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Carbon dioxide and climate impulse response functions for the computation of greenhouse gas metrics: A multi-model analysis
The responses of carbon dioxide (CO2) and other climate variables to an emission pulse of CO2 into the atmosphere are often used to compute the Global Warming Potential (GWP) and Global Temperature change Potential (GTP), to characterize the response timescales of Earth System models, and to build reduced-form models. In this carbon cycle-climate model intercomparison project, which spans the full model hierarchy, we quantify responses to emission pulses of different magnitudes injected under different conditions. The CO2 response shows the known rapid decline in the first few decades followed by a millennium-scale tail. For a 100 Gt-C emission pulse added to a constant CO2 concentration of 389 ppm, 25 ± 9% is still found in the atmosphere after 1000 yr; the ocean has absorbed 59 ± 12% and the land the remainder (16 ± 14%). The response in global mean surface air temperature is an increase by 0.20 ± 0.12 °C within the first twenty years; thereafter and until year 1000, temperature decreases only slightly, whereas ocean heat content and sea level continue to rise. Our best estimate for the Absolute Global Warming Potential, given by the time-integrated response in CO2 at year 100 multiplied by its radiative efficiency, is 92.5 Ă 10â15 yr W mâ2 per kg-CO2. This value very likely (5 to 95% confidence) lies within the range of (68 to 117) Ă 10â15 yr W mâ2 per kg-CO2. Estimates for time-integrated response in CO2 published in the IPCC First, Second, and Fourth Assessment and our multi-model best estimate all agree within 15% during the first 100 yr. The integrated CO2 response, normalized by the pulse size, is lower for pre-industrial conditions, compared to present day, and lower for smaller pulses than larger pulses. In contrast, the response in temperature, sea level and ocean heat content is less sensitive to these choices. Although, choices in pulse size, background concentration, and model lead to uncertainties, the most important and subjective choice to determine AGWP of CO2 and GWP is the time horizon
From mesoscale to nanoscale mechanics in single-wall carbon nanotubes
The experimental work was carried out in collaboration with W. Wenseleers and S. CambrĂ© at the University of Antwerp, Belgium. The computational results presented have been achieved in part using the Vienna Scientific Cluster (VSC). DJD is grateful for support from the Region RhĂŽne-Alpes through the programme âAccueil-PRO 2014â and from the iMUST Labex programme âMobility in 2015â. ACTD, TFTC, WC, MALM, SB, DM and ASM acknowledge support from the French Agence Nationale de la Recherche through contract ANR-11-NANO-025 âTRI-COâ. ACTD acknowledges postdoctoral grant from Brazilian Ministry of Education (CAPES)
Pressure-induced radial collapse in few-wall carbon nanotubes: A combined theoretical and experimental study
Brazilian authors acknowledge funding from CNPq (grant 307317/2010-2, INCT NanoBioSimes) and Central AnalĂtica-UFC/CT-INFRA-FINEP/PrĂł-Equipamentos-CAPES/CNPq-SisNano-MCTI (grant 402284/2013-5). R. S. Alencar is also in debt to Coordenação de Aperfeiçoamento de Pessoal de NĂvel Superior under the grant No. 99999.004227/2014-00 for financial support. Alexander Soldatov (University of Lulea, Sweden) is warmly acknowledged for discussions on the RBM Raman spectra interpretation at the collapse region
Further studies on a hybrid cell-surface antigen associated with human chromosome 11 using a monoclonal antibody
A monoclonal antibody has been obtained that recognizes an antigen encoded by human chromosome 11. We present evidence that this monoclonal antibody recognizes the same or a similar antigenic activity as that previously called a 1 . Genetic information necessary for a 1 expression and recognition by the monoclonal antibody both map to 11p13 â 11pter. Mutants that have lost a 1 are no longer recognized by the monoclonal antibody. The macroglycolipid fraction of human erythrocyte membranes which contains the a 1 antigenic activity is able to convert antigen-negative Chinese hamster ovary cells into cells which are killed by the monoclonal antibody plus complement.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45556/1/11188_2005_Article_BF01543049.pd
The DUNE far detector vertical drift technology. Technical design report
DUNE is an international experiment dedicated to addressing some of the questions at the forefront of particle physics and astrophysics, including the mystifying preponderance of matter over antimatter in the early universe. The dual-site experiment will employ an intense neutrino beam focused on a near and a far detector as it aims to determine the neutrino mass hierarchy and to make high-precision measurements of the PMNS matrix parameters, including the CP-violating phase. It will also stand ready to observe supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector implements liquid argon time-projection chamber (LArTPC) technology, and combines the many tens-of-kiloton fiducial mass necessary for rare event searches with the sub-centimeter spatial resolution required to image those events with high precision. The addition of a photon detection system enhances physics capabilities for all DUNE physics drivers and opens prospects for further physics explorations. Given its size, the far detector will be implemented as a set of modules, with LArTPC designs that differ from one another as newer technologies arise. In the vertical drift LArTPC design, a horizontal cathode bisects the detector, creating two stacked drift volumes in which ionization charges drift towards anodes at either the top or bottom. The anodes are composed of perforated PCB layers with conductive strips, enabling reconstruction in 3D. Light-trap-style photon detection modules are placed both on the cryostat's side walls and on the central cathode where they are optically powered. This Technical Design Report describes in detail the technical implementations of each subsystem of this LArTPC that, together with the other far detector modules and the near detector, will enable DUNE to achieve its physics goals
Indications for percutaneous endoscopic gastrostomy in complex tuberculosis patients
OBJECTIVES: Percutaneous endoscopic gastrostomy (PEG) is a widely used method for providing long-term administration of tube feeding. Different indications in relation to diseases, impairments and nutritional factors for PEG placement have been mentioned in guidelines. Treatment with PEG has not been described previously for tuberculosis (TB). Our aim was to identify and describe indications and contributing factors for PEG placement in TB patients. METHODS: A retrospective medical record review was conducted of 32 TB patients who required PEG from March 1996 to April 2004. Indications and contributing factors for PEG placement were analysed. RESULTS: PEG placement was based on three different indications. In 18 patients, PEG was used to administer tube feeding, in 4 patients anti-tuberculosis drugs were administered and in 10 patients both tube feeding and antituberculosis drugs were administered. Contributing factors for PEG placement were swallowing disabilities, weakness, anti-tuberculosis drugs and their side effects, pain of neuralgic origin, hiccups and refusal of food and drugs. CONCLUSIONS: In TB, imminent and overt malnutrition, as well as the administration of drugs with a curative aim, are new indications for PEG placement. The use of PEG can overcome various problems in TB treatment and prevent treatment default
Negative-ion chemical ionization gas chromatography-mass spectrometry assay for enantioselective measurement of amphetamines in oral fluid: application to a controlled study with MDMA and driving under the influence cases
Background: Enantioselective analysis of amphetamine (AM), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethaitphetamine (MDMA), and 3,4-methylenedioxyethylamphetamine (MDEA) helps interpret toxicological results. Methods have been described for various matrices, but so far riot for oral fluid, a matrix of increasing importance in testing for drugs of abuse, especially in the context of driving under the influence of drugs (DUID). Methods: After dilution with 200 mu L carbonate buffer (pH 9), oral fluid samples (10-50 mu L) were derivatized with S-heptafluorobutyrylprolyl chloride. The resulting diastereomers. were extracted into 100 mu L of cyclohexane, separated by gas chromatography (HP-5MS column), and detected by mass spectrometry in the negative-ion chemical ionization mode (GC-NICI-MS). The method was validated and applied to samples from a controlled study with MDMA and from authentic DUID cases. Results: The derivatized AM, MA, MDA, MDMA, and MDEA enantiomers were well separated from each other. The method was linear from 5-250 mu g/L per enantiomer of MDA and from 25-1250 mu g/L per enantiomer of AM, MA, MDMA, and MDEA. With the exception of MDEA, analytical recoveries, repeatability, and intermediate precision were within required limits. The analyte concentrations and enantiomer ratios in the application samples correlated only weakly with corresponding published plasma data. Conclusions: This sensitive, reliable, and fast GC-NICI-MS assay enantioselectively measures AM, MA, MDA, and MDMA in oral fluid samples. Prediction of plasma concentrations And enantiomer ratios from respective oral fluid data is riot possible
Drug Testing in Blood: Validated Negative-Ion Chemical Ionization Gas Chromatographic-Mass Spectrometric Assay for Enantioselective Determination of the Designer Drugs MDA, MDMA (Ecstasy) and MDEA and Its Application to Samples From a Controlled Study with MDMA
Background: The enantiomers of the designer drugs 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), and 3,4-methylenedioxyethylamphetamine (MDEA) differ in their pharmacologic and toxicologic potency. The aim of this study was to develop an assay for measuring these enantiomers in small plasma volumes and to analyze samples from a controlled study with MDMA. Methods: The analytes were extracted from 1.0 and increased over time. Concentrations of S-(+)-MDA exceeded those of R-(-).-MDA, their ratios (R vs S) also increasing over time but remaining <1.0. Conclusions: This assay enables sensitive, reliable, and fast enantioselective measurement of MDA, MDMA, and MDEA in small volumes of plasma. The controlled study data confirm previous findings of MDMA and MDA enantiomer ratios (R vs S) increasing over time after ingestion of racemic MDMA
Endoscope disinfection and its pitfalls--requirement for retrograde surveillance cultures.
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70415.pdf (publisher's version ) (Closed access)BACKGROUND AND STUDY AIMS: Several endoscopy-related outbreaks of infection have been reported in recent years. For early recognition of inadequate disinfection of endoscopes we designed a microbiological surveillance system to evaluate the efficacy of the cleaning and disinfection procedure, and to trace disinfection problems to individual endoscopes or washer-disinfectors. METHODS: Our surveillance protocol included anterograde and retrograde sampling, a decision algorithm, genetic fingerprinting, and scanning electron microscopy. RESULTS: Over a period of 29 months we found an increasing number of patient-ready endoscopes testing positive for Candida species other than albicans, especially C. parapsilosis. These yeasts were also isolated from the washer-disinfectors. The number of positive tests for Candida species varied from 1 out of 21 to 14 out of 27 samples from nine frequently used endoscopes. The number of colony-forming units per milliliter ranged from 1 - 10 to 3000 for endoscopes and 0.002 to 0.06 for the washer disinfectors. DNA fingerprinting was not able to discriminate different strains within C. parapsilosis. CONCLUSIONS: Our protocol was able to detect a structural problem in the endoscope disinfection process. Retrograde sampling was crucial for this purpose, because it has much higher sensitivity than anterograde sampling. Endoscopes with damaged working channels are probably the source of the contamination problem with Candida species
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