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Additional Measurements (additional + measurement)
Selected AbstractsFöhn as a response to changing upstream and downstream air massesTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 635 2008Georg J. Mayr Abstract Observations of föhn from the field phase of the Mesoscale Alpine Programme (MAP) are used to study how differences between the air masses upstream and downstream of the central Alpine crest determine whether the flow can descend to the lee as either shallow föhn, when it passes through passes in the mountains, or deep föhn, when it overflows the Alpine crest. First, the föhn case of 30 October 1999 is examined using ECMWF analyses and radiosonde data at various upstream and downstream locations. Additional measurements from aircraft, dropsondes, an instrumented car and automatic weather stations are then used for a detailed study of the föhn flow across the Brenner Pass. Advection of cold air around the eastern edges of the Alps and warm air around the western edge of the Alps ahead of a synoptic ridge set up a reservoir of colder air on the south side of the Alps and a reservoir of warmer air to the north. The depth to where the air was colder on the southern side was sufficient for a shallow föhn to flow through the pass. After the passage of the ridge axis, synoptic cold air advection provided another source of colder air, this time from the southwest, growing deeper with time and having a synoptically imposed cross-barrier flow component. The maximum depth to where the air upstream was colder than downstream extended just above the peaks of the highest mountains. An analysis of the detailed measurements across the Brenner Pass showed that this depth was also the top of the layer that descended and accelerated down the lee slopes of the Wipp Valley. Upstream, air above the föhn layer had an even stronger cross-barrier component yet did not descend because it did not have lower potential temperatures than the downstream side at that level. Deep föhn never developed. An examination of other well-documented MAP föhn cases confirmed the conclusion from the 30 October event that shallow and deep föhns , at least for the central Alps , are mostly a response to differences in air masses between the upstream and downstream side. A cross-barrier component of the flow was only a modification but in itself not sufficient to cause the flow to both descend and accelerate down the lee slope, unless potential temperatures on the upstream side were lower in this layer than on the downstream side. Copyright © 2008 Royal Meteorological Society [source] Vinyl-Pyridinium Triphenylamines: Novel Far-Red Emitters with High Photostability and Two-Photon Absorption Properties for Staining DNACHEMBIOCHEM, Issue 4 2007Clémence Allain Dr. Abstract A series of mono-, bis- and trisvinyl-pyridinium triphenylamines (TP-py) has been synthesised and evaluated for its one- and two-photon absorption (2PA) induced-fluorescence properties under biological conditions. Interestingly, these compounds are only weakly fluorescent in water, whereas their fluorescence emissions are strongly restored (exaltation factors of 20,100) upon binding to double-stranded DNA. Additional measurements in glycerol indicate that the fluorescence increases are the result of immobilisation of the dyes in the DNA matrix, which inhibits rotational de-excitation modes. This particular feature is especially remarkable in the case of the bis and tris derivatives (TP-2,py, TP-3,py), which each display a high affinity (Kd ,,M) for dsDNA. TPIF measurements have shown that TP-2,py and TP-3,py each have a large 2PA cross section (, up to 700 GM) both in glycerol and in the presence of DNA, which ranks them amongst the best 2PA biological fluorophores. Finally, one- and two-photon confocal imaging in cells revealed that these compounds perform red staining (,em=660,680 nm) of nuclear DNA with excellent contrast. The remarkable optical properties of the TP-py series, combined with their high photostability and their easy synthetic access, make these compounds extremely attractive for use in confocal and 2PA microscopy. [source] Airway obstruction at time of symptoms prompting use of reliever therapy in children with asthmaACTA PAEDIATRICA, Issue 6 2010AFJ Brouwer Abstract Background:, In asthma treatment, doses of inhaled corticosteroids are often adapted to symptoms and need for bronchodilators. However, in cross-sectional studies in emergency room settings, lung function and respiratory symptoms are not always concordant. Available longitudinal data are based on written peak flow diaries, which are unreliable. Using home spirometry, we studied prospectively whether mild respiratory symptoms, prompting reliever therapy are accompanied by a clinically relevant drop in lung function in children with asthma. Methods:, For 8 weeks, children with asthma scored symptoms and measured peak expiratory flow (PEF) and forced expiratory volume in 1 sec (FEV1) on a home spirometer twice daily. Additional measurements were recorded when respiratory symptoms prompted them to use bronchodilators. Results:, The mean difference between symptom free days and at times of symptoms was 6.6% of personal best for PEF (95% CI: 3.2,10.0; p = 0.0004) and 6.0% of predicted for FEV1 (95% CI: 3.0,9.0; p = 0.0004). There was complete overlap in PEF and FEV1 distributions between symptom free days and at times of symptoms. Conclusions:, Although statistically significant, the degree of airway narrowing at times of respiratory symptoms, prompting the use of reliever therapy, is highly variable between patients, limiting the usefulness of home spirometry to monitor childhood asthma. [source] Discovery of 17 new sharp-lined Ap stars with magnetically resolved lines,MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2008L. M. Freyhammer ABSTRACT Chemically peculiar A stars (Ap) are extreme examples of the interaction of atomic element diffusion processes with magnetic fields in stellar atmospheres. The rapidly oscillating Ap stars provide a means for studying these processes in three dimensions and are at the same time important for studying the pulsation excitation mechanism in A stars. As part of the first comprehensive, uniform, high-resolution spectroscopic survey of Ap stars, which we are conducting in the Southern hemisphere with the Michigan Spectral Catalogues as the basis of target selection, we report here the discovery of 17 new magnetic Ap stars having spectroscopically resolved Zeeman components from which we derive magnetic field moduli in the range 3,30 kG. Among these are (1) the current second strongest known magnetic A star, (2) a double-lined Ap binary with a magnetic component and (3) an A star with particularly peculiar and variable abundances. Polarimetry of these stars is needed to constrain their field geometries and to determine their rotation periods. We have also obtained an additional measurement of the magnetic field of the Ap star HD 92499. [source] Carbon dioxide assimilation by a wetland sedge canopy exposed to ambient and elevated CO2: measurements and model analysisFUNCTIONAL ECOLOGY, Issue 2 2003D. P. Rasse Summary 1The wetland sedge Scirpus olneyi Gray displays fast rates of CO2 assimilation and responds positively to increased atmospheric CO2 concentration. The present study was aimed at identifying the ecophysiological traits specific to S. olneyi that drive these CO2 -assimilation patterns under ambient and elevated CO2 conditions. 2The net ecosystem exchange (NEE) of CO2 between S. olneyi communities and the atmosphere was measured in open-top chambers. 3We developed a new mechanistic model for S. olneyi communities based on published ecophysiological data and additional measurements of photosynthetic parameters. 4Our NEE measurements confirmed that S. olneyi communities have a high rate of summertime CO2 assimilation, with noontime peaks reaching 40 µmol CO2 m,2 ground s,1 on productive summer days, and that elevated CO2 increased S. olneyi CO2 assimilation by c. 35,40%. 5Using S. olneyi -specific ecophysiological parameters, comparison with measured NEE showed that the model accurately simulated these high rates of CO2 uptake under ambient or elevated CO2. 6The model pointed to the Rubisco capacity of Scirpus leaves associated with their high total nitrogen content as the primary explanation for the high rates of CO2 assimilation, and indicated that the vertical-leaf canopy structure of S. olneyi had comparatively little influence on CO2 assimilation. [source] Simultaneous estimation of diffusive Volatile Organic Compound (VOC) fluxes and Non-Aqueous Phase Liquid (NAPL) saturation in the vadose zoneGROUND WATER MONITORING & REMEDIATION, Issue 2 2005David Werner Soil-gas monitoring is a widely used tool to observe the migration of volatile organic compounds (VOCs) at contaminated sites. By combining this technique with natural gradient tracer methods, diffusive contaminant fluxes can be measured in situ, and non,aqueous phase liquid (NAPL) can be detected and roughly quantified. This work describes the new approach and its application at a field site in Denmark with an emplaced NAPL contamination. Soil-gas probes with a low dead volume were installed at 1-m depths in the sandy vadose zone, and a small volume of gas containing conservative and partitioning tracers was injected. Soil-gas samples were withdrawn subsequently during 1 to 4 h and analyzed simultaneously for VOCs and tracers. Tracers detected the NAPL reliably, and the combined data allowed for a close delineation of the source zone. The calculated NAPL saturation deviated by up to a factor of 3 from the analyses of soil cores. Better agreement was found by taking the NAPL composition into consideration, which is, however, generally unknown at the actual field sites. In addition, the tracers were also used to estimate effective diffusion coefficients in situ, which varied by a factor of 2 between various locations. From these data, diffusive contaminant vapor fluxes were quantified without additional laboratory experiments or the use of empirical relationships. The new approach yields a better site investigation with a few additional measurements. [source] The reaction of OH with acetaldehyde and deuterated acetaldehyde: Further insight into the reaction mechanism at both low and elevated temperaturesINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 8 2006Philip H. Taylor The pulsed laser photolysis/laser-induced fluorescence technique has been used to conduct additional measurements of the gas-phase CH3CHO + OH reaction. These measurements were conducted to verify the complex temperature dependence previously observed by the authors and to acquire mechanistic information about the reaction mechanism in the form of primary kinetic isotope effects. Primary kinetic isotope effect measurements at temperatures of 297, 383, 600, and 860 K indicate that H abstraction from the acetyl group dominates that of the methyl group at low to modest temperatures (,600 K) and H abstraction from the methyl group dominates that from the acetyl group at higher temperatures (860 K). A bi-exponential © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 38: 489,495, 2006 [source] Oasis: Onboard autonomous science investigation system for opportunistic rover scienceJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 5 2007Rebecca Castano The Onboard Autonomous Science Investigation System has been developed to enable a rover to identify and react to serendipitous science opportunities. Using the FIDO rover in the Mars Yard at JPL, we have successfully demonstrated a fully autonomous opportunistic science system. The closed loop system tests included the rover acquiring image data, finding rocks in the image, analyzing rock properties and identifying rocks that merit further investigation. When the system on the rover alerts the rover to take additional measurements of interesting rocks, the planning and scheduling component determines if there are enough resources to meet this additional science data request. The rover is then instructed to either turn toward the rock, or to actually move closer to the rock to take an additional, close-up image. Prototype dust devil and cloud detection algorithms were delivered to an infusion task which refined the algorithms specifically for Mars Exploration Rovers (MER). These algorithms have been integrated into the MER flight software and were recently uploaded to the rovers on Mars. © 2007 Wiley Periodicals, Inc. [source] Characteristics and Referral of Emergency Department Patients with Elevated Blood PressureACADEMIC EMERGENCY MEDICINE, Issue 9 2007Brigitte M. Baumann MD, MSCE Objectives: To assess the prevalence, characteristics, and referral to health care of emergency department (ED) patients with elevated blood pressure (BP) and to compare those without a history of hypertension (HTN) with suboptimally controlled, known-hypertensive patients. Methods: A prospective, observational study was conducted in non,critically ill adults with a triage systolic blood pressure (sBP) of ,140 or with a diastolic blood pressure (dBP) of ,90 mmHg. Two additional measurements were obtained, and a standardized questionnaire recorded demographics, medical history, and ED staff referrals. Results: Of 1,719 nonpregnant adults, 991 agreed to participate, of whom 455 had elevated triage BP values. Using the mean of three measurements, 305 (67%) had an sBP of ,140 or a dBP of ,90 mm Hg (mean sBP = 157 and mean dBP = 89 mm Hg). Subjects with no prior history of HTN (n = 105) were predominantly male, younger, and more likely to smoke and consume alcohol than were known-hypertensive patients (n = 200). Three quarters of all subjects had access to primary health care; however, time elapsed since the last BP assessment was greater (155 vs. 53 d, p = 0.03) in subjects with no previous history. These subjects were also less likely to be informed of their elevated BP (33% vs. 50%, p = 0.02) or to be instructed by ED staff to obtain a repeat measurement (13% vs. 31%, p = 0.001). Conclusions: Of ED patients with elevated BP, one third had no prior history, and the remainder were suboptimally controlled hypertensive patients. Both groups were inadequately informed of their elevated BPs, and the group with no prior history of HTN, the population likely to obtain the greatest health benefit, had the lowest referral rate. [source] | ||||||||||||||||