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In this paper we have developed an analytical model for Ferro PZT Al2O3/AlGaN/AlN/GaN MOSHEMT involving the solution of Poisson and Schrodinger equations. This analytical model covers most of the operating¨ regimes of the Ferro PZT MOSHEMT. The two-dimensional electron gas (2-DEG) sheet charge density (ns), threshold voltage (Vth), drain current (Ids), gate capacitance (Cgs and Cgd), and unit gain cut-off frequency(fT) model equations are generated and simulated with MATLAB tool. It is also observed that the insertion of the Ferro Pb(Zr, Ti)O3 PZT (lead zirconium titanate) material can also improve the device performance. The proposed Ferro PZT MOSHEMT model accurately produces a higher drain current of 1.14A/mm, a high transconductance of 362S/mm, the gate-to-source capacitance of 50.99pF, the gate-to-drain capacitance of 38.25pF, and high cut-off frequency of 0.033THz for 20nm AlGaN barrier layer. The proposed model results show good agreement with the TCAD-Atlas simulation results and were satisfactory for the different AlGaN barrier layer thickness. The generated model and simulation results show the potential of using the Ferro PZT MOSHEMT for high-power and RF/Microwave applications.

Supraglottic devices like laryngeal mask airway (LMA) is used in children for anesthesia as it induces least hemodynamic stress response. We have carried out this trial to measure the potency of induction agents like propofol with sevoflurane for conditions of LMA placement in pediatric surgery. 60 children were included in our study and were split into two groups. Children in group S were induced with sevoflurane 8vol%. Children in group P were induced with propofol at 3 mg/kg IV. Proper size of LMA was inserted. Induction time, insertion time, LMA placement conditions and hemodynamic abnormalities were assessed. Induction time was shorter with group P contrary to S group. (p0.05) There was no remarkable difference in various LMA insertion conditions and LMA insertion score in both groups. Hemodynamic changes were comparable in group S and P. Propofol and sevoflurane revealed equivalent and suitable LMA placement settings. So propofol may be a good substitute to sevoflurane for placement of LMA in children in a recourse limited setting. Keywords: Sevoflurane, Propofol, Laryngeal mask airway, Children.

In this article, the Authors have demonstrated and analyzed various analog/RF and linearity performance of a AlGaN/GaN gate recessed MOSHEMT (GR-MOSHEMT) grown on a Si substrate with mathematical modeling based TCAD simulation. Specifically, a Al2O3 dielectric GR-MOSHEMT has shown tremendous potential in terms of AC/DC figure of merits (FOM’s) such as low leakage current, high transconductance, high Ion/Ioff current ratio and excellent linear properties corresponding to conventional AlGaN/GaN HEMT and MOSHEMT. The figure-of-merit metrics such as VIP2, VIP3, IIP3 and IDM3 are performed for different drain to source voltages (VDS) of 2.5V, 5V and 10V. All the modeling and simulation results are generated by Commercial Silvaco TCAD and found to be satisfactory in terms of high frequency and power applications. The present GR-MOSHEMT device shows a superior performance with a threshold voltage of 0.5V, Current density of 888 mA, high transconductance of 225 mS/mm and high unit gain cut-off frequency of 0.91GHz. The results of the developed AlGaN/GaN GR-MOSHEMT considerably improves the device performance and also suitable for high power distortion less RF applications.

ABO incompatibility between O blood group mother and non–O blood group neonate is common. It rarely causes anemia and hyperbilirubinemia in neonate, requiring invasive management. Direct antiglobulin test may be positive in these cases with immunoglobulin (Ig)-G antibody specificity. There are few cases of hemolytic disease of newborn due to ABO incompatibility between mother and newborn with non ̶ O blood group mother. After obtaining consent from the patient, we reported a case of incompatibility in a B blood group mother and A blood group neonate, and it was managed with phototherapy.

Background and Aims Etomidate, an intravenous (IV) induction agent known for its stable myocardial action, can produce myoclonus which can be detrimental for the cardiac patients. Though lignocaine has proven its efficacy in attenuating the etomidate-induced myoclonus, the ideal dose of lignocaine is not known. The aim of our trial was to analyze two different doses of lignocaine on the occurrence and intensity of etomidate induced myoclonus. Materials and Methods A total of 120 patients were randomly assigned into three groups of 40 each. Patients in group A were injected lignocaine 0.5 mg/kg intravenously, group-B patients were injected lignocaine 1 mg/kg intravenously, and group-C patients were injected saline placebo. After 2 minutes, anesthesia was induced with 0.3 mg/kg of etomidate over 30 seconds. The patients were assessed for myoclonus using clinical severity scoring system during first 2 minutes of induction. Our primary outcome was the incidence of myoclonus. The severity of myoclonus and adverse effects were the secondary outcomes. Results No remarkable variation was found regarding demographic profile among three groups. Incidence of myoclonus in groups A and B was 35% and in group C was 98%, the difference being statistically significant. Both doses of lignocaine reduced the severity of myoclonus up to same extent. Conclusion Pretreatment with IV lignocaine 0.5mg/kg and 1 mg/kg IV remarkably decreased the occurrence and severity of myoclonus induced by etomidate up to same extent.

Quantum engineering in kesterite solar cells reveals a blending advancement keeping in mind that copper zinc tin sulfide (CZTS)-based material requires high-research implementation as a replacement for copper indium gallium selenide (CIGS) materials. In this article, quantum well-solar cells (QWSCs) on kesterite material is proposed in which CZTS x Se1− x and CZTS material is taken as well and barrier materials with different Sulfur (S) and Selenium (Se) content. All the optical, electrical, and material properties are investigated in detail to achieve high efficiency. The focus on the incorporation of a high number of quantum wells (QWs) (2 to 100 QWs) and performance analysis show the uniqueness of the study. Quantum efficiency (QE) of the solar cell with separate internal and external absorptions is also investigated here. Different issues on carrier propagation, recombination, and collection are emphasized to highlight the effect of carrier quantization in the material. A remarkable efficiency of 38% with 88% fill factor (FF) could be achieved from the broad range of the proposed structure, which may show a new path for next-generation solar cells.

Quantum engineering in kesterite solar cells reveals a blending advancement keeping in mind that copper–zinc–tin–sulfide (CZTS)-based material requires high-research implementation as a replacement for CIGS materials. In this article, a quantum-dot-embedded kesterite solar cell is proposed, in which CZTS x $\text{Se}1-_{x}$ and CZTS are taken as dot and barrier, respectively, with different sulfur (S) and selenium (Se) content. Focus is given on the incorporation of quantum dots (QDs) and a detailed investigation is carried out through optical and electrical performance, which shows the uniqueness of this study. Quantum efficiency of the solar cell with separate internal and external absorption is also investigated. Different issues on carrier propagation, recombination, and collection are emphasized to highlight the effect of carrier quantization in material. The reliability analysis of the solar cell is also a new scope to investigate the trap-assisted recombination. The detail analysis and remarkable efficiency may bring a new path for next-generation solar cells.

Kesterite materials Cu2ZnSn(SxSe1−x)4, Cu2ZnSnS4 and Cu2ZnSnSe4 have received considerable attention as absorber layers for photovoltaic cell applications. But they exhibit efficiencies lower than 12%. In this work, different possible loss mechanisms that affect the solar cell performance are analysed. Numerical investigation is made on the influence of different loss mechanisms such as radiative recombination, presence of traps and defect densities on the performance of the device. A comparative between results on solar cells based on Cu2ZnSnS4 and Cu2ZnSnSe4 absorber layers is presented. The recombination mechanisms are found to play a vital role in degrading the performance of the solar cell. Additionally, trap centers and density of defect states are distributed to the absorber layer. It is observed that efficiency of the solar cell is severely affected and degraded by 10 % in the presence of defect states.

Thiamethoxam is a neonicotinoid group of insecticide which are selective agonists of the insect nicotinic acetylcholine receptor (nAChR), a pentameric cys-loop ligand-gated ion channel located in the central nervous system of insects. They provide farmers with invaluable, highly effective tools against some of the world’s most destructive crop pests. Black legume aphids, Aphis craccivora is one of the devastating polyphagous pests in agroecosystem and to manage their population, farmers are still relying on application of synthetic insecticides like Thiamethoxam. To evaluate the risk of resistance development, selection of A. craccivora was done to characterize Thiamethoxam resistance along with evaluation of developmental and reproductive fitness cost of the resistance. About 86.19 folds of resistance were developed after selecting for 24 generations. In the first twelve generations steady development of resistance was noticed followed by development become stiffer till 16th generation and more or less stable till 24th generations. Relative fitness of the selected resistant strain of aphids was decreased with longer nymphal duration and adult longevity. The mean nymphal duration was increased from 4.35±1.02 days (in F0) to 7.9±0.57 days (in F24). The fecundity rate was significantly less in resistant population (16.0±5.34) as compared to the susceptible strain (54.71±7.63) whereas, oviposition periods were significantly longer (12.49±1.44 days) in resistant population as compare to susceptible strain (9.50±1.22 days).

In this article, GaN/ InxGa1 − xN based solar cell with Si substrate and SiCN buffer layer is investigated with the help of modeling and simulation. The performance of the designed device is best suited for the low cost photovoltaic applications in terms of high open-circuit voltage (VOC) of 2.53 V, short-circuit current density (JSC) of 2.83 mA/cm2, Fill Factor (FF) of 76.98% and power conversion efficiency (η) of 4.02% under air mass (AM) 1.5G illumination. The mole fraction of Indium content in InxGa1 − xN plays a significant role in increasing the efficiency and open circuit voltage for improved device performance. A commercial Silvaco TCAD is used for simulation of GaN/InxGa1 − xN based solar cell for extracting the energy band gap, short-circuit current density, power (P) and the power conversion efficiency with different design parameters.

In this paper, we simulated a new line tunnel field-effect transistor (TFET) with a Z-shaped gate. The proposed Z-TFET generates vertical tunneling due to the presence of the front gate over the entire source region. This generates faster tunneling between the source and the channel region, providing a 3-decade improvement in drain current compared to conventional DG-TFET. The ambipolar current is also improved by 1-decade with a subthreshold swing (SS) of 40 mV/decade (reduces by 18%). Further optimization of the front and back gate is performed to investigate its impact on the analog performance of Z-TFET. The simulated results exhibit improvement in ambipolar current, reduction in OFF current by optimizing the back-gate length. This simulation work is performed in the presence of field-induced quantum confinement using the TCAD device simulator. Additional reliability issue of the structure in the presence of the interface trap charge at the semiconductor-oxide interface is properly investigated. The effect of trap charge density (Nf) and capture cross-section (σ) variation on the transfer characteristics and average SS has been examined. The proposed device can provide a higher ION/IOFF of 1013 and ION/IAMB of 107.

Individuals with the rare para-Bombay phenotype have inherited defects in producing H associated with FUT1 and/or FUT2 genes. We report a case of blood group discrepancy in a para-Bombay patient from a tertiary care hospital of eastern India. A 31-year-old woman with rheumatic heart disease presented with fatigue and breathlessness and was then scheduled for valvuloplasty, for which a blood transfusion request was sent to the blood center. During pre-transfusion testing, red blood cell (RBC) testing showed group O, and serum testing showed strong reactivity with group B RBCs, weak reactivity with group O RBCs, and very weak reactivity with group A RBCs. Saliva inhibition testing and enzyme treatment of RBCs concluded the patient to be of “Ah para-Bombay” phenotype. The patient’s Lewis phenotype was Le(a–b+). This patient’s serum also had cold-reacting anti-IH along with anti-B. This case report highlights the importance of performing an advanced immunohematologic workup, including adsorption, elution, enzyme treatment, and saliva inhibition testing for identification of weak A or B subgroups as well as the rare para-Bombay blood group, when routine ABO typing, using forward and reverse grouping, is inconclusive. Accurate identification of blood group helps in preventing transfusion-related adverse events and encouraging safe transfusion practice.

A new Ge/SiGe heterojunction double-gate tunnel field effect transistor (DGT) model with hetero dielectric gate and Gaussian doping drain region is investigated for the first time. The introduction of heterojunction with hetero dielectric will reduce band-to-band tunneling (BTBT) leakage current while maintaining high mobility to enhance drain current and transconductance characteristics of the device significantly. Along with that, the combined effect of analytical drain doping profile (Gaussian) and hetero dielectric suppresses the ambipolar behavior. Different DC characteristics of the device like energy band analysis, electric field, drain current and BTBT generation rate are analyzed for the proposed structure. RF figure of merit for the HD-HJDGT-GD is express by analyzing its transconductance (gm), cut off frequency (fT), maximum oscillation frequency (fmax), gain bandwidth product (GBP) and transconductance frequency product (TFP). The outcome of the model under study is compared with conventional DGT. It is apparent from the analysis that the recommended model has better DC and RF performance, which makes this device worth studying to be used in high-frequency applications. TCAD simulation is performed by using Sentaurus 2D device simulator from Synopsys.

FinFET structures of 10 nm technology node with promising design enhancements like hybrid spacer, raised source and drain extensions, and silicide interfaces have been analysed and compared. Analog figures of merit like drain current, transconductance, intrinsic gain, and transconductance generation factor are determined here. Furthermore, RF figures of merit like cut-off frequency, intrinsic delay, and gate capacitance are analysed. These parameters have been determined at three different temperatures (200 K, 300 K, 400 K) to study the effect of temperature on device performance.

In III-Nitride planar photosensitive devices (PSDs), proper engineering in polarization charges (PCs) are required in order to reduce detrimental effects on the devices. In this work, piezo-phototronic effects of PSDs are explored, giving more emphasis on photovoltaic application. The polarization effects of GaN/In x Ga1– x N multiple quantum wells on planar solar cell with {000-1} or {0001} as one of the facets are intensively studied through numerical simulations. Analysis of PCs both in simulation and theoretical model at different facets of solar cell with different ‘In’ compositions are considered carefully. It is observed that planar PSDs with reversed polar {000-1} facet is good enough to enhance the carrier dynamics of solar cell in quasi neutral region as compared to normal polarization {0001} facet. This numerical study provides an innovative aspect of implementation of fundamental device physics with respect to recent growth techniques in order to realize the application of III-Nitride PSDs towards photovoltaic applications. The effect of GaN/In x Ga1– x N layer with different ‘In’ compositions in all crystallographic orientations of planar solar cell are also discussed. A conversion efficiency of 21% with 74% fill factor is achieved from strain modulated four quantum well based solar cell considering 10% of ‘In’ content under one sun AM1.5G illumination.

One of the most important criteria to design more than 30% efficient III–V compound/Si based dual junction solar cell is that we must design atleast 20% efficient III–V compound material top cell. In this regard, we designed a bandgap engineered GaAs0.95P0.05 single junction solar cell with reduced bandgap of (E g ) = 1.48 eV. Reducing the bandgap from 1.72 eV to 1.48 eV for GaAs0.95P0.05 cell leads to generate higher short circuit current, while having the tradeoff with the open circuit voltage. Due to small change in lattice constant of GaAs0.95P0.05 cell, some recombination is observed near the junction area. Although the minimal degradation is observed in open circuit voltage, the higher short circuit current drives the overall efficiency of the GaAs0.95P0.05 single junction solar cell. The designed solar cell provides an extended internal absorption for longer wavelength of spectrum. The high electron mobility of 8500 cm2 V–S−1 was observed with very high electron to hole mobility ratio of 21.25. The optimization of the cell is done using two back surface field layers (AlInP and AlGaInP) of higher bandgap material. The high short circuit current density of J SC = 25.93 mA cm−2 with V OC = 1.1635 V achieved by the designed cell with the highest efficiency of η = 25%. The solar cell is irradiated under 1-Sun solar irradiation in the AM1.5 G environment providing 1000 W m−2 of power spectral density. The External and Internal Quantum efficiency of more than 95% is achieved by the designed solar cell.

The key attributes of double hetero junction tandem solar cell based on III-Nitride alloys and silicon is investigated thoroughly. GaN/InGaN/GaN based tandem solar cells are predicting impressive efficiency, however due to its high cost; it is far from immediate implementation. Hence, an attempt is made to realize GaN/InGaN on crystalline silicon(c-Si) substrate that results in high spectral efficiency and cost effectiveness. The proposed multi-junction tandem solar cell consists of a GaN layer, intrinsic-InxGa1−xN (i-InGaN), tandem InxGa1−xN (t-InGaN) upon crystalline p-silicon and n-silicon layers. Energy band diagrams, current-voltage curve, power graph, electric field and potential graphs are explored using TCAD tool. Additionally, key parameters such as ’In’ content, thickness of layers, absorption coefficients, polarization charges are optimized. A remarkable conversion efficiency of 25.6% and 26.1% are achieved with & without polarization effect, respectively and became a potential candidate for next-generation photovoltaics applications.

The innovative contribution of this paper is to derive polarization charges in hexagonal and triangular GaN/InGaN/GaN core/shell/shell nanowire solar cells considering effect of degree of strain relaxation (R) and appropriate stiffness coefficients. The crystal orientation angle, φ and non-linear effect of spontaneous polarization are tailored with strain calculations for a better precision of polarization charges in nanowire type devices. The article also formulated the effect of polarization charges while InGaN layers are grown above or below GaN layer in both types of nanowires depending on the lattice expansion or compression. The model accounts an innovative concept of polarization charges distribution with respect to growth of crystal orientation and strain relaxation. It is observed that nanowire solar cell with triangular geometry could be good enough for efficient generation of power as compared to hexagonal nanowire solar cell. This concept of one triangular nanowire solar cell exhibits an efficiency of 3.18% with 90.34% fill factor under 1 Sun AM1.5 illumination with 20% ‘In’ composition.

Photovoltaic (PV) technology could be a promising candidate for clean and green source of energy. The nanowire technology provides extra mileage over planar solar cells in every step from photon absorption to current generation. Indium Gallium Nitride (InxGa1-xN) is a recently revised material with such a bandgap to absorb nearly whole solar spectrum to increase the conversion efficiency copiously. One of the major technological challenge is in-built polarization charges. This chapter highlights the basic advantageous properties of InxGa 1−xN materials, its growth technology and state-of-the-art application towards PV devices. The most important challenges that remain in realizing a high-efficiency InxGa 1−xN PV device are also discussed. III-Nitride nanowires are also explored in detail to overcome the challenges. Finally, conclusions are drawn about the potential and future aspect of InxGa 1−xN material based nanowires towards terrestrial as well as space photovoltaic applications.

In Quantum Well (QW) solar cells, modulation of in built piezo-phototronics mechanism are required in order to enhance performance of solar cell. In this work, the polarization effects of $\mathrm{GaN}/\mathrm{In}_{x}\mathrm{Ga}_{1-x}\mathrm{N}$ multiple quantum well planar solar cell with different orientational dependent facets are intensively studied through numerical simulations. Analysis of polarization charges both in simulation and theoretical at different facets of solar cell with different ‘In’ compositions are considered carefully. It is observed that QW solar cell with reversed polar {000-1} facet is good enough to enhance the collection efficiency of solar cell in quasi neutral region as compared to normal polarization {0001} facet. This numerical study provides a different aspect of engineering the fundamental device physics with respect to recent growth techniques in order to realize the application of III-Nitride nanowires towards photovoltaic applications. The effect of $\mathrm{GaN}/\mathrm{In}_{x}\mathrm{Ga}_{1-x}\mathrm{N}$ layer with different ‘In’ compositions in all crystallographic orientations of nanowire solar cells are also discussed. A conversion efficiency of more than 16% with 76% fill factor and 82% quantum efficiency is achieved from strain modulated dual QW based solar cell considering 10% of ‘In’ content under one Sun AM1.5 illumination.

Si solar cell based on carrier selective contact and tunnel oxide passivated contact (TOPCon) show great promise toward reaching the Shockly-Quiesser (SQ) limit. The carrier selective transport provides lower recombination and hence increases the external Voc. In this work a thin oxide layer is introduced which will act as a carrier selective layer and carriers will tunnel through it. The tunnel oxide provides tunneling and transport through the pinholes. The electric field effect in the oxide due to pinholes increases the carrier transport. The passivation reduces the recombination at the contact which results in the reduced resistivity. The optimized design of CS-TOPCon solar cell results in achieving up to 29.03% due to high electric field.

Reduction in parasitic capacitance and resistance in FinFET is quite necessary in order to achieve high performance. In this paper, an intensive study on structural advancement in three different ways is implemented in basic FinFET structure such as (a) addition of thin silicide layer as interfacial layer between the contact and source/drain (b) extended and elevated source/drain (c) addition of hybrid spacer. Additionally, comparative study on the analog and RF performance is performed and analyzed for this structure between single material gate (SMG) and tri material gate (TMG) FinFET with all above enhancements. The analog parameters that have been analyzed are transconductance $(\mathrm{g}_{m})$ , transconductance generation factor (TGF), output conductance $(\mathbf{g}_{d})$ , and intrinsic gain $((\mathbf{g}_{m}/(\mathbf{g}_{d})$ . Similarly, the RF parameters like gate capacitance $(\mathbf{C}_{GG})$ , cut off frequency $(\mathbf{f}_{t})$ , transconductance frequency product (TFP), gain frequency product (GFP), and gain transconductance frequency product (GTFP) are reported. Even though there is a degradation in the mobility for the TMG FinFET, but on a whole provides better performance. Furthermore, the effect of temperature on the drain current and transconductance has been shown for the TMG structure by varying the temperature from 200 to $350\mathbf{K}$ with intervals of $50\mathbf{K}$ which would be the extension to this paper. Analysis gives an potential overview on different structural improvement in order to achieve higher performance.

The influence of polarization charges on the performance of III-nitride multiple quantum well (MQW) based nanowire photovoltaic devices due to stress and strain at heterointerfaces is investigated. The 7 × GaN/In x Ga1‐ x N core/shell MQW triangular nanowire solar cell with {0001}, {1 $\bar{1}$ 0 $\bar{1}$ }, { $\bar{1}$ 10 $\bar{1}$ } or {000 $\bar{1}$ }, {1 $\bar{1}$ 01}, { $\bar{1}$ 101} set of facets is intensively studied by numerical calculations. It is observed that the behavior of QWs in different facets of nanowire solar cells possesses an irregular pattern due to a complex distribution of strain and stress parameters depending on crystallographic orientations. Finally, the effect of polarization charges on optical and electrical performance of the nanowire solar cell is investigated in detail. It reveals that QWs along {000 $\bar{1}$ } facet of the nanowire have a favorable influence on III-nitride nanowire photovoltaic devices. It is interesting to observe that a remarkable efficiency of ∼9.82% with 94.34% fill factor and more than 70% quantum efficiency is achieved from 7 × GaN/In0.1Ga0.9N MQWs sandwiched between n-GaN and p-GaN layer under 1 Sun AM1.5 illuminations.

In this study, the influence of spontaneous and piezo-phototronic effect on the performance of hexagonal and triangular III-Nitride nanowire (NW) photovoltaic devices are investigated. The effect of stress/strain distribution on band structure of GaN/InxGa1-xN/GaN core/shell/shell NW solar cell with hexagonal and triangular geometrical shape are also intensively investigated by numerical calculations. It is observed that NW solar cells possess a non-uniform pattern of polarisation charges (PCs) due to complex distribution of strain and stress parameters depending upon growth orientations of NWs. Effect of PCs, especially due to piezo-phototronic effect on the polar, semi-polar and non-polar planes of NW having Miller–Bravais indices of {000-1}, {1-101} and {1-100} are discussed in detail, respectively. This numerical study not only provides the basic theoretical understanding about the spontaneous and piezo-phototronic effect on III-Nitride solar cell but also assists to obtain most optimised geometrical design to achieve high performance NW solar cell.

Now a days solar photovoltaic (PV) is the promising technology to address global issues such as carbon-free electricity, shortage of fossil-fuel, global warming and low cost electricity. This would be successful while the conversion efficiency is improved and new technology is developed. One such technology to achieve over 40% efficiency is to stack III–V compound semiconductors to form multi-junctions. Indium Gallium Nitride (InxGa1−xN) is a highly emerging material with band gap ranging from 0.64 to 3.4 eV which has the ability to absorb nearly whole solar spectrum to increase the conversion efficiency copiously. Since past few years, In x Ga1−x N material has been showing its potential for different optoelectronic and power electronic applications. This motivation is driving immense scientific interest to develop high-performance solar cells using In x Ga1−x N material. This paper highlights the basic advantageous properties of In x Ga1−x N materials, its growth technology and state-of-the-art application towards PV devices. The most important challenges that remain in realizing a high-efficiency In x Ga1−x N PV device are also discussed here. Finally, conclusions are drawn about the potential and future aspects of In x Ga1−x N material system towards terrestrial as well as space photovoltaic applications.

Now-a-days III-Nitride nanowires with axial (nanodisk) and radial (core/shell/shell-nanowire) junctions are two unique and potential methods for solar energy harvesting adopted by worldwide researchers. In this paper, polarization behavior of GaN/InGaN/GaN junction and its effect on carrier dynamics of nanodisk and CSS-nanowire type solar cells are intensively studied and compared with its planar counterpart by numerical simulations using commercially available Victory TCAD. It is observed that CSS-NW with hexagonal geometrical shapes are robust to detrimental impact of polarization charges and could be good enough to accelerate carrier collection efficiency as compared to nanodisk and planar solar cells. This numerical study provides an innovative aspect of fundamental device physics with respect to polarization charges in CSS-NW and nanodisk type junction towards photovoltaic applications. The internal quantum efficiencies (IQE) are also discussed to evaluate carrier collection mechanisms and recombination losses in each type of junctions of solar cell. Finally, it is interesting to observe a maximum conversion efficiency of 6.46% with 91.6% fill factor from n-GaN/i-In 0.1 Ga 0.9 N/p-GaN CSS-nanowire solar cell with an optimized thickness of 180 nm InGaN layer under one Sun AM1.5 illumination.

In III–nitride nanowire (NW)-based solar cells, efficient utilization of polarization charges is essential in order to achieve high performance. In this paper, the polarization behavior of a GaN/In x Ga1– x N/GaN core/shell/shell triangular NW solar cell with {000-1} or {0001} as one of the facets is intensively studied through numerical simulations. An analysis of defect density, strain profile, and polarization charges at different facets of NWs with different “In” compositions is considered carefully. It is observed that an NW solar cell with a N-polar {000-1} facet is good enough to enhance carrier collection efficiency as compared with Ga-polar {0001} facet. This numerical study provides an innovative aspect of implementation of fundamental device physics with respect to recent growth techniques in order to realize the application of III–nitride NWs toward photovoltaic applications. The effect of an In x Ga1– x N layer with different “In” compositions in all crystallographic orientations of NW solar cells is also discussed. It is interesting to observe that a maximum conversion efficiency of ~3.85% with the 93.38% fill factor is achieved from an n-GaN/i-In x Ga1– x N/p-GaN nanowire solar cell considering 10% of “In” content under one Sun AM1.5 illumination.

In this paper, a detailed comparative study of RF and analog performance of FinFET structure is reported for two different gate dielectric materials - SiO 2 and HfO 2 . Initially, the comparison of transfer characteristics of FinFET for both SiO 2 and HfO 2 is shown. The various analog parameters like transconductance (g m ), transconductance generation factor (TGF), output conductance (g d ), and intrinsic gain (g m /g d ) are also reported for both the gate dielectric materials. Likewise, a comparative analysis of various RF parameters such as gate capacitance (CGG), cut-off frequency (ft), transconductance frequency product (TFP), gain frequency product (GFP) and gain transconductance frequency product (GTFP) are reported between SiO 2 and HfO 2 . It is visualized that HfO 2 -based gate dielectric device provides better analog performance, whereas, the device with SiO 2 as gate dielectric shows improved RF parameters

This paper presents the design and analysis of a cost-efficient multi-junction tandem solar cell based on III-nitride alloys. In this work, band engineering between InGaN & Si layers is proposed to eliminate additional tunnel junction in between top and bottom cell, which will reduce the cost as well as enhance the performance of a solar cell. The self-tunneling effect of hetero junction is investigated using energy band diagram and the performance of solar cell is analyzed by extracting electric field intensity and current-voltage curves. Additionally, optimization of the Indium concentration and its consequent analysis are carried out to achieve high efficiency. The design of proposed solar cell is designed and simulated using TCAD tool. The multi junction solar cell achieved an open circuit voltage (Voc) of 2.09 V and short circuit current (Jsc) of 1.37 mA/cm2 with 86.7% fill factor (FF). The proposed device may replace traditional multi junction solar cell with tunnel junction for high efficiency applications.

Background Oral squamous cell carcinoma (OSCC) is the most common malignancy, representing up to 80% to 90% of all malignant neoplasms of the oral cavity. The role of microbes in association with the host is known to promote cancer progression, which is considered a prominent risk factor for oral OSCC. In view of a recent systematic review on microbial involvement, a proficient conclusion was derived associating microbes in OSCC progression. Objective Identification of most relevant microbial species associated in OSCC progression using statistical meta-analysis. Methods A preliminary search was primed through different literature databases including PubMed, Embase, and Cochrane for a systematic review by using different MeSH terminologies for microbial association with OSCC progression. A meta-analysis was done to identify statistically significant bacterial species. Results Results of this analysis presented the forest plots with statistically evaluated odds ratios and confidence intervals for each considered bacterial concentration. According to the results, no single or clustered microbial entity evaluated could confirm its significant association with OSCC progression. This could be because of a lack of qualitative and quantitative data and needs extensive evaluation using throughput research techniques. Conclusions The observations of the bacterial risk factors of OSCC through meta-analysis have been concluded with the identification of statistically insignificant association of microbes with OSCC progression. But, among those possibly consistent species, Prevotella melaninogenica might play a sensitive role in propagating OSCC progression.

Interactions involving host plants (cowpea, groundnut, cotton, sunflower, greengram, blackgram) an insect herbivore, black legume aphid Aphis craccivora Koch (Hemiptera: Aphididae) and a predator, the zigzag beetle Cheilomenes sexmaculata (Fabricius) (Coleoptera: Coccinellidae) were investigated during 2014-2015. The preference of the aphid A. craccivora for host plants measured in terms of growth and multiplication was cowpea > groundnut > greengram > blackgram > sunflower > cotton (most preferred to least preferred). Cowpea was the most preferred host plant for growth and multiplication of A. craccivora. Aphid's oviposition period was longest, fecundity greatest; adult longevity longest (188.40 ± 28.87 h; 52.00 ± 10.92; 231.60 ± 40.41 h), and nymphal mortality was lowest (0%) when reared on cowpea followed by groundnut, greengram and blackgram. Aphids had highest nymphal mortality (100%), with very few or no live adults produced, when reared on sunflower and cotton, the least preferred host of A. craccivora in this study. At the third trophic level, both the larvae and the adults of the coccinellid, Cheilomenes sexmaculata, consumed more of the aphids reared on groundnut than of those reared on blackgram, greengram, cowpea, sunflower and cotton. The biochemical constituents (phenols) present in cotton and sunflower, which contributed to the aphid's nymphal mortality, also affected the feeding behaviour of the coccinellid.

Single Event Transients (SET’s) occur in analog integrated circuits due to the strike of a heavy-ion (or) heavy energy proton at the transistor junction. It produces electron–hole pairs, which propagates in the circuit and results in amplitude variation, phase displacement at the output voltage. This paper presents a Radiation Hardened By Design (RHBD) current starved inverter buffer Voltage Control Oscillator (VCO) for the application of Phase Locked Loop (PLL). The proposed VCO is composed of current starved inverter delay VCO and majority voter. The current starved inverter delay VCO is designed with the inverter delay cell, and a single current source is shared for each delay cell. The majority voter is designed by Gate Diffusion Input (GDI) logic to reduce power consumption. The Linear Energy Transfer (LET) ranging from 14.47 to 100 Mev − cm 2 ∕ mg is applied at the nodes of VCO. The proposed mitigation technique reduces the SET effect by 98%, and it operates at the frequency range from 0.5 GHz to 2.5 GHz with the power consumption of 290 μ W.

In this work, the carrier confinement mechanism through nanostructures is studied in a copper-zinc-tin-sulfide/Cu2ZnSnSe4-type kesterite material, resulting in a remarkable performance enhancement of solar cells. The effect of the quantized energy band, recombination rate, and escape mechanism on the spectral response of solar cells is explored in detail. The mathematical model for carrier dynamics and performance measuring parameters are analyzed and optimized. Moreover, the number of quantum wells is incorporated gradually up to 100 and the corresponding performances are explored. It is observed that with the increase in the number of wells, photogenerated current density enhances significantly up to a saturation point and then deteriorates. A remarkable efficiency of 24.8% and more than 80% of quantum efficiency are achieved from 50 numbers of quantum wells with 79.8% of fill factor.

In this paper, we present a new Z-shaped line tunnel field effect transistor (TFET) employing drain doping engineering with a split drain structure (SD-ZHP-TFET). The split drain (SD) approach in the proposed ZHP-TFET helps increasing tunneling width at the channel-drain interface, reducing ambipolarity. Moreover, a horizontal pocket (HP) is implanted in the source region to boost the ON-current of the proposed SD-ZHP-TFET structure. The effect of both these approaches in the line-TFET provides higher ON-current and reduces ambipolarity significantly. Split drain structure in the ZHP-TFET exhibits a three-decade improvement in the ambipolar current without affecting the subthreshold (SS) and leakage current significantly. A calibrated simulation study of split drain thickness (tu) and drain region doping variation on the analog performance are investigated using the technology computer-aided design device simulator. Moreover, the high-frequency figure of merit regarding total gate capacitance (Cgg), unit-gain cut-off frequency (fT) is analysed. It is found that the drain doping improves the cut-off frequency from 1.8 GHz in ZHP-TFET to 2.2 GHz in the proposed SD-ZHP-TFET structure. Thus the proposed device is capable of providing higher ION/IOFF (≈1013) and ION/IAMB (≈1013) ratio with an average SS of 44 mV/decade.