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In-situ comparison of the NOy instruments flown in MOZAIC and SPURT
No full textTwo aircraft instruments for the measurement of total odd nitrogen (NOy) were compared side by side aboard a Learjet A35 in April 2003 during a campaign of the AFO2000 project SPURT (Spurengastransport in der Tropopausenregion). The instruments albeit employing the same measurement principle (gold converter and chemiluminescence) had different inlet configurations. The ECO-Physics instrument operated by ETH-Zürich in SPURT had the gold converter mounted outside the aircraft, whereas the instrument operated by FZ-Jülich in the European project MOZAIC III (Measurements of ozone, water vapour, carbon monoxide and nitrogen oxides aboard Airbus A340 in-service aircraft) employed a Rosemount probe with 80 cm of FEP-tubing connecting the inlet to the gold converter. The NOy concentrations during the flight ranged between 0.3 and 3 ppb. The two data sets were compared in a blind fashion and each team followed its normal operating procedures. On average, the measurements agreed within 7%, i.e. within the combined uncertainty of the two instruments. This puts an upper limit on potential losses of HNO3 in the Rosemount inlet of the MOZAIC instrument. Larger transient deviations were observed during periods after calibrations and when the aircraft entered the stratosphere. The time lag of the MOZAIC instrument observed in these instances is in accordance with the time constant of the MOZAIC inlet line determined in the laboratory for HNO3
Dov Noy (interview)
No full textThis interview is included in the Indiana University Folklore Institute, 1987 Collection at the Indiana University Center for the Study of History and Memory. In this interview, Dov Noy discusses his involvement with the Indiana University Folklore Institute. Originally from Poland, Noy was educated in Israel, when he was stranded there when World War II started. During his time with the British Army, Noy became interested in folk narrative. He originally came to IU to study comparative literature, but quickly switched to folklore. Noy speaks of the Summer Institute and the classes he taught. He also describes his perceptions and relationship with Stith Thompson, whom he felt was very welcoming to students, even though he may not have been a good lecturer. Noy discusses his relationship with Richard Dorson. Noy discusses the development of folklore studies in Israel, which he has been active in promoting since his return in the late 1950s. This collection is part of the Indiana University Folklore Institute, 1987 collection which is available at the Indiana University Center for the Study of History and Memory. It consists of: 27 pages; 1 cassette (1 7/8 ips, 53 minutes) with no index, and a newspaper article. This collection is closed until 2015 except to authorized project personnel. The IU Folklore Institute, 1987 collection deals with the beginning, the building, and the growth of the Indiana University (IU) Folklore Institute into an internationally recognized program. The interviewees are mostly students and/or faculty of the folklore program from the 1940s to the 1980s. They discuss those who most influenced and impacted the institute, namely Stith Thompson and Richard M. Dorson. They share their memories and experiences of the time they spent, or continue to spend, in the IU Folklore Institute
The CKC Challenge: Exploring Tools for Collaborative Knowledge Construction
No full textThe great success of Web 2.0 is mainly fuelled by an infrastructure that allows web users to create, share, tag, and connect content and knowledge easily. The tools for developing structured knowledge in this manner have started to appear as well. However, there are few, if any, user studies that are aimed at understanding what users expect from such tools, what works and what doesn't. We organized the Collaborative Knowledge Construction (CKC) Challenge to assess the state of the art for the tools that support collaborative processes for creation of various forms of structured knowledge. The goal of the Challenge was to get users to try out different tools and to learn what users expect from such tools /features that users need, features that they like or dislike. The Challenge task was to construct structured knowledge for a portal that would provide information about research. The Challenge design contained several incentives for users to participate. Forty-nine users registered for the Challenge; thirty three of them participated actively by using the tools. We collected extensive feedback from the users where they discussed their thoughts on all the tools that they tried. In this paper, we present the results of the Challenge, discuss the features that users expect from tools for collaborative knowledge constructions, the features on which Challenge participants disagreed, and the lessons that we learned
Summertime NOy speciation at the Jungfraujoch, 3580 m above sea level, Switzerland
No full textDuring summer 1997, speciated reactive nitrogen (NO, NO2, peroxyacetyl nitrate (PAN), HNO3, and particulate nitrate) was measured in conjunction with total reactive nitrogen (NOy) at the high-alpine research station Jungfraujoch (JFJ), 3580 m above sea level (asl). The individually measured NOy components averaged to 82% of total NOy. PAN was the most abundant reactive nitrogen compound and composed on average 36% of NOy, followed by NOx, (22%), particulate nitrate (17%), and HNO3 (7%). The NOx/NOy ratio averaged 0.25, but significantly lower values (0.15–0.20) were observed in the presence of high NOy mixing ratios. A classification of the data by synoptic weather conditions indicated that thermally driven vertical transport has a strong impact on the mixing ratios measured at the JFJ during summer. A strong diurnal cycle with maximum mixing ratios in the late afternoon was observed for convective days with north-westerly advection at 500 hPa. In contrast, during a period of convective days with a wind speed below 7.5 m/s at 500 hPa, no obvious diurnal cycle was observed. Under these meteorological conditions the convective boundary layer can be significantly higher over the Alps (i.e., around 4 km asl) than over the surrounding lowlands. Subsequent advection may finally result in the export of reactive nitrogen reservoir compounds to the free troposphere and hence influence global atmospheric chemistry
agnesnoy/SerraNA: SerraNA v1.0
No full textBy Victor Velasco-Berrelleza and Agnes Noy Published at: V Velasco-Berrelleza, M Burmann, JW Shepherd, MC Leake, R Golestanian, A Noy (2020). "SerraNA: a program to determine nucleic acids elasticity from simulation data" Phys Chem Chem Phys, 22, 19254-19266 https://doi.org/10.1039/D0CP02713
FDI and Trade -- Two Way Linkages?
No full textThe purpose of this paper is to investigate the intertemporal linkages between FDI and disaggregated measures of international trade. We outline a model exemplifying some of these linkages, describe several methods for investigating two-way feedbacks between various categories of trade, and apply them to the recent experience of developing countries. After controlling for other macroeconomic and institutional effects, we find that the strongest feedback between the sub-accounts is between FDI and manufacturing trade. More precisely, applying Geweke (1982)%u2019s decomposition method, we find that most of the linear feedback between trade and FDI (81%) can be accounted for by Granger-causality from FDI gross flows to trade openness (50%) and from trade to FDI (31%). The rest of the total linear feedback is attributable to simultaneous correlation between the two annual series.
Observation of mesospheric air inside the arctic stratospheric polar vortex in early 2003
No full textDuring several balloon flights inside the Arctic polar vortex in early 2003, unusual trace gas distributions were observed, which indicate a strong influence of mesospheric air in the stratosphere. The tuneable diode laser (TDL) instrument SPIRALE (Spectroscopie InFrarouge par Absorption de Lasers Embarqués) measured unusually high CO values (up to 600 ppb) on 27 January at about 30 km altitude. The cryosampler BONBON sampled air masses with very high molecular Hydrogen, extremely low SF6 and enhanced CO values on 6 March at about 25 km altitude. Finally, the MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) Fourier Transform Infra-Red (FTIR) spectrometer showed NOy values which are significantly higher than NOy* (the NOy derived from a correlation between N2O and NOy under undisturbed conditions), on 21 and 22 March in a layer centred at 22 km altitude. Thus, the mesospheric air seems to have been present in a layer descending from about 30 km in late January to 25 km altitude in early March and about 22 km altitude on 20 March. We present corroborating evidence from a model study using the KASIMA (KArlsruhe Simulation model of the Middle Atmosphere) model that also shows a layer of mesospheric air, which descended into the stratosphere in November and early December 2002, before the minor warming which occurred in late December 2002 lead to a descent of upper stratospheric air, cutting of a layer in which mesospheric air is present. This layer then descended inside the vortex over the course of the winter. The same feature is found in trajectory calculations, based on a large number of trajectories started in the vicinity of the observations on 6 March. Based on the difference between the mean age derived from SF6 (which has an irreversible mesospheric loss) and from CO2 (whose mesospheric loss is much smaller and reversible) we estimate that the fraction of mesospheric air in the layer observed on 6 March, must have been somewhere between 35% and 100%
Variations of DNA polymerase-alfa and -beta during prolonged stimulation of human lymphocytes.
No full textStimulation of human lymphocytes with phytohemagglutinin is known to induce an increase in overall DNA polymerase activity (DNA nucleotidyltransferase; deoxynucleosidetriphosphate:DNA deoxynucleotidyltransferase, EC 2.7.7.7). Previous work [Pedrali Noy, G., Dalprà, L. Pedrini, A. M., Ciarrocchi, G., Giulotto, E., Nuzzo, F. & Falaschi, A. (1974) Nucleic Acids Res. 1, 1183] has shown that two subsequent waves of induction of DNA polymerase can be observed in this system; a first wave occurs in parallel with the increase in DNA replication rate; a second one occurs when the DNA synthesis rate is returned to minimal levels; the second peak is parallel to a maximum in DNA ligase and DNase levels. In the present work we have measured the levels of the DNA polymerases-alpha and -beta in phytohemagglutinin-stimulated lymphocytes during a 12-day period; both enzymes are present at detectable levels at time zero; in correspondence to the peak of DNA synthesis rate (between the fourth and fifth day) a peak of DNA polymerase-alpha is observed, increasing by a factor of approximately 20-fold over the zero time value; subsequently, the level of DNA polymerase-alpha decreases in parallel with DNA synthesis rate. The DNA polymerase-beta is also increased in correspondence to the peak in DNA synthesis rate, but reaches its maximum at later times, between the eighth and tenth day of incubation. The capacity of stimulated lymphocytes to perform repair synthesis following UV damage was measured in the same cells used for the enzyme activity determinations; this capacity also shows two maxima: a first one correlated with the peak in DNA replication rate, and a second one correlated with the peak of DNA polymerase-beta. These data suggest a certain tendency to the specialization of functions in human cell DNA polymerases; the alpha-enzyme seems mainly correlated with DNA replication, whereas the beta-enzyme seems more correlated with the ability of the cell to perform repair type synthesis
Variations of DNA polymerase-alpha and -beta during prolonged stimulation of human lymphocytes
No full textStimulation of human lymphocytes with phytohemagglutinin is known to induce an increase in overall DNA polymerase activity (DNA nucleotidyltransferase; deoxynucleosidetriphosphate:DNA deoxynucleotidyltransferase, EC 2.7.7.7). Previous work [Pedrali Noy, G., Dalpra, L. Pedrini, A. M., Ciarrocchi, G., Giulotto, E., Nuzzo, F. & Falaschi, A. (1974) Nucleic Acids Res. 1, 1183] has shown that two subsequent waves of induction of DNA polymerase can be observed in this system; a first wave occurs in parallel with the increase in DNA replication rate; a second one occurs when the DNA synthesis rate is returned to minimal levels; the second peak is parallel to a maximum in DNA ligase and DNase levels. In the present work we have measured the levels of the DNA polymerases-alpha and -beta in phytohemagglutinin-stimulated lymphocytes during a 12-day period; both enzymes are present at detectable levels at time zero; in correspondence to the peak of DNA synthesis rate (between the fourth and fifth day) a peak of DNA polymerase-alpha is observed, increasing by a factor of approximately 20-fold over the zero time value; subsequently, the level of DNA polymerase-alpha decreases in parallel with DNA synthesis rate. The DNA polymerase-beta is also increased in correspondence to the peak in DNA synthesis rate, but reaches its maximum at later times, between the eighth and tenth day of incubation. The capacity of stimulated lymphocytes to perform repair synthesis following UV damage was measured in the same cells used for the enzyme activity determinations; this capacity also shows two maxima: a first one correlated with the peak in DNA replication rate, and a second one correlated with the peak of DNA polymerase-beta. These data suggest a certain tendency to the specialization of functions in human cell DNA polymerases; the alpha-enzyme seems mainly correlated with DNA replication, whereas the beta-enzyme seems more correlated with the ability of the cell to perform repair type synthesis
Seasonality of reactive nitrogen oxides (NOy) at Neumayer Station, Antarctica
No full textNO, NOy (total reactive nitrogen oxides), gaseous HNO3, and particulate nitrate (p-NO3−) were measured at Neumayer Station from February 1999 to January 2000. In addition, during February 1999, the NOy component species peroxyacetyl nitrate (PAN) and methyl, ethyl, i-propyl, and n-propyl nitrates were determined. We found a mean NOy mixing ratio of 46 ± 29 pptv, with significantly higher values between February and end of May (58 ± 35 pptv). Between February and November, the (HNO3 + p-NO3−)/NOy ratio was extremely low (around 0.22) and in contrast to NOy the seasonality of p-NO3− and HNO3 showed a distinct maximum in November and December, leading to a (HNO3 + p-NO3−)/NOy ratio of 0.66. Trajectory analyses and radioisotope measurements (7Be, 10Be, 210Pb, and 222Rn) indicated that the upper troposphere or stratosphere was the main source region of the observed NOy with a negligible contribution of ground-level sources at northward continents. Frequent maxima of NOy mixing ratios up to 100 pptv are generally associated with air mass transport from the free troposphere of continental Antarctica, while air masses with the lowest NOy mixing ratios were typically advected from the marine boundary layer
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