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A planar dual-element multi-generation compatible MIMO antenna is presented in this paper. The radiating antenna elements are designed to resonate over two frequency ranges: 1.41 GHz - 2.11 GHz and 3.6 GHz - 3.8 GHz, with (S11/S22) reference considered as -10 dB,covering frequencies allotted for L1 GPS, 2G standards (GSM-1800 and GSM-1900), 3G standard (UMTS), LTE (working on TDD and FDD techniques) and 5G New Radio. The designed antenna is optimized using IE3D simulation software and fabricated on FR4 substrate having relative permittivity of 4.4, loss tangent of 0.02 and thickness of 1.6 mm. A three step isolation improvement and impedance bandwidth enhancement technique is presented to reduce the mutual coupling and cover the desired frequency range. Antenna characteristics in terms of the reflection coefficient, mutual coupling, radiation pattern and gain are measured and show good agreement with the simulated results. Diversity performance is evaluated in terms of the envelop correlation coefficient. It is found to be less than 0.12 and 0.06 in the first and second bands of frequencies, respectively. The planar structure and capability to support several frequencies of multiple generations make the proposed MIMO antenna a good candidate for integration with future wireless devices. [ABSTRACT FROM AUTHOR]

The emergence of drug resistance in Streptococcus pneumoniae (Spn) is a global health threat and necessitates discovery of novel therapeutics. The serine acetyltransferase (also known as CysE) is an enzyme of cysteine biosynthesis pathway and is reported to be essential for the survival of several pathogenic bacteria. Therefore, it appears to be a very attractive target for structure–function understanding and inhibitor design. This study describes the molecular cloning of cysE from Spn in the pET21c vector and efforts carried out for expression and purification of active recombinant CysE. Significant expression of recombinant Spn cysE could be achieved in codon optimized BL21(DE3)-RIL strain as opposed to conventional BL21(DE3) strain. Analysis of codon adaptation index (CAI) with levels of eukaryotic genes and prokaryotic cysEs expressed in heterologous E. coli host suggests that codon optimized E. coli BL21(DE3)-RIL may be a better host for expressing genes with low CAI. Here, an efficient protocol has been developed for recovery of recombinant Spn CysE in soluble and biologically active form by the usage of nonionic detergent Triton X-100 at a concentration as low as 1%. Altogether, this study reports a simple strategy for producing functionally active Spn CysE in E. coli. [ABSTRACT FROM AUTHOR]

This paper reports the study of structural, morphological and microwave dielectric properties of CoO added corundum type MgNbO ceramics, sintered at 1200-1300 °C. The samples were prepared by solid state reaction method. X-ray diffraction patterns of these samples confirm the phase (Mg Co)NbO along with a small percentage of secondary phase MgNbO. The SEM micrographs suggest the gradual grain growth with the increase in Co addition as well as sintering temperature. The microwave dielectric properties of sintered ceramics were investigated by dielectric resonator method and they show a strong dependence on their composition, densification and microstructure. A good combination of dielectric properties with dielectric constant (ε) of 16.69, quality factor ( Qf) of 65,849 GHz (at 9.3 GHz) and nearly zero temperature coefficient of resonant frequency ( $${\tau }_{f}$$ ) have been obtained for (MgCo)NbO composition, sintered at 1275 °C. The design of a coupler circuit was simulated by Sonnet Lite software and then fabricated on this thermal stable ceramic taking centre frequency as 2 GHz. The experimental result resembles well with the simulated result and shows ~70% size reduction as compared to a similar circuit designed on FR4 substrate. [ABSTRACT FROM AUTHOR]

This paper presents a two-element MIMO antenna configuration designed using magneto-dielectric (MD) material. The MD material has been designed such that its temperature coefficient value approaches zero. The microwave dielectric constant and permeability of the material is calculated by Nicholson-Ross-Weir conversion technique and found to be 8.02 and 1.64, respectively. Each element is designed so that it can operate at 5.71 GHz. The two elements of the MIMO configuration are separated by quarter wavelength and half wavelength and are compared. The designed antenna can give a quad-directional radiation property, which can be utilized for the diversity scheme. [ABSTRACT FROM AUTHOR]

Adult cases of visceral leishmaniasis (VL), predominantly males, have been reported in the past decade from natives of high altitude areas of North Indian state of Uttarakhand. We report 14 pediatric cases of VL, who were diagnosed and treated successfully over the past 7 years. All these children were born and brought up in this area and had never visited any of the endemic areas. High prevalence of pallor, splenohepatomegaly, thrombocytopenia and poor association with HIV are cardinal features of VL in this region. Although newer drugs have become available, the protozoan continues to be sensitive to sodium stibogluconate. We conclude that the transmission cycle of VL has been established in this region and VL should be considered in the differential diagnosis of any child presenting with fever and hepatosplenomegaly. However, molecular and epidemiological studies are needed to identify the ancestry, vector and animal reservoir if any in this region. [ABSTRACT FROM AUTHOR]