26 research outputs found

    Space-Frequency Equalization for Broadband Single Carrier MIMO Systems

    Get PDF
    In this paper, a frequency domain (FD) receiver architecture implemented using estimated channel parameters is derived for broadband single carrier modulations. Co-channel and inter-symbol interferences are compensated by a minimum mean squared error based integrated space-frequency-equalizer (SFE) using the estimated parameters. The integrated SFE in the FD consists of coupled FIR structures, that are jointly optimized by maximizing the desired signal to interference plus noise ratio. We develop analytical expressions and present simulation results for the integrated SFE. Simulation results demonstrate that excellent receiver performance is achieved even for channels with large ISI spans. The proposed SC-SFE outperforms previous layered space frequency (LSF) receivers with imperfect channel knowledge. Further, the parallel receiver architecture yields equal diversity gains to all data streams without the error propagation that is common to most LSF schemes

    A study on the prevalence of obesity and metabolic syndrome among students of a medical college

    Get PDF
    Background: Obesity is emerging as a serious problem throughout the world. The overall life expectancy is significantly shortened and the quality of life decreased in those who are excessively overweight. Metabolic syndrome (MetS) is characterized by a constellation of individual risk factors of cardiovascular disease. Central obesity is a key feature of this syndrome, reflecting the fact that the syndrome’s prevalence is driven by strong relationship between waist circumference and increasing obesity. Awareness about MetS in medical students is the need of the hour.Methods: This cross-sectional study was conducted at Dr. PSIMS and RF, Chinnoutpalli, Andhra Pradesh, India involving 400 medical students. A pre-tested questionnaire, measurement of blood pressure, fasting glucose level, fasting lipid profile, anthropometric variables such as height, weight, waist circumference and hip circumference were taken. Metabolic syndrome was defined based on the International Diabetes Federation criteria. Data was processed using SPSS version 16. T-test, chi-square test, fisher’s exact test, anova and odd’s ratio were used for statistical analysis.Results: 59% of the study population was female. The prevalence of obesity was 4%, with majority being males (81.25%) The MetS prevalence as per the International diabetes federation (IDF) criteria was 6% (n=24). The prevalence of MetS in males was 12.19% (n=20) and in females 1.69%. (n=4). The risk of developing metabolic syndrome is high among those who smoke, consume alcohol, consume junk food and sleep for longer durations.Conclusions: The prevalence of metabolic syndrome is 6%. A significant association is established between life style habits like smoking, alcohol consumption, junk food consumption, sleep duration and MetS

    Identification of Stage-Specific Breast Markers using Quantitative Proteomics

    Get PDF
    YesMatched healthy and diseased tissues from breast cancer patients were analyzed by quantitative proteomics. By comparing proteomic profiles of fibroadenoma (benign tumors, three patients), DCIS (noninvasive cancer, three patients), and invasive ductal carcinoma (four patients), we identified protein alterations that correlated with breast cancer progression. Three 8-plex iTRAQ experiments generated an average of 826 protein identifications, of which 402 were common. After excluding those originating from blood, 59 proteins were significantly changed in tumor compared with normal tissues, with the majority associated with invasive carcinomas. Bioinformatics analysis identified relationships between proteins in this subset including roles in redox regulation, lipid transport, protein folding, and proteasomal degradation, with a substantial number increased in expression due to Myc oncogene activation. Three target proteins, cofilin-1 and p23 (increased in invasive carcinoma) and membrane copper amine oxidase 3 (decreased in invasive carcinoma), were subjected to further validation. All three were observed in phenotype-specific breast cancer cell lines, normal (nontransformed) breast cell lines, and primary breast epithelial cells by Western blotting, but only cofilin-1 and p23 were detected by multiple reaction monitoring mass spectrometry analysis. All three proteins were detected by both analytical approaches in matched tissue biopsies emulating the response observed with proteomics analysis. Tissue microarray analysis (361 patients) indicated cofilin-1 staining positively correlating with tumor grade and p23 staining with ER positive status; both therefore merit further investigation as potential biomarkers.Cyprus Research Promotion Foundation, Yorkshire Cancer Researc

    Rapid Dissolution of ZnO Nanoparticles Induced by Biological Buffers Significantly Impacts Cytotoxicity

    No full text
    Zinc oxide nanoparticles (nZnO) are one of the most highly produced nanomaterials and are used in numerous applications including cosmetics and sunscreens despite reports demonstrating their cytotoxicity. Dissolution is viewed as one of the main sources of nanoparticle (NP) toxicity; however, dissolution studies can be time-intensive to perform and complicated by issues such as particle separation from solution. Our work attempts to overcome some of these challenges by utilizing new methods using UV/vis and fluorescence spectroscopy to quantitatively assess nZnO dissolution in various biologically relevant solutions. All biological buffers tested induce rapid dissolution of nZnO. These buffers, including HEPES, MOPS, and PIPES, are commonly used in cell culture media, cellular imaging solutions, and to maintain physiological pH. Additional studies using X-ray diffraction, FT-IR, X-ray photoelectron spectroscopy, ICP-MS, and TEM were performed to understand how the inclusion of these nonessential media components impacts the behavior of nZnO in RPMI media. From these assessments, we demonstrate that HEPES causes increased dissolution kinetics, boosts the conversion of nZnO into zinc phosphate/carbonate, and, interestingly, alters the structural morphology of the complex precipitates formed with nZnO in cell culture conditions. Cell viability experiments demonstrated that the inclusion of these buffers significantly decrease the viability of Jurkat leukemic cells when challenged with nZnO. This work demonstrates that biologically relevant buffering systems dramatically impact the dynamics of nZnO including dissolution kinetics, morphology, complex precipitate formation, and toxicity profiles

    Microtia Reconstruction: Our Strategies to Improve the Outcomes

    No full text
    Introduction: Autologous costal cartilage framework placement is currently the gold standard in patients with microtia. In this article, we present the modifications developed by the author, generally following the principles established by Nagata, and discuss the technical details that have led us to achieve consistently stable and good long-term outcomes for auricular reconstruction in microtia. Materials and Methods: A retrospective review of microtia reconstruction performed from 2015 to 2021 was done. Those who underwent primary reconstruction for microtia and with a minimum follow-up of 6 months with documented photographs were included. Those who underwent secondary reconstruction for microtia and those who did not follow-up for a minimum period of 6 months were excluded. Outcomes were assessed with regard to appearance, and durability of the result. Influence of certain changes like delaying reconstruction until 15 years of age, use of nylon for framework fabrication, etc. over the outcome were assessed. Results: Of 11 ears reconstructed at less than 15 years of age, only one patient (9%) had a good long-term outcome, whereas of the 17 ears reconstructed at greater than 15 years of age, nine patients (53%) had a good long-term outcome. In our experience, infections and wire extrusions were the significant events related to severe cartilage resorption. Conclusion: In our experience, delaying the first stage to 15 years or later, using double-armed nylon sutures, and reducing the projection of the third layer of the framework in select cases have helped to improve our outcomes. Second stage of reconstruction can be avoided if patient is satisfied with the projection achieved in the first stage

    Electrostatic Interactions Affect Nanoparticle-Mediated Toxicity to Gram-Negative Bacterium \u3cem\u3ePseudomonas aeruginosa\u3c/em\u3e PAO1

    No full text
    Nanoscale materials can have cytotoxic effects. Here we present the first combined empirical and theoretical investigation of the influence of electrostatic attraction on nanoparticle cytotoxicity. Modeling electrostatic interactions between cells and 13 nm spheres of zinc oxide nanoparticles provided insight into empirically determined variations of the minimum inhibitory concentrations between four differently charged isogenic strains of Pseudomonas aeruginosa PAO1. We conclude that controlling the electrostatic attraction between nanoparticles and their cellular targets may permit the modulation of nanoparticle cytotoxicity

    Defect Engineering of ZnO Nanoparticles for Bioimaging Applications

    No full text
    Many promising attributes of ZnO nanoparticles (nZnO) have led to their utilization in numerous electronic devices and biomedical technologies. nZnO fabrication methods can create a variety of intrinsic defects that modulate the properties of nZnO, which can be exploited for various purposes. Here we developed a new synthesis procedure that controls certain defects in pure nZnO that are theorized to contribute to the n-type conductivity of the material. Interestingly, this procedure created defects that reduced the nanoparticle band gap to ∌3.1 eV and generated strong emissions in the violet to blue region while minimizing the defects responsible for the more commonly observed broad green emissions. Several characterization techniques including thermogravimetric analysis, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, Raman, photoluminescence, and inductively coupled plasma mass spectrometry were employed to verify the sample purity, assess how modifications in the synthesis procedure affect the various defects states, and understand how these alterations impact the physical properties. Since the band gap significantly decreased and a relatively narrow visible emissions band was created by these defects, we investigated utilizing these new nZnO for bioimaging applications using traditional fluorescent microscopy techniques. Although most nZnO generally require UV excitation sources to produce emissions, we demonstrate that reducing the band gap allows for a 405 nm laser to sufficiently excite the nanoparticles to detect their emissions during live-cell imaging experiments using a confocal microscope. This work lays the foundation for the use of these new nZnO in various bioimaging applications and enables researchers to investigate the interactions of pure nZnO with cells through fluorescence-based imaging techniques
    corecore