633 research outputs found

    Analysis of LTE based an Antenna Design for 5G Communications

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    As the world progresses towards the next generation of communications networks, new technological solutions, architectures and standards are urgently required. This evolution of communications networks will facilitate numerous convincing business and consumer applications and speed up large investments in network infrastructure, appliances and devices. Wireless technologies of the last generation, 5G networks, promise an era of all-round, secure and powerful radio network. The use of 5G technology extends beyond traditional telecoms, and includes extremely low latencies, high energy efficiency or comprehensive Gbps. This paper also accurately includes 5G requirements and antenna categorization accompanied by a comparative study of various antenna designs. The various researchers have previously suggested several 5G antenna designs, but an exhaustive examination using their performance improvement system of the various types of 5G antenna has not yet been completed. We thus tried to examine the various types of 5G antenna design, their mechanisms for improving performance, comparisons and possible worldwide breakthroughs

    Synthesis and Spectroscopy of Buckminsterfullerene Cation C<sub>60</sub><sup>+</sup> in a Cryogenic Ion Trapping Instrument

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    The assignment of several diffuse interstellar bands in the near-infrared to C60+ ions present at high abundance in space has renewed interest in the astrochemical importance of fullerenes and analogues. Many of the latter have not been produced in macroscopic quantities, and their spectroscopic properties are not available for comparison with astronomical observations. An apparatus has been constructed that combines laser vaporisation synthesis with spectroscopic characterisation at low temperature in a cryogenic trap. This instrument is used here to record the electronic absorptions of C60+ produced by laser vaporisation of graphite. These are detected by (helium tagged) messenger spectroscopy in a cryogenic trap. By comparison with spectra obtained using a sublimed sample of Buckminsterfullerene, the observed data show that this isomer is the dominant C60+ structure tagged with helium at m/z=724, indicating that the adopted approach can be used to access the spectra of other fullerenes and derivatives of astrochemical interest

    Design of 5G Communication MIMO Based Advanced Antenna System

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    Radio wires are a basic piece of all flexible correspondence structures. Over the most recent five years or something along those lines, the worth of the specific bits of removed receiving wires have been refined to meet the present higher limit necessities. For instance, cross enchanted sending parts feed affiliations, variable stage shifters for electrical down tendency, and etcetera. To this end, how much shows in a base station radio wire have developed comprehensively without loosening up the RF or mechanical nuances of the receiving wires. Throughput is reached out to the client by exploiting MIMO and transporter blend with a high port count radio wire. Plus, a solitary or sets of high port count radio wire can diminish how much radio wires specialties on a pinnacle. In a perfect world, the pinnacle essentials will be remained mindful of by keeping the weight and wind heap of the new receiving wires something practically indistinguishable or not the very receiving wires they remove. Not all high port count radio wire can keep this last liabilit

    Multiple hypersonographic spots in basal cell carcinoma

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    ArticleDERMATOLOGIC SURGERY. 33(10):1215-1219(2007)journal articl

    Pathological activation of KIT in metastatic tumors of acral and mucosal melanomas

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    ArticleINTERNATIONAL JOURNAL OF CANCER. 124(4):862-868 (2009)journal articl

    SLC7A11 Overexpression in Glioblastoma Is Associated with Increased Cancer Stem Cell-Like Properties

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    System x_c^− is a sodium-independent electroneutral transporter, comprising a catalytic subunit xCT (SLC7A11), which is involved in importing cystine. Certain cancers such as gliomas upregulate the expression of system x_c^−, which confers a survival advantage against the detrimental effects of reactive oxygen species (ROS) by increasing generation of the antioxidant glutathione. However, ROS have also been shown to function as targeted, intracellular second messengers in an array of physiological processes such as proliferation. Several studies have implicated ROS in important cancer features such as migration, invasion, and contribution to a cancer stem cell (CSC)-like phenotype. The role of system x_c^− in regulating these ROS-sensitive processes in glioblastoma multiforme (GBM), the most aggressive malignant primary brain tumor in adults, remains unknown. Stable SLC7A11 knockdown and overexpressing U251 glioma cells were generated and characterized to understand the role of redox and system x_c^− in glioma progression. SLC7A11 knockdown resulted in higher endogenous ROS levels and enhanced invasive properties. On the contrary, overexpression of SLC7A11 resulted in decreased endogenous ROS levels as well as decreased migration and invasion. However, SLC7A11-overexpressing cells displayed actin cytoskeleton changes reminiscent of epithelial-like cells and exhibited an increased CSC-like phenotype. The enhanced CSC-like phenotype may contribute to increased chemoresistance and suggests that overexpression of SLC7A11 in the context of GBM may contribute to tumor progression. These findings have important implications for cancer management where targeting system x_C^− in combination with other chemotherapeutics can reduce cancer resistance and recurrence and improve GBM patient survival

    Black holes and a scalar field in an expanding universe

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    We consider a model of an inhomogeneous universe including a massless scalar field, where the inhomogeneity is assumed to consist of many black holes. This model can be constructed by following Lindquist and Wheeler, which has already been investigated without including scalar field to show that an averaged scale factor coincides with that of the Friedmann model. In this work we construct the inhomogeneous universe with an massless scalar field, where we assume that the averaged scale factor and scalar field are given by those of the Friedmann model including a scalar field. All of our calculations are carried out in the framework of Brans-Dicke gravity. In constructing the model of an inhomogeneous universe, we define the mass of a black hole in the Brans-Dicke expanding universe which is equivalent to ADM mass if the mass evolves adiabatically, and obtain an equation relating our mass to the averaged scalar field and scale factor. As the results we find that the mass has an adiabatic time dependence in a sufficiently late stage of the expansion of the universe, and that the time dependence is qualitatively diffenrent according to the sign of the curvature of the universe: the mass increases decelerating in the closed universe case, is constant in the flat case and decreases decelerating in the open case. It is also noted that the mass in the Einstein frame depends on time. Our results that the mass has a time dependence should be retained even in the general scalar-tensor gravitiy with a scalar field potential. Furthermore, we discuss the relation of our results to the uniqueness theorem of black hole spacetime and gravitational memory effect.Comment: 16 pages, 3 tables, 5 figure
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