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This paper presents a 802.11ac low-noise amplifier with bypass function integrated in 0.36 μm SiGe BiCMOS process. In order to meet the specifications of the criteria, the methods for optimizing noise, power gain and stability were given. In the circuit design, the SiGe HBTs were designed with inductive emitter degeneration structure. According to the simulation results, the HBT low-noise amplifier is unconditionally stable when the power supply voltage is 5 V and the noise figure(NF) is about 2.2 dB with small signal gain 13.3 dB, and 7.2 dB with insertion loss about 7.2 dB for LNA enabled and LNA bypass status, respectively. The input third order intercept point is about 10.2 dBm with two-tone signal at 2.412 and 2.437 GHz, respectively. Total input power is 0 dBm(-3 dBm/tone).

The increasing penetration rate of distributed resources in the distribution network has brought about significant volatility and uncertainty problems. Demand response (DR) can flexibly change the energy consumption method of the user to balance supply and demand. This paper first considers the spatial distribution characteristics of DR resources to schedule DR resources to construct a distributed resource cloud-edge collaborative scheduling framework. Based on this, the distribution network scheduling requirements are combined with the multi-time scale characteristics of DR. A three-stage cloud-edge collaborative optimization scheduling strategy for distributed resources in the distribution network is proposed, which allocates the multi-time scale scheduling tasks of DR resources to the cloud and edge. Secondly, taking the cloud and edge as the optimization platform, a three-stage optimization decision-making model of the distribution network is established. In the day-ahead stage, the global optimization decision is made by combining cloud-centralized optimization with edge-independent optimization. In the intraday stage, edge-rolling optimization is carried out. In the real-time stage, the edge-distributed calculation is based on the consensus algorithm. Finally, the effectiveness and economy of the proposed model and strategy are verified by an example analysis. [ABSTRACT FROM AUTHOR]

Aims Airborne transmission of diseases presents a serious threat to human health, so effective air disinfection technology to eliminate microorganisms in indoor air is very important. This study evaluated the effectiveness of a non-thermal plasma (NTP) air disinfector in both laboratory experiments and real environments. Methods and results An experimental chamber was artificially polluted with a bioaerosol containing bacteria or viruses. Additionally, classroom environments with and without people present were used in field tests. Airborne microbial and particle concentrations were quantified. A 3.0 log10 reduction in the initial load was achieved when a virus-containing aerosol was disinfected for 60 min and a bacteria-containing aerosol was disinfected for 90 min. In the field test, when no people were present in the room, NTP disinfection decreased the airborne microbial and particle concentrations (P  < 0.05). When people were present in the room, their constant activity continuously contaminated the indoor air, but all airborne indicators decreased (P  < 0.05) except for planktonic bacteria (P =  0.094). Conclusions NTP effectively inactivated microorganisms and particles in indoor air. [ABSTRACT FROM AUTHOR]

SUMMARY: Anthocyanin and catechin production in tea (Camellia sinensis) leaves can positively affect tea quality; however, their regulatory mechanisms are not fully understood. Here we report that, while the CsMYB75‐ or CsMYB86‐directed MYB–bHLH–WD40 (MBW) complexes differentially activate anthocyanin or catechin biosynthesis in tea leaves, respectively, CsMYBL2a and CsMYBL2b homologs negatively modified the light‐ and temperature‐induced anthocyanin and catechin production in both Arabidopsis and tea plants. The MBW complexes activated both anthocyanin synthesis genes and the downstream repressor genes CsMYBL2a and CsMYBL2b. Overexpression of CsMYBL2b, but not CsMYBL2a, repressed Arabidopsis leaf anthocyanin accumulation and seed coat proanthocyanin production. CsMYBL2b strongly and CsMYBL2a weakly repressed the activating effects of CsMYB75/CsMYB86 on CsDFR and CsANS, due to their different EAR and TLLLFR domains and interactions with CsTT8/CsGL3, interfering with the functions of activating MBW complexes. CsMYBL2b and CsMYBL2a in tea leaves play different roles in fine‐tuning CsMYB75/CsMYB86–MBW activation of biosynthesis of anthocyanins and catechins, respectively. The CsbZIP1–CsmiR858a–CsMYBL2 module mediated the UV‐B‐ or cold‐activated CsMYB75/CsMYB86 regulation of anthocyanin/catechin biosynthesis by repressing CsMYBL2a and CsMYBL2b. Similarly, the CsCOP1–CsbZIP1–CsPIF3 module, and BR signaling as well, mediated the high temperature repression of anthocyanin and catechin biosynthesis through differentially upregulating CsMYBL2b and CsMYBL2a, respectively. The present study provides new insights into the complex regulatory networks in environmental stress‐modified flavonoid production in tea plant leaves. Significance Statement: It is not clear how tea (Camellia sinensis) leaves control the biosynthesis and accumulation of catechins, anthocyanins, and other types of flavonoids under various environmental conditions. In the present study we show that two MYB repressors (CsMYBL2b and CsMYBL2a) differently fine‐tune the high temperature‐ or light stress‐regulated anthocyanin and catechin production through interfering with CsMYB75‐ or CsMYB86‐directed MYB–bHLH–WD40 (MBW) complexes. CsbZIP1–CsmiR858a, CsCOP1–CsbZIP1–CsPIF3, and BR signaling are involved in this stress‐modified CsMYBL2b and CsMYBL2a expression, which further regulate MBW activation of catechin and anthocyanin production. [ABSTRACT FROM AUTHOR]

Electrochemical oxygen reduction reaction (ORR) for preparing hydrogen peroxide (H2O2) is a promising way to replace the anthraquinone method. The key to H2O2 production is the development of catalysts to regulate the oxygen reduction reaction pathway. Here, nitrogen-doped Nb2CTx was prepared by NH3 annealing method. Compared with precursor Nb2AlC (67.01%) and pure Nb2CTx (75.70%), nitrogen-doped Nb2CTx exhibited excellent performance for 2e− ORR with > 90% H2O2 selectivity (at 0.4 V vs. reversible hydrogen electrode (RHE)). Faradic efficiency of nitrogen-doped Nb2CTx reached 80.75%, whereas those for Nb2AlC and Nb2CTx were 60.35% and 39.27%, respectively. A desirable catalytic stability for 50 h was observed. Density functional theory (DFT) calculations indicated excellent activity of the nitrogen-doped Nb2CTx was attributed to the introduction of N. This excellent activity was conducive to the adsorption of oxygen and promoted the formation of the OOH intermediate. This work can serve as an important reference for regulating the electronic structure of MXene to expand the application area in the electrochemical field. [ABSTRACT FROM AUTHOR]

Stomata perform important functions in plant photosynthesis, respiration, gas exchange, and interactions with environments. However, tea plant stomata development and functions are not known. Here, we show morphological changes during stomata development and genetic dissection of stomata lineage genes regulating stomata formation in tea developing leaves. Different tea plant cultivars displayed clear variations in the stomata development rate, density and size, which are closely related to their tolerance against dehydration capabilities. Whole sets of stomata lineage genes were identified to display predicted functions in regulating stomatal development and formation. The stomata development and lineage genes were tightly regulated by light intensities and high or low temperature stresses, which affected stomata density and function. Furthermore, lower stomatal density and larger size were observed in triploid tea varieties as compared to those in diploid plant. Key stomata lineage genes such as CsSPCH s, CsSCRM, and CsFAMA showed much lower expression levels, whereas negative regulators CsEPF1 and CsYODA s had higher expression levels in triploid than in diploid tea varieties. Our study provides new insight into tea plant stomatal morphological development and the genetic regulatory mechanisms on stomata development under abiotic stresses and genetic backgrounds. The study lays a foundation for future exploring of the genetic improvement of water use efficiency in tea plants for living up to the challenge of global climate change. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotube (MWCNT)-modified MoS2/BiVO4 was manufactured and used for the photoelectrochemical (PEC) detection of hydrogen peroxide (H2O2) and hypochlorite (ClO−). A solvothermal method was used to synthesize an MWCNT/MoS2/BiVO4 composite that showed perfect PEC properties because the MWCNTs and MoS2/BiVO4 heterostructures increased the composite's stability against photocorrosion. Compared with the same signal of MWCNT/MoS2/BiVO4, the photocurrent signal of other composites was much smaller upon irradiation by visible light. According to this PEC sensor, the linear range of the H2O2 concentration was 1–200 μ M and 280–1560 μ M at pH = 7. 4 based on the same pH when detecting ClO− concentrations between 0.5–10 μ M and 20–340 μ M in a bleach sample. As a result, this sensor can be used to detect reactive oxygen species (ROS) in practical samples. MWCNT/MoS2/BiVO4 composite was synthesized by two-step ways and showed wide linear range, low detection limit and great application potential in the photoelectrochemical (PEC) detection of hydrogen peroxide (H2O2) and hypochlorite (ClO–). [ABSTRACT FROM AUTHOR]