TRIPLE-BAND STUB LOADED PATCH ANTENNA WITH HIGH GAIN FOR 5G SUB-6 GHZ, WLAN AND WIMAX APPLICATIONS USING DGS

Microstrip antennas have become ubiquitous in today's wireless communication world due to their low profile, low cost, and simplicity in fabricating on circuit boards. However, poor performance characteristics, such as limited bandwidth, low power handling capabilities, and low gain, limit their applicability in various instances. Path loss will be substantial in 5th generation (5G) wireless communication due to the utilization of high-frequency bands. A high-gain antenna with a small size is necessary to address this issue. A compact tri-band, slotted monopole antenna with high and consistent gain employing a defected ground plane structure (DGS) has been investigated and implemented in this study. This proposed antenna uses three inverted L-shaped stubs connected to the radiating element to cover the desired bands while keeping the antenna size small. The designed antenna has two key characteristics: (i) wide bandwidth and (ii) reasonable gain. The antenna covers 2.45 and 5.6 GHz WLAN, 2.4 GHz Wi-Fi, 2.5 and 5.2 GHz WiMAX and 3.7 GHz Sub-6 GHz of 5G for mobile communication. The overall substrate size of the antenna is 30 × 17 × 1.6 mm3and the electrical dimensions are 0.49 λL × 0.28 λL ×0.026 λL, where λL is the free space wavelength at 2.45 GHz. The measured reflection coefficient (S11 < -10dB) covers 2.4 - 2.52 GHz (bandwidth 112 MHz) and 3.4 - 4.1 GHz (bandwidth 700 MHz) and 5.2 - 6.6 GHz (bandwidth 1359 MHz) with a fractional bandwidth of 5.1 % at lower frequency band, 18.6 % at mid frequency band and 23.7 % at high frequency band. A prototype antenna has also been developed using an inexpensive, low-profile 1.6 mm thick FR-4 (εr = 4.4) substrate. The measured peak gains achieved are 1.35 dB at 2.45 GHz, 2.55 dB at 2.65 GHz and 3.8 dB at 5.5 GHz. The simulated results have been validated against actual experimental measurements, and the outcomes are consistent and match with certainty. The proposed antenna design is very compact and easy to fabricate due to the absence of vias

A computational model of ureteral peristalsis and an investigation into ureteral reflux.

The aim of this study is to create a computational model of the human ureteral system that accurately replicates the peristaltic movement of the ureter for a variety of physiological and pathological functions. The objectives of this research are met using our in-house fluid-structural dynamics code (CgLes-Y code). A realistic peristaltic motion of the ureter is modelled using a novel piecewise linear force model. The urodynamic responses are investigated under two conditions of a healthy and a depressed contraction force. A ureteral pressure during the contraction shows a very good agreement with corresponding clinical data. The results also show a dependency of the wall shear stresses on the contraction velocity and it confirms the presence of a high shear stress at the proximal part of the ureter. Additionally, it is shown that an inefficient lumen contraction can increase the possibility of a continuous reflux during the propagation of peristalsis

Numerical study of nonlinear heat transfer from a wavy surface to a high permeability medium with pseudo-spectral and smoothed particle methods

Motivated by petro-chemical geological systems, we consider the natural convection boundary layer flow from a vertical isothermal wavy surface adjacent to a saturated non-Darcian high permeability porous medium. High permeability is considered to represent geologically sparsely packed porous media. Both Darcian drag and Forchheimer inertial drag terms are included in the velocity boundary layer equation. A high permeability medium is considered. We employ a sinusoidal relation for the wavy surface. Using a set of transformations, the momentum and heat conservation equations are converted from an (x, y) coordinate system to an (x,η) dimensionless system. The two-point boundary value problem is then solved numerically with a pseudo-spectral method based on combining the Bellman–Kalaba quasi linearization method with the Chebyschev spectral collocation technique (SQLM). The SQLM computations are demonstrated to achieve excellent correlation with smoothed particle hydrodynamic (SPH) Lagrangian solutions. We study the effect of Darcy number (Da), Forchheimer number (Fs), amplitude wavelength (A) and Prandtl number (Pr) on the velocity and temperature distributions in the regime. Local Nusselt number is also computed for selected cases. The study finds important applications in petroleum engineering and also energy systems exploiting porous media and undulating (wavy) surface geometry. The SQLM algorithm is shown to be exceptionally robust and achieves fast convergence and excellent accuracy in nonlinear heat transfer simulations

Long-term trends of surface air temperature in India

Salient features of the long-term variation of surface air temperature for India as a whole and for different regions of the country have been presented. Temperature data at 73 fairly widespread stations, for the period 1901-1982. have been used in the study. Seasonal and annual temperature anomaly series have been obtained for the different regions. Such series have also been obtained for latitude- and longitude-wise classifications. The long-term variation in the temperature has been evaluated by linear trend. The results indicate a slight but definite warming trend in the mean annual Indian temperatures. This warming is found to be mainly contributed by the post-monsoon and winter seasons. West coast, interior peninsula, north central and north-east regions of the country have shown pronounced warming in the mean annual temperatures. The post-1940 cooling reported for the Northern Hemisphere is not conspicuous in the mean annual Indian temperature anomalie

A Study on Oral Mucosal Lesions in 3500 Patients with Dermatological Diseases in South India

Background: Oral mucosal lesions that are observed in the dermatological diseases are categorized under mucocutaneous conditions. The oral lesions in dermatological diseases may be the early aspects of the disease manifestation or the most significant clinical appearance or the only sign/and or symptom of such dermatological diseases and occasionally lesions occur simultaneously in the skin as well as mucous membrane. Aim: This present study attempts to find out the prevalence of oral mucosal lesions in patients with dermatological diseases. Subjects and Methods: The study includes 3500 patients who attended out‑patient Department of Dermatology. Patients with oral manifestation were subjected for clinical examination in the Department of Oral Pathology. Diagnostic procedures were performed to confirm the clinical oral diagnosis. The results of the study were analyzed by SPSS software version 19.0 (Armonk, NY) and presented as descriptive statistics. Correlation of oral manifestions with their respective dermatological disease was statistically analysed by Pearson’s correlation test.(P &lt; 0.05 were considered as statistically significant) Results: The prevalence rate of oral mucosal lesions in the present study was 1.8% (65/3500). The most frequent lesions observed were psoriasis 32.3% (21/65), lichen planus 18.4% (12/65), Stevens Johnson Syndrome 18.4% (12/65), pemphigus 10.7% (7/65), toxic epidermal necrolysis 4.6% (3/65), systemic lupus erythematosus 3% (2/65), discoid lupus  erythematosus 1.5% (1/65), pemphigoid 1.5% (1/65). Gender distribution in the study population was statistically significant (P &lt; 0.001). Employed and unemployed individuals in the study population were statistically significant (P &lt; 0.001). Pearson’s correlation analysis of oral manifestations with their respective dermatological disease showed r = 0.466 and signifies a positive correlation and is statistically significant at the 0.01 level (two‑tailed). Conclusion: The prevalence rate of oral mucosal lesions in patients with dermatological diseases was relatively low. However, predominant oral mucosal lesions observed in the study were autoimmune in origin with a high morbidity and mortality index. Hence, multidisciplinary approach will definitely help in the prognosis of patients.Keywords: Autoimmune disease, Dermatological manifestations, Immunofluorescence, India, Oral lesions, Prevalenc

Biological role of lectins: A review

Lectins comprise a stracturally vary diverse class of proteins charecterized by their ability to selectively bind carbohydrate moieties of the glycoproteins of the cell surface. Lectins may be derived from plants, microbial or animal sources and may be soluble or membrane bound. Lectins is a tetramer made up of four nearly identical subunits. In human, lectins have been reported to cause food poisoning, hemolytic anemia, jaundice, digestive distress, protein and carbohydrate malabsorption and type I allergies. The present review focuses on the classification, structures, biological significance and application of lectins