The effects of lithium, aluminum and yttrium elements on the microstructure and corrosion behavior of the Mg–Li–Al-(Y) alloys were studied by signal-to-ratio (S/N) analyses. The sequence of alloying ...elements (Li, Al and Y) affecting the corrosion behavior of the Mg–Li–Al-(Y) alloys from strong to weak is Al > Li > Y. The addition of Al affects the size and area fraction of Al-rich intermetallics. As the Li content increases, the crystal structures of Mg–Li alloys can be transfer from hcp (single α phase), hcp + bcc (α + β dual-phase), to bcc (single β phase). The addition of Y refines the grains and hinders the formation of AlLi compound. The Mg–10Li–3Al-0.6Y alloy has a better corrosion resistance mainly due to the homogeneous microstructure and uniformly distribution of short rod-like α-Mg phase with a relatively high area fraction as a corrosion barrier inhibits the severe localized dissolution of β-Li matrix. The corrosion rate of the optimized alloy of approximately 2.14 mm/y is still higher than the intrinsic corrosion rate of ultra-pure Mg of 0.3 mm/y.
•The effects of alloying elements (such as Li, Al and Y) on microstructure and corrosion behavior of the Mg–Li–Al-(Y) alloys are studied by the signal-to-ratio (S/N) analyses.•The corrosion rate tests display that the sequence of alloying elements (Li, Al and Y) affecting the corrosion resistance of the Mg–Li–Al-(Y) alloys from strong to weak is Al > Li > Y.•The Mg–10Li–3Al-0.6Y alloy has a better corrosion resistance mainly due to the homogeneous microstructure and uniformly distribution of short rod-like α-Mg phase with a relatively high area fraction as a corrosion barrier inhibits the severe localized dissolution of β-Li matrix.
The phenomena of variability and interference in the natural frequencies of weight-sensing structures applied in complex working conditions must solve the problem of reducing or eliminating resonance ...under low-frequency vibrations to maximize stability, accuracy and reliability. The influence laws of the additional mass with relevant characteristics on the natural frequencies, which include the components of mass, stiffness and center-of-mass distribution, etc. Firstly, the theoretical formulas of the mathematical model are given based on different characteristics of the weight-sensing structure, and various combinations of additional masses on the weight-sensing structures are adjusted in the X-, Y-, and Z-directions. The key factors to be specifically considered in the theoretical formulas are discussed through simulation analysis and experimental validation. Secondly, the locking strength of the fastening screws of some components was changed, and another component was placed on the experimental platform in the experiment. The results show that the mass, center-of-mass, stiffness distribution and other factors of the additional mass have different effects on the natural frequencies, which are important for the demand for high-precision, high-stability weighing measurement. The results of this research can provide an effective scientific evaluation basis for the reliable prediction of natural frequencies.
Pyrethroids are insecticides that are widely used in rural and urban areas worldwide. After entering the environment, pyrethroids are rapidly metabolized or degraded by various biological or abiotic ...methods. In this study, a single-chain variable fragment (scFv) which could simultaneously detect three pyrethroid metabolites was constructed based on a hybridoma raised against 3-phenoxybenzoic acid (3-PBA). By molecular docking, it showed that there were hydrogen bonds, hydrophobic interactions, CH-π interaction, and cation-π interaction between 3-PBA and its scFv. All the contact residues contributing to hydrogen bonds are located in VH-CDR2 or its neighboring region, and two of them were mutants of the closest germline sequence. Based on competitive ELISA, the half maximal inhibitory concentration (IC
50
) of the scFv for 3-PBA, 3-phenoxybenzaldehyde (PBAld), and 3-phenoxybenzyl alcohol (PBAlc) were calculated to be 0.55, 0.59, and 0.63 μgmL
−1
, respectively. The scFv also showed 23.91%, 13.41%, 1.15%, 1.00%, and 0.56% cross-reactivity with phenothrin, deltamethrin, fenvalerate, beta-cypermethrin, and fenpropathrin. The broad specificity of the scFv may be due to its hapten design. The scFv could be employed in class-specific immunoassays for pyrethroid metabolites with phenoxybenzyl (PB) group. It is also potentially used for characterizing degradation of pyrethroids or detecting PBAlc (PBAld) alone, and the detection results should be confirmed by other selective methods.
Key points
•
A scFv which can simultaneously detect 3-PBA, PBAlc, and PBAld was constructed.
•
Antibody informatics and binding mode of the scFv were obtained.
•
The reason for its broad specificity was discussed.
•
It could be used to monitor single or multi-pyrethroid metabolites with PB group.
•Vision-based simultaneous monitoring of shaft IRS and axial vibration was proposed.•Composite fringe pattern and linear array sensor were employed in the measurements.•It demonstrated high-precision ...performance of IRS and axial vibration measurements.
Both the instantaneous rotational speed (IRS) and vibration of a rotating shaft are key information for condition monitoring and faults diagnosis of rotary machinery. Instead of using a rotational speed encoder and a displacement sensor to measure the IRS and the vibration of a rotating shaft, a non-projection fringe pattern and vision-based system was proposed to realize simultaneous measurement of IRS and axial vibration of a rotation shaft. A composite fringe pattern (CFP) was pasted around the surface of the shaft and worked as IRS and displacement sensors. Each line fringe intensity along the axial direction contained two fringe period densities (FPDs), in which each FPD ratio only corresponds to a rotational angle. A linear array image sensor was employed to record the fringe intensity, from which the time domain rotational angle could be obtained from the change of the FPD ratio and the axial displacement could be acquired by locating the maximum peaks of the cross correlation between the recorded fringe intensity and the reference one. Thus, the IRS could be obtained accurately and efficiently from the rotational angle by multiplying the sampling frame rate of the high-speed camera. Simulated and experimental results demonstrated that the proposed system could simultaneously extract the IRS and axial displacement with the advantage of non-contact and effectiveness. Therefore, the proposed system provides an alternative vision-based approach for the simultaneous measurement of IRS and axial vibration.
Renal cell carcinoma (RCC) is the most common form of kidney cancer. Systemic therapy is the preferred method to eliminate residual cancer cells after surgery and prolong the survival of patients ...with inoperable RCC. A variety of molecular targeted and immunological therapies have been developed to improve the survival rate and prognosis of RCC patients based on their chemotherapy-resistant properties. However, owing to tumor heterogeneity and drug resistance, targeted and immunological therapies lack complete and durable anti-tumor responses; therefore, understanding the mechanisms of systemic therapy resistance and improving clinical curative effects in the treatment of RCC remain challenging.
models with traditional RCC cell lines or primary cell culture, as well as
models with cell or patient-derived xenografts, are used to explore the drug resistance mechanisms of RCC and screen new targeted therapeutic drugs. Here, we review the established methods and applications of
and
RCC drug resistance models, with the aim of improving our understanding of its resistance mechanisms, increasing the efficacy of combination medications, and providing a theoretical foundation for the development and application of new drugs, drug screening, and treatment guidelines for RCC patients.
Acute myocardial infarction (AMI) is a serious cardiovascular disease. Investigating new susceptibility genes for effective methods of early diagnosis of AMI is important. In the current study, ...peripheral blood miR-19a levels were detected by real-time polymerase chain reaction. Significant differences and logistic correlation analyses were carried out by grouping of disease types and stratification of risk factors. Receiver-operator characteristic curve analysis was used to compare the current common clinical biochemical markers and evaluate the sensitivity and specificity of miR-19a for diagnosing AMI. Circulating miR-19a expression in the AMI group was higher than that in controls. The diagnostic effect of circulating miR-19a levels was superior to current clinical biochemical indices, such as CK, CK-MB, MYO, hs-TnI, and BNP. Our results show that there is a close association of circulating miR-19a levels with susceptibility to AMI. Circulating miR-19a levels could be a candidate diagnostic biomarker for AMI.
As evidence has mounted that virus-infected cells, such as cancer cells, negatively regulate the function of T-cells via immune checkpoints, it has become increasingly clear that viral infections ...similarly exploit immune checkpoints as an immune system escape mechanism. Although immune checkpoint therapy has been successfully used in cancer treatment, numerous studies have suggested that such therapy may also be highly relevant for treating viral infection, especially chronic viral infections. However, it has not yet been applied in this manner. Here, we reviewed recent findings regarding immune checkpoints in viral infections, including COVID-19, and discussed the role of immune checkpoints in different viral infections, as well as the potential for applying immune checkpoint blockades as antiviral therapy.
Metribuzin is a broad-spectrum herbicide that allows effective weed management in fields but the contamination of metribuzin on the environment and humans is a threat to its application. To better ...monitor the residue of metribuzin in practical application, an HPLC–MS/MS method for the determination of herbicide metribuzin and its metabolites DA, DK, and DADK residues in potato tuber was developed. The matrix effects were also investigated in this work. Potato tuber samples were extracted with a mixture of acetonitrile/water (3:1, v/v) using microwave-assisted and liquid–liquid extracted by methylene chloride. Matrix-matched calibration curve prepared after spiking standards across the studied range of concentrations (0.001–0.5 mg/L) into blank potato tuber extract was excellent. Recovery studies were carried out at three concentration levels (0.01, 0.1, and 1.0 mg/kg,
n
= 3) and the rates were ranged between 72.6 and 96.7%, with relative standard deviations (RSDs) from 4.0 to 16.8% for four chemicals calculated by the matrix-matched curves with spiking internal standards. The recovery rates were found to range from 66.3 to 108.9% and with RSDs from 1.7 to 8.4% obtained from solvent calibration curves. Our results suggested that the internal standards can improve the method recoveries and accuracies. It is much more appropriate to record matrix effect and recovery separately. Moreover, the matrix effect varies with different samples and evaluation of matrix effect only once in future calculations for the different source samples or at another time is undependable. The conclusions were beneficial to developing high-accuracy and high-sensitive technology for quantitative detection of herbicide metribuzin and its metabolites.
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) can mutate frequently and many new strains have emerged thus far. The clinical and epidemiological characteristics differ with each ...dominant strain.
Obtain an understanding of the clinical characteristics of patients infected with the Omicron variants of the SARS CoV-2.
Retrospective cohort SETTINGS: Teaching hospital in China.
Data on sociodemography, signs/symptoms, hospital stay, viral shedding period, comorbidities, treatment options and final outcome were retrieved from hospital electronic medical record. We collected nasopharyngeal samples, laboratory data, and clinical data from patients admitted to the hospital with SARS CoV-2.
Clinical characteristics of the patients infected with Omicron variant of SARS CoV-2.
445 patients RESULTS: The median age was 43.0 years with a range from 2 to 75 years. Two-thirds of the participants were male and one-third were female. Almost half of the participants (51.9%) had no symptoms, whereas 48.1% had at least one symptom. Of symptomatic patients, 26.7% had mild symptoms and 21.3% had moderate symptoms. No patients were admitted with severe or critical symptoms. All patients discharged from the hospital after complete recovery without any serious complications or death. The most common symptom was cough followed by sore throat and fever. Less common symptoms were having sputum, stuffy nose, and muscle pain. Rare symptoms were weakness, headache, diarrhea, hemoptysis and nausea/vomiting.
All patients had mild to moderate symptoms. Shortness of breath was not a common symptom among the study group. No patients needed invasive oxygen therapy in this cohort.
Single center and retrospective design.
None.
Hand, foot, and mouth disease (HFMD) is a highly contagious disease in children caused by a group of enteroviruses. HFMD currently presents a major threat to infants and young children because of a ...lack of antiviral drugs in clinical practice. Drug repositioning is an attractive drug discovery strategy aimed at identifying and developing new drugs for diseases. Notably, repositioning of well-characterized therapeutics, including either approved or investigational drugs, is becoming a potential strategy to identify new treatments for virus infections. Various types of drugs, including antibacterial, cardiovascular, and anticancer agents, have been studied in relation to their therapeutic potential to treat HFMD. In this review, we summarize the major outbreaks of HFMD and the progress in drug repositioning to treat this disease. We also discuss the structural features and mode of action of these repositioned drugs and highlight the opportunities and challenges of drug repositioning for HFMD.
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