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This article is concerned with the adaptive disturbance suppression output regulation (ADSOR) problem for the switched systems (SSs) subjected to multisource disturbances. The disturbances are consisted of the measurable unmodeled disturbance and unmeasurable dynamic neural network (DNN) modeling disturbance. First, an adaptive disturbance estimator (ADE) is designed to capture the unmeasurable disturbance. Then, via the ADE, the ADSOR controller, and the switching index are co-constructed to make the regulation on the system output and the suppression on the multisource disturbances of SSs. Further, for the SSs with multisource disturbances, the criteria are derived to force the OR performance as well as the multisource disturbance resistance performance, even though the subsystems are not individually capable of achieving these performances. Finally, the turbofan model simulation verifies the applicability and validity of the developed results.

The advancement of acetylcholinesterase (AChE) activity and its inhibitor assays is crucial for clinical diagnosis, drug screening, and environmental monitoring. A nanozyme-mediated cascade reaction system could offer promising prospects for a wide range of applications in such biosensing; however, the creation of nanozyme catalysts with diverse functionalities remains a significant challenge. Herein, we have proposed a multifunctional iron-doped polymer dots (Fe-PDs) nanozyme possessing excellent fluorescence and peroxidase (POD)-mimicking activity. Notably, the Fe-PDs nanozyme is capable of catalyzing H2O2to produce a series of reactive oxygen species, which can simultaneously quench the fluorescence of Fe-PDs and induce a chromogenic reaction of 3,3′,5,5′-tetramethylbenzidine (TMB), enabling the dual-mode detection of H2O2through both fluorescence turn-off and absorbance turn-on signals. Furthermore, by integrating acetylcholine (ACh) and choline oxidase (ChOx), we have developed a three-enzyme (AChE–ChOx–POD) cascade-based fluorometric and colorimetric dual-mode sensing platform for monitoring AChE activity and its inhibitors. The sensitive and convenient dual-mode sensor has achieved low limits of detection with 0.5 mU/mL (fluorometry) and 0.014 mU/mL (colorimetry) for AChE, respectively, which are superior to the traditional Ellman’s assay. More significantly, this sensor can also be extended to detect the reversible and irreversible inhibitors of AChE, such as tacrine (IC50= 23.3 nM) and carbaryl (LOD = 0.8 nM). We firmly believe that this innovative dual-mode nanozyme-involved multienzyme cascade system-based sensing strategy will stimulate further exploration and serve as a versatile and practical tool for biochemical sensing applications.

This article focuses on the adaptive anti-disturbance bumpless transfer (AADBT) control issue for the switched neural network systems (SNNSs) encountered by the unmeasurable neural network (NN) modeled disturbance and the measurable unmodeled disturbance through the multiple Lyapunov functions method. First, an adaptive regulator is set to appropriate the unknown parameter in the NN disturbance model. Then, an adaptive disturbance observer is built to estimate the NN modeling disturbance. Further, based on the adaptive regulator and disturbance observer, a switched controller and a state-relevant switching regulator are dual designed to compensate the influence of the NN modeled disturbance and alleviate the influence of the unmodeled disturbance with the jumps in the control input are reduced. Finally, the established control scheme is applied to the switched RLC circuit model, exhibiting the effectiveness of the control strategy.

It is of great significance for the clinical diagnosis of Alzheimer's disease (AD) to achieve the on-site activity evaluation of acetylcholinesterase (AChE), the hydrolase of acetylcholine (ACh). Herein, we have developed a biosensing method endowed with considerable superiority based on the organic–inorganic hybrid composite Eu(DPA)3@Lap with excellent stability and fluorescent properties for this purpose by loading Eu3+ions and 2,6-dipicolinic acid (DPA) into LAPONITE® (Lap). Through the comprehensive consideration of the specific hydrolysis of acetylthiocholine (ATCh) into thiocholine (TCh) by AChE, the high binding affinity of TCh to copper ion (Cu2+), and the selective fluorescence quenching ability of Cu2+, a simple Eu(DPA)3@Lap-based assay was developed to realize the rapid and convenient evaluation of AChE activity. Owning to the facile signal on-off-on response mode with a clear PET-based sensing mechanism, our assay presents favorable selectivity and sensitivity (LOD of 0.5 mU mL−1). Furthermore, the fluorescent assay was successfully applied for assessing AChE activity in human serum samples and screening potential AChE inhibitors, showing potential for application in the early diagnosis and drug screening of AD, as a new development path of AD therapy.

Disentangling the relative roles of environmental and spatial processes in community assembly is a major task of community ecology. It is necessary to uncover this question at multiple spatial scales; however, the relative importance of spatial and environmental processes on ground-dwelling beetle assembly at a small scale is still unclear. Based on two permanent plots (each 300 m) located in primary mixed broadleaved-Korean pine forests, the topographic, soil, and plant factors were collected, and the spatial variables (MEMs, distance-based Moran’s eigenvector maps) were calculated. A redundancy analysis (RDA) was used to evaluate the influence of topographic, soil, and plant variables on ground-dwelling beetle compositions. A variation partitioning analysis was used to quantify the relative contributions of environmental and spatial processes on the assembly of ground-dwelling beetles. The results of the RDA reported that the soil, plant, and topographic variables affected Staphylinidae and Silphidae beetle compositions in both plots. According to the results of variation partitioning, pure soil and plant variables were important for the assembly of Silphidae beetles in the LS plot. The contributions of pure topographic, soil, and plant variables were significantly lower than those of pure spatial variables. The contributions of pure spatial variables were significant for the assembly of Staphylinidae and Silphidae beetles in both plots. In addition, the relative importance of environmental and spatial processes was not significantly changed after including more environmental variables and the unexplained variations. Finally, this study suggests that both spatial and environmental variables are important for the assembly of ground-dwelling beetle communities, while pure spatial variables are more important than pure environmental variables at a small scale (300 m).

Older adults often have difficulty in making decisions under uncertainty, increasing the risk of financial exploitation. However, it is still under investigation about the extent to which cognitive decline influences risky decision-making and the underlying neural correlates. We hypothesized that the individual differences of risk-taking behavior depend on cognitive integrity, in which the dorsal and ventral fronto-amygdala connectivity would play dissociable roles. In the current study, thirty-six young and 51 older adults were tested with the Iowa gambling task combing resting-state and task-related functional magnetic resonance imaging. The results showed significant changes in behaviors and the fronto-amygdala network in older adults relative to young adults. More importantly, age-effect on risk-taking behaviors was remarkably different in cognitively normal and impaired older adults. In resting-state analysis, task performance was positively correlated with the ventral fronto-amygdala connectivity and negatively correlated with the dorsal fronto-amygdala connectivity in cognitively impaired older adults, compared with cognitively normal individuals. Furthermore, task-related analysis confirmed the relationships between dorsal/ventral fronto-amygdala network and risk-taking behaviors depending on cognitive integrity. These findings indicate that the fronto-amygdala network is crucial for understanding altered risky decision-making in aging, suggesting dissociable contributions of the dorsal and ventral pathways in the context of cognitive decline.

Conservation tillage increases soil microarthropod abundance at the global scale.The effect of conservative tillage on microarthropods is soil texture-dependent.This positive effect of conservation tillage is particularly evident in nutrient-poor soil areas.In temperate humid regions, however, this positive effect of conservation tillage is limited.The effect of conservative tillage on microarthropods varies with fauna group and climate regions.

A novel complex comprising an ion pair of arginine–arginine carbamate is reported herein, which is isolated from an aqueous l-arginine solution after reacting with CO2. Its structure was unambiguously elucidated via single-crystal X-ray diffraction, and its phase purity was confirmed by powder X-ray diffraction (PXRD) analysis. Nuclear magnetic resonance (NMR) studies suggested that the arginine carbamate complex hydrolyzed in aqueous conditions with a rate directly proportional to its concentration. Furthermore, density functional theory (DFT) calculations revealed how the amino group acted as a nucleophile to attack CO2to enable the ion-pair formation through a proton transfer between the arginine and arginine carbamate. The discovery of the arginine–CO2adduct expands our understanding of CO2fixation and can lead to the development of new methods of implementing l-arginine or other amino acids for CO2capture technology.

ABSTRACTThis paper examines the determinants of internal audit outsourcing from the macro perspective of financial ecological environment. We find that in regions with a poor financial ecological environment, firms are more likely to outsource internal audit and more inclined to outsource to other service providers than to accounting firms that provide financial report audit services for them. Furthermore, those firms with high financing constraints and non-state-owned firms are more likely to outsource internal audit in poor financial ecological environments. Firms outsourcing internal audit in poor financial ecological environments will have low debt financing costs. These results suggest firms in weak financial ecological environments tend to use internal audit outsourcing to enhance investor confidence and reduce financing costs. This paper helps expand the literature related to the determinants of internal audit outsourcing from a macro perspective, and provide a reference for improving the resource-allocation efficiency of the governance-oriented internal audit.

Nonlinearities have been evidenced during the chatter vibration of milling. Machinability of the thin-walled part is feed rate and position-dependent, and is subject to process damping at low cutting speed. Therefore, chatter stability prediction of milling considering nonlinear cutting force, nonlinear structural stiffness and process damping is investigated. The cutting force and stiffness are established based on the polynomial model and the process damping is investigated based on the dissipated energy. The dynamic cutting force and stability lobes are solved in the time domain with coefficients updated at each iteration. By formulating the displacement as an expanded form via the perturbation method, the time-consuming solution of delay differential equations is avoided. After formulating the identification of the nonlinear model via cutting tests and modal tests, numerical simulations considering nonlinearities are carried out and compared with the analytical method. The proposed method attains high accuracy of classic time-domain solution, but with an improved computational efficiency. Finally, cutting tests are conducted to verify the prediction of cutting force and stability lobes.

Color-rendering manipulation of solar cells is drawing increasing interest, since the integration of color displaying can promote various advanced applications. However, the dual functionality of high-performance operation and easy processing remain a challenge. Here we propose a colorful perovskite solar cell (PSC) based on purely planar layers. The photonic crystal (PC), which does not interfere with the PSC processing, enables the display of high-purity colors and maintaining the number of PC layers at 4–6. The fabricated PSC with a four-layer PC successfully displays red-green-blue (RGB) colors, with the power-conversion efficiency of 10.94%, 11.01%, and 13.70%, respectively. Further study indicates that by employing a six-layer PC the PSC can obtain excellent color-displaying effect with the color gamut up to 81.8% of the standard RGB. It also shows that the design has a good tolerance to the deviation of layer thickness.

The cutter with large length-diameter ratio has wide applications in machining structural parts with deep cavity and deep hole features. However, chatter occurs as its declined dynamic stiffness. The impact damper has been utilised to suppress machining vibration due to its simplicity and effectivity. A turning cutter with large length-diameter ratio is designed based on embedded impact damper. The dynamic model is built based on mode superposition method. The influence of cutting force and damping parameters on velocity response status (linear and nonlinear) is analysed. Design parameters of the impact damper are optimised numerically for achieving linear response. Finally, modal tests and machining tests are conducted. The experimental results show that the surface roughness of workpiece (aluminium alloy 7075) is decreased from Ra 1.95 μm to Ra 1.28 μm when the spindle speed n = 500 r/min, feed rate f = 0.05 mm/r, and cutting depth ap= 0.40 mm.

Nanozymes with multiple functionalities endow biochemical sensing with more sensitive and efficient analytical performance by widening the sensing modes. Meanwhile, the target-oriented design of multifunctional nanozymes for certain biosensing remains challenging. Herein, a constructive strategy of doping iron into polymer dots (PDs) to achieve nanozymes with excellent oxidase-mimicking and peroxidase-mimicking activity is proposed. Compared with the Fe-free PDs prepared under the same mild condition, the Fe-doped PDs (Fe-PDs) exhibit greatly boosted fluorescence at 500 nm. While applying 3,3′,5,5′-tetramethylbenzidine (TMB) as a chromogenic substrate, the fluorescence of the Fe-PDs can be further quenched by oxTMB due to the inner filter effect (IFE). Inspired by this, a simple but efficient colorimetric and fluorometric dual-mode sensing platform is developed for monitoring the reducing substances ascorbic acid (AA), α-glucosidase (α-Glu), and its inhibitors (AGIs). We believe that such multifunctional enzyme-mimic materials will provoke the exploration of multimode sensing strategy with strong practicality to serve as a versatile tool in biochemical sensing.

• Nematode abundance and footprint show unimodal patterns with precipitation levels.

Exploiting time‐series data on labor laws from 39 countries, we investigate how labor power influences firms’ payouts. We find that legislative changes that strengthen labor power reduce firms’ dividend payments and total payouts. The payout restriction effect of labor power is more pronounced in firms with greater labor intensity and in firms operating in countries with broader collective bargaining coverage and more effective law enforcement. Tightened operating flexibility and excess wage extraction are two plausible channels through which labor power affects payouts. These findings indicate that labor power is another important country‐wide institution that shapes corporate payout policy.

Alkaline phosphatase (ALP) activity assay is not only significant to the clinical diagnosis of some related disease, but also momentous to the construction of ALP-based enzyme-linked immunosorbent assay (ELISA). Herein, for the first time, we have discovered that ascorbic acid (AA) can specially react with N-methylethylenediamine (N-MEDA) to generate fluorescent non-conjugated polymer dots (NCPDs) under mild conditions. On the basis of the AA-responsive emission and ALP-catalyzed hydrolysis of ascorbic acid 2-phosphate (AA2P) to AA, we have exploited a fluorometric ALP activity assay with high sensitivity and selectivity. Furthermore, by means of conventional ALP-based ELISA platform, a conceptual fluorescent ELISA has been constructed and applied in the potential clinical diagnosis, during which cardiac troponin I (cTnI), a well-established biomarker of acute myocardial infarction, has been chosen as the model target. We envision that such original fluorescent NCPDs generation-enabled ELISA could become a versatile tool in biochemical sensing and medical diagnosis in the future.

Understanding the underlying processes of how communities are structured remains a central question in community ecology. However, the mechanisms of the soil animal community are still unclear, especially for communities on a small scale. To evaluate the relative roles of biotic interactions and environmental and spatial processes in a soil collembolan community, a field experiment was carried out on a small scale (50 m) in the farmland ecosystem of the Sanjiang Plain, Northeast China. In August and October, 2011, we took 100 samples each month in a 50 m × 50 m plot using a spatially delimited sampling design. Variation partitioning was used to quantify the relative contributions of the spatial and environmental variables. A null model was selected to test for the non-randomness pattern of species co-occurrence and body size in assemblages of collembolans and to test whether the pattern observed was the result of environmental or biotic processes that structured the community on a small scale. The results showed that large variance was accounted for by spatial variables (18.99% in August and 21.83% in October, both were significant). There were relatively lower effects of environmental variation (3.56% in August and 1.45% in October, neither was significant), while the soil water content, soil pH and soybean height explained a significant portion of the variance that was observed in the spatial pattern of the collembolan community. Furthermore, the null model revealed more co-occurrence than expected by chance, suggesting that collembolan communities had a non-random co-occurrence pattern in both August and October. Additionally, environmental niche overlap and the body size ratio of co-occurrence showed that interspecific competition was not influential in collembolan community structuring. Considering all of the results together, the contributions of spatial and environmental processes were stronger than biotic interactions in the small-scale structuring of a soil collembolan community.

Abstract: A novel PdNi/TiO2 electrocatalyst for methanol oxidation is fabricated using spherical TiO2 nanoparticles as support. The structural and electrochemical properties of the PdNi/TiO2 catalyst are characterized by XRD, TEM and electrochemical analysis. The cyclic voltammograms of PdNi/TiO2 catalyst show that there is a large methanol oxidation peak in about 0.882V that is much bigger than that of the commercial PtRu/C catalyst in 0.7V. The composite TiO2 material has high catalytic activity without UV light illumination. The electrocatalytic activity and anti-poisoning capability of the PdNi/TiO2 catalyst are promising, which may become a potential candidate for direct methanol fuel cell. [Copyright &y& Elsevier]

One of the fundamental questions in community ecology is whether communities are random or formed by deterministic mechanisms. Although many efforts have been made to verify non-randomness in community structure, little is known with regard to co-occurrence patterns in above-ground and below-ground communities. In this paper, we used a null model to test non-randomness in the structure of the above-ground and below-ground mite communities in farmland of the Sanjiang Plain, Northeast China. Then, we used four tests for non-randomness to recognize species pairs that would be demonstrated as significantly aggregated or segregated co-occurrences of the above-ground and below-ground mite communities. The co-occurrence pattern of the above-ground mite community was significantly non-random in October, suggesting species segregation and hence interspecific competition. Additionally, species co-occurrence patterns did not differ from randomness in the above-ground mite community in August or in below-ground mite communities in August and October. Only one significant species pair was detected in the above-ground mite community in August, while no significant species pairs were recognized in the above-ground mite community in October or in the below-ground mite communities in August and October. The results indicate that non-randomness and significant species pairs may not be the general rule in the above-ground and below-ground mite communities in farmland of the Sanjiang Plain at the fine scale.

Three new oribatid mite species, Belbodamaeus indicus sp. n. (Damaeidae), Malaconothrus macrofoveolatus sp. n. (Malaconothridae) and Nothrus phylliformis sp. n. (Nothridae), are described from Indian soils. Belbodamaeus indicus sp. n. is clearly distinguishable from all species of Belbodamaeus by the absence of discidia, very long sensilli and morphology of parastigmatic tubercles Sa. Malaconothrus macrofoveolatus sp. n. is very similar morphologically to Malaconothrus yinae Yamamoto, Aoki, Wang & Hu, 1993 from China, however it differs from the latter by the morphology of notogastral and genital setae, size of body foveolae, epimeral formula, and number of genital setae. Nothrus phylliformis sp. n. is very similar morphologically to Nothrus mystax Mahunka, 1986 from Tanzania, however it differs from the latter by the smaller body size, length of interlamellar setae and the position of notogastral setae d 1. An identification key to known species of Belbodamaeus is presented.

Three new oribatid mite species, Belbodamaeus indicussp. n. (Damaeidae), Malaconothrus macrofoveolatussp. n. (Malaconothridae) and Nothrus phylliformissp. n. (Nothridae), are described from Indian soils. Belbodamaeus indicussp. n. is clearly distinguishable from all species of Belbodamaeusby the absence of discidia, very long sensilli and morphology of parastigmatic tubercles Sa. Malaconothrus macrofoveolatussp. n. is very similar morphologically to Malaconothrus yinaeYamamoto, Aoki, Wang & Hu, 1993 from China, however it differs from the latter by the morphology of notogastral and genital setae, size of body foveolae, epimeral formula, and number of genital setae. Nothrus phylliformissp. n. is very similar morphologically to Nothrus mystaxMahunka, 1986 from Tanzania, however it differs from the latter by the smaller body size, length of interlamellar setae and the position of notogastral setae d1. An identification key to known species of Belbodamaeusis presented.

AbstractTwo new species of Protura, Neocondeellum chaoyangensis(Protentomidae), from Changchun city, Jilin Province, and Hesperentomon liaoningensis(Hesperentomidae), from Xingcheng city, Liaoning Province, are added to the known proturan fauna of China. Neocondeellum chaoyangensisdiffers from other Neocondeellumspecies by the chaetotaxy, absence of indentations on the interior surface of acrostylus, and the width of the calyx of maxillary gland. Hesperentomon liaoningensisdiffers from all other Hesperentomonspecies by the shape of the pseudoculus.

AbstractA new species, Chosonentulus changbaiensisn. sp.and an undetermined species, Filientomonsp. from Changbai Mountain, northeastern China, are described and illustrated in the present paper.

Capacity control in perceptron decision trees is typically performed by controlling their size. We prove that other quantities can be as relevant to reduce their flexibility and combat overfitting. In particular, we provide an upper bound on the generalization error which depends both on the size of the tree and on the margin of the decision nodes. So enlarging the margin in perceptron decision trees will reduce the upper bound on generalization error. Based on this analysis, we introduce three new algorithms, which can induce large margin perceptron decision trees. To assess the effect of the large margin bias, OC1 (Journal of Artificial Intelligence Research, 1994, 2, 1–32.) of Murthy, Kasif and Salzberg, a well-known system for inducing perceptron decision trees, is used as the baseline algorithm. An extensive experimental study on real world data showed that all three new algorithms perform better or at least not significantly worse than OC1 on almost every dataset with only one exception. OC1 performed worse than the best margin-based method on every dataset.

A new species of DrawidaMichaelsen 1900, named Drawida ganiniZhang and Wu sp nov., is described from the material collected in the Muling River of Heilongjiang Province, Northeast China, and the adjacent region near Russia. The new species is morphologically similar to Drawida ghilaroviGates 1969. The molecular data were more useful for comparison of D. ghilarovisamples. D. ganiniis genetically different from D. ghilaroviby a p-distance value of 18.35 ± 1.37% based on the COI gene sequence data. Thus, Ganin and Atopkin's (2018) data validate taxonomical status of D. ganinias separated species.