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This paper proposes a decentralized dynamic event-triggered control method of aero-engine T-S fuzzy system, aiming to achieve both exponential stabilization of aero-engine networked control systems (NCSs) and reduction in network communication loads. Firstly, a novel decentralized dynamic event-triggered mechanism (DETM) is developed to regulate data transmissions in each communication channel independently. The closed-loop model is then established, by considering network-induced delays, dynamic quantization effects, external disturbance, and parameter perturbation. Stability criteria are derived using the Lyapunov–Krasovskii method, and a collaborative design method based on linear matrix inequalities (LMIs) is proposed for controller, quantizers, and DETM. Lastly, a parameter tuning method based on the iL-SHADE algorithm is proposed for better feasibility of the obtained LMIs. Simulation results show that the proposed method has good robustness to multi-uncertainty conditions and can effectively reduce communication resource wastage while ensuring well control performance across a wide range of flight envelopes. [ABSTRACT FROM AUTHOR]

Key message: Expression of Cre recombinase by AtRps5apro or AtDD45pro enabled Cre/lox-mediated recombination at an early embryonic developmental stage upon crossing, activating transgenes in the hybrid cowpea and tobacco. Genetic engineering ideally results in precise spatiotemporal control of transgene expression. To activate transgenes exclusively in a hybrid upon fertilization, we evaluated a Cre/lox-mediated gene activation system with the Cre recombinase expressed by either AtRps5a or AtDD45 promoters that showed activity in egg cells and young embryos. In crosses between Cre recombinase lines and transgenic lines harboring a lox-excision reporter cassette with ZsGreen driven by the AtUbq3 promoter after Cre/lox-mediated recombination, we observed complete excision of the lox-flanked intervening DNA sequence between the AtUbq3pro and the ZsGreen coding sequence in F1 progeny upon genotyping but no ZsGreen expression in F1 seeds or seedlings. The incapability to observe ZsGreen fluorescence was attributed to the activity of the AtUbq3pro. Strong ZsGreen expression in F1 seeds was observed after recombination when ZsGreen was driven by the AtUbq10 promoter. Using the AtDD45pro to express Cre resulted in more variation in recombination frequencies between transgenic lines and crosses. Regardless of the promoter used to regulate Cre, mosaic F1 progeny were rare, suggesting gene activation at an early embryo-developmental stage. Observation of ZsGreen-expressing tobacco embryos at the globular stage from crosses with the AtRps5aproCre lines pollinated by the AtUbq3prolox line supported the early activation mode. [ABSTRACT FROM AUTHOR]

Sensor technology application is the key for intelligent welding process. Multiple sensors fusion has shown their significant advantages over single sensor which can only provide limited information. In this paper, a feature-level data fusion methodology was presented to automatically evaluate seam quality in real time for Al alloy in gas tungsten arc welding by means of online arc sound, voltage and spectrum signals. Based on the developed algorithms in time and frequency domain, multiple feature parameters were successively extracted and selected from sound and voltage signals, while spectrum distribution of argon atoms related to seam penetration were carefully analyzed before feature parameters selection. After the synchronization of heterogeneous feature parameters, the feature-level-based data fusion was conducted by establishing a classifier using support vector machine and 10-fold cross validation. The test results indicate that multisensory-based classifier has higher accuracy i.e., 96.5873 %, than single sensor-based one in term of recognizing seam defects, like under penetration and burn through from normal penetration. [ABSTRACT FROM AUTHOR]

Agrobacterium-mediated plant transformation is typically conducted by inoculating plant tissues with an Agrobacterium suspension containing approximately 10-10 bacteria mL, followed by a 2-3-d co-culture period. Use of longer co-culture periods could potentially increase transformation efficiencies by allowing more time for Agrobacterium to interact with plant cells, but bacterial overgrowth is likely to occur, leading to severe tissue browning and reduced transformation and regeneration. Low bacterial inoculum levels were therefore evaluated as a means to reduce the negative outcomes associated with long co-culture. The use of low inoculum bacterial suspensions (approximately 6 × 10 bacteria mL) followed by long co-culture (15 d) led to the production of an average of three transformed sunflower shoots per explant while the use of high inoculum (approximately 6 × 10 bacteria mL) followed by short co-culture (3 d) led to no transformed shoots. Low inoculum and long co-culture acted synergistically, and both were required for the improvement of sunflower transformation. Gene expression analysis via qRT-PCR showed that genes related to plant defense response were generally expressed at lower levels in the explants treated with low inoculum than those treated with high inoculum during 15 d of co-culture, suggesting that low inoculum reduced the induction of plant defense responses. The use of low inoculum with long co-culture (LI/LC) led to large increases in sunflower transformation efficiency. This method has great potential for improving transformation efficiencies and expanding the types of target tissues amenable for transformation of different plant species. [ABSTRACT FROM AUTHOR]

Regeneration of sunflower plants from tissue culture can be problematic due to inefficiencies in shoot elongation and subsequent rooting. To minimize exposure to cytokinins, which can negatively impact shoot elongation and rooting, a cytokinin pulse treatment was evaluated by placing cotyledonary tissues from sunflower seeds onto a shoot induction medium containing 1.5 mg L 6-benzylaminopurine and 0.2 mg L 1-naphthaleneacetic acid for 0, 2, 4, 8, 12, and 16 d, prior to transfer to an elongation medium containing 0.1 mg L gibberellic acid. The 16-d pulse treatment gave the highest numbers of shoot primordia, but shoot development was minimal and only 0.4 well-developed shoots could be obtained per explant. The 4-d pulse treatment followed by 14 d of culture on elongation medium led to the production of 5.5 well-developed shoots per explant. For plant recovery, well-developed shoots obtained with the 4-d pulse treatment followed by a 14-d elongation treatment were micrografted onto in vitro seedlings, with graft survival of over 60%. Short pulse treatments (4- and 8-d), followed by culture on elongation medium, generated well-developed shoots that seemed to be more responsive to micrografting than shoots obtained with the 16-d pulse treatment. The use of the 4-d pulse treatment with micrografting of well-developed shoots significantly improved the efficiency of whole-plant recovery of sunflower. [ABSTRACT FROM AUTHOR]

Leaf tissue is widely used for regeneration of many different plants, but an efficient regeneration method using leaf tissue of sunflower is not yet available. In this report, adventitious shoots were obtained from primary leaves of 7-day-old sunflower seedlings. If seeds were germinated on a medium without cytokinin, only 25 % of the leaf explants produced shoots after 3 weeks of culture on a shoot induction medium (SIM) containing 1.5 mg L benzylaminopurine (BA), giving an average of three shoot primordia per leaf. Shoot induction was enhanced up to sixfold when seeds were germinated on media containing BA or 6-(γ, γ-dimethylallylamino)purine at 5 mg L and higher, or kinetin at 15 mg L and above, with an average of 12-19 shoot primordia per leaf. Shoots further developed and elongated following transfer to a medium containing 0.1 mg L gibberellic acid. The highest number of developed shoots was obtained from leaves preconditioned with 5 mg L BA, with 1.9 developed shoots per explant. Histological analysis of leaves from seedlings germinated on a medium containing 5 mg L BA revealed increased cell division primarily in the leaf surface tissue on the adaxial side of the mid vein. After the leaves were excised and plated on SIM, these cells continued to divide and differentiate to form adventitious shoots, suggesting that the cytokinin-containing germination medium preconditioned leaves for shoot organogenesis. An in vitro micrografting approach was developed using the elongated shoots as scions, and 57 % of grafted shoots survived to form plants. [ABSTRACT FROM AUTHOR]

In this paper, a novel methodology for real-time nondestructive defect detection, particularly hydrogen-assisted porosity of an aluminum alloy welded using pulsed gas tungsten arc welding is presented based on the plasma spectroscopy signal of the welding arc. The emission lines of the hydrogen atom at 656.3 nm and argon atom at 641.63 nm were analyzed to extract multiple feature parameters, from which more sensitive features were then selected for monitoring by means of Fisher distance criteria. The threshold detection method based on the features selected from the spectrum was found to be feasible in detecting the welding defect, i.e., porosity in real-time. Furthermore, the established predicting model based on SVM-CV also successfully identified defect of porosity from normal welding with high accuracy. [ABSTRACT FROM AUTHOR]

Soybean ( Glycine max) promoters from an actin gene ( GmActin), a ribosomal protein S11 gene ( GmRpS11) and a heat shock protein 90 gene ( GmHsp90), identified as being active during early induction of soybean somatic embryogenesis, were cloned, fused to the green fluorescence protein ( gfp) gene and reintroduced into soybean for evaluation. All promoters displayed development- and tissue-specific regulation based on the expression of GFP in transgenic soybean. In seedlings, these three promoters gave rise to strong GFP expression in young roots, with very high levels of expression in the vascular tissues and root primordia. In older plants, promoter activity was observed in the vascular cambium of petioles, leaf midribs, and in the mesophyll of expanding leaves, but at reduced levels. The GmActin promoter gave very high GFP expression in developing and mature seeds. All three promoters displayed high activity following induction of somatic embryogenesis from immature soybean cotyledons. Comparison of promoter-regulated GFP transgene expression with transcriptome analysis using RNA-Seq revealed agreement in expression intensity in roots, leaves, and flowers but exceptions for expression in young developing seeds. Evaluation of specific promoters in transgenic plants is needed for proper elucidation of promoter-regulated transgene activity. [ABSTRACT FROM AUTHOR]

Arc sensing plays a significant role in the control and monitoring of welding quality for aluminum alloy pulsed gas touch argon welding (GTAW). A method for online quality monitoring was proposed based on the analysis of acquired arc voltage signal, through which two algorithms of feature extraction were developed in time and frequency domain, respectively. In time domain,the wavelet packet transform was carried out to eliminate the pulse interference of the feature parameter curve. In frequency domain, the other new algorithm was proposed based on the voltage power spectrum density (PSD) which was calculated by using the improved Welch algorithm and divided into five frequency bands before the statistic parameters were extracted. The correlation between the feature parameters in different frequency bands and welding defects were carefully analyzed to select a more sensitive one as the monitoring parameters. The proposed algorithms on this paper were verified to be capable of detecting lack of penetration, burn through, and the defect caused by lack of gas. [ABSTRACT FROM AUTHOR]

We study the number of zeros of Abelian integrals for the quadratic centers having almost all their orbits formed by cubics, when we perturb such systems inside the class of all polynomial systems of degree n [ABSTRACT FROM AUTHOR]

It is proved in this paper that the lowest upper bound of the number of the isolated zeros of the Abelian integral is two for h∈(−1/12, 0), where Γh is the compact component of H(x, y)=(1/2) y2+(1/3) x3+(1/4) x4=h, and α, β, γ are arbitrary constants. [ABSTRACT FROM AUTHOR]

By means of finitely-smooth normal form theory and the method of infinitesimal analysis, it is proved that the cyclicity of a planar codimension 3 polycycle S(2) is three and the complete bifurcation diagram is provided. [ABSTRACT FROM AUTHOR]