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Under the framework of a hybrid-index model, this paper investigates safe control problems of state-dependent random impulsive logical control networks (RILCNs) on both finite and infinite horizons, respectively. By using the ξ -domain method and the constructed transition probability matrix, the necessary and sufficient conditions for the solvability of safe control problems have been established. Further, based on the technique of state-space partition, two algorithms are proposed to design feedback controllers such that RILCNs can achieve the goal of safe control. Finally, two examples are shared to demonstrate the main results. [ABSTRACT FROM AUTHOR]

The authors are motivated to develop a series of hydrochromic copolymers with fast response, reversibility, repeatability, and visual transparency transition. The hydrochromic block copolymers are based on the rational ratio of hydrophilic segments of poloxamer block and hydrophobic segments of ethyl cellulose according to the preparation method of polyurethane. By tuning the ratio of hydrophilic segments or adding hygroscopic salts, the hydrochromic polymer is endowed with the ability to visualize the transparency in response to the relative humidity. Especially, the response time of the polymer is extremely shortened, up to 1 s for the optimized sample. Within the moisture stimulation, the hygroscopic swelling increases the film thickness, leading to a reversible transparency switching from a highly transparent state (82%) to an opaque white state (20.5%). [ABSTRACT FROM AUTHOR]

The stabilizing switching signal design of discrete-time linear compartmental switched systems (DT-LCSSs) has been heretofore unsolved. It has been proven that a DT-LCSS is stabilizable if and only if it is stabilizable by a periodic switching signal. However, it still needs to be determined whether the period of a stabilizing switching signal can be confined within a bound. Moreover, the existing design method for stabilizing periodic switching signals requires the diagonal entries of system matrices of all subsystems to be strictly positive. In this study, we propose a novel approach to solve this problem completely. We construct a discrete-time Markov chain for a given DT-LCSS, termed the associated Markov chain, and prove the equivalence of stability and stabilizability between the DT-LCSS and the associated Markov chain. Based on this, verifiable necessary and sufficient conditions for stability and stabilizability are derived. Especially, the period of a stabilizing switching signal for an n -dimensional DT-LCSS can always be chosen within the bound n 2 − n + 1. We propose a state-independent stabilizing switching signal design method for general stabilizable DT-LCSSs. We also prove the equivalence between stabilizability by state-independent switching laws and stabilizability by state-dependent switching laws. A state-dependent global stabilizing switching signal design method is also proposed. Additionally, the proposed results are applied to the consensus analysis of discrete-time leader–follower multi-agent systems with switching communication digraphs. The effectiveness of the theoretical results is demonstrated by examples. [ABSTRACT FROM AUTHOR]

Developing new materials that could identify fingerprint using the naked eye and observe the level 3 microscopic details is challenging. Here, we designed a novel hydrochromic and piezochromic dual-responsive optical film, which achieved the visual transparency transition. The performances of hydrochromic and piezochromic responses from high transparency to opaque whiteness were attributed to the introduction of poloxamer. The hygroscopic swelling of the disordered micelles led to light scattering, causing the hydrochromic response. The piezochromic response may be ascribed to the microcracks in the fragments of poloxamer crystals, which changed the refractive index of light. The fascinating combination of hydrochromic and piezochromic response was effectively applied in fingerprint identification. Hydrochromic response accurately recognized sweat pores, and piezochromic response could gradually reveal the ridges and valleys according to the different color of imprinted fingerprints. The film could identify fake fingerprints based on the differences in sweat pores between fake fingerprints and living fingers. More importantly, the film could easily detected not only the clear ridges but also the detailed sweat pores using the naked eye, indicating that the film has profound research significance in fingerprint analysis and liveness fingerprint detection. [Display omitted] • A novel hydrochromic and mechanochromic dual-responsive optical film was prepared. • The film has visual color transition from high transparency to opaque whiteness. • The film clearly detected the visual ridges and the detailed sweat pores. • Hydrochromic response accurately recognized sweat pores. • Piezochromic response revealed imprinted fingerprints and distinguished ridges. [ABSTRACT FROM AUTHOR]

Developing new materials that could identify fingerprint using the naked eye and observe the level 3 microscopic details is challenging. Here, we designed a novel hydrochromic and piezochromic dual-responsive optical film, which achieved the visual transparency transition. The performances of hydrochromic and piezochromic responses from high transparency to opaque whiteness were attributed to the introduction of poloxamer. The hygroscopic swelling of the disordered micelles led to light scattering, causing the hydrochromic response. The piezochromic response may be ascribed to the microcracks in the fragments of poloxamer crystals, which changed the refractive index of light. The fascinating combination of hydrochromic and piezochromic response was effectively applied in fingerprint identification. Hydrochromic response accurately recognized sweat pores, and piezochromic response could gradually reveal the ridges and valleys according to the different color of imprinted fingerprints. The film could identify fake fingerprints based on the differences in sweat pores between fake fingerprints and living fingers. More importantly, the film could easily detected not only the clear ridges but also the detailed sweat pores using the naked eye, indicating that the film has profound research significance in fingerprint analysis and liveness fingerprint detection. [Display omitted] • A novel hydrochromic and mechanochromic dual-responsive optical film was prepared. • The film has visual color transition from high transparency to opaque whiteness. • The film clearly detected the visual ridges and the detailed sweat pores. • Hydrochromic response accurately recognized sweat pores. • Piezochromic response revealed imprinted fingerprints and distinguished ridges. [ABSTRACT FROM AUTHOR]

Multiagent dynamic task assignment of forest fires is a complicated optimization problem because it requires the consideration of multiple factors, such as the spread speed of fires, firefighting speed of agents, the movement speed of agents, and the number of deployed agents. In this article, we investigate multiagent dynamic task assignment based on a forest fire point model, the objective of which is to minimize task completion time. First, we establish a model for the spread of fire and dynamic task assignments. Second, we prove that the optimal static task assignment always makes all task completion times the same under certain assumptions. Furthermore, we calculate the optimal solution to the static task assignment problem assuming no travel time for the agents, which provides the theoretical basis for the initial deployment and dynamic deployment. Third, we propose a dynamic task assignment scheme based on the global information, which ensures that every reassignment reduces the task completion time and makes all task completion times close to each other. Finally, the simulation is carried out on the MATLAB platform to verify the performance of the proposed dynamic task assignment scheme by comparing with a multistage global auction algorithm. We hope that this work provides insight for decision-makers designing reasonable assignment strategies based on the model and solving assignment optimization problem in different situations. Note to practitioners—The forest firefighting problem considered in this article is a typical multitask and multistage optimization problem. Many searching algorithms for multistage optimization problem are available in the existing literature. However, one of the main challenges is that the time of searching increases exponentially with the number of stages. This work first proves that the tasks are completed in the minimum amount of time, under the constraint of one-shot assignment. This finding helps us to evaluate the gap between the searching algorithm and the optimal solution. In addition, in practice, if the underlying dynamic process can be modeled or partially modeled, then we can predict the behavior of future stages and reduce the searching domain. If a model is available, then we can also adjust the assignment scheme dynamically based on the principle that each adjustment would reduce the total time of tasks completion. In this article, we establish a dynamical fire-spreading model and propose a model-based solution to the multistage optimization problems. The findings in this work can serve as a supplement to the existing optimization algorithms. [ABSTRACT FROM AUTHOR]

Exploring functional paper-based materials in advanced electronics meets the requirements of high-value utilization of biological resources and sustainable development. Herein, a facile strategy of impregnating cellulose-based polyurethane into cellulose paper was developed to fabricate highly transparent paper with desirable requirements. The novelty of this work lies in the development of a sustainable technology to prepare highly transparent and hazy paper, which uses a facile impregnation treatment of cellulose-based polyurethane to obtain functional paper with high transparency, high optical haze, low surface roughness, hydrophobicity, excellent tensile strength, water barrier property, and shape memory behavior. The desirable characteristics were attributed to the tight combination of cellulose paper and cellulose-based polyurethane based on covalent and hydrogen bonds. The desirable properties of highly transparent paper included high optical transmittance (84.1% at 800 nm), high optical haze (92.6% at 800 nm), low root-mean-square roughness (0.28 nm), excellent tensile strength (37.62 MPa), hydrophobicity (water contact angle of 115.5°), water barrier property, and shape memory behavior. Especially, the transparent paper with carbon nanotubes lines has high conductivity even after bending, folding and immersing. The ideal characteristics of highly transparent and hazy paper provide vast opportunities for the development of flexible electronic devices. [Display omitted] • A facile strategy by impregnating paper with functional polymers was developed. • Transparent paper was endowed with high transmittance, high haze and hydrophobicity. • Ideal characteristics were attributed to the functional cellulose-based polyurethane. • Transparent paper possess a minimum surface roughness compared with previous studies. • Transparent paper with CNTs has high conductivity even after folding and immersing. [ABSTRACT FROM AUTHOR]

In this paper, the set reachability and observability of probabilistic Boolean networks (PBNs) are investigated. Using a parallel extension technique, we proved that the observability problem of a PBN can be recast as a set reachability problem of an interconnected PBN. For set reachability analysis, we designed a random logic dynamical system (RLDS) from the PBN under consideration by reconstructing the state transfer graph (STG). We proved that, for a PBN, a target subset is reachable from an initial subset if and only if all solutions to the corresponding RLDS starting from the initial subset converge to the zero state. Based on the STG reconstruction technique and using the largest invariant subset algorithm, the necessary and sufficient conditions for finite-time set reachability with probability one and asymptotical set reachability in distribution were obtained. All the results are expressed in terms of the transition probability matrix between non-zero states of the RLDS. Further, the results related to set reachability were applied to the observability problem of PBNs. The necessary and sufficient conditions for finite-time observability with probability one and asymptotical observability in distribution were obtained. Finally, examples were presented to illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

A switching feedback has more flexibility in stabilizing systems compared to a feedback being continuous in state. In practice, a system controlled by a state-triggered switching law exhibits more robustness than by a time-triggered one. However, designing an admissible switching law in the static feedback form is difficult or even impossible when the switching sequence is subjected to certain constraints, such as the minimum dwell-time constraints. This study proposes a class of switching feedbacks with dynamic switching logic for discrete-time switched systems with constrained switching. First, a logic dynamic generator (LDG) is constructed to generate all admissible switching sequences. By combining the switched system with the LDG, the original switched system is transformed into a switched system without constraint on switching. Then, the logic and the continuous states are merged by using the theories of the semi-tensor product (STP) of matrices and the vector-representation of logic. Using this technique, the problem considered is then transformed into a problem of designing a state-triggered switching feedback for a merged switched system without constraints, and then to a problem of solving a set of bilinear matrix inequalities. Examples show that the proposed switching law with dynamic logic can stabilize certain switched systems that cannot be stabilized by existing switching laws in the static feedback form. [ABSTRACT FROM AUTHOR]

This paper redefines the observability matrix and defines the observability index for Boolean networks (BNs). In the new definition, a BN is observable if and only if the observability matrix is of full rank. The observability matrix is calculated by a simple algorithm and is applied to the problem of distinguishability of partitions. A partition of the state space is said to be distinguishable if any two distinct subsets are distinguishable, and the finest distinguishable partition (FDP) is finer than any other distinguishable partition. A necessary and sufficient condition is proposed for checking the distinguishability of any given partition, and an algorithm is proposed for calculating the FDP. The proposed results are illustrated by examples. [ABSTRACT FROM AUTHOR]

Aflatoxin B 1 (AFB 1) contamination in peanut oil is a serious food safety concern. Classical edible oil refining process is an effective approach to remove AFB 1. However, the transformation pathway, structure, and distribution of the transformation product of AFB 1 in edible oil refining have not yet been reported in detail. In this work, we demonstrated that the degumming and deacidification were the critical phases for AFB 1 removal from crude oil, in which 4.77% and 7.32% of AFB 1 were transferred into the colloidal impurities and soap stock, and 87.91% of AFB 1 was transformed to other compound. UPLC-Q-TOF MS and NMR analysis revealed that the AFB 1 transformation product in peanut oil refining resulted from the hydrolysis of the lactone ring of AFB 1. The lactone ring opened AFB 1 (named OP-AFB 1) in the soap stock can be converted into the original AFB 1 under acidic conditions. Thus, the OP-AFB 1 in soap stock was further detoxified via the Fenton treatment. [Display omitted] • The transformation pathway, structure, and distribution of the AFB 1 transformation product during peanut oil refining were described. • The Fenton reaction was used to further detoxify AFB 1 transformation product. • The AFB 1 elimination in edible oil refining provides a powerful theoretical basis for the safety of refined edible oil. [ABSTRACT FROM AUTHOR]

In this study, the authors investigate the stabilisation of Boolean control networks (BCNs) with state‐dependent constraints. A BCN with constraints is converted to a logical control system (LCS) defined in extended state space and input space. Then, a pre‐feedback is designed to transfer the resulting LCS with state‐dependent input constraints into an LCS with free control inputs. With this method, a necessary and sufficient condition for stabilisability is obtained, and a procedure is proposed to obtain all time‐optimal feedback stabilisers. An illustrative example is given to explain the proposed method. [ABSTRACT FROM AUTHOR]

This paper investigates the time-optimal state-feedback stabilization of switched Boolean control networks (SBCNs). Based on the properties of the semi-tensor product (STP) of matrices, a technique is proposed to merge the switching signal and all inputs of subnetworks into a single input variable. This technique allows us to transfer a SBCN to an equivalent non-switching logical control network (LCN) and eases the analysis and design process significantly. So long as a state-feedback stabilizer is obtained for the resulting non-switching LCN, it can then be decomposed uniquely into the respective state feedbacks of the sub-networks and the state-dependent switching law. Based on this technique, the controllability and stabilisability of such SBCNs are solved and an algorithm for finding all time-optimal switching state feedbacks is proposed. An example is described to illustrate the main results and the design process proposed in this paper. [ABSTRACT FROM AUTHOR]

This paper studies the mean-square stability of discrete-time linear switched systems with random switching, where the switching signal is the output of a logic dynamical switching model driven by an independent and identically distributed (i.i.d.) process. This class of switching is referred to as the modeled random switching. By regarding the switching model as a part of the system, a combined switched system with i.i.d. switching is obtained, which is of a hybrid nature, that is, the augmented state vector has both logic and continuous components. The semi-tensor product of matrices and the vector representation of logic are applied to merge the logic and the continuous components of the state. The equivalence between the mean-square stability of the original switched system and that of the merged switched system under i.i.d. switching is proved. By deriving the dynamics of the column-stacking form of the covariance matrix, necessary and sufficient conditions of mean-square stability for discrete-time linear switched systems with modeled random switching are obtained. An illustrative example is provided to demonstrate the usage of the proposed results. [ABSTRACT FROM AUTHOR]

It is challenging and attractive to prepare the bio-based polymers with comparable or even improved properties in terms of sustainability and economics. Here, the cellulose-based polyurethane films with ethyl cellulose as a soft segment to fully substitute polyether polyols were prepared in a facile and environmentally friendly preparation process. Moreover, the selected sample exhibited high transparency (transmittance of 84.4%), good shape memory behavior (shape fixation ratio of 95% and shape recovery ratio of 94.4%), tensile strength (9.2 MPa), good biodegradability (degradation half-life (t 1/2) of 38 d) and excellent reprocessability (recycled 10 times). Especially, the cellulose-based polyurethane films performed the role of adhesive bonding with the different substrates. In addition, by adding Al 2 O 3 nanoparticles, the EC-PU composites not only exhibited high transparency and excellent adhesive strength but also improved thermal conductivity. At a low filler loading (2.5 wt%) of Al 2 O 3 nanoparticles (30 nm), the Al 2 O 3 -EC-PU4 film not only maintained higher transmittance of 73.6% but also had excellent lap-shear strength of 3.04 MPa. Moreover, both the thermal conductivity and thermal diffusivity of Al 2 O 3 -EC-PU4 film reached as high as 0.92 W/mK and 14.81 mm2/s, which are 146% and 1048% higher than the blank sample. Therefore, it has great potential in developing high performance bio-based plastics and transparent electronic fields. [ABSTRACT FROM AUTHOR]

This study addresses the set stability of Boolean networks (BNs) and set stabilization of Boolean control networks (BCNs). Set stability determines whether a BN converges to a given subset, whereas set stabilizability addresses the issue of whether a BCN can be stabilized to a given subset. Many problems can be viewed as special cases of set stability and set stabilization, including synchronization, partial stability, and partial stabilization problems. The concepts of invariant subset and control invariant subset are introduced. Then, algorithms for the largest invariant subset and the largest control invariant subset contained in a given subset are proposed. Based on the invariant subsets obtained, the necessary and sufficient conditions for set stability and set stabilizability are established, and formulae are provided to calculate the shortest transient periods for respective initial states. A design procedure is proposed for finding all the time-optimal set stabilizers. Finally, an example is used to show the application of the proposed results to the synchronization problem of BNs. [ABSTRACT FROM AUTHOR]

Pore fluid is an important factor affecting the acoustical properties of reservoirs. Generally, variations in the physical parameters of rocks reflect their hydrocarbon saturation status. The intrinsic fluid sensitivity of these parameters can be quantified by the fluid sensitivity indicator (FSI). However, in practical application, the parameters selected by the FSI may not clearly separate fluid saturation statuses because of significant data perturbation (usually by lithology/structure variations in heterogeneous formations). Consequently, we introduced two dimensionless statistical measures: coefficient of data dispersion (CD), which represents the level of data perturbation, and overlap ratio (OR), which quantifies the discriminatory ability of two fluid saturation statuses in 1D/2D plots. The CD and OR provide tools for prescreening data and evaluating different rock physics parameters. They were successfully implemented on one set of synthetic data and two real datasets and yielded better results than FSI-derived parameters. For data from the sandstones of Daqing Oilfield (northeast China), the parameters obtained from OR reduced the overlap in the 1D and 2D parameter displays by up to 22.4% and 23.2%, respectively, relative to the parameters derived from the FSI. In the field example of the Sichuan Basin, China, the gas and brine layers are predicted based on crossplot analysis. [ABSTRACT FROM AUTHOR]

This paper considers track-following control of four-bar structured hard disk drive (HDD) systems. Compared with the traditional single-arm HDD, the four-bar structure potentially leads to higher achievable closed-loop bandwidth, but also brings challenges in control design due to nonlinearity. In track-following control design, exact linearization is impossible in practice due to mechanic resonances and measurement constraints. In this paper, instead of exact linearization, we propose a kind of prefilter to compensate for the low-frequency nonlinearities so that the compensated system has the same linear approximation at different track positions subjected to different high-frequency resonances. With this prefilter, many existing track-following control methods can be applied to the compensated plant. In this paper, H\infty loop shaping is used and simulation results show that the resulting controller preserves similar track-following performance at different track positions. [ABSTRACT FROM PUBLISHER]

Context: Photosynthetic electron transport and apparatus are highly susceptible to abiotic stressors during photosynthesis. Hordeum jubatum L. is an ornamental grass with excellent salt tolerance, used for soil improvement and ecological restoration in Northeast China. However, the comparative effects of salt, alkali and drought conditions on the photosynthetic apparatus of H. jubatum under uniform water potential are little known. Aims: We explored the photosynthetic response of H. jubatum to uniform levels of water potential stress induced by three different stressors: salt, alkali and drought. Methods: Seedlings of H. jubatum were irrigated with three concentrations of NaCl, NaHCO3 and PEG-6000 to induce water potentials of −0.21, −0.47 and −0.82 MPa. Transient fluorescence of chlorophyll a in the seedlings was measured, and JIP-test parameters were obtained. Key results: Lower values of J–I phase fluorescence intensity and appearance of a K -band under stress treatments indicated restricted electron transfer from the oxygen-evolving complex in the donor of photosystem II. In addition, the values of Δ I -band and parameters M O and N increased, whereas those of S m, ϕ Eo and ψ O decreased, indicating interruption of electron flow between electron acceptors pheophytin and NADP+. Serious adverse effects of alkali stress on the acceptors were observed; the low water potential induced by NaHCO3 damaged the thylakoid membrane on the chloroplast, resulting in increased degradation of D1 protein. Conclusions: The results suggest that H. jubatum seedlings have greater tolerance to salt and drought stress, but are highly sensitive to alkali stress in the photosynthetic system. Implications: This study provides physiological information for the successful cultivation of H. jubatum under adverse environment conditions. We compared the photosynthetic performance in seedlings of the ornamental grass Hordeum jubatum under salt, alkali and drought conditions by measuring the transient fluorescence of chlorophyll a at uniform levels of low water potential. Results showed that all three stressors inhibited photosynthetic electron transport and apparatus of H. jubatum seedlings, with the most serious effects under alkali stress. These finding will be useful when deciding on cultivation of this grass in adverse environments. [ABSTRACT FROM AUTHOR]

Abstract: The main difficulty in stability analysis of reset control systems comes from their state-dependent reset mechanism. It becomes more challenging when output matrix suffers from uncertainties which make the reset time instants uncertain. In this paper, existing quadratic stability results for uncertainty-free reset systems are extended to the case with uncertainty in the output matrix. By constructing special parameter-dependent full rank annihilators of the output matrix, it is proved that the dissipativeness of reset action is equivalent to the feasibility of an LMI plus some structural constraints on the Lyapunov matrix. For the time-varying uncertainty case, necessary and sufficient conditions for quadratic stability are obtained. For the constant uncertainty case, a sufficient condition for affine quadratic stability is also obtained. All the results are given in terms of LMIs which can be efficiently verified. [Copyright &y& Elsevier]

Abstract: In a reset control system, reset actions are usually triggered whenever a continuous signal crosses a hyperplane. In the computer-based implementation, however, the continuous triggering signal is sampled and the triggering condition is then replaced by a discrete-time counterpart. In this work, we are concerned with the stability analysis and design of reset control systems based directly on discrete-time triggering conditions. First, a relationship between reset control systems and switched systems is established and some stability criteria are then obtained. Second, it is revealed through an example that a well-designed reset control system can be regarded as a hybrid system combining an underdamped baseline system with an overdamped reset mode. The reset matrix, which is assumed to be zero in general, can be adjusted to increase the damping ratio and thus further improve the transient performance. Based on this observation, a design guideline for single-input and single-output (SISO) systems is proposed. Lastly, a hard disk drive example is investigated to demonstrate the proposed design procedure. [Copyright &y& Elsevier]

Abstract: This paper investigates stability analysis and design of reset control systems where the reset time instants are pre-specified. Firstly, in order to quantify stability of reset control systems, we propose an approach which does not rely on the stability of base linear systems. Based on this, some Lie-algebraic conditions for stability of reset control systems are obtained. Then, we develop a method for reset law design which aims at improving transient responses of the base linear systems. In addition, observer-based design is also considered. We prove that under some mild conditions, reset controller and observer can be designed separately. The obtained results are applied to short-span-seeking control of a kind of single stage hard disk drive servo systems. Simulations show that the proposed design is much more capable of improving transient response than traditional control design techniques. [Copyright &y& Elsevier]

Abstract: This paper considers the problem of the stabilization of affine nonlinear control systems. First, we assume that the systems under investigation are of the generalized Byrnes–Isidori normal form. A new way to approximate the center manifold is proposed, which can reduce the error degree of the center manifold approximation. A new matrix product, called the semi-tensor product, is introduced to obtain the approximation of the center manifold. Then the Lyapunov function with homogeneous derivative (LFHD) is used to design a stable center manifold by state feedback control. Finally, the method is applied to general affine nonlinear control systems. [Copyright &y& Elsevier]

In this paper, we investigate the asymptotical feedback controllability (AFC) of probabilistic logic control networks (PLCNs). First, the concept of asymptotical feedback reachability (AFR) is proposed, allowing us to define AFC. Then, we prove that a state is asymptotically feedback reachable if and only if (iff) it is a control fixed point, and there is an admissible path to it from any other state. Based on this, we prove that a PLCN is asymptotically feedback controllable iff every state is asymptotically feedback stabilizable. Moreover, we express the criteria for the AFR and AFC of PLCNs in terms of the reachability matrix, which are easily checkable. The relations between the AFC and other definitions of controllability are also discussed. Finally, an illustrative example is provided to show the usage of the proposed results and to demonstrate the design of feedbacks achieving transitions between states. [ABSTRACT FROM AUTHOR]

• Self-luminous bacteria were used as bifunctional probe for the simultaneous detection of multiple pathogens. • Self-luminous bacteria were prepared by co-culture of bacteria and organic fluorescent dyes. • The proposed method shows great potential for single colony detection by integrating with a pre-incubation step. Herein, we report a novel multiplex fluorescent competitive immunosensor using self-luminous bacteria as a bifunctional probe for the simultaneous detection and quantification of multiple pathogens. The self-luminous bacteria are prepared through the facile one-step co-culture of bacteria and organic fluorescent dyes. Cronobacter muytjensii , Listeria monocytogenes , and Escherichia coli O157:H7 are fluorescently labelled with 7-hydroxycoumarin, fluorescein isothiocyanate, and rhodamine B, respectively, due to the dyes small spectral overlap in excitation/emission. The obtained fluorescent bacteria retain specific immunorecognition activity, but exhibit excellent fluorescent sensing ability. By using these fluorescent bacteria as bifunctional probes for competitive recognition and optical sensing, we achieved the sensitive and simultaneous quantitative determination of three pathogens with sensitivities of below 8.6 × 103 CFU/mL. The sensitivities can be significantly enhanced to 1 CFU/mL in real milk by integrating with a pre-incubation step, showing great potential for the ultrasensitive determination of trace bacteria and even single colony with the overall detection time of less than 10 h. In summary, this work provides an alternative multiplexing analytical platform as a powerful and rapid diagnostic tool for monitoring foodborne pathogen contamination. [ABSTRACT FROM AUTHOR]

Ginsenoside Rg1 (Rg1) is traditional Chinese medicine with neuroprotective activity. Previous studies have demonstrated that Rg1 improves Alzheimer's disease (AD) and alters gut microbiology, but its mechanism remains to be elucidated, and thus far, its use in the treatment of AD has not been satisfactory. The present study investigated the improvement effects of Rg1 and its association with the microbiota of the large intestine. Following treatment with Rg1 in AD tree shrews, the treatment group demonstrated significantly shorter escape latency and crossed a platform more frequently in a water maze test. Western blotting demonstrated that Rg1 inhibited the expression of β-secretase 1, while increasing microtubule-associated protein 2 and Fox-3 in the hippocampus. Immunohistochemical analysis revealed that Rg1 decreased the expression of amyloid β, tau phosphorylated at serine 404 and pro-apoptotic factor Bax, while increasing the expression of Bcl-2 in the hippocampus and cortex. High throughput sequencing of 16S rRNA demonstrated that Rg1 altered the microbiota abundance of the large intestine. In conclusion, Rg1 affected the expression of apoptosis proteins, possessed a neuroprotective effect and may have a close association with the microbiota of large intestine by significantly reducing the abundance of Bacteroidetes and increasing the energy requirement of tree shrews. [ABSTRACT FROM AUTHOR]

Abnormal expression of long non-coding RNAs (lncRNAs) occurs in several diseases including renal fibrosis. Notably, growth arrest-specific 5 (Gas5) is a lncRNA, which functions as an essential modulator of cell proliferation and growth. However, the role and expression of lncRNA Gas5 associated with renal fibrosis remains controversial. Herein, we investigate the effect of lncRNA Gas5 deficiency in renal fibrosis induced by the operation of unilateral ureteric obstruction (UUO) in mice. Sera and urine of mice were used to detect markers of renal function. Further, Masson and immunohistochemical staining, western blotting as well as qRT-PCR were performed to observe the distribution and expression of fibrosis marker in the kidney tissue of the mice. Unlike the wild type mice, the obstructed kidney in Gas5+/− mice showed more severe renal fibrosis and collagen deposition. In the UUO-Gas5+/− group, the serum levels of uric acid, serum creatinine, and the urine levels of albumin-to-creatinine ratio were higher. Moreover, the expression of mRNA and protein of α-smooth muscle actin (α-SMA), vimentin, collagen IV, fibronectin, and matrix metalloproteinase 9 (MMP9) were higher, whereas that of phosphatase and tensin homolog (PTEN) were lower with the difference being statistically significant (p < 0.05). lncRNA Gas5 was up-regulated in renal fibrosis tissues, and its deficiency exacerbated renal fibrosis in the UUO mice model. [ABSTRACT FROM AUTHOR]

• A natural enzyme-free colorimetric immunoassay was developed for human chorionic gonadotropin detection. • AuNP@CTAB was first designed as a signal transducer to overcome the bottleneck of nanozyme activity loss. • The morphology-dependent catalytic properties of the three shaped AuNPs@CTAB were investigated. • Compared with traditional ELISA, the proposed method demonstrated similar detection sensitivities but was highly robust. The usage of nanozyme as label to establish immunoassays offers merits of low cost and high robustness. However, the catalytic activity of nanozyme is usually passivized by the modified layer of bio-recognition molecules. The peroxidase-mimicking activity of cetyltrimethylammonium bromide (CTAB)-coated gold nanoparticles (AuNPs@CTAB) is recovered by Ag+ ions. Herein, AuNPs@CTAB with Ag+-triggered catalytic activity was first designed as signal transducer to construct colorimetric immunoassay for human chorionic gonadotropin (HCG) detection. Silver nanoparticles were used as labels which can release numerous Ag+ ions by hydrogen peroxide corrosion and thus enhance the catalytic activity of AuNPs@CTAB. To achieve the highest detection sensitivity, we synthesized three kinds of AuNPs@CTAB with similar size but different shapes including nanospheres (AuNSs@CTAB), nanorods (AuNRs@CTAB), and nanocubes (AuNCs@CTAB). The morphology-dependent catalytic properties of AuNPs@CTAB were evaluated. Under optimum conditions, the proposed method using AuNSs@CTAB, AuNRs@CTAB and AuNCs@CTAB using AuNSs@CTAB, AuNRs@CTAB and AuNCs@CTAB gave LOD of 7.8, 15.6 and 31.2 mIU/mL, respectively. The developed immunoassays also showed good accuracy, high reproducibility and high robustness for detecting HCG in serum samples. In summary, the developed immunoassay is a promising bioanalysis platform which can provide similar sensitivity and enhanced robustness compared with traditional horse radish peroxidase-based immunoassays. [ABSTRACT FROM AUTHOR]

• The addition of metal oxide particles greatly improves the thermal conductivity of MPCS. • MPCS with metal oxide particles can enhance heat transfer under different flow conditions. • Heating power and flow rates are crucial to the heat transfer of MPCS. • MPCS with metal oxide particles can be used as heat transfer medium and energy storage fluid. ZnO, nano ZnO and nano Al 2 O 3 were mixed with microencapsulated phase change material slurry (MPCS) for improving the heat transfer performance of slurries in this paper. The thermal and rheological properties of MPCS were measured using DSC, thermal conductivity meter and rheometer. The results show that the thermal conductivity of 5 wt% MPCS with 1 wt% ZnO, nano ZnO and nano Al 2 O 3 was 17.9 %, 19.4 % and 23.5 % higher than that of 5 wt% MPCS, respectively. The forced convection heat transfer experiment of slurries was carried out in a loop system with various heat flux and flow conditions. The influences of heat flux, flow rate and metal oxide particles on the flow and heat transfer behaviour of slurries were investigated. The results show that the heat transfer was significantly enhanced for all slurries with metal oxide particles under three flow conditions. Compared with water, the local heat transfer coefficient (h x) of MPCSs with 1 wt% ZnO, nano ZnO and nano Al 2 O 3 increased by 6.5 %, 9.1 % and 12.4 % under laminar flow, 6.6 %, 15.5 % and 14.9 % under transition flow, and 15.7 %, 19.0 % and 21.6 % in turbulent condition, respectively. [ABSTRACT FROM AUTHOR]

The article presents a study which discusses mineral-geochemical analysis on the Danzhou tungsten-cesium polymetallic deposit in Hainan Province, China. Topics discussed include mineral geochemistry research approach, the microscopic investigation of mineral, mineralization characteristics of rubidium-cesium mineralized bodies, and discovery of tungsten-cesium polymetallic orebodies.

Background and Aims: The objective of this study was to construct and authenticate nomograms to project overall survival (OS) and cancer-specific survival (CSS) in primary gastrointestinal non-Hodgkin lymphomas (PGINHL). Methods: Suitable patients were chosen from the Surveillance, Epidemiology and End Results database and Wannan Medical College Yijishan Hospital. The Cox regression model was used to acquire independent predictive factors to develop nomograms for projecting OS and CSS. The performance of the nomograms was validated using the Harrell's concordance index (C-index), calibration curves, and decision curve analysis (DCA) and was compared with that of the AJCC 7th staging system. Survival curves were obtained using the Kaplan–Meier method, while the log-rank test was used to compare the difference among the groups. Results: The C-index of the nomograms for OS and CSS was 0.735 (95% CI = 0.719–0.751) and 0.761 (95% CI = 0.739–0.783), respectively, signifying substantial predictive accuracy. These outcomes were reproducible when the nomograms were used for the internal and external validation cohorts. Moreover, assessments of the C-index, AUC, and DCA between the nomogram results and the AJCC 7th staging system showed that the former was better for evaluation and was more clinically useful. Conclusions: We constructed the nomogram which could predict 1-, 3-, and 5-year OS and CSS of patients with PGINHL. Our nomogram showed good performance, suggesting that it can be used as an efficacious instrument for predictive assessment of patients with PGINHL. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a chronic neurodegenerative disorder that can cause cognitive impairment. Ginsenoside Rg1 (Rg1) has a significant neuroprotective effect on animals with memory impairment. However, the mechanism of how Rg1 mediates the Wnt signaling pathway and improves cognitive function by regulating oxidative stress, apoptosis, and neuroinflammation is still unclear. In this study, the spatial memory ability of tree shrews was tested by Morris water maze, the expression levels of amyloid protein (Aβ1‐42), ionized calcium‐binding adapter molecule 1 (iba‐1), nitrotyrosine (NT), and 8‐hydroxyguanine (8‐OHG) were detected by immunohistochemistry. Subsequently, the activity of catalase (CAT) and the glutathione peroxidase (GSH‐Px) was, respectively, measured by the ammonium molybdate method and the 5,5′‐dithiobis (2‐nitrobenzoic acid). Furthermore, the malondialdehyde (MDA) concentration was determined by the thiobarbituric acid test. Finally, the expression levels of Beta‐secretase (BACE1), superoxide dismutase (SOD), BCL2‐Associated X (Bax), B‐cell lymphoma‐2 (Bcl‐2), caspase‐anti‐apoptotic factor Cleaved‐caspase‐3 (Caspase‐3), microtubule‐associated proteins 2 (MAP2), Neuronal nuclear antigen (NeuN), as well as the phosphorylation of GSK‐3β and β‐catenin were detected by Western blot. This study implied that Rg1 reduced the phosphorylation of Tau protein, the deposition of Aβ1‐42, and the expression of BACE1. It also showed that Rg1 increased the antioxidant activity of SOD, CAT, GPx, and instead reduced the oxidation products of NT, 8‐OHG, and MDA, as wells as the inflammatory factor interleukin‐1 and iba‐1. It further showed that Rg1 increased the ratio of Bcl‐2 to Bax and expression of neuronal markers MAP2 and NeuN, but instead reduced the expression of Caspase‐3, GSK‐3β, and β‐catenin. In conclusion, by regulating the Wnt/GSK‐3β/β‐catenin signaling pathway, Rg1 of moderate and high dose could alleviate oxidative stress damage, improve neuroinflammation, protect neurons, finally improve the cognitive impairment of the AD tree shrew. This study provides theoretical basis for the Rg1 clinical application in AD. [ABSTRACT FROM AUTHOR]

The world is currently witnessing the spread of the deadly severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes the coronavirus disease 2019 (COVID-19). In less than three months since the first cases were reported, the World Health Organization declared it a pandemic disease. Although several treatment and prevention strategies are currently under investigation, a continuous effort to investigate and develop effective cures is urgently needed. Thus, we performed molecular docking and structure-based virtual screening of libraries of approved drugs, antivirals, inhibitors of protein-protein interactions, and one million other small molecules to identify strong binders of the SARS-CoV-2 receptor-binding domain (RBD) that might interfere with the receptor recognition process, so as to inhibit the viral cellular entry. According to our screening and selection criteria, three approved antivirals (elbasvir, grazoprevir, and sovaprevir) and 4 other drugs (hesperidin, pamaqueside, diosmin, and sitogluside) were identified as potent binders of the RBD. The binding of these molecules involved several RBD residues required for the interaction of the virus with its cellular receptor. Furthermore, this study also discussed the pharmacological action of the 4 non-antiviral drugs on hematological and neurological disorders that, in addition to inhibiting the viral entry, could be beneficial against the neurological disorders identified in COVID-19 patients. Besides, six other small-molecules were identified, with no pharmacological description so far, exhibiting strong binding affinities to the RBD that we believe worth being investigated as inhibitors of the SARS-CoV-2-receptor interaction. • We aimed to identify strong binders of the SARS-CoV-2 RBD to be used as inhibitors of virus-receptor interaction. • Accordingly, 3 antivirals, 4 other approved drugs and 6 small-molecules have been identified as potential ligands of the RBD. • The binding of these selected compounds involves several RBD residues crucial for the virus-receptor interaction. • Besides RBD-binding, we discussed the possible effects of the selected drugs on the COVID-19- related neurological disorders. [ABSTRACT FROM AUTHOR]

The article focuses on findings of a study on Characteristics of Fracture Lithofacies in Wenxipo W-Cs-RbPolymetallic Deposit, Hainan Province in China. Topics include relation of the enrichment of scheelite with tourmalinization and silicification; significance of discovery of tungsten deposit; relationships between fissure-fluid coupling and tungsten mineralization.

[Display omitted] • A pH-sensitive AIEgen was designed as biogenic amine-response indicators. • Under ammonia exposure, the acidified AIEgen (i.e. , H+ASQ) showed colorimetric and ratiometric fluorescence changes. • The designed H+ASQ-labeled paper chip can realize bimodal real-time monitoring of biological amines. • The paper chip can serve as a promising alternative strategy for food freshness evaluation. Existing single-signal-response fluorescent materials for biogenic amine detection have unsatisfactory detection performance. Herein, we developed a simple pH-sensitive aggregation-induced emission-active fluorogen (AIEgen) and demonstrated its potential for ratiometric monitoring of biogenic amines. This AIEgen, namely 4-(dimethylamino)styryl)quinoxalin-2(1 H)-one (ASQ), shows a typical donor (D)-acceptor (A) structure with nonmonotonic color and fluorescence responses to pH stimulation by its protonation/deprotonation on the D/A moieties. Subsequently, the H+ASQ-labeled paper chips were successfully prepared by physically depositing ASQ on qualitative filter paper, followed by the acidification by hydrochloric acid. Upon the exposure to ammonia vapour, the obtained H+ASQ-labeled paper chips exhibited obvious color and ratiometric fluorescence responses owing to the deprotonation of H+ASQ indicators, indicating that the proposed paper chips can be used for the detection of biological amines by bimodal colorimetry and ratiometric fluorescence. Under the optimal conditions, H+ASQ-labeled paper chip achieved the real-time, non-destructive, and visual monitoring of meat and seafood freshness by simultaneously quantify the biogenic amine index with high performance liquid chromatography (HPLC). The results of this work suggest that ratiometric AIEgen can serve as a promising alternative strategy to ensure accurate monitoring of biogenic amines and food freshness. [ABSTRACT FROM AUTHOR]

The ordered assembly of nanostructure is an effective strategy used to manipulate the hydrodynamic diameter (D H) of nanoparticles. Herein, a versatile dynamic light scattering (DLS) immunosensing platform is presented to sensitively detect small molecules and biomacromolecules by using the M13 phage as the building module to order the assembly of gold nanoflowers and gold-coated magnetic nanoparticles, respectively. After the directional assembly of M13 phage, the D H of the probes was significantly increased due to its larger filamentous structure, thus improving the detection sensitivity of the DLS immunosensor. The designed M13 assembled DLS immunosensor with competitive and sandwich formats showed high sensitivities for ochratoxin A and alpha-fetoprotein in real corn and undiluted serum samples, with the detection limits of 1.37 and 57 pg/mL, respectively. These values are approximately 15.8 and 164.9 times lower than those of traditional phage-based enzyme-linked immunosorbent assays. Collectively, this work provides a promising strategy to manipulate the D H of nanoparticles by highly evolved biomaterials such as engineered M13 phages and opens upon a new direction for developing DLS immunosensors to detect various targets by the fusion expression of special peptide or nanobody on the pIII or pVIII protein of M13 phage. [Display omitted] [ABSTRACT FROM AUTHOR]

The article focuses on findings of a study on mineral geochemical characteristics and indication significance of biotite -rutile in the gabbro intrusions in the yinmin iron-copper district, Yunnan, China. It states that the multiphase mineralization was intensively distributed in the Ti-Fe-rich gabbro intrusions, with uralitization, and biotitization, and mentions Mineral-geochemical characteristics such as Rutiles' symbiotic relationship with biotites.

[Display omitted] • A sulfydryl modification of M13 bacteriophage was used to enhance the sensitivity of colorimetric immunsensor. • The LOD value of the proposed method is 947-fold lower than that of HRP based ELISA method. • This novel signal amplification system can be extended for sensitive detection of other analytes by altering mimic peptide sequence. Herein, a sulfydryl modification of M13 bacteriophage was introduced as bio-functional component including biological recognition, and nanozyme container for enhancing sensitivity of colorimetric immunsensor, where the seven peptide sequence fused on the p3 protein of M13 was used to mimic deoxynivalenol (DON) antigen for recognizing the anti-DON monoclonal antibody, while the sulfydryl groups modified on capsid proteins were used to load numerous Ag coated Au nanoparticles (AuNPs@Ag) for improving the peroxidase-like activity of AuNPs@Ag. Owing its great loading capacity, the M13 bacteriophage assembled AuNPs@Ag nanocomposites (M13 DON @AuNPs@Ag) showed approximately 48- and 105-fold enhanced catalytic efficacy to hydrogen peroxide and tramethylbenzidine than those of natural horse radish peroxidase (HRP). Using the M13 DON @AuNP@Ag as signal amplifier, the proposed immunosensor exhibits a very high sensitivity for DON detection with the 50 % competitive inhibition concentration (IC 50) and detection limit (LOD) of 2.03 ng/mL and 13.67 pg/mL, respectively. These values are about 26- and 947-fold lower than those of conventional HRP based ELISA method (IC 50 and LOD values =52.43 ng/mL and 12.95 ng/mL, respectively). In addition, the proposed method also showed good specificity and accepted accuracy for DON detection in real corn samples. Moreover, the reliability of this novel strategy was further confirmed through compared with the high performance liquid chromatography method (HPLC). All in all, the M13 bacteriophage exhibits a promising potential as nanozyme container for enhancing the sensitivity of immunosensor, and this novel signal amplification system can be easily extended for highly sensitive detection of other analytes by altering specific mimic peptide sequence. [ABSTRACT FROM AUTHOR]

• Stimulus-responsive MOF@AuNP was designed as a low-background scattering signal probe. • Seed-mediated gold in situ growth strategy was used to amplify the scatting signal. • The proposed DLS immunosensor exhibited a high sensitivity for AFP detection with a LOD of 0.36 pg/mL. • The AuNP@MOF combined metal growth amplification showed a great potential for enhancing DLS signal. The ultrasensitive detection of disease-related biomarkers is critical to improving the early diagnosis, monitoring, and treatment of diseases. Herein, we reported a dynamic light scattering (DLS)-based immunosensor for the high-sensitivity detection of alpha-fetoprotein (AFP), an important biomarker in the early diagnosis of primary liver cancer. A metal–organic framework and gold nanoparticle composite (MOF@AuNP) was designed as a low-background scattering signal probe. After its structure was decomposed in a weak alkaline solution, the numerous small-sized AuNPs (∼4 nm) were released from the MOF structure. Controllable gold in situ growth strategy without self-nucleation was then executed to increase the AuNP size. Owing to the double signal amplification of the burst release of numerous small-sized AuNPs from MOFs and the gold in situ growth for an enhanced AuNP size, the proposed DLS immunosensor was successfully applied for the ultrasensitive detection of AFP with the detection limit of 0.36 pg mL−1. The reliability of the proposed method was evaluated by analyzing 22 actual clinic serum samples, and the results were further verified by the chemiluminescence immunosensor. This work features MOF@AuNP and the gold in situ growth amplified modulation of DLS-based signal transduction, which demonstrates the great potential as a novel bioanalytical platform for a myriad of purposes. [ABSTRACT FROM AUTHOR]

Ginsenoside Rg1 (GRg1) has neuroprotective effects on Alzheimer's disease (AD). The occurrence and progression of AD are closely related to gut microbiota. Few studies have learned the direct relationship between GRg1 and gut microbiota. In this study, we found an original way to research this relationship by using GRg1 in the AD model of tree shrews. Morris water maze and immunohistochemistry were performed to test the cognition repairing function of GRg1 by tree shrews and 16S ribosomal RNA sequencing was used to explore the composition and abundance of gut microbiota. After GRg1 treatment, the result of Morris water maze showed an improvement in cognitive function, and immunohistochemistry revealed a decrease in tau protein. Moreover, 16SrRNA sequencing results showed the abundances of Proteobacteria and Verrucomicrobia were significantly different, and Lactobacillaceae was significantly increased in the GRg1 treatment group. It also showed that the gut microbiome with middle and high doses of GRg1 was close to the normal group. In conclusion, this study suggests that GRg1 at middle and high doses may change the abundance of gut microbiota to improve AD, and that Proteobacteria and Verrucomicrobia are key microbiota. This is the first report that has ever studied the relationship between GRg1 and gut microbiota in tree shrews. [ABSTRACT FROM AUTHOR]