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In this present paper, we studied about the dependance of capacitance of coupled stripline on strip width, frequency and spacing between two striplines. Miniaturized microwave circuits fabricated by extension of integrated circuits (ICs) technology to microwave frequencies are known as Microwave Integrated Circuits (MICs). MICs promise a real revolution leading to both expansion of present markets of microwaves & opening of many new applications including host of non-military uses in India & abroad. With the advent of MICs planar Transmission Lines have been developed which have been proved to be very significant as regards the fabrication of various microwave-components such as: Directional Coupler, Filters, Isolator & Impedance transformers etc. The planar Transmission Lines are: Stripline, Microstripline, Slot line, Coplanar Striplines & their different variant forms such as inverted and suspended striplines & microstriplines etc. Among these microstripline is the most suited due to its open structure, low losses in gigaharz range of frequency, reduced size, improved reliability and eventual cost reduction in mass production. The microstrip transmission line consists of a narrow strip conductor separated from a conducting ground plane by an intervening supporting dielectric substrate as studied by Wheeler and others. The electromagnetic traveling through such structures suffers from some losses like: Conductor loss & Dielectric loss. There is a change of phase of the wave traveling through the structure also. This phase change (shift) depends on the width of metal strip, height of the dielectric substrate, permittivity of the substrate and operating frequency. The present study is devoted to this objective i.e. we have to study the variation of Phase-Shift of the wave within the structure with width of the stripline, height & effective permittivity of the structure & frequency.

The utility of groundwater, irrespective of its availability, is essential for mankind. The efficacy of the coastal aquifer’s groundwater quality for agriculture purpose in the Pondicherry region was gauged by their hydrochemistry. 44 groundwater samples were collected during 4 different seasons namely, pre-monsoon (PRM), southwest monsoon (SWM), northeast monsoon (NEM) and post-monsoon (POM). The samples were measured for physico-chemical parameters like pH, EC, TDS, Na, K, Ca, Mg, Cl, HCO3, PO4, SO4 and NO3. The spatio temporal variations of EC indicates that the coastal groundwater were relatively saline except during PRM. The suitability of groundwater for irrigation is evaluated through various water quality parametrs such as Electrical Conductivity (EC), pH, Na%, sodium absorption ratio (SAR), residual sodium carbonate (RSC) and permeability index (PI). Na%, SAR, PI and EC values were spatially interporlated and integrated to determine the regions suitable for irrigation purpose. The study infers that the groundwater of the study area is suitable for irrigation except few samples’ locations along the western part, as they have attained an alarming stage and they are unsuitable for irrigation. Thus, proper management strategy for irrigation water source has to be developed and a preventive management practice to address this issue has to be implemented.

With electron filling n = 1 in the Sr 2 VO 4 compound, the octahedrally coordinated t 2 g orbitals are strongly active when the tetragonal distortion induced crystal field is tuned by external agent such as pressure. Considering the full range of crystal field induced tetragonal splitting in a realistic three-orbital model, collective spin–orbital excitations are investigated using the generalized self-consistent plus fluctuation approach. At ambient pressure, an entangled orbital + antiferromagnetic order is found to be stabilized beyond a critical value (∼30 meV) of spin–orbit coupling which is in the realistic range for 3d ions. The behavior of the calculated energy scales of collective excitations with crystal field is consistent with that of the transition temperatures with pressure as obtained from susceptibility and resistivity anomalies in high-pressure studies.

In the multiband systems, Hund's coupling ($J$) plays a significant role in the spin and charge excitations. We study the dependence of electronic anisotropy on $J$ in terms of Drude-weight along different directions as well as the orbital order in the four-fold symmetry broken spin-density wave state of iron pnictides. A robust behavior of the Drude-weight anisotropy within a small window around $J \sim 0.25U$ with $U$ as intraorbital Coulomb interaction is described in terms of orbital-weight distribution along the reconstructed Fermi surfaces. We also find that the ferro-orbital order increases with $J$ in the widely accepted regime for the latter, which is explained as a consequence of rising exchange field with an increase in magnetization., 6 pages, 3 figures

Viologen based covalent organic polymer (COP) interfaced with graphene at the nanoscale showed pseudocapacitive energy storage associated with redox-active moieties. The positively charged viologen moieties endow charge storage as well as easy wetting of the electrode. The non-conducting COP grown over conducting graphene enhances its performance by extensive interface formation. All the redox states of viologen moieties can be reversibly attained without significant polarization when it is interfaced with graphene. However, the COP (devoid of graphene) shows irreversible/pseudo-reversible behavior due to lack of electron conducting pathways. The intimate and dense conducting pathways in graphene-COP composites facilitates the charge transfer across interface leading to effective and reversible participation of redox moieties across the entire range over 1000 cycles. Also, we show that the strategy being universal in nature and aid in electron transfer in dense 3D networks which lacks traditional pi-pi stacking of 2D crystalline networks (COF).

Chronic Kidney Disease (CKD) is one of worldwide medical challenges with high morbidity and death rate. Since there is no symptom during the early stages of CKD, patients often fail to diagnose the disease. Patients with HIV have more chances to be affected with CKD in critical condition. Early detection of CKD helps patients to obtain prompt care ald delays the further progression of disease. With the availability of pathology data, the use of machine-learning techniques in healthcare for classification and prediction of disease has become more common. This paper presents the classification of CKD using machine learning models. Based on the glomerular filtration rate, the CKD stages are also calculated for patients diagnosed with CKD. DNN model outperforms with 99% of accuracy in classifying CKD patients with HIV.

In recent years, transfer learning has gained huge popularity in solving problems from various fields including the medical image analysis. Clinical picture examination has altered medical services in the course of recent years, permitting specialists to discover disease earlier and improve patient recovery. Imaging has assumed a significant role in the finding of Alzheimer disease (AD). AD is a progressive neurological issue that gradually destroy memory and thinking skills of human. Initially, Computed Tomography scan (CT) and then Magnetic Resonance Imaging (MRI) were utilized to discover reasons of dementia in AD patients. This research aims to classify MRI of Alzheimer disease patients into multiple class by using VGG16, ResNet -50 and AlexNet as transfer learning models along with convolution neural networks. There are some stages of AD like mild cognitive impairment, mild Alzheimer’s, moderate Alzheimer’s and severe impairment. The proposed strategies show results with an accuracy of 95.70%, this represents a substantial improvement in accuracy over previous studies, demonstrating the efficacy of the proposed method.

We investigate the magnetic excitations in view of the recent reports suggesting that the spin-wave energy may exhibit a significant dependence on the in-plane strain of a thin film of La$_2$CuO$_4$. The nature of dependence, as we find, can be explained naturally within a two-orbital model based on the $d_{x^2-y^2}$ and $d_{3z^2-r^2}$ orbitals. In particular, as the orbital-splitting energy between the $d_{x^2-y^2}$ and $d_{3z^2-r^2}$ orbitals increases with compressive strain, the zone-boundary spin-wave energy hardens. However, the hardening persists only until the orbital splitting reaches $\sim$ 2eV, beyond which there is no significant change. The behavior of zone-boundary spin-wave energy is explained in terms of the extent of hybridization between one of the exchange-split $d_{x^2-y^2}$ band which is nearly half filled and the $d_{3z^2-r^2}$ band. The role of second-order antiferromagnetic superexchange process involving the inter-orbital hopping is also discussed., 6 pages, 5 figures

We show conclusively that a pseudogap state can arise at $T > T_c$, for reasonable pairing interaction strength, from order parameter fluctuations in a two dimensional minimal model of $d$-wave superconductivity. The occurrence of the pseudogap requires neither strong correlation nor the presence of competing order. We study a model with attractive nearest neighbor interaction and establish our result using a combination of cluster based Monte Carlo for the order parameter field and a twisted-boundary scheme to compute the momentum-resolved spectral function. Apart from a dip in the density of states that characterizes the pseudogap, the momentum and frequency resolution on our effective lattice size $\sim 160 \times 160$ allows two major conclusions: (i)~at $T < T_c$, despite the presence of thermal phase fluctuations the superconductor has only nodal Fermi points while all non nodal points on the normal state Fermi surface show a two peak spectral function with a dip at $��=0$, and (ii)~for $T > T_c$ the Fermi points develops into arcs, characterized by a single quasiparticle peak, and the arcs connect up to recover the normal state Fermi surface at a temperature $T^* > T_c$. We show the variation of $T_c$ and $T^*$ with coupling strength and provide detailed spectral results at a coupling where $T^* \sim 1.5T_c$., 7 pages, 6 figures

Mass transport and charge transfer at an interface play a crucial role in governing the electrochemical performance of a material. Wider meso-/macropores are expected to enhance the reaction kineti...

A new porphyrin-based compound, Zn-3(C40H24N8)(C20H8N2O4)(2)(DEF)(2)](DEF)(3) (1; DEF =N,N-diethyl-formamide), has been synthesized by employing 5,10,15,20-tetrakis(4-pyridyl)porphyrin, 1,2-diamino-3,6-bis(4-carboxyphenyl)benzene, and Zn2+ salt at 100 degrees C under solvothermal conditions. The structure, as determined by single-crystal XRD studies, is three-dimensional with threefold interpenetration. The usefulness of free -NH2 groups in the ligand was exploited for anchoring silver nanoparticles through a simple solution-based route. The silver-loaded sample, Ag@1, was characterized by powder XRD, energy-dispersive X-ray spectroscopy, high-resolution TEM, SEM, X-ray photo-electron spectroscopy, and inductively coupled plasma MS analysis, which clearly indicated that silver nanoparticles with a size of 3.83 nm were uniformly distributed within the metal-organic framework (MOF). The Ag@1 sample was evaluated for possible catalytic activity for the carboxylation of a terminal alkyne by employing CO2 under atmospheric pressure; this gave excellent results. The Ag@1 catalyst was found to be robust, active, and recyclable. The present studies suggest that porphyrin MOFs not only exhibit interesting structures, but also show good heterogeneous catalytic activity towards the fixation of CO2.

We investigate quasiparticle interference in the coexistence phase of spin-density wave state and s -wave superconductivity using a five-orbital tight-binding model. We examine underdoped and overdoped cases, one with magnetic-exchange gap significantly larger than the superconducting gap, and other with both gaps being comparable. In the former case, QPI peaks are very weak or absent near ( 0 , ± π ) for either of the states with s +− - or s ++ -wave symmetry while they are present near ( ± π , 0 ) in each case, thus making any differentiation between them difficult. In the latter case, a clear distinction between the two types of states is obtained as the peaks are intense near ( 0 , ± π ) and ( ± π , 0 ) for the s +− - and s ++ -wave symmetry, respectively.

We present a simple route to synthesize of porous bi-metallic phosphides with large surface area supporting high density of electrochemically active sites, and demonstrate that resulting Ni0.2Co0.8P exhibits outstanding performance in catalysing oxygen evolution reaction (OER) under alkaline condition. It requires a very low over potential of 230 mV to achieve an anodic current density of 10 mA cm−2 with a Tafel slope of 44 mV dec−1. Ni0.2Co0.8P is also shown to perform well in catalyzing hydrogen evolution reaction (HER) under both alkaline (0.1 M KOH solution) and acidic conditions (0.5 M H2SO4 solution). Through first-principles theoretical analysis, we show that such high catalytic activity arises from the synergistic effect of Ni and Co on energies of d and p bands of Ni0.2Co0.8P, which is further enhanced by rapid mass transport possible due to the porous architecture of its three-dimensional network morphology.

The prevalence of obesity and overweight has risen to such an extent that it has become a matter of concern. Gymnema sylvestre is popular in indigenous system of medicine. Present study was planned to explore the antiobesity property of extract of leaves of Gymnema sylvestre in rat model of obesity. Adult wistar rats weighing around 150-200g were used. Obesity was induced by feeding with high fat diet (HFD) for four weeks. Gymnema sylvestre leaves extract was used in a dose of 100mg/kg and 200mg/kg. Body weights, body mass index, locomotor activities (ambulatory activity and frequency of rearing) were recorded. At the end of 8th week rats were sacrificed, their internal organs (kidney, liver, spleen and heart) and fat pads (perirenal, mesenteric and gonadal) were identified, removed and weighed. On giving test drug all the parameters of obesity improved significantly. GS 100 mg/kg caused around 33% weight reduction while GS 200mg/kg caused around 38% weight reduction when compared to the disease control group. Significant improvement was also observed for BMI and locomotor activities. Weight of internal organs and fat pads also decreased significantly as compared to the disease control group. Present study concludes that leaf extract of Gymnema sylvestre possess significant dose dependent antiobesity activity. The drug acts in a dose dependent manner with 200 mg/kg being more effective than 100mg/kg.

Sodium cobalt metaphosphate [NaCo(PO3 )3 ] has CoO octahedra (CoO6 ) and shows superior oxygen evolution reaction (OER) activity in alkaline solution, comparable with the state-of-the-art precious-metal RuO2 catalyst. OER catalysts of this metaphosphate are prepared by combustion (Cb) and solid-state (SS) methods. The combustion-assisted method offers a facile synthesis and one-step carbon composite formation. Unusually high catalytic activity was observed in NCoM-Cb-Ar and could be due to chemical coupling effects between NaCo(PO3 )3 and partially graphitized carbon. This novel electrocatalyst exhibits very small overpotential of 340 mV with high mass activity of 532 A g-1 . Good charge transfer abilities and chemical coupling between NaCo(PO3 )3 and amorphous carbon gives the OER activity in NCoM-Cb-Ar.

An efficient, N-doped, pore-engineered carbon as a dual electrocatalyst for hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) is developed with the potential to replace traditional precious metal (Pt)-based catalysts. Rationally designed, N-doped carbons (NDCs) with wider mesopores (15–27 nm) exhibiting superior mass transfer properties were obtained following pyrolysis and demineralization of polydopamine-coated halloysite clay nanotubes. NDCs thus obtained exhibit excellent electrocatalytic activity for hydrogen evolution reaction (HER) with a lower onset potential (117 mV), smaller Tafel slope (94 mV dec−1) and high exchange current density (jo = 1.5 × 10−2 mA cm−2), which is comparable and even superior to other multiple heteroatom-doped carbons and transition metal chalcogenide/oxide-based systems reported previously. Furthermore, NDCs participate in an efficient, direct four-electron pathway for the reduction of molecular oxygen to water. The observed bifunctional electrocatalytic activity of the NDC can be attributed to the synergistic effect of enhanced mass transfer and efficient charge transfer processes at the electrodes and hence deems fit to be a promising candidate for future renewable energy blueprints viz. metal–air batteries and regenerative fuel cell technology.

Facile and efficient ball milling and polyol methods were employed for the synthesis of nickel selenide (NiSe) nanoparticle. The particle size of the NiSe nanoparticle has been controlled mechanically by varying the ball size in the milling process. The role of the surfactants in the formation of various morphologies was studied. The compounds were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray energy dispersive spectroscopy (EDS). The efficiency of the NiSe nanoparticle as a catalyst was tested for the reduction of para-nitroaniline (PNA) to para-phenyldiamine (PPD) and para-nitrophenol (PNP) to para-aminophenol (PAP) using NaBH 4 as the reducing agent. Particle size, morphology and the presence of surfactant played a crucial role in the reduction process.

Pulse detonation engines are the modern propulsive device which provides high thrust. They are unsteady propulsive devices which has multi cycle operations in it. In this multi cycle process for every cycle fuel and air are initiated and a shock wave is generated in combustion chamber in form of deflagration. Combustion chamber is maintained with high pressure and high temperature which leads to combustion of reactants. This deflagration transmits to detonation with high velocity and increasing Mach number. Deflagration propagates forward by taking all unburned species and products formed after combustion. Propagation of Deflagration – Detonation Transition (DDT) shock wave studies is a pioneering research concept. In the present study, simulation of PDE with Shchelkin spiral geometry is considered with two mass flow inlets has been used in which one is for fuel inlet and other for oxidizer. Geometry and meshing has been done in Gambit. Fuel used is gaseous fuel hydrogen and oxidizer is air mixture of O2, N2 work has been performed for different mass flow rates of fuel and oxidizer. Energy equation, Species transport equation to be solved in Fluent. Comparison results of DDT in parameters of mach number, velocity, pressure and temperatures depending on different time steps have been observed

Background: Objective of the study was to identify whether there is any benefit of integrating dry lab/computer assisted lab (CAL) tool with conventional teaching/wet lab in experimental part of pharmacology.Methods: A questionnaire based study was conducted among 158 second year medical undergraduates in the department of pharmacology. The questionnaire was distributed among students with proper prior instructions in practical class. Students willing to participate in the study were included.Results: Total 94.9% were in the favour of replacing conventional teaching with CAL lab learning, 74.7% felt conventional lab to be more complex, 92.4% has the opinion of CAL lab result has less error along with that majority student felt it to be less time consuming, need lesser assistance and enhance learning. 67% student also felt real experimentation can’t be learned by CAL tool and 83.5% have their thought that CAL lab can never help them in exercising real experiment.Conclusions: Although there is no substitution of conventional teaching methods, in this new era of information and technology CAL lab can be the saviour to students in making better understanding and enhancing the performance without help of experimental animals.

Objective: To explore the prevalence of self-medication among Second year MBBS graduates and to find out important determinant promoting such practices. Methods: A questionnaire-based study was done by including Second year undergraduates in the study. Study was done in a single sitting. Results: Majority of the students were practicing self-medication. Out of which previous prescriptions and family and friends found to be the major determinants influencing the practice of self-medication. it was also found majority are taking self-medication for fever and cough and cold. Also, the minority group not taking self-medication out of the risk of taking wrong drug. Conclusion: Self-medication is very common among medical undergraduates which can only be prevented by implementing strict rule against the pharmaceutical companies and by increasing awareness of adverse effects and drug resistance.

Impurity scattering is found to lead to quasi-one-dimensional nanoscale modulation of the local density of states in iron pnictides and chalcogenides. This ``quasiparticle interference'' feature is remarkably similar across a wide variety of pnictide and chalcogenide phases, suggesting a common origin. We show that a unified understanding of the experiments can be obtained by simply invoking a fourfold symmetry breaking ${d}_{xz}\text{\ensuremath{-}}{d}_{yz}$ orbital splitting, of a magnitude already suggested by the experiments. This can explain the one-dimensional characteristics in the local density of states observed in the orthorhombic nematic, tetragonal paramagnetic, as well as the spin-density-wave and superconducting states in these materials.

We explore the anisotropy in low frequency conductivity as a function of hole doping in multiorbital models of pnictides by analyzing the Drude weight in the $x$ and $y$ directions of a ($\pi$, 0) spin-density wave state. A reduction in the conductivity anisotropy with increased hole doping, and subsequent sign reversal, both observed in experiments, is found to be a common trend in these models. This behavior arises due to the interplay of low energy orbitally-resolved density of states and the geometrical features of the Fermi surface. An understanding of anisotropy in the electron doped regime, however, would require additional ingredients., Comment: 8 pages, 10 figures (To appear in PRB)

A new porphyrin-based compound, [Zn

According to World Health Organization report the number of deaths by road traffic accident is more than 1.25 million people and every year with non-fatal accidents affecting more than 20–50 million people. Several factors are contributed on the occurrence of road traffic accident. In this study, data mining classification techniques applied to establish models (classifiers) to identify accident factors and to predict traffic accident severity using previously recorded traffic data. Using WEKA (Waikato Environment for Knowledge Analysis) data mining decision tree (J48, ID3 and CART) and Naive Bayes classifiers are built to model the severity of injury. The classification performance of all these algorithms is compared based on their results. The experimental result shows that the accuracy of J48 classifier is higher than others.