1,342 research outputs found
Multiple Antenna Techniques for Terahertz Nano-Bio Communication
Using higher frequency bands becomes an essential demand resulting from the explosive wireless traffic needs and the spectrum shortage of the currently used bands. This paper presents an overview on the terahertz technology and its application in the area of multi-input multi-output antenna system and in-vivo nano-communication. In addition, it presents a preliminary study on applying multiple input-single output (MISO) antenna technique to investigate the signal propagation and antenna diversity techniques inside the human skin tissues, which is represented by three layers: stratum corneum (SC), epidermis, and dermis layers, in the terahertz (THz) frequency range (0.8-1.2) THz. The spatial antenna diversity is investigated in this study to understand MISO system performance for two different in-vivo channels resulting from the signal propagation between two transmitting antennas, located at the dermis layer, and one receiving antenna, located at epidermis layer. Three techniques are investigated: selection combining (SC), equal-gain combing (EGC), and maximum-ratio combining (MRC). The initial study indicates that using multiple antenna technique with THz might be not useful for in-vivo nano-communication
Concert recording 2016-01-29
[Track 01]. Impromptu no. 1 in F major, op. 78, no. 1 / S. Coleridge Taylor -- [Track 02]. Go down Moses / Fela Sowande -- [Track 03]. Retrospection / Florence B. Price -- [Track 04]. Suite for organ, violin and violoncello. Theme and variation / Josef Rheinberger -- [Track 05]. Improvisation on We shall overcome / arranged by Carl Haywood
Multiwavelength studies of G298.60.0: An old GeV supernova remnant interacting with molecular clouds
Hadronic -ray sources associated with supernova remnants (SNRs) can
serve as stopwatches for the escape of cosmic rays from SNRs, which gradually
develops from highest-energy particles to lowest-energy particles with time. In
this work, we analyze the 13.7~yr \emph{Fermi}-LAT data to investigate the
-ray feature in/around the SNR G298.60.0 region. With -ray
spatial analyses, we detect three point-like components. Among them, Src-NE is
at the eastern SNR shell, and Src-NW is adjacent to the western edge of this
SNR. Src-NE and Src-NW demonstrate spectral breaks at energies around/below
1.8~GeV, suggesting an old SNR age of 10~kyr. We also look into the X-ray
emission from the G298.60.0 region, with the Chandra-ACIS data. We detected
an extended keV source having a centrally filled structure inside the radio
shell. The X-ray spectra are well fit by a model which assumes a collisional
ionisation equilibrium of the thermal plasma, further supporting an old SNR
age. Based on our analyses of the NANTEN CO- and ATCA-Parkes HI-line data, we
determined a kinematic distance of 10.1~kpc from us to G298.60.0. This
distance entails a large physical radius of the SNR of 15.5~pc, which is
an additional evidence for an old age of 10~kyr. Besides, the CO data cube
enables us to three-dimensionally locate the molecular clouds (MCs) which are
potentially interacting with SNR G298.60.0 and could account for the
hadronic -rays detected at Src-NE or Src-NW. Furthermore, the
multiwavelength observational properties unanimously imply that the SNR--MC
interaction occurs mainly in the northeast direction.Comment: Accepted by Publications of the Astronomical Society of Japan (PASJ)
on 16-Jan-202
Intestinal Microbiota and Lymphoma
The intestinal microbiota and gut immune system must constantly communicate to maintain a balance between tolerance and activation: on one hand, our immune system should protect us from pathogenic microbes and on the other hand, most of the millions of microbes in and on our body are innocuous symbionts and some can even be beneficial. Since there is such a close interaction between the immune system and the intestinal microbiota, it is not surprising that some lymphomas such as mucosal-associated lymphoid tissue (MALT) lymphoma have been shown to be caused by the presence of certain bacteria. Animal models played an important role in establishing causation and mechanism of bacteria-induced MALT lymphoma. In this review we discuss different ways that animal models have been applied to establish a link between the gut microbiota and lymphoma and how animal models have helped to elucidate mechanisms of microbiota-induced lymphoma. While there are not a plethora of studies demonstrating a connection between microbiota and lymphoma development, we believe that animal models are a system which can be exploited in the future to enhance our understanding of causation and improve prognosis and treatment of lymphoma
Cytogenetic Estimation of Broccoli Extract on Dexamethasone Treated Mice
The current study was intended to evaluate the active compounds found in hydro-alcoholic extract of Brassica oleracea var. italica(broccoli), also to estimates the percentage of chromosomal aberrations (CAs) ,mitotic index (MI) and micronuclei (MN) formation in mouse bone marrow cells .The mice were divided into, negative group received (0.2 ml of Distilled Water)intraperitoneally ,positive group I was given single dose of dexamethasone (0.4 mg/kg for 24 h) and positive group II (acute toxicity assay) administrated with (0.2 ml) of high level dose (800 mg/kg) of extract for 5 days. Interaction groups treated with different doses of extract (50,100,200,400 and 600 mg/kg) for 5 days in addition to a single ( 0.4 mg/kg) of dexamethasone per each dose of extract. High level dose (800mg/kg) of broccoli extract had show null genotoxicity for bone marrow cells of mouse. Dexamethasone showed significant effects (P< 0.05) in reducing mitotic index and increased chromosomal aberrations and micronuclei in mouse bone marrow cells (in vivo). Broccoli extract significantly increased MI and reduced (CA ,MN) (P< 0.05) especially at does (400 mg/kg). Keywords- mitotic index, Micronuclei formation ,Chromosomal aberrations , Dexamethasone, Brassica oleracea var. italica (broccoli), hydro-alcoholic extract
FPGA implementation of LDPC soft-decision decoders based DCSK for spread spectrum applications
Spread spectrum (SS) communications have attracted interest because of their channel attenuation immunity and low intercept potential. Apart from some extra features such as basic transceiver structures, chaotic communication would be the analog alternative to digital SS systems. Differential chaos shift keying (DCSK) systems, non-periodic and random characteristics among chaos carriers as well as their interaction with soft data are designed based on low-density parity-check (LDPC) codes in this brief. Because of simple structure, and glorious ability to correct errors. Using the Xilinx kintex7 FPGA development kit, we investigate the hardware performance and resource requirement tendencies of the DCSK communication system based on LDPC decoding algorithms (Prob. Domain, Log Domain and Min-Sum) over AWGN channel. The results indicate that the proposed system model has substantial improvements in the performance of the bit error rate (BER) and the real-time process. The Min-Sum decoder has relatively fewer FPGA resources than the other decoders. The implemented system will achieve 10-4 BER efficiency with 5 dB associate Eb/No as a coding gain
Value of “large FOV” calcium score as a screening method for detection of extracardiac incidental findings
AbstractPurposeThe purpose of this study was to emphasize the value of calcium scoring (Ca score) using a large field of view (“large FOV”) as a screening method for detection of extracardiac incidental findings.Materials and methods64-Multislice CT angiography using a “large FOV” in the preliminary calcium score followed by the post-contrast routine “small FOV” examination was performed for 382 consecutive patients between January 2011 and December 2012.Results375 Patients (203 men and 172 women) with age range between 40 and 80years (mean, 60years), were studied, using a “large FOV” technique. Among whole incidental extracardiac findings, “significant” extracardiac abnormalities (emergent and intermediate findings) were detected in 24.8% of cases, among which 13.6% would have been missed if only using a “small FOV” technique.ConclusionResults showed that using Ca score with a “large FOV” is favorable for better, accurate and more frequent detection of extracardiac incidental findings. With usage of low dose technique, the difference in dose between “small FOV” and “large FOV” techniques is justified for detection of supplementary “significant” extra-cardiac findings including serious findings such as lung cancer or metastatic deposits
Chandra Observations of A Galactic Supernova Remnant Vela Jr.: A New Sample of Thin Filaments Emitting Synchrotron X-Rays
A galactic supernova remnant (SNR) Vela Jr. (RX J0852.04622, G266.61.2)
shows sharp filamentary structure on the north-western edge of the remnant in
the hard X-ray band. The filaments are so smooth and located on the most outer
side of the remnant. We measured the averaged scale width of the filaments
( and ) with excellent spatial resolution of {\it Chandra}, which are
in the order of the size of the point spread function of {\it Chandra} on the
upstream side and 49.5 (36.0--88.8) arcsec on the downstream side,
respectively. The spectra of the filaments are very hard and have no line-like
structure, and were well reproduced with an absorbed power-law model with
2.67 (2.55--2.77), or a {\tt SRCUT} model with = 4.3
(3.4--5.3) Hz under the assumption of . These results
imply that the hard X-rays are synchrotron radiation emitted by accelerated
electrons, as mentioned previously. Using a correlation between a function
and the SNR age, we estimated the
distance and the age of Vela Jr.: the estimated distance and age are 0.33
(0.26--0.50) kpc and 660 (420--1400) years, respectively. These results are
consistent with previous reports, implying that --age relation may be
a useful tool to estimate the distance and the age of synchrotron X-ray
emitting SNRs.Comment: 19 pages, 8 figures, ApJ, in pres
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