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Alzheimer’s disease (AD) is a chronic neurodegenerative disease that is characterized by the extracellular accumulation of β-amyloid (Aβ). Many studies have shown a close relationship between autophagy and the formation of Aβ. As AD develops and progresses, mitophagy diminishes insoluble Aβ, and mitochondrial dysfunction seems to be a determining factor in the pathogenesis of AD. In our previous study, we showed that β-asarone pharmacological effects in APP/PS1 transgenic mice, reducing Aβ expression. However, the specific mechanism of this effect remains unclear. In this study, AD model rats induced by intracerebroventricular injection of Aβ1-42 were randomly divided into nine groups, and medical intervention was applied to the animals for 30 days. Subsequently, spatial learning and memory were evaluated by the water maze test. Bcl-2 levels in the hippocampus were determined by western blotting (WB). The protein expression of Aβ1-42, Beclin-1, p62, PINK1, and Parkin was assessed by WB and immunohistochemistry (IHC). The data showed that after β-asarone treatment, the learning and memory of the AD rats were clearly improved compared with those of the model group. Moreover, β-asarone decreased Aβ1-42, Bcl-2, and p62 levels but increased Beclin-1 levels compared with those in the model group. In addition, we treated a group of rats with CsA to inhibit mitophagy. β-Asarone increased PINK1 and Parkin expression compared with that in the model group. The results showed that β-asarone can improve the learning and memory of rats with Aβ1-42-induced AD by effectively promoting PINK1-Parkin-mediated mitophagy. Taken together, these results suggest that β-asarone may have the capacity to become a pharmaceutical agent for the treatment of AD in the future.

We present a scheme to improve the three-photon blockade in a two-atom cavity QED system in a strong coupling regime. By using electromagnetically induced transparency technique, we show that the frequency range to realize the three-photon blockade can be broadened in the presence of the control field in the case of both in-phase and out-of-phase radiations. We also show that the three-order field correlation function g(3)(0) can be decreased considerably in the presence of the control field especially in the case of out-of-phase radiations. The scheme presented in this paper provides a good candidate to realize and improve the three-photon blockade, as well as generating anti-bunched photon pairs.

Triboelectric nanogenerator (TENG) has been proven effective in converting biomechanical energy into electrical energy, which is expected to be a new energy supply device for wearable electronics and can be utilized as a self-powered sensor. In this work, we have developed a flexible, eco-friendly, and multifunctional fish gelatin based triboelectric nanogenerator (FG-TENG) composed of fish gelatin (FG) film and poly(tetrafluoroethylene)/poly(dimethylsiloxane) (PTFE/PDMS) composite film. The open-circuit voltage (Voc), short-circuit current (Isc), and output power density of this FG-TENG could reach up to 130 V, 0.35 μA, and 45.8 μW cm-2, respectively, which were significantly higher than those of TENGs based on other commonly used positive friction materials such as aluminum foil, poly(ethylene terephthalate) (PET), and print paper. The superior performance of the FG-TENG is attributed to the strong electron-donating ability of the FG during the triboelectric process. The generated electric energy was high enough to light up 50 commercial light-emitting diodes (LEDs) directly. Importantly, owing to the high stability and excellent sensitivity of the FG-TENG, it has been used as a self-powered sensor for real-time monitoring of the human physiological signals such as finger touch, joint movement, and respiration. Furthermore, to expand the usages in real-life applications, a foldable FG-TENG was fabricated by adopting the Miura folding to monitor human movements in real time. This work provides an economical, simple, and environmental-friendly approach to fabricate a biomechanical energy harvester, which has a great potential in powering next-generation wearable electronics and monitoring human physiological signals.

This communication describes the rational design of a transparent paper-based chemosensing platform for multi-target detection by wavelength-dependent absorbance/transmittance. The platform was successfully applied in the examination of bovine serum albumin (BSA) and cholesterol in serum with a low detection limit of 0.1 μM and 0.1 mM, respectively. With low cost and high sensitivity, the paper-based platform shows great promise for multiplexed bioassays.

This paper uses machine learning tools to study the serial dependence (lead-lag relations) of commodity futures returns during the post financialization period (January 2004 – December 2019). We use LASSO (Least Absolute Shrinkage and Selection Operator) to select the predictors as the number of predictors is large relative to the number of observations. We find significant full-sample and out-of-sample predictability. In the full sample, we find that LASSO can identify a sparse set of predictors that come from economically linked commodities or are likely driven by excessive speculative trading. The out-of-sample forecasts based on the LASSO generate statistically and economically large gains. When we separate the indexed futures from the non-indexed futures and replicate the above analysis, we find that the out-of-sample performance exists in the indexed futures but disappears in the non-indexed futures. The lead-lag relations are also more significant after the advent of ETF or ETNs that track the broad futures indices such as S&P GSCI and BCOM indices, indicating that index trading due to financialization drives the excessive comovement among the commodity futures. Overall, we find that serial dependence generates significant predictability during the sample period when the performance of the long-only commodity index futures is poor.

This paper considers the team management of mutual funds, fund manager ability, performance, and holdings. We find evidence suggesting there is a positive relation between performance and team management concurrent with a negative relation between managerial ability and the use of team management. Consistent with the notion that the team management suppresses portfolio eccentricity and leads to more generic trading strategies, thereby both increasing returns and making returns less informative of fund manager ability, we also find that team management is associated with less idiosyncratic portfolio holdings and a greater loading on large capitalization, low book-to-market, and momentum stocks.

This article examines how the U.S. monetary policy surprises impact the mortgage rates in the nation and across five regions from 1990 to 2008. Regression analysis based on bootstrapping shows that surprises in the target federal funds rate (the target factor) have a significantly positive impact on the 1-year adjustable-rate mortgage (ARM) rate within the week of the Federal Open Market Committee announcements and the positive impact lasts up to 1 week after the announcements. Surprises in the future direction of the Federal Reserve monetary policy (the path factor) have significantly positive impacts on both the 1-year ARM rate and the 30-year fixed mortgage rates in the first week after the announcement. Furthermore, the responses of mortgage rates are asymmetric and affected by the size of monetary policy surprises, the stage of the business cycle and whether the monetary policy is tightening or loosening. There also exists heterogeneity in the mortgage rate pass-through process across regions and monetary policy surprises have differential impacts on the regional mortgage rates. The cross-region variations are mainly correlated with the regional housing market conditions, such as home vacancy and rental vacancy rates.

Based on high frequency data of the S&P 500 ETF from 1993-2013, we document an intraday momentum pattern: the first half-hour return on the market predicts the last half-hour return. The predictability, both statistically and economically significant, is stronger on more volatile days, on higher volume days, on recession days, and on major macroeconomic news release days. This intraday momentum is also strong for ten other most actively traded domestic and international ETFs, and two major international equity index futures. Theoretically, the intraday momentum is consistent with the trading behavior of informed traders.

OSL (Open-Short-Load) calibration is the commonly used technique for one-port RF reflection/impedance measurement. Generally, the calibration standards are assumed to be ?perfect? or traceable to ?perfect standards?. With no doubts, the imperfections on calibration standards or process of traceability will create a second-level error for measurement. Recent attempts focus on predicting the second-level error with numerical simulations. However, direct analytical expression and experimental validation have not been demonstrated yet. In this paper, analytical solution to error propagation from OSL calibration standards is derived with introducing small perturbations to these standards and using first-order approximations. It leads to sensitivity analysis for OSL calibration with imperfect standards. In order to validate the analysis, a female-to-male adapter is adopted as an error source for OSL calibration standards. By comparing the reflection measurements for the cases of calibration with/without the adapter, the analytical solution is validated experimentally.

The standard antenna method is one of the main methods for the validation of antenna test range. It is easily implemented since it doesn't need any special equipment, and it costs less workload and time. So it is believed that the standard antenna method will have a good prospect of application. The suitable type of the standard antenna for the standard antenna method is studied in the paper. Several antennas are designed, simulated and compared. Besides, the influence of the measurement accuracy of antenna dimensions on the measurement results of the antenna performance is discussed. Finally, based on an overall consideration of various factors, the pyramidal horn is proposed as the suitable standard antenna type for the standard antenna method.

RF high-power generators are extensively used for plasma etching technologies. In order to achieve high quality for the Silicon wafer process, power accuracy and stability become critical requirements for RF generators. Since a plasma chamber is regarded as a nonlinear active load, load-pull effect has been investigated thoroughly in recent years. However, power measurement is not just related to load situations. Source mismatch also plays an important role for power stability and accuracy. In this paper, power accuracy for a high-power RF generators is investigated through theoretical estimation and direct experiments. For low-reflection loads, the source-mismatch effect is dominant in power measurement error when a calibrated V-I probe is used for reflection and power measurement. In order to investigate this effect, a series of load-pull experiments have been made on a commercial RF generator with power feedback. It is shown that a given source mismatch can be greatly reduced through power feedback [14][15]. The remaining source mismatch effect becomes a comprehensive result related to three factors: the dynamics of nonlinear capacitance of the power transistors, static mismatch from the output filters and the load situation. Between the source mismatch and load reflection, there are some interesting relationships that can be used to correct the power error and thus improve system performance for the generator.

An optimal instrument control strategy for a dual-stage actuator system is presented. Resolution extension by signal conditioning and digital averaging techniques was implemented during the instrument design. The motion controller was developed based on robust PID (proportional-integral-derivative) algorithm and coarse/fine relay mechanism. The closed-loop residual noise and optimal dynamic performance are demonstrated by experiments.

We have designed and constructed a novel linear actuator with 3 A closed-loop control resolution and 50 mm travel range. Two major ultraprecision motion control techniques have been applied to this actuator: (i) a novel laser Doppler encoder system with multiple-reflection optics [D. Shu et al., Proc. SPIE 3429, 284 (1998)]; and (ii) a specially designed high-stiffness weak-link mechanism with stacked thin metal sheets having sub-Angstrom driving sensitivity with excellent stability [D. Shu et al., Nucl. Instrum. Methods Phys. Res. A 467–468, 771 (2001). In this paper, we present recent test results of this actuator with an atomic force microprobe. Applications of this new technique to synchrotron radiation instrumentation are also discussed.