Search

The Poincaré plot based non-linear heart rate variability (NLHRV) parameters are helpful to understand the heart rate asymmetry (HRA). These are also identified as HRA descriptors. The HRA represents a physiological phenomenon that signifies the persistent difference in how heart rate decelerations and heart rate accelerations affect the functioning of the human cardiovascular system. Most of the HRA descriptors are variance-based descriptors. These HRA descriptors can be evaluated using the time-series signal consisting of inter-beat intervals (IBI). Rather than deriving the IBI signal using high-resolution R-peak detection for an electrocardiogram (ECG) signal, compressed sensing (CS) based R-peak detection for IBI signal computation is more suitable especially when short-term fast cardiac heath monitoring is our prime concern. For this comparative study, 48 ECG signal records of MIT-BIH arrhythmia (MIT-BIH-A) database and 18 ECG signal records of MIT-BIH normal sinus rhythm (MIT-BIH-NSR) database are used. A set of 23 HRA descriptors has been evaluated using both R-peak detection methods for 1 min duration signal from above mentioned databases. For comparative HRA analysis, we have observed more than 95% similar values for all 23 HRA descriptors for both databases. Comparative error analysis is presented in this paper to validate the suitability of the compressed ECG sensing based NLHRV analysis with respect to the conventional high resolution ECG based non-linear HRV analysis. Role of short-term fast ECG sensing using wearable IoT devices is significant and short-term NLHRV analysis is helpful for the fast health monitoring. • Compressed ECG sensing based heart rate asymmetry (HRA) analysis is proposed. • Performance comparison of Poincare plot based HRA descriptors is presented. • More than 95% similar values for all 23 HRA descriptors are obtained on comparison with conventional methods. • This ultra short-term ECG signal based HRA analysis is suitable for fast health monitoring. [ABSTRACT FROM AUTHOR]

The increased interest over multi-lobed hybrid airships which have been recently identified as an ideal platform for high altitude long endurance applications urges to develop a methodology for conceptual design optimization. The sizing methodology estimates the area of solar array required to meet the constraints of energy balance and the weight/lift equilibrium. The methodology involves the coupling of four disciplines (viz., Environment, Geometry, Aerodynamics, and Energy) and accounts for their mutual interactions. Sizing of the airship is carried out in terms of five design variables corresponding to the geometry and layout of the envelope and the solar array. This methodology is coupled to an intelligence-based heuristic algorithm viz., Particle Swarm Optimization (PSO) to obtain the configuration corresponding to a minimum area of solar array for such an airship, meeting the user-specified operating requirements. The effect of wind speed, airship attitude and altitude, geographical location and day of operation on the optimum area are included in this study. The results show the effect of season and operating conditions of deployment on the optimal envelope shapes obtained for deployment on specific days of the year. This study helps in the preliminary design of solar array on an unconventional stratospheric airship. [ABSTRACT FROM AUTHOR]

Abstract The electronic structure, magnetic and mechanical properties of XMgC (X = Li, Na, K, Rb) in half – Heusler (C1 b) type structure are computed for various phases such as α, β and γ phases using first principles calculation based on density functional theory with generalised gradient approximation as the exchange correlation function and HSE06 hybrid function. The β phase is found to be the most stable one for these carbides at normal pressure. A structural phase transition from β to α phase in NaMgC and β to γ phase in RbMgC is predicted at the pressures of 19 GPa and 14 GPa respectively. The electronic structure calculation with HSE06 hybrid function predicts that LiMgC, NaMgC, KMgC and RbMgC are half metallic materials with energy gap of 1.855 eV for LiMgC in spin down stare and 2.172 eV, 2.101 eV, 1.739 eV in the spin up state for NaMgC, KMgC and RbMgC respectively. The calculated elastic constants satisfy the stability criteria and hence these carbides are mechanically stable in their most stable phase. The bulk modulus, shear modulus, Young's modulus and Poisson's ratio are also calculated. Highlights • Structural stability of XMgC (X = Li,Na,K,Rb) is analysed. • These carbides exhibit half-metallic ferromagnetism. • Structural phase transition is observed at high pressure. • Ferromagnetic to non-magnetic phase transition is observed. • Phonon dispersion curve predicts that LiMgC and NaMgC are dynamically stable. [ABSTRACT FROM AUTHOR]

Abstract The search for hard refractory materials has recently been attractive in the field of material science. The structural stability, electronic structure, and mechanical properties of noble metal carbides M 2 C and MC 2 (M = Os, Ir, Pt) are investigated in tetragonal (P 4/ mbm), fluorite/antifluorite (Fm3m), orthorhombic (Pnnm), pyrite (Pa-3) and hexagonal (P 6/ mmm) phases for their potential ability and use as hard materials, by the first principles calculation based on density functional theory. It is found that M 2 C are most stable in anti -fluorite structure, while MC 2 are stable in hexagonal structure. In Os 2 C and Pt 2 C, structural phase transition is predicted from antifluorite to pyrite whereas antifluorite to hexagonal in Ir 2 C and hexagonal to tetragonal in OsC 2 and PtC 2 under high pressure. Born-Huang criteria for mechanical stability are satisfied by the elastic constants of M 2 C and MC 2. The bulk modulus of these materials is found to be high, which indicates that these materials are super hard materials. Highlights • Metal carbides M 2 C are stable in anti -fluorite structure. • Metal carbides MC 2 are stable in hexagonal structure. • Structural phase transition is observed at high pressure. • Electronic structure indicates that these carbides are metallic. • Mechanical properties indicate that these metal carbides are superhard materials. [ABSTRACT FROM AUTHOR]

This paper proposes the performance of a Photo Voltaic (PV) system with SEPIC Converter where the switching is controlled by Maximum Power Point Tracking (MPPT) technique connected switched diode Multi Level Inverter (MLI) topology. MLI are suitable in high voltage & high power application due to their ability to synthesize waveforms with better harmonic spectrum. This paper presents (A) the design and study of PV and (B) V-I characteristics of PV system. Then, the output is connected to SEPIC converter and the switching is done by Perturb and Observe (P&O) type MPPT algorithm. Finally, Sinusoidal Pulse Width Modulation (SPWM) based switched diode Multilevel Inverter is connected to this above mentioned system. This switched diode multilevel inverter strategy enhances the fundamental output voltage and reduced total harmonic distortion. The proposed asymmetrical switched diode multilevel inverter is simulated using MATLAB/Simulink and the corresponding results are presented in this paper. [ABSTRACT FROM AUTHOR]

Alloy 686 is a highly corrosion resistant 21st-Century Nickel based superalloy derived from Ni-Cr-Mo ternary system. The alloying elements chromium (Cr) and molybdenum (Mo) are added to improve the resistance to corrosion in the broad range of service environment. The presence of a higher percentage of alloying elements Cr and Mo lead to microsegregation and end up with hot cracking in the fusion zone of Nickel-based superalloys. However, there is scanty of information regarding the welding of alloy 686 with respect to the microsegregation of alloying elements. The present study investigates the possibility of bringing down the microsegregation to cut down the formation of secondary phases in the fusion zone. The weld joints were fabricated by Gas Tungsten Arc Welding (GTAW) and Pulsed current gas tungsten arc welding (PCGTAW) with ERNiCrMo-10 filler and without filler wire (autogenous) mode. The microstructural properties of the weld joints were studied with optical and Scanning Electron Microscope (SEM). The joints fabricated by pulsed current (PC) technique shows refined microstructure, narrower weld bead and practically no heat affected zone (HAZ). Scanning Electron Microscope demonstrates the presence of secondary phases in the interdendritic regions of GTAW case. Energy Dispersive X-ray Spectroscopy (EDS) analysis was carried out to evaluate the microsegregation of alloying element. The results show that the segregation of Mo noticed in the interdendritic zone of GTAW both autogenous and filler wire. Tensile and Impact tests were done to evaluate the strength, ductility, and toughness of the weld joints. The results show that the PCGTA helps to obtain improved strength, ductility and toughness of the weld joints compared to their respective GTAW. Bend test did not lead to cracking irrespective of the type of welding adopted in the present study. [ABSTRACT FROM AUTHOR]

The following study demonstrates the effective sensing ability of nano-platform mediated microwave digestion in single cancer cells and cancer stem cells analysis using MALDI-MS. We synthesized gold nanoparticles (10–17 nm) and ornamented them with biomolecules from FBS (80–120 nm), for effective internalization and surface enrichment of gold nanoparticles on the cancer cells. The biological mimicking of the NP surface with biomolecules, led to its successful interaction with the cancer cells. These particles showed excellent biocompatibility. A combination of the nanoparticle mediated microwave digestion in enhancing the detection sensitivity of MALDI-MS was demonstrated on 1000, 100, 10 and finally 1 cancer cell concentration. Microwave digestion in the presence of nanoparticles enhanced the sensing ability upto 60% of MALDI-MS signals, leading to detection of molecules from a single cancer cell. The results suggest the future use of this method for the sensitive detection of single cancer cells in clinical analytes too. With this bio-mimicked nanoplatform based sensing technique, we have succeeded in obtaining MALDI MS signals from single cells of human breast origin (breast normal, cancer and cancer stem cells). [ABSTRACT FROM AUTHOR]

The problem of synchronization for fuzzy bidirectional associative memory (BAM) neural networks (NNs) with various time delays is formulated and investigated. The various delays consist of discrete delays, unbounded distributed delays and constant delay in the leakage term (i.e. ‘leakage delay’) are considered. Then, some sufficient conditions are presented to guarantee the global asymptotic stability of the error dynamical system by using Lyapunov–Krasovskii functional and linear matrix inequality (LMI) method. As a result, we achieved synchronization of master-slave (drive-response) fuzzy BAM NNs systems. Even, if there is no leakage delay, the obtained results are less restrictive to some known sufficient conditions. Moreover, the proposed results do not require the boundedness, differentiability and monotonicity of the activation functions, which can also be easily checked via the LMI solver in robust control toolbox in Matlab. Furthermore, using a parameter-dependent Lyapunov function approach the synchronization problem for polytopic uncertain fuzzy BAM NNs with various time delays is considered. The parameter uncertainties under consideration are assumed to belong to a fixed convex polytope. Finally, two numerical examples and simulations are given to illustrate the effectiveness of the derived theoretical results. [ABSTRACT FROM AUTHOR]

BaMg 1− x Mn x F 4 (0≤ x ≤0.07) samples were prepared by hydrothermal method which have heterogeneous particle size distribution with combined hexagonal and rectangular shapes. An isovalent Mn ion at Mg site induces antiferromagnetism at room temperature and the antiferromagnetic nature is confirmed by Arrott–Belov–Kouvel plot. Magnetization values taken at 15 kOe initially increases and then decreases with increase in the Mn concentrations. Undoped and doped samples show unsaturated ferroelectric loops with lossy nature and the lossy nature is found to decrease with increase in doping concentration. BaMg 0.95 Mn 0.05 F 4 exhibits a stable resistivity behavior over the temperature range 350–650 K. Almost a flat response in dielectric properties is observed for all the samples at 100 kHz in the measured temperature range. The probable origin of magneto-dielectric effect is discussed based on the study at a frequency of 1 kHz at room temperature. [ABSTRACT FROM AUTHOR]

LiNbO 3 , prepared by ball milling assisted ceramic method, exhibits weak ferromagnetism and ferroelectricity at room temperature. X-ray diffraction pattern reveals the rhombohedral phase of LiNbO 3 with hexagonal unit cell symmetry. The weak ferromagnetic behavior, obtained using VSM, has been explained using Dzyaloshinskii–Moriya interaction caused by the ferroelectric distortion in its magnetic order. The P – E loop measurement shows lossy natured ferroelectric loop. Electrical and dielectric properties analyzed using impedance spectroscopy show two thermally activated conduction processes, derived from the Arrhenius plot. A gradual increase in the dielectric constant below 493 K and a rapid increase above 493 K reveals the contribution of polarization components and Lithium ion hopping. [ABSTRACT FROM AUTHOR]

This Experimental research article presents a bead on plate welding of AISI 316L welded with continuous Laser Beam Welding (LBW). An attempt is made to find a process parameter for a full penetration weld bead profile; with less segregation effect. The experiments were carried out in two sets on an AISI 316L austenitic stainless steel plate (200 × 150 × 5 mm). In the first set, trial welds were carried out by keeping the laser speed at 400 mm/min and in the second set; it was kept at 800 mm/min. In both the cases, the laser power was varied from 1000 W, 1500 W and 2000 W. Metallurgical and mechanical characterizations were carried to evaluate the weld beads. Macro and micro structural analysis is carried done to evaluate the bead profile and microstructures. Ferrite content in terms of ferrite number (FN) in the weld zone is evaluated using Fischer Feritscope. Scanning Electron Microscope (SEM)\Energy Dispersive X-ray Spectroscopy (EDS) was used to characterize the weld beads for segregation effect. Vickers micro hardness test was carried out across the cross section of the weld beads to find the hardness distribution. Better result was obtained for the trial bead with parameter 800 mm/min and 2000W. [ABSTRACT FROM AUTHOR]

In the present work, a Design Of Experiment (DOE) technique, the Taguchi method was employed to bead on welding trials to optimize Pulsed Current Gas Tungsten Arc (PCGTA) welding process parameters of alloy C-276. A L9 orthogonal array of Taguchi design involving nine experiments for four parameters (pulsed current, background current, % on time, pulse frequency) with three levels was used. An analysis of the mean of signal-to-noise (S/N) ratio indicates that the depth of current is influenced significantly by the levels in the Taguchi orthogonal array. The higher the better response category was selected to obtain optimum conditions for depth of penetration. The optimum conditions were found to be 165 A pulse current, 77 A background current, 60% on time and 5 Hz pulse frequency. Analysis of Variance (ANOVA) is performed to measure percentage contribution of each factor. The results show that the pulse current was most influencing parameter on the depth of penetration and % on time (23.28%) the next most influencing. Confirmation test was carried out to validate the results of Taguchi analysis; the result shows that there is good match between expected and predicted results. [ABSTRACT FROM AUTHOR]

Cardiovascular disease (CVD) is one of the most widespread health problems with unpredictable and life-threatening consequences. The electrocardiogram (ECG) is commonly recorded for computer-aided CVD diagnosis, human emotion recognition and person authentication systems. For effective detection and diagnosis of cardiac diseases, the ECG signals are continuously recorded, processed, stored, and transmitted via wire/wireless communication networks. But long-term continuous cardiac monitoring system generates huge volume of ECG data daily. Therefore, a reliable and efficient ECG signal compression method is highly demanded to meet the real-time constraints including limited channel capacity, memory and battery-power of remote cardiac monitoring, ECG record management and telecardiology systems. In such scenarios, the main objective of the ECG signal compression is to reduce the data rate for effective transmission and/or storage purposes without significantly distorting the clinical features of different kinds of PQRST morphologies contained in the recorded ECG signal. Numerous ECG compression methods have been proposed by exploiting the intra-beat correlation, inter-beat correlation and intra-channel correlation of the ECG signals. This paper presents a prospective review of wavelet-based ECG compression methods and their performances based upon findings obtained from various experiments conducted using both clean and noisy ECG signals. This paper briefly describes different kinds of compression techniques used in the one-dimensional wavelet-based ECG compression methods. Then, the performance of each of the wavelet-based compression methods is tested and validated using the standard MIT-BIH arrhythmia databases and performance metrics. The pros and cons of different wavelet-based compression methods are demonstrated based upon the experimental results. Finally, various practical issues involved in the validation procedures, reconstructed signal quality assessment, and performance comparisons are highlighted by considering the future research studies based on the recent powerful digital signal processing techniques and computing platform. [ABSTRACT FROM AUTHOR]

The main objective of this research work is to investigate the feasibility of Friction Stir Welding (FSW) of AA7075 T6 and AA2024 T3 dissimilar aluminum alloys, with thickness ratio of 1.3, and to investigate the mechanical and structural properties of the weld. Since both AA2024 T3 and AA7075 T6 are not weldable by fusion welding processes, FSW process is used to weld both of these dissimilar alloys. Defect-free, tailor weld blanks were produced on the plates of AA7075 T6 and AA 2024 T3 having thickness of 6.5 mm and 5 mm respectively. The process parameters employed in this study include the tool rotation and travel speeds. The FSW tool employed in this study was made using AISI H13 tempered steel with square pin profile having pin diameter of 5 mm, concavity at pin start of 1 mm and pin length of 4.85 mm. The welded plates have been characterized for their mechanical and metallurgical properties. The effects of tool rotational speed and the welding speed on the joint performance were discussed. [ABSTRACT FROM AUTHOR]

Bimetallic combinations of Monel 400 and Hastelloy C276 are widely used in the high temperature applications. This paper investigates the weldability of these metals by Gas Tungsten Arc Welding technique employing ERNiCrMo-3 filler wire. Studies were carried out to characterize the weldments for its mechanical and metallurgical properties. Tensile tests confirmed that the strength of the weld zone is higher as compared to the parent metals. Structure-property relationships have been studied using the combined techniques of optical microscopy and SEM/EDAX analysis. [ABSTRACT FROM AUTHOR]

This research work presents mechanical and metallurgical investigations on commercially pure copper and austenitic stainless steel AISI 304 dissimilar joints produced by shielded metal arc welding. The effect of three different electrodes: Inconel (ENiCrMo3), Monel (ENiCu7) and stainless Steel (E316L) on this bimetallic combination were evaluated. Mechanical and metallurgical investigations were carried out on the welded joints. Various microstructures like equiaxed, columnar, cellular dendritic and delta ferrites were observed in the various zones of the weldments. Vickers microhardness plots showed that the CP-copper HAZ had the least hardness. Minimum strength requirement was met by joints produced by all the electrodes. Due to grain coarsening effect in the heat affected zone of CP copper all the weldments fractured in this region. SEM tensile fractographs revealed ductile modes of fracture in all weldments. Joint with ENiCrMo3 electrode showed the maximum strength and that with ENiCu7 electrode showed the least strength. [ABSTRACT FROM AUTHOR]

The present work investigates the microstructure and mechanical properties of the alloy C-276 by using continuous neodymium: yttrium aluminum garnet (Nd: YAG) laser welding process. Weldingtrials were carried out by varying the scan speed of the laser beam from 550 mm/min to 1200 mm/min. The scan speed of 550 mm/min was found to give good weld quality with no lack of penetration, and was adopted for the work reported here. The laser power was kept constant at 2 KW. Optical microscope and Scanning Electron Microscope (SEM) were used to study the microstructural features of the weld joint. Energy Dispersive X-ray Spectrometry (EDS) analysis was carried out to study the extent of segregation in the weld joint. Tensile tests were carried out to determine the strength and ductility of weldment. The microstructure in the fusion zone is predominated by fine cellular structure. The higher hardness in the weld zone is believed to be resulting from the fine dendritic structure compared to the relatively coarse grain structure of base metal. Microsegregation in fusion zone was found to be within acceptable limits, but there was evidence for macrosegregation. The weld joints exhibited tensile strength matching well with that of base metal (760 MPa) with good ductility (40%). [ABSTRACT FROM AUTHOR]

Abstract: This study demonstrates the effective synthesis of five different sized/shaped Pt NPs, within a narrow size regime of 1–21 nm using a modified methodology and the toxicity/biocompatibility of Pt NPs on Neuro 2A cancer cells was investigated elaborately by using light microscopic observations, tryphan blue exclusion assay, MTT assay and ICP-MS. The Pt NPs-C with sizes 5–6 nm showed superior non-cytotoxic property compared to the other four Pt NPs. These non-cytotoxic Pt NPs were employed for successful photothermal treatment of Neuro 2A cell lines using near-IR 1064 nm of laser irradiation. The Pt NPs-C could generate a 9 °C increase in temperature leading to effective photothermal killing of cancer cells. The MALDI-MS was used to prove the possibility of apoptosis related triggering of cell death in the presence of the Pt NPs. The results confirm that the current approach is an effective platform for in vivo treatment of neuro cancer cells. [Copyright &y& Elsevier]

• Proposed multidisciplinary design optimization approach for hybrid airship. • Developed Kriging-based surrogate model to evaluate envelope drag coefficient. • Particle Swarm Optimization technique hybridized with Pattern Search method. • Sensitivity analysis of energy storage devices. In the recent years, there has been a lot of interest in developing hybrid airships as aerial platforms for various applications because of their several advantageous features. This paper presents a multi-disciplinary design optimization based methodology for an airship with a tri-lobed envelope. The proposed methodology involves five disciplines, viz., Geometry, Environment, Energy, Aerodynamics and Structures. To reduce computational complexity involved in evaluating the aerodynamic characteristics of the tri-lobed envelope, a Kriging-based surrogate model was developed to estimate the envelope drag coefficient and coupled to the optimization framework to achieve the optimal solutions for different operating conditions. The surrogate model predicts the drag coefficient of the tri-lobed envelope with less than ± 3% error with respect to the results obtained through CFD. Since the problem follows a multi-disciplinary design approach, a composite objective function is formulated based on volume of the envelope, area of the solar array, and total mass of the airship, which isminimized using Particle Swarm Optimization (PSO) Algorithm. This study reveals that for meeting the same mission requirements, a tri-lobed airship powered by regenerative fuel cells requires half the volume and 33.5% lower solar array area, and has ~ 46% lower mass compared to the one powered by rechargeable batteries. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a novel Wavelet Energy based diagnostic distortion (WEDD) measure is proposed to assess the reconstructed signal quality for ECG compression algorithms. WEDD is evaluated from the Wavelet coefficients of the original and the reconstructed ECG signals. For each ECG segment, a Wavelet energy weight vector is computed via five-level biorthogonal discrete Wavelet transform (DWT). WEDD is defined as the sum of Wavelet energy weighted percentage root mean square difference of each subband. The effectiveness of this measure is validated by linear (linear polynomial and cubic polynomial) and nonlinear (logistic) regression analysis between the computed WEDD values and the mean opinion score (MOS) given by cardiologists. WEDD provides a better prediction accuracy and exhibits a statistically better monotonic relationship with the MOS ratings than Wavelet based weighted percentage root mean square difference (PRD) measure (WWPRD), PRD and other objective measures. Standard correlation coefficient and Spearman rank-order correlation coefficient (SROCC) between the WEDD/MOS ratings is 0.969 and 0.9624, respectively. [Copyright &y& Elsevier]

Abstract: In this paper, a new Wavelet threshold based ECG signal compression technique using uniform scalar zero zone quantizer (USZZQ) and Huffman coding on differencing significance map (DSM) is proposed. Wavelet coefficients are selected based on the energy packing efficiency of each sub-band. Significant Wavelet coefficients are quantized with uniform scalar zero zone quantizer. Significance map is created to store the indices of the significant coefficients. This map is encoded efficiently with less number of bits by applying Huffman coding on the differences between indices in the significance map. ECG records from the MIT-BIH arrhythmia database are selected as test data. For the record 117, the proposed technique achieves a compression ratio of 18.7:1 with lower percentage root mean square difference (PRD) compared to other threshold based methods. The proposed technique is tested for MIT-BIH arrhythmia record 119 and a compression ratio of 21.81:1 is achieved with a PRD value of 3.716% which is much lower compared to the reported PRD value of 5.0 and 5.5% of set partitioning in hierarchical tress (SPIHT) and analysis by synthesis ECG compressor (ASEC), respectively. The noise eliminating capability of the proposed technique is also demonstrated in this work. The proposed technique achieves the required compression ratio with less reconstruction error for GSM-based cellular telemedicine system. [Copyright &y& Elsevier]

GdMnO 3 (GMO) thin films were deposited on (100) oriented SrTiO 3 (STO) and Quartz substrates, by RF Magnetron Sputtering. A film thickness of 320–330 nm was optimized to understand the intriguing role of both substrates on the structural, topographical and magnetic properties of GMO. Orthorhombic phase of GMO is confirmed on both the STO and Quartz substrates. Uniform plane growth is observed in the (100) direction of STO, whereas a polycrystalline feature with an island growth is observed on the Quartz substrate. GMO deposited on both the substrates shows canted antiferromagnetism at ∼25 K and a paramagnetic-antiferromagnetic transition at T N ∼47 K. But a cusp representing spin glass transition is observed in GMO coated on Quartz substrate at low temperature ZFC measurements. • GdMnO 3 films were deposited successfully on SrTiO 3 and Quartz substrates via RF magnetron sputtering. • Structural studies confirm the polycrystalline growth of deposited GdMnO 3 on Quartz and the topographic images show smooth surfaces with small island like grains for both the film. • GdMnO 3 thin film shows antiferromagnetism at ∼25 K and paramagnetic-antiferromagnetic transition at TN ∼47 K for both the film. • The SQUID – VSM study on GdMnO 3 /Quartz films reveals a cusp representing the spin glass transition, which is absent in the case of GdMnO 3 /SrTiO 3. [ABSTRACT FROM AUTHOR]

Future electronic gadgets will often require computer – human interaction, necessitating the use of conformal and flexible electronic devices. Because of its low cost, biocompatibility, high flexibility and lower temperature manufacturing, OTFTs have sparked a lot of research. OTFT arrays with high performance and good integrating density have been regarded as essential enablers for subtle displays, flexible circuits & sensors and electronic skins. OTFTs offered a mobility and I ON /I OFF of 10–43 cm2/Vs and 106–1010 respectively. This article highlights the various architectures, emerging p/n-type organic semiconductor channel materials, substrate/dielectrics/electrode materials used for developing high performance OTFTs. This article also point out the emerging applications of OTFTs. The primary obstacle to the commercialization of OTFTs is the relatively high operating voltage that results from their high threshold voltage. High permittivity dielectrics are essential for reducing the operating voltage of OTFTs. Another major obstacle to the development of OTFTs, particularly for the manufacturing of flexible electronic circuits and sensors, is the scarcity of high performance n-type organic semiconductors. OTFTs find applications in flexible OLED displays, wearable electronics, sensors for biomedical, AI (artificial intelligence) and IoT (Internet of Things) applications, flexible integrated circuits, neuromorphic computing, smart labels and so on. • Performance overview of Pentacene, C8-BTBT, DNTT and P3HT based OTFTs. • Emerging n-type organic semiconductors for the development of OTFTs. • Highlights the applications of OTFTs. • Deals with various architectures of OTFTs. • Highlights the challenges in the development of OTFTs. [ABSTRACT FROM AUTHOR]

The physical properties of Zr based full-Heusler alloys Zr 2 CoZ (Z = Al, Ga, In) have been studied. In these full Heusler alloys, the ground state properties are computed for both Cu 2 MnAl and Hg 2 CuTi structures. The non-spin polarized and spin polarized calculations predicted that the ferromagnetic ground state energy is less than the non-magnetic ground state energy which shows that these alloys are ferromagnetic in nature. It is found that spin up state is metallic and spin down states have the semiconducting band gaps with the Hg 2 CuTi structure. It shows that these Heusler alloys are half-metallic in the Hg 2 CuTi structure. From the band structure of spin down state, it is observed that these alloys have the indirect band gap in the Hg 2 CuTi structure. The total magnetic moments are calculated to be around 2 μ B for these full Heusler alloys. These alloys obey Slater Pauling rule μ t = Zt -18. The optical properties like dielectric function, refractive index, energy loss function, reflectivity and absorption coefficient and extinction coefficients are computed. The large static dielectric constant values imply their possible use in dielectric purposes. The computed high reflectivity of Zr 2 CoZ at ∼10–15 eV predicted that these alloys are used as coating materials to reduce solar heating. In spintronic devices, these alloys can be used. Fig. 4 Total and partial densities of states of full Heusler alloys Zr 2 CoZ (Z = Al, Ga, In). [Display omitted] • Zr 2 CoZ (Z = Al, Ga,In) Heusler alloys exhibit half metallic ferromagnetism. • Optical properties are analyzed for the first time. • All these alloys exhibit 100% spin polarization. • Total magnetic moment obeys Slater –Pauling rule. [ABSTRACT FROM AUTHOR]

Nano-biosensors (Nano-BSE) belong to the class of BSEs that are being developed with influence from nanotechnology. High surface area nano-materials have played a key role in the development of nano-BSEs with increased sensitivity and faster reaction-times. Understanding biological reactions has become increasingly important in the current context of constantly changing environmental conditions and related variations in homeostatic events. The molecular identification of biomarkers linked to different disease diagnosis is one among the common use of nano-BSE. These sensors have the ability to identify extremely low analyte concentrations, frequently between picomolar and femtomolar. Furthermore, nano-BSE provides unparalleled prospects for multiplexed detection, enabling the identification of numerous biomarkers in a single sample. The effectiveness of the nano-BSE is mostly reliant on the design of the bio-sensing interface due to the heterogeneous reaction between the bio-recognition molecule and analyte. This study focuses on different nano-materials used in the fabrication of nano-BSEs, synthesis techniques of nano-materials and recent advances of nano-BSEs in various biomedical applications. The application of nano-BSEs in SARS-COV2 detection was also comprehensively studied in addition to recent advances of nano-BSEs in various other applications. [ABSTRACT FROM AUTHOR]

The viability of utilizing electron beam evaporation technique for the development of NiTi shape memory alloy (SMA) thin films on kapton polyimide (flexible substrate) has been investigated. The actuation characteristics of the SMA/polyimide structure were evaluated using shape recovery analysis and electrical actuation. The maximum shape recovery ratio of 1.375 was attained with butterfly configuration during shape recovery analysis. The SMA/polyimide stimulated via Joule heating has displayed a maximum displacement of 0.9 mm at 3 V. The surface morphology examined through scanning electron microscope shows the smooth surface without any pores. The thermal stability analyzed using thermogravimetric analysis shows the NiTi SMA thin film can withstand higher temperature above 550 °C without any damage to the SMA/polyimide structure. The stress/strain behavior of the SMA/polyimide structure was analyzed as a function of temperature. The differential scanning calorimetry has showed that the austenite phase transformation temperature lies in the range of 45°C-95 °C. The temperature sweep test performed using dynamic mechanical analyzer recorded a drastic drop in storage modulus in the same phase transformation temperature range as that of DSC. The UV–Vis spectroscopy reveals the NiTi/polyimide structure has high reflective surface in the visible region which aids in the application of reflectors. SMA/polyimide structure can be used as a smart optical mirror in interferometry technique owing to its optical reflectivity. • NiTi Shape Memory Alloy thin film was fabricated using E-beam evaporation technique. • Maximum shape recovery ratio of 1.375 was obtained with butterfly configuration. • Electrical actuation was realized at two different frequencies such as 0.125 Hz and 0.25 Hz. • A maximum displacement of 0.9 mm was obtained through electrical actuation. [ABSTRACT FROM AUTHOR]