0.453, p < 0.05), and may be related to terrain heterogeneity and the demographic history of P. tatarinowii. The east‐west high mountains of southern China might serve as physical barriers to seed and pollen flow. The isolation and local adaptation of different refugia may further limit gene flow. In addition, geographically remote populations might fail to effectively disperse pollen and seeds. Based on the above‐mentioned results, some suggestions for the conservation of the species are presented.