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This paper presents the design details of an integrated 4x4 element dual feed dual circularly polarized microstrip antenna array in the S-band. The dual circular polarization is achieved by the use of quadrature hybrids. Power division for the dual input array is achieved through two 1x16 equal split equal phase corporate feed networks. The quadrature hybrids and corporate feeds for the proposed array are designed in multilayer printed circuit boards (PCB) in stripline configuration. This antenna can be used to transmit or receive both right-handed circularly polarized (RHCP) waves or left-handed circularly polarized (LHCP) waves simultaneously or one at a time by terminating the other port with 50Ω resistance. The proposed antenna has 700MHz of 10 dB impedance bandwidth (27%), 400MHz of 3dB axial ratio bandwidth and 300MHz of 3dB gain bandwidth centred at 2.5GHz with a peak gain of 15.5dB in both polarizations. It has a 3dB beam width of 26° and cross-polarization levels below 20dB in both the polarizations. Design and simulation of patch array, quadrature hybrids and 1x16 corporate feeds in multilayer configuration, PCB stack-ups, fabrication, integration and testing processes are discussed in detail. The effect of thermal protection system (TPS) of the re-entry vehicle on antenna performance parameters was studied and presented. [ABSTRACT FROM AUTHOR]

A compact asymmetric coplanar strip fed monopole antenna for multiband applications is presented. The antenna exhibits three resonances around 1.8, 2.4, and 5.6 GHz covering the DCS/PCS/UMTS/IEEE 802.11b/g/IEEE802.11a/HIPERLAN2 bands. The multiband characteristic of the antenna is due to the various meandered current paths excited in the radiating structure. The antenna has an overall dimension of only 28 x 30 [mm.sup.2] when printed on a substrate of dielectric constant 4.4. The uniplanar design, simple feeding technique and compactness make it easy for the integration of the antenna into circuit boards. Details of the antenna design, experimental and simulated results are presented and discussed. Index Terms--Asymmetric coplanar strip (ACS), mobile antennas, monopole antennas, multiband antennas, printed antennas, uniplanar.

A novel compact microstrip fed dual-band coplanar antenna for wireless local area network is presented. The antenna comprises of a rectangular center strip and two lateral strips printed on a dielectric substrate and excited using a 50 [ohm] microstrip transmission line. The antenna generates two separate resonant modes to cover 2.4/5.2/5.8 GHz WLAN bands. Lower resonant mode of the antenna has an impedance bandwidth (2:1 VSWR) of 330 MHz (2190-2520 MHz), which easily covers0 the required bandwidth of the 2.4 GHz WLAN, and the upper resonant mode has a bandwidth of 1.23 GHz (4849-6070 MHz), covering 5.2/5.8 GHz WLAN bands. The proposed antenna occupy an area of 217 [mm.sup.2] when printed on FR4 substrate ([[epsilon].sub.r] = 4.7). A rigorous experimental study has been conducted to confirm the characteristics of the antenna. Design equations for the proposed antenna are also developed. Index Terms--Coplanar wavegnide, dual-band antennas, printed antennas, wireless local area networks (WLANs).

The article presents several case studies related to metformin-Induced Chronic Diarrhea and Weight Loss in diabetic patients. Topics discussed include information on probable precipitating factors like nephropathy or drugs increasing metformin levels; rise in discontinuation and nonadherence rates of patients due to side effects; and need for withholding metformin before subjecting patients to detailed, invasive, and expensive investigations.

• Diabetic foot osteomyelitis is difficult to diagnose and treat. Microbial pattern and their resistance can vary geographically. • Concordance rate of organisms was 66% when both bone culture and deep soft-tissue culture grew organisms. • Polymicrobial infections were seen in a very small proportion (about 5%). After Staphylococcus, Pseudomonas was second common organism that grew in cultures. • This is the first study detailing the microbial pattern of diabetic foot osteomyelitis using deep tissue culture and comparing with bone culture from India. Diabetic foot osteomyelitis (DFO) is a dreaded complication as both diagnosis and treatment of the condition is laborious. However, for proper decision on antibiotics in medical management of DFO, accurate determination of microbes is necessary to narrow the spectrum of coverage and to reduce adverse effects of long-term administration of antibiotics. With differing pattern of use of antimicrobials and their resistance pattern in different countries, it is empirical to determine the microbiological characteristics of bone cultures in DFO from a referral institute in South India. This study was a retrospective chart review of all cases of proven DFO who had consented for debridement and bone culture or those who underwent amputation. Both deep soft tissue (DST) and bone cultures were obtained for aerobic bacteria. Clinical characteristics and site(s) of DFO were recorded. Investigations for peripheral artery disease were performed if clinically indicated. In all, 105 patients with DFO were reviewed. Mean age was 62 years and 70% were men. Of those who were screened, 57% had evidence of peripheral arterial disease by arterial doppler. 46% of bone culture samples were sterile. Gram- negative organisms were more common (58%). Following staphylococcus, pseudomonas was the second common isolate. Of total staphylococcal isolates 37% were MRSA and 33% of klebsiella isolates were ESBL producing. Concordance rate between DST and bone cultures was 66%. 90% were mono-bacterial isolates. The commonest site of involvement of DFO was terminal phalanges of toes rather than base of 1st metatarsal. Widespread use of antibiotics, tropical climate and route of entry of organisms causing DFO differed in our cohort of patients. Further studies from different regions of world would shed light onto different pattern of microbes causing DFO. [ABSTRACT FROM AUTHOR]

Fine particles of nickel ferrite are synthesized by the sol-gel technique and characterized by the X-ray diffraction method. These materials are incorporated in ethylene propylene diene rubber (EPDM) according to a specific recipe for various loadings. The rubber ferrite composites (RFCs) thus obtained have several applications, such as microwave absorbers, EMI shielding materials, etc. In the present study, microwave attenuation and dielectric properties of RFCs are studied in the X- and S-band frequencies. Real and imaginary parts of the dielectric permittivity are determined by cavity perturbation method. Dielectric permittivity in X-band frequency, based on Maxwell-Garnet equation is calculated and presented here. [ABSTRACT FROM AUTHOR]

TeO2 particle-filled PTFE composites were prepared by the powder processing technique. The structure and microstructure of the composites were investigated by X-ray diffraction and scanning electron microscopic methods. The effect of the ceramic content (0–0.6 volume fraction) of TeO2 on the dielectric properties of the composites was studied at 1 MHz and 7 GHz. The dielectric constant and dielectric loss increased with an increase in the TeO2 content. For 60 vol% of TeO2, the composite has a dielectric constant of 5.4 and a loss tangent of 0.006 at 7 GHz. The measured dielectric constant (ℇr) is compared with the effective dielectric constant calculated using different theoretical models. The observed dielectric constants are in agreement with that calculated using effective medium theory. The coefficient of thermal expansion of the composites decreases with the TeO2 content, reaching a minimum of 32 ppm/°C for 60 vol% loading. [ABSTRACT FROM AUTHOR]

A compact asymmetric coplanar strip, fed monopole antenna for multiband applications is presented. The antenna exhibits three resonances around 1.8, 2.4, and 5.6 GHz covering the DCS/PCS/UMTS/IEEE 802.11b/g/IEEE802.11a/HIPERLAN2 bands. The multiband characteristic of the antenna is due to the various meandered current paths excited in the radiating structure. The antenna has an overall dimension of only 28 × 30 mm2 when printed on a substrate of dielectric constant 4.4. The uniplanar design, simple feeding technique and compactness make it easy for the integration of the antenna into circuit boards. Details of the antenna design, experimental and simulated results are presented and discussed. [ABSTRACT FROM AUTHOR]

A compact dual band folded dipole antenna printed on either side of a substrate and excited by a 50 Ω microstrip line with a truncated ground plane covering DCS/PCS/2.4 GHz WLAN bands is presented. In the proposed design, a microstrip-fed folded monopole antenna is first designed and then modified it to a microstrip-fed folded dipole by placing another folded arm on the opposite side of the substrate extending from the ground plane, for achieving dual resonance. The antenna resonating at 1.87 GHz and 2.46 GHz has 2:1 VSWR bandwidth of 17% and 9% respectively. The proposed antenna offers 53% area reduction compared to a standard rectangular microstrip antenna. Details of the antenna design and experimental results are presented. [ABSTRACT FROM AUTHOR]

A compact dual-band antenna operating in the 1.8/2.4-GHz bands with identical linear polarization suitable for DCS/2.4-GHz WLAN applications is presented. The proposed configuration is a modified microstrip-fed printed monopole with an additional strip and a proper truncated ground plane on the opposite side of the substrate. The proposed antenna of dimensions 35 × 47 × 1.6 mm offers 2:1 VSWR bandwidths of 10.8% and 9.8% in the DCS and 2.4-GHz WLAN bands, respectively. Details of the antenna design and experimental results are discussed. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 856–859, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21498 [ABSTRACT FROM AUTHOR]

Development of a compact microstrip-fed, branched monopole antenna for ultra wide band (UWB) applications is presented. By suitably embedding branches on the top edge of the strip monopole, an UWB response can be easily achieved by merging different resonances. The simulated and experimental results demonstrate that the proposed antenna achieves more than 3:1 impedance bandwidth for 2:1 VSWR criteria. The antenna exhibits nearly omni directional radiation characteristics and moderate gain in the entire band. The proposed antenna is printed on a FR4 substrate of ℇr = 4.4 and thickness h = 1.6 mm and having an overall dimension of 65 × 35 mm2 including the ground plane. The parameters that affect the performance of the antenna are presented and discussed. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 45–47, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22045 [ABSTRACT FROM AUTHOR]

The design and radiation characteristics of a wide band dumbbell-shaped patch excited by planar strip monopole with truncated ground plane is proposed in this letter. The antenna can be easily modified for dual band operation by adjusting the location of the patch over the planar monopole. The antenna offers a bandwidth of 35 and 9% at 3.2 and 5.3 GHz bands, respectively. The overall area of the antenna including the 50 Ω line feed is only 65 × 65 mm2. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2295–2296, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21926 [ABSTRACT FROM AUTHOR]

Renewable energy is considered to be one of the viable options in consideration of intense economic development and increasing energy consumption. With maturity of advanced technologies, economical viable and environmental friendly, wind energy has become one of the fastest growing sources of renewable energy in the world. This study focuses on the combined use of geographic information systems (GIS) and spatial multi-criteria decision analysis for selecting the most appropriate sites for wind-farm development projects. This paper utilized wind speed data over a period of almost 20 years between 1991 and 2010 from different stations to assess the wind power potential sites. The wind energy potential zones were grouped into four categories as “high suitable”, “moderate suitable”, “low suitable” and “not suitable”. The results show that the study area has 12.20% (2787.78 km 2 ) as high suitable, 17.06% (3899.78 km 2 ) as moderate suitable and 11.06% (2528.61 km 2 ) as low suitable. The most potential suitable sites were located in the northwestern (along Osian, Shergargh, Dechu, and Shaitrawa, Phalodi) of Jodhpur district, India. This scientific approach will enable resource managers during planning process to make informed decisions. [ABSTRACT FROM AUTHOR]

Background: Co-existence of type 2 diabetes and hypothyroidism is an emerging trend observed in clinical practice. Although the effects of isolated type 2 diabetes and hypothyroidism are well known, there are limited studies addressing the metabolic complications when these two conditions co-exist. The aim of the present study was to assess the interaction between type 2 diabetes and hypothyroidism with respect to glucose tolerance, dyslipidemia and redox balance in a state were these two diseases coexist. Methods: Sixty male Wistar Albino rats were randomised into six groups. Group 1: control, Group 2: overt hypothyroidism, Group 3: mild hypothyroidism, Group 4: type 2 diabetes, Group 5: mild hypothyroidism + type 2 diabetes, Group 6: overt hypothyroidism + type 2 diabetes. Experimental hypothyroidism was created by the administration of propyl-2-thiouracil and type 2 diabetes by feeding rats with 60% fructose (w/w). The duration of the study was 6 weeks. All the parameters were estimated at the start (basal) and the end of the study. Intraperitoneal glucose tolerance test was carried out and area under curve (AUC) calculated to assess the glucose tolerance. Thyroid profile, lipid profile and oxidative stress parameters were also measured. Results: Plasma TSH level was elevated 3-fold in the mild hypothyroid group and 15.2-fold in the overt hypothyroid group in comparison to the control group. Thyroid profile was found to be normal in type 2 diabetic group. There was no significant difference between hypothyroidism and hypothyroidism + diabetes groups with respect to thyroid profile. Among the six groups the degree of glucose intolerance was found to be maximum for overt hypothyroidism + diabetes group, followed by diabetes group and overt hypothyroidism group. An interesting finding was that glucose intolerance was significantly reduced in mild hypothyroidism + diabetes group (increase in AUC: 48.04%) in comparison with isolated diabetes group (increase in AUC: 71.63%). Similar results were obtained with parameters of oxidative stress. Oxidative stress was observed in overt hypothyroidism + diabetes, diabetes, overt hypothyroidism groups with severity decreasing in that order. Coexistence of mild hypothyroidism with diabetes decreased oxidative stress in comparison with isolated diabetes group. There was no statistical difference in lipid profile between mild hypothyroidism + diabetes and isolated diabetes group. Conclusion: Presence of mild hypothyroidism in type 2 diabetes confers a protective effect with respect to glucose tolerance and redox balance whereas presence of overt hypothyroidism in type 2 diabetes has a deleterious effect. The increased incidence of hypothyroidism in diabetes, especially subclinical hypothyroidism, could be a reflection of a physiological attempt by the body to mitigate damage wrought by diabetes. [ABSTRACT FROM AUTHOR]

Introduction Extensive use of upper gastrointestinal endoscopy (UGE) with the advent of open access centers has resulted in inappropriate endoscopies. Our study aimed to evaluate the appropriateness of American Society for Gastrointestinal Endoscopy (ASGE) guidelines for UGE and to assess the diagnostic yield of endoscopy in a tertiary care center in South India. Methods The study was conducted as a prospective analytical study. Indications for endoscopy were classified as "ASGE appropriate" and "ASGE inappropriate". The significance of association of ASGE guidelines and other categorical variables with endoscopic findings were assessed. Results ASGE appropriate indications and inappropriate indications accounted for 85.9% and 14.1% of endoscopies, respectively. The most common appropriate indication was persistent dyspepsia despite adequate proton-pump inhibitor (PPI) therapy (28.1%) and the only inappropriate indication for endoscopy was isolated dyspepsia without adequate PPI therapy (14.1%). The diagnostic yield of endoscopy for appropriate indications was 69.5% and for inappropriate indications was 55.1%, the difference was statistically significant (P= 0.003; OR-1.857). The sensitivity and specificity of ASGE guidelines was 88.5% and 19.5%, respectively. Conclusion According to our study, ASGE guidelines may be considered as appropriate guidelines for UGE in our population and these guidelines were followed 85.9% of the times in referring patients for the same. However, the high diagnostic yield even in inappropriate endoscopies indicates the necessity of further studies that might identify other relevant indications for endoscopy, thus avoiding misutilization of resources without missing out on relevant cases., Competing Interests: The authors have declared that no competing interests exist.