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In the high-load centrifugal compressor of near-critical CO 2 (NcCO 2) power-generation cycle, the overload of axial aerodynamic force causes significant harms to the structural safety and operational stability of turbomachinery components. Based on a transcritical CO 2 compressor of a MWt-class simple recuperated cycle, we numerically studied the aero-thermodynamic characteristics of back-cavity leakage, and discussed the physical model of the axial aerodynamic forces in off-design operation of NcCO 2 compressors. Finally, reduced-dimensional prediction method for the axial aerodynamic forces in the near-critical CO 2 compressor was developed. Wherein, the Japikse's method was used to estimate the primary aerodynamic loads of centrifugal impeller, and a 1-D radial equilibrium equation with angular velocity ratio was derived to predict the thrust force acting on the impeller back disk. Furtherly, based on the near-wall distribution pattern of angular velocities and physical property of Rankine vortex, a semi-empirical model of angular velocity ratio was introduced and completed the model of back-disk force. In validation, the reduced-dimensional prediction method exhibited satisfactory accuracy with perfectly acceptable errors compared to the refined CFD simulations. Thereby, a reduced-dimensional prediction method for the axial aerodynamic forces was developed for the economical and agile analysis of NcCO 2 compressors in engineering practices. • Numerical investigations on the internal flow in the near-critical CO 2 compressor. • Flow behaviors and aero-thermodynamic impacts of the back-cavity leakage flow. • Physical modeling of axial aerodynamic loads in the near-critical CO 2 compressor. • Reduced-dimensional prediction for axial aerodynamic forces in CO 2 compressors. [ABSTRACT FROM AUTHOR]

This paper studies the distributed attitude synchronization control for flexible spacecrafts with the consideration of unmeasurable modal variable and partial loss of actuator effectiveness faults. The designed rotation matrix-based controller consisted of the basic pattern and the supplementary pattern. Based on a connected undirected graph, the original graph was established on the assumption of inexistent actuator fault, and the unavailable flexible dynamics was approximately described by neural networks (NNs). By using the minimum learning parameter (MLP) algorithm, the finite-time stability of the formation system was improved and the burdensome computation was lightened. A modified sliding mode surface (SMC) is presented which can avoid singularity and the tracking errors can be stabilized to the equilibrium within finite time. • A finite-time attitude synchronization controller for flexible spacecrafts with unknown inertial parameters and actuator faults was proposed. • Actuator fault relation was described by undirected graph and the flexible dynamics was approximated by neural networks (NNs). • Computational complexity of finite-time controller was decreased by using MLP algorithm. [ABSTRACT FROM AUTHOR]

In the CO 2 power-generation cycles, the compressor inlet condition has significant impacts on the performances of turbomachinery as well as the economies of cycle systems. In this article, based on numerical simulation and system parametric analysis, we compared the subcritical and supercritical inlet conditions of the CO 2 compressor, which is from a prototype in a MWt simple recuperated cycle (SRC). As the result, the advantages and particularities of the subcritical inlet condition for the CO 2 compressor are discussed and confirmed from the aero/thermo-dynamics and thermal/technical economies. In the study, we found the efficiency and pressure ratios of the CO 2 compressor were significantly improved as the inlet pressure reduced below the critical point. And the operation of transcritical compression would not be obviously impacted by phase changes at the far-blockage conditions. In the system parametric analysis, we found the thermal and technical economies of the SRC system obtained significant rises at the subcritical compressor inlet condition. The increase of system efficiency reached 2–3%, while the financial cost reduced by 7.7%. The structural and mechanical safety of key components was also improved. Thereby, the present study provides different views to the benefits of subcritical compressor inlet conditions in CO 2 cycles. • Investigation and comparison of the multiple sub/super-critical working conditions. • Indicating the technical benefits of subcritical inlet conditions for CO 2 compressors. • Mechanisms for the performance improvement of CO 2 compressors. • System parametric modeling and analysis for the MWt CO 2 power generation cycle. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we consider a multi-sensor transmission power control problem in a remote state estimation scenario over a signal-to-noise-and-interference-based communication channel. Multiple sensors send their state measurement data to a remote estimator using a shared wireless communication channel. Since the transmission process of one sensor may be affected by the transmission power used by other sensors, all the sensors need to optimize their transmission strategies to achieve better performance. We formulate Markov decision process and Markov game frameworks to investigate the optimal transmission strategies for the sensors, develop several structural results on the optimal solutions, and then propose two heuristic transmission strategies for easier implementation. Simulation examples are provided to illustrate the main results. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A new subtype of lactate dehydrogenase is expressed from Schistosoma japonicum. • Enzymatic characteristics of the new lactate dehydrogenase. • Lactate dehydrogenase expression levels in male and female Schistosoma japonicum. • The new lactate dehydrogenase activity changes after antibody incubation. Abstract Lactate dehydrogenase (LDH) is a key enzyme in glycolysis process. It catalyzes the interconversion between pyruvic acid and lactic acid. Schistosoma japonicum adult worms largely rely on glycolysis for energy production when they parasitize in human. S. japonicum may be killed if energy production is suppressed. So, we wonder whether antibody against S. japonicum LDH is a harmful factor for S. japonicum surviving. In this study, we cloned and characterized S. japonicum lactate dehydrogenase B (SjLDHB) to evaluate its role in parasite survival. We found SjLDHB was highly similar to S. japonicum lactate dehydrogenase A (SjLDHA) which is another LDH subtype in S. japonicum in amino acid sequence. The optimal temperature of SjLDHB catalytic activity was 37 °C, the optimal pH values for pyruvate reduction and lactate oxidation were 7.0 and 6.0 and Km values of pyruvate and lactate were 0.2752 and 0.2339 mM respectively. Then, we identified SjLDHB expression in male and female S. japonicum. Finally, we evaluated the influence of antibodies on SjLDHB enzymatic activity. Interestingly, we found anti-SjLDHA antibody suppressed SjLDHB enzymatic activity, while anti-SjLDHB antibody and mixed antibody enhanced SjLDHB enzymatic activity in vitro. Although further investigation is needed, we suggest that anti-SjLDHB antibody may be not a negative factor, but a valuable compensation for S. japonicum adult worm surviving and pathogenicity. [ABSTRACT FROM AUTHOR]

Abstract In this work, a multi-sensor transmit power control design problem for remote state estimation over a packet-dropping network is investigated. In this problem, a remote estimator collects measurement innovations from each individual sensor node for data fusion, where the dropouts of data packets may occur over the communication network. Subject to an energy constraint, we propose a transmit power controller for each sensor based on a quadratic form of the measurements' incremental innovation. Under this specific form of transmit power controller which is proved to preserve the Gaussianity of the a posteriori state estimation, we derive the minimum mean squared error (MMSE) estimate for the remote state estimator with a closed-form recursion of the expected estimation error covariance. Performance analysis is also provided. For scalar systems, an upper bound of the expected estimation error variance is optimized subject to a limited energy budget over the parameters of the proposed power controller. Numerical comparisons with other controllers are made to illustrate the performance of our approach. [ABSTRACT FROM AUTHOR]

To deal with the issue of model uncertainty, extensive stochastic MPC methods have been investigated, where the uncertainties are typically assumed to follow given statistical distributions. However, in practical scenarios, the statistical properties of model uncertainties may depend on certain hyperparameters varying both temporally and spatially. For instance, in the applications of aero-engine control, different types of uncertainties may occur under different operational conditions, such as flight altitudes and Mach numbers, which are dynamically changing. Traditionally, the stochastic MPC methods may not be able to handle these types of uncertainties directly. Therefore, we propose a spatiotemporal learning-based stochastic model predictive control algorithm to study the stochastic optimal control problem with dynamically changing uncertainties, by constructing spatiotemporal Gaussian processes (GPs) to approximate the uncertainties based on measurement data. Since the spatiotemporal GPs may be difficult to evaluate with long processing time series, we present a state–space representation of GPs to employ computationally efficient Kalman filtering. Then, we derive a computationally tractable control strategy by parameterizing the controller and reformulating the cost and chance constraints, and analyze the corresponding recursive feasibility and closed-loop stability. Finally, the proposed algorithm is applied to the compressor control of the aero-engine, and the comparisons with other MPC controllers are demonstrated to show the effectiveness of our methods. [ABSTRACT FROM AUTHOR]

This paper considers a cyber-physical system (CPS) under denial-of-service (DoS) attacks. The measurements of a sensor are transmitted to a remote estimator over a multi-channel network, which may be congested by a malicious attacker. Among these multiple communication paths with different characteristics and properties at each time step, the sensor needs to choose a single channel for sending data packets while reducing the probability of being attacked. In the meanwhile, the attacker needs to decide the target channel to jam under an energy budget constraint. To model this interactive decision-making process between the two sides, we formulate a two-player zero-sum stochastic game framework. A Nash Q-learning algorithm is proposed to tackle the computation complexity when solving the optimal strategies for both players. Numerical examples are provided to illustrate the obtained results. [ABSTRACT FROM AUTHOR]

In this paper, we consider a security problem of remote state estimation in cyber–physical systems (CPS). The state measurements of a dynamic process, obtained by wireless sensors, may be modified deceptively by a malicious attacker, which may bypass a standard χ 2 detector. On the other hand, the estimation performance with a standard χ 2 detector typically is also difficult to analyze. As such, a stochastic detection mechanism with a varying triggering threshold is proposed. We provide an analytical performance evaluation for the estimation with the proposed detector, and propose a potential countermeasure to actively defend the deception attacks with the proposed detector. The interactive decision-making process between the system with the countermeasure and the attacker is then studied under a game-theoretic framework. In addition, we also extend the stochastic false data detection problem into a multi-sensor setting with a sequential data fusion process and more general attacking patterns, and analyze the estimation performance. Simulations are provided to illustrate the developed results. [ABSTRACT FROM AUTHOR]

Zearalenone (ZEA), a Fusarium mycotoxin that contaminates cereal crops worldwide, has been shown to affect the male reproductive system and trigger reactive oxygen species (ROS) generation. However, the mechanisms of its toxicity have not been fully understood. Because mitochondrion is a key organelle involved in producing ROS and generating metabolic intermediates for biosynthesis, an iTRAQ-based mitoproteomics approach was employed to identify the molecular mechanism of zearalenone toxicity using mitochondria of mouse Leydig tumor cells (MLTC-1). A total of 2014 nonredundant proteins were identified, among which 1401 proteins (69.56%) were overlapped. There were 52 differentially expressed proteins in response to ZEA, and they were primarily involved in energy metabolism, molecular transport and endocrine-related functions. Consistent with mitochondrial proteomic analysis, the ATP and intracellular Ca 2+ levels increased after ZEA treatment. The results suggest that lipid metabolism changed significantly after low-dose ZEA exposure, resulting in two alterations. One is the increase in energy production through promoted fatty acid uptake and β-oxidation, along with excessive oxidative stress; the other is an inhibition of steroidogenesis and esterification, possibly resulting in reduced hormone secretion. A hypothetical model of ZEA-induced mitochondrial damage is proposed to provide a framework for the mechanism of ZEA toxicity. [ABSTRACT FROM AUTHOR]

Two new copper bromide based coordination compounds 0D-Cu 2 Br 2 (3,5-dimethyl-pyridine) 4 (1) and 1D-Cu 2 Br 2 (5-bromo-pyrimidine) 2 (2) have been synthesized and exhibit potential as rare-earth metal free lighting phosphor alternatives. • Two new copper bromide based coordination compounds have been synthesized and structurally characterized. • The inorganic module of both compounds is Cu 2 Br 2 rhomboid dimer coordinated by the organic ligands. • Their luminescence properties have been studied. • Both compounds exhibit potential as rare-earth metal free lighting phosphor alternatives. Two new copper bromide based coordination compounds 0D-Cu 2 Br 2 (3,5-dimethyl-pyridine) 4 (1) and 1D-Cu 2 Br 2 (5-bromo-pyrimidine) 2 (2) have been synthesized and structurally characterized. X-ray diffraction analyses reveal that the inorganic module of both compounds is Cu 2 Br 2 rhomboid dimer coordinated by the organic ligands. Compound 1 is a zero-dimensional (0D) molecular complex while compound 2 is one-dimensional (1D) extended structure. Photoluminescence measurement results show that 1 emits green photoluminescence peaked at 520 nm, with an IQY of 82.4%. Compound 2 emits red photoluminescence peaked at 630 nm, with an IQY of 2.1%. Both compounds exhibit potential as rare-earth metal free lighting phosphor alternatives. [ABSTRACT FROM AUTHOR]

In this paper, we consider a secure problem in dynamic networks. A malicious attacker may attack the pinning controlled nodes and prevent the synchronization in the network. The network defender needs to secure the nodes with limited protective budget and increase the difficulties for launching attacks, while the attacker needs to decide the target nodes to attack. A resource allocation model for the defender and the malicious attacker is developed. A leader–follower Stackelberg game framework is proposed to study the behavior of both sides and the equilibrium of this security game is investigated. Numerical examples and simulations are presented to illustrate the main results. [ABSTRACT FROM AUTHOR]

This note is concerned with the stability analysis of linear systems with a time-varying delay, where the delay is assumed to be a periodically varying bounded function with restricted derivatives. Combining the allowable delay set (ADS) definition and the region partitioning technique, an ADS partitioning approach is proposed, and then by with aid of this approach, a novel Lyapunov–Krasovskii functional (LKF), namely delay-set-partition-based (DSPB) LKF, is developed. Compared with the previous LKF method, the main advantage of the DSPB LKF lies in allowing the considered system to construct its own LKF in each sub-ADS. By utilizing the proposed LKF, less conservative stability criteria are derived. Finally, two simulation examples are provided to verify the effectiveness and superiority of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, the attack detection problem is investigated for cyber–physical systems (CPSs) with unknown-but-bounded (UBB) noises. A new hybrid proactive detection scheme is proposed to detect stealthy attacks by combining watermarking and moving target (MT). The designed abnormal detector is based on the residual of the zonotopic observer which can be utilized to estimate states of the system with UBB noises. We prove that the approach proposed in this work does not introduce any performance loss in the absence of attacks. The proposed active detection framework can be employed to detect various types of attacks, such as denial-of-service (DoS), replay and covert attacks. Finally, numerical examples are provided to demonstrate the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

Hypothyroidism is commonly detected in patients with medulloblastoma (MB). However, whether thyroid hormone (TH) contributes to MB pathogenicity remains undetermined. Here, we find that TH plays a critical role in promoting tumor cell differentiation. Reduction in TH levels frees the TH receptor, TRα1, to bind to EZH2 and repress expression of NeuroD1, a transcription factor that drives tumor cell differentiation. Increased TH reverses EZH2-mediated repression of NeuroD1 by abrogating the binding of EZH2 and TRα1, thereby stimulating tumor cell differentiation and reducing MB growth. Importantly, TH-induced differentiation of tumor cells is not restricted by the molecular subgroup of MB, suggesting that TH can be used to broadly treat MB subgroups. These findings establish an unprecedented association between TH signaling and MB pathogenicity, providing solid evidence for TH as a promising modality for MB treatment. [Display omitted] • T3 induces terminal differentiation of MB tumor cells through upregulating NeuroD1 • T3 promotes NeuroD1 transcription by interfering with TRα1 and EZH2 interaction • T3 represses the growth of human and mouse tumors from multiple MB groups • T3-induced differentiation is an effective and safe strategy for MB treatment Yang et al. reveal the mechanisms underlying the terminal differentiation of tumor cells in medulloblastoma (MB) and establish an unprecedent connection between thyroid hormone (TH) signaling and MB progression. These studies provide evidence that TH represents a promising approach for MB treatment through promoting tumor cell differentiation. [ABSTRACT FROM AUTHOR]

Low-temperature seawater is far away from CO 2 critical temperature, which has significant impacts on the performance of CO 2 closed cycle in the marine environment. The temperature adaptability of CO 2 closed cycle to the marine environment and its performance remain open issues. In this paper, we compare performance advantages of transcritical/supercritical CO 2 cycle based on thermodynamic and dynamic models. Compared with supercritical CO 2 Brayton cycle, transcritical gas-phase CO 2 Brayton cycle exhibits higher thermal efficiency and specific power at low cycle maximum pressure, and its reduced heat load and thermal inertia of regenerator facilitate cycle rapid response. However, transcritical liquid-phase CO 2 Brayton cycle and transcritical CO 2 Rankine cycle demonstrate higher thermal efficiency and specific power at high cycle maximum pressure. Lower compressor inlet temperature causes CO 2 pseudo-critical point to migrate into regenerator, and the intersection point of c p curves of CO 2 on both sides is located within regenerator. This can lead to pinch point and non-physical design within regenerator that inhibits cycle response. It can be avoided by adjusting cycle matching parameters so that the temperature corresponding to intersection point is lower than regenerator hot side outlet temperature. This study provides insights into performance advantages of transcritical CO 2 cycles in marine environments. [Display omitted] • Compare the performance of trans/supercritical CO 2 cycles in marine environments. • Performance analysis based on the cycle thermodynamic and dynamic simulation model. • Transcritical CO 2 cycle performance is more advantageous in marine environments. • Migration of pseudo-critical point to regenerator can inhibit the cycle response. • Avoid pseudo-critical point migration by adjusting cycle matching parameters. [ABSTRACT FROM AUTHOR]

Abstract: A new protocol for the synthesis of a variety of 2-aminobenzimidazole derivatives has been developed. O-haloaryl carbonimidoyl dichloride reacted with anilines to generate an o-haloaryl guanidine intermediate, which underwent copper catalyzed ring closure to afford 2-aminobenzimidazole derivative in moderate yields [Copyright &y& Elsevier]

In this paper, we consider optimal linear sensor fusion for obtaining a remote state estimate of a linear process based on the sensor data transmitted over lossy channels. There is no local observability guarantee for any of the sensors. It is assumed that the state of the linear process is collectively observable. We transform the problem of finding the optimal linear sensor fusion coefficients as a convex optimization problem which can be efficiently solved. Moreover, the closed-form expression is also derived for the optimal coefficients. Simulation results are presented to illustrate the performance of the developed algorithm. [ABSTRACT FROM AUTHOR]

• The annual water retention capacity was 1058.89 × 108 m3. • Grazing pressure index was higher for summer pasture than for winter pasture. • Grazing pressure negatively impacts on water yield. • Grazing exhibits different effects on the water yield of various grassland types. Known as the "Chinese water tower," the Three River Headwaters (TRH) region serves an important water retention function. In addition, grassland in this region is mainly used for grazing. However, grazing pressure potentially threatens the balance of this alpine grassland ecosystem. Thus, the influence of grazing activity on water retention needs to be explored. Based on remote sensing, meteorological, government statistics, hydrological records, and field observation data, we used the Integrated Valuation of Environmental Services and Tradeoffs model, grazing pressure index (GPI), and regression analysis to assess water yield (WY) variations and investigate the influence of grazing activity on water retention. The results showed that the grasslands were overloaded in the southern and eastern areas, whereas they had the capacity to carry more livestock in the western and central areas. Grazing pressure negatively impacts on WY in most of the TRH region. Source regions of the Yangtze, Yellow, and Lantsang Rivers also exhibited significant negative correlations between GPI and WY. Grazing decreased the soil water content in the alpine steppe, alpine meadow, and temperate steppe sites at soil depths of 0–30 cm, and a significant decrease was observed in the alpine meadow site at a depth of 10–20 cm. In all the areas, WY tended to decrease with GPI. Regression analyses indicate that GPI could better explain the total WY variation in the alpine meadow than in temperate steppe and alpine steppe. This implies that grazing activity has a negative effect on water retention, particularly in alpine meadows. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA) is a mycotoxin ubiquitous in feeds and foodstuffs. The water-insoluble pentacyclic triterpene bioactive compound, ursolic acid (UA), is widespread in various cuticular waxes of edible fruits, food materials, and medicinal plants. Although studies have reported that oxidative stress was involved in both the nephrotoxicity of OTA and the renoprotective function of UA, the role of stress-responsive Lon protease 1 (Lonp1) in the renoprotection of UA against OTA is still unknown. In this study, cell viability, reactive oxygen species (ROS) production, and several proteins' expressions of human embryonic kidney 293T (HEK293T) cells in response to UA, OTA, and/or Lonp1 inhibitor CDDO-me treatment were detected to reveal the protective mechanism of UA against OTA-induced renal cytotoxicity. Results indicated that a 2 h-treatment of 1 μM UA could significantly alleviate the ROS production and cell death induced by a 24 h-treatment of 8 μM OTA in HEK293T cells (P < 0.05). Compared with the control, the protein expressions of Lonp1, Aco2 and Hsp75 were significantly inhibited after 8 μM OTA treating for 24 h (P < 0.05), which could be notably reversed by the pre-treatment and post-treatment of 1 μM UA (P < 0.05). The protein expressions of Lonp1, Aco2 and Hsp75 were inhibited by the addition of CDDO-me. The three protein expression trends were similar before and after the addition of CDDO-me. In conclusion, OTA could inhibit the expression of Lonp1, suppressing Aco2 and Hsp75 as a result, thereby activating ROS and inducing cell death in HEK293T cells, which could be alleviated by UA pre-treatment. Image 1 • The 1 μM ursolic acid (UA) could alleviate 8 μM ochratoxin A (OTA) nephrotoxicity. • The 1 μM UA could alleviate 8 μM OTA-induced ROS production. • Ameliorative effect of UA on OTA nephrotoxicity was mediated by Lonp1/Aco2/Hsp75. [ABSTRACT FROM AUTHOR]

Abstract Soil organic carbon (SOC) plays an important role in global carbon cycling and is increasingly important to the ecosystem. An accurate SOC content map would significantly contribute to the proper application of ecological modeling. Therefore, there is a need to accurately estimate and map SOC content in grasslands. We evaluated various methods for estimating the SOC content of grasslands using field soil sampling data and auxiliary data in the pastoral area. The results showed that (1) SOC is affected by various factors, including geographic location, soil, topography, and climate. Single-variable SOC models account for 2%–72% of the variations in the grassland SOC. (2) Based on the correlation of environmental variables of SOC, normalized difference vegetation index, annual precipitation, annual average temperature, elevation, and moisture index were explored as critical auxiliary data to predict SOC content. We established multi-factor weighted regression model (MWRM). (3) We compared three spatial estimation methods, including inverse distance weighting, regression kriging, and MWRM, to determine a suitable method for SOC mapping. Our results indicate that among the three spatial estimation methods, MWRM provides the lowest prediction error (RMSE = 4.85 g/kg; MAE = 3.47 g/kg; MRE = 24.04%) and highest R 2 (0.89) and Lin's concordance (0.94) values in the spatial estimation at a 0–10 cm soil layer. (4) Therefore, we applied MWRM to predict SOC content at various layers, and its SOC content prediction in the topsoil (0–20 cm) is better than that in the subsurface (20–30 cm) and subsoil (30–40 cm). The SOC content spatial distribution demonstrated a similar pattern for each soil layer and the SOC content gradually decreased with increasing soil depth. Highlights • Single-variable models only reflect 2%–72% of the variation in SOC. • MWRM to analyze the spatial distribution of SOC is more accurate than IDW and RK. • MWRM shows the highest accuracy in the 0–10 cm soil layer. • The SOC content decreasing gradually with increasing depth [ABSTRACT FROM AUTHOR]

Soil erosion caused by wind is a serious environmental problem that results in land degradation and threatens sustainable development. Accurately evaluating wind erosion dynamics is important for reducing the hazard of wind erosion. Separating the climatic and anthropogenic causes of wind erosion can improve the understanding of its driving mechanisms. Based on meteorological, remote sensing and field observation data, we applied the Revised Wind Erosion Equation (RWEQ) to simulate wind erosion in Inner Mongolia, China from 1990 to 2015. We used the variable control method by input of the average climate conditions to calculate human-induced wind erosion. The difference between natural wind erosion and human-induced wind erosion was determined to assess the effect of climate change on wind erosion. The results showed that the wind erosion modulus had a remarkable decline with a slope of 52.23 t/km 2 /a from 1990 to 2015. During 26 years, the average wind erosion for Inner Mongolia amounted to 63.32 billion tons. Wind erosion showed an overall significant decline of 49.23% and the partial severer erosion hazard significantly increased by 7.11%. Of the significant regional decline, 40.72% was caused by climate changes, and 8.51% was attributed to ecological restoration programs. For the significant regional increases of wind erosion, 4.29% was attributed to climate changes and 2.82% to human activities, mainly overgrazing and land use/cover changes. During the study, the driving forces in Inner Mongolia of wind erosion dynamics differed spatially. Timely monitoring based on multi-source data and highlighting the importance of positive human activities by increasing vegetation coverage for deserts, reducing grazing pressure on grasslands, establishing forests as windbreaks and optimizing crop planting rotations of farmlands can all act to reduce and control wind erosion. [ABSTRACT FROM AUTHOR]

Transport expansion is detrimental to natural ecosystems and yet to what extent it can impact nearby alpine ecosystems is not well understood. This case study in Qinghai–Tibet railway and highway explores the biophysical effects of transport infrastructure in terms of remote sensing-based greenness, wetness, dryness, and heat according to a space-for-time substitution method. We estimate highly diverse changes across road sections in all the indices from both multiyear-mean and long-term perspectives, and no clear biophysical gradients with distance away from the transport lines, except for a gradual decrease in multiyear-mean heat and wetness. In a 500-m buffer zone, those indices on average are 0.1–15.7% lower or higher than the references and the disparities increase or decrease significantly from 2000 to 2021 alongside 15–48% of the transport lines. We further find that the estimated biophysical changes depend strongly on the reference conditions and the elevation gradients nearby the roads. Also, the road sections surrounded by some urban/crop lands show much more frequent "significant" trends than the others, confirming strong land use effects on the biophysical dynamics in alpine regions. Nevertheless, it remains open to debate to what extent transportation contribute the land use activities near the roads. We argue that highways and railways unlikely strongly impact the biophysical conditions in alpine regions due to small road width, widespread nature reserves, various protective measures, and low accessibility to surroundings if they are fenced. Our results highlight the small biophysical impacts of transport infrastructure on roadside natural ecosystems in the Qinghai-Tibet Plateau and suggest prioritized attention to the direct damages to soil and vegetation by transport construction and the habitat disruption, biodiversity change, and road kills by transport operation for developing an environment-friendly transport system. [Display omitted] • Multiyear mean and long-term biophysical effects were quantified in alpine regions. • All indices show highly diverse changes across buffer zones and road sections. • No clear biophysical gradients with rising distances away from the transport lines. • Strong impacts of elevation, climate, and the other concurrent land use activities. • The direct damages and other ecological elements deserve more attention. [ABSTRACT FROM AUTHOR]

This paper considers the design issue of optimal integrity attacks on remote estimation with multiple information sources in cyber–physical systems. The specific scenario is that the smart sensors transmit innovations via a wireless network to the remote estimator. There are two types of sensors—safe and suspicious ones, where the innovations of safe sensors have no possibility of being modified by a malicious attacker, but the innovations from suspicious sensors may be intercepted and modified. The typical integrity attacks focus on utilizing the innovations of suspicious sensors and current innovations, which underutilize the available information that limits the impact on remote estimation and may be exposed under mutual verification between safe and suspicious sensors. Consequently, we propose a stealthy integrity attack with a finite horizon of historical data from both types of sensors, i.e., the so-called integrity attack with spatial–temporal information sources, which further enhances the effectiveness of integrity attacks. The stealthiness constraints and the corresponding estimation error covariances under the proposed attacks are obtained. The analytical expressions of optimal integrity attack strategies are derived by maximizing the estimation error under stealthiness constraints. In addition, we investigate the properties of the optimal integrity attack strategies when the attacks occur consecutively. Finally, some numerical simulations are presented to demonstrate the effectiveness of the obtained results. [ABSTRACT FROM AUTHOR]

Networked control systems have unique advantages, but it might suffer from attacks, and the resulting asynchronous switching will greatly degrade the system performance and increase the difficulty of controller design. To address this challenge, in this paper, a new switching law and a resilient adaptive event-triggering strategy (RA-ETS) are proposed for networked switched systems to mitigate the negative impacts of asynchronous switching and denial of service (DoS) attacks By utilizing the new switching law, asynchronous switching is converted to expected and unexpected synchronous switchings. According to the minimum DoS sleeping time, the constraints on average dwell time and minimum dwell time are obtained for this switching law, and the sufficient conditions for the existence of expected synchronization are derived. Moreover, RA-ETS is designed to prevent the useless data during attacking from being triggered and to adjust the triggering frequency adaptively if no attacks. Subsequently, the stability of switched systems with an H ∞ performance index is ensured by virtue of the average dwell time method and piecewise Lyapunov–Krasovskii functional technique. In particular, the coupling relationship among the DoS attacking, expected and unexpected synchronous intervals is revealed. Finally, the effectiveness of the proposed approach is illustrated by a numerical simulation. [ABSTRACT FROM AUTHOR]

With the booming development of electric vehicles (EVs), the problem of managing a large number of EVs with frequent energy requirements due to limited batteries capacity has attracted more and more attention. It thus is significantly important to design an efficient energy supplement scheduling scheme. Due to the long charging waiting duration of the plug-in charging strategy, we introduce the battery swapping mechanism in this paper, which can considerably reduce the time of energy refill from hours to minutes. For the depleted batteries from EVs, we leverage a two-period charging with constant current-constant voltage (CC-CV) to model the recharging process. The CC-CV model depicts the characteristic of the battery during the practical charging scenario and is widely used for Li-ion battery charging. The battery degradation cost is further formulated to capture the performance degradation for the depleted batteries causing by charging. Considering the focus from EV drivers on waiting time of battery swapping service, and that from the operator on battery degradation cost, a demand balance battery swapping service framework is thus proposed. Moreover, a reservation-enabled scheme is designed to predicate swapping waiting time by capturing EV's reservations. Therefore, the demand balance can be eventually achieved by jointly optimizing waiting time and battery degradation cost. Simulations present the desirable performance of the proposed scheme with the comparison of other benchmarks. Particularly, the degradation of batteries is well alleviated, which is vital for BSSs' long-term operation. • Battery charging management based on the constant current-constant voltage model. • Calculation of the battery degradation cost according to the charging model. • Prediction of the service waiting time for EV drivers. • A reservations-enabled demand balance battery swapping service management framework. • Reduction of battery degradation while maintaining high-level QoE. [ABSTRACT FROM AUTHOR]

Abstract: Lactate dehydrogenase (LDH), a terminal glycolytic enzyme, is generally considered as a cytosolic protein. We cloned lactate dehydrogenase from Echinococcus granulosus (EgLDH) and predicted it may be a membrane protein with two transmembrane regions through bioinformatics analysis. Intact worm immunofluorescence with antibodies prepared against linear B cell epitopes predicted in the region inside or outside of the membrane demonstrated that EgLDH spans the tegumental membrane twice, with the N terminal and C terminal all outside, just consistent with the putative topological structure. Then, the enzymatic characteristics and kinetic parameters of recombinant EgLDH were surveyed and the results suggested that EgLDH is responsible for catalyzing the reduction of pyruvic acid into lactic acid under physiological conditions. The enzymatic activity of the recombinant protein was inhibited by antibodies directed against the intact protein or against epitopes that contain key residues in the catalytic center or substrate binding sites. EgLDH is a potential target for drugs and vaccines against E. granulosus. [Copyright &y& Elsevier]