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The invention of doubly‐fed induction generator (DFIG) brings the wind energy one step ahead as renewable power generation. But the performance of the grid‐connected DFIGs are greatly affected by grid disturbances as their stator windings are interfaced to the grid directly. Different fault current limiters are capable of improving fault ride through capability during short circuit faults. Nonlinear controller based fault current limiters (FCLs) are superior to deal with the nonlinearity of the power systems. This paper proposes a nonlinear adaptive backstepping controller (ABSC) based capacitive bridge‐type FCL (CBFCL) to enhance the fault ride through capability of a DFIG‐based wind farm connected to a multi‐machine power system. At first, a complete modelling of the CBFCL is derived to understand its behaviour during the normal and fault period more accurately. Then, the ABSC is designed based on that dynamic model, along with the backstepping controller (BSC) and sliding mode controller (SMC) for comparison purpose. Finally, the performance of the ABSC to control the CBFCL has been analysed and verified by comparing with that of the BSC and the sliding mode controller. All the graphical and mathematical analyses favour the ABSC based CBFCL under symmetrical and asymmetrical fault (both temporary and permanent) scenarios. [ABSTRACT FROM AUTHOR]

Summary: A nonlinear backstepping control scheme is proposed in this work for a bridge type fault current limiter (BFCL) in a hybrid power system for enhancing its transient performance. The hybrid power system has the provision to supply AC loads connected to the main grid and local DC loads. The DC‐side of that system is coupled with AC‐side through a bidirectional converter having power exchange capability between both AC‐ and DC‐sides. The AC‐side is coupled with the main grid through transmission lines and the BFCL is placed on the transmission line, where the faults are considered, as the transmission line is the most vulnerable point. The dynamical model of the BFCL is used to design the nonlinear backstepping controller (BSC) where the control input is derived in a way that it can ensure as well as enhance the transient performance of that hybrid power system. Lyapunov stability theory is used to theoretically demonstrate the stability of the BFCL using the proposed BSC. Theoretical findings guarantee the system stability, and simulation studies clearly indicate the superiority of the proposed BSC based BFCL (BSC‐BFCL), both graphically and numerically over an existing nonlinear sliding mode controller (SMC) for the BFCL (SMC‐BFCL), for symmetrical and unsymmetrical fault scenarios (both temporary and permanent type). In addition, percentage overshoot and settling time analyses suggest the lesser deviation of system responses during transients from their ideal values and quicker stability, respectively. Moreover, the astonishing total harmonic distortion (THD) values with the proposed technique signify the excellency over its competitors in every aspect. [ABSTRACT FROM AUTHOR]

Doubly-fed induction generators (DFIGs) have drawn prominent interest in the field of wind power generation, but they are vulnerable to grid faults. Grid codes mandate DFIGs to employ a sort of fault ride-through (FRT) technique during faults. Fault current limiters (FCLs) always help to augment the FRT capability of DFIGs and a non-linear controller boosts their performances. In this study, a non-linear auto-regressive moving average-L2 (NARMA-L2) controller-based bridge-type flux coupling non-superconducting FCL (BFC-NSFCL) is proposed to enhance the FRT capability of the wind farm. The authors analysed the performance of the proposed NARMA-L2-based BFC-NSFCL (NL2-BFC-NSFCL) against that of the conventionally used series dynamic braking resistor (SDBR), bridge-type FCL (BFCL), and proportional–integral (PI) controller-based BFC-NSFCL (PI-BFC-NSFCL). They tested the performance of the NL2-BFC-NSFCL through multiple temporary and permanent fault scenarios and carried out the mathematical and graphical analysis in MATLAB/Simulink platform. They found that the proposed NL2-BFC-NSFCL's performance surpasses the performances of the SDBR, the BFCL, and the PI-BFC-NSFCL. Moreover, the NL2-BFC-NSFCL has faster system recovery capability after the occurrence of any fault than other competitors. [ABSTRACT FROM AUTHOR]

The flow–sound interaction mechanism and its effect on the vortex dynamics in the wake of circular finned cylinders are experimentally investigated using phase-locked particle image velocimetry at Reynolds numbers between 7 × 104 and 9.5 × 104. In addition, a hybrid experimental–numerical technique using the theory of vortex sound is employed to quantify the acoustic sources and sinks in the vicinity of finned cylinders with different fin-to-root diameter ratios, Df/Dr = 1.5, 2.0, and 2.5. The results show that changing the diameter ratio of the fins induces fundamental changes in the wake structure and the vortex shedding process downstream of the cylinder. Finned cylinders induce stronger vortex cores with a shorter formation length compared to their equivalent bare cylinders. Moreover, the flow topology over the spanwise direction shows that acoustic resonance results in uniform cylindrical vortex cores with less three-dimensional distortion, which demonstrates that the flow field becomes highly two-dimensional during resonance excitation. Quantification of the energy transfer between the flow and the sound fields reveals an enhancement in the acoustic energy production closer to the cylinder with a significant dependence on its fin-to-root diameter ratio. [ABSTRACT FROM AUTHOR]

Abstract: Graphitic-C3N4/TiO2 nanocomposite was prepared as a photocatalyst (PC) active under visible light (λ ≥ 420 nm) by preparation of graphitic carbon nitride (g-C3N4) from melamine followed by an effective easy impregnation method. Several g-C3N4/TiO2 composites containing 1 to 12 wt% g-C3N4 were synthesized and characterized using X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential thermal analysis (DTA), photoluminescence (PL) spectroscopy, diffusion reflectance spectroscopy (DRS), and Brunauer-Emmett-Teller (BET) measurements. A photocatalytic mechanism is proposed based on the relative positions of the energy bands of the two constituents. Compared with its individual components, g-C3N4/TiO2 demonstrated unusually high photocatalytic activity for phenol decomposition in aqueous phase under visible-light irradiation. The heterojunction was optimized in the 5 wt% g-C3N4/TiO2 nanocomposite due to the well-matched bandgap structure (optimum loading) and excellent electron-hole pair separation in the conduction and valence band of TiO2 and g-C3N4, respectively. After 2 h of visible-light irradiation, 68 % degradation was observed when using this optimum composition. The performance was slightly decreased (to 66 %) after recycling of the catalyst four times (used a total of five times), but remained reliable for industrial applications considering other factors. In this system, TiO2 (Degussa P25) seems to play the principal PC role, while g-C3N4 acts as a sensitizer for absorption of visible light. Due to the enhanced visible-light absorption ability enabled by g-C3N4 in the composite, stable electron-hole (e−-h+) pairs produced at the interface of the heterojunction lead to generation of highly reactive free radicals (·O2, ·OH, etc.) which together initiate degradation of phenol but individually suffer from some limitation that must be overcome. The thermal stability and recycling efficiency of this PC will enable its use in industrial applications as a cost-effective sustainable cleanup candidate.Graphical abstract: The prepared g-C3N4/TiO2 exhibits stable electron-hole (e−-h+) pair separation at the heterojunction under visible light for enhanced degradation of organic pollutants via a redox mechanism. The g-C3N4 loading affects the photocatalytic activity, with the 5 wt% g-C3N4/TiO2 composite exhibiting the highest degradation, with recycling. [ABSTRACT FROM AUTHOR]

Bacterial blight (BB) is caused by Xanthomonas oryzae pv. oryzae ( Xoo ), a most destructive disease of rice, mostly in Asia, including Bangladesh. Altogether 96 isolates of Xoo were collected from 19 rice-growing districts of Bangladesh in both the rain-fed and irrigated seasons of 2014 to assess their pathotypic and genetic variation. Pathotypic analyses were carried out on a set of 12 Near Isogenic Lines (NILs) of rice containing a single resistance gene and two check varieties IR24 and TN1 by the leaf clipping inoculation method. A total of 24 pathotypes were identified based on their virulence patterns on the NILs tested. Among these, pathotypes VII, XII and XIV, considered as major, containing a maximum number of isolates (9.38% each), are frequently distributed in seven northern to mid-eastern districts of Bangladesh. The most virulent pathotype I was recorded in the Habiganj and Brahmanbaria districts. The molecular analysis of variability among the isolates was carried out through PCR analysis using multi-locus primers Jel1 and Jel2 (based on the repetitive element IS 1112 in the Xoo genome). Using the genotypic data, a dendrogram was constructed with 17 clusters along with 17 molecular haplotypes at the 65% similarity index. Cluster I was composed of 46 isolates considered as major, whereas clusters X, XI, XII and XVII were represented by a single isolate. A phenogram was constructed based on virulence to interpret the relationship between the pathotypes and the molecular haplotypes. At the 50% similarity level, among 10 clusters, cluster I, considered as major, consisted of a maximum of 10 pathotypes out of 24. In case of haplotypes, a maximum of 7 haplotypes were obtained from pathotype XII, whereas pathotypes IX, X, XV, XXII and XXIV were represented by a single haplotype. However, the present study revealed that different isolates belonging to the same pathotypes belonged to different haplotypes. Conversely, genetically similar haplotypes were also detected from different pathotypes collected from separate districts. This relationship appeared due to a high degree of DNA polymorphism among strains within many pathotypes existing in Bangladesh. [ABSTRACT FROM AUTHOR]

This paper proposes a double-integral sliding mode controller (DISMC) based bridge-type flux-coupling non-superconducting fault current limiter (BFC-NSFCL) to enhance the fault ride-through (FRT) capability of a DFIG-based wind farm connected to a multi-machine power system. At first, a complete modeling of the BFC-NSFCL is derived to understand its behavior during the normal and fault period more accurately. Then, the DISMC is designed based on that dynamic model obeying the double-integral theory, along with the single-integral sliding mode controller (SISMC) and non-integral sliding mode controller (NISMC) for comparison purpose. Finally, the performance of the DISMC in controlling the BFC-NSFCL has been analyzed and verified by comparing with that of the SISMC and the NISMC. The DISMC removes the chattering problems induced by the traditional SMCs and improves the transient performance by reducing the overshoot and steady-state error by implementing double-integral action. All the graphical and mathematical analyzes favor the DISMC based BFC-NSFCL under symmetrical and unsymmetrical fault (both temporary and permanent) scenarios. • Design dynamical modeling of a bridge-type flux-coupling non-superconducting FCL. • Design different sliding mode controllers for the BFC-NSFCL. • Propose the DISMC based BFC-NSFCL to enhance the FRT capability of a wind farm. • Reduce chattering problems induced by the traditional SMCs. • Ensure a better THD profile to improve the system performance. [ABSTRACT FROM AUTHOR]

Bacterial Blight (BB) caused byXanthomonas oryzaepv.oryzae(Xoo), a destructive disease of rice. Altogether, 96 isolates ofXoowere collected from 19 rice growing districts of Bangladesh in irrigated and rainfed seasons during 2014 to assess pathotypic variation. Pathotypic analyses on a set of 12 Near Isogenic Lines (NILs) of rice containing resistance genes viz.Xa1,Xa2,Xa3,Xa4,Xa5,Xa7,Xa8,Xa10,Xa11, Xa13,Xa14andXa21and two check varieties IR24 and TN1 by leaf clip-inoculation technique. A total of 24 pathotypes were identified based on their virulence patterns on NILs tested. Among these, pathotypes VII, XII, and XIV considered as major, containing maximum number of isolates, (9.38% each) frequently distributed in North to Mid-Eastern districts of Bangladesh. Most virulent pathotype I recorded from Habiganj and Brahmanbaria. This pathotypic variation explained the pathogenic relatedness ofX. oryzaepv.oryzaepopulations from diverse geographic areas in Bangladesh. [ABSTRACT FROM PUBLISHER]

Plant NADPH oxidases are key regulators of plant–microbe interactions and reactive oxygen species (ROS) are essential to plant defences against pathogens. A significant part in the role played by ROS has been ascribed to plant respiratory burst oxidase homologs (RBOHs). In potato ( Solanum tuberosum ), where RBOHs were previously shown to be involved in wound-induced oxidative burst, we assessed their expression after inoculation with Verticillium dahliae Kleb. and showed that StRbohA was the only homolog to be differentially induced in potato in response to inoculation. In order to investigate the potential role of this gene in plant protection against wilt diseases, we used Agrobacterium -mediated transformation of Arabidopsis to assess the effects of its overexpression on plant responses to V. dahliae . After inoculation with this pathogen, the transformed Arabidopsis line overexpressing StRbohA showed lower disease severity (percent damaged leaf area and vascular discoloration) as compared to the wild type. It also had higher ROS production and more cell death caused by hydrogen peroxide (H 2 O 2 ), compared to the wild type. Suberization of root cells was also more pronounced in the line overexpressing StRbohA , and supports a possible role for StRBOHA in plant resistance to V. dahliae . Together, these findings indicate that overexpressed StRbohA in Arabidopsis enhances the ROS-mediated defence mechanisms against V . dahliae and can be a potential tool to improve plant resistance to this and other soilborne pathogens that cause wilts in economically important crops. [ABSTRACT FROM AUTHOR]

A 900 MHz wearable beam steering antenna array is proposed. A wideband driven dipole when assisted by several varactor diode controlled parasitic dipoles allows the array beam to be steered in the azimuth. Antenna array prototypes fabricated using copper, conductive fabrics and conductive threads show good bandwidth and radiation performance. The array when placed against an anatomically correct human body model shows that the array beam can be steered along 3 distinct angles, 0, 45, and 315 degrees with 5.9 dBi peak gain. [ABSTRACT FROM PUBLISHER]

Inhalation exposure and beryllium (Be) toxicity are well-known, but research on bioaccessibility from soils via different exposure pathways is limited. This study examined soils from a legacy radioactive waste disposal site using in vitro ingestion (Solubility Bioaccessibility Research Consortium [SBRC], physiologically based extraction test [PBET], in vitro gastrointestinal [IVG]), inhalation (simulated epithelial lung fluid [SELF]) and dynamic two-stage bioaccessibility (TBAc) methods, as well as 0.43 M HNO 3 extraction. The results showed, 70 ± 4.8%, 56 ± 16.8% and 58 ± 5.7% of total Be were extracted (gastric phase [GP] + intestinal phase [IP]) in the SBRC, PBET, and IVG methods, respectively. Similar bioaccessibility of Be (~18%) in PBET-IP and SELF was due to chelating agents in the extractant. Moreover, TBAc–IP showed higher extraction (20.8 ± 2.0%) in comparison with the single-phase (SBRC–IP) result (4.8 ± 0.23%), suggesting increased Be bioaccessibility and toxicity in the gastrointestinal tract when the contamination derives from the inhalation route. The results suggested Be bioaccessibility depends on solution pH; time of extraction; soil reactive fractions (organic–inorganic); particle size, and the presence of chelating agents in the fluid. This study has significance for understanding Be bioaccessibility via different exposure routes and the application of risk-based management of Be-contaminated sites. [Display omitted] • Bioaccessibility of beryllium (Be) in soils by ingestion–inhalation was investigated. • Be bioaccessibility in the gastrointestinal phase of an in vitro assay was limited. • Higher bioaccessibility of Be in the GI tract via inhalation to ingestion exposure. • Organic matter regulated bioaccessibility at high pH and inorganic species at low pH. • pH, ligands, time, soil reactive fractions and particle size affected Be solubility. [ABSTRACT FROM AUTHOR]

The peak temperature rise in a high-resolution heterogeneous head model due to the electromagnetic energy absorption from wire and planar antennas are investigated within the frequency range of 900–6000 MHz. Electrically small nonresonant antennas, resonant antennas, and planar directive antennas are considered both radiating toward the direction of the head as well as away from the head. It is observed that the maximum temperature rise due to dipole antennas are between 0.17 and 4.07 °C for 1 W of input power for antenna to head separation distances between 5 and 20 mm. Planar antennas, e.g., planar inverted-F antennas and microstrip patches induce a peak temperature rise of 0.04–2.28 °C for 1 W depending on their orientations and distances from the head. Based on the directly simulated maximum temperature rise data an empirical formula is developed, which estimates the maximum temperature rise in the head as functions of antenna to head separation distance, operating frequency, and antenna free-space bandwidth. [ABSTRACT FROM PUBLISHER]

A novel internal antenna system is introduced for the GSM 1900 MHz frequency band which utilizes the electrically steerable parasitic array radiator (ESPAR) concept to steer the elevation plane beam in specific angular directions. The proposed antenna consists of a planar inverted-F antenna (PIFA) as the driven element and two inverted L antennas (ILAs) as parasitic elements. The ILAs are terminated with capacitive impedances at their bases. Full-wave analysis shows that the radiation beam can be scanned in space when the antenna is in free space as well as next to human head and hand phantoms. Measured results using varactor diodes controlling the base reactances show good return loss bandwidth. [ABSTRACT FROM PUBLISHER]

Xanthomonas oryzae pv. oryzae ( Xoo) is the causal agent of bacterial leaf blight of rice. In xanthomonads, HrpG (an OmpR family response regulator) and HrpX (an AraC-type transcriptional regulator) are the two key regulatory proteins required for regulation of hrp genes. Recently, we reported that an ORF XOO1662 encoding a putative leucine-rich protein (designated as LrpX) seems to be involved in pathogenicity but not in HR elicitation. Here, we report that LrpX is involved in negative regulation of a major hrp regulatory gene, hrpG, and of the genes in most of the hrp operons in Xoo. [ABSTRACT FROM AUTHOR]

Xanthomonas oryzae pv. oryzae ( Xoo) is the causal agent of bacterial leaf blight, a serious disease of rice. Here, we isolated a pathogenicity-deficient mutant of Xoo strain T7174R [a rifampicin-resistant derivative of T7174 (MAFF311018)] produced by in vivo insertion mutagenesis using the EZ::TN™ transposon system. This mutant, 74M2, was significantly reduced in virulence on rice cultivar IR24. From sequence analyses, the region with the EZ::TN transposon insertion was found to be in ORF XOO1662, one of the leucine-rich proteins found in the genome database for MAFF311018, which we have named lrpX. In planta growth of 74M2 was also slower than that of the wild type. A complementation construct for 74M2 restored both virulence and in planta growth to wild-type levels. The promoter region of lrpX contained a consensus plant-inducible promoter (PIP)-box (i.e., TTCGC-N15-TTCGC) commonly found in HrpX (an AraC-type transcriptional regulator)-regulon in xanthomonads. The HrpXo (HrpX of Xoo)-dependent expression of lrpX was confirmed using the fusion construct with lrpX:: GUS in hrp-inducing minimal medium (XOM2). The expression of lrpX was predicted to be self-regulated by its own translation product by directly binding to its own promoter. [ABSTRACT FROM AUTHOR]

The head is a major by-product (17.1% of body weight) of sturgeon aquaculture farming and remains unutilized. In this study, the sturgeon head was separated into the skull cartilage and mixed tissue: skin, scales, fins, muscles, bones, gills, and small cartilage pieces. Type A and B gelatins were extracted from the mixed tissue. The type B yield was higher, at 5.8% gelatin dry weight per tissue wet weight. The relative gelatin content in the sample weight, estimated from the sample's hydroxyproline content relative to that of the purified collagen, was higher in type A (60.3%) than in type B (39.7%). Type A gelatin showed higher intensities of the α- and β-bands of gelatin in SDS-PAGE, indicating that gelatin purity was higher in type A. The breaking force-strain curve showed a larger breaking force and lower breaking strain in type A (2.0 N, 12.1%), indicating that this gelatin is stronger than type B (0.7 N, 15.8%). Type B gelatin featured higher emulsion activity and stability and higher foam expansion and stability. In conclusion, type A and B gelatins with distinct proximate composition and functional properties were successfully extracted from sturgeon heads, which could act as a promising source of gelatins for industrial applications. • Sturgeon head shows high potential as a new source of fish gelatin. • Gelatin purity was determined by relative gelatin content and gelatin-band intensity. • Type A gelatin had higher purity and gel strength with higher gelling temperature. • Type B gelatin had higher emulsifying and forming activities. • Type A gelatin can be used in biomaterials or drugs and type B in foods or cosmetics. [ABSTRACT FROM AUTHOR]

Predictive maintenance, facilitated by smart devices and cyber infrastructure, is used for essential equipment like power transformers, enhancing power grid stability and reducing operating costs. As part of predictive maintenance, machine learning (ML) methods are employed to predict the remaining useful life (RUL) of power transformers, which can be vulnerable to cyber-attacks, especially data contamination attacks. Hence, this work introduces false data injection (FDI) attacks in ML-based RUL prediction and investigates the impacts on lifetime prediction. Three different attack templates of FDI attacks are implemented to corrupt the input data of extreme gradient boosting (XGBoost), extra trees (ETs) and random forest (RF)-based lifetime predictor models, where single attack templates are found severe compared to a mixed attack template of FDI attacks. Also, adversarial training is presented as a countermeasure, where the adversarially trained XGBoost model outperforms the other two models under normal conditions and cyber-attacks. Experiment results indicate that the lifetime prediction errors of the proposed model in all scenarios can be maintained at about 6 and 3 in terms of RMSE and MAE, respectively. • Introducing cyber-attacks on ML-based power transformer lifetime predictors. • Investigating the severity of single and mixed models of FDI attacks on predictors. • Presenting a comparative analysis of predictors under normal cases and cyber-attacks. • Proposing an adversarial training-based countermeasure to mitigate the severity. [ABSTRACT FROM AUTHOR]

Rice (Oryza sativa) stands as a crucial staple food worldwide, especially in Bangladesh, where it ranks as the third-largest producer. However, intensified cultivation has made high-yielding rice varieties susceptible to various biotic stresses, notably sheath blight caused by Rhizoctonia solani, which inflicts significant yield losses annually. Traditional fungicides, though effective, pose environmental and health risks. To address this, nanotechnology emerges as a promising avenue, leveraging the antimicrobial properties of nanoparticles like silver nanoparticles (AgNPs). This study explored the green synthesis of AgNPs using Ipomoea carnea leaf extract and silver nitrate (AgNO3), and also examined their efficacy against sheath blight disease in rice. The biosynthesized AgNPs were characterized through various analytical techniques such as UV-vis spectrophotometer, X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Particle size analyzer, Zeta potential, Scanning Electron Microscope (SEM), Field Emission Scanning Electron Microscope (FESEM), Transmission Electron Microscope (TEM) for confirming their successful production and crystalline nature of nanoparticles. The results of UV-visible spectrophotometers revealed an absorption peak ranging from 421 to 434 nm, validated the synthesis of AgNPs in the solution. XRD, DLS, and TEM estimated AgNPs sizes were ~45 nm, 66.2nm, and 46.38 to 73.81 nm, respectively. SEM and FESEM demonstrated that the synthesized AgNPs were spherical in shape. In vitro assays demonstrated the significant inhibitory effects of AgNPs on mycelial growth of Rhizoctonia solani, particularly at higher concentrations and pH levels. Further greenhouse and field experiments validated the antifungal efficacy of AgNPs against sheath blight disease in rice, exhibiting comparable effectiveness to commercial fungicides. The findings highlight the potential of AgNPs as a sustainable and effective alternative for managing rice sheath blight disease, offering a safer solution amidst environmental concerns associated with conventional fungicides. [ABSTRACT FROM AUTHOR]

This study examined the influence of soil physicochemical properties on the sorption, desorption and kinetics of beryllium (Be) uptake and release on soils from a legacy waste site in Australia. This information is needed to help explain the current distribution of Be at the site and evaluate potential future environmental risks. Sorption was determined by a batch study and key soil properties were assessed to explain Be retention. The soil was favourable for sorption of Be (up to 99%) due to organic content, negative surface charge, soil oxyhydroxides (Fe/Al/Mn–O/OH) and the porosity of the soil structure. Lesser sorption was observed in the presence of a background electrolyte (NaNO 3). Sorption closely followed pseudo second order kinetics and was best described by the Langmuir model. FTIR analysis suggested that chemisorption was the predominant mechanism of Be sorption. Desorption was very low and best described by the Freundlich model. The low desorption reflected the high K d (up to 6624 L/kg), and the presence of hysteresis suggested partially irreversible binding of Be with active surfaces of the soil matrix (minerals, SOM, oxyhydroxides of Fe/Al/Mn etc.). Intra-particle diffusion of Be and entrapment in the pores contribute to the irreversible binding. The sorption behaviour of Be helped to explain the relative immobility of Be at the site despite the significant quantities of Be disposed. Soil physicochemical properties were significant for Be sorption, through influencing both the uptake and desorption, and this demonstrates the implications of these measurements for evaluating potential future risks to the environment. Image 1 • Soil physico-chemistry is important for sorption-desorption chemistry of beryllium. • Very high sorption (up to 99%) which declined with background electrolyte. • High K d (up to 6624 L/kg) and hysteresis (<0.84) reflects low desorption at pH 5. • Organic matter, metal oxydroxides, clay and porosity were important for Be sorption. • Irreversible chemisorption was the predominant sorption process of soil to Be. [ABSTRACT FROM AUTHOR]

High penetration of Doubly Fed Induction Generator (DFIG) into existing power grid can attribute complex issues as they are very sensitive to the grid faults. In addition, Fault Ride Through (FRT) is one of the main requirements of the grid code for integrating Wind Farms (WFs) into the power grid. In this work, to enhance the FRT capability of the DFIG based WFs, a Bridge-Type Flux Coupling Non-Superconducting Fault Current Limiter (BFC-NSFCL) is proposed. The effectiveness of the proposed BFC-NSFCL is evaluated through performance comparison with that of the Bridge-Type Fault Current Limiter (BFCL) and Series Dynamic Braking Resistor (SDBR). Moreover, a dynamic nonlinear controller is also proposed for controlling the operation of the BFC-NSFCL. Extensive simulations are carried out in the MATLAB/SIMULINK environment for both symmetrical and unsymmetrical temporary as well as permanent faults. Based on the simulation results and different numerical analysis, it is found that the proposed nonlinear controller based BFC-NSFCL is very effective in enhancing the FRT capability of the WF. Also, the BFC-NSFCL outperforms the conventional BFCL and SDBR by maintaining a near-seamless performance during various grid fault situations. [ABSTRACT FROM AUTHOR]

Microgrids are designed to utilize renewable energy resources (RER) that are revolutionary choices in reducing the environmental effect while producing electricity. The RER intermittency poses technical and economic challenges for the microgrid systems that can be overcome by utilizing the full potential of hybrid energy storage systems (HESS). A microgrid comprising of a solar photovoltaic panel, wind turbine, lead-acid battery, electrolyzer, fuel cell, and hydrogen (H2\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$_{2}$$\end{document}) tank is considered for techno-economic feasibility and environmental impact assessment on a grid integration scenario. Mathematical functions are utilized to model the components for estimating annual hourly renewable generation and energy storage behavior. The load consumption model for 50 homes is generated using Gaussian distribution to incorporate the uncertainty. Optimal sizing of the microgrid components is determined using the particle swarm optimization (PSO) algorithm to minimize the upfront installation cost and levelized cost of energy (LCOE). Different energy storage penetration scenarios, e.g., 25%, 50%, 75%, and 100% for the microgrid system, are considered where 100% penetration level stands for maintaining the load demand using the available resources without depending on the grid energy supply. The lowest LCOE is found between 0.06 $/kWh and 0.11 $/kWh, and the highest annual GHG is reduced to half compared to the grid emission. GHG is imposed around 62.14 (tCO2\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$_2$$\end{document}e/yr) - 73.57 (tCO2\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$_2$$\end{document}e/yr) for Madrid and Seville, respectively. [ABSTRACT FROM AUTHOR]

The repair and regeneration of the injured tissues or organs is a major challenge for biomedicine, and the emerging 3D bioprinting technology as a class of promising techniques in biomedical research for the development of tissue engineering and regenerative medicine. Chitosan-based bioinks, as the natural biomaterials, are considered as ideal materials for 3D bioprinting to design and fabricate the various scaffold due to their unique dynamic reversibility and fantastic biological properties. Our review aims to provide an overview of chitosan-based bioinks for in vitro tissue repair and regeneration, starting from modification of chitosan that affect these bioprinting processes. In addition, we summarize the advances in chitosan-based bioinks used in the various 3D printing strategies. Moreover, the biomedical applications of chitosan-based bioinks are discussed, primarily centered on regenerative medicine and tissue modeling engineering. Finally, current challenges and future opportunities in this field are discussed. The combination of chitosan-based bioinks and 3D bioprinting will hold promise for developing novel biomedical scaffolds for tissue or organ repair and regeneration. [ABSTRACT FROM AUTHOR]

With technological developments, the resolution of the display systems is increasing, causing image data to increase. Several technologies are aiding in optimizing these data during transmission and storage while maintaining quality. Still, the internal data transmission for accessing the memory sub‐system during reading and writing cycles consumes significant power while requiring large memory for storage, which is inefficient, especially for portable displays. Hence, this work investigates the feasibility of reducing data through approximation for images in different formats and resolutions for human and computer vision based applications. Different image quality assessment metrics are utilized for performance evaluations with optimum image quality assessment selection according to application requirements. In addition, the feasibility analysis is conducted for three different applications as examples of computer vision. The experimental analysis highlights theoretical and industrial importance by showing that image data can be reduced from 25.0% to 62.5%, while satisfying requirements for HVS‐based and computer vision‐based applications. [ABSTRACT FROM AUTHOR]

NADPH oxidase (Nox) genes are responsible for Reactive Oxygen Species (ROS) production in living organisms such as plants, animals, and fungi, where ROS exert different functions. ROS are critical for sexual development and cellular differentiation in fungi. In previous publications, two genes encoding thioredoxin and NADH-ubiquinone oxidoreductase involved in maintaining ROS balance were shown to be remarkably induced in a highly versus a weakly aggressive Verticillium dahliae isolate. This suggested a role of these genes in the virulence of this pathogen. NoxA (NADPH oxidase A) was identified in the V. dahliae genome. We compared in vitro expression of NoxA in highly and weakly aggressive isolates of V. dahliae after elicitation with extracts from different potato tissues. NoxA expression was induced more in the weakly than highly aggressive isolate in response to leaf and stem extracts. After inoculation of potato detached leaves with these two V. dahliae isolates, NoxA was drastically up-regulated in the highly versus the weakly aggressive isolate. We generated single gene disruption mutants for NoxA genes. noxa mutants had significantly reduced virulence, indicating important roles in V. dahliae pathogenesis on the potato. This is consistent with a significant reduction of cellophane penetration ability of the mutants compared to the wild type. However, the cell wall integrity was not impaired in the noxa mutants when compared with the wild type. The resistance of noxa mutants to oxidative stress were also similar to the wild type. Complementation of noxa mutants with a full length NoxA clones restored penetration and pathogenic ability of the fungus. Our data showed that NoxA is essential for both penetration peg formation and virulence in V. dahliae. [ABSTRACT FROM AUTHOR]

Rice blast and bacterial blight diseases are the global threat for rice production. To develop blast and bacterial blight resistant lines, two blast resistance genes (Pi9 and Pb1) and three bacterial blight resistance genes (xa5, xa13 and Xa21) were pyramided in the background of premium quality rice variety BRRI dhan63 through marker-assisted backcross breeding. Pi9-US2, Pb1-US2 were used as donor parents for Pi9 and Pb1, respectively and for xa5, xa13 and Xa21, IRBB60 was used as a donor parent. Three crosses were made to pyramid these genes in BRRI dhan63. F1 to BC3F6 population was developed by continuous backcrossing, selfing and foreground selection. Segregation analysis (chi-square test) of genotypic and phenotypic data of 400 BC3F2 population revealed that the inheritance of blast and bacterial blight resistance followed the single gene Mendelian fashion. Finally, a total of 30 advanced lines were selected and out of them, 23 lines contained Xa4, xa5, Xa21, Pi9 and Pb1 genes, six lines contained Pi9, Xa4 and Xa21 genes and a single line contained Pi9, Xa4, xa5, xa13 and Xa21 genes. Disease score of 30 advanced lines ranged from 0 to 1 for both blast and bacterial blight disease whereas in susceptible BRRI dhan63 disease score ranged from 7 to 9. Among the advanced lines, BR(Path)13,811-BC3-13 had the highest yield (30.41 g) per hill followed by BR(Path)13,811-BC3-18 (29.37 g), BR(Path)13,811-BC3-40 (29.08 g) and BR(Path)13,811-BC3-29 (28.66 g). Markers of the present study could be employed in marker-assisted selection breeding and the pyramided lines of the present study could be released as resistant varieties or used as resistant donors in the breeding program to develop blast and bacterial blight resistant varieties. [ABSTRACT FROM AUTHOR]

In Bangladesh, the third largest producer of potatoes in Asia, late blight, caused by Phytophthora infestans, is the major constraint to production. Nevertheless, there is a lack of published information on the pathogen population. A collection of 69 isolates obtained from samples of infected potato foliage collected in 2018–2019 varied significantly in their aggressiveness to detached potato leaflets and tuber slices of cv. Diamant. On leaflets, most isolates were highly aggressive, colonizing more than half the surface in 7 days. On tuber slices, while some isolates were highly aggressive, those collected in 2019 were less so. There was a significant effect of the locations from which the isolates were obtained on aggressiveness to both leaflets and tuber slices, but aggressiveness to leaflets and to tuber slices was not significantly correlated. All isolates were A2 mating type and either intermediate (38%) or resistant (62%) in sensitivity to the fungicide metalaxyl. A subset of 24 isolates all had mitochondrial DNA haplotype Ia. Samples of P. infestans DNA (124) from infected potato foliage obtained from Bangladesh (2014–2019) were genotyped by 12-plex SSR. The vast majority (95%) were assigned to EU_13_A2, which was present in every year in which samples were collected. Numerous EU_13_A2 variants were identified, many specific to Bangladesh. Six samples (from 2017 to 2019) had genotypes distinct from EU_13_A2 and with no close match to known European lineages. It is concluded that the current P. infestans population of Bangladesh is dominated by the aggressive lineage EU_13_A2, also dominant in India and Pakistan. The implications of this for control of late blight are discussed. [ABSTRACT FROM AUTHOR]

Purpose: The novel study describes the behXavioural phenomena of family firm types and explores the relationship between the family firm types of control diversity and Research and Development (R&D) investments. Acquiring controlling rights is a psychological phenomenon for family firm owners. The moderating effect of CEO compensations on R&D investments is investigated. Methodology: We collected data of listed A-share family firms in China from 2011 to 2020 in the China Stock Market and Accounting Research database. We used Tobit regression for data analysis. Results/Finding: The study concludes that lone-controller family firms (LCFFs) are less willing to invest in R&D and multi-controller family firms (MCFFs) have positive behaviour towards R&D. The moderating role of CEO compensation deviates the willingness and behaviour to invest in R&D. Conclusion/Originality: To the best of our knowledge, this study is the first to outline the paradoxical empirical evidence on family firms and R&D investments by analysing control diversity and how the moderating role of CEO compensation nexus can alter willingness towards R&D. The study is a novel attempt following De Massis et al's framework to test the willingness and ability of LCFFs and MCFFs. Previous studies based on agency theory have tacitly assumed that ability and willingness exist in family-controlled firms. However, this study challenges this implicit assumption. [ABSTRACT FROM AUTHOR]

In Bangladesh, Fusarium proliferatum is a prevalent pathogen of maize plants that poses a significant threat to human health and livestock by producing carcinogenic fumonisin. However, the use of the Bacillus species, which can colonize the infected plant parts, has been practiced globally to mitigate fumonisin contamination in maize. In this study, B. subtilis MMM1, a native isolate from the maize rhizosphere, was found to be the most effective antagonist against F. proliferatum, which reduced their mycelial growth and total fumonisin accumulation by 85.31% and 85.12%, respectively, over control through a fivefold reduction in fungal population (1.1 × 104 CFU/g maize grain) in vitro. Furthermore, out of the five bacilli used in this study, B. subtilis MMM1 was able to increase the root and, shoot length, and the vigor index of maize seedlings, by colonizing the fresh roots at 82 × 106 CFU/g root tissue. This suggests that B. subtilis MMM1 might be put forth both as a biocontrol agent and a plant growth promoter in Bangladesh to combat F. proliferatum. Nevertheless, evaluation of its efficacy in reducing fumonisin contamination in maize should be investigated under field conditions. [ABSTRACT FROM AUTHOR]

Ralstonia solanacearum, a soil-borne and seed-borne plant pathogenic bacterium, causes bacterial wilt to several important crop plants causing substantial economic losses. To provide population information on this pathogen for developing effective control strategies, Rep-PCR was used to analyze the genetic variation of 18 representative isolates of R. solanacearum collected in Bangladesh. Phenotypic analyses revealed that all eighteen isolates belong to biotype 3 with wide diversity in aggressiveness on eggplant, tomato, and chili. Rep-PCR studies utilizing the REP, ERIC, and BOXIR primers showed a wide variation at the genetic level among the R. solanacearum isolates used in this study. Dendrogram constructed using REP, ERIC, and BOXIR primers based on banding patterns implied that R. solanacearum isolates were genetically diversified and distributed in four clusters at 83%, 80%, and 63% similarity index, respectively. The genetic relationship assayed by rep-PCR highlighted a wide range of genetic variation but no relation among geographical origin, aggressiveness, and phylogenetic groups of R. solanacearum isolates. These results conceded that other molecular markers related to virulence gene(s) might reveal the complex relationship among geographical origin, aggressiveness, and phylogenetic groups. [ABSTRACT FROM AUTHOR]

Lead (Pb) pollution in the environment predominantly occurs through anthropogenic activities, which pose significant threats to human health and that of biota. In this study, Pb and other elements were investigated in different soils (n = 52), crops (n = 24) and water (n = 13) around a lead-acid battery (LAB) recycling workshop in southwestern Bangladesh. Most of the elements' concentrations (except Se and Ag) in soil were lower than the background concentrations. However, excessive concentrations of Pb were found in both surface (966 ± 2414 mg kg−1 at 0–15 cm) and subsurface (230 ± 490 mg kg−1 at 15–30 cm) soil. Although no definitive pattern or direction in elemental concentration in soil was observed, relatively higher concentrations of most elements were detected at the southeast part of the factory. The LAB factory, brick kiln, agricultural and geogenic activities might be the sources of these elements in soil. Extremely high amounts of Cr, As, Cd, and Pb were found in the food crops around the area. In particular, the Pb concentrations were 114 ± 155 and 665 ± 588 mg kg −1 dry weight in rice grain and straw, respectively, which reflected the emissions of Pb from the LAB recycling workshop. Moreover, 40% and 100% of the groundwater samples exceeded, respectively, the WHO provisional guideline values for As (0.01 mg L−1) and Pb (0.05 mg L−1). Consequently, a high level of Pb contamination in the soil was observed while assessing different soil pollution indices. Human health risk assessment indicated severe carcinogenic (from Pb, As, and Cr intake) and non-carcinogenic (from Pb, As, Co, Cr, Ni and Sb intake) health risks are associated with rice and groundwater consumption. It is concluded that all LAB recycling workshops should be better managed to prevent Pb pollution from seeping into the environment. [Display omitted] • This study reports severe lead (Pb) pollution at the LAB factory, Magura, Bangladesh. •Pb acid battery recycling was responsible for elevated Pb emissions into the environment. •Rice grain and straw including other vegetables accumulated large amounts of Pb. •Lead in groundwater was17-fold higher than the WHO guideline value. [ABSTRACT FROM AUTHOR]

Injudicious application of available commercial herbicide formulations leads to water, air and soil contamination, which adversely affect the environment, ecosystems and living organisms. Controlled release formulation (CRFs) could be an effective way to reduce the problems associated with commercially available herbicides. Organo-montmorillonites are prominent carrier materials for synthesising CRFs of commercial herbicides. Quaternary amine and organosilane functionalised organo-montmorillonite and pristine montmorillonite were used to investigate their potential as suitable carriers for CRFs in herbicide delivery systems. The experiment involved a batch adsorption process with successive dilution method. Results revealed that pristine montmorillonite is not a suitable carrier for CRFs of 2,4-D due to its low adsorption capacity and hydrophilic nature. Conversely, octadecylamine (ODA) and ODA-aminopropyltriethoxysilane (APTES) functionalised montmorillonite has better adsorption capacities. Adsorption of 2,4-D onto both organoclays is higher at pH.3 (232.58% for MMT1 and 161.29% for MMT2) compared to higher pH until pH.7 (49.75% for MMT1 and 68.49% for MMT2). Integrated structural characterisation studies confirmed the presence of 2,4-D on the layered organoclays. The Freundlich adsorption isotherm model fitted best to the experimental data, which revealed an energetically heterogeneous surface of the experimental organoclays, and adsorption which specifically involved chemisorption. The cumulative desorption percentages of adsorbed 2,4-D from MMT1 (2,4-D loaded) and MMT2 (2,4-D loaded) after seven desorption cycles were 65.53% and 51.45%, respectively. This outcome indicates: firstly, both organoclays are potential carrier materials for CRFs of 2,4-D; secondly, they have the ability to reduce the instantaneous release of 2,4-D immediately after application; and thirdly, eco-toxicity is greatly diminished. [Display omitted] • Pristine montmorillonite (K10) is not a suitable carrier for CRFs of 2,4-D. • Energetically heterogeneous surface of both organoclays enhanced the chemisorption process. • Both organoclays have excellent desorption ability at a wide range of pH, temperatures, and ionic strengths. • ODA and APTES functionalised montmorillonites are potential carriers for CRFs of 2,4-D. • CRFs of 2,4-D using organo-montmorillonite may reduce eco-toxicity. [ABSTRACT FROM AUTHOR]

Bacterial wilt caused by Ralstonia solanacearum is a destructive disease of many economically important crop species. A significant variation in wilt incidence and severity in eggplant and potato was observed among the growing areas surveyed. R. solanacearum isolates obtained both from eggplant and potato belong to biovar III, while isolates from eggplant belong to race 1 and isolates obtained from potato belong to race 3. Random amplified polymorphic DNA (RAPD) technique was used as a tool for assessing genetic variation and relationship among seven isolate groups of R. solanacearum viz., RsB-1, RsB-2, RsB-3, RsP-1, RsP-2, RsP-3 and RsP-4, consisting in a total of 28 isolates. Out of the RAPD markers used, amplification with four decamer primers produced 70 bands with sizes ranging from 100 to 1400 bp. Out of 70 bands, 68 bands (97.06%) were polymorphic and two bands (2.94%) were monomorphic amongst the seven R. solanacearum isolates group. The Unweighted Pair Group Method of Arithmetic Means (UPGMA) dendrogram constructed from Nei's genetic distance produced two main clusters of the seven isolates of R. solanacearum . The isolates RsB-1, RsB-2, RsB-3 and R-4 grouped in cluster І, while RsP-2, RsP-3 and RsP-4 grouped in cluster ІІ. The highest intra-variety similarity index (S i ) was found in RsB-1 isolate (86.35%) and the lowest one in RsP-2 (56.59%). The results indicated that relatively higher and lower levels of genetic variation were found in RsP-3 and RsB-3, respectively. The coefficient of gene differentiation (G st ) was 0.5487, reflecting the existence of a high level of genetic variations among seven isolates of R. solanacearum . Comparatively higher genetic distance (0.4293) and lower genetic identity (0.6510) were observed between RsB-2 and RsP-4 combinations. The lowest genetic distance (0.0357) and highest genetic identity (0.9650) were found in RsB-1 vs. RsB-2 pair. Thus, RAPD offers a potentially simple, rapid and reliable method to evaluate genetic diversity analysis in R. solanacearum . [ABSTRACT FROM AUTHOR]

This study determines the bioaccessibility of toxic and carcinogenic arsenic (As) in composite food samples and evaluates potential exposure from food intake in Bangladesh children. Total As (tAs), inorganic As (iAs) and bioaccessible As (BAs) in food composite samples consumed by children were compared between an exposed and a control group (based on As in drinking water). Total As concentrations in composite food samples of children exposed to mean As level of 331 µg/l in drinking and cooking water ranged from 586 to 1975 µg/kg, dry weight over 76–90 µg/kg in the unexposed group. Average iAs in food composites was 73.9% (range: 49.3–90.8%). The fraction of BAs using gastric and gastrointestinal phases was 91 ± 13% and 98 ± 11%, respectively. Daily intake of iAs in the exposed group ranged from 0.41 to 6.38 µg per kg body weight (BW), which was much higher than the unexposed group (0.08–0.15 µg per kg BW). High iAs content and BAs in composite food samples indicated the elevated risk to exposed children. Further research should include both adults and children using larger sample size to determine overall As exposure from food intake in Bangladesh, attention must be given to lowering of As in food. ga1 • Arsenic bioaccessibility and speciation in food composites of children diet. • Inorganic arsenic in food composites was on average 74%. • Arsenic in food composites influenced by contaminated cooking water. • Arsenic bioaccessibility was higher in gastrointestinal (99%) than gastric phase (92%). • HQ and CR from food intake indicated high risk to children. [ABSTRACT FROM AUTHOR]

Citrus greening or Huanglongbing (HLB) is one of the most severe diseases of citrus worldwide and no cure is available at present. Currently molecular techniques based on polymerase chain reaction (PCR) are mainly used for the identification of HLB disease. The aim of this study was to identify the causal pathogen of citrus greening disease in Bangladesh. A total of eight mandarin orange leaf samples from three citrus growing areas viz. Moulvibazar, Sylhet and Khagrachari were collected on the basis of visual investigation demonstrating blotchy mottle symptoms. The genomic DNA was extracted from midribs of each leaf sample and subjected to the PCR. Species specific primers A2/J5 was used to amplify a partial sequence of β-operon (rpl KAJL- rpo BC operon) of ribosomal protein gene. An amplicon size of 703 bp specific to the Candidatus Liberibacter asiaticus confirmed its presence. BLAST homology search with the sequenced data showed 99% identity with the sequence database of Candidatus Liberibacter asiaticus deposited in GenBank. These results confirmed the prevalence of Candidatus Liberibacter asiaticus causing citrus greening in Bangladesh. • Citrus greening disease was identified. • Genomic DNA was extracted from midribs of each leaf sample. • A partial sequence of β-operon (rpl KAJL- rpo BC operon) of ribosomal protein gene was detected. • An amplicon size of 703 bp specific to the Candidatus Liberibacter asiaticus (Las) confirmed its presence. • BLAST homology search with the sequenced data showed 99% identity with sequences of the Las deposited in GenBank. [ABSTRACT FROM AUTHOR]