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In this article, polarization and depolarization current (PDC) measurement and quantum chemical calculation (QCC) are performed to investigate the impact of nano-filler addition on the space charge characteristics of epoxy (EP)-based polymeric insulation. In this context, single-type and hybrid-type EP composite insulation samples are prepared by incorporating hexagonal boron nitride (h-BN) nanoparticle (NP) along with a combination of h-BN and Al2O3 NPs, respectively. After that, hole and electron de-trapping currents are estimated from experimentally recorded PDC, which shows that the incorporation of nano-fillers results in a suppression of de-trapping of charges (i.e., hole and electron). From the de-trapping current, the distribution of electron and hole traps is estimated, which stipulates the nanofiller-induced modification of the charge mobility in the bulk insulation. Further, QCC analysis reveals that the electron trap depth is 2.18 and 2.26 eV for single-type and hybrid-type nanocomposite (NC) molecules, respectively. However, the trap depth levels of holes are estimated to be 3.34 and 3.02 eV for single-type and hybrid-type NC molecules, respectively. In addition, this article has proposed an approach to studying the impact of nanofiller addition on the intramolecular space charge migration in polymer-based insulation through the distribution of molecular orbital (MO) energy levels and the electron cloud.

The statistical analysis and resistive switching (RS) nature of the HfOx-based flexible resistive RAM (RRAM) with a chalcogenide stack layer and germanium selenium telluride (GST) with different top electrodes (Al, Ag, and In) have been investigated. The Ag and Al electrodes exhibit a self-rectifying gradual interfacial switching, while indium shows strong filamentary nature. The GST, known for its outstanding thermal confinement, drastically enhances switching performance of the RRAM by excellent thermal confinement and oxygen modulation. In Ag-based devices, the analog switching of 1.5- $\mu $ W power is achieved. The current conduction mechanism shows Fowler-Nordheim (FN) tunneling with 0.0324-eV barrier height in Ag devices resulted in a high current increase in low set voltage (~0.3 V). The device also exhibits high temperature (up to $85~^{\circ }$ C) stability, prolonged data retention capabilities (up to $10^{{4}}$ s), and 3000 cycles dc endurance. It also sustains a stable memory window under mechanical flexing (up to 5 mm). The device is also well-adapted for neuromorphic computing applications by demonstrating exceptional synaptic learning characteristics, such as paired-pulse facilitation (PPF), long-term potentiation (LTP), paired-pulse depression (PPD), and long-term depression (LTD).

Epoxy nano-composites along with inorganic nanoparticles as filler, can exhibit excellent properties, such as ameliorated mechanical strength, improved thermal conductivity, enhanced dielectric strength, and reduced dielectric dissipation factors. Therefore, epoxy-based insulation is employed in power transformers, motors, generators, converter transformers, gas-insulated switchgear, and gas-insulated transmission lines. This article aims to review the dielectric and thermal properties of epoxy nano-composites with incorporated inorganic nano-fillers. Proper dispersion of nanoparticles inside the polymer matrix can effectively improve the dielectric strength and thermal properties of epoxy insulation. Excessive dispersion of nano-fillers can cause agglomeration and defects between the fillers and matrix, resulting in insulation problems such as higher dielectric loss and reduced dielectric strength. It is considered that the dispersion of nanoparticles in proper ratio can effectively improve the dielectric properties of epoxy insulation. Therefore, an augmented perception of the nanoparticle–epoxy interfaces in nano-composites can enable a pragmatic analysis of the desired properties, opening new arrays for application.

Electrochemical measurements of the phase and morphology tuned MoO3nanoparticles shows excellent specific capacitance leading to enhancement in hand-crafted solid-state asymmetric supercapacitor performance.

We review spectroscopic methods developed for the determination of magnetic fields in high-energy-density (HED) plasmas. In such plasmas, the common Zeeman-splitting magnetic-field diagnostics are often impeded by various broadening mechanisms of the atomic transitions. The methods described, encompassing atomic transitions in the visible and ultraviolet spectral regions, are applied to the study of imploding plasmas (in a Z-pinch configuration) with and without pre-embedded magnetic fields, relativistic-electron focusing diodes, and plasma-opening switches. The measurements of the magnetic field in side-on observations of cylindrical-plasma configurations that are local in the radial direction despite the light integration along the chordal lines of sight are discussed. The evolution of the magnetic-field distributions obtained, together with the measurements of the plasma temperature and density, allows for studying the plasma dynamics, resistivity, and pressure and energy balance. In particular, for the Z-pinch, an intriguing question on the current flow in the imploding plasma was raised due to the observation that the current during stagnation mainly flows at relatively large radii, outside the stagnation region. For the premagnetized plasma implosions, all three components of the magnetic field (azimuthal, axial, and radial) were measured, yielding the evolution of the current flow and the efficiency of the axial field compression, as well as the relation between the geometry of the field and the plasma rotation, found to develop in this configuration. The measurements in the relativistic electron diode are used to quantify the shielding of the magnetic field by the plasmas in the diode. Also described are the experimental and theoretical investigations of a nondiffusive fast penetration of magnetic field into a low-density plasma (in the plasma-opening-switch configuration).

An indoor visible light positioning system using the received signal strength intensity method and the trilateration technique with user mobility support is proposed for applications, e.g. healthcare. Accurate position information of medical staffs and patients is required for data transmission, tracking, navigation, etc. Seamless data transmission while user is on the move has been conceptualized considering the optical network formed by photosensor (light emitting diode)-based transmitters. Efficiency of these services depends on the position accuracy. To investigate factors contributing to higher position errors in a practical environment, the proposed system is evaluated. Evaluation is done through simulation and experiment for different channel conditions, and the receiver rotation due to user mobility. Simulation results show an average two-dimensional position error of 0.32 m in a channel with a strong background light illumination level of − 60 dBm. Experimental results show that the mean position error is 0.7 m in a normal daytime indoor light condition.

Analyzing the performance of fiber laser micro-marking on aluminium alloy under focus–defocus conditions entails determining the way varying the focus position during the marking process impacts the overall performance. A special process variable defocus height refers to the distance between the focal point of the laser beam and the surface of the material being marked. In micro-marking, the focal point can be moved above or below the surface to generate distinct effects. The paper determines the optimal parameters for laser micro-marking on aluminium 7075 alloy, including laser power, pulse frequency, scan speed, defocus height (the distance between the top surface and the focal point), and duty cycle, for mark quality and characteristics such as depth and mark width. Experimental results showcase that laser parameters affect mark width and depth nonlinearly. In addition, small variations in laser power, scanning speed, or focus height, have led to moderate changes in dimensions of the mark geometry. A target mark of 40μm in width and 25μm in depth is achieved by combining optimum settings like a power of 23.862w, a duty factor of 45%, a pulse frequency of 76.0506Khz, a scanning speed of 0.70mm/s, and a defocus height of 0.7mm.

ABSTRACTThis paper analyses the outage performance of a multihop relay-based cognitive radio network under imperfect channel state information. A backoff power control scheme is applied to ensure both the quality of service (QoS) and interference constraints of the primary network. To reduce the interference at the primary network, we have proposed a new multihop transmission method where a relay node forwards the signal to the next relay node only when the signal is decoded successfully and QoS of the primary network is satisfied. Unlike the conventional relay transmission scheme, in our system model, a relay node receives signals not only from the previous node but also from the previous-to-previous node. The selection combining (SC) and maximum ratio combining (MRC) diversity schemes are applied to enhance the outage performance of the secondary network. The Monte Carlo simulation is adopted to validate the analysis. It is observed from the simulation results that the outage probability of the secondary network and interference probability of the primary network are impacted by the correlation coefficient between real and estimated channels, the number of hops and the backoff power coefficient.

Data analysis is carried out for four detector stacks composed of passive Lexan polycarbonate detectors exposed in space by the Ultra Heavy Cosmic Ray Experiment on board NASA’s Long Duration Exposure Facility. Scanning and analysis of the 0.21 m2detector area resulted in the finding of 72 ultra heavy (68 ≤ Z ≤ 96) cosmic ray nuclei. About 15% of the cosmic ray nuclei show charge fragmentation within the detector stack of 5.6 g × cm–2. A detailed analysis of these fragmented cosmic ray nuclei is presented, including a discussion within the context of “physical anomalons”. This last term, describing a sub-set of all anomalon phenomena, is defined in the text.

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Background: Protium serratum Engl (Indian red pear) and Artocarpus chama Buch.- Ham (wild jackfruit) are typical wild edible fruits that have a wide range of folk medicinal properties. Objectives: Our present study deals with the exploration of nutritional value, antioxidant activity, and total phenolic content present in Protium serratum Engl and Artocarpus chama Buch.-Ham fruits. Methods: The soxhlet apparatus was used to extract crude samples. The quantitative analysis of the wild edible fruits was broadly done by proximate and ultimate analysis techniques. Results: The results showed that the moisture contents in P. serratum and A. chama Buch. are 78.53% and 74.23%, respectively. The obtained ash (8.59%), fiber (3.17%), total sugar (5.495 mg/100g), and fat (0.66%) contents are high in P. serratum. In contrast, A. chama Buch. has a high content of protein (0.52%). Vitamin C content is higher in P. serratum (550 mg/100g) than that in A. chama Buch. (350 mg/100g). The result shows that the Ca and Mg contents are higher in P. serratum compared to A. chama Buch. Indian red pear shows good antioxidant properties and has high total phenolic content as compared to wild jackfruit and some commercial fruits. Conclusion: The study establishes that further investigation must be done to determine the development of new products, processing, and preservation techniques so that two underutilized fruits can become a part of our regular dietary habits. By doing so, we can enrich the fruit basket of the country.

Multilevel inverters (MLIs) have received a significant attention in literature due to advent of various topologies utilising power semiconductor switches with reduced voltage stress. However, the increased component count and susceptible nature of semiconductor components increase the chance of failure in inverter. The fault in power switches, either open circuit or short circuit, if persist for long time may result in complete system shutdown. This damage can be avoided by detecting and diagnosing the fault in less period of time to continue the healthy operation. The present paper studies an open-circuit fault detection method on conventional five-level NPC inverter topology with output voltage waveform analysis by discrete wavelet packet transform (DWPT) and classifying the fault location by artificial neural network (ANN). The strategy to tolerate both abovementioned type of failure on any location after detection is proposed by implementing a novel redundant architecture in conventional five-level inverter. This architecture has an advantage of utilising less device count to tolerate fault on single as well as multiple switch combinations. The proposed work is studied in MATLAB/Simulink and validated experimentally.

This study probably for the first-time introduced a phase and morphology-tuned scalable, cost-effective method for large-scale production of Black Phosphorous/Phosphorene (BP), and investigated their in-depth electrochemical properties. Utilizing a one-pot mild wet chemical-assisted hydrothermal route in ethylenediamine, high-quality BP nanosheets were synthesized from amorphous red phosphorus (RP) with nearly 100 % conversion efficiency, yielding 7.1352 g for one batch at 130–170 °C. The resulting phosphorene nanosheets exhibited a small crystalline size (2.708 nm), hierarchically porous morphology, a 1.64 eV direct optical bandgap aligned with theoretically calculated bandgap using LDA approximation, and various structural defects, along with large specific surface area (50 m2g−1) and reduced number of layers (4–5) compared to prior literatures, suggesting electrochemical superiority. CV and GCD measurements in the potential window of −0.7 V to 0.1 V revealed its highest pseudo-capacitance response (84.91 %), reaching a maximum specific capacitance value of 759.748 Fg−1at current density 2 Ag−1, surpassing all previous records. Moreover, BP displayed excellent cyclic stability of 89.8 % after 10,000 cycles, making it an excellent electrode material for supercapacitors. A solid-state asymmetric supercapacitor device (HASD), using BP, successfully lighted up 6 red LEDs for 10 s, achieving maximum specific energy density at 73.43 Wkg−1at a power density of 1500 Wkg−1.

Breeding for quality traits in tomato has got boost due to enormous consumer and industrial demand owing to its exceptional nutritional benefits and attributes required for processing industries. Newly evolved varieties/hybrids need recommendation based on their adaptive specificity as a consequence of genotype-environment interaction. Hence, present study analysed comparative stability of 30 hybrids of tomato along with one check hybrid (To 3150) for important quality traits viz., total soluble solids (TSS), titrable acidity, ascorbic acid, carotene and lycopene content based on data of three locations over two years. The identified stable hybrids were Columbia × EC 538380, H 86 × EC 620541 and EC 620541 × EC 620438) for TSS, Superbug × EC 620438 for titrable acidity, Columbia × EC 620438 for ascorbic acid and NDTVR 73 × EC 620541 for carotene content. None of the hybrids was found stable for lycopene content. Stability for one trait was independent of stability of other traits. The responsive hybrids were Columbia × BS 24–2 (for TSS and carotene content), EC 521087 × EC 538380 (for ascorbic acid and carotene content), EC 620438 × EC 538380 (for ascorbic acid, carotene and lycopene content). The environments of Varanasi during both the years had favourable effect on all quality traits except carotene content as evident from environmental indices. The hybrids identified as stable are broad-adapted and can be recommended for general cultivation under different locations while the hybrids identified as responsive can be recommended for specific environments only.

Congenital and childhood cataracts are uncommon but regularly seen in the clinics of most paediatric ophthalmology teams in the UK. They are often associated with profound visual loss and a large proportion have a genetic aetiology, some with significant extra-ocular comorbidities. Optimal diagnosis and treatment typically require close collaboration within multidisciplinary teams. Surgery remains the mainstay of treatment. A variety of surgical techniques, timings of intervention and options for optical correction have been advocated making management seem complex for those seeing affected children infrequently. This paper summarises the proceedings of two recent RCOphth paediatric cataract study days, provides a literature review and describes the current UK ‘state of play’ in the management of paediatric cataracts.

In this study, we have successfully synthesized ZnMnO3(ZMO) nanostructures with precisely controlled morphology and crystallinity through an advanced co-precipitation procedure and thoroughly investigated their electrochemical performance. Our approach introduced a novel, polymer-assisted synthesis process with sintering temperature variations (400–600 °C), leading to a phase transition from amorphous to moderate to highly crystalline spherical morphology. The nanostructures obtained by sintering at 500 °C (ZMO5) exhibited high porosity, exceptional crystallinity and a significantly enlarged specific surface area compared to existing reports. The Cyclic voltammetry and Galvano-potentiometry measurements for mass-optimized ZMO5 working electrode revealed excellent pseudo-capacitive behavior, achieving a maximum specific capacitance of 1755.31 Fg−1at 1 Ag−1. Furthermore, ZMO5 exhibited outstanding cyclic stability, retaining about 92.4 % of its performance after 2000 cycles. To demonstrate practical utility, we constructed a solid-state asymmetric supercapacitor device using ZMO5. The device exhibited a maximum specific energy density of 182 W h kg−1at a power density of 1800 W kg−1, and high cyclic stability of 84.67 % after 2000 cycles, showcasing its efficiency in energy storage applications.

A transmitted frame in a wireless sensor network (WSN) may get corrupted due to erroneous bits in the frame, an event characterized at the physical (PHY) layer. The frame may also get dropped at medium access control (MAC) layer due to collision with other frames. As energy is wasted due to both, a combined cross-layer (PHY + MAC) model is needed for evaluating the energy for every successful transmission at frame/bit level. The model would also help in assessing how greena technique is, which might be proposed for PHY/ MAC layer of any WSN, by computing the improvement in energy efficiency. In this paper, we present a cross-layer energy model for communication in beacon-enabled 802.15.4 networks operating in star topology. IEEE 802.15.4 is the worldwide accepted WSN standard. Further, for status monitoring and event detection, which are the most common low data rate WSN applications, sensor nodes form a star topology where a central node sends periodic beacons to access data from all other nodes. Our model includes energy consumption for both source and destination node during the actual frame transmission as well as during the operations that precede frame transmission such as backoff and clear channel assessment (CCA). A two dimensional Markov model has been adopted for the purpose and parameters like average number of backoffs and average number of CCAs have been computed. Finally, the energy consumption per successful bit transmission is found by combining the collision probability in MAC layer and error probability in PHY layer. The results revealed that while the number of nodes in a WSN does not affect the energy consumption much, the frame length has a huge influence. Also, energy consumption rises considerably when acknowledgement is opted for.

This work introduces a cost-effective method to synthesize carbon nanofibers (CNFs) at a lower temperature (∼100 °C), addressing the synthesis cost and precursor selection challenges associated with traditional methods requiring temperatures of ⁓3000 °C. Acid-etched banana fibers served as sustainable precursors, while KClO3acted as a liquid carbonization medium. The resulting CNFs (referred MCCNFs), exhibited hollow structures with intertwined tubular morphology (OD ∼20–40 nm and ID∼ 5–10 nm). They possessed a hexagonal porous structure (P63/mmc) with a high specific surface area (152.09 m2g-1), significant pore volume (0.459 ccg−1), and impressive tensile strength exceeding 2.71 TPa. Smaller intensity ratio of D and G bands (0.396) confirmed their purity and structural integrity. MCCNFs displayed semi-metallic behaviour with superior electrical conductivity (0.0386 S-m−1), validated by ab initioelectronic band structure calculations. UV–vis absorption spectra revealed a linear band structure. Notably, MCCNFs displayed a record-breaking capacitance of 1412.5 Fg-1at 5 Ag-1, making them promising for supercapacitor electrode applications. Furthermore, these CNFs were used to fabricate a flexible all-solid-state supercapacitor, successfully powering 6 LEDs for 10 s. Hence, this work set a pave for low-cost, low-temperature synthesis of CNFs having superior physical and chemical properties and immense promise for advancing energy storage applications.

The impact of influenza virus infection is felt each year on a global scale when approximately 5–10% of adults and 20–30% of children globally are infected. While vaccination is the primary strategy for influenza prevention, there are a number of likely scenarios for which vaccination is inadequate, making the development of effective antiviral agents of utmost importance. Anti-influenza treatments with innovative mechanisms of action are critical in the face of emerging viral resistance to the existing drugs. These new antiviral agents are urgently needed to address future epidemic (or pandemic) influenza and are critical for the immune-compromised cohort who cannot be vaccinated. We have previously shown that lipid tagged peptides derived from the C-terminal region of influenza hemagglutinin (HA) were effective influenza fusion inhibitors. In this study, we modified the influenza fusion inhibitors by adding a cell penetrating peptide sequence to promote intracellular targeting. These fusion-inhibiting peptides self-assemble into ∼15–30 nm nanoparticles (NPs), target relevant infectious tissues in vivo, and reduce viral infectivity upon interaction with the cell membrane. Overall, our data show that the CPP and the lipid moiety are both required for efficient biodistribution, fusion inhibition, and efficacy in vivo.

The phase transition of chemically synthesized MoS2nanocrystals (NCs) from the metallic 1T to the semiconducting 2H phase has been investigated in detail. The metallic 1T phase NCs were prepared by the Li+intercalation–deintercalation exfoliation techniques followed by prolonged sonication. The effect of ex situ thermal annealing on MoS2polymorphs and their transformation from the 1T to 2H phase has been extensively monitored by the X-ray photoelectron, Raman, and optical absorption spectroscopy techniques. Electrical conductivity measurements have also been carried out to probe the phase transition of the synthesized NCs. The temperature-dependent (10–350 K) electrical charge transport properties of variable-sized NCs have been investigated to probe the scaling of conductivity and activation energy with size, which are yet to be reported experimentally. The charge transport mechanisms through the NC assembly for different temperature regions have been modeled and it is observed that the electron transport undergoes a transition from the nearest-neighbor hopping to the variable range hopping upon decreasing temperature.

Dairy manure is regularly applied to crop fields as a solid or liquid to improve the soil nutrient status. However, pathogens may survive during manure storage and enter the environment during application. In this study, three storage practices were evaluated to understand the survival patterns of Eschericia coliO157:H7 and Listeriaspp. in dairy manure using a culture‐based approach. To replicate common farm manure storage techniques, solid manure was stacked as piles with periodic turning or as static piles without turning, whereas liquid manure (feces, urine, and water) was stored as a slurry in small tanks to simulate lagoon conditions. The E. coliand Listerialevels in the manure samples were determined for 29 wk. Results showed that there was an initial reduction in bacteria levels in the first month; however, both E. coliand Listeriamanaged to survive in the solid manure piles for the full study period. In slurry samples, E. coliwas not detected after 14 wk, but Listeriasurvived until the end of the experiment at relatively lower levels than in the solid manure piles. Ambient weather and pile size were identified as the main reasons for bacteria survival during the course of the experiment. The outcome of this study is important in terms of understanding pathogen survival in manure piles and slurries prior to their application to crop fields. Solid and liquid dairy manure storage conditions on pathogen decay were investigated.E. coliO157:H7 and Listeriaspp. survived in solid manure up to 6 months.Pile size and temperature are factors that likely influenced pathogen survival.

PurposeTo investigate whether the observed international differences in retinopathy of prematurity (ROP) treatment rates within the Benefits of Oxygen Saturation Targeting (BOOST) II trials might have been caused by international variation in ROP disease grading.MethodsGroups of BOOST II trial ophthalmologists in UK, Australia, and New Zealand (ANZ), and an international reference group (INT) used a web based system to grade a selection of RetCam images of ROP acquired during the BOOST II UK trial. Rates of decisions to treat, plus disease grading, ROP stage grading, ROP zone grading, inter-observer variation within groups and intra-observer variation within groups were measured.ResultsForty-two eye examinations were graded. UK ophthalmologists diagnosed treat-requiring ROP more frequently than ANZ ophthalmologists, 13.9 (3.49) compared to 9.4 (4.46) eye examinations, P=0.038. UK ophthalmologists diagnosed plus disease more frequently than ANZ ophthalmologists, 14.1 (6.23) compared to 8.5 (3.24) eye examinations, P=0.021. ANZ ophthalmologists diagnosed stage 2 ROP more frequently than UK ophthalmologists, 20.2 (5.8) compared to 12.7 (7.1) eye examinations, P=0.026. There were no other significant differences in the grading of ROP stage or zone. Inter-observer variation was higher within the UK group than within the ANZ group. Intra-observer variation was low in both groups.ConclusionsWe have found evidence of international variation in the diagnosis of treatment-requiring ROP. Improved standardisation of the diagnosis of treatment-requiring ROP is required. Measures might include improved training in the grading of ROP, using an international approach, and further development of ROP image analysis software.

Here, we report a novel approach towards bulk scale manufacturing of metallic foams with uniform distribution of open-cells for designing high pressure hydrogen storage tanks. The manufacturing technique provides a cost effective and comparatively easy way of processing open-cell foam structures of a wide range of metals and alloys. In addition, the process allows a precise control over the shape and size of the pores and ensures a uniform distribution of the pores in these metallic structures. The fabrication process involves a pressurized casting of molten metals/alloys over pre-fabricated salt patterns/preforms. The porous metallic structures are recovered by leaching out the salt patterns.