1,337 research outputs found
Superpositions of the dual family of nonlinear coherent states and their non-classical properties
Nonlinear coherent states (CSs) and their {\it dual families} were introduced
recently. In this paper we want to obtain their superposition and investigate
their non-classical properties such as antibunching effect, quadrature
squeezing and amplitude squared squeezing. For this purpose two types of
superposition are considered. In the first type we neglect the normalization
factors of the two components of the dual pair, superpose them and then we
normalize the obtained states, while in the second type we superpose the two
normalized components and then again normalize the resultant states. As a
physical realization, the formalism will then be applied to a special physical
system with known nonlinearity function, i.e., Hydrogen-like spectrum. We
continue with the (first type of) superposition of the dual pair of
Gazeau-Klauder coherent states (GKCSs) as temporally stable CSs. An application
of the proposal will be given by employing the P\"oschl-Teller potential
system. The numerical results are presented and discussed in detail, showing
the effects of this special quantum interference.Comment: 19 pages, 18 figures, Accpeted for Publication in Optics
Communications, 201
Terahertz Channel Characterization Inside the Human Skin for Nano-Scale Body-Centric Networks
This paper focuses on the development of a novel radio channel model inside the human skin at the terahertz range, which will enable the interaction among potential nano-machines operating in the inter cellular areas of the human skin. Thorough studies are performed on the attenuation of electromagnetic waves inside the human skin, while taking into account the frequency of operation, distance between the nano-machines and number of sweat ducts. A novel channel model is presented for communication of nano-machines inside the human skin and its validation is performed by varying the aforementioned parameters with a reasonable accuracy. The statistics of error prediction between simulated and modeled data are: mean (μ)= 0.6 dB and standard deviation (σ)= 0.4 dB, which indicates the high accuracy of the prediction model as compared with measurement data from simulation. In addition, the results of proposed channel model are compared with terhaertz time-domain spectroscopy based measurement of skin sample and the statistics of error prediction in this case are: μ = 2.10 dB and σ = 6.23 dB, which also validates the accuracy of proposed model. Results in this paper highlight the issues and related challenges while characterizing the communication in such a medium, thus paving the way towards novel research activities devoted to the design and the optimization of advanced applications in the healthcare domain
Terahertz Channel Characterisation Inside the Human Skin for Nano-scale Body-Centric Networks
Ellipticity Statistics of Ultra Wideband MIMO Channels for Body Centric Wireless Communication
In this paper, ellipticity statistics of 2 × 2 ultra wideband multiple-input-multiple-output (MIMO) channel for body-centric wireless communication is evaluated by quantifying four different on body links namely; waist-back, waist-chest, waist-ankle and waist-wrist. Results show that at lower values of signal to noise (SNR), spatial multiplexing dependent capacity degrades as the eigen value dispersion decreases (i.e., lower ellipticity statistic), whereas it increases at higher values of SNR
Complete Study of an Original Power-Exponential Transformation Approach for Generalizing Probability Distributions
In this paper, we propose a flexible and general family of distributions based on an original power-exponential transformation approach. We call it the modified generalized-G (MGG) family. The elegance and significance of this family lie in the ability to modify the standard distributions by changing their functional forms without adding new parameters, by compounding two distributions, or by adding one or two shape parameters. The aim of this modification is to provide flexible shapes for the corresponding probability functions. In particular, the distributions of the MGG family can possess increasing, constant, decreasing, “unimodal”, or “bathtub-shaped“ hazard rate functions, which are ideal for fitting several real data sets encountered in applied fields. Some members of the MGG family are proposed for special distributions. Following that, the uniform distribution is chosen as a baseline distribution to yield the modified uniform (MU) distribution with the goal of efficiently modeling measures with bounded values. Some useful key properties of the MU distribution are determined. The estimation of the unknown parameters of the MU model is discussed using seven methods, and then, a simulation study is carried out to explore the performance of the estimates. The flexibility of this model is illustrated by the analysis of two real-life data sets. When compared to fair and well-known competitor models in contemporary literature, better-fitting results are obtained for the new model
Comprehensive mechanism of gene silencing and its role in plant growth and development
Gene silencing is a negative feedback mechanism that regulates gene expression to define cell fate and also regulates metabolism and gene expression throughout the life of an organism. In plants, gene silencing occurs via transcriptional gene silencing (TGS) and post-transcriptional gene silencing (PTGS). TGS obscures transcription via the methylation of 5′ untranslated region (5′UTR), whereas PTGS causes the methylation of a coding region to result in transcript degradation. In this review, we summarized the history and molecular mechanisms of gene silencing and underlined its specific role in plant growth and crop production
A theoretical scheme for generation of Gazeau-Klauder coherent states via intensity-dependent degenerate Raman interaction
A theoretical scheme is presented for generating Gazeau-Klauder coherent
states(GKCSs) via the generalization of degenerate Raman interaction with
coupling constant to intensity-dependent coupling. Firstly, we prove that in
the intensity-dependent degenerate Raman interaction, under particular
conditions, the modified efective Hamiltonian can be used instead of
Hamiltonian in the interaction picture, for describing the atom-field
interaction. We suppose that the cavity field is initially prepared in a
nonlinear CS, which is not temporally stable. As we will observe, after the
occurrence of the interaction between atom and field, the generated state
involves a superposition of GKCSs which are temporally stable and initial
nonlinear CS. Under specific conditions which may be prepared, the generated
state just includes GKCS. So, in this way we produced the GKCS, successfully.Comment: 12 pages, 1 figures, Optics Communications, Article in Pres
Influences of COVID-19 Pandemic Lockdown on Excess Lifetime Cancer Risk Value of Natural Radiation
Abstract: This study focuses on the consequences of the COVID-19 pandemic on annual effective doses and excess lifetime cancer risk values due to ionizing radiation and radon which has been reported UNSCEAR 2000. The random data collection questionnaire method was applied to assess the indoor and outdoor occupancy factor for three age groups during the epidemic in Turkey. The results indicated age group C (Age > 65 y) has more influence from pandemic indoor and outdoor occupancy factor. As compared to before pandemic data in study area and global average exposure to natural radioactive sources. Graphic abstract: [Figure not available: see fulltext.] © 2021, Akadémiai Kiadó, Budapest, Hungary.This research was supported by Project No (TURSP-2020/45) Taif University, Saudi Arabia. Also, the authors are grateful to the University of Kyrenia research group for the use of their facilities
Chemical composition and pharmacological bio-efficacy of Parrotiopsis jacquemontiana (Decne) Rehder for anticancer activity
Consistent STAT3 (Single transducer and activator of transcription 3) activation is observed in many tumors and promotes malignant cell transformation. In the present investigation, we evaluated the anticancer effects of Parrotiopsis jacquemontiana methanol fraction (PJM) on STAT3 inhibition in HCCLM3 and MDA-MB 231 cells. PJM suppressed the activation of upstream kinases i.e. JAK-1/2 (Janus kinase-1/2), and c-Src (Proto-oncogene tyrosine-protein kinase c-Src), and upregulated the expression levels of PIAS-1/3 (Protein Inhibitor of Activated STATs-1/3), SHP-1/2 (Src-homology region 2 domain-containing phosphatase-1/2), and PTP-1β (Protein tyrosine phosphatase 1 β) which negatively regulate STAT3 signaling pathway. PJM also decreased the levels of protein products conferring to various oncogenes, which in turn repressed the proliferation, migration, invasion, and induced apoptosis in cancer cell lines. The growth inhibitory effects of PJM on cell-cycle and metastasis were correlated with decreased expression levels of CyclinD1, CyclinE, MMP-2 (Matrix metalloproteinases-2), and MMP-9 (Matrix metalloproteinases-9). Induction of apoptosis was indicated by the cleavage and subsequent activation of Caspases (Cysteine-dependent Aspartate-directed Proteases) i.e. caspase-3, 7, 8, 9, and PARP (Poly (ADP-ribose) polymerase) as well as through the down-regulation of anti-apoptotic proteins. These apoptotic effects of PJM were preceded by inhibition of STAT3 cell-signaling pathway. STAT3 was needed for PJM-induced apoptosis, and inhibition of STAT3 via pharmacological inhibitor (Stattic; SC-203282) abolished the apoptotic effects. Conclusively, our results demonstrate the capability of PJM to inhibit cancer cell-proliferation and induce apoptosis by suppressing STAT3 via upregulation of STAT3 inhibitors and pro-apoptotic proteins whereas the down-regulation of upstream kinases and anti-apoptotic protein expression. In future, one-step advance studies of PHM regarding its role in metastatic inhibition, immune response modulation for reducing tumor, and inducing apoptosis in suitable animal models would be an interesting and promising research area
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