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Leakage and magnetizing inductances of transformer windings are routinely measured by power utilities during scheduled maintenance. They are often used to confirm the diagnosis of mechanical damages in windings after Swept Frequency Response Analysis shows a mismatch. Inductance measurements performed at power frequency can possibly reveal the presence of damages that have substantially progressed but cannot detect them at their nascent stages since inductances at power frequency remain almost unaltered. This paper investigates the possibility of using high-frequency inductance to this end considering a frequently encountered mechanical damage, viz., disk-space variation in a disk winding. Effect of disk-space variation is investigated in this article using FEM at first and inductances at different frequencies are considered: magnetizing and leakage inductances at 50 Hz, and inductance at a higher frequency region corresponding to winding resonances, say, 500 kHz. The inductance at high frequencies not only exhibited increased sensitivity compared to that at power frequency, but also captured the extent of damage. Simulations performed using Ansys Maxwell and experimental results on an actual 1- $\phi$ transformer are reported. Results show that the high-frequency inductance not only offers a considerably increased sensitivity to disk-space variation in windings compared to the power frequency inductances, but also provides insight regarding the extent of movement which is not apparent from the frequency response. [ABSTRACT FROM AUTHOR]

Turmeric rhizome (Curcuma longa L.) has been used without concern for safety as a culinary spice and traditional medicine under the ancient Ayurvedic medicinal system of India dating back nearly 4000 years. This preclinical safety evaluation was done to determine the safety of an oleoresin-based turmeric extract (CURCUGEN®). Guidelines from the Organization for Economic Co-operation and Development (OECD) directed the assessment of safety for the in vitro and in vivo application of CURCUGEN®. Safety of the herbal medicine was evaluated through the toxicological assessment of acute, oral, and 90-day repeated dosing, genotoxicity, and mutagenicity study. Genotoxicity tests included the in vitro bacterial reverse mutation test, chromosomal aberration test, and in vivo micronucleus test. The single dose of CURCUGEN® administered orally (gavage) to Sprague-Dawley (SD) rats resulted in a LD50 of >5000 mg/kg body weight. The subchronic assessment of CURCUGEN®, as administered to SD rats over 90 days resulted in a no observed adverse effect level (NOAEL) of 2000 mg/kg body weight/day. CURCUGEN® did not elicit any genotoxic or clastogenic effect in genotoxicity tests. The battery of safety studies carried out demonstrated that CURCUGEN® showed no evidence of general toxicity or genotoxicity. [ABSTRACT FROM AUTHOR]

Introduction: Urinary tract infections (UTI) are the most common infection encountered in the life of an individual irrespective of age and sex. Varying degree of antibiotic resistance shown by uropathogens against the routinely used antibiotics in the therapeutic regimen is a serious concern in treatment of UTI. This study was aimed at the isolation and demonstration of antibiogram pattern of organism responsible for acute UTI. Materials and methods: Clean catched mid stream urine (CCMSU) specimens collected from patients of different age group were cultured on blood agar and Mac Conkey's agar by standard loop culture method. These organisms were further identified by standard methods and antibiotic sensitivity was evaluated using Kirby Bauers disc diffusion method in accordance with CLSI guidelines. Results: A total of 1230 samples were collected from both males and females of age group 5 to 80. Among the total, 443 (36%) samples were positive for culture and showed significant bacteruria. Gram negative isolates were responsible for majority of infection and 86.9% isolates and Escherichia coli was the predominant among them (37.2%). Conclusion: Majority of the isolates showed resistance to drugs commonly used to treat UTI. Variations in sensitivity may be due to the inappropriate exposure of different localities as to antibiotics which can drive the development of resistance. From the results of this study, it is certain that choosing drugs for empiric treatment will be challenging as no single common drug can conveniently be recommended for UTI. [ABSTRACT FROM AUTHOR]

Objectives: Osteoarthritis (OA) is a common, chronic, progressive, skeletal, and degenerative disorder that commonly affects the knee joint which causes the disability of elderly people. This study aimed to assess the efficacy and safety of test supplement in subjects with OA of knee as compared to placebo. Methods: A total of 50 subjects aged between 40 to 75 years who were suffering from unilateral or bilateral OA of the knee for greater than 3 months (ACR criteria) were enrolled in the study and 47 subjects continued till end. The subjects were enrolled to either the test group or placebo group. The primary endpoint included the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index and secondary endpoint included Visual Analog Scale (VAS) scores and WOMAC sub score for the subjects. Results: After 60 days of treatment, there was a significant reduction in the mean WOMAC and VAS score in test group compared to placebo. It was also found to be safe and well tolerated. Conclusion: This study results provide a promising result for the test product as a useful alternative treatment option for the management of symptoms of OA. [ABSTRACT FROM AUTHOR]

Premature ejaculation (PE) is one of the foremost sex-related health problems among men. The global occurrence ranges from 20% to 30%, according to various studies. PE has a great impact on the men's quality of life, with deleterious effects such as embarrassment, frustration, and feeling of incompetence. Considering the necessity of treatment of PE, this study was planned to compare the efficacy and safety of OLNP-05 versus placebo for treating subjects suffering from PE. In this randomized clinical study, 60 men with PE were enrolled and randomly assigned to receive either OLNP-05 or placebo one capsule twice daily for a period of 8 weeks. Subjects were evaluated during visits on day 1, day 28, and day 56. Mean change from baseline in intravaginal ejaculatory latency time (IELT), improvement in premature ejaculation profile (PEP), and Clinical Global Impression-Improvement scale (CGI-I) were used to assess the efficacy of treatment. P-value <.05 was considered significant. At the end of the treatment, the improvement in IELT score in the OLNP-05 group was remarkably higher than the placebo. Subjects in the OLNP-05 treatment group also reported significantly greater improvement in PEP subscale score. Majority of OLNP-05-treated subjects were found to be in the "much improved" category as per CGI-I assessment. The result confirms the safety and efficacy of OLNP-05, therefore suggesting that OLNP-05 may be a safe and effective intervention for the management of PE. Trial registration: Clinical Trials Registry India (Registration No: CTRI/2017/08/009226, 02/08/2017). [ABSTRACT FROM AUTHOR]

Background. Curene® is a bioavailable formulation of turmeric  Curcucma longa extract comprising naturally derived curcuminoids formulated with proprietary Aquasome® technology. Curcuminoids were found to have anti-inflammatory properties by inhibiting Cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX) enzyme and hence have potential application in the treatment of Osteoarthritis (OA). To evaluate the safety and efficacy of Curene® a randomized, double blind, placebo controlled, parallel-group study was conducted in subjects with knee OA. Significant improvements in clinical endpoints were observed during the trial along with excellent safety profile. Methods. Fifty (50) subjects aged between 40 and 75 years who were suffering from unilateral or bilateral OA of the knee for greater than 3 months according to American College of Rheumatology (ACR) criteria were enrolled. They were randomized into two treatment groups; one group received Curene® 500 mg once daily and the other group received placebo. Efficacy was evaluated using change from baseline in Visual Analogue Scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score. Biochemical and hematological parameters including urine analysis were performed to evaluate the safety of Curene® in OA patients. Result. Forty-six (46) subjects completed the study. The reduction from baseline in total WOMAC score (also subscale scores) and VAS score resulted in statistically significant difference when compared to placebo. It was also found to be safe and well tolerated as there was no incidence of treatment related AEs. Conclusion. Curene® results in statistically significant and clinically meaningful reduction in pain, stiffness, and improvement in physical functioning in subjects suffering from knee OA. Curene® also demonstrates excellent safety profile during the study. Trial Registration. This trial is registered with Clinical Trial Registry, India, CTRI/2017/07/009044, registered on 14th July 2017, http://ctri.nic.in/Clinicaltrials/showallp.php?mid1=19264&EncHid=&userName=ocius%20life%20sciences. [ABSTRACT FROM AUTHOR]

This paper proposes a new method to determine the sizing and siting of diesel generators (DGs), photovoltaic (PV) solar panels, and batteries for off-grid systems. In this work, the objective is to reduce the total system cost while fulfilling the load demand and maintaining the power quality of the system, among other constraints. This is achieved by employing a two-stage particle swarm optimization algorithm; the first for siting and sizing of the system and the second for its scheduling. Three case studies, namely only DGs, DGs + PV, and DGs + PV + batteries systems, based on the energy requirement of an Indonesian island are presented. In addition, real solar irradiance and temperature data are utilized together with a measured load profile. The results reveal that a system that relies only on DGs is not able to keep the system voltage within the tolerable range (from 0.95 to 1.05 p.u.), while yielding a lifetime cost of 104 million USD. The DGs + PV system requires a lower lifetime cost, 67 million USD. Nevertheless, the voltage of the system reaches values lower than 0.95 p.u. for certain nodes during night-time as the PV are not able to provide power. Finally, the DGs + PV + batteries system yields the lowest cost, 64 million USD, and is able to keep the values of the voltage within the desired range, as batteries can provide power when PV are not operating. [ABSTRACT FROM PUBLISHER]

This paper presents an online methodology to detect and diagnose the inductor degradation in LCL filter integrated with Active Front End Rectifier (AFER) for electric drives in marine propulsion system (MPS). The proposed methodology monitors the leakage fluxes of converter-side inductor and compares it with the same under healthy condition to detect and diagnose the inductance degradation. The magnitude of leakage flux's fundamental component is extracted using the Fast Fourier Transform (FFT) and is used for detection of inductance degradation. Hence, inexpensive and low bandwidth magnetic flux sensors along with a simple FFT algorithm are used to detect and diagnose the inductance degradation. The leakage fluxes of the inductor during degradation are analyzed using the developed analytical model and validated on a laboratory prototype of 11.3-kW MPS test-rig. The validation was carried out for different degrees of converter-side inductor degradation from 3% to 19% under 33%, 73%, and 100% of full-load capacity of the MPS test-rig. Both estimated results using the analytical model and experimental results obtained are found to be in good agreement. The proposed online technique can detect and estimate the degraded inductance as low as 3% and is superior to the technique using grid currents in detecting the inductor abnormality. [ABSTRACT FROM AUTHOR]

Electric spring (ES), a new smart grid technology, has earlier been used for providing voltage and power stability in a weakly regulated/stand-alone renewable energy source powered grid. It has been proposed as a demand-side management technique to provide voltage and power regulation. In this paper, a new control scheme is presented for the implementation of the ES, in conjunction with noncritical building loads like electric heaters, refrigerators, and central air conditioning system. This control scheme would be able to provide power factor correction of the system, voltage support, and power balance for the critical loads, such as the building's security system, in addition to the existing characteristics of ES of voltage and power stability. The proposed control scheme is compared with original ES's control scheme where only reactive power is injected. The improvised control scheme opens new avenues for the utilization of the ES to a greater extent by providing voltage and power stability and enhancing the power quality in the renewable energy powered microgrids. [ABSTRACT FROM AUTHOR]

As power-electronics is playing a major role in modernization of the existing electrical grid towards renewable energy rich smart grid , isolated medium-voltage AC–low-voltage DC (MVAC-LVDC) power conversion has gained popularity for grid-connected applications. In this paper, an initial discussion is provided on existing solutions related to grid-connected MVAC-LVDC conversion, which briefly describes the shortcomings of the line-frequency-transformer (LFT) based conversion solutions and then discusses the various categories of isolated power-electronic conversion solutions based on modularity. A qualitative comparison of the isolated power-electronics based conversion solutions reveals the obvious merits of the cascaded modular conversion strategy over the modular multilevel, semi-modular and single-cell conversion strategies. Subsequently, comprehensive descriptions for each of the available single-phase isolated AC–DC conversion submodules in the literature are provided, along with pertinent illustrations of circuit diagrams and important electrical quantities' wave-shapes. Finally, a quantitative comparative evaluation of a 22 kV grid-connected 1 MVA power-rated MVAC-LVDC isolated converter's three-phase submodule possibilities along with comparable LFT based MVAC-LVDC solution is presented, while considering the criteria of efficiency (η), power density (ρ), cost (σ), failure rate (λ), number of components (N o C) and control complexity (C. C.). This multi-criteria comparative evaluation demonstrates the merits of single-stage isolated AC–DC submodules over the conventional two-stage isolated AC–DC submodules, and reveals that the direct matrix-based dual-active-bridge (MB-DAB) type submodule is the most pertinent power conversion topology for cascaded modular isolated MVAC-LVDC power conversion application. • An initial discussion is provided on existing solutions related to grid-connected MVAC-LVDC conversion. • A brief description is provided on the shortcomings of the LFT based conversion solutions. • Subsequently, the various categories of isolated power-electronic conversion solutions are discussed based on modularity. • A qualitative comparison of the isolated power-electronics based conversion solutions reveals the merits of the cascaded modular conversion strategy. • Comprehensive descriptions for each of the available single-phase isolated AC–DC conversion submodules in the literature are provided. • A quantitative comparative evaluation of MVAC-LVDC isolated converter's 3-phase submodule possibilities and LFT-based MVAC-LVDC solution is presented. • The comparison criteria are efficiency (η), power density (ρ), cost (σ), failure rate (λ), number of components (NoC) and control complexity (C.C). • This multi-criteria comparative evaluation demonstrates that a direct matrix-based dual-active-bridge (MB-DAB) type submodule is the most suitable topology. [ABSTRACT FROM AUTHOR]

In this paper, a model-based approach is proposed to detect and diagnose stator winding fault in the Brushless wound-field synchronous generator (BWFSG). The extended Kalman filter is used as a state and parameter estimation technique for the proposed model-based approach. The mathematical model of the BWFSG with stator winding fault is developed and simplified for online implementation. An experimental test-rig is used to acquire the required inputs for the developed state estimation technique. The estimated rotor currents and fault parameter are analyzed to identify key signatures for condition monitoring (CM). The harmonic components such as the second harmonic components of the estimated field and damper currents, and the rms value of the estimated fault parameters are identified as suitable signatures for winding fault and diagnose. Based on the identified signatures, a model-based CM algorithm is proposed and validated in real time. The validation results confirmed that the proposed algorithm is able to detect and diagnose winding inter-turn short-circuit faults in real-time reliably. [ABSTRACT FROM PUBLISHER]

Cowpea ( Vigna unguiculata L. Walp) is an important grain legume cultivated in drought-prone parts of the world, having higher tolerance to heat and drought than many other crops. The transcription factor, Dehydration-Responsive Element-Binding protein 2A (DREB2A), controls expression of many genes involved in osmotic and heat stress responses of plants. In Arabidopsis , DREB2A-interacting proteins (DRIPs), which function as E3 ubiquitin ligases (EC 6.3.2.19), regulate the stability of DREB2A by targeting it for proteasome-mediated degradation. In this study, we cloned the cowpea ortholog of DRIP ( VuDRIP ) using PCR based methods. The 1614 bp long VuDRIP mRNA encoded a protein of 433 amino acids having a C3HC4-type Really Interesting New Gene (RING) domain in the N-terminus and a C-terminal conserved region, similar to Arabidopsis DRIP1 and DRIP2. We found VuDRIP up-regulation in response to various abiotic stresses and phytohormones. Using yeast ( Saccharomyces cerevisae ) two-hybrid analysis, VuDRIP was identified as a VuDREB2A-interacting protein. The results indicate negative regulation of VuDREB2A by ubiquitin ligases in cowpea similar to Arabidopsis along with their other unknown roles in stress and hormone signaling pathways. [ABSTRACT FROM AUTHOR]

In this paper, a hybrid of indoor ambient light and thermal energy harvesting scheme that uses only one power management circuit to condition the combined output power harvested from both energy sources is proposed to extend the lifetime of the wireless sensor node. By avoiding the use of individual power management circuits for multiple energy sources, the number of components used in the hybrid energy harvesting (HEH) system is reduced and the system form factor, cost and power losses are thus reduced. An efficient microcontroller-based ultra low power management circuit with fixed voltage reference based maximum power point tracking is implemented with closed-loop voltage feedback control to ensure near maximum power transfer from the two energy sources to its connected electronic load over a wide range of operating conditions. From the experimental test results obtained, an average electrical power of 621 \mu\W is harvested by the optimized HEH system at an average indoor solar irradiance of 1010 lux and a thermal gradient of 10 K, which is almost triple of that can be obtained with conventional single-source thermal energy harvesting method. [ABSTRACT FROM AUTHOR]

The satellite-based remote sensing technique has been widely used in monitoring wildfire spread. There are two prominent drawbacks with this approach of using satellites located in space: 1) very low sampling rate (temporal resolution problem) and 2) lack of accuracy (spatial and spectral resolution problem). To address these challenges, a wireless sensor network deployed at ground level with high-fidelity and low-altitude atmospheric sensing for wind speed of local wildfire spread has been used. An indirect approach in sensing wind speed has been proposed in this paper as an alternative to the bulky conventional wind anemometer to save cost and space. The wind speed is sensed by measuring the equivalent electrical output voltage of the wind turbine generator (WTG). The percentage error in the wind speed measurement using the proposed indirect method is measured to be well within the \pm4% limit with respect to wind anemometer accuracy. The same WTG also functions as a wind energy harvesting (WEH) system to convert the available wind energy into electrical energy to sustain the operation of the wireless sensor node. The experimental results show that the designed WEH system is able to harvest an average electrical power of 7.7 mW at an average wind speed of 3.62 m/s for powering the operation of the wireless sensor node that consumes 3.5 mW for predicting the wildfire spread. Based on the sensed wind speed information, the fire control management system determines the spreading condition of the wildfire, and an adequate fire suppression action can be performed by the fire-fighting experts. [ABSTRACT FROM AUTHOR]

Drought stress affects the growth and productivity of the tea plant. However, the damage caused is not permanent. The present investigation studies the effect of CaCl on antioxidative responses of tea during post-drought recovery. Increase in dry mass, proline and phenolic content of leaf with decrease in HO and lipid peroxidation and increased activities of enzymes such as SOD, CAT, POX and GR in response to increased foliar CaCl concentration are indications for the recovery of stress-induced oxidative damage and thus improving post-stress recovery potential of Camellia sinensis genotypes. [ABSTRACT FROM AUTHOR]

This paper presents an optimized wind energy harvesting (WEH) system that uses a specially designed ultra-low-power-management circuit for sustaining the operation of a wireless sensor node. The proposed power management circuit has two distinct features: 1) an active rectifier using MOSFETs for rectifying the low amplitude ac voltage generated by the wind turbine generator under low wind speed condition efficiently and 2) a dc–dc boost converter with resistor emulation algorithm to perform maximum power point tracking (MPPT) under varying wind-speed conditions. As compared to the conventional diode-bridge rectifier, it is shown that the efficiency of the active rectifier with a low input voltage of 1.2 V has been increased from 40% to 70% due to the significant reduction in the ON-state voltage drop (from 0.6 to 0.15 V) across each pair of MOSFETs used. The proposed robust low-power microcontroller-based resistance emulator is implemented with closed-loop resistance feedback control to ensure close impedance matching between the source and the load, resulting in an efficient power conversion. From the experimental test results obtained, an average electrical power of 7.86 mW is harvested by the optimized WEH system at an average wind speed of 3.62 m/s, which is almost four times higher than the conventional energy harvesting method without using the MPPT. [ABSTRACT FROM AUTHOR]

Abstract: The mechanism by which Zn promotes Cu toxicity in duckweed Spirodela polyrhiza L. was investigated in order to understand the possible interaction between these two metals. Cu uptake was gradually declined by Zn. The induction of oxidative stress is shown by increased levels of lipid peroxidation, total peroxide, superoxide anion and lipoxygenase activity. Zn interaction reduced the oxidative damage. However, only Zn-treated plants did not show alteration in the above observed parameters. The activities of antioxidant enzymes catalase, ascorbate peroxidase and peroxidase showed a very high increase in activity in Cu+Zn treatment as compared to Cu or Zn alone-treated plants. Thus, this study demonstrates that zinc reversed the effect of copper, combating against Cu induced oxidative damage and improvement of duckweed''s growth and toxicity under natural condition. [Copyright &y& Elsevier]

Abstract: The effects of increasing concentrations of copper on the growth, ultra-structure and on certain biochemical parameters of water lettuce (Pistia stratiotes L.) were investigated under controlled conditions in the nutrient solutions containing increased copper sulfate concentrations ranging from 0 to 100 μM. Copper treatment for 12, 18 or 24 h resulted in inhibition of roots and leaves dry biomass. Atomic absorption spectrometry analysis of roots and leaves showed that copper accumulation increased with increase in concentration and duration of metal treatment. It is seen that copper resulted in increased production of hydrogen peroxide and superoxide radical in both roots and leave cells, showed a significant change after 24 h of treatment. Also, the significant decrease in the contents of total protein and photosynthetic pigments was observed. The antioxidant enzymes, viz., peroxidase (POX, E.C.1.11.1.7), catalase (CAT, E.C.1.11.1.6) and superoxide dismutase (SOD, E.C.1.15.1.1) showed significant variation with the increase in lipid peroxidation. Increasing trends was observed in levels of ascorbate and glutathione. The rapid inducibility of some of these enzymes are useful early and sensitive indicators of heavy metal toxicity. The results demonstrated that exposure to elevated concentration of Cu had a remarkable effect on the biochemistry and physiology, induced oxidative stress in water lettuce characterized by the initiation of lipid peroxidation that inhibited growth and disintegration of major antioxidant systems. To cite this article: R.K. Upadhyay, S.K. Panda, C. R. Biologies 332 (2009). [Copyright &y& Elsevier]

Abstract: The present investigation was undertaken to verify whether mitochondria play a significant role in aluminium (Al) toxicity, using the mitochondria isolated from tobacco cells (Nicotiana tabacum, non-chlorophyllic cell line SL) under Al stress. An inhibition of respiration was observed in terms of state-III, state-IV, succinate-dependent, alternative oxidase (AOX)-pathway capacity and cytochrome (CYT)-pathway capacity, respectively, in the mitochondria isolated from tobacco cells subjected to Al stress for 18 h. In accordance with the respiratory inhibition, the mitochondrial ATP content showed a significant decrease under Al treatment. An enhancement of reactive oxygen species (ROS) production under state-III respiration was observed in the mitochondria isolated from Al-treated cells, which would create an oxidative stress situation. The opening of mitochondrial permeability transition pore (MPTP) was seen more extensively in mitochondria isolated from Al-treated cells than in those isolated from control cells. This was Ca2+ dependent and well modulated by dithioerythritol (DTE) and Pi, but insensitive to cyclosporine A (CsA). The collapse of inner mitochondrial membrane potential () was also observed with a release of cytochrome c from mitochondria. A great decrease in the ATP content was also seen under Al stress. Transmission electron microscopy analysis of Al-treated cells also corroborated our biochemical data with distortion in membrane architecture in mitochondria. TUNEL-positive nuclei in Al-treated cells strongly indicated the occurrence of nuclear fragmentation. From the above study, it was concluded that Al toxicity affects severely the mitochondrial respiratory functions and alters the redox status studied in vitro and also the internal structure, which seems to cause finally cell death in tobacco cells. To cite this article: S.K. Panda et al., C. R. Biologies 331 (2008). [Copyright &y& Elsevier]

Summary: Oxidative stress and ultrastructural changes under hexavalent chromium stress were investigated in developing rice seedlings. Chromium treatment for 24 or 48h resulted in inhibition of root length and dry biomass. Atomic absorption spectrometry analysis of roots showed that chromium accumulation increased with increase in concentration and duration of metal treatment. Chromium resulted in increased production of hydrogen peroxide and superoxide radical in root cells, which was a significant change after 48h of treatment. Time-course analysis of malondialdehyde content showed no substantial variation during early treatment periods (2, 6 or 12h). Increase in malondialdehyde content was observed only after 18h and it continued to increase until 48h after treatment. Loss of membrane integrity, analyzed in terms of Evans blue uptake in root cells, showed an increase in uptake of the reagent, indicating loss of membrane integrity. The antioxidant enzyme, viz., guaiacol peroxidase, was least affected, while glutathione reductase showed significant decline after 24 or 48h of metal treatment, followed by increased activity of superoxide dismutase. The level of ascorbate was not affected by chromium, while an increase in the level of glutathione was observed. At the ultrastructural level, potential damage to the root cell was noted after 48h at 100μM of chromium compared with controls. [Copyright &y& Elsevier]

Aluminum being the third most abundant metal in the earth's crust poses a serious threat to crop productivity in acid soils, which comprise almost half of the arabIe land. This review travels across time and updates research done on aluminum stress in plants. In its phytotoxic forms, aluminum affects root growth by acting in the root apical zone, resulting in growth inhibition in a very short time at micromolar concentrations. The mechanisms of aluminum toxicity in plants may proceed by growth inhibition, callose accumulation, cytoskeletal distortion, disturbance of plasma membrane surface charge, and W-ATPase activity, lipid peroxidation of membranes, production of reactive oxygen species in cytosol and mitochondria, respiratory dysfunction, opening of mitochondrial permeability transition pores, collapsing of inner mitochondrial membrane potential, activation of mitochondrial protease, and induction of nuclear apoptosis, resulting ultimately in programmed cell death. In contrast, the mechanism of tolerance involves the exudation of organic acid anions, complexation of aluminum with organic acids, and subsequent detoxification. Many oxidative stress genes and other metabolically important genes have also been found to be induced under aluminum stress, and overexpression analyses have also shown some plants to develop some degree of tolerance. In the future, researchers in the area of aluminum research should investigate more basic mechanisms of aluminum toxicity and discover and study more aluminum-responsive genes that confer resistance against this toxic metal, to ensure food security for ever-increasing human populations in the future. [ABSTRACT FROM AUTHOR]

Aquatic weed (Spirodela polyrhiza L.) was acclimatized to NaCl solutions of various levels of salinity. A uniform decrease in catalase activity suggested a loss of hydrogen peroxide detoxification ability. On the other hand, an increase in superoxide dismutase, guaiacol peroxidase, and glutathione reductase supported the existence of a biochemical defense mechanism against free radicals generated during exposure to short-term salinity stress. However, lipid peroxidation and total peroxide content increased with increasing salt stress imposition. These results suggest peroxidative degradation of membrane lipids in the root cells exposed to high salinity stress. A higher accumulation of proline at higher concentrations was assessed, implicating proline as avoiding water deficit and stabilizing cell membranes and proteins. [ABSTRACT FROM AUTHOR]

Over the past decade, cyberattack events on the electricity grid are rising and have severely impacted grid operation. These attacks are becoming more intelligent as they can falsify critical data and bypass existing protection protocols. This could result in the system to operate in a nonoptimal condition and suffer substantial economic losses over a prolonged period. Hence, it is crucial to develop tools to defend the system against such attacks to minimize the cost of malicious operations. This article aims to develop a novel command authentication strategy to detect and mitigate false data injection attacks (FDIAs) targeting the system centralized economic dispatch (ED) control signals. First, we describe the ED problem based on Singapore’s deregulated market context. We then perform a risk assessment and formulate a stealthy FDIA vector targeting the ED control signals. Subsequently, we propose a novel authentication technique leveraging on the multiagent system, which includes detection and mitigation algorithms to verify the ED control commands. Last, we evaluate the efficiency and latency of the proposed technique on the 5-bus, 3-generating unit, and 15-generating unit test system. Simulation and experiment results using a real-time hardware-in-the-loop system proves that the authentication technique can detect and mitigate the stealthy FDIA vector with high accuracy. [ABSTRACT FROM AUTHOR]

Grid impedance has a significant impact on the small-signal stability and control of grid-connected power converters used for connecting multiple distributed energy resources and in various motor drive applications. To apply advanced control schemes, such as adaptive control, real-time grid impedance is a necessary parameter that ensures stability margins of the system during operation. For real-time grid-impedance measurement purpose, broadband frequency-response measurement techniques based on the pseudorandom binary sequence can be used. In this article, a computationally effective perturbation signal quadratic residue binary (QRB) sequence is proposed for real-time grid impedance measurement. Unlike the conventional perturbation signals, the QRB sequence has low crest factor and less perturbation duration resulting in minimal disturbance during impedance measurement. To extract the grid impedance in real-time, the QRB sequence is added to the reference d-axis and q-axis currents of the battery energy storage system (BESS). Next, perturbed voltage and current signals are extracted in the abc-frame and converted to the d-q-frame, and grid impedance is assessed. Subsequently, the system stability is analyzed using the generalized Nyquist stability criterion. Later, an adaptive control algorithm is proposed and applied to the energy storage system (ESS) to enhance stability margins of the system based on the measured grid impedance. The effectiveness of the proposed perturbation sequence for impedance measurement and stability improvement algorithm are tested on a standard CIGRE microgrid system in the MATLAB/Simulink simulation environment. Experiments are conducted on a reduced scale 3 kVA laboratory testbed and results are presented to validate the efficacy of the proposed perturbation sequence and stability improvement algorithm. [ABSTRACT FROM AUTHOR]

Though the merits of matrix-based dual-active-bridge (MB-DAB) ac–dc converter as a submodule for grid-connected multilevel medium-voltage ac (MVac)–low-voltage dc (LVdc) conversion have been presented in recent literature, its operational challenges in the cascaded configuration have not been explored. The objective of this article is to present the inevitable challenge of unequal power routing through the submodules of cascaded matrix-based dual-active-bridge (CMB-DAB) and its mitigation. The detailed and simplified small-signal model of the CMB-DAB converter along with the proposed power balance control (PBC) strategy required to eliminate the power imbalance issue are explained comprehensively. The simulation results for a 3-cell 52.65-kVA CMB-DAB converter along with scaled-down 5.85 kVA experimental results are presented, to demonstrate the unavoidable power imbalance issue and the proposed PBC strategy as a mitigation technique. The proposed scheme is observed to perform seamlessly with the conventional LVdc bus voltage control and remediate power-routing imbalance issue during the steady-state, load-change and hot plug-in/hot plug-out operations. [ABSTRACT FROM AUTHOR]

The cascaded H-bridge (CHB) multilevel converter has been used in various applications, such as the STATCOMs and solid-state transformers. Due to its modular structure, fault tolerance can be incorporated in the CHB multilevel converter. In this article, a model predictive control (MPC)-based fault detection and localization (FDL) scheme is proposed for the CHB multilevel converter that utilizes the already-installed ac current measurement and does not require additional sensors. The proposed FDL scheme can detect single or multiple open-circuit switch faults in the CHB multilevel converter by comparing the predicted states of the MPC controller with the actual measured states. The detected fault(s) is(are) further localized through a fault localization matrix which narrows down the faulty switch using historical fault data. The proposed scheme is shown to complete the FDL process for both single or multiple open-switch faults within a fundamental cycle period, even during low-load conditions. It has also been shown that the proposed scheme is immune to system dynamics such as load and voltage variations, and has been validated experimentally for various open-circuit fault scenarios. [ABSTRACT FROM AUTHOR]

In this article, a new circulating current control architecture is proposed to suppress the submodule capacitor voltage ripple in a modular multilevel converter (MMC). The proposed cascaded control architecture uses the spatial repetitive controller (SRC) in both the outer voltage loop and the inner current loop, and can effectively suppress the second harmonic component of the submodule capacitor voltage ripple even under variable line frequency conditions. The dual SRC-based circulating current controller injects a second harmonic component into the circulating current to suppress the submodule capacitor voltage ripple. The SRC, which is a frequency-adaptive periodic digital controller, incorporates a phase sampling technique to achieve dynamic change in the sampling frequency, can adaptively tune its gain characteristics according to operating line frequency of the MMC. Unlike the existing techniques, the proposed controller uses the submodule capacitor voltage information for circulating current harmonic reference generation and, hence, does not require additional sensing of the output current. Detailed mathematical analysis and architecture of the proposed controller are presented in this article. A 400-V, 1-kW MMC laboratory prototype is developed and experimental results demonstrating the performance of the proposed circulating current control architecture for variable frequency and load conditions are also presented. [ABSTRACT FROM AUTHOR]

Tea plant is best known as an economically important crop, environment hardy and an Al hyper accumulator. North East India forms one of the largest tea producing regions of the world but 90% of its soil is acidic need. Acidic soil has got major influence on overall crop production, hence it is of utmost necessity to understand the mechanisms of tea plant to adapt to such inhospitable conditions. Through this present investigation we try to understand the changes after exposure to various Al concentrations in TS462 clone of Camellia sinensis [L.] in hydroponic solution. The repercussions were measured in terms of generation of reactive oxygen species (ROS) and anti-oxidative enzyme activity in both root and shoot tissues of tea plant. When rooted tea cuttings were raised in hydroponic culture containing 50µm, 250µm and 500µm of Al for 60 days, a constant increase in uptake of Al by roots with the increase dose was observed. The increase in Al uptake with dose, corroborated with the production of super oxide anion (O2 -) hydrogen peroxide (H2O2) and malondialdehyde (MDA). These all repercussions led to an increment in activity of antioxidant machinery during the study showing that better antioxidative response is behind the relatively better tolerance capability of tea plants. [ABSTRACT FROM AUTHOR]

There has been increasing interest in solid-state transformers (SSTs) as a future replacement for conventional distribution transformers as it is able to provide ancillary services in addition to step-up/step-down of voltages. In SSTs, a common topology used in the ac–dc stage is the cascaded H-bridge (CHB) multilevel converter. This paper proposes a novel dual-model predictive control method for the CHB multilevel converter with faster dynamic response, improved harmonic performance, and voltage balancing of the CHB cells. The primary model enables conventional control over source current and output voltages, whereas the secondary model is able to generate the reference source current through power modeling, which eliminates the need for a proportion-integral (PI) controller, thus resulting in faster dynamic response. A Luenberger-based observer is also implemented to estimate the dc load current in each CHB cell. The second-order harmonic notch filter and the CHB cell dc voltage balancing cost function aim at improving the performance of the source current and CHB cell dc voltages, respectively. The proposed control techniques are then validated under steady-state and transient conditions through simulation and experiment with a laboratory prototype. [ABSTRACT FROM AUTHOR]

Electrical grid's modernization and the need for sustainable sources of energy lead to changes in physical infrastructure and subsequent operations of the grid, such as penetration of renewables and local power generation from them. There is a shift in paradigm from remotely concentrated generation toward distributed generations that are local to the loads. To meet the objective of sustainability, the local generations must include renewable energy conversions. This requires power-flow management of power variability arising from the spatial and temporal characteristics of the renewables like solar energy. Such management must require least human intervention, and it is achievable through fast and reliable automations. This paper presents geographic information system integrated automation of a noniterative power-flow method known as holomorphic embedded power flow (HEPF), thereby providing local grids the ability to manage themselves. Since HEPF reliably guarantees the solution and reaches it very fast through constructing the solution, it is an ideal candidate for near real-time updates of the electrical states of a power system. The role of the HEPF as a key enabler for the services of a power-flow manager, that performs optimizations for a cluster of buildings, is then illustrated. [ABSTRACT FROM AUTHOR]

The nine-switch converter is a multiport converter having two three-phase terminals and a dc-link, just like a 12-switch back-to-back (BTB) converter, but with 25% reduction of active switch count. However, the reduction from 12-switch to 9-switch may not always be an efficient choice considering losses in the switches. Only the load–source combination for the ac–ac common frequency mode and the source–source combination for the ac–dc different frequency (ac–dc DF) mode have been reported, so far, to yield relatively lower loss for the nine-switch converter. This paper shows that the nine-switch converter can have relatively lower loss even with a load–source combination, instead of only source–source combination in its ac–dc DF mode—when the upper terminal is connected to a dc load and the lower terminal is connected to an ac source. Mathematical proof is presented with derivation of the particular operating parameters for which the nine-switch converter will have comparatively lower losses. The analysis is validated with simulation and experimental results of a 1-kW system. Finally, the benchmark of the application criteria of the nine-switch converter for having lower conduction loss than the BTB converter is updated in this paper. [ABSTRACT FROM AUTHOR]

This paper proposes a modified proportional resonant (PR) based control scheme for a three-level Vienna rectifier that reduces the input current harmonic distortion [total harmonic distortion (THD)] for harmonic contaminated and unbalanced supply voltage conditions. Low-order current harmonics that are present in the source side currents can be selectively eliminated using this proposed control strategy. In addition, the complete control technique includes the proportional integral (PI) based voltage balancing technique to balance the output voltages of the Vienna rectifier. This method includes the advantages of both hysteresis-based current control (fast transient response) and PI-based vector control (fixed frequency operation) methods. Various computational blocks such as space vector modulation (SVM) block, current/voltage transformation blocks, etc., are not necessary to implement this control method. Therefore, this scheme is relatively easy to implement using inexpensive digital controllers. A 1-kW prototype of the rectifier is built and tested in the laboratory environment using the proposed control method. The converter provides a unity power factor operation with low-current THD at the input side, balances the capacitor voltages, and tracks the voltage reference at the output side. [ABSTRACT FROM AUTHOR]

Evolutionary processes have evolved plants to cope with several different natural stresses. Basic physiological activities of crop plants are significantly harmed by these stresses, reducing productivity and eventually leading to death. The recent advancements in high-throughput sequencing of transcriptome and expression profiling with NGS techniques lead to the innovation of various RNAs which do not code for proteins, more specifically long non-coding RNAs (lncRNAs), undergirding regulate growth, development, and the plant defence mechanism transcriptionally under stress situations. LncRNAs are a diverse set of RNAs that play key roles in various biological processes at the level of transcription, post-transcription, and epigenetics. These are thought to serve crucial functions in plant immunity and response to changes in the environment. In plants, however, just a few lncRNAs have been functionally identified. In this review, we will address recent advancements in comprehending lncRNA regulatory functions, focusing on the expanding involvement of lncRNAs in modulating environmental stress responsiveness in plants. • Long non coding RNA, Abiotic and Biotic stress, stress regulation. [ABSTRACT FROM AUTHOR]

This paper presents the analysis and design of an isolated high-voltage LLC resonant dc–dc full-bridge converter based on symmetrical quadrupler rectifier (SQR). Unlike conventional Cockcroft–Walton and full-bridge diode rectifiers, the SQR circuit provides significant improvement in power density by reducing the transformer turns-ratio without much increase in the output impedance. Moreover, the LLC converter can provide additional voltage boost, if operated, below the series resonant frequency of the LLC tank. The operating region of the converter is chosen in such a way that the converter always operates in ZVS for all line and load conditions with additional voltage boost. A new method based on basic differential equation is proposed for the accurate analysis and design of the converter and subsequently, the key results are compared with a first harmonic approximation based analysis method. A 120 V dc input, 2 kV output, 200 W laboratory prototype has been designed, built, and tested. Simulation and experimental results shown in this paper demonstrate the validity of the analysis and design of the presented converter. [ABSTRACT FROM AUTHOR]

In an asymmetrical pulse-width-modulated half-bridge (APWM HB) series resonant converter, an auxiliary LC network is provided for ensuring zero-voltage switching (ZVS) over a wide range of line and load variations. However, it comes at the cost of increased number of components and reduced efficiency and reliability. This paper presents a novel design methodology for the standard APWM HB resonant topology, which uses the magnetizing current and eliminates the need for extra components. The converter with the proposed design methodology operates at the resonant frequency of the tank and features load-independent ZVS for a wide range of input voltage variation with minimal magnetizing current. Empirical formulae are derived to design the resonant network and the magnetizing inductance of the high-frequency transformer systematically in a flowchart-based manner. The proposed design is validated by using simulations as well as experiments and is compared with a reference APWM HB series resonant converter design that uses an auxiliary LC circuit for ZVS. Two separate experimental prototypes of the two converters rated for 30 W, 48 V/5 V with a switching frequency of 500 kHz were built and tested in the laboratory. It was found that the converter with the proposed design methodology, apart from having lower component count, is about 3% more efficient than the reference topology at the rated power. [ABSTRACT FROM PUBLISHER]

Arsenic (As) stress greatly affects plant growth and production, threatening food security and also human health through the food chain. As alters various physiological processes that subsequently affect the normal metabolism in plants. The plants have evolved different mechanisms against stress, where nanoparticles (NPs) improve plant metabolism and the defence system, thereby alleviating As stress in it. This article dis- cusses the effects of As in plants at different levels, and the role of NPs in modulating the plant defence system against As stress. This article may help encourage future research on plant protective mechanisms against stress and the significance of NPs in plant science and agriculture. [ABSTRACT FROM AUTHOR]

• All three agents significantly improved stress tolerability in mustard plants. • Heavy metal attenuating capacity of ethanol and acetic acid depicted. • Putresciene pretreatment showed best tolerance closely followed by acetic acid. Rapid increase in the accumulation of Cd in plants interrupt with metabolism thus inhibiting the growth and development. Hence, finding a remedy for Cd detoxification and improvement of plant's tolerability to metal toxicity is crucial. In this report, we investigate the differential responses to putrescine (PU), ethanol (ET) and acetic acid (AA) on Cd toxicity in conditions of metal aggregation and stress permissiveness in Indian mustard (Brassica juncea L.). Brassica juncea seedlings (12 day-old) were dealt with Cd (0.5 mM CdCl 2) alone and in combinations of PU (0.5 mM), 0.3% and 0.6% of ET and AA (250 µM) in hydroponic culture for three days. The enhancement in Cd concentration in the plant system induced reduction in growth, biomass and chlorophyll content due to heightened oxidative damage (raised malondialdehyde, MDA content; hydrogen peroxide, H 2 O 2 level) and gradual decrease in antioxidant defense. Cd treatment along with application of PU, ET and AA enhances growth of the plants as quantitated by biomass; represses oxidative damage; increases ascorbate-glutathione (AsA-GSH) and the activities of antioxidant enzymes (superoxide dismutase, SOD; glutathione reductase, GR; glutathione-S-transferase, GST; catalase, CAT; guaciol peroxidase, POX; glutathione peroxidase, GPx; polyphenol peroxidase, PPO; ascorbate peroxidase, APx; monodehydroascorbate reducatase, MDHAR and dehydroascorbate reductase, DHAR. Results indicated that PU, ET and AA plays a vital role in mustard seedlings by mitigating Cd toxicity and increasing the stress tolerance, through upregulating the antioxidant defense systems. Amelioration of heavy metal stress by ET and AA is being reported for the first time in this report. Although PU has been found to be the best among the three the ameliorating capacity of PU and AA are almost similar. [ABSTRACT FROM AUTHOR]

Plants growing in alkaline soil are prone to iron (Fe) deficiency. Under the effect of Fe deficiency, plants produce high amounts of reactive oxygen species, which are toxic to plant tissues and cellular components. Antioxidant enzymes play a crucial role in protecting plants from the deleterious effect of Fe deficiency. Blackgram is extensively grown in India preferring loamy soils with pH 6.5–7.8 leading to Fe deficiency. In the present study, antioxidant responses of two contrasting blackgram cultivars, "Sonkush SB23-5" and "Manas SB32-13", have been studied under Fe deficiency. A significant decrease in growth and biomass was observed in stressed plants as compared to control. "Sonkush" recorded higher hydrogen peroxide and malondialdehyde contents. Maximum decline in catalase, ascorbate peroxidase, guaiacol peroxidase and polyphenol peroxidase activities was recorded for "Sonkush" in leaves and roots. An increase in superoxide dismutase content was positively correlated with ferric chelate reductase and negatively with other antioxidative enzymes under Fe deficiency. The antioxidative responses as observed for both cultivars infer that a part of their tolerance against Fe deficiency is contributed by antioxidants. However, the work also holds the potential for further studies to explore the other tolerance mechanisms included against the stress. [ABSTRACT FROM AUTHOR]

In this article, a new model-based fault detection and localization scheme is proposed for cascaded H-bridge (CHB) multilevel converter to localize the open-circuit faults without needing any additional sensors. The grid current is estimated from the gird voltage, switching states, and dc bus voltages, and compared with the measured grid current. Any significant deviations in the estimated and actual grid currents of the CHB trigger an open-circuit (OC) fault. Once the fault is detected, modulation scheme is switched from phase-shifted unipolar SPWM to phase-shifted bipolar sine pulse width modulation (SPWM) to localize the OC faults. At selected time instants, the change in measured grid current for a specific period is calculated and compared with the estimated change in grid current from the system model. The abovementioned comparisons are used to localize the OC faults in the CHB. The proposed method is validated on a scale-down CHB prototype developed in the laboratory environment, and experimental results are presented to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Previous studies of distributed power and network focused only on the optimization of either the microgrid load dispatch or reconfiguration power loss. Micorgrid economic load dispatch approach normally does not support distribution network. Network reconfiguration usually does not take distributed generators into consideration. Thus, it is necessary to integrate these two sub-problems together in order to benefit the whole network. In this paper, an integrated solution that takes care of both microgrid load dispatch and network reconfiguration is proposed. The stochastic nature of wind, PV and load is taken into consideration. The forecasting of the wind, PV and load data are considered. The four bio-inspired optimization schemes are adopted to solve the problem. The results obtained have shown that the four optimization techniques are all capable of solving this problem. By using the integrated approach, microgrid can be incorporated into the network more effectively. The network can adjust itself more efficiently to allow utilization of the renewable energy resources. [ABSTRACT FROM PUBLISHER]

The challenge in controlling a three-phase pulsewidth modulation (PWM) rectifier under balanced conditions arises from the fact that the state-space averaged model reported in literature has a multi-input-multi-output nonlinear structure and furthermore exhibits a nonminimum phase feature. In this paper, a simple single-input-single-output model is constructed by separating the d-axis and the q-axis dynamics through appropriate nonlinear feedforward decoupling while maintaining nearly unity power factor operation. With the proposed model, the nonminimum phase feature inherent in an ac-to-dc rectifier becomes a simple right- half-plane zero appearing in the small-signal control-to-output transfer function. In addition, the model exhibits a close similarity to a dc-dc boost converter under both large-signal and small-signal operating conditions. This makes it possible to extend the system analysis and control design techniques of dc-dc converters to the three-phase PWM rectifier also. The validity of the proposed model has been verified experimentally in the frequency domain under open-loop operation of the PWM rectifier. The usefulness of the model is further demonstrated through closed-loop operation of the rectifier with both voltage mode and inner-current-loop-based schemes. [ABSTRACT FROM AUTHOR]

Instantaneous power regulation is an effective way to improve the performance of a pulsewidth-modulation rectifier operating under unbalanced supply-voltage conditions. By properly setting current commands, this approach aims to achieve performance features that are normally achievable only under ideal balanced operating conditions. This paper proposes an instantaneous power-regulation strategy called output-power-control method, in which the current commands are determined so as to appropriately distribute the input power to maintain a constant dc output voltage and sinusoidal line currents. Although the power factor is not directly controlled, it is shown that the proposed scheme results in near unity vector power factor. The current commands are given by a set of simple linear equations in which the proposed control scheme can be easily implemented. Experimental results obtained with a 1-kW laboratory prototype demonstrate that the proposed scheme fulfils all the main objectives of a high-performance rectifier. [ABSTRACT FROM AUTHOR]

Flexibility in electricity demand can be leveraged for demand side management (DSM) to enable aspects such as “demand following generation” and provide ancillary services to support grid integration of renewable and distributed energy resources. The upcoming connected devices in demand centers such as commercial buildings and households may be leveraged for this. However, the coordination among distributed demand centers in a scalable decentralized manner to achieve DSM objectives is still a challenge. In this article, a generalized hierarchical transactive energy based multiagent framework is proposed. This framework includes energy management demand agents (EMDAs) at the building level, which coordinate the operation of different appliances within the buildings. EMDAs also actively participate on day-ahead Walrasian market at the cluster of buildings level. In this market, the effect of wide-adoption of DSM on generation dispatch is also studied. A particular instance of this framework is also implemented in a cyber-test system consisting of standard industrial microcontroller platforms to emulate practical implementations via smart meters. Experimental results of the proposed system are included to demonstrate the possibility of avoiding disptach from expensive generation units by reduction in peak demand and providing demand response inherently. [ABSTRACT FROM AUTHOR]

Expression pattern of aluminum (Al) tolerance genes is one of the major determinants of Al avoidance/tolerance within plant cultivars. We have performed transcriptome analysis of two contrasting (Al-tolerant, Disang; Al-sensitive, Joymati) cultivars of India's North Eastern region, an indica rice diversity hotspot, on exposure to excess Al3+ treatment in acidic condition. Co-expression analysis and SNPs enrichment analysis proposed the role of both trans-acting and cis-acting polymorphisms in Al signaling in the Al-tolerant cultivar. We proposed ten major genes, including arginine decarboxylase, phytase, and beta-glucosidase aggregating factor as candidates responsible for Al tolerance based on transcriptome analysis. Al3+ stress led to changes in the alternative splicing profile of the Al-tolerant cultivar. These studies demonstrated the transcriptional variations affiliated to Al avoidance/tolerance in contrasting indica rice of North East India and provided us with several candidate genes responsible for Al tolerance. [ABSTRACT FROM AUTHOR]

To utilize the solar photovoltaic (PV) energy efficiently, dc–dc converters are widely used in both grid-connected and stand-alone systems. Among the various topologies, interleaved dc–dc boost converter offers the benefit of modularity, high power density, and high efficiency along with reduced input current ripple to the PV panel, thereby improving its power extraction efficiency. Open-circuit faults in any of the semiconductor switches of interleaved boost converter could lead to unequal loading on the healthy phases and increase in ripple current that reduces the extraction efficiency of the PV system. To address this issue, a new fault detection and localization scheme is proposed in this article. The proposed scheme utilizes the switching-frequency-based harmonic component for fault detection and localization. Once the fault is localized, a postfault restoration and control strategy is also proposed to ensure equal current sharing among the remaining healthy modules within their maximum current rating and minimize the input current ripple in the PV panel. Detailed simulations are carried out to show the effectiveness of the proposed approach. A laboratory prototype of the interleaved converter is built to validate the proposed approach and experimental test results are provided. [ABSTRACT FROM AUTHOR]

Iron (Fe) toxicity is a major challenge for plant cultivation in acidic waterlogged soil environments, where lowland rice is a major staple food crop. Only few studies have addressed the molecular characterization of excess Fe tolerance in rice, and these highlight different mechanisms for Fe tolerance. Out of 16 lowland rice varieties, we identified a pair of contrasting lines, Fe-tolerant Lachit and -susceptible Hacha. The two lines differed in their physiological and morphological responses to excess Fe, including leaf growth, leaf rolling, reactive oxygen species generation and Fe and metal contents. These responses were likely due to genetic origin as they were mirrored by differential gene expression patterns, obtained through RNA sequencing, and corresponding gene ontology term enrichment in tolerant vs. susceptible lines. Thirty-five genes of the metal homeostasis category, mainly root expressed, showed differential transcriptomic profiles suggestive of an induced tolerance mechanism. Twenty-two out of these 35 metal homeostasis genes were present in selection sweep genomic regions, in breeding signatures, and/or differentiated during rice domestication. These findings suggest that Fe excess tolerance is an important trait in the domestication of lowland rice, and the identified genes may further serve to design the targeted Fe tolerance breeding of rice crops. [ABSTRACT FROM AUTHOR]

Iron (Fe) toxicity is one of the major abiotic stresses which limits the yield of lowland rice. This study aims to investigate the physiological, biochemical, and molecular aspects of two contrasting aromatic Joha rice, viz., Keteki and Kola Joha of Assam. Oxidative damage caused due to Fe2+ toxicity was quantitatively determined. Fe2+ toxicity in the growth medium increases the level of ROS and anti-oxidative enzyme activity. Along with the aforementioned damage caused due to Fe2+ toxicity, chlorophyll content decreases in both the rice varieties. Detection of Fe3+ and Fe2+ was also conducted by Perls' Prussian and Turnbull blue method, respectively. In addition, spectrophotometric quantification of Fe2+ was determined by 2, 2′-Bipyridyl (Bpy). Above 2.5 mM, Fe2+ toxicity was found to be lethal in rice seedlings affecting their total growth and biomass. Gene expression analysis of iron-regulated transporter 1 (OsIRT1), Yellow Stripe-Like 15 (OsYSL15), and ferritin 1 (OsFer1) revealed the differential gene expression over a time period of Fe2+ toxicity. Our study suggested that the different parameters which are considered here can be helpful for the better understanding of how aromatic Joha rice performed under Fe2+ toxicity which can also help to reveal broader aspects that how gene players are involved in the iron homeostasis mechanism in Joha rice in coming future. [ABSTRACT FROM AUTHOR]

Fluoride exporter genes (FEX) are known for the expulsion of cytoplasmic fluoride, thus preventing fluoride toxicity in plants. In this study, 31 FEX genes were identified across 19 plant species. Camphor Resistance (CrcB) domain was found to be present in all the identified FEX genes in plants. FEX genes were sequentially very conserved among the plants and are located mostly in chloroplast and mitochondria. The tertiary structure (3D) of AtFEX1 suggests that FEX genes of plants possess pore I and pore II, necessary for fluoride export. The TTFSGWNQ and GCLSTVSTF motifs were found to be well conserved in pore I and pore II. Phenylalanine (Phe/F) was also present in both the motifs, necessary for fluoride ions recognition and export. Cis-acting analysis in promoter sequences of plant FEX revealed several elements associated with various functions such as phytohormone signaling, integrating biotic and abiotic stress responses in plants. Prolong fluoride exposure causes necrosis in young leaves in Vigna radiata. Expression of VrFEX1 and VrFEX2 were highly induced under exogenous fluoride, thus suggesting a possible role in fluoride detoxification. [ABSTRACT FROM AUTHOR]

Electrical plug loads and appliances have evolved over time to provide sophisticated functions to occupants in a building, and they account for a big share of building's energy consumption. Despite their evolution, they are still unmanageable in commercial and industrial buildings, unlike lighting or air conditioning that are fixed infrastructures managed by an intelligent software layer, such as a building management system. The qualities of heterogeneity, numerosity, spatial irregularity, and displaceability have impeded efficient management of plug loads, unless they are appropriately identified in real time. Decades of efforts in both intrusive and nonintrusive load monitoring have not yielded any sufficiently reliable universal mechanism to identify plug loads. In this article, a practical method of uniquely identifying plug loads using a novel socket cyber-physical system is proposed. This socket/receptacle can access the metadata and operational data of plug loads in an automated fashion, thus yielding a live digital profile of plug loads connected to sockets. Based on acquired intelligence, a supervisory control system can contextually identify the plug loads to provide several digitalized services. Various benefits and use cases of the proposed smart cyber-physical system are explained, inclusive of improvement in operational energy efficiency of plug loads. [ABSTRACT FROM AUTHOR]

Rooftop and building-integrated distributed photovoltaic (PV) systems are emerging as key technologies for smart building applications. This paper presents the design methodology, mathematical analysis, simulation study, and experimental validation of a digital twin approach for fault diagnosis. We develop a digital twin that estimates the measurable characteristic outputs of a PV energy conversion unit (PVECU) in real time. The PVECU constitutes a PV source and a source-level power converter. The fault diagnosis is performed by generating and evaluating an error residual vector, which is the difference between the estimated and measured outputs. A PV panel-level power converter prototype is built to demonstrate how the sensing, processing, and actuation capabilities of the converter can enable effective fault diagnosis in real time. The experimental results show detection and identification of ten different faults in the PVECU. The time to fault detection (FD) in the power converter and the electrical sensors is less than 290  $\mu$ s and the identification time is less than 4 ms. The time to FD and identification in the PV panel are less than 80 ms and 1.2 s, respectively. The proposed approach demonstrates higher fault sensitivity than that of existing approaches. It can diagnose a 20% drift in the electrical sensor gains and a 20% shading of a solar cell in the PV panel. [ABSTRACT FROM AUTHOR]