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This paper presents a compact two-degrees of freedom piezo-driven positioning stage. To achieve large working stroke, the stick-slip principle was employed, and to make the stage compact, a lever-type flexure hinge mechanism (LFHM) with the L-shape structure was designed. The LFHM could tune the single-direction output displacement of the stacked piezoelectric (SPE) to be two directional motions, the main motion for stick-slip driving and the parasitic motion for the contact. The L-shape structure makes the SPE being parallel to the slider rather than vertical to it, and therefore, the stage could be compact. The positioning stage had a two-layer structure for realizing motions along x and y axes, and these two layers shared the same structure. The structure design and working principle of the stage were discussed in detail. A prototype was fabricated, and the effects of driving frequency and voltage on the output characteristics were evaluated, followed by measuring its loading capacity and frequency characteristic. Experimental results showed that the output displacement had very good linearity in both x and y axes and as well for both positive and negative motions. Especially, even for a relatively large displacement output being over 1600 μm achieved by stepping accumulation, the output displacement still maintained very good linearity, demonstrating good motion stability. Furthermore, the backward motion was quite small compared with some previous studies. In addition, the vertical load in the range of 0–2 N had quite weak effects on the output characteristics, and the first resonant frequency of the driving unit was over 1900 Hz. These results indicated that the designed x–y positioning stage not only had a compact structure but also possessed good performances, which were beneficial to its practical applications. [ABSTRACT FROM AUTHOR]

The effects of tea polyphenols and ultraviolet radiation on the growth and antioxidant activity of mung bean sprouts were investigated, followed by the changes in corresponding antioxidant enzyme activities and metabolite composition. The growth of mung bean sprouts was slightly decreased by tea polyphenols and ultraviolet radiation, but the antioxidant activity was increased. The activities of peroxidase and catalase were decreased, and the contents of vitamin C, γ-aminobutyric acid and total phenols were significantly increased by tea polyphenol treatment. While the activities of peroxidase and catalase increased by ultraviolet radiation with concomitant increase in the contents of vitamin C and total phenols. The mung bean sprouts produced following imposition of stressors such as tea polyphenols and ultraviolet radiation from stress conditions could be used as a potential functional food. [ABSTRACT FROM AUTHOR]

Random residual circular birefringence induced by a twist of single-mode fiber is the main cause of magnetic field Faraday phase error in depolarized interferometric fiber optic gyroscopes (D-IFOGs). Magnetic field Faraday phase error in D-IFOG includes both radial and axial phase errors; however, axial phase error has not been thoroughly researched and is usually neglected. A magnetic phase error model of D-IFOG along a radial direction is established by using a Jones matrix; then, the mathematical description of radial direction phase drift in D-IFOG is deduced according to the model. Based on a quadrupolar winding distribution structure in a fiber loop, a magnetic phase error model of D-IFOG along the axial direction is established, and phase drift in D-IFOG is deduced by using a coil expansion method. Theoretical analysis shows that nonreciprocal phase error in D-IFOG induced by magnetic field correlates with several factors, such as optical coherent length, optical polarization degree, etc. Then, measures to restrain the magnetic field phase error in D-IFOG are investigated, such as the new Lyot depolarizer, electromagnetic shielding, etc. Further, we experimentally present the performance of D-IFOG with the magnetic intensity of 150 Gs along axial and radial directions, respectively, and verify the effect of a new Lyot depolarizer on restraining magnetic phase error in D-IFOG. [ABSTRACT FROM AUTHOR]

Enhancement of alternative activation (M2) in microglia is a promising therapeutic target for microglia-mediated neuroinflammation. Shenqi Fuzheng Injection (SFI) is a clinical adjuvant treatment for cancer to reduce the side effects during cancer treatment, including boosting mood and improving appetite. However, the mechanism of SFI's effects on central symptoms is not clear. Therefore, using arginase 1 (Arg1) and transforming growth beta-1 (Tgfb1) as markers for M2 microglia activation, we found that compounds 1, 5, 12, 14, and 15 are the major M2-promoting constituents in SFI, which significantly upregulated Arg1 or Tgfb1 gene expression. Our results suggested that these compounds in SFI may promote M2 microglial activation and have potential uses in modulating microglial activation and alleviating neuroinflammation. [ABSTRACT FROM AUTHOR]

* Context.--The use of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serologic tests detects antibodies in the host, contributing to the identification of individuals who have been exposed to coronavirus disease 2019 (COVID-19). Objective.--To critically evaluate 2 commercially available SARS-CoV-2 serology tests. Design.--A total of 333 unique, nonduplicated serum samples obtained from COVID-19 patients (n = 170) and negative controls (n = 163) obtained before December 2019 were used in the study. Samples were tested on the Roche E411 and Abbott Architect i4000SR platforms, and results were correlated to reverse transcription polymerase chain reaction (PCR) results and clinical symptoms. Results.--There was a strong level of agreement in the qualitative results between both assays, with a Cohen j value of .840, P < .001. The specificity for both Roche and Abbott were excellent at 100%. Roche exhibited marginally better performance in the 21 days or more group with a sensitivity of 90.6% (95% CI, 75.8%-96.8%) versus an Abbott sensitivity of 84.4% (95% CI, 68.3%-93.1%), as well as in the 14- to 20-day group with a sensitivity of 85.7% (95% CI, 65.4%-95.0%) versus an Abbott sensitivity of 81.0% (95% CI, 60.0%-92.3%). Less than 14 days of symptoms groups exhibited poor sensitivity at less than 50% for both assays. The areas under curve (± standard error) for Roche (0.894 ± 0.025, P < .001) and Abbott (0.884 ± 0.026, P < .001) were very similar. Potential confounders for negative serologic results include antiretroviral medication use and pauci-symptomatic patients. Conclusions.--Specificities for high-throughput Roche and Abbott immunoassays are excellent, but users need to be cautious to interpret serologic test results after 14 days of symptoms to avoid false negatives. [ABSTRACT FROM AUTHOR]