4,717 research outputs found

    Phonon arithmetic in a trapped ion system

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    Single-quantum level operations are important tools to manipulate a quantum state. Annihilation or creation of single particles translates a quantum state to another by adding or subtracting a particle, depending on how many are already in the given state. The operations are probabilistic and the success rate has yet been low in their experimental realization. Here we experimentally demonstrate (near) deterministic addition and subtraction of a bosonic particle, in particular a phonon of ionic motion in a harmonic potential. We realize the operations by coupling phonons to an auxiliary two-level system and applying transitionless adiabatic passage. We show handy repetition of the operations on various initial states and demonstrate by the reconstruction of the density matrices that the operations preserve coherences. We observe the transformation of a classical state to a highly non-classical one and a Gaussian state to a non-Gaussian one by applying a sequence of operations deterministically

    Salt stress induced ion accumulation, ion homeostasis, membrane injury and sugar contents in salt-sensitive rice (Oryza sativa L. spp. indica) roots under isoosmotic conditions

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    Excess salt induced ionic and osmotic stresses that disturbed metabolism and led to reduction of plant development. Previous studies reported that sugars in stressed plants were involved in stress tolerance. However, the role of sugars in salt-stressed plants against only ionic effects is still unclear. The objective of this research was to investigate accumulation and homeostasis of ions, membrane injury, water content, growth characters and sugar contents in roots, in-response to salt stress under iso-osmotic conditions. Salt-sensitive rice, Pathumthani1 (PT1) was grown on MS culture medium for 7 days and was adjusted to salt stress under iso-osmotic conditions (-1.75 ± 0.20 MPa) by mannitol for 4 days. An increase in NaCl increased Na+ and Na+:K+ in PT1 roots leading to increased membrane injury, while the water content was decreased. Additionally, growth characters, including number, length, fresh weight and dry weight of roots, were inhibited. Sugar accumulations in PT1 roots were enhanced by increases in NaCl. The increase in Na+ was positively related to total soluble sugars, resulting in an osmotic adjustment of the membrane that maintained water availability. The accumulation of sugars in PT1 roots may be a primary salt-defense mechanism and may function as an osmotic control.Key words: Mannitol, membrane injury, oligosaccharides, sodium ion, potassium ion, sodium chloride

    Investigating the association of rs2910164 with cancer predisposition in an Irish cohort.

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    IntroductionMicroRNAs (miRNAs) are small noncoding RNA molecules that exert post-transcriptional effects on gene expression by binding with cis-regulatory regions in target messenger RNA (mRNA). Polymorphisms in genes encoding miRNAs or in miRNA-mRNA binding sites confer deleterious epigenetic effects on cancer risk. miR-146a has a role in inflammation and may have a role as a tumour suppressor. The polymorphism rs2910164 in the MIR146A gene encoding pre-miR-146a has been implicated in several inflammatory pathologies, including cancers of the breast and thyroid, although evidence for the associations has been conflicting in different populations. We aimed to further investigate the association of this variant with these two cancers in an Irish cohort.MethodsThe study group comprised patients with breast cancer (BC), patients with differentiated thyroid cancer (DTC) and unaffected controls. Germline DNA was extracted from blood or from saliva collected using the DNA Genotek Oragene 575 collection kit, using crystallisation precipitation, and genotyped using TaqMan-based PCR. Data were analysed using SPSS, v22.ResultsThe total study group included 1516 participants. This comprised 1386 Irish participants; 724 unaffected individuals (controls), 523 patients with breast cancer (BC), 136 patients with differentiated thyroid cancer (DTC) and three patients with dual primary breast and thyroid cancer. An additional cohort of 130 patients with DTC from the South of France was also genotyped for the variant. The variant was detected with a minor allele frequency (MAF) of 0.19 in controls, 0.22 in BC and 0.27 and 0.26 in DTC cases from Ireland and France, respectively. The variant was not significantly associated with BC (per allele odds ratio = 1.20 (0.98-1.46), P  = 0.07), but was associated with DTC in Irish patients (per allele OR = 1.59 (1.18-2.14), P = 0.002).ConclusionThe rs2910164 variant in MIR146A is significantly associated with DTC, but is not significantly associated with BC in this cohort

    Prevalence of Medical Disorders in Pregnancy in Ebonyi State University Teaching Hospital

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    Background: Pregnancy is a physiological state, but when associated with an underlying medical disorder, it has a large impact on the well‑being of a mother. The pattern of medical disorders has been documented to have changed over the years.Aim: This study seeks to retrospectively determine the incidence of medical disorders in pregnancy, and to determine the trend over a 5‑year period in Ebonyi State University Teaching Hospital (EBSUTH).Materials and Methods: This was a retrospective study of all medical cases in pregnancy managed in EBSUTH from 1st of January 2006 to 31st December 2010. Data were analyzed using Epi‑Info statistical package. The results were presented in simple tables. Test statistics was set at 95% confidence interval. Results: A total of 339 medical cases in pregnancy of 2117 admissions were managed during the study period (16.0%). Mean (SD) age of the women was 28.05 (5.36) years and age ranged 15‑45 years for about 314 cases that had the age documented. Of the 339 cases, a total of 149 cases of malaria occurred during the study period (149/339; 44%), out of which only 104 were malaria alone. The rest (45 in number) occurred with urinary tract infection, pregnancy‑induced hypertension, Diabetes mellitus, lobar pneumonia, and anemia in pregnancy. This was followed by hypertensive disorders which account for 29.2% of all cases of medical disorders. Urinary tract infection ranked third (20.7% of all medical disorder). The incidence of malaria was 7% (149/2117), that of hypertensive disorder was 4.7% (99/2117), and of Urinary Tract Infection was 3.1% (65/2117). Others include anemia in pregnancy 0.6% (13/2117), Diabetes mellitus 0.4% (9/2117), and Gastroenteritis 0.4% (9/2117). There is no statistical differencebetween the incidences of medical complications over the study period.Conclusion: There is relatively little change in the incidences of medical complication over the studied period. Malaria played a very important role in the prevalence of medical complications in pregnancy. Preventive strategies may have reduced the prevalence over the years. However, more effort is needed to markedly reduce the medical complications in pregnancy.  Keywords: Disorders, medical complication, pregnancy, prevalence, tren

    Towards video streaming in IoT environments: vehicular communication perspective

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    Multimedia oriented Internet of Things (IoT) enables pervasive and real-time communication of video, audio and image data among devices in an immediate surroundings. Today's vehicles have the capability of supporting real time multimedia acquisition. Vehicles with high illuminating infrared cameras and customized sensors can communicate with other on-road devices using dedicated short-range communication (DSRC) and 5G enabled communication technologies. Real time incidence of both urban and highway vehicular traffic environment can be captured and transmitted using vehicle-to-vehicle and vehicle-to-infrastructure communication modes. Video streaming in vehicular IoT (VSV-IoT) environments is in growing stage with several challenges that need to be addressed ranging from limited resources in IoT devices, intermittent connection in vehicular networks, heterogeneous devices, dynamism and scalability in video encoding, bandwidth underutilization in video delivery, and attaining application-precise quality of service in video streaming. In this context, this paper presents a comprehensive review on video streaming in IoT environments focusing on vehicular communication perspective. Specifically, significance of video streaming in vehicular IoT environments is highlighted focusing on integration of vehicular communication with 5G enabled IoT technologies, and smart city oriented application areas for VSV-IoT. A taxonomy is presented for the classification of related literature on video streaming in vehicular network environments. Following the taxonomy, critical review of literature is performed focusing on major functional model, strengths and weaknesses. Metrics for video streaming in vehicular IoT environments are derived and comparatively analyzed in terms of their usage and evaluation capabilities. Open research challenges in VSV-IoT are identified as future directions of research in the area. The survey would benefit both IoT and vehicle industry practitioners and researchers, in terms of augmenting understanding of vehicular video streaming and its IoT related trends and issues

    Hexagonal Boron Nitride-Enhanced Optically Transparent Polymer Dielectric Inks for Printable Electronics.

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    Solution-processable thin-film dielectrics represent an important material family for large-area, fully-printed electronics. Yet, in recent years, it has seen only limited development, and has mostly remained confined to pure polymers. Although it is possible to achieve excellent printability, these polymers have low (≈2-5) dielectric constants (ε r ). There have been recent attempts to use solution-processed 2D hexagonal boron nitride (h-BN) as an alternative. However, the deposited h-BN flakes create porous thin-films, compromising their mechanical integrity, substrate adhesion, and susceptibility to moisture. These challenges are addressed by developing a "one-pot" formulation of polyurethane (PU)-based inks with h-BN nano-fillers. The approach enables coating of pinhole-free, flexible PU+h-BN dielectric thin-films. The h-BN dispersion concentration is optimized with respect to exfoliation yield, optical transparency, and thin-film uniformity. A maximum ε r ≈ 7.57 is achieved, a two-fold increase over pure PU, with only 0.7 vol% h-BN in the dielectric thin-film. A high optical transparency of ≈78.0% (≈0.65% variation) is measured across a 25 cm2 area for a 10 μm thick dielectric. The dielectric property of the composite is also consistent, with a measured areal capacitance variation of <8% across 64 printed capacitors. The formulation represents an optically transparent, flexible thin-film, with enhanced dielectric constant for printed electronics.EPSRC funding acknowledged (EP/L016087/1

    Coherent states and uncertainty relations for the damped harmonic oscillator with time-dependent frequency

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    Starting with evaluations of propagator and wave function for the damped harmonic oscillator with time-dependent frequency, exact coherent states are constructed. These coherent states satisfy the properties which coherent states should generally have

    Secrecy Results for Compound Wiretap Channels

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    We derive a lower bound on the secrecy capacity of the compound wiretap channel with channel state information at the transmitter which matches the general upper bound on the secrecy capacity of general compound wiretap channels given by Liang et al. and thus establishing a full coding theorem in this case. We achieve this with a stronger secrecy criterion and the maximum error probability criterion, and with a decoder that is robust against the effect of randomisation in the encoding. This relieves us from the need of decoding the randomisation parameter which is in general not possible within this model. Moreover we prove a lower bound on the secrecy capacity of the compound wiretap channel without channel state information and derive a multi-letter expression for the capacity in this communication scenario.Comment: 25 pages, 1 figure. Accepted for publication in the journal "Problems of Information Transmission". Some of the results were presented at the ITW 2011 Paraty [arXiv:1103.0135] and published in the conference paper available at the IEEE Xplor
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