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In the refining and chemical industry, distillation is one of the prime processes and is a multivariable control problem, which involves interaction amongst several control loops and exhibit dead time in the dynamic behavior. The analysis and controller design of processes inheriting dead time is a challenging task, and the presence of plant uncertainties and disturbances makes it challenging to exert quality control over time. In this paper, a template and bounds free approach is explored for the simultaneous synthesis of quantitative feedback theory (QFT) based robust controller and pre-filter for Wood and Berry distillation column with multiple time delays. This presented method simplifies the QFT controller synthesis for MIMO systems and eliminates the need of ' Schauder fixed point theory ' to express the m × m MIMO system into analogous m 2 MISO plants before the QFT controller synthesis. Using the presented approach, an optimal MIMO QFT controller and pre-filter are synthesized in a single step, which else conventionally follows a long sequential design process. In the presented approach, the QFT controller design problem has been posed as an optimization problem and is solved using genetic algorithm. The work has been compared with the work already reported in literature. The designed multivariate QFT controller efficiently mitigate the effect of parametric uncertainties, satisfy the design requirements in a very tight envelope, minimize the interaction amongst the control loops and offers improved the disturbance rejection. • Work explores a template and bounds free approach for the simultaneous synthesis of QFT controllers. • Presented method eliminates the need of ' Schauder fixed point theory ' for conventional MIMO QFT controller synthesis. • Designed MIMO QFT controller efficiently mitigate the parametric uncertainties and time delays. • Comparison of the proposed technique with the reported methods is also presented. [ABSTRACT FROM AUTHOR]

This paper presents a novel integral terminal sliding mode control (ITSMC) algorithm compounded with Barrier Lyapunov's Function (BLF) for high precision output tracking objective of uncertain N-dimensional strict feedback class of non-linear systems subjected to non-infringement of system output constraint. Besides, the proposed algorithm also employs uncertainty and disturbance estimator (UDE) technique for abating the existence of unknown mismatched and matched uncertainties. Most of the preliminary SMC schemes encompass the UDE technique to cope with unknown matched uncertainties only. However, the presented method embodies the dynamic surface control (DSC) architecture to get rid of the matching architectural constraint in UDE approach as well as 'complexity explosion' concern in backstepping approach. Additionally, the introduced method also applies the notion of symmetric BLF to enforce strict bounds on output tracking deviation from its reference value. To emphasize on the strengths of devised methodology, two examples are simulated by comparing the derived outcomes with already existing techniques in literature. [ABSTRACT FROM AUTHOR]

Four contrasting varieties of guar, RGC-1002 and RGC-1038, drought tolerant, while, Sarada and RGC-936, drought sensitive, were monitored in watered and drought. The water status, phenolics, plant anatomy and transcript level of genes related to anatomical traits were assessed. The study aimed to decipher the anatomical adaptations of guar plants in response to water stress. The physiological determinants, relative water content (RWC), water potential (ψ), and leaf membrane damage, declined under drought in all four varieties although, the decrement was lesser in the tolerant varieties. Furthermore, the tolerant cultivars subjected to water stress recorded higher accumulation of total phenolic content, anthocyanin and lignin, which efficiently scavenge the reactive oxygen species. The results suggest that the cultivars RGC-1002 and RGC-1038 are better able to resist drought-induced oxidative stress than Sarada and RGC-936. Moreover, leaf, petiole, stem and root anatomical traits viz. size of epidermal cell, parenchyma, width of cortex layer, and diameter of xylem vessels were narrowed in all the varieties although, the decrement was lesser in the tolerant varieties under drought. The expression analysis of genes revealed that drought-tolerant varieties showed enhanced mechanical support for water conduction by up-regulation of genes, Phenylalanine ammonia-lyase1 (PAL1), cinnamate-4-hydroxylase (C4H), 4-coumarate-CoA ligase (4CL), cinnamoyl-CoA reductase (CCR), caffeoyl-CoA O-methyltransferase (CCOMT), and cinnamyl-alcohol dehydrogenase (CAD6) in water stress conditions. The alterations in physio-anatomical, biochemical and gene expression traits in tolerant guar varieties enabled them to maintain steady nutrient transport while reducing the risk of embolisms and increasing water-flow resistance for better survival in water stressed conditions. [Display omitted] • Drought increases membrane damage and caused electrolyte leakage. • Cell size of epidermis, cortex and xylem reduced in leaf, petiole, stem, root. • Drought increases accumulation of lignin, total phenolic content and anthocyanins. • Transcript level of lignin pathway genes upregulated during drought. [ABSTRACT FROM AUTHOR]

This paper proposes a novel fractional order sliding mode control approach to address the issues of stabilization as well as tracking of an N-dimensional extended chained form of fractional order non-holonomic system. Firstly, the hierarchical fractional order terminal sliding manifolds are selected to procure the desired objectives in finite time. Then, a sliding mode control law is formulated which provides robustness against various system uncertainties or external disturbances. In addition, a novel fractional order uncertainty estimator is deduced mathematically to estimate and mitigate the effects of uncertainties, which also excludes the requirement of their upper bounds. Due to the omission of discontinuous control action, the proposed algorithm ensures a chatter-free control input. Moreover, the finite time stability of the closed loop system has been proved analytically through well known Mittag-Leffler and Fractional Lyapunov theorems. Finally, the proposed methodology is validated with MATLAB simulations on two examples including an application of fractional order non-holonomic wheeled mobile robot and its performances are also compared with the existing control approach. [ABSTRACT FROM AUTHOR]

A novel EM (electromagnetic) design of low observable antenna using active hybrid-element frequency selective surface (FSS) as ground plane is presented in this paper for stealth applications. The EM characteristics of active hybrid-element FSS structure are reconfigured from reflecting mode to transmitting mode and vice versa by switching ON and OFF the PIN diode at 10 GHz. In ON state of diode (reflection mode), the FSS structure shows extremely less transmission (<−40 dB), which corroborates its suitability for ground plane of antenna. In OFF state of diode (transmission mode), it exhibits bandpass response over the frequency range 9.3–10.7 GHz corresponding to very less power loss (<−0.42 dB). Further, a low observable microstrip patch antenna (MPA) is designed using proposed FSS structure as ground plane and its EM characteristics are studied using commercial software package. In ON state of diode, the FSS-based MPA is observed to perform as typical MPA and its out-of-band radar cross section (RCS) also reduces as well. In OFF state of diode, FSS-based antenna does not radiate while passes EM signal impinging on its structure in result reduces significantly in-band RCS (up to 15.8 dBmm 2 ) as compared to conventional MPA. Finally, a prototype active FSS-based antenna is fabricated and measured for proof-of-the concept. [ABSTRACT FROM AUTHOR]

The accumulation of arsenic in crop plants has become a worldwide concern that affects millions of people. The major source of arsenic in crop plants is irrigation water and soil. In this study, Serendipita indica , an endophytic fungus, was used to investigate the protection against arsenic and its accumulation in the tomato plant. We found that inoculation of S. indica recovers seed germination, plant growth and improves overall plant health under arsenic stress. A hyper-colonization of fungus in the plant root was observed under arsenic stress, which results in reduced oxidative stress via modulation of antioxidative enzymes, glutathione, and proline levels. Furthermore, fungal colonization restricts arsenic mobilization from root to shoot and fruit by accumulating it exclusively in the root. We observed that fungal colonization enhances the arsenic bioaccumulation factor 1.48 times in root and reduces the arsenic translocation factor by 2.96 times from root to shoot and 13.6 times from root to fruit compared to non colonized plants. Further, investigation suggests that S. indica can tolerate arsenic by immobilizing it on the cell wall and accumulating it in the vacuole. This study shows that S. indica may be helpful for the reduction of arsenic accumulation in crops grown in arsenic-contaminated agriculture fields. • Arsenic induces hyper-colonization of fungus Serendipta indica in plant root. •Fungal colonization alleviates arsenic stress in colonized plant. •Fungus modulates antioxidative system in plants under arsenic stress. • S. indica induces arsenic accumulation in root with reduced mobilization to fruit. • S. indica adsorbs arsenic on the cell wall and stores it in the vacuole of the cell. [ABSTRACT FROM AUTHOR]

Unravelling the plants responses towards rising atmospheric [CO 2 ] have largely been explored in genetical and morpho-physiological contexts. However, epigenetic factors including DNA methylation which play critical roles in adaptation are largely unexplored. Here we investigated the methylome, transcriptome and morpho-physiological responses of the two Arabidopsis thaliana populations evolved at high (3400 m amsl) and low elevation (700 m amsl) zones to elevated [CO 2 ] (e[CO 2 ]). We show that depending on the origin of the population, there were local level variations in DNA methylation when exposed to e[CO 2 ], but global methyl cytosine (mC) content remained unchanged. Further, there was loss of methylation and more protein coding genes were differentially methylated than transposable elements and non-coding RNA genes, in both the populations but more so in the low elevation one. The differentially methylated genes of the two populations belonged to distinct functional categories. More genes related to methylation machinery were down-regulated in the high elevation population than the low elevation one. Although there was no correlation between methylation and gene expression at the global scale but a few genes exhibited methylation dependent expression level. Finally the hyper- and hypo-methylated status of a few genes due to e[CO 2 ] treatment were validated. Overall, our data suggested the two populations responded differently towards e[CO 2 ] with respect to methylome remodeling, phenotypic and molecular plasticity. However, methylome remodeling and molecular plasticity were more prominent in the low elevation population. Understanding the evolution of epigenetic response towards e[CO 2 ] may help in future crop improvement strategies. • Elevated CO 2 affects DNA methylation remodeling in Arabidopsis thaliana depending on origin of the population. • Methylome remodeling and molecular plasticity of the low elevation population were more than the higher elevation one. • More protein coding genes were differentially methylated in response to elevated CO 2. • Elevated CO 2 induced global gene expression and methylation is not co-linear. [ABSTRACT FROM AUTHOR]

Metallothioneins (MTs) are diverse class of cysteine-rich proteins having metal-chelation properties. The role of MTs has been demonstrated in different abiotic stresses and MTs have been designated as biomolecular stress markers. Chickpea is an important legume crop supplying proteins to humans, as well as acting as great soil-binders along with nitrogen-fixation capability. The present research deals with the development of transgenic chickpea overexpressing metallothionein type-1 (CarMT1) gene for analyzing its role in stress tolerance against drought and heavy metals. The overexpression construct was designed using binary expression vector, pBI121 and transformed in chickpea desi cultivar, Pusa-362 for functional validation by using sonication-assisted Agrobacterium -mediated transformation. The results indicated high transcript levels under the drought (22-folds) and changes in physiological (photosynthesis rate, transpiration rate, stomatal conductance, water-use efficiency) and biochemical (antioxidant enzymes and compatible solutes) parameters suggesting stress-mitigating roles of CarMT1. The transgenic seeds were evaluated for heavy metal stress adaptation that resulted in better seed survival efficiency under different heavy metal stresses. The results indicated beneficial roles of MT gene in transgenic lines of chickpea in presence of different abiotic stresses, which could pave the way for multi-stress tolerant crop development. A schematic representation of working of MT gene in response to drought stress in transgenic chickpea plants. [Display omitted] • CarMT1 gene over-expressed in chickpea indicates drought and heavy metal stress enduring roles. • Transgenic plants were better in seed germination and root growth. • Physio-biochemical and molecular characterization reported stress adaptive roles. • Transgenic plants resulted up to 22-fold change in expression in comparison to control. [ABSTRACT FROM AUTHOR]

• Peppermint based nanoemulsion has been synthesized by high energy sonication method. • 1% dose of PNE was able to inhibit the growth of A. solani. • 1% PNE reduce the disease severity caused by A. solani in tomato up to 87.5%. • PNE modulates plant physiology at biochemical, morphological, gene expression level. Early blight, caused by Alternaria solani is one of the most devastating disease affecting to the Solanum lycopersicum (tomato), reducing its productivity by 80%. The present study illustrates the synthesis of nanoemulsion using peppermint oil for potent antimicrobial activity against A. solani. A peppermint oil based nanoemulsion (PNE) was synthesized which was further characterized by Dynamic Light Scattering and Transmission Electron Microscopy. The nano-droplets present in nanoemulsion were spherical in shape with average size <100 nm. In-vitro antimicrobial activity of PNE was examined against A. solani with the carbendazim as positive control. A green-house study was performed to evaluate the antimicrobial efficacy and plant immunity developed by nanoemulsion as well as compared with carbendazim, chemical fungicide. PNE was much competent to reduce the disease severity up to 68.7% at 14th day and 87.5% at 21st day respectively. Physiological modulation was showed in tomato plants against A. solani, they were confirmed by measured the physical parameters, plant physiology, changes in leaf morphology and stress responses. A significant changes were found in proline and lipid peroxidation content in infected plants whereas nanoemulsion treated infected plants was able to cope-up from stress condition. Physical parameters and Scanning Electron Microscopy (SEM) analysis also revealed the similar observations. A reduced photosynthesis rate and transpiration rate were found in diseased plants as compared to other treatments, although stomatal conductance was not much affected. Defence responsive gene expression also up-regulated in PNE treated diseased plants than pathogen alone. Thus, the current study demonstrated the peppermint oil based nanoemulsion was more efficacious than chemical fungicide to early blight disease management in Solanum lycopersicum. [ABSTRACT FROM AUTHOR]