In this paper, we report a facile method to produce large-area periodical bowl-like cobalt oxide (Co3O4) array films based on a self-assembled monolayer polystyrene sphere template and ...electrodeposition. After the template is removed, the resulting Co3O4 films consist of periodic, interconnected networks of monodisperse submicrometer pores with a diameter of 1 μm. Moreover, the individual bowl contains a large number of pores with a diameter of 50 ± 20 nm and the interstices between bowls are filled with Co3O4 nanoflakes. As a preliminary test, the electrochromic properties of the Co3O4 macrobowl arrays have been investigated and it is found that the film annealed at lower temperature exhibits better electrochromic performance. The Co3O4 array film annealed at 200 °C exhibits good electrochromism with color changes from dark gray to pale yellow and fast response times. The coloration efficiency is calculated to be 29 cm2 C−1 at 633 nm, with a variation of transmittance up to 33%.
The mechanism of H2O content in different CO2 phase states on the corrosion of pipeline steel was studied by using high-pressure corrosion simulation tests, scanning electron microscopy (SEM), energy ...dispersive X-ray spectrometry (EDS), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and water chemistry simulation calculations. The results show that the corrosion mechanism of X65 steel did not change significantly under different CO2 phase state systems, and the corrosion products were similar. As the H2O content of the system increased, the sulfur-containing products in the corrosion products increased and the degree of corrosion worsened. Additionally, because the aqueous phase formed by the liquid CO2 system contained more corrosive substances, which promote the electrochemical corrosion process of X65 steel, the corrosion degree of X65 steel in a liquid CO2 system was significantly higher than that of X65 steel in a gaseous CO2 system.
Peanut production is threatened by climate change. Damage to seedlings from low temperatures in early spring can limit yield. Plant adaptations to chilling stress remain unclear in peanut seedlings. ...It is essential to understand how peanut acquires chilling tolerance.
We evaluated effects of chilling stress on growth and recovery of peanut seedlings. We compared and analysed biological characteristics, antioxidants, photosynthesis, biochemical and physiological responses, and nutrient absorption at varying levels of chilling.
Compared with chilling‐sensitive FH18, the reduced impact of chilling stress on chilling‐tolerant NH5 was associated with reduced ROS accumulation, higher ascorbate peroxidase activity and soluble sugar content, lower soluble protein content, and smaller reductions in nutrient content during stress. After removal of chilling stress, FH18 had significant accumulation of O2•− and H2O2, which decreased photosynthesis, nutrient absorption, and transport. ROS‐scavenging reduced damage from chilling stress, allowed remobilization of nutrients, improved chilling tolerance, and restored plant functioning after chilling stress removal.
These findings provide a reference for targeted research on peanut seedling tolerance to chilling and lay the foundation for bioinformatics‐based research on peanut chilling tolerance mechanisms.
Peanut seedlings cope with chilling stress by effectively regulating antioxidant defence system, alleviating the inhibition of photosynthetic capacity, and facilitating nutrient remobilization.
Corynebacterium striatum is an emerging multidrug-resistant (MDR) pathogen of immunocompromised and chronically ill patients. The objective of these studies was to provide a detailed genomic analysis ...of disease-causing C. striatum and determine the genomic drivers of resistance and resistance-gene transmission.
A multi-institutional and prospective pathogen genomics programme flagged seven MDR C. striatum infections occurring close in time, and specifically in immunocompromised patients with underlying respiratory diseases. Whole genome sequencing was used to identify clonal relationships among strains, genetic causes of antimicrobial resistance, and their mobilization capacity. Matrix-assisted linear desorption/ionization-time-of-flight analyses of sequenced isolates provided curated content to improve rapid clinical identification in subsequent cases.
Epidemiological and genomic analyses identified a related cluster of three out of seven C. striatum among lung transplant patients who had common procedures and exposures at an outlying institution. Genomic analyses further elucidated drivers of the MDR phenotypes, including resistance genes mobilized by IS3504 and ISCg9a-like insertion sequences. Seven mobilizable resistance genes were localized to a common chromosomal region bounded by unpaired insertion sequences, suggesting that a single recombination event could spread resistance to aminoglycosides, macrolides, lincosamides and tetracyclines to naive strains.
In-depth genomic studies of MDR C. striatum reveal its capacity for clonal spread within and across healthcare institutions and identify novel vectors that can mobilize multiple forms of drug resistance, further complicating efforts to treat infections in immunocompromised populations.
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•First study of Chinese vinegar classification via volatiles using FTIR.•Spectral characteristics of the vapors from vinegars were observed.•Spectral differences among the vapors from different ...brands of vinegars were studied.•The ability of FTIR combined with chemometrics to discriminate vinegars was demonstrated.
Different brands of Chinese vinegar are similar in appearance, color and aroma, making their discrimination difficult. The compositions and concentrations of the volatiles released from different vinegars vary by raw material and brewing process and thus offer a means to discriminate vinegars. In this study, we enhanced the detection sensitivity of the infrared spectrometer by extending its optical path. We measured the infrared spectra of the volatiles from 5 brands of Chinese vinegar and observed the spectral characteristics corresponding to alcohols, esters, acids, furfural, etc. Different brands of Chinese vinegar had obviously different infrared spectra and could be classified through chemometrics analysis. Furthermore, we established classification models and demonstrated their effectiveness for classifying different brands of vinegar. This study demonstrates that long-optical-path infrared spectroscopy has the ability to discriminate Chinese vinegars with the advantages that it is fast and non-destructive and eliminates the need for sampling.
Although metal matrix composites (MMCs) possess high mechanical properties for wide potential applications, there are limited kinds of ex-situ MMCs fabricated via selective laser melting (SLM) until ...now. In this study, TiN/AISI 420 stainless steel (SS) MMCs samples were fabricated by SLM. Densification behavior, microstructure, hardness and wear performance were investigated with different TiN contents and laser powers. It was found that the addition of TiN has a strong influence on density, which was mainly attributed to its impact on laser absorptivity of powder and wettability of liquid metal. With a higher laser power, the diffusion behavior of TiN became stronger and the densification of composites was improved with a maximum relative density of 98.2%. Both of the distribution and solid-solution of TiN particles were investigated by SEM, XRD and EDS results. The optimized composites achieved a high hardness of HRC 56.7, which is 11.8% higher than that of SLMed pure AISI 420 SS. The wear performance was enhanced due to the improved hardness and TiN reinforcement particle.
Summary
Background
Adefovir and tenofovir are nucleotide analogues used as long‐term therapy of chronic hepatitis B. Side effects are few, but prolonged and high‐dose therapy has been associated with ...proximal renal tubular dysfunction (RTD).
Aim
To assess the incidence of RTD during long‐term nucleotide therapy of chronic hepatitis B.
Methods
A total of 51 patients being treated at the Clinical Center, National Institutes of Health were studied. Diagnosis of RTD required de novo appearance of at least three of five features: hypophosphataemia, hypouricaemia, serum creatinine elevation, proteinuria or glucosuria.
Results
Among 51 patients treated for 1–10 (mean 7.4) years with adefovir (n = 42), tenofovir (n = 4) or adefovir followed by tenofovir (n = 5), 7 (14%) developed RTD. Time to onset ranged from 22 to 94 (mean 49) months with an estimated 10‐year cumulative rate of 15%. All seven had low urinary percent maximal tubular reabsorption of phosphate (<82%). Patients with RTD were older (58 vs. 44 years; P = 0.01) and had lower baseline glomerular filtration rates (82 vs. 97 cc/min; P = 0.08) compared to those without; but did not differ in other features. Six patients with RTD were switched to entecavir, all subsequently had improvements in serum phosphate (2.0–3.0 mg/dL), creatinine (1.6–1.1 mg/dL), uric acid (2.7–3.8 mg/dL) and proteinuria.
Conclusions
Renal tubular dysfunction develops in 15% of patients treated with adefovir or tenofovir for 2–9 years and is partially reversible with change to other antivirals. Monitoring for serum phosphate, creatinine and urinalysis is prudent during long‐term adefovir and tenofovir therapy.
Aim
MICAL2, a cytoskeleton dynamics regulator, is identified associated with survival and metastasis of several types of cancers recently. This study was designed to investigate the role of MICAL2 in ...breast cancer cell migration as well as its underlying mechanisms.
Methods
The relationship between MICAL2 and EGF/EGFR signalling was analysed by gene overexpression and knock‐down techniques. Cell migration was measured by wound‐healing assays. Activation of EGF/EGFR signalling pathways were evaluated by immunofluorescence, qPCR, Western blotting and zymography techniques. Rac1 activity was assessed by pull‐down assay. Correlation of MICAL2 and EGFR in breast cancer specimens was examined by immunohistochemical analysis.
Results
Ectopic expression of MICAL2 in MCF‐7 cells augmented EGFR protein level, accompanied by the promotion of cell migration. Silencing MICAL2 in MDA‐MB‐231 cells destabilized EGFR and inhibited cell migration. In mechanism, the maintaining effect of MICAL2 on EGFR protein content was due to a delay in EGFR degradation. Expression of MICAL2 was also shown positively correlated with the activation of P38/HSP27 and P38/MMP9 signallings, which are the main downstream signalling cascades of EGF/EGFR involved in cell migration. Further analysis indicated that Rac1 activation contributed to the maintaining effect of MICAL2 on EGFR stability. In addition, analysis of breast cancer specimens revealed a positive correlation between MICAL2 and EGFR levels and an association between MICAL2 expression and worse prognosis.
Conclusion
MICAL2 is a major regulator of breast cancer cell migration, maintaining EGFR stability and subsequent EGFR/P38 signalling activation through inhibiting EGFR degradation in a Rac1‐dependent manner.
Three porous carbons CSC-6, CSC-7, and CSC-8 were prepared by the carbonization of zinc chloride-pretreated chestnut shells at 600, 700, and 800 degree C under N2 atmosphere and had specific surface ...areas of 1754, 1987, and 1824 m2 g-1, respectively. The microstructure and surface functional groups of samples CSCs were characterized by thermal gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and Raman spectroscopy. Electrochemical performances of CSCs-based supercapacitors were evaluated by cyclic voltammetry (CV), galvanostatic charge-discharge, self-discharge, cycle stability, and electrochemical impedance spectroscopy (EIS) in two-electrode cells. Comparative studies showed that the CSC-7-based supercapacitor exhibited the best electrochemical performance among all the CSCs-based supercapacitors. At a current density of 0.1 A g-1, the CSCs-based electrodes had the specific capacitances of 42.5, 105.4, and 83.4 F g-1 in 6 M KOH solutions for CSC-6, CSC-7, and CSC-8, respectively. With the current density up to 10 A g-1, the CSC-7-based electrode still showed a capacitance as high as 92.0 F g-1. Based on the experimental results, the relationship between the electrochemical properties of the CSCs-based supercapacitors and structural nature of samples CSCs was analyzed and discussed.
In this study, ordered macroporous carbon with a three-dimensional (3D) interconnected pore structure and a graphitic pore wall was prepared by chemical vapor deposition (CVD) of benzene using ...inverse silica opal as the template. Field-emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Raman spectrometry, nitrogen adsorption, and thermogravimetric analysis techniques were used to characterize the carbon samples. The electrochemical properties of the carbon materials as a carbon-based anode for lithium-ion batteries and as a Pt catalyst support for room-temperature methanol electrochemical oxidation were examined. It was observed that the CVD method is a simple route to fabrication of desired carbon nanostructures, affording a carbon with graphitic pore walls and uniform pores. The graphitic nature of the carbon enhances the rate performance and cyclability in lithium-ion batteries. The specific capacity was found to be further improved when SnO2 nanoparticles were supported on the carbon. The specific activity of Pt catalyst supported on the carbon materials for room-temperature methanol electrochemical oxidation was observed to be higher than that of a commercial Pt catalyst (E-TEK).
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