Vertex-Fed Hexagonal Antenna with Low Cross-Polarization Levels

Probe-fed hexagonal patch antenna suffers from impedance mismatch especially when feed is located at one of the vertices of polygon. Hexagonal planar antennas also suffer from high cross polar levels. This paper proposes a method to overcome impedance mismatch and to increase co-polarization level by reducing ground plane. Vertex feeding is demonstrated in this paper to establish improvement in impedance values more clearly. The impedance at any vertex of a hexagonal patch is too high when compared to the characteristic impedance of the probe. Three vertex-fed hexagonal antennas are developed to demonstrate the effect of ground plane reduction within C-Band. The proposed technique can be optimized to match the impedance and achieve good return loss where monopole radiation characteristics are not an issue. A vertex-fed reduced ground hexagonal antenna is proposed here that operates around 5 GHz with a frequency span of 600 MHz. Thus, the proposed antenna is quite suitable for indoor wireless LAN (UNII-1) applications

Probe-Fed Polygonal Patch UWB Antennas

The chapter deals with the design of probe-fed planar antennas to operate at wider bands and techniques to improve peak or boresight gain using reflectors. The phenomenon of frequency excitation in dual-band, that is, C-band and X-band using the technique of partial removal of the ground plane, is well demonstrated here. The impedance bandwidth achieved by the sample antenna is 285 MHz and 380 MHz, respectively. The reduced ground plane technique is further exploited along with modifications in the shape of the ground plane to cover the entire ultra-wideband (UWB) range in a probe-fed hexagonal monopole antenna. Due to the existence of higher modes and especially when fed with a probe, UWB antennas are only capable of providing mediocre gain at higher frequencies. An approach to increase the probe-fed hexagonal UWB antenna’s peak gain involves the utilization of an appropriate reflector. The antenna is given an artificial magnetic conductor (AMC)-based reflector, which increases the peak gain as well as boresight gain across a band ≤ UWB. Peak and boresight gains of 3.74 dB and 5.5 dB, respectively, are observed with AMC. The equivalent circuit model and simulated impedance results of the sample antennas are validated with the measurement results

Alcoholism with central pontine demyelination: a case report

Central pontine myelinolysis is a non-inflammatory demyelinating disease characterized by loss of myelin with relative neuron sparing, associated with rapid correction of hyponatremia and sometimes hypernatremia or chronic alcoholism. We are reporting a case of 52 year old male patient who was chronic alcoholic from past 20 years, presented to us with complaints of altered sensorium and dysarthria of 5 days duration .He was investigated and diagnosed as case of central pontine myelinosis associated with chronic alcoholism

SPARSH: a camp based approach for orthopaedic disabilities and its success in central India

Background: Around 15% of population in the world is living with disability. The present study was carried out during the special project for assistance, rehabilitation and strengthening of handicapped (SPARSH) camp to know the current pattern of locomotor disability and to observe the outcome of the camp surgeries for the correction of deformity.Methods: This prospective observational cross-sectional study was conducted at the department of orthopaedics and traumatology Gandhi Medical College at SPARSH camp organised by the Government of M. P. at J. K. hospital Bhopal. All the patients with locomotor disability attending the SPARSH camp irrespective of age, sex and cause, were included in the studyResults: In total 287 patients attended the camp in which majority of the patients were suffering from cerebral palsy. 107 patients were selected for operative intervention in which tendo-achilles lengthening was performed most commonly.Conclusions: The corrective surgical camp provides an avenue of healthcare opportunity for the underprivileged sector of society. A camp based approach helps in identification, gradation & rehabilitation of orthopaedic deformities

Study of Microstrip filters

Volume 2 Issue 1 (January 2014

Linkages between oral commensal bacteria and atherosclerotic plaques in coronary artery disease patients

Coronary artery disease is an inflammatory disorder characterized by narrowing of coronary arteries due to atherosclerotic plaque formation. To date, the accumulated epidemiological evidence supports an association between oral bacterial diseases and coronary artery disease, but has failed to prove a causal link between the two. Due to the recent surge in microbial identification and analyses techniques, a number of bacteria have been independently found in atherosclerotic plaque samples from coronary artery disease patients. In this study, we present meta-analysis from published studies that have independently investigated the presence of bacteria within atherosclerotic plaque samples in coronary artery disease patients. Data were collated from 63 studies covering 1791 patients spread over a decade. Our analysis confirms the presence of 23 oral commensal bacteria, either individually or in co-existence, within atherosclerotic plaques in patients undergoing carotid endarterectomy, catheter-based atherectomy, or similar procedures. Of these 23 bacteria, 5 (Campylobacter rectus, Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, Prevotella nigrescens) are unique to coronary plaques, while the other 18 are additionally present in non-cardiac organs, and associate with over 30 non-cardiac disorders. We have cataloged the wide spectrum of proteins secreted by above atherosclerotic plaque-associated bacteria, and discuss their possible roles during microbial migration via the bloodstream. We also highlight the prevalence of specific poly-microbial communities within atherosclerotic plaques. This work provides a resource whose immediate implication is the necessity to systematically catalog landscapes of atherosclerotic plaque-associated oral commensal bacteria in human patient populations

Fabrication of Variable Morphologies on Argon Sputtered PMMA Surfaces

Ion beam induced patterning and fabrication of various topographies over polymeric surfaces has drawn strong interest due to latent applications in photonics, magnetic devices, optical devices and photovoltaics etc. In this work, we report the controlled surface structuring and evolution of different morphologies in Poly(methyl methacrylate) polymer using Ar+ ion beam fabrication technique. Morphological and structural analysis has been performed by ex situ Atomic Force Microscopy (AFM) and X-ray Diffraction. The effect of oblique incidences on argon sputtered films was evaluated by various surface topography and texture parameters, such as Fast Fourier Transforms, surface roughness, skewness, kurtosis. AFM study demonstrates fabrication of transient morphologies over argon sputtered surfaces. One dimensional (1D) cross section scans of surface profiles are determined and morphological features are investigated. The results showed halo peaks in the XRD patterns, which indicate the amorphous nature of this type of polymer. The formation of these surface structures is attributed to the different degree of sputtering yield at different off-normal incidences and preferential sputtering of hydrogen in comparison to carbon in ion sputtered surfaces

A PORTRAYAL OF THE SOCIODEMOGRAPHICS AND OPTIMAL UPTAKE OF ANTENATALCARE SERVICES AMONG PREGNANT WOMEN OF URBAN SLUMS IN INDIA: AN INITIAL DATASET DEPICTION

Escalating deployment of maternal healthcare services has considerably impacted maternal mortality rates. However, urban slums have remained an understudied area in this context. Aim: To assess maternal healthcare service utilization patterns and influencing factors during antenatal period in urban slums. The analysis encompasses Fertility, Family Planning Practices, Dietary Habits, Health Quality, and implications of COVID-19 on Pregnancy. Method: Cross-sectional research conducted between April and June 2022, among urban slums in South Delhi, targeting pregnant women aged 18-44 years. Data from 250 ongoing pregnancies, accessed through Aganwadi centers, were collected electronically following study porotocol. Result: Results indicated that 98% of participants were under 40 years of age, with 67% falling below 28 years. About 93% of sample population was educated, with 93% as homemakers. Among women with parity, 82% had one child. Awareness of ANC was widespread, with 78% demonstrating medium level of knowledge. Media exposure and family planning adoption were minimal (47% and 51%, respectively). ANC utilization rates were high, with 98%, 97%, and 94% receiving iron and folic acid, tetanus toxoid, and ultrasound examinations, respectively. Only 2% were exposed to COVID-19 during pregnancy. Conclusion: This initial investigation indicates low media exposure and family planning adoption. However, ANC awareness and utilization were significant. Strategies should prioritize women's education to enhance awareness of ANC and postnatal care. Strengthening public health infrastructure is vital for optimizing maternal service utilization

Influence of Impurity on the Properties of Chemically Synthesized Calcium Hydroxide

Here we report synthesis and characterization of chemically synthesized calcium hydroxide (Ca(OH)2) with and without deliberate presence of NaNO3 as an impurity. Calcium nitrate tetrahydrate (Ca(NO3)2.4H2O) is used as precursor and alkaline NaOH solution is used as precipitant to synthesize the Ca(OH)2 samples. The samples were characterized by XRD, FESEM, FTIR spectroscopy, DTA, TGA and UV-Vis spectroscopy techniques. From the UV-Vis spectroscopy results, it is found that the Ca(OH)2 with NaNO3 impurity has higher bandgap than the sample without NaNO3. The weight loss in TGA is also more for the Ca(OH)2 with impurity than the one for without impurity. The results are discussed in terms of composition formed during synthesis process