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Search Results: 1 - 10 of 249185 matches for " Enrico Br?nnimann "
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Annular pancreas associated with duodenal carcinoma
Enrico Brnnimann, Silke Potthast, Tatjana Vlajnic, Daniel Oertli, Oleg Heizmann
World Journal of Gastroenterology , 2010,
Abstract: Annular pancreas (AP) is a rare congenital anomaly. Coexisting malignancy has been reported only in a few cases. We report what is, to the best of our knowledge, the first case in the English literature of duodenal adenocarcinoma in a patient with AP. In a 55-year old woman with duodenal outlet stenosis magnetic resonance cholangiopancreatography showed an aberrant pancreatic duct encircling the duodenum. Duodenojejunostomy was performed. Eight weeks later she presented with painless jaundice. Duodenopancreatectomy revealed a duodenal adenocarcinoma, surrounded by an incomplete AP. Thus, co-existent malignancy with AP can be present without obstructive jaundice and without being visible through preoperative diagnostics.
Re-evaluation of the 1950–1962 total ozone record from Longyearbyen, Svalbard
C. Vogler, S. Br nnimann,G. Hansen
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2006,
Abstract: The historical total ozone measurements taken with Dobson Spectrophotometer #8 at Longyearbyen (78.2° N, 15.6° E), Svalbard, Norway, in the period 1950–1962 have been re-analyzed and homogenized based on the original measurement logs, using present-day procedures. In lack of sufficient calibration information, an empirical quality assessment was performed, based on a climatological comparison with ozone measurements in Troms , using TOMS data at both sites in the period 1979–2001, and ground-based Dobson data in the period 1950–1962. The assessment revealed that the C wavelength pair direct-sun (DS) measurements are most trustworthy (and most frequent), while the WMO standard reference mode AD direct-sun has a systematic bias. Zenith-blue (ZB) measurements at solar zenith angles (SZA) <78° were adjusted to DS data using different empirical functions before and after 1957 (the start of the International Geophysical Year). ZB measurements at larger SZAs were homogenized by means of a normalization function derived from days with measurements over a wide range of SZAs. Zenith-cloudy measurements, which are particularly frequent during the summer months, were homogenized by applying correction factors depending on the cloud type (high thin clouds and medium to low thick clouds). The combination of all measurements yields a total of 4685 single values, covering 1637 days from September 1950 to September 1962; moon measurements during the polar night add another 137 daily means. The re-evaluated data show a convincing consistence with measurements since 1979 (TOMS, SAOZ, Dobson) as well as with the 1957–1962 data stored at the World Ozone and UV Data Centre (WOUDC).
Re-evaluation of the 1950–1962 total ozone record from Longyearbyen, Svalbard
C. Vogler,S. Brnnimann,G. Hansen
Atmospheric Chemistry and Physics Discussions , 2006,
Abstract: The historical total ozone measurements taken with Dobson Spectrophotometer #8 at Longyearbyen, Svalbard, Norway, in the period 1950–1962 have been re-analyzed and homogenized based on the original measurement logs, using updated relevant parameters. In lack of sufficient calibration information, an empirical quality assessment was performed, based on a climatological comparison with ozone measurements in Troms , using TOMS data at both sites in the period 1979–2001, and Dobson data in the period 1950–1962. The assessment revealed that, as in the case of the Troms measurements, the C wavelength pair direct-sun measurements are most trustworthy (and most frequent), while the WMO standard reference mode AD direct-sun has a systematic bias relative to this data set. Zenith-blue (ZB) measurements at solar zenith angles (SZA) <80° were homogenized using two different polynomials before and from 1957; also ZB measurements at larger SZAs were homogenized by means of a normalization function derived from days with measurements over a wide range of SZAs. CC' zenith-cloudy measurements, which are particularly frequent during the summer months, were homogenized by applying correction factors for only two different cloud types: high thin clouds and medium/low/thick clouds; a further diversification of corrections reflecting cloud conditions did not prove significant. The combination of all measurements yields a total of 4837 single values, covering 1676 days from September 1950 to September 1962; moon measurements during the polar night add another 137 daily means. The re-evaluated data show a convincing agreement with measurements since 1979 (TOMS, SAOZ, Dobson) as well as with the 1957–1962 data stored at the World Ozone and UV Data Centre (WOUDC).
Two case studies on the interaction of large-scale transport, mesoscale photochemistry, and boundary-layer processes on the lower tropospheric ozone dynamics in early spring
S. Brnnimann,F. C. Siegrist,W. Eugster,R. Cattin
Annales Geophysicae (ANGEO) , 2003,
Abstract: The vertical distribution of ozone in the lower troposphere over the Swiss Plateau is investigated in detail for two episodes in early spring (February 1998 and March 1999). Profile measurements of boundary-layer ozone performed during two field campaigns with a tethered balloon sounding system and a kite are investigated using regular aerological and ozone soundings from a nearby site, measurements from monitoring stations at various altitudes, backward trajectories, and synoptic analyses of meteorological fields. Additionally, the effect of in situ photochemistry was estimated for one of the episodes employing the Metphomod Eulerian photochemical model. Although the meteorological situations were completely different, both cases had elevated layers with high ozone concentrations, which is not untypical for late winter and early spring. In the February episode, the highest ozone concentrations of 55 to 60 ppb, which were found at around 1100 m asl, were partly advected from Southern France, but a considerable contribution of in situ photochemistry is also predicted by the model. Below that elevation, the local chemical sinks and surface deposition probably overcompensated chemical production, and the vertical ozone distribution was governed by boundary-layer dynamics. In the March episode, the results suggest that ozone-rich air parcels, probably of stratospheric or upper tropospheric origin, were advected aloft the boundary layer on the Swiss Plateau. Key words. Atmospheric composition and structure (pollution – urban and regional; troposphere – composition and chemistry) – Meteorology and atmospheric dynamics (mesoscale meteorology)
The 1986–1989 ENSO cycle in a chemical climate model
S. Brnnimann,M. Schraner,B. Müller,A. Fischer
Atmospheric Chemistry and Physics Discussions , 2006,
Abstract: A pronounced ENSO cycle occurred from 1986 to 1989, accompanied by distinct dynamical and chemical anomalies in the global troposphere and stratosphere. Reproducing these effects with current climate models not only provides a model test but also contributes to our still limited understanding of ENSO's effect on stratosphere-troposphere coupling. We performed several sets of ensemble simulations with a chemical climate model (SOCOL) forced with global sea surface temperatures. Results were compared with observations and with large-ensemble simulations performed with an atmospheric general circulation model (MRF9). We focus our analysis on the extratropical stratosphere and its coupling with the troposphere. In this context, the circulation over the North Atlantic sector is particularly important. Observed differences between the El Ni o winter 1987 and the La Ni a winter 1989 include a negative North Atlantic Oscillation index with corresponding changes in temperature and precipitation patterns, a weak polar vortex, a warm Arctic middle stratosphere, negative and positive total ozone anomalies in the tropics and at middle to high latitudes, respectively, as well as anomalous upward and poleward Eliassen-Palm (EP) flux in the midlatitude lower stratosphere. Most of the tropospheric features are well reproduced in the ensemble means in both models, though the amplitudes are underestimated. In the stratosphere, the SOCOL simulations compare well with observations with respect to zonal wind, temperature, EP flux, and ozone, but magnitudes are underestimated in the middle stratosphere. The polar vortex strength is well reproduced, but within-ensemble variability is too large for obtaining a significant signal in Arctic temperature and ozone. With respect to the mechanisms relating ENSO to stratospheric circulation, the results suggest that both, upward and poleward components of anomalous EP flux are important for obtaining the stratospheric signal and that an increase in strength of the Brewer-Dobson circulation is part of that signal.
Influence of the sunspot cycle on the Northern Hemisphere wintertime circulation from long upper-air data sets
Y. Brugnara,S. Brnnimann,J. Luterbacher,E. Rozanov
Atmospheric Chemistry and Physics Discussions , 2012, DOI: 10.5194/acpd-12-30371-2012
Abstract: Here we present a study of the 11-yr sunspot cycle's imprint in the Northern Hemisphere atmospheric circulation, using three recently developed gridded upper-air data sets which extend back to the early twentieth century. We find a robust response of the tropospheric late-wintertime circulation to the sunspot cycle, independent from the data set. This response is particularly significant over Europe, but results show that it is not directly related to a North Atlantic Oscillation modulation; instead, it reveals a significant connection to the more meridional Eurasian pattern. The magnitude of mean seasonal temperature changes over the European land areas locally exceeds 1 K in the lower troposphere over a sunspot cycle. We also analyse surface data to address the question whether the solar signal over Europe is temporally stable for a longer 250 yr period. The results increase our confidence on the existence of an influence of the 11-yr cycle on the European climate, although the signal is much weaker in the first half of the period compared to the second half. The last solar minimum (2005 to 2010), which was not included in our analysis, shows anomalies that are consistent with our statistical results for earlier solar minima.
A global historical ozone data set and signatures of El Ni o and the 11-yr solar cycle
S. Brnnimann,J. Bhend,J. Franke,S. Flückiger
Atmospheric Chemistry and Physics Discussions , 2013, DOI: 10.5194/acpd-13-7767-2013
Abstract: We present a vertically resolved (with pressure as the vertical coordinate) zonal mean monthly mean global ozone data set spanning the period 1900 to 2008, called HISTOZ.1.0. It is based on a new approach that combines information from an ensemble of chemistry climate model (CCM) simulations with historical total ozone information. The CCM simulations incorporate important external drivers of stratospheric chemistry and dynamics (in particular solar and volcanic effects, greenhouse gases and ozone depleting substances, sea-surface temperatures, and the Quasi-Biennial Oscillation). The historical total ozone observations include ground-based measurements from the 1920s onward and satellite observations from 1970 to 1976. An off-line data assimilation approach (Ensemble Square Root Filter) is used to combine model simulations, observations, and information on the observation error. The period starting in 1979 was used for validation with existing ozone data sets and therefore only ground-based measurements were assimilated. Results demonstrate considerable skill from the CCM simulations alone. While the observations provide little additional skill at the full spatio-temporal resolution, they do increase the skill at lower spatio-temporal resolutions and specifically for total ozone. Analyses of HISTOZ.1.0 with respect to the effects of El Ni o/Southern Oscillation (ENSO) and of the 11 yr solar cycle on stratospheric ozone from 1934 to 1979 qualitatively confirm previous studies that focussed on the post-1979 period. However, a more pronounced effect of ENSO and slightly weaker effect of the 11 yr solar cycle are found in the earlier period. Several possible future improvements of HISTOZ.1.0 are discussed.
DO TESTIMONIES OF TRAUMATIC EVENTS DIFFER DEPENDING ON THE INTERVIEWER?
Rebecca Brnnimann,Jane Herlihy,Julia Müller,Ulrike Ehlert
European Journal of Psychology Applied to Legal Context , 2013,
Abstract: While differences in witness narratives due to different interviewers may have implications for their credibility in court, this study considers how investigative interviews by different parties to the proceedings, as well as the gender and nationality of interviewers, can influence the testimony of witnesses in court who share comparable traumatic experiences. The foundation of the analysis was answers given to judges, prosecutors, civil party lawyers and defence lawyers in the Extraordinary Chambers in the Courts of Cambodia (ECCC) located in Phnom Penh. Transcribed testimonies of 24 victim witnesses and civil parties which were translated from Khmer into English were analysed using a computer-based text analysis program, the Linguistic Inquiry and Word Count (LIWC). Results showed that when answering questions by females, witnesses used significantly more cognitive process words. When interviewed by international rather than by Cambodian parties to the proceeding witness accounts were composed of significantly more verbal expressions of affective processes and of perceptual processes. Furthermore, witnesses used most cognitive and affective process words during the interview by civil party lawyers and defence lawyers. These results may be due to a prior supportive relationship between civil parties and their lawyers and due to a more interrogative question style by the defence lawyers, who attempt to undermine the credibility of the interviewed witnesses. Data shows that LIWC analysis is an appropriate method to examine witness accounts and, therefore, contributes to a better understanding of the complex relationship between testimony in events under litigation and credibility.
Early ship-based upper-air data and comparison with the Twentieth Century Reanalysis
S. Brnnimann,G. P. Compo,R. Spadin,R. Allan
Climate of the Past Discussions , 2010, DOI: 10.5194/cpd-6-2423-2010
Abstract: Extension of 3-D atmospheric data products back into the past is desirable for a wide range of applications. Historical upper-air data are important in this endeavour, particularly in the maritime regions of the tropics and the southern hemisphere, where observations are extremely sparse. Here we present newly digitized and re-evaluated early ship-based upper-air data from two cruises: (1) kite and registering balloon profiles from onboard the ship SMS Planet on a cruise from Europe around South Africa and across the Indian Ocean to the western Pacific in 1906/1907, and (2) ship-based radiosonde data from onboard the MS Schwabenland on a cruise from Europe across the Atlantic to Antarctica and back in 1938/1939. We describe the data and provide estimations of the errors. We compare the data with a recent reanalysis (the Twentieth Century Reanalysis Project, 20CR, Compo et al., 2010) that provides global 3-D data back to the 19th century based on an assimilation of surface pressure data only (plus monthly mean sea-surface temperatures). In cruise (1), the agreement is generally good, but large temperature differences appear during a period with a strong inversion. In cruise (2), after a correction to a subset of data, a good agreement between observations and 20CR is found for geopotential height (GPH) and temperature except for a likely cold bias of 20CR at the tropopause level. Results are considerably worse for relative humidity, which was reportedly inaccurately measured. Note that comparing 20CR, which has limited skill in the tropical regions, with measurements form ships in remote regions made under sometimes difficult conditions can be considered a worst case assessment. In view of that fact, the anomaly correlations for temperature of 0.3–0.6 in the lower troposphere in cruise (1) and of 0.5–0.7 for tropospheric temperature and GPH in cruise (2) are considered as promising results. Moreover, they are consistent with the error estimations. However, more work is needed for further improving data products in remote regions.
Extreme climate, not extreme weather: the summer of 1816 in Geneva, Switzerland
R. Auchmann,S. Brnnimann,L. Breda,M. Bühler
Climate of the Past Discussions , 2011, DOI: 10.5194/cpd-7-3745-2011
Abstract: We analyze weather and climate during the "Year without Summer" 1816 using sub-daily data from Geneva, Switzerland, representing one of the climatically most severely affected regions. The record includes twice daily measurements and observations of air temperature, pressure, cloud cover, wind speed, and wind direction as well as daily measurements of precipitation. Comparing 1816 to a contemporary reference period (1799–1821) reveals that the coldness of the summer of 1816 was most prominent in the afternoon, with a shift of the entire distribution function of temperature anomalies by 3–4 °C. Early morning temperature anomalies show a smaller change for the mean, a significant decrease in the variability, and no changes in negative extremes. Analyzing cloudy and cloud-free conditions separately suggests that an increase in the number of cloudy days was to a significant extent responsible for these features. A daily weather type classification based on pressure, pressure tendency, and wind direction shows extremely anomalous frequencies in summer 1816, with only one day (compared to 20 in an average summer) classified as high-pressure situation but a tripling of low-pressure situations. The afternoon temperature anomalies expected from only a change in weather types was much stronger negative in summer 1816 than in any other year. For precipitation, our analysis shows that the 80% increase in summer precipitation compared to the reference period can be explained by 80% increase in the frequency of precipitation, while no change could be found neither in the average intensity of precipitation nor in the frequency distribution of extreme precipitation. In all, the analysis shows that the regional circulation and local cloud cover played a dominant role. It also shows that the summer of 1816 was an example of extreme climate, not extreme weather.
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