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This paper presents a comprehensive review of symmetrically shaped antennas in terms of antenna size, dielectric materials, resonating band, peak gain, radiation pattern, simulating tools, and their applications. In this article, flower shape, leaf shape, tree shape, fan shape, Pi shape, butterfly shape, bat shape, wearable, multiband, monopole, and fractal antennas are discussed. Further, a survey of previously reported bandwidth enhancement techniques of microstrip patch antenna like introduction of thick and lower permittivity substrate, multilayer substrate, parasitic elements, slots and notches, shorting wall, shorting pin, defected ground structure, metamaterial-based split ring resonator structure, fractal geometry, and composite right-hand/left-handed transmission line approach is presented. The physics of these techniques has been discussed in detail which is supported by circuit theory model approach. [ABSTRACT FROM AUTHOR]

Summary: The research presented in this paper is intended to design and analyze of a triple‐band stub and notches loaded antenna for wireless applications. The optimized and proposed antenna (Antenna‐4: 0.235λ0 × 0.238λ0 × 0.013λ0 mm3) is decided after systematic investigation of Antennas‐1 to ‐4 at design frequency of 2.45 GHz. One orthogonal and two parallel notches and one stub are used on the radiating patch of the substrate to obtain the desired specifications. Theoretical analysis based on circuit theory model has been performed to obtain the equivalent circuit of the proposed antenna. Antenna parameters are analyzed by means of IE3D electromagnetic solver and circuit theory model, and results are validated with experimental results. The impedance bandwidths (S11 < –10 dB) of the proposed antenna are 41.3% between 1.42 and 2.16 GHz (theoretical), 21.6% between 1.61 and 2 GHz (simulated), and 41.4% between 1.40 and 2.13 GHz (measured) at lower resonant frequency (fr1=1.98GHz); 4.1% between 2.61 and 2.72 GHz (theoretical), 17.4% between 2.36 and 2.81 GHz (simulated), and 8.8% between 2.50 and 2.73 GHz (measured) at middle resonant frequency (fr2=2.65GHz); and 42.3% between 3.32 and 5.10 GHz (theoretical), 49.9% between 3.04 and 5.06 GHz (simulated), and 44.4% between 2.98 and 4.68 GHz (measured) at higher resonant frequency (fr3=3.40GHz) observed, respectively. The measured stable peak gain of 2.6 dB at 1.9 GHz, 3.8 dB at 2.6 GHz, and 5.4 dB at 3.6GHz is observed in lower, middle, and higher bands, respectively. [ABSTRACT FROM AUTHOR]

In this paper, a simple and compact rectangular microstrip antenna of H-shape patch has been designed by successively loading rectangular notches of different dimensions and square slots in radiating patch. The conventional microstrip antenna suffers with narrow impedance bandwidth. The current work affords an alternate option to enhance the bandwidth. The bandwidth of recommended microstrip antenna has been obtained 35.61% (<-10dB) and antenna is resonating in single band with two resonant frequencies at 1.729GHz (lower resonant frequency) and 2.223GHz (higher resonant frequency). The recommended antenna has frequency band in the range of 1.639GHz-2.349GHz and it is appropriate for S-band (2-4GHz) and other wireless applications. The return loss of the recommended antenna is -16.97dB at 1.729GHz and -20.14dB at 2.223GHz. The recommended microstrip antenna is directly fed by 50O microstrip line feed. The recommended antenna has been designed, simulated and analyzed by IE3D simulation software. [ABSTRACT FROM AUTHOR]

Introduction: Alpinia galanga Linn. belongs to the family Zingiberaceae has been used as a traditional medicine in China for relieving stomach ache, treating cold, invigorating the circulatory systems, diabetes, and reducing swelling. Aim: To evaluate the antidiabetic activity of methanolic extract of A. galanga aerial parts on streptozotocin (STZ) induced diabetic rats. Materials and Methods: Diabetes was induced by single intraperitoneal injection of STZ at a dose of 60 mg/kg bodyweight. Test drug methanolic extract of A. galanga (200 and 400 mg/kg b.w.) and glibenclamide (10 mg/kg b.w.) as standard drug was administered orally for 21 consecutive days in STZ-induced diabetic rats. Fasting blood glucose level, serum lipid profiles, as well as initial and final changes in body weight were assessed along with histopathology. All the parameters were statistically analyzed by using one-way ANOVA followed by Bonferroni t-test. Results: Experimental findings showed significant dose dependent antidiabetic potential of methanolic extract in terms of reduction of fasting blood glucose level and various biochemical parameters in diabetic rats when compared with that of the diabetic control group, which might be due to the stimulatory effect of methanolic extracts on the regenerating β-cells and also on the surviving β-cells. Conclusion: Methanolic extract of aerial parts of A. galanga was effective in controlling blood glucose level and improve lipid profile in euglycemic as well as diabetic rats. [ABSTRACT FROM AUTHOR]

Objective To evaluate the diagnostic pharmacognostical characters of Costus speciosus (aerial parts) along with their physico-chemical parameters and fluorosence analysis. Method The pharmacognostical characters were determined in terms of macroscopy, microscopy, powder microscopy, leaf constant, fluorescence analysis and preliminary phytochemical investigation. Results The findings of macroscopy revealed that leaves elliptic to oblong or oblong-lancoelate, thick, spirally arranged, with stem clasping sheaths up to 4 cm, flowers large, white, cone-like terminal spikes, with bright red bracts. Transverse section of leaflet showed the presence of cuticularised epidermis with polygonal cells on adaxial surface and bluntly angled cells on abaxial surface of lamina, mesophyll cells differentiated in to single layered palisade cells on each surface and 2-3 layered spongy parenchyma, unicellular and uniseriate multicellular covering trichomes, paracytic stomata and vascular bundles surrounded by sclerenchymatous multicellular sheath. Preliminary phytochemical screening exhibited the presence of various phytochemical groups like alkaloids, glycosides, steroids, phenolic constituents. Further, the leaf constants, powder microscopy and fluorescence characteristics indicated outstanding results from this investigation Conclusions Various pharmacognostical and physico-chemical parameters have pivotal roles in identification, authentication and establishment of quality parameters of the species. [ABSTRACT FROM AUTHOR]