Copper (Cu) is a trace mineral nutrient essential for plant growth; consequently, its uptake, trafficking, and redistribution are precisely controlled. Currently, little is known about the underlying ...regulatory mechanisms in rice. In this work, we identified OsHIPP24 as a Cu metallochaperone in rice. Heterologous expression of
OsHIPP24
in wild-type yeast (
Saccharomyces cerevisiae
) strain BY4741 increased accumulation of Cu, as well as cadmium (Cd).
OsHIPP24
was expressed constitutively in most tissues of rice, including root, stem, leaf, leaf sheath, internode, rachis, and spikelet, and particularly high in root stele along with the vascular bundle of the shoot. Overexpression or knockout of
OsHIPP24
in rice led to stunted growth and reduced plant height, regardless of Cu levels in the growth medium. Taken together, these observations indicated that the physiological roles of OsHIPP24 involve the delivery of metal micronutrients via vascular tissues, and that OsHIPP24 plays a crucial role in the growth of rice.
The reverse gate leakage mechanism of W-gate and TiN-gate AlGaN/GaN high-electron-mobility transistors (HEMTs) with N
2
plasma surface treatment is investigated using current–voltage (
I
–
V
) and ...capacitance–voltage (
C
–
V
) characteristics and theoretical calculation analysis. It is found that the main reverse gate leakage mechanism of both devices is the trap-assisted tunneling (TAT) mechanism in the entire reverse bias region (–30 V to 0 V). It is also found that the reverse gate leakage current of the W-gate AlGaN/GaN HEMTs is smaller than that of the TiN gate at high reverse gate bias voltage. Moreover, the activation energies of the extracted W-gate and TiN-gate AlGaN/GaN HEMTs are 0.0551 eV–0.127 eV and 0.112 eV–0.201 eV, respectively.
Surface acoustic wave (SAW) devices based on piezoelectric thin-films such as ZnO and AlN are widely used in sensing, microfluidics and lab-on-a-chip applications. However, for many of these ...applications, the SAW devices will inevitably be used in acid or alkali harsh environments, which may cause their early failures. In this work, we investigated the behavior and degradation mechanisms of thin film based SAW devices in acid and alkali harsh environments. Results show that under the acid and alkali attacks, chemical reaction and corrosion of ZnO devices are very fast (usually within 45 s). During the corrosion, the crystalline orientation of the ZnO film is not changed, but its grain defects are significantly increased and the grain sizes are decreased. The velocity of ZnO-based SAW devices is decreased due to the formation of porous structures induced by the chemical reactions. Whereas an AlN thin-film based SAW device does not perform well in acid-alkali conditions, it might be able to maintain a normal performance without obvious degradation for more than ten hours in acid or alkali solutions. This work could provide guidance for the applications of both ZnO or AlN-based SAW devices in acid/alkali harsh environments.
Surface acoustic wave (SAW) devices based on piezoelectric thin-films such as ZnO and AlN are widely used in sensing, microfluidics and lab-on-a-chip applications.
With the occurrence of information leakage events of online ride-hailing, the information security of Internet of Vehicles has been highly valued by the society. Once the information of the Internet ...of Vehicles is exposed by the online ride-hailing platform or stolen by hackers, it will pose a fatal threat to the personal and property safety of users, and even cause a major information security accident to the whole society. Based on a post-quantum cryptography system, this paper proposes a practical privacy protection scheme for ride-hailing route information, which can present the complete statistical aggregation operation of the route and the frequency from the starting point to the destination without the visibility of the ride-hailing platform, and ensure the data privacy security of a single vehicle. Compared with representative multi-vehicle aggregation solutions, we not only guarantee message privacy, confidentiality, integrity, forward and backward security, anti-man in attack and anti-redial attack, but also achieve multi-dimensional aggregation, CCA security and anti-quantum attack. Through the analysis of the experiment, the cost of our scheme is reasonable. Therefore, the scheme is more practical in this scenario.
This paper proposes the extended state observer (ESO)-based active disturbance rejection control (ADRC) for the speed tracking of an autonomous vehicle. Uncertainties, both in the vehicle plant and ...in the sensors, such as nonlinear uncertainties due to the powertrain dynamics, variations in rolling resistance and air resistance, are all estimated in real-time by an extended state observer (ESO). Furthermore, a simple vehicle longitudinal dynamics model, including a mean value engine model (MVEM), is implemented to obtain the parameters in ADRC and design a feedforward controller to enhance the controller’s performance. The proposed controller is validated through CarSim®/Simulink® simulations and road tests. The simulation validates the adaptiveness of the proposed controller against the well-tuned proportional integral derivative (PID) controller, and the speed tracking error of the proposed controller is within 1.26% in simulation. Simulation results also show that fuel consumption can be improved by 3.6% by changing the accelerator pedal depth and positive rate. Finally, the road tests are completed under four kinds of road conditions, and the maximum tracking error is smaller than 0.5 km/h.
This paper considers current personalized recommendation approaches based on computational social systems and then discusses their advantages and application environments. The most widely used ...recommendation algorithm, personalized advice based on collaborative filtering, is selected as the primary research focus. Some improvements in its application performance are analyzed. First, for the calculation of user similarity, the introduction of computational social system attributes can help to determine users’ neighbors more accurately. Second, computational social system strategies can be adopted to penalize popular items. Third, the network community, identity, and trust can be combined as there is a close relationship. Therefore, this paper proposes a new method that uses a computational social system, including a trust model based on community relationships, to improve the user similarity calculation accuracy to enhance personalized recommendation. Finally, the improved algorithm in this paper is tested on the online reading website dataset. The experimental results show that the enhanced collaborative filtering algorithm performs better than the traditional algorithm.
Health rumors arbitrarily spread in mainstream social media on the internet. Health rumors emerged in China during the outbreak of COVID-19 in early 2020. Many midelders/elders (age over 40 years) ...who lived in Wuhan believed these rumors.
This study focused on designing a serious game as an experimental program to prevent and control health rumors. The focus of the study was explicitly on the context of the social networking service for midelders/elders.
This research involved 2 major parts: adopting the Transmission Control Protocol model for games and then, based on the model, designing a game named "Fight With Virus" as an experimental platform and developing a cognitive questionnaire with a 5-point Likert scale. The relevant variables for this experimental study were defined, and 10 hypotheses were proposed and tested with an empirical study. In total, 200 participants were selected for the experiments. By collecting relevant data in the experiments, we conducted statistical observations and comparative analysis to test whether the experimental hypotheses could be proved.
We noted that compared to traditional media, serious games are more capable of inspiring interest in research participants toward their understanding of the knowledge and learning of health commonsense. In judging and recognizing the COVID-19 health rumor, the test group that used game education had a stronger ability regarding identification of the rumor and a higher accuracy rate of identification. Results showed that the more educated midelders/elders are, the more effective they are at using serious games.
Compared to traditional media, serious games can effectively improve midelders'/elders' cognitive abilities while they face a health rumor. The gameplay effect is related to the individual's age and educational background, while income and gender have no impact.
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