845 research outputs found

    TCR deep sequencing of transgenic RAG-1-deficient mice reveals endogenous TCR recombination: a cause for caution

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    The utility of T‐cell receptor (TCR) transgenic mice in medical research has been considerable, with applications ranging from basic biology all the way to translational and clinical investigations. Crossing of TCR transgenic mice with either recombination‐activating gene (RAG)‐1 or RAG‐2 knockouts is frequently used to generate mice with a monoclonal T‐cell repertoire. However, low level productive TCR rearrangement has been reported in RAG‐deficient mice expressing transgenic TCRs. Using deep sequencing, we set out to directly examine and quantify the presence of these endogenous TCRs. Our demonstration that functional nontransgenic TCRs are present in nonmanipulated mice has wide reaching ramifications worthy of critical consideration

    Chromium Remediation or Release? Effect of Iron(II) Sulfate Addition on Chromium(VI) Leaching from Columns of Chromite Ore Processing Residue

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    Chromite ore processing residue (COPR), derived from the so-called high lime processing of chromite ore, contains high levels of Cr(III) and Cr(VI) and has a pH between 11 and 12. Ferrous sulfate, which is used for remediation of Cr(VI) contamination in wastewater and soils via reduction to Cr(III) and subsequent precipitation of iron(III)/chromium- (III) hydroxide, has also been proposed for remediation of Cr(VI) in COPR. Instead, however, addition of FeSO4 to the infiltrating solution in column experiments with COPR greatly increased leaching of Cr(VI). Leached Cr(VI) increased from 3.8 to 12.3 mmol kg-1 COPR in 25 pore volumes with 20 mM FeSO4, reaching solution concentrations as high as 1.6 mM. Fe(II) was ineffective in reducing Cr(VI) to Cr(III) because it precipitated when it entered the column due to the high pH of COPR, while Cr(VI) in solution was transported away with the infiltrating solution. The large increase in leaching of Cr(VI) upon infiltration of sulfate, either as FeSO4 or Na2SO4, was caused by anion exchange of sulfate for chromate in the layered double hydroxide mineral hydrocalumite, a process for which scanning electron microscopy with energy-dispersive X-ray microanalysis provided direct evidence

    Standard Neutrino Spectrum from B-8 Decay

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    We present a systematic evaluation of the shape of the neutrino energy spectrum produced by beta-decay of 8^8B. We place special emphasis on determining the range of uncertainties permitted by existing laboratory data and theoretical ingredients (such as forbidden and radiative corrections). We review and compare the available experimental data on the 8^8B(ÎČ+)8(\beta^+){}^8Be(2α)(2\alpha) decay chain. We analyze the theoretical and experimental uncertainties quantitatively. We give a numerical representation of the best-fit (standard-model) neutrino spectrum, as well as two extreme deviations from the standard spectrum that represent the total (experimental and theoretical) effective ±3σ\pm3\sigma deviations. Solar neutrino experiments that are currently being developed will be able to measure the shape of the 8^8B neutrino spectrum above about 5 MeV. An observed distortion of the 8^8B solar neutrino spectrum outside the range given in the present work could be considered as evidence, at an effective significance level greater than three standard deviations, for physics beyond the standard electroweak model. We use the most recent available experimental data on the Gamow--Teller strengths in the A=37A=37 system to calculate the 8^8B neutrino absorption cross section on chlorine: σCl=(1.14±0.11)×10−42\sigma_{\rm Cl}=(1.14\pm0.11)\times10^{-42}~cm2^2 (±3σ\pm3\sigma errors). The chlorine cross section is also given as a function of the neutrino energy. The 8^8B neutrino absorption cross section in gallium is σGa=(2.46−1.1+2.1)×10−42\sigma_{\rm Ga}=(2.46^{+2.1}_{-1.1})\times10^{-42} cm2^2 (±3σ\pm3\sigma errors).Comment: Revised version, to appear in Phys. Rev.

    Use of low-dose oral theophylline as an adjunct to inhaled corticosteroids in preventing exacerbations of chronic obstructive pulmonary disease: study protocol for a randomised controlled trial.

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    BACKGROUND: Chronic obstructive pulmonary disease (COPD) is associated with high morbidity, mortality, and health-care costs. An incomplete response to the anti-inflammatory effects of inhaled corticosteroids is present in COPD. Preclinical work indicates that 'low dose' theophylline improves steroid responsiveness. The Theophylline With Inhaled Corticosteroids (TWICS) trial investigates whether the addition of 'low dose' theophylline to inhaled corticosteroids has clinical and cost-effective benefits in COPD. METHOD/DESIGN: TWICS is a randomised double-blind placebo-controlled trial conducted in primary and secondary care sites in the UK. The inclusion criteria are the following: an established predominant respiratory diagnosis of COPD (post-bronchodilator forced expiratory volume in first second/forced vital capacity [FEV1/FVC] of less than 0.7), age of at least 40 years, smoking history of at least 10 pack-years, current inhaled corticosteroid use, and history of at least two exacerbations requiring treatment with antibiotics or oral corticosteroids in the previous year. A computerised randomisation system will stratify 1424 participants by region and recruitment setting (primary and secondary) and then randomly assign with equal probability to intervention or control arms. Participants will receive either 'low dose' theophylline (Uniphyllin MR 200 mg tablets) or placebo for 52 weeks. Dosing is based on pharmacokinetic modelling to achieve a steady-state serum theophylline of 1-5 mg/l. A dose of theophylline MR 200 mg once daily (or placebo once daily) will be taken by participants who do not smoke or participants who smoke but have an ideal body weight (IBW) of not more than 60 kg. A dose of theophylline MR 200 mg twice daily (or placebo twice daily) will be taken by participants who smoke and have an IBW of more than 60 kg. Participants will be reviewed at recruitment and after 6 and 12 months. The primary outcome is the total number of participant-reported COPD exacerbations requiring oral corticosteroids or antibiotics during the 52-week treatment period. DISCUSSION: The demonstration that 'low dose' theophylline increases the efficacy of inhaled corticosteroids in COPD by reducing the incidence of exacerbations is relevant not only to patients and clinicians but also to health-care providers, both in the UK and globally. TRIAL REGISTRATION: Current Controlled Trials ISRCTN27066620 was registered on Sept. 19, 2013, and the first subject was randomly assigned on Feb. 6, 2014

    Joint diffraction and modeling approach to the structure of liquid alumina

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    The structure of liquid alumina at a temperature ∌2400 K near its melting point was measured using neutron and high-energy x-ray diffraction by employing containerless aerodynamic–levitation and laser-heating techniques. The measured diffraction patterns were compared to those calculated from molecular dynamics simulations using a variety of pair potentials, and the model found to be in best agreement with experiments was refined using the reverse Monte Carlo method. The resultant model shows that the melt is composed predominantly of AlO4 and AlO5 units, in the approximate ratio of 2:1, with only minor fractions of AlO3 and AlO6 units. The majority of Al-O-Al connections involve corner-sharing polyhedra (83%), although a significant minority involve edge-sharing polyhedra (16%), predominantly between AlO5 and either AlO5 or AlO4 units. Most of the oxygen atoms (81%) are shared among three or more polyhedra, and the majority of these oxygen atoms are triply shared among one or two AlO4 units and two or one AlO5 units, consistent with the abundance of these polyhedra in the melt and their fairly uniform spatial distribution

    Systematic review of communication technologies to promote access and engagement of young people with diabetes into healthcare

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    Background: Research has investigated whether communication technologies (e.g. mobile telephony, forums, email) can be used to transfer digital information between healthcare professionals and young people who live with diabetes. The systematic review evaluates the effectiveness and impact of these technologies on communication. Methods: Nine electronic databases were searched. Technologies were described and a narrative synthesis of all studies was undertaken. Results: Of 20,925 publications identified, 19 met the inclusion criteria, with 18 technologies assessed. Five categories of communication technologies were identified: video-and tele-conferencing (n = 2); mobile telephony (n = 3); telephone support (n = 3); novel electronic communication devices for transferring clinical information (n = 10); and web-based discussion boards (n = 1). Ten studies showed a positive improvement in HbA1c following the intervention with four studies reporting detrimental increases in HbA1c levels. In fifteen studies communication technologies increased the frequency of contact between patient and healthcare professional. Findings were inconsistent of an association between improvements in HbA1c and increased contact. Limited evidence was available concerning behavioural and care coordination outcomes, although improvement in quality of life, patientcaregiver interaction, self-care and metabolic transmission were reported for some communication technologies. Conclusions: The breadth of study design and types of technologies reported make the magnitude of benefit and their effects on health difficult to determine. While communication technologies may increase the frequency of contact between patient and health care professional, it remains unclear whether this results in improved outcomes and is often the basis of the intervention itself. Further research is needed to explore the effectiveness and cost effectiveness of increasing the use of communication technologies between young people and healthcare professionals

    U.S. Army Small Space Update

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    In December 2010, the U.S. Army flew its first satellite in 50 years, the SMDC-ONE CubeSat. Placed in a very low orbit, the first SMDC-ONE mission lasted only 35 days but enjoyed great success in demonstrating the viability of CubeSats to perform exfiltration of unattended ground sensors data and serve as a communications relay between ground stations over 1000 land miles apart. The success of SMDC-ONE helped shape the U.S. Army’s Space and Missile Defense Command’s (SMDC) programmatic goals for finding new and innovative ways to implement space applications and technologies that aid the warfighter. Since 2010, SMDC has flown ten additional CubeSats including the three SMDC Nanosatellite Program-3 (SNaP) CubeSats currently on orbit (launched October 2015). This paper addresses several SMDC satellite-related development efforts including SNaP, Army Resilient Global On-the-move SATCOM (ARGOS) Ka-band communications microsatellites, Kestrel Eye (an imaging microsatellite), Kestrel Eye Ground Station (KEGS), Common Ground Station (CGS) for all future Army small satellites, supporting technologies including Small Business Innovative Research (SBIR) efforts, the Concepts Analysis Laboratory, SMDC Space Laboratory, the ACES RED effort and earlier responsive launch vehicle activities. Several of the lessons learned from previous as well as ongoing satellite activities are also covered
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