73 research outputs found
Design, fabrication and testing of pyramidal horn antenna
Horn antennas are widely used in areas of wireless communications, electromagnetic sensing, nondestructive testing and evaluation, radio frequency heating and biomedicine. They are also widely used as high gain elements in phased arrays and as feed elements for reflectors and lens antennas in satellite, microwave and millimeter wave systems. Moreover, they serve as a universal standard for calibration and gain measurements of other antennas.An optimum pyramidal horn with gain 20dB and center frequency 9.5GHz is designed. Using the design values two horn antennas are fabricated using aluminum sheets of different thickness namely 1mm and 2mm. The performance parameters like gain, directivity, impedance and s parameters are evaluated. The results are discussed
Assessing observational studies of medical treatments
BACKGROUND: Previous studies have assessed the validity of the observational study design by comparing results of studies using this design to results from randomized controlled trials. The present study examined design features of observational studies that could have influenced these comparisons. METHODS: To find at least 4 observational studies that evaluated the same treatment, we reviewed meta-analyses comparing observational studies and randomized controlled trials for the assessment of medical treatments. Details critical for interpretation of these studies were abstracted and analyzed qualitatively. RESULTS: Individual articles reviewed included 61 observational studies that assessed 10 treatment comparisons evaluated in two studies comparing randomized controlled trials and observational studies. The majority of studies did not report the following information: details of primary and ancillary treatments, outcome definitions, length of follow-up, inclusion/exclusion criteria, patient characteristics relevant to prognosis or treatment response, or assessment of possible confounding. When information was reported, variations in treatment specifics, outcome definition or confounding were identified as possible causes of differences between observational studies and randomized controlled trials, and of heterogeneity in observational studies. CONCLUSION: Reporting of observational studies of medical treatments was often inadequate to compare study designs or allow other meaningful interpretation of results. All observational studies should report details of treatment, outcome assessment, patient characteristics, and confounding assessment
CTCF modulates Estrogen Receptor function through specific chromatin and nuclear matrix interactions
Enhancer regions and transcription start sites of estrogen-target regulated genes are connected by means of Estrogen Receptor long-range chromatin interactions. Yet, the complete molecular mechanisms controlling the transcriptional output of engaged enhancers and subsequent activation of coding genes remain elusive. Here, we report that CTCF binding to enhancer RNAs is enriched when breast cancer cells are stimulated with estrogen. CTCF binding to enhancer regions results in modulation of estrogen-induced gene transcription by preventing Estrogen Receptor chromatin binding and by hindering the formation of additional enhancer-promoter ER looping. Furthermore, the depletion of CTCF facilitates the expression of target genes associated with cell division and increases the rate of breast cancer cell proliferation. We have also uncovered a genomic network connecting loci enriched in cell cycle regulator genes to nuclear lamina that mediates the CTCF function. The nuclear lamina and chromatin interactions are regulated by estrogen-ER. We have observed that the chromatin loops formed when cells are treated with estrogen establish contacts with the nuclear lamina. Once there, the portion of CTCF associated with the nuclear lamina interacts with enhancer regions, limiting the formation of ER loops and the induction of genes present in the loop. Collectively, our results reveal an important, unanticipated interplay between CTCF and nuclear lamina to control the transcription of ER target genes, which has great implications in the rate of growth of breast cancer cells
Differential Developmental Deficits in Retinal Function in the Absence of either Protein Tyrosine Sulfotransferase-1 or -2
To investigate the role(s) of protein-tyrosine sulfation in the retina and to determine the differential role(s) of tyrosylprotein sulfotransferases (TPST) 1 and 2 in vision, retinal function and structure were examined in mice lacking TPST-1 or TPST-2. Despite the normal histologic retinal appearance in both Tpst1−/− and Tpst2−/− mice, retinal function was compromised during early development. However, Tpst1−/− retinas became electrophysiologically normal by postnatal day 90 while Tpst2−/− mice did not functionally normalize with age. Ultrastructurally, the absence of TPST-1 or TPST-2 caused minor reductions in neuronal plexus. These results demonstrate the functional importance of protein-tyrosine sulfation for proper development of the retina and suggest that the different phenotypes resulting from elimination of either TPST-1 or -2 may reflect differential expression patterns or levels of the enzymes. Furthermore, single knock-out mice of either TPST-1 or -2 did not phenocopy mice with double-knockout of both TPSTs, suggesting that the functions of the TPSTs are at least partially redundant, which points to the functional importance of these enzymes in the retina
Supervising Learning Disability in Children through Ayurveda Therapy
Learning Disability (LD) is an invisible disability predictable by a few, afflicting many and causing high degree of impact. Since it has an important bearing on academic function, it carries high degree of distress in the Indian society where failure is offensive. A childhood disorder is written off by difficulty in certain skills such as reading or writing in child with normal intelligence. It can be lifetime conditions that, in some cases, affect many parts of a children's life: school or work, daily routines, family life, and sometimes even friendships and play. In some people, many overlying learning disabilities may be apparent. Other people may have a single, remote learning problem that has little impact on other areas of their lives. This paper illustrates the various types of learning disability, symptoms and the root cause. Various effective Ayurveda treatments for learning disability are proposed here. Aim of this paper is to elaborate the role and benefits of Ayurveda in the society. Now days, Ayurveda is playing an important role both in physical and mental health.
Keywords: Dyslexia, Dyscalculia, Dysgraphia, Auditory Processing Disorders, Visual Processing Disorders, Ayurveda Treatment
Biomimetic synthesis and ultrastructural characterization of a zerovalent gold-hydroxyapatite composite
This manuscript describes one-pot, in situ synthesis of organoapatite-gold nanoparticle composite and its characterization by XRD, energy dispersive X-ray analysis, atomic force, and scanning electron microscopy. This methodology offers a different approach into the synthesis of zerovalent metal-mineral-phase nanocomposites having potential application as osteointegrative ceramics
Sustainability and role conflict: A bibliometric analysis of research themes, trends, and future research directions: 2013-2022
Information Technology (IT) Sector is known for its fast paced and dynamic work environment, which often leads to role conflict among IT professionals. This paper presents a bibliometric analysis and systematic literature review of the phenomenon of role conflict in the IT sector. The study analyses a total 77 academic papers published till 2022, indexed in Scopus and Web of Science database. The bibliometric analysis identifies the most influential authors, journals and keywords related to the topic of role conflict in the IT sector. The systematic literature review identifies and synthesizes the major themes, theoretical perspectives and research method used in the literature on role conflict in the IT sector. The findings suggests that role conflict in the IT sector is a complex phenomenon that can result from a variety of factors including conflicting expectations, unclear job responsibilities, and organisational, and environmental factors that contribute to role conflict, as well as the strategies that can be used to manage and reduce it. The study concludes with recommendations for future research and practical implications for organisations seeking to mitigate the negative effects of role conflict on their employees and performance
Phosphodiester modification by zinc metalated adenine polymer with carboxyl pendants
This report describes a novel carboxyl pendant containing adenylated polymeric template, its metalation with Zn (II), and manifestation of catalytic activity for the hydrolysis of model phosphodiester, bis(p-nitrophenyl) phosphate (bNPP), and plasmid cleavage. Observation of a bell-shaped pH-K<SUB>obs</SUB> profile suggested influence of pH variation over hydrolysis rate. This metalated polymer also afforded facile relaxation of pBR322 supercoiled DNA, with an interesting reusability feature intricately associated with heterogeneous catalysis
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