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Abstract Acetylcholinesterase (AChE) inhibitors have been considered as candidates for the treatment of Alzheimer's disease (AD) and have been utilized in clinical trials. In the present study, the interactions of forsythiaside and rutin with AChE have been investigated, after discovering the inhibitory AChE activity of the two compounds. Forsythiaside and rutin both can bind to AChE to form forsythiaside-AChE and rutin-AChE complex, and thus quench the intrinsic fluorescence of AChE. The quenching mechanism, the binding sites, the binding forces, the binding constants and the energy transfer involved were studied in details. Forsythiaside and rutin show some properties in common, including the stoichiometric binding ratio of 1:1 with AChE and the full quenching of AChE fluorescence. At the same time, the two compounds distinctly present some different characters, for example, the binding constant of rutin is less than that of forsythiaside, and the interaction force and the affinity between forsythiaside and AChE are much bigger than that of rutin. Spectroscopy data and docking analysis powerfully support the findings that forsythiaside inhibit AChE activity more strongly than rutin. The current study will provide the better understanding on the nature of the possible interactions between forsythiaside and rutin with AChE. Highlights • Forsythiaside has better inhibitory effects on AChE activity than rutin • Forsythiaside and rutin quench the fluorescence of AChE by forming non-fluorescent complex with binding ratio of 1:1 • Binding constant, force and affinity of forsythiaside with AChE are much bigger than those of rutin [ABSTRACT FROM AUTHOR]

Increasing the acetylcholine level and fighting the neuroinflammation has always been taken as a treatment strategy for Alzheimer's disease (AD). Forsythoside A is a major component in Forsythia suspensa (Thunb.) Vahl (F. suspensa, Lianqiao in Chinese) that has been traditionally used as Chinese herbal medicine to treat the inflammation in China. This study examined the inhibitory acetylcholinesterase activities of Forsythoside A at chemical and biological level. Forsythoside A inhibited acetylcholinesterase in a mixed type of inhibition, with Ki of 47.68 μM. Docking analysis strongly supported these findings. In PC12 cells Forsythoside A increased cell viability and suppressed acetylcholinesterase increased by Aβ 25-35 , thus alleviated the corresponding apoptosis. Taken together, these results suggest that Forsythoside A has the protective effects on Aβ 25-35 -induced apoptosis in PC12 cells by downregulating acetylcholinesterase, making it a potential functional food ingredient or drug candidate for the treatment of AD. [ABSTRACT FROM AUTHOR]

• Graded reflection acoustic grating metamaterial(GRAGM) broaden the working bandwidth. • The GRAGM enables to realize a deep subwavelength acoustic sensing. • The strong directional response of the GRAGM is able to localize sound sources. • The GRAGM can be regarded as an acoustic antenna. Acoustic grating metamaterials (AGMs) with exotic enhancement property and remarkable directional response are promising candidates to advance the metamaterial-based acoustic sensing. In this paper, a graded reflection AGM (GRAGM) is proposed to broaden the working bandwidth and reduce the device volume. In contrast with conventional periodic AGM, GRAGM with graded slit width can be viewed as a series of combined Fabry-Perot-like (FP-like) resonators. As a result, the working band is broadened twice by combining multiple resonant bands. The added reflection plate is capable of reducing the working frequency of GRAGM by manipulating the reflection phase at the boundaries with the maximum variation over than 280 Hz, which enables the GRAGM to work in a deep subwavelength scale. Moreover, the strong directional response of the GRAGM is able to localize sound sources. These exotic properties promise a number of potential applications, such as sound source localization, condition monitoring, and remote whispering. [ABSTRACT FROM AUTHOR]

In elastic systems, the researchers have observed the topological valley edge states. However, the topological valley edge states can only enable elastic waves to propagate along the narrow interfaces. Here, we obtain the topological valley waveguide states (TVWSs) by constructing the sandwich-like plates. By virtue of the TVWSs, the transport of elastic waves in the wide straight and bent waveguides is achieved. In addition, we realize the splitting effect and converging of elastic waves according to the valley-locking property. Our research may promote the design of innovative devices about energy harvesting, sensing, and information processing. [ABSTRACT FROM AUTHOR]

Fishery fuel subsidies reduce the cost of fishery production, promote the continuous expansion of the fishing vessel scale and fishing intensity, lead to overfishing, and eventually result in the deterioration of fishery resources. Based on survey data from Rongcheng, Xiangshan and Beihai, China, in 2018 and 2019, this paper analyzes the cost-benefit, break-even and sensitivity of bottom trawlers to explore the impact of fuel subsidies on bottom trawl fishery operations in China. The results show that the fuel expenditure is the biggest production cost of bottom trawl fishery. The fishery fuel subsidies are crucial to most bottom trawling economies. With fuel subsidies, the break-even operation ratios of bottom trawlers in all three fishing areas are below 100%, and trawler operations are profitable. Without fuel subsidies, only Xiangshan's trawler operation is in a safe range and can continue to operate. The results of the sensitivity analysis show that the catch price and the fuel cost are the top two sensitivity indexes and the two most important determinants of net profit in the bottom trawl fishery operation. Without fuel subsidies a large number of bottom trawlers will withdraw from fishing and decrease fishing effort, thereby reduce the current threat to fish stocks. [ABSTRACT FROM AUTHOR]

As the number of bicyclists in urban areas continues to increase, the need to realistically model the movement and interactions of bicyclists in mixed urban traffic is rapidly gaining importance. Therefore, this paper presents an agent space model (ASM) to elucidate the movements of bicyclists and pedestrians on shared roads. The ASM model, via simulation, particularly illustrates the dispersion phenomenon observed for non-motorized road users. The mutual interactions and diverse bicyclist and pedestrian properties were also incorporated into this model. The mutual interactions were realised through agent spaces of different sizes in conflict and overtaking behaviours for the following combinations: bicyclist-to-pedestrian, bicyclist-to-bicyclist, pedestrian-to-bicyclist, and pedestrian-to-pedestrian, which were obtained through experiments. The hypothesis test indicated that different agent spaces exist for different types of interactions. The experimental data were used to obtain several variables that describe the elements of road user agent spaces, including longitudinal and lateral distances and the dynamic relationship between the longitudinal distance and speed. The simulation results indicated that with an increase in the number of pedestrians, the maximum capacity decreased and the dispersion degree increased. The following psychological and physiological factors affect the degree of dispersion of bicyclists: travelling speed, reaction time, intensity, probability of selecting the head-on direction, and probability of selecting the right-hand direction. In addition, lane formation was observed in all simulations. The results also demonstrated that dedicated bicycle lanes will significantly reduce the dispersion degree. Moreover, the safety and efficiency effects of different forms of bicycle lanes were analysed from the perspective of the degree of dispersion. The simulation results can provide specific guidelines for understanding the causes of phenomena such as dispersion and lane formation, as well as for studying the traffic dynamics, effects of dedicated bicycle lanes, and macroscopic characteristics according to different bicyclist-pedestrian ratios. • The study simulated the dispersion effect in pedestrians–bicyclists shared roads. • A model that considers agent space (AS) to describe pedestrian-bicyclist interactions is proposed. • The agent space model (ASM) can describe the dispersion phenomenon with clear physical meanings and fewer parameters. • Physiological and psychological factors influencing the degree of dispersion are revealed. • Dedicated bicycle lanes will significantly reduce the dispersion degree. [ABSTRACT FROM AUTHOR]

The primary objective of this study is to investigate the effect of geothermal energy output on carbon dioxide emissions among the European countries (EU) classified as EU27 states, within the time frame 1990 to 2021. The study adopted autoregressive-distributed lag (ARDL), and the findings show that the carbon dioxide emissions mitigate with an improvement in geothermal power production. Carbon dioxide emissions were observed to be increased by some socioeconomic factors such as population density, economic growth, and fossil fuel. Findings from this study show there could be a significant reduction in carbon dioxide emission among the EU13 emerging economies leveraging on geothermal energy growth than what will be achieved among the EU14 emerged economies. Conversely, the findings from this study also show that a significant level of reduction could be attained in carbon dioxide emission among the EU14 emerged economies as a result of aging population density than we could have among the EU13 emerging economies. Also, this study established that EU14 emerging economies could attain a significant increase in carbon dioxide emissions through fossil fuel consumption and economic growth than what will be attained among the EU13 emerging economies. The three estimators adopted in the study which are the pooled mean group, mean group, and dynamic fixed effect confirmed that the projected calculations in the study are confirmed valid. This study, therefore, recommended that European nations classified as EU27 should lay more emphasis on geothermal growth to attain energy and environmental goals. Legislators in these EU countries should focus more on policies that will ensure the security and sustainability of geothermal growth. Policymakers in these EU countries should make concerted efforts toward making policies that will promote the growth and sustainability of geothermal power, thereby cutting down the need for fossil fuel and CO2 emissions in the future time. [ABSTRACT FROM AUTHOR]

• Gradient acoustic-grating metamaterial (GAGM) can realize acoustic rainbow trapping. • Detection of weak signals based on the GAGM was proposed for the first time. • Weak signals submerged by noise can be recovered more easily in the GAGM. • The GAGM helps overcome the detection limit of conventional acoustic systems. Acoustic signals detection attracts considerable attention in many areas, such as structural healthy monitoring, biomedicine, communication and earthquake prediction. However, the useful signals are always very weak and overwhelmed by background noise. In this paper, we proposed a method based on the gradient acoustic-grating metamaterial (GAGM) to detect harmonic and periodic impulse signals for the first time. The analytic analysis indicates that the incident acoustic waves with various frequencies gradually slow down and eventually stop at different positions in the GAGM. In the numerical study, we show that acoustic rainbow trapping, realized by the GAGM, can spatially separate different frequency components accompanied by the local enhancement of their amplitudes. Moreover, in the experimental investigation, we demonstrate that the GAGM is capable of amplifying pressure amplitudes about 30 times even at different measured positions. With this acoustic system, the harmonic and periodic impulse signals submerged by background noise in the GAGM can be detected much more easily. All the results indicate that the GAGM can be regarded as a functional material or an enhanced acoustic sensing device to overcome the detection limit of conventional acoustic systems. This work opens up new vistas for weak signals detection of many areas. [ABSTRACT FROM AUTHOR]

The Yangtze River supports rich biodiversity and provides important ecosystem services for human survival and development. Indices of the ecosystem health of the river are deteriorating and an increasing proportion of the 4,300 species is at highly depleted levels or at risk of extinction, including many rare and endemic species. The purpose of this article is to (i) introduce the current status of the Yangtze River aquatic biodiversity, (ii) summarize the pressures on aquatic biodiversity in the Yangtze River Basin, and (iii) review the Yangtze River fishery protection policies that have been introduced since 1978. Governance policies have been promulgated across a range of issues and threats, ranging from fishery resource management and endangered species restoration to protection of habitat and ecology. However, despite these policy interventions, trends in fishing catch, dolphin population status and fish-based indices of biological integrity, show that the recovery effect of the Yangtze River's fishery resources has been inadequate to date. Progress toward improvement in the ecosystem health requires greater efforts in coordinating governance that responds to information from comprehensive monitoring of the Yangtze River Basin. [ABSTRACT FROM AUTHOR]

• We propose a unique bilayer design of phononic crystal slabs. • The bilayer phononic crystal slabs exhibit two kinds of valley Hall phases. • The interesting topological transport properties are realized in the bilayer slabs. In this Letter, we propose a unique bilayer design of phononic crystal slabs that are constructed by two layers of snowflake phononic crystal plates connected by a honeycomb array of cylinders. By tuning orientations of snowflake-shaped holes in both layers, we achieve two kinds of valley-projected topological elastic insulators distinguished by conventional and layer-polarized topological valley Hall phases. Then, between different conventional and layer-polarized topological valley Hall phases, two kinds of edge modes, layer-mixed and layer-polarized edge modes, are obtained and explored. In finite-size samples, the interesting topological transport properties, which the elastic wave can propagate alternatively between both layers and only in a single layer, are realized by exciting layer-mixed and layer-polarized edge states. In addition, we design an interlayer converter to realize conversion of the elastic wave propagation between both layers. Our research promotes the development of topological elastic insulators and provides a route for various practical applications. [ABSTRACT FROM AUTHOR]

Abstract In the study, the neuroprotectivities of forsythiaside, a main constituent of Forsythia suspensa (Thunb.) Vahl (F. suspensa , Lianqiao in Chinese), were investigated in the hippocampal slices. Forsythiaside suppressed the overexpression of cyclooxygenase-2 (COX-2) and monoacylglycerol lipase (MAGL) proteins induced by β-amyloid (Aβ 25-35) to upregulate the levels of 2-arachidonoylglycerol (2-AG), an endogenous endocannabinoids. Then the inhibition of forsythiaside on COX-2 was deeply studied by the molecular docking. Forsythiaside prevented neuroinflammation and apoptosis from Aβ 25-35 insults, and this action appeared to be mediated via cannabinoid receptor 1 (CB1R)-dependent nuclear factor-κB (NF-κB) signaling pathways. More importantly, forsythiaside functionally improved Aβ 25-35 -induced learning and memory deficits, which was indicated by long term potentiation (LTP). Taken together, forsythiaside may have therapeutic potential for Alzheimer's diseases (AD) by increasing the levels of 2-AG. Highlights • Forsythiaside inhibits COX-2 and MAGL over-expression induced by Aβ to up-regulate 2-AG. • Forsythiaside prevents inflammation and apoptosis from Aβ via CB1R-dependent NF-κB pathway. • Forsythiaside functionally improves Aβ-caused LTP deficits. [ABSTRACT FROM AUTHOR]