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Plant communities in urban wetland parks (UWP) have significant eco-healthcare benefits in terms of regulating the climate and improving the human living environment. However, factors influencing the regulation of eco-healthcare benefits are unclear. Taking Huaxi Ten Mile Beach National Urban Wetland Park as an example, the urban wetland park comprehensive healthcare index (UPCHI) was constructed based on an outdoor survey and indoor analysis to evaluate the UWP's eco-healthcare benefits. Pathway analysis was used to investigate how climatic, geographic, and plant factors interact to affect the UPCHI. The results show that, over the whole year, tree–shrub–herb showed the best performance in terms of reducing PM2.5, PM10, and noise, as well as raising negative air ion concentrations; however, human comfort performed the worst. The UPCHI was generally beyond level Ⅲ (0.49–0.58) in the spring and summer, indicating that there are eco-healthcare benefits. Overall, the deciduous tree–shrub–herb community had the highest annual mean UPCHI, and more than half of the plant communities' eco-healthcare benefits were class Ⅱ, which is very beneficial for eco-healthcare. The main direct factors on UPCHI were illumination intensity (0.68) and tree height (0.90), while canopy height (0.64–0.59) and tree crown radius/canopy height (0.72–0.14) directly or indirectly influenced UPCHI. The distance from the edge of the mountain (−0.39–−0.322) had a direct negative, but minor, effect on UPCHI. This study will assist residents with selecting suitable times and places for wetland recreation and healthcare activities, and it offers a valuable reference for the future planning and design of UWP plant communities. [ABSTRACT FROM AUTHOR]

2D ferromagnet is a good platform to investigate topological effects and spintronic devices owing to its rich spin structures and excellent external‐field tunability. The appearance of the topological Hall Effect (THE) is often regarded as an important sign of the generation of chiral spin textures, like magnetic vortexes or skyrmions. Here, interface engineering and an in‐plane current are used to modulate the magnetic properties of the nearly room‐temperature 2D ferromagnet Fe5GeTe2. An artificial topology phenomenon is observed in the Fe5GeTe2/MnPS3 heterostructure by using both anomalous Hall Effect and reflective magnetic circular dichroism (RMCD) measurements. Through tuning the applied current and the RMCD laser wavelength, the amplitude of the humps and dips observed in the hysteresis loops can be modulated accordingly. Magnetic field‐dependent hysteresis loops demonstrate that the observed artificial topological phenomena are induced by the generation and annihilation of the magnetic domains. This work provides an optical method for investigating the topological‐like effects in magnetic structures and proposes an effective way to modulate the magnetic properties of magnetic materials, which is important for developing magnetic and spintronic devices in van der Waals magnetic materials. [ABSTRACT FROM AUTHOR]

The symbiosis between ectomycorrhizal (ECM) fungal species and the root system of Pinus massoniana is important for its growth. However, the characteristics of ECM fungal communities and their relationships with extracellular enzyme activities and nutrients in the rhizosphere soil of different P. massoniana genotypes have not been well characterized. In this study, P. massoniana families (groups of offspring from different parents) with different levels of growth were selected for investigating ECM fungal communities, soil nutrients, extracellular enzyme activity, and leaf nutrient concentrations to explore the relationships between P. massoniana and the composition of the ECM fungal community. The high-growth (HG) family of P. massoniana had more different ECM fungal communities than the medium-growth (MG) and low-growth (LG) families; each family had a unique and dominant genera (HG: Amphinema and Pseudoclathrosphaerina; MG: Russula and Auricularia; and LG: Russula and Amanita). Amphinema was the main contributor to the differences among the three families (contribution: HG-MG 0.225 and HG-LG 0.17) and had rich extramatrical mycelium, which favored the growth of the HG family and positively affected the accumulation of soil organic carbon. Structural equation modelling showed that the dominant genera in the HG family had significant positive effects on the activity of three extracellular enzymes (BG, NAG, and AP) (weak to moderate positive effects of Amphinema on BG, NAG, and AP and moderate positive effects of Pseudoclathrosphaerina on BG, NAG, and AP), which might have contributed to the differences in extracellular enzyme activities among the families with different growth levels. Redundancy analysis indicated that P. massoniana growth traits (tree height, diameter at breast height, and timber volume), soil total nitrogen, and the N/P ratio significantly influenced ECM fungal communities. The study revealed the characteristics of ECM fungal communities, soil extracellular enzyme activity, and nutrient features of P. massoniana with different growth levels, which help improve our understanding of the relationship between P. massoniana genotype and ECM fungal communities. [ABSTRACT FROM AUTHOR]

We present a new CUSUM procedure for sequential change-point detection in self- and mutually-exciting point processes (specifically, Hawkes networks) using discrete events data. Hawkes networks have become a popular model in statistics and machine learning, primarily due to their capability in modeling irregularly observed data where the timing between events carries a lot of information. The problem of detecting abrupt changes in Hawkes networks arises from various applications, including neuroengineering, sensor networks, and social network monitoring. Despite this, there has not been an efficient online algorithm for detecting such changes from sequential data. To this end, we propose an online recursive implementation of the CUSUM statistic for Hawkes processes, which is computationally and memory-efficient and can be decentralized for distributed computing. We first prove theoretical properties of this new CUSUM procedure, then show the improved performance of this approach over existing methods, including the Shewhart procedure based on count data, the generalized likelihood ratio statistic, and the standard score statistic. This is demonstrated via simulation studies and an application to population code change-detection in neuroengineering. [ABSTRACT FROM AUTHOR]

GeSe is a layered p-type semiconductor with intriguing optoelectrical properties such as high absorption coefficient, high carrier mobility, and narrow bandgap, which promises a broadband photoresponse over a wide spectral range. However, GeSe based broadband photodetectors could not achieve both high responsivity and fast response speed. Therefore, it is urgent to improve the properties of GeSe based broadband photodetectors. Herein, a GeSe/MoTe2 van der Waals (vdW) heterostructure was designed. The GeSe/MoTe2 vdW heterostructure possesses broadband photodetection over ultraviolet, visible, and near infrared. The device has competitive responsivity (R) and detectivity (D*) over a broadband even at 1050 nm, which are 28.4 A/W and 5.6 × 109 Jones, respectively. Excitingly, the response speed for 365 nm is as fast as 3 μs, which is much faster than most other GeSe devices. Overall, our results suggest that the GeSe/MoTe2 heterostructure can provide an effective strategy to achieve broadband photodetectors with both high responsivity and fast response. [ABSTRACT FROM AUTHOR]

Light manipulation has promoted applications in all‐optical processing. 2D anisotropic rare earth (RE) materials are promising for light modulation to realize information transmission and encryption due to the unique optical behaviors of RE ions. Here, image transmission and encryption have been realized by using 2D anisotropic RE material Eu2O3. The polarized photoluminescence (PL) of Eu2O3 has been innovatively applied for information transmission by switching the on/off states. The opposite two modes of polarization‐dependent PL have been applied to grayscale‐resolved image transmission and encryption with high security. This novel approach, polarization manipulation on the PL of 2D anisotropic RE materials, will shed light on the development of information processing, all‐optical switch, and all‐optical computation. [ABSTRACT FROM AUTHOR]

2D materials have shown great promise for next‐generation high‐performance photodetectors. However, the performance of photodetectors based on 2D materials is generally limited by the tradeoff between photoresponsivity and photodetectivity. Here, a novel junction field‐effect transistor (JFET) photodetector consisting of a PdSe2 gate and MoS2 channel is constructed to realize high responsivity and high detectivity through effective modulation of top junction gate and back gate. The JFET exhibits high carrier mobility of 213 cm2 V−1 s−1. What is more, the high responsivity of 6 × 102 A W−1, as well as the high detectivity of 1011 Jones, are achieved simultaneously through the dual‐gate modulation. The high performance is attributed to the modulation of the depletion region by the dual‐gate, which can effectively suppress the dark current and enhance the photocurrent, thereby realizing high detectivity and responsivity. The JFET photodetector provides a new approach to realize photodetectors with high responsivity and detectivity. [ABSTRACT FROM AUTHOR]