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With the application of new technologies in vehicles such as wireless communications, microelectronics, Artificial Intelligence (AI) and Autonomous Vehicles (AV), there are lots of embedded hardware and software in vehicles, and so cryptographic technologies such as block ciphers are also applied to the vehicle system to protect its security and privacy. In order to better find potential security vulnerabilities and improve security of the vehicle system which applied SIMON block cipher, in this paper, a novel Differential fault attack (DFA) method is presented. By inducing a random bit fault in $L^{T-4}$ (the fourth round from the last), we first demonstrate the process of identifying the fault-induced position. Then, on the basis of the determined position, we describe how to retrieve three rounds of keys by inducing only one round of faults. For retrieving the SIMON family, compared with previous DFAs under the random bit fault model, the lowest numbers of fault-induced and fault locations (or rounds) are required by our attack. In particular, when the key words $m$ is 2 or 3, the proposed attack only needs to induce one round of faults. Finally, we carry out simulation verification and a comparison to illustrate the correctness and effectiveness of the proposed attack.

In order to make turns, a fixed-wing unmanned aerial vehicle (UAV) needs to change its bank angle gradually. While banking at large angle and high velocity leads to an increased risk of stalling the aircraft. It means that there exists a bank angle constraint (BAC) for a flying UAV. However, BAC is often ignored in studies regarding a fixed-wing UAV assisted communications. This letter considers a fixed-wing UAV assisted full-duplex amplify-and-forward relaying with a BAC, where the UAV is flying along a circular path while forwarding a required amount of data-bits from a source to a destination. With the aim of minimizing the energy consumption, a joint optimization scheme for adjusting the UAV’s flight velocity, radius and time is developed. The effectiveness and efficiency of the proposed joint optimization scheme as well as the impact of the BAC on the optimization scheme are verified by computer simulations.

This paper solves an energy-efficient optimization problem of a fixed-wing unmanned aerial vehicle (UAV) assisted full-duplex mobile relaying in maritime communication environments. Taking the speed and the acceleration of the UAV and the information-causality constraints into consideration, the energy-efficiency of the system under investigation is maximized by jointly optimizing the UAV's trajectory and the individual transmit power levels of the source and the UAV relay nodes. The optimization problem is non-convex and thus cannot be solved directly. Therefore, it is decoupled into two subproblems. One sub-problem is for the transmit power control at the source and the UAV relay nodes, and the other aims at optimizing the UAV's flight trajectory. By using the Lagrangian dual and Dinkelbach methods, the two sub-problems are solved, leading to an iterative algorithm for the joint design of transmit power control and trajectory optimization. Computer simulations demonstrated that by conducting the proposed algorithm, the flight trajectory of the UAV and the individual transmit power levels of the nodes can be flexibly adjusted according to the system conditions, and the proposed algorithm can achieve significantly higher energy efficiency as compared with the other benchmark schemes.

This paper studies a fixed-wing unmanned aerial vehicle (UAV) assisted mobile relaying network (FUAVMRN), where a fixed-wing UAV employs an out-band full-duplex relaying fashion to serve a ground source-destination pair. It is confirmed that for a FUAVMRN, straight path is not suitable for the case that a huge amount of data need to be delivered, while circular path may lead to low throughput if the distance of ground source-destination pair is large. Thus, a running-track path (RTP) design problem is investigated for the FUAVMRN with the goal of energy minimization. By dividing an RTP into two straight and two semicircular paths, the total energy consumption of the UAV and the total amount of data transferred from the ground source to the ground destination via the UAV relay are calculated. According to the framework of Deep Reinforcement Learning and taking the UAV's roll-angle limit into consideration, the RTP design problem is formulated as a Markov Decision Process problem, giving the state and action spaces in addition to the policy and reward functions. In order for the UAV relay to obtain the control policy, Deep Deterministic Policy Gradient (DDPG) is used to solve the path design problem, leading to a DDPG based algorithm for the RTP design. Computer simulations are performed and the results show that the DDPG based algorithm always converges when the number of training iterations is around 500, and compared with the circular and straight paths, the proposed RTP design can save at least 12.13 % of energy and 65.93 % of flight time when the ground source and the ground destination are located 2000 m apart and need to transfer 5000bit/Hzof data. Moreover, it is more practical and efficient in terms of energy saving compared with the Deep Q Network based design.

This paper studies a full-duplex (FD) amplify-and-forward relaying, where a fixed-wing unmanned aerial vehicle (UAV) is dispatched as a mobile relay to serve a source-destination communication pair so as to satisfy their service requirement. Here, the UAV relay flies in a circular path and hence it must continuously change its heading of flight which leads to a bank angle of the aircraft. In order to ensure flight safety, therefore, a bank angle limit is imposed on the UAV relay. By considering a practical FD relaying, namely, there exists both residual loop interference (RLI) and processing time-delay at the relay side, novel signal to interference plus noise ratio (SINR) received at the destination is analyzed, giving a closed-form expression in addition to a concise lower-bound. Armed with the SINR analysis, the size of data received by the destination during a period of flight time of the UAV is calculated, leading to a closed-form lower-bound of the size of data. Taking bank angle limit into consideration and using the calculated lower-bound of the size of data, an optimization problem with the purpose of energy conservation is solved, leading to a novel method for joint adjustment of the UAV's flight parameters. Computer simulation experiments are conducted, and the results demonstrated that the proposed optimization method performs better in terms of energy conservation compared to the benchmark techniques regardless of the value of RLI and/or the service requirement of the source-destination communication pair.

The socio-ecological environmental problem caused by the development of coalbed methane (CBM) is becoming more serious, so it is very significant for accelerating the development of CBM industrialization to identify the main influential factors of socioecological environmental risks and take effective risk prevention measures. Based on the triangular fuzzy number method, this paper firstly establishes a comprehensive correlation matrix. Then, the affected factors of socio-ecological environmental risks are analyzed by the DEMATEL method during the development of CBM. Then according to the aspects of centrality and causality, the key indicators are determined. Furthermore, the scenario simulation based on the FCM, the steady-state value and the comprehensive importance of key indicators, and the core indicators are selected. Finally, the scenario simulation of risk management countermeasure is done. The results show that: ① The index weights are calculated by the triangular fuzzy numbers, and the correlation matrix in DEMATEL is obtained by the weight ratio, which reduces the shortcomings and the subjectivity of traditional DEMATEL method. ② The correlation matrix in FCM is established based on the comprehensive correlation matrix in the above improved DEMATEL, which not only makes the FCM model more comprehensive and reduces the difficulty that the FCM correlation matrix is obtained considering the indirect influence relationship between indicators, but also makes up for the disadvantages that DEMATEL excludes during the selection of the core indexes, which are the considerations of the dynamic change of the importance of the indicators. ③ The rate of forestry and grass coverage, the ratio of investment in prevention and construction, the pollution index of soil Merlot, the reliability of machinery and equipment, the standard evaluation index of major pollution factors of underground water, and the ability of personal risk prevention are the key indicators, in which the rate of forestry and grass coverage, the ratio of investment in prevention and construction, and the reliability of machinery and equipment are the core indicators and are extremely important for the management of socio-ecological environmental risks during the development of coalbed methane. ④ The results of the scenario simulation of risk management countermeasure show that the core variables affect the socio-ecological environmental risks through such indicators as the degree of production mechanization, the degree of demolition and resettlement, and the ratio of economic loss by the influenced mechanism analysis; the ratio of investment in prevention and construction has the greatest impact on the socio-ecological environment risks in the early stage of CMB development, while the rate of forestry and grass coverage is the most important in the middle and late stages by the influenced result analysis. Therefore, this paper puts forward some corresponding stage suggestions on the prevention and control of socio-ecological environmental risks during the CMB development. In the early stage of CMB development, the ratio of investment in prevention and construction should be increased. In the middle stage, it is very important to reduce the damage of vegetation regions and to improve the reliability of machinery and equipment; in the late stage, the investment in prevention and construction should be increased steadily and the recovery of damaged vegetation areas should be focused on.

This paper investigates an in-band full-duplex (IBFD) relaying, where a fixed-wing unmanned aerial vehicle (UAV) is dispatched as an amplify-and-forward relay to forward data from a source to a destination. By considering ideal and practical IBFD cases, new received signal-to-noise ratio (SNR) expressions at the destination are derived. Armed with the newly derived SNR expressions and the existing one in literature, three different lower-bounds of the size of data received by the destination are calculated. Using the three lower-bounds of the size of data, an optimization problem corresponding to energy minimization of the IBFD relaying system subject to a total data-bit constraint in addition to a mission completion time (MCT) constraint is solved, leading to three sets of solutions. Computer simulation experiments are conducted and the accuracy of the derived SNR expressions and the three sets of solutions of the optimization problem are compared. The results demonstrated that the newly derived SNR expressions are more accurate than the existing one in literature and are more suitable to be utilized for energy minimization, and the proposed optimization method can complete the relaying task with the minimum energy and MCT. When the residual loop-interference channel power is equal to -100dB, the scheme of ideal IBFD only consumes up to 2.5% of the energy of the compared schemes regardless of the value of the total data-bit constraint.

The monoamine neurotransmitter serotonin (5-hydroxytryptamine; 5-HT) exerts an inhibitory influence over motivation, but the circuits mediating this are unknown. Here, we used an optogenetic approach to isolate the contribution of dorsal raphe nucleus (DRN) 5-HT neurons and 5-HT innervation of the mesolimbic dopamine (DA) system to motivated behavior in mice. We found that optogenetic stimulation of DRN 5-HT neurons enhanced downstream 5-HT release, but this was not sufficient to inhibit operant responding for saccharin, a measure of motivated behavior. However, combining optogenetic stimulation of DRN 5-HT neurons with a low dose of the selective serotonin reuptake inhibitor (SSRI) citalopram synergistically reduced operant responding. We then examined whether these effects could be recapitulated if optogenetic stimulation specifically targeted 5-HT terminals in the ventral tegmental area (VTA) or nucleus accumbens (NAc) of the mesolimbic DA system. Optogenetic stimulation of 5-HT input to the VTA combined with citalopram treatment produced a synergistic decrease in responding for saccharin, resembling the changes produced by targeting 5-HT neurons in the DRN. However, this effect was not observed when optogenetic stimulation targeted 5-HT terminals in the NAc. Taken together, these results suggest that DRN 5-HT neurons exert an inhibitory influence over operant responding for reward through a direct interaction with the mesolimbic DA system at the level of the VTA. These studies support an oppositional interaction between 5-HT and DA systems in controlling motivation and goal-directed behavior, and have important implications for the development and refinement of treatment strategies for psychiatric disorders such as depression and addiction.

Although graphitic carbon nitride (g-C3N4) is frequently mentioned as an environmentally friendly and low-cost photocatalyst, its photocatalytic efficiency is severely constrained by its greater band gap and easy recombination of photogenerated carriers. Introducing nitrogen defects into the photocatalyst can effectively improve the photocatalytic efficiency of g-C3N4. As the position and concentration of inserted nitrogen defects are important factors affecting the catalytic performance of g-C3N4, this review summarized the synthesis methods developed in recent years based on the perspective of the regulation of nitrogen defect position and concentration. Additionally, this study provided an overview of the characterization methods for discovering nitrogen defects and accurately identifying their exact positions in g-C3N4. At the same time, the mechanism of nitrogen defects promoting the photocatalytic performance of g-C3N4was explored from aspects such as enhancing light absorption, promoting the transfer and separation of photogenerated carriers, and increasing the consumption of photogenerated carriers through surface reactions. Finally, the opportunities and challenges of nitrogen defects in identification, synthesis, and mechanism of action were discussed.

Microcystin pollution of the environment is a prevalent problem that has gained considerable attention in sustainable development. Photocatalytic degradation is one of the most efficient ways to address this environmental issue. In this study, a porous C3N5carbon nitride nanosheet (NCN) with high photocatalytic activity was prepared using 3-amino-1,2,4-triazole as the raw material by a simple and environmentally friendly stepwise pyrolysis technique. The morphology, microstructure, chemical composition, and optoelectronic properties of the materials were analyzed by characterization (SEM, TEM, XRD, FI-IR, XPS, UV–vis, PL, Etc.). The specific surface area and charge mobility of NCN were both increased by the porous structure. The specific surface area of NCN was 4.95 times greater than that of CN-650, and it has a narrower band gap and a broader visible absorption range. The degradation rate of microcystin-LR by NCN, driven by visible light, reached 99.99% at 45 min, and the degradation kinetic constant was 9.09 times that of its precursor. Singlet oxygen (1O2) plays the most crucial role in the photocatalytic degradation of MC-LR by NCN. In addition, possible degradation pathways were sought by studying the intermediates of the MC-LR photodegradation process. The NCN photocatalysts developed in this work provide a wide range of possibilities for photocatalyst design and the mechanistic analysis of photocatalytic degradation of microcystins.

Converging lines of behavioral, electrophysiological, and biochemical evidence suggest that 5-HT2Creceptor signaling may bidirectionally influence reward-related behavior through an interaction with the mesolimbic dopamine (DA) system. Here we directly test this hypothesis by examining how modulating 5-HT2Creceptor activity affects DA-dependent behaviors and relate these effects to changes in nucleus accumbens (NAc) DA release. In C57BL/6 mice, locomotor activity and responding for a conditioned reinforcer (CRf), a measure of incentive motivation, were examined following treatment with three 5-HT2Creceptor ligands: the agonist CP809101 (0.25–3 mg/kg), the antagonist SB242084 (0.25–1 mg/kg), or the antagonist/inverse agonist SB206553 (1–5 mg/kg). We further tested whether doses of these compounds that changed locomotor activity and responding for a CRf (1 mg/kg CP809101, 0.5 mg/kg SB242084, or 2.5 mg/kg SB206553) also altered NAc DA release using in vivo microdialysis in anesthetized mice. CP809101 reduced locomotor activity, responding for a CRf, and NAc DA release. In contrast, both SB242084 and SB206553 enhanced locomotor activity, responding for a CRf, and NAc DA release, although higher doses of SB206553 produced opposite behavioral effects. Pretreatment with the non-selective DA receptor antagonist α-flupenthixol prevented SB242084 from enhancing responding for a CRf. Thus blocking tonic 5-HT2Creceptor signaling can release serotonergic inhibition of mesolimbic DA activity and enhance reward-related behavior. The observed bidirectional effects of 5-HT2Creceptor ligands may have important implications when considering the 5-HT2Creceptor as a therapeutic target for psychiatric disorders, particularly those presenting with motivational dysfunctions.

To enable the experimental assessment of the seismic performance of full-scale nonstructural elements with multiple engineering parameters (EDPs), a three-layer testbed named Nonstructural Element Simulator on Shake Table (NEST) has been developed. The testbed consists of three consecutive floors of steel structure. The bottom two floors provide a space to accommodate a full-scale room. To fully explore the flexibility of NEST, we propose a novel control strategy to generate the required shake table input time histories for the testbed to track the target floor motions of the buildings of interest with high accuracy. The control strategy contains two parts: an inverse dynamic compensation via simulation of feedback control systems (IDCS) algorithm and an offline iteration procedure based on a refined nonlinear numerical model of the testbed. The key aspects of the control strategy were introduced in this paper. Experimental tests were conducted to simulate the seismic responses of a full-scale office room on the 21stfloor of a 42-story high-rise building. The test results show that the proposed control strategy can reproduce the target floor motions of the building of interest with less than 20% errors within the specified frequency range.

Poor impulse control is associated with an increased propensity to develop an addiction and may contribute to relapse as high impulsive subjects appear to attribute greater salience toward drug-paired stimuli. In these studies, we determined whether trait impulsivity also predicts the desire to obtain natural reward-paired stimuli. Rats trained on the 5-choice serial reaction time task to measure impulsive action (Experiment 1) or a delay-discounting task to measure impulsive choice (Experiment 2) were separated into low, intermediate, or high impulsive action (L-IA, I-IA, H-IA) or choice (L-IC, I-IC, H-IC) groups. The motivation to obtain a conditioned stimulus (CS) paired with water-reward was subsequently determined by measuring responding for the CS as a conditioned reinforcer (CRf). Dopamine release in the nucleus accumbens was also measured using in vivo microdialysis. The effects of amphetamine were assessed on all tests. In Experiment 1, amphetamine increased impulsive action in all groups. L-IA rats initially demonstrated the highest responding for the CRf. Amphetamine increased responding for the CRf and this effect was augmented in L-IA rats. Dopamine release following amphetamine was greatest in L-IA subjects. In Experiment 2, amphetamine increased impulsive choice for L-IC and I-IC rats. However, all groups responded similarly for the CRf and dopamine release was moderately greater in L-IC rats. In conclusion, impulsive choice was unrelated to responding for a CRf. L-IA subjects initially attributed enhanced salience to a CS and exhibited greater dopamine release. Lower dopamine release in H-IA rats could result in reduced reinforcing properties of the CRf.

Scenario approach is a widely used tool in portfolio risk management, however, it often runs into dilemma when determining the distribution of asset returns with insufficient information, which will be used to simulate the scenarios. Also the quality of generated scenarios are not guaranteed even when the distribution of asset returns is known exactly. A set-valued scenario approach was proposed by Zhu, et al. (2015) as a possible remedy. As a necessary supplement of the results proposed by Zhu, et al. (2015), this paper theoretically investigates the convergent property of the numerical solution based on the set-valued scenario approach under the condition that the underlying distribution is known.

In this paper, we consider a cognitive radio network scenario, where two primary users want to exchange information with each other and meanwhile, one secondary node wishes to send messages to a cognitive base station. To meet the target quality of service (QoS) of the primary users and raise the communication opportunity of the secondary nodes, a cognitive bidirectional relaying (BDR) scheme is examined. First, system outage probabilities of conventional direct transmission and BDR schemes are presented. Next, a new system parameter called operating region is defined and calculated, which indicates in which position a secondary node can be a cognitive relay to assist the primary users. Then, a cognitive BDR scheme is proposed, giving a transmission protocol along with a time-slot splitting algorithm between the primary and secondary transmissions. Information-theoretic metric of ergodic capacity is studied for the cognitive BDR scheme to evaluate its performance. Simulation results show that with the proposed scheme, the target QoS of the primary users can be guaranteed, while increasing the communication opportunity for the secondary nodes.

Immobilization of ammonium and phosphate by zeolites synthesized from low-calcium (LC-Z) and high-calcium (HC-Z) fly ashes is studied. LC-Z has higher ammonium immobilization capacity while HC-Z has better performance in phosphate uptake. As part of Ca 2+ released from HC-Z compete with ammonium the exchangeable sites in LC-Z, LC-Z can affect phosphate immobilization of HC-Z, and HC-Z also lowers ammonium uptake of LC-Z. Separate dosing of LC-Z and HC-Z, i.e., first LC-Z and then HC-Z, is proved better than mixed dosing at simultaneous immobilization of ammonium and phosphate. The effect parameters for phosphate and ammonium immobilization of LTH-Z are investigated. [ABSTRACT FROM AUTHOR]

The authors describe a novel drug strategy designed as a primary screen to discover either antagonist or agonist compounds targeting G-protein-coupled receptors (GPCRs). The incorporation of a nuclear localization sequence (NLS, a 5 amino acid substitution), in a location in helix 8 of the GPCR structure, resulted in ligand-independent receptor translocation from the cell surface to the nucleus. Blockade of the GPCR-NLS translocation from the cell surface was achieved by either antagonist or agonist treatments, each achieving their result in a sensitive concentration-dependent manner. GPCR-NLS translocation and blockade occurred regardless of the identity of the G-protein-coupling, and thus this assay is also ideally suited for identification of compounds targeting orphan GPCRs. The GPCR-NLS trafficking was visualized by fusion to fluorescent detectable proteins. Quantification of this effect was measured by determining the density of cell surface receptors, using enzyme fragment complementation in a manner suitable for high-throughput screening. Thus, the authors have developed a cellular assay for GPCRs suitable for compound screening without requiring prior identification of an agonist or knowledge of G-protein-coupling.

We provided evidence for the formation of a novel phospholipase C-mediated calcium signal arising from coactivation of D1 and D2 dopamine receptors. In the present study, robust fluorescence resonance energy transfer showed that these receptors exist in close proximity indicative of D1-D2 receptor heterooligomerization. The close proximity of these receptors within the heterooligomer allowed for cross-phosphorylation of the D2 receptor by selective activation of the D1 receptor. D1-D2 receptor heterooligomers were internalized when the receptors were coactivated by dopamine or either receptor was singly activated by the D1-selective agonist (±)-6-chloro-7,8-dihydroxy-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrobromide (SKF 81297) or the D2-selective agonist quinpirole. The D2 receptor expressed alone did not internalize after activation by quinpirole except when coexpressed with the D1 receptor. D1-D2 receptor heterooligomerization resulted in an altered level of steady-state cell surface expression compared with D1 and D2 homooligomers, with increased D2 and decreased D1 receptor cell surface density. Together, these results demonstrated that D1 and D2 receptors formed heterooligomeric units with unique cell surface localization, internalization, and transactivation properties that are distinct from that of D1 and D2 receptor homooligomers.

Modified natural zeolites (MNZ) are widely used in pollutant removal, but how to address these MNZ that have adsorbed pollutants must be considered. Selenium is an essential trace element for metabolism and is also a water pollutant. Selenium is adsorbed in the water by MNZ in this study first. Then the Brassica chinensis L. was planted in the soil which contains the MNZ loaded with selenium (MNZ-Se) to explore selenium uptake. MNZ-Se release tests in water and soil were also considered. The results showed the following: (1) The maximum adsorption capacity of MNZ for selenium is 46.90 mg/g. (2) Water release experiments of MNZ-Se showed that regardless of how the pH of the aqueous solution changes, the trend of the release of selenium from MNZ-Se in aqueous solution is not affected and first decreases before stabilizing. (3) Soil release experiments of MNZ-Se showed that the selenium content in the soil increased and reached the concentration in the standard of selenium-rich soil. Addition amount and soil pH value will affect the release ratio. The release ratio of MNZ-Se in the water was higher than that in the soil. (4) With an increase in the soil MNZ-Se content, the selenium content in the soil and B. cincreases. Above all, MZN can be a good medium for water pollutant removal and soil improvement.

Polymerase chain reaction (PCR) was used to amplify portions of homeobox genes present in a human 11-week fetal brain cDNA library. One of these PCR products was determined by sequencing to be theGastrulation and brain specific-2gene (GBX2). Screening this human fetal brain cDNA library with probes specific forGBX2led to the identification of a 2151-bp cDNA clone. The nucleotide sequence of the cDNA clone encodes for a protein of 347 amino acid residues. The amino acid sequence of theGBX2homeodomain is identical (100%) to the that of homologous gene,Gbx2,expressed in the developing mouse embryo and virtually identical (97%) to a gene expressed in the developing chicken embryo,CHox7.The 5′ end of theGBX2gene contains a CpG island in the untranslated region and a trinucleotide (CCG)8repeat in the coding region. The amino-terminal end of the GBX2 protein is proline-rich, with 30 proline residues in one stretch of 120 amino acids. A single 2.2-kb transcript was detected by Northern analysis in the developing human CNS as well as in other tissues. The human genomic clone forGBX2was also isolated, characterized, and mapped to 2q36(d)–q37 by somatic cell hybrid analysis and fluorescencein situhybridization. These studies provide a framework for designing future experiments that are needed to determine the functional significance of this gene in CNS development.