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The journal retracts the article titled “A Kalman Filter-Based Distributed Cyber-Attack Mitigation Strategy for Distributed Generator Units in Meshed DC Microgrids” [...]

Arabidopsis AGAMOUS (AG) plays a crucial role in specifying stamen and carpel identities, floral meristem identity determination, and repression of the A-function. Ilex verticillata (Aquifoliaceae) is a dioecious shrub, whereby an individual plant has either male or female flowers with vestigial organs of the opposite sex. The molecular mechanism of male and female organ development in I. verticillata remains unknown. In order to identify the possible roles of AG-like genes in regulating floral development in I. verticillata, AG ortholog (IlveAG) and its promoter (pIlveAG) from the male and female flowers of I. verticillata were separately isolated. IlveAG is highly expressed in stamens, pistils, and sepals of male and female flowers. Moreover, obvious GUS staining was observed in the inflorescence and sepals, stamens, and pistils of mature flowers in pIlveAG::GUS Arabidopsis. The 35S::IlveAG Arabidopsis showed obviously early flowering. Moreover, IlveAG could substitute for endogenous AG to rescue the stamen and pistil in the Arabidopsis ag-1 mutant. In addition, expression of IlveAG can inhibit the development of sepals and petals (two outer whorls of floral organs) in wild-type and ag-1 Arabidopsis. Our findings suggest that IlveAG has a conservative C-function and plays key roles in determination of reproductive floral organs (stamen and carpel) identity and meristem determinacy. Our results provide more details to understand the role of AG orthologs in the development of male and female flowers in woody plants.

To ensure fast dynamics and the stability of multiple distributed generator units (DGUs) in DC microgrids, communication links among the controllers of DGUs are generally adopted. However, those communication channels are vulnerable to cyber-attacks. To alleviate this hassle, a Kalman Filter (KF)-based distributed cyber-attack mitigation strategy, which is highly involved in both primary and secondary control, is proposed in this paper. The KF, as a robust state estimator, is utilized to accurately estimate the authentic terminal voltages and currents of the DGUs. Based on the discrepancies between the estimated and measured parameters of the systems under cyber-attacks, the proposed control can adaptively compensate the attack signals via an adaptive proportional integral (API) controller and a fractional API (FAPI) controller in cyber-attack-mitigation layers. The main advantage of using the proposed control scheme compared to conventional schemes is the fast dynamic response. The simulation results verify this merit by comparing the adopted KF and comparing it with conventional artificial neural networks (ANN), while the experimental results validate that effectiveness of the proposed control and showcase the superiority of the FAPI control in terms of its perfect compensation for different types of cyber-attacks.

To alleviate the hassle of false data injection (FDI) attacks on distributed generators (DGs) in microgrids, a communication encryption-based distributed cooperative control is proposed in this paper. Compared to the conventional distributed control strategies, the proposed control scheme is simpler with much less complex evaluation mechanism by upgrading the secondary control to a second-order control based on the finite-time control theory while combining an encryption strategy. The proposed algorithm provides constant injections to eliminate the impact of FDI attacks based on a robust communication system. The effectiveness and high efficiency of the proposed control scheme is validated in an IEEE 34 Node Test Feeder system with six DGs as a microgrid cyber-physical system (CPS) under different FDI attacks.

Palmer Amaranth (Amaranthus palmeri, Amaranthaceae) is one of the most competitive, troublesome, and noxious weeds causing significant yield reductions in various crops. A. palmeri was also a herbicide-resistant weed causing a serious eco-environmental problem. Given that the process of invasion is dynamic, the A. plamer invasion may already be quite severe where invasive species management and surveys are chronically lacking. Predicting the potential habitat of A. palmeri can help to develop effective measures for early warning and long-term detection. However, the invasive history and distribution patterns of A. palmeri in China remain largely unknown. Here, the invasive history and distribution patterns of A. palmeri from 1985 to 2022 in China were reconstructed, and then the potential geographical distribution of A. palmeri was predicted under current and future climate scenarios (SSP1-2.6, SSP2-4.5, SSP5-8.5) using the optimal MaxEnt model (V 3.4.4) and ArcGIS 10.8.2. The mean AUC values of A. palmeri were 0.967. Under the current climate conditions, the suitable habitat areas for A. palmeri reached 1,067,000 km2 in China and were mainly distributed in north and central China. Under the future scenarios, the highly suitable habitats were mainly distributed in Beijing, Tianjin, and Hebei. Under SSP2–4.5, the future suitable areas will reach the maximum and expand to 1,411,100 km2 in the 2060s. The centroid distribution would northwestward extend under future climate scenarios. The human footprint index, mean temperature of the warmest quarter (Bio_10), April wind speed (Wind_4), temperature seasonality (standard deviation × 100) (bio_4), topsoil gravel content (T_gravel), and precipitation of warmest quarter (Bio_18) were key environmental variables affecting distribution and growth of A. palmeri. Climate change would increase the risk of A. palmeri expanding to high latitudes. Our results will help in developing effective strategies for the early warning, prevention, control, and management of A. palmeri in China.

Arabidopsis AGAMOUS (AG) play roles in determining stamens’ and carpels’ identities, floral meristem determinacy, and repression of the A-function. Gynostemium fused by stamens and carpels is a characteristic reproductive structure in orchid flowers, which shows a considerable difference from the reproductive organs of eudicots and other monocot species. The molecular basis of orchid gynostemium development remains largely unknown. Here, we report the identification and functional characterization of two AG-like genes, CyfaAG1 and CyfaAG2, and their promoters from C. faberi. Both CyfaAG1 and CyfaAG2 are highly expressed in the anther cap, gynostemium, and ovary. Ectopic expression of CyfaAG1 and CyfaAG2 promotes early flowering of wild-type Arabidopsis. Moreover, ectopic expression of CyfaAG1 completely rescues floral defects in the Arabidopsis ag-1 mutant, while ectopic expression of CyfaAG2 only completes filament and carpel development. Our findings suggest that CyfaAG1 acts as an evolutionarily conserved C-function gene in determining reproductive organ identity and mediating floral meristem determinacy. CyfaAG2 redundantly mediates the C-function in floral meristem determinacy and gynostemium development. Our results provided more details to understand how the C-class function has been partitioned in orchids, and the roles of two AG orthologs in regulating gynostemium development in C. faberi.

Path coverage attracts many interests in some scenarios, such as object tracing in sensor networks. However, the problem of how to conserve the constrained energy of sensors is rarely considered in existing research. This paper studies two problems in the energy conservation of sensor networks that have not been addressed before. The first problem is called the least movement of nodes on path coverage. It first proves the problem as NP-hard, and then uses curve disjunction to separate each path into some discrete points, and ultimately moves nodes to new positions under some heuristic regulations. The utilized curve disjunction technique makes the proposed mechanism unrestricted by the linear path. The second problem is called the largest lifetime on path coverage. It first separates all nodes into independent partitions by utilizing the method of largest weighted bipartite matching, and then schedules these partitions to cover all paths in the network by turns. We eventually analyze the energy cost of the two proposed mechanisms, and evaluate the effects of some parameters on performance through extensive experiments, respectively.

Optimizing the sowing date of rice can change the seasonal patterns and distributions of climate factors during the crop growing season, making it one of the most effective ways to adapt to climate change and achieve high yield. A four–year field experiment (2018–2021) was conducted at Jingzhou Agricultural Meteorological Experiment Station, central China, with four different sowing dates (SD) each year, late April (SD1), early May (SD2), mid–May (SD3) and late May (SD4). Dry matter accumulation, grain yield and climate conditions were observed across sowing dates. Our findings revealed that delaying the sowing date from early May to mid or late May could increase grain yield by 5.6% to 8.6%. However, sowing too early could increase heat stress, decrease the net effective accumulated temperature, inhibit rice growth, and reduce grain yield. On the other hand, sowing too late could increase the risk of low temperatures after flowering. From the perspective of increasing net effective accumulated temperature, reducing heat stress and low temperature after flowering, mid to late May was the most favorable sowing date to ensure high yield. It is suggested that optimizing rice sowing dates can effectively avoid the threat of heat stress and better match thermal resources, thereby increasing rice productivity.

Recently, stimuli-responsive supramolecular gels have received significant attention because their properties can be modulated through external stimuli such as heat, light, electricity, magnetic fields, mechanical stress, pH, ions, chemicals and enzymes. Among these gels, stimuli-responsive supramolecular metallogels have shown promising applications in material science because of their fascinating redox, optical, electronic and magnetic properties. In this review, research progress on stimuli-responsive supramolecular metallogels in recent years is systematically summarized. According to external stimulus sources, stimuli-responsive supramolecular metallogels, including chemical, physical and multiple stimuli-responsive metallogels, are discussed separately. Moreover, challenges, suggestions and opportunities regarding the development of novel stimuli-responsive metallogels are presented. We believe the knowledge and inspiration gained from this review will deepen the current understanding of stimuli-responsive smart metallogels and encourage more scientists to provide valuable contributions to this topic in the coming decades.

Arabidopsis PISTILLATA (PI) encodes B-class MADS-box transcription factor (TF), and works together with APETALA3 (AP3) to specify petal and stamen identity. However, a small-scale gene duplication event of PI ortholog was observed in common buckwheat and resulted in FaesPI_1 and FaesPI_2. FaesPI_1 and FaesPI_2 were expressed only in the stamen of dimorphic flower (thrum and pin) of Fagopyrum esculentum. Moreover, intense beta-glucuronidase (GUS) staining was found in the entire stamen (filament and anther) in pFaesPI_1::GUS transgenic Arabidopsis, while GUS was expressed only in the filament of pFaesPI_2::GUS transgenic Arabidopsis. In addition, phenotype complementation analysis suggested that pFaesPI_1::FaesPI_1/pFaesPI_2::FaesPI_2 transgenic pi-1 Arabidopsis showed similar a flower structure with stamen-like organs or filament-like organs in the third whorl. This suggested that FaesPI_2 only specified filament development, but FaesPI_1 specified stamen development. Meanwhile, FaesPI_1 and FaesPI_2 were shown to function redundantly in regulating filament development, and both genes work together to require a proper stamen identity. The data also provide a clue to understanding the roles of PI-like genes involved in floral organ development during the early evolution of core eudicots and also suggested that FaesPI_1 and FaesPI_2 hold the potential application in bioengineering to develop a common buckwheat male sterile line.

Common buckwheat (Fagopyrum esculentum) produces distylous flowers with undifferentiated petaloid tepals, which makes it obviously different from flowers of model species. In model species Arabidopsis, APETALA3 (AP3) is expressed in petal and stamen and specifies petal and stamen identities during flower development. Combining with our previous studies, we found that small-scale gene duplication (GD) event and alternative splicing (AS) of common buckwheat AP3 orthologs resulted in FaesAP3_1, FaesAP3_2 and FaesAP3_2a. FaesAP3_2 and FaesAP3_2a were mainly expressed in the stamen of thrum and pin flower. Promoters functional analysis suggested that intense GUS staining was observed in the whole stamen in pFaesAP3_2::GUS transgenic Arabidopsis, while intense GUS staining was observed only in the filament of stamen in pFaesAP3_1::GUS transgenic Arabidopsis. These suggested that FaesAP3_1 and FaesAP3_2 had overlapping functions in specifying stamen filament identity and work together to determine normal stamen development. Additionally, FaesAP3_2 and FaesAP3_2a owned the similar ability to rescue stamen development of Arabidopsis ap3-3 mutant, although AS resulted in a frameshift mutation and consequent omission of the complete PI-derived motif and euAP3 motif of FaesAP3_2a. These suggested that the MIK region of AP3-like proteins was crucial for determining stamen identity, while the function of AP3-like proteins in specifying petal identity was gradually obtained after AP3 Orthologs acquiring a novel C-terminal euAP3 motif during the evolution of core eudicots. Our results also provide a clue to understanding the early evolution of the functional specificity of euAP3-type proteins involving in floral organ development in core eudicots, and also suggested that FaesAP3_2 holds the potential application for biotechnical engineering to develop a sterile male line of F. esculentum.

Common buckwheat is a traditional alternative crop that originated from the northwest of China and is widely cultivated worldwide. However, common buckwheat is highly sensitive to drought stress, especially at the seedling stage, and the molecular mechanisms underlying the response to drought stress still remain elusive. In this study, we analyzed the stress phenotypes of buckwheat seedlings under drought condition. The results showed the wrinkled cotyledon due to the decrease of relative water content (RWC) in response to the increased activity of antioxidant enzymes. Transcriptomic analysis was further performed to analyze the regulation patterns of stress-responding genes in common buckwheat cotyledons and roots under drought stress conditions. Characterizations of the differentially expressed genes (DEGs) revealed differential regulation of genes involved in the photosynthesis and oxidoreductase activity in cotyledon, and that they were highly related to the post-transcriptional modification and metabolic process in root. There were 180 drought-inducible transcription factors identified in both cotyledons and roots of the common buckwheat. Our analysis not only identified the drought responsive DEGs and indicated their possible roles in stress adaption, but also primarily studied the molecular mechanisms regulating the drought stress response in common buckwheat.