Search

Efficient adsorption of Ba ions was achieved using Sn@TiO 2 nanocomposite generated by ultrasonication process with subsequent calcination at 300 °C. X-ray diffraction, nitrogen adsorption-desorption isotherm, X-ray photoelectron spectroscopy, Fourier transformer infra-red, and scanning/transmission electron microscopy analyses were performed to probe the structural and textural features of the adsorbent powder. The XPS, FTIR, and EDX analyses confirmed the Sn doping into TiO 2 host lattice. Some interesting features, including the increase of crystallite size and lattice parameters, were attained due to the successful Sn incorporation into the TiO 2 host, as indicated further by XRD analysis. The sorption results fitted the Langmuir isotherm model and the kinetic data complied with the pseudo-second-order kinetics. The adsorption process improved markedly above the pHzc due to the electrostatic attraction between the negatively charged Sn@TiO 2 particles' surface and the positively charged Ba ions. The achieved high-performance mesoporous Sn@TiO 2 nanostructures for the adsorption of Ba2+ could be potentially utilized to remove other toxic metal cations. [ABSTRACT FROM AUTHOR]

A compact fabric antenna structure integrated with electromagnetic bandgap structures (EBGs) covering the desired frequency spectrum between 2.36 GHz and 2.40 GHz for Medical Body-Area Networks (MBANs), is introduced. The needs of flexible system applications, the antenna is preferably low-profile, compact, directive, and robust to the human body's loading effect have to be satisfied. The EBGs are attractive solutions for such requirements and provide efficient performance. In contrast to earlier documented EBG backed antenna designs, the proposed EBG behaved as shielding from the antenna to the human body, reduced the size, and acted as a radiator. The EBGs reduce the frequency detuning due to the human body and decrease the back radiation, improving the antenna efficiency. The proposed antenna system has an overall dimension of 46×46×2.4 mm3. The computed and experimental results achieved a gain of 7.2 dBi, a Front to Back Ratio (FBR) of 12.2 dB, and an efficiency of 74.8%, respectively. The Specific Absorption Rate (SAR) demonstrates a reduction of more than 95% compared to the antenna without EBGs. Moreover, the antenna performance robustness to human body loading and bending is also studied experimentally. Hence, the integrated antenna-EBG is a suitable candidate for many wearable applications, including healthcare devices and related applications. [ABSTRACT FROM AUTHOR]

The human leukocyte antigen (HLA)-A03 group has more than 90 known members and is one of the largest families of HLA class I alleles, with the most common variant being HLA-A0301. In this study, we determined the peptide-binding motif of the highly frequent Sudanese allele A0302 and compared it with the previously published peptide-binding motif of A0301. The two alleles differ only at two distinct residues Glu152Val and Leu156Gln, which are predicted to be part of specificity pockets D, C and E and thus in contact with the peptide. Soluble recombinant A0302 was expressed, affinity purified and the bound peptides were then eluted and analysed by mass spectrometry. The peptide-binding motif of A0302 differs significantly from the previously published HLA-A0301 and the Glu152Val/Leu156Gln mismatches appear to have a significant impact on the peptide-binding features of A0302 and A0301. [ABSTRACT FROM AUTHOR]

The major histocompatibility complex (MHC) is the most polymorphic region of the human genome. Human leukocyte antigen-C (HLA-C) genes are located in the class I region of MHC. Most polymorphisms of HLA class I antigens are present in exons 2 and 3, which encode the α1 and α2 domains of the HLA-A heavy chain, involved in both peptide binding and HLA-restricted recognition by the T-cell receptor. Four new HLA-Cw alleles were identified in the Sudanese population during HLA class I and class II sequencing-based typing at the HLA-C locus of case–control study of Sudanese HIV patients, in individuals from different ethnic background. Based on the localization of the affected amino acid positions in an outer loop of the α-helix forming the side of the peptide-binding groove, we do not expect the replacement mutations to have an effect on peptide binding or T-cell receptor interaction. [ABSTRACT FROM AUTHOR]

Millimetre-wave frequencies are promising for sensitive detection of glucose levels in the blood, where the temperature effect is insignificant. All these features provide the feasibility of continuous, portable, and accurate monitoring of glucose levels. This paper presents a metamaterial-inspired resonator comprising five split-rings to detect glucose levels at 24.9 GHz. The plexiglass case containing blood is modelled on the sensor's surface and the structure is simulated for the glucose levels in blood from 50 mg/dl to 120 mg/dl. The novelty of the sensor is demonstrated by the capability to sense the normal glucose levels at millimetre-wave frequencies. The dielectric characteristics of the blood are modelled by using the Debye parameters. The proposed design can detect small changes in the dielectric properties of blood caused by varying glucose levels. The variation in the transmission coefficient for each glucose level tested in this study is determined by the quality factor and resonant frequency. The sensor presented can detect the change in the quality factor of transmission response up to 2.71/mg/dl. The sensor's performance has also been tested to detect diabetic hyperosmolar syndrome. The sensor showed a linear shift in resonant frequency with the change in glucose levels, and an R2 of 0.9976 was obtained by applying regression analysis. Thus, the sensor can be used to monitor glucose in a normal range as well as at extreme levels. [ABSTRACT FROM AUTHOR]

At present, strenuous efforts are being made to enhance the TiO2 photocatalyst by doping it with Sn. However, there is still scarcity in the reports on the synthesis of a superior TiO2 photocatalyst in an efficient and simple manner. Therefore, Sn (0-5%) doped TiO2photocatalyst for low-cost photocatalysis and free additive were successfully fabricated through a facile method. The obtained nanomaterials were calcined at 300° C for 2h and characterized using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier Transform Infrared spectroscopy (FTIR), and Energy Dispersive Spectrometer (EDS). The findings demonstrated that, the annealed Sn doped TiO2 has a good crystallinity and moderated adsorption capacity as well as a superior photocatalysis competence for degradation of Indigo Carmine (IC) dye. [ABSTRACT FROM AUTHOR]

In this review, we present for the first time an integrated version of the G ene[rate] computer tools which have been developed during the last 5 years to analyse human leukocyte antigen ( HLA) data in human populations, as well as the results of their application to a large dataset of 145 HLA-typed population samples from Europe and its two neighbouring areas, North Africa and West Asia, now forming part of the G ene[va] database. All these computer tools and genetic data are, from now, publicly available through a newly designed bioinformatics platform, HLA-net, here presented as a main achievement of the HLA-NET scientific programme. The G ene[rate] pipeline offers user-friendly computer tools to estimate allele and haplotype frequencies, to test Hardy-Weinberg equilibrium ( HWE), selective neutrality and linkage disequilibrium, to recode HLA data, to convert file formats, to display population frequencies of chosen alleles and haplotypes in selected geographic regions, and to perform genetic comparisons among chosen sets of population samples, including new data provided by the user. Both numerical and graphical outputs are generated, the latter being highly explicit and of publication quality. All these analyses can be performed on the pipeline after scrupulous validation of the population sample's characterisation and HLA typing reporting according to HLA-NET recommendations. The G ene[va] database offers direct access to the HLA-A, -B, -C, - DQA1, - DQB1, - DRB1 and - DPB1 frequencies and summary statistics of 145 population samples having successfully passed these HLA-NET 'filters', and representing three European subregions (South-East, North-East and Central-West Europe) and two neighbouring areas (North Africa, as far as Sudan, and West Asia, as far as South India). The analysis of these data, summarized in this review, shows a substantial genetic variation at the regional level in this continental area. These results have main implications for population genetics, transplantation and epidemiological studies. [ABSTRACT FROM AUTHOR]

We present here the results of the Analysis of HLA Population Data ( AHPD) project of the 16th International HLA and Immunogenetics Workshop (16 IHIW) held in Liverpool in May-June 2012. Thanks to the collaboration of 25 laboratories from 18 different countries, HLA genotypic data for 59 new population samples (either well-defined populations or donor registry samples) were gathered and 55 were analysed statistically following HLA- NET recommendations. The new data included, among others, large sets of well-defined populations from north-east Europe and West Asia, as well as many donor registry data from European countries. The Gene[ rate] computer tools were combined to create a Gene [ rate ] computer pipeline to automatically (i) estimate allele frequencies by an expectation-maximization algorithm accommodating ambiguities, (ii) estimate heterozygosity, (iii) test for Hardy-Weinberg equilibrium (HWE), (iv) test for selective neutrality, (v) generate frequency graphs and summary statistics for each sample at each locus and (vi) plot multidimensional scaling ( MDS) analyses comparing the new samples with previous IHIW data. Intrapopulation analyses show that HWE is rarely rejected, while neutrality tests often indicate a significant excess of heterozygotes compared with neutral expectations. The comparison of the 16 IHIW AHPD data with data collected during previous workshops (12th-15th) shows that geography is an excellent predictor of HLA genetic differentiations for HLA-A, -B and - DRB1 loci but not for HLA- DQ, whose patterns are probably more influenced by natural selection. In Europe, HLA genetic variation clearly follows a north to south-east axis despite a low level of differentiation between European, North African and West Asian populations. Pacific populations are genetically close to Austronesian-speaking South-East Asian and Taiwanese populations, in agreement with current theories on the peopling of Oceania. Thanks to this project, HLA genetic variation is more clearly defined worldwide and better interpreted in relation to human peopling history and HLA molecular evolution. [ABSTRACT FROM AUTHOR]