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The frequent occurrence of voltage instability in a modern power system is alarming and thus, has been of great concern to power system utilities. In this paper, a new performance index based on the power flow solutions for voltage stability assessment of a power system is presented. First, the voltage deviation with respect to reactive power load variation at each load bus is found. Thereafter, the performance voltage bus index for each load bus is computed. An improved modal analysis technique (IMAT) is used to identify weak nodes that are liable to voltage instability in a power system. This technique uses a submatrix of the full Jacobian matrix for voltage stability analysis. Comparison of the proposed method is done with existing voltage stability indices and the conventional modal analysis technique (CMAT). The effectiveness of all the approaches presented are tested on both Western system coordinating Council (WSCC) 9-bus, IEEE 30 bus and IEEE 57 bus test systems. Results obtained show that the proposed techniques can serve as an alternative tool to other conventional techniques for voltage stability assessment in a power system and can be of tremendous benefits in the planning and operation of a power system by system operators. [ABSTRACT FROM AUTHOR]

Background: Among the 13 families of early-diverging eudicots, only Circaeasteraceae (Ranunculales), which consists of the two monotypic genera Circaeaster and Kingdonia, lacks a published complete plastome sequence. In addition, the phylogenetic position of Circaeasteraceae as sister to Lardizabalaceae has only been weakly or moderately supported in previous studies using smaller data sets. Moreover, previous plastome studies have documented a number of novel structural rearrangements among early-divergent eudicots. Hence it is important to sequence plastomes from Circaeasteraceae to better understand plastome evolution in early-diverging eudicots and to further investigate the phylogenetic position of Circaeasteraceae. Results: Using an Illumina HiSeq 2000, complete plastomes were sequenced from both living members of Circaeasteraceae: Circaeaster agrestis and Kingdonia uniflora. Plastome structure and gene content were compared between these two plastomes, and with those of other early-diverging eudicot plastomes. Phylogenetic analysis of a 79-gene, 99-taxon data set including exemplars of all families of early-diverging eudicots was conducted to resolve the phylogenetic position of Circaeasteraceae. Both plastomes possess the typical quadripartite structure of land plant plastomes. However, a large ~49 kb inversion and a small ~3.5 kb inversion were found in the large single-copy regions of both plastomes, while Circaeaster possesses a number of other rearrangements, particularly in the Inverted Repeat. In addition, infA was found to be a pseudogene and accD was found to be absent within Circaeaster, whereas all ndh genes, except for ndhE and ndhJ, were found to be either pseudogenized (ΨndhA, ΨndhB, ΨndhD, ΨndhH and ΨndhK)orabsent (ndhC, ndhF, ndhI and ndhG)in Kingdonia. Circaeasteraceae was strongly supported as sister to Lardizabalaceae in phylogenetic analyses. Conclusion: The first plastome sequencing of Circaeasteraceae resulted in the discovery of several unusual rearrangements and the loss of ndh genes, and confirms the sister relationship between Circaeasteraceae and Lardizabalaceae. This research provides new insight to characterize plastome structural evolution in early-diverging eudicots and to better understand relationships within Ranunculales. [ABSTRACT FROM AUTHOR]

Background: Simulation-based training (SBT) has become a standard for medical education. However, the efficacy of simulation based training in airway management education remains unclear. Methods: The aim of this study was to evaluate all published evidence comparing the effectiveness of SBT for airway management versus non-simulation based training (NSBT) on learner and patient outcomes. Systematic review with meta-analyses were used. Data were derived from PubMed, EMBASE, CINAHL, Scopus, the Cochrane Controlled Trials Register and Cochrane Database of Systematic Reviews from inception to May 2016. Published comparative trials that evaluated the effect of SBT on airway management training in compared with NSBT were considered. The effect sizes with 95% confidence intervals (CI) were calculated for outcomes measures. Results: Seventeen eligible studies were included. SBT was associated with improved behavior performance [standardized mean difference (SMD):0.30, 95% CI: 0.06 to 0.54] in comparison with NSBT. However, the benefits of SBT were not seen in time-skill (SMD:-0.13, 95% CI: -0.82 to 0.52), written examination score (SMD: 0.39, 95% CI: -0.09 to 0.86) and success rate of procedure completion on patients [relative risk (RR): 1.26, 95% CI: 0.96 to 1.66]. Conclusion: SBT may be not superior to NSBT on airway management training. [ABSTRACT FROM AUTHOR]

Man-made objects, such as buildings and roads, which are important targets for information extraction from high spatial resolution (HSR) remote sensing images, often feature straight boundaries. This study employs this knowledge on HSR image segmentation by embedding a straight-line constraint in region-based image segmentation. A new concept called collinear and ipsilateral neighborhood is proposed and applied to hard-boundary constraint-based image segmentation for accuracy improvement. In the experimental areas, the method accuracy measured by recall ratio r increases from 0.036 to 0.048 (on the average] after the refinement, with significantly smaller decreases in precision p that are all less than 0.006. In sum, the proposed technique effectively reduces over-segmentation errors and maintains the same level of under-segmentation error ratio, particularly in man-made areas. It facilitates subsequent object-based image analyses, including feature extraction, object recognition, and classification. [ABSTRACT FROM AUTHOR]

Anew neural network based optimization algorithm is proposed. The presented model is a discrete-time, continuous-state Hopfield neural network and the states of the model are updated synchronously. The proposed algorithm combines the advantages of traditional PSO, chaos and Hopfield neural networks: particles learn fromtheir own experience and the experiences of surrounding particles, their search behavior is ergodic, and convergence of the swarmis guaranteed. The effectiveness of the proposed approach is demonstrated using simulations and typical optimization problems. [ABSTRACT FROM AUTHOR]

A simple smooth chaotic system, which showed a 3-layer sphere chaotic attractor, is investigated. It is found that this chaotic attractor is a limit cycle instead of chaotic attractor. This situation was caused by the simulation time which is too short to reach its real status. It also shows that it is not reliable to construct chaotic system based only on the Šhilnikov criterion without finding the exact homoclinic orbits. Then a chaotic system with the real sphere shape is proposed. This proposed system is investigated through numerical simulations and analyses including time phase portraits, Lyapunov exponents, bifurcation diagrams and Poincaré section. [ABSTRACT FROM AUTHOR]

In this paper, a fractional 3-dimensional (3-D) 4-wing quadratic autonomous system (Qi system) is analyzed. Time domain approximation method (Grunwald-Letnikov method) and frequency domain approximation method are used together to analyze the behavior of this fractional order chaotic system. It is found that the decreasing of the system order has great effect on the dynamics of this nonlinear system. The fractional Qi system can exhibit chaos when the total order less than 3, although the regular one always shows periodic orbits in the same range of parameters. In some fractional order, the 4 wings are decayed to a scroll using the frequency domain approximation method which is different from the result using time domain approximation method. A surprising finding is that the phase diagrams display a character of local self-similar in the 4-wing attractors of this fractional Qi system using the frequency approximation method even though the number and the characteristics of equilibria are not changed. The frequency spectrums show that there is some shrinking tendency of the bandwidth with the falling of the system states order. However, the change of fractional order has little effect on the bandwidth of frequency spectrum using the time domain approximation method. According to the bifurcation analysis, the fractional order Qi system attractors start from sink, then period bifurcation to some simple periodic orbits, and chaotic attractors, finally escape from chaotic attractor to periodic orbits with the increasing of fractional order α in the interval [0.8,1]. The simulation results revealed that the time domain approximation method is more accurate and reliable than the frequency domain approximation method. [ABSTRACT FROM AUTHOR]

In this paper, several smooth canonical 3-D continuous autonomous systems are proposed in terms of the coefficients of nonlinear terms. These systems are derived from the existing 3-D four-wing smooth continuous autonomous chaotic systems. These new systems are the simplest chaotic attractor systems which can exhibit four wings. They have the basic structure of the existing 3-D four-wing systems, which means they can be extended to the existing 3-D four-wing chaotic systems by adding some linear and/or quadratic terms. Two of these systems are analyzed. Although the two systems are similar to each other in structure, they are different in dynamics. One is sensitive to the initializations and sampling time, but another is not, which is shown by comparing Lyapunov exponents, bifurcation diagrams, and Poincaré maps. [ABSTRACT FROM AUTHOR]

This paper analyzes the pitchfork and Hopf bifurcations of a new 3-D four-wing quadratic autonomous system proposed by Qi et al. The center manifold technique is used to reduce the dimensions of this system. The pitchfork and Hopf bifurcations of the system are theoretically analyzed. The influence of system parameters on other bifurcations are also investigated. The theoretical analysis and simulations demonstrate the rich dynamics of the system. [ABSTRACT FROM AUTHOR]

A Retraction Note to this paper has been published: https://doi.org/10.1007/s11051-021-05226-0 [ABSTRACT FROM AUTHOR]

为充分利用油莎豆油及改善人造奶油的营养品质，以油莎豆油和棕榈硬脂为原料制备人造奶油，与5种市售人造奶油的理化性质进行对比分析，并将其应用到面包制作中。结果表明:自制人造奶油的熔点（33.51 ℃）在5种市售人造奶油的熔点范围内（32.33~45.43 ℃），且满足LS/T 3217—1987标准要求；自制人造奶油具有较好的延展性、抗渗油能力以及良好的口融性，同时拥有较低的饱和脂肪酸含量（ ＜40%）、动脉粥样硬化指数（0.56）和血栓形成指数（1.15）；与市售人造奶油相比，自制人造奶油具有较多的β′晶型以及较好的热性质；添加自制人造奶油的面包，具有较低的烘焙损失率、较大的比容和较好的感官评分。综上，自制人造奶油具有良好的发展潜力，有望代替市售人造奶油应用到面包、饼干、甜点等焙烤领域。In order to fully utilize tiger nut oil and improve the nutritional quality of margarine, margarine was prepared from tiger nut oil and palm stearin, and its physicochemical properties were compared with five commercial margarines, and it was applied to bread making. The results showed that the melting point of homemade margarine (33.51 ℃) was within the melting point range of five commercial margarines(32.33-45.43 ℃) and met the requirements of LS/T 3217-1987. Homemade margarine had good ductility, resistance to oil seepage, and good oral thawing properties, while it had a low saturated fatty acid content(

Under the background of emerging agricultural education, practice bases are an important place to train profession talented person that match social needs, so it is very important to build stable and long-term practice bases. At present, the main problems in the construction of practice bases for postgraduates in local colleges and universities are mainly focusing on construction and neglecting management, imperfect cooperation mechanism and lack of teaching management effectively. It is of great significance to build a long-term management mechanism to ensure the education quality of practice bases. Therefore, constructing the mode of " double integration and double promotion of production and education" with practice bases as the carrier and realizing the organic combination of industrial needs and postgraduate projects is an important idea for local colleges and universities to train professional degree postgraduates to " know agriculture, love agriculture, strengthen agriculture and promote agriculture", and it also provides a reference for the mechanism construction of postgraduate bases. [ABSTRACT FROM AUTHOR]

Quinoa has been recognized as the sole "comprehensive nutritional crop"; however, it is susceptible to pre-harvest sprouting (PHS). While quantitative reverse transcription polymerase chain reaction (RT-qPCR) has been extensively employed for gene expression level detection, the selection of suitable reference genes is imperative to ensure precise gene expression quantification across diverse conditions. This study aims to identify stable reference genes in quinoa seeds under ABA and GA, in order to provide a basis for subsequent research on PHS. Seeds were subjected to different concentrations of ABA and GA (10 µM, 50 µM, 100 µM, and 200 µM). The most suitable treatment concentration was determined based on seed viability. Here, MON1, GAPDH, EIF3, EF1a, ACT, TUB1, and TUB6 were selected as candidate genes. The suitability of these reference genes under different conditions was assessed using various methods including Ct values, geNorm, NormFinder, BestKeeper, Delta Ct, and RefFinder. Based on the results obtained from the hormone experiments, it was observed that the application of 100 µM ABA and 200 µM GA yielded the most advantageous outcomes. Additionally, the most appropriate reference genes for different treatments are ACT and TUB1 (H2O treatment), EIF3 and MON1 (ABA, GA treatment and also for the combined data set of the three groups). However, GAPDH exhibited the least stability across all treatments. In summary, ACT is recommended as the reference gene for natural quinoa germination, while EIF3 and MON1 should be used for ABA and GA treatments. [ABSTRACT FROM AUTHOR]

Background: Common buckwheat (Fagopyrum esculentum) is an important staple food crop in southwest China, where drought stress is one of the largest limiting factors that lead to decreased crop production. To reveal the molecular mechanism of common buckwheat in response to drought stress, we performed a comprehensive transcriptomics study to evaluate gene expression profiles of common buckwheat during PEG-mediated drought treatment. Results: In total, 45 million clean reads were assembled into 53,404 unigenes with an average length of 749 bp and N50 length of 1296 bp. A total of 1329 differentially expressed genes (DEGs) were identified by comparing wellwatered and drought-treated plants, out of which 666 were upregulated and 663 were downregulated. Furthermore, we defined the functional characteristics of DEGs using GO and KEGG classifications. GO enrichment analysis showed that the DEGs were significantly overrepresented in four categories, namely, "oxidoreductase activity," "oxidation-reduction process," "xyloglucan:xyloglucosyl transferase activity," and "apoplast." Using KEGG pathway analysis, a large number of annotated genes were overrepresented in terms such as "plant hormone signal transduction," "phenylpropanoid biosynthesis," "photosynthesis," and "carbon metabolism." Conclusions: These results can be further exploited to investigate the molecular mechanism of common buckwheat in response to drought treatment and could supply with valuable molecular sources for abiotic-tolerant elite breeding programs in the future. [ABSTRACT FROM AUTHOR]