Chromatin is known to be organized into multiple domains of varying sizes and compaction. While these domains are often imagined as static structures, they are highly dynamic and show cell-to-cell ...variability. Since processes such as gene regulation and DNA replication occur in the context of these domains, it is important to understand their organization, fluctuation, and dynamics. To simulate chromatin domains, one requires knowledge of interaction strengths among chromatin segments. Here, we derive interaction-strength parameters from experimentally known contact maps and use them to predict chromatin organization and dynamics. Taking two domains on the human chromosome as examples, we investigate its three-dimensional organization, size/shape fluctuations, and dynamics of different segments within a domain, accounting for hydrodynamic effects. Considering different cell types, we quantify changes in interaction strengths and chromatin shape fluctuations in different epigenetic states. Perturbing the interaction strengths systematically, we further investigate how epigenetic-like changes can alter the spatio-temporal nature of the domains. Our results show that heterogeneous weak interactions are crucial in determining the organization of the domains. Computing effective stiffness and relaxation times, we investigate how perturbations in interactions affect the solid- and liquid-like nature of chromatin domains. Quantifying dynamics of chromatin segments within a domain, we show how the competition between polymer entropy and interaction energy influence the timescales of loop formation and maintenance of stable loops.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Accurate estimation of electrical parameters of voltage-source-inverter-fed induction machine (IM) drives is very important while employing high-dynamic-performance control schemes, such as vector ...control. Parameter estimation schemes reported in the literature can estimate only four parameters (<inline-formula><tex-math notation="LaTeX">R_s</tex-math></inline-formula>, <inline-formula><tex-math notation="LaTeX">L_{ss}</tex-math></inline-formula>, <inline-formula><tex-math notation="LaTeX">\sigma</tex-math></inline-formula>, and <inline-formula><tex-math notation="LaTeX">\tau _r</tex-math></inline-formula>) independently out of five electrical parameters (<inline-formula><tex-math notation="LaTeX">R_s</tex-math></inline-formula>, <inline-formula><tex-math notation="LaTeX">R_r</tex-math></inline-formula>, <inline-formula><tex-math notation="LaTeX">L_{\sigma s}</tex-math></inline-formula>, <inline-formula><tex-math notation="LaTeX">L_{\sigma r}</tex-math></inline-formula>, and <inline-formula><tex-math notation="LaTeX">L_m</tex-math></inline-formula>), when the core loss resistance is neglected. All the five parameters are not independently identified. This article proposes a parameter estimation method that independently identifies all the six electrical parameters (<inline-formula><tex-math notation="LaTeX">R_s</tex-math></inline-formula>, <inline-formula><tex-math notation="LaTeX">R_r</tex-math></inline-formula>, <inline-formula><tex-math notation="LaTeX">R_c</tex-math></inline-formula>, <inline-formula><tex-math notation="LaTeX">L_{\sigma s}</tex-math></inline-formula>, <inline-formula><tex-math notation="LaTeX">L_{\sigma r}</tex-math></inline-formula>, and <inline-formula><tex-math notation="LaTeX">L_m</tex-math></inline-formula>) of the IM, including the core loss resistance. Besides, the variation of core loss resistance with frequency is also discussed in this article. The Kalman filter algorithm is used to estimate machine parameters in the proposed method. In the proposed method, a sine-triangle pulsewidth modulation signal is used as input excitation, instead of pseudorandom binary sequence signals. The proposed estimation method is validated using both simulation and experimental results.
The objective of this article is to highlight the significance of net energy consideration in economic policymaking, which has received less or no attention from the stakeholders particularly in the ...context of developing economies like India. With the rapid growth in the renewable energy sector, in this period of the low-carbon energy transition, there appears to be a growth in gross energy output. However, the net energy outputs reaching the demand sector of the economy may still be low due to the large feedback energy requirements for such rapid growth in energy supply. Such reduced energy availability may lead to reduced gross domestic product (GDP) growth unlike what is envisaged by policymakers. This is in contrast to the conventional standpoint, where assumed economic growth scenarios are used for energy planning. Since electricity use and economic development are found to be strongly correlated for developing economies like India, it is expected that a reduction in net energy available from the power sector will impose constraints on the GDP growth. Hence, a very ambitious electricity supply programme such as the one based on solar electricity may be counterproductive to GDP growth.
•Sources and important examples of phenolic bioactives are discussed in the review.•Crucial role of the response surface methodology in extraction of phenolic bioactives is explained in the ...review.•Green methods for extraction of phenolics are well presented along with optimized values for achieving highest yields.•Mechanism of extraction of green methods are discussed in the review.
Phenolic compounds from plant sources have significant health-promoting properties and are known to be an integral part of folk and herbal medicines. Consumption of phenolics is known to alleviate the risk of various lifestyle diseases including cancer, cardiovascular, diabetes, and Alzheimer’s. In this context, numerous plant crops have been explored and characterized based on phenolic compounds for their use as supplements, nutraceutical, and pharmaceuticals. The present review highlights some important source of bioactive phenolic compounds and novel technologies for their efficient extraction. These techniques include the use of microwave, ultrasound, and supercritical methods. Besides, the review will also highlight the use of response surface methodology (RSM) as a statistical tool for optimizing the recoveries of the phenolic bioactives from plant-based matrices.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Easy and facile synthesis of AuNRs-g-C3N4 composite.•Synergsitically enhanced electrochemical properties of AuNRs-g-C3N4 composite.•Impedimetric sensing of NS1 in the linear range of 0.6 ng/mL to ...216 ng/mL with detection limit (0.09 ng/mL).•Sustainable and cost effective immunosensor of NS1 dengue biomarker.
Dengue has been a threatening vector-borne viral disease across different countries of the world. NS1 is a non-structural dengue biomarker that is released into the bloodstream during the initial stages of the infection and is used in the early diagnosis of the disease. In this work, we present a high-performance NS1 immunosensor based on gold nanorod decorated graphitic carbon nitride (AuNRs-g-C3N4) modified glassy carbon electrodes (GCE). AuNRs-g-C3N4 composite is synthesized, which possesses excellent electro-activity, fast electron transfer kinetics, and high catalytic property. NS1 antibody is immobilized onto the surface of the AuNRs-g-C3N4 modified GCE and used as an impedimetric sensing probe for the quantitative sensing of NS1 antigen through electrochemical impedance spectroscopy. We have chosen Fe (CN)63−/4− as a redox couple to observe the respective changes in charge transfer resistance (Rct) associated with antigen bonding with an antibody both in PBS buffer as well as in human serum. The prepared immunosensor shows an excellent electrocatalytic response for the quantitative determination of NS1. The analytical parameters obtained by using this immunosensor are found comparable or better to previously reported NS1 sensors and open new insights with great potential for the application of point of care besides application in the diagnosis of Dengue.
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This article proposes a multilevel dc-dc converter topology for fast charging of electric and plug-in hybrid electric vehicles (EVs and PHEVs). The proposed dc-dc converter topology converts the ...front end ac-dc converter output and provides regulated supply to the EV propulsion battery. The proposed topology consists of full-bridge converter at the primary, while the secondary side consists of voltage doubler rectifier units and combination of diodes and mosfet for reconfiguration of the voltage doubler rectifiers to generate the multilevel voltage. The multilevel voltage at the output helps in reducing the output filter size and increases the power density of the converter. The topology utilizes the resonance between leakage inductor of high frequency transformer, parasitic output capacitors of full-bridge mosfet s and voltage doubler capacitors to achieve soft switching (ZVS turn- on ) for all the full-bridge devices and soft turn- off for the rectifier diodes. The load limited ZVS turn on capability of conventional full-bridge topologies is mitigated through the use of resonance between magnetizing inductance of transformer and mosfet output capacitors. The converter is designed for 650 V dc bus input and 200-400 V EV battery output at 100 kW rated charging power. The analysis of the proposed converter in continuous and discontinuous modes of operation, soft switching operation, and the component design guidelines are presented in this article. The proposed converter is validated through detailed PLECS simulation results for 100 kW charging power. Experimental results from laboratory prototype of 500 W power are also presented to validate the design methodology and converter performance.
Corrosion is an ever-present phenomena of material deterioration that affects all metal structures. Timely and accurate detection of corrosion is required for structural maintenance and effective ...management of structural components during their life cycle. The usage of aircraft materials has been primarily driven by the need for lighter, stronger, and more robust metal alloys, rather than mitigation of corrosion. As such, the overall cost of corrosion management and aircraft downtime remains high. To illustrate, $5.67 billion or 23.6% of total sustainment costs was spent on aircraft corrosion management, as well as 14.1% of total NAD for the US Air Force aviation and missiles in the fiscal year of 2018. The ability to detect and monitor corrosion will allow for a more efficient and cost-effective corrosion management strategy, and will therefore, minimize maintenance costs and downtime, and to avoid unexpected failure associated with corrosion. Conventional and commercial efforts in corrosion detection on aircrafts have focused on visual and other field detection approaches which are time- and usage-based rather than condition-based; they are also less effective in cases where the corroded area is inaccessible (e.g., fuel tank) or hidden (rivets). The ability to target and detect specific corrosion by-products associated with the metals/metal alloys (chloride ions, fluoride ions, iron oxides, aluminum chlorides etc.), corrosion environment (pH, wetness, temperature), along with conventional approaches for physical detection of corrosion can provide early corrosion detection as well as enhanced reliability of corrosion detection. The paper summarizes the state-of-art of corrosion sensing and measurement technologies for schedule-based inspection or continuous monitoring of physical, environmental and chemical presence associated with corrosion. The challenges are reviewed with regards to current gaps of corrosion detection and the complex task of corrosion management of an aircraft, with a focused overview of the corrosion factors and corrosion forms that are pertinent to the aviation industry. A comprehensive overview of thin film sensing techniques for corrosion detection and monitoring on aircrafts are being conducted. Particular attention is paid to innovative new materials, especially graphene-derived thin film sensors which rely on their ability to be configured as a conductor, semiconductor, or a functionally sensitive layer that responds to corrosion factors. Several thin film sensors have been detailed in this review as highly suited candidates for detecting corrosion through direct sensing of corrosion by-products in conjunction with the aforementioned physical and environmental corrosion parameters. The ability to print/pattern these thin film materials directly onto specific aircraft components, or deposit them onto rigid and flexible sensor surfaces and interfaces (fibre optics, microelectrode structures) makes them highly suited for corrosion monitoring applications.
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The two most commonly used induction motor control methods are the scalar (<inline-formula><tex-math notation="LaTeX">V/f</tex-math></inline-formula>) and vector (field-oriented) control techniques. ...<inline-formula><tex-math notation="LaTeX">V/f</tex-math></inline-formula> control has good steady-state response and robustness against the variation in machine parameters, but the resulting torque dynamics are poorer. Vector control achieves better dynamic performance by decoupling the flux- and torque-producing components of the stator current. Vector-controlled techniques are heavily dependent on the machine parameters and are sensitive to the variation in machine parameters. This paper proposes a novel control technique, which integrates the robustness features of scalar control and good dynamic performance of vector control. Estimation of the transient vector is responsible for improving dynamics in the proposed control. The proposed control technique uses an optimal controller with an output feedback law. The operation of the proposed control is validated experimentally under both steady-state and transient conditions. Finally, the proposed control is compared with both the <inline-formula><tex-math notation="LaTeX">V/f</tex-math></inline-formula> and vector control strategies in terms of dynamic performance and parameter sensitivity.
High voltage direct current (HVdc) power transmission systems do not encounter any natural zero crossing unlike the ac systems, and hence, the dc circuit breakers employed should be fast-acting and ...reliable to ensure safe operation. Circuit breakers (CBs) that have fast response time with lower energy loss dissipation are required for subsea HVdc transmission systems. This article investigates the performance of various CB topologies, including ultrafast coupled inductor hybrid CB (CIHCB) topology without and with the integration of resistive-type superconducting fault current limiter (R-SFCL) for a 100-kV, 100-MW HVdc transmission systems. It is found that the addition of R-SFCL with 1.7-ms response time decreases the peak current through the breaker and, hence, the power dissipated in the CB during short-circuit fault conditions. Thus, the rating of CB can be significantly decreased with the proposed topology. Furthermore, a comparison of power loss in CIHCB with the existing topologies, such as mechanical CB, resonant CB, and HVdc-hybrid CB, are also presented in this article.
Here, we demonstrates the fabrication of binder free and very efficient supercapacitor electrode based on tungsten nitride (W2N) thin film on stainless steel (SS) substrate using reactive sputtering ...technique. W2N thin film as a working electrode exhibits high specific capacitance (163 F g−1 at 0.5 mA cm−2 in 1 M H2SO4) along with excellent cycling stability. The binder free symmetric supercapacitor (W2N||W2N) device delivers a high specific capacitance (80 Fg-1) and long life span (90.46% capacitance retention after 10,000 cycles) along with high energy (12.92 Whkg−1) and power (∼674 kWkg−1 at 9.36 Whkg−1) densities. These observed excellent electrochemical performances of the present W2N thin film based supercapacitor device, recommend it as a potential candidate for energy storage applications.
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•W2N thin film is deposited on stainless steel substrate using reactive sputtering.•A binder free symmetric device based on W2N/SS configuration is constructed.•W2N||W2N device exhibits high energy density and outstanding cycling stability.•The W2N||W2N supercapacitor device shows a long retention for 10,000 cycles.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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