936 research outputs found
Shock-wave therapy of gastric outlet syndrome caused by a gallstone
A patient with gastric outlet syndrome (Bouveret's syndrome) caused by a large gallstone impacted in the duodenal bulb was successfully treated by extracorporeal shock-wave lithotripsy. Thus, open abdominal surgery could be avoided. For disintegration of the stone, three consecutive lithotripsy procedures were necessary. Thereafter, stone fragments could be extracted endoscopically. Extracorporeal shock-wave lithotripsy could become a non-surgical alternative in patients with obstruction of the duodenum caused by a gallstone
Metabasites from the KTB Oberpfalz target area, Bavaria - geochemical characteristics and examples of mobile behaviour of "immobile" elements
No abstract availabl
Molecular Basis for poly(A) RNP Architecture and Recognition by the Pan2-Pan3 Deadenylase
The stability of eukaryotic mRNAs is dependent on a ribonucleoprotein (RNP) complex of poly(A)-binding proteins (PABPC1/Pab1) organized on the poly(A) tail. This poly(A) RNP not only protects mRNAs from premature degradation but also stimulates the Pan2-Pan3 deadenylase complex to catalyze the first step of poly(A) tail shortening. We reconstituted this process in vitro using recombinant proteins and show that Pan2-Pan3 associates with and degrades poly(A) RNPs containing two or more Pab1 molecules. The cryo-EM structure of Pan2-Pan3 in complex with a poly(A) RNP composed of 90 adenosines and three Pab1 protomers shows how the oligomerization interfaces of Pab1 are recognized by conserved features of the deadenylase and thread the poly(A) RNA substrate into the nuclease active site. The structure reveals the basis for the periodic repeating architecture at the 3' end of cytoplasmic mRNAs. This illustrates mechanistically how RNA-bound Pab1 oligomers act as rulers for poly(A) tail length over the mRNAs' lifetime.We would like to thank ... the MPIB cryo-EM, and core facilities ..
An analytic interface dynamo over a shear layer of finite depth
Parker's analytic Cartesian interface dynamo is generalized to the case of a
shear layer of finite thickness and low resistivity ("tachocline"), bounded by
a perfect conductor ("radiative zone") on the one side, and by a highly
diffusive medium ("convective zone") supporting an -effect on the other
side. In the limit of high diffusivity contrast between the shear layer and the
diffusive medium, thought to be relevant for the Sun, a pair of exact
dispersion relations for the growth rate and frequency of dynamo modes is
analytically derived. Graphic solution of the dispersion relations displays a
somewhat unexpected, non-monotonic behaviour, the mathematical origin of which
is elucidated. The dependence of the results on the parameter values (dynamo
number and shear layer thickness) is investigated. The implications of this
result for the solar dynamo problem are discussed.Comment: 11 pages, 4 figures Geophys. Astrophys. Fluid Dyn., in pres
News, macroeconomic expectations and disagreement
An increasing amount of research focuses on the e↵ects of news and uncertainty on macroeconomic aggregates. Although it is widely agreed that uncertainty exhibits various transmission channels with regard to the real economy and financial markets, little is known about the e↵ects of economic news on macroeconomic and financial expectations.
Quantifying textual data has become popular in recent years to, for example, construct uncertainty measures such as the Economic Policy Uncertainty Index.
Major advances in natural language processing, however, have made it feasible to quantify vast amounts of written texts without relying on pre-determined keywords or manual compilations. We combine a correlated topic model [4] and a dictionary based sentiment analysis to extract economic topics from approx. 500,000 U.S.
newspaper articles. The results are used to investigate which type of news is correlated with professional economic forecasts and whether such impact is varying over time. The newspaper articles are obtained from LexisNexis Group and the survey data from Consensus Economics.
The text analysis is entirely conducted with R and relies on powerful packages such as dplyr, quanteda and stm. The econometric analysis uses a flexible version of dynamic model averaging for which the code is written in Matlab.Sociedad Argentina de Informática e Investigación Operativ
The H.E.S.S. multi-messenger program
Based on fundamental particle physics processes like the production and
subsequent decay of pions in interactions of high-energy particles, close
connections exist between the acceleration sites of high-energy cosmic rays and
the emission of high-energy gamma rays and high-energy neutrinos. In most cases
these connections provide both spatial and temporal correlations of the
different emitted particles. The combination of the complementary information
provided by these messengers allows to lift ambiguities in the interpretation
of the data and enables novel and highly sensitive analyses. In this
contribution the H.E.S.S. multi-messenger program is introduced and described.
The current core of this newly installed program is the combination of
high-energy neutrinos and high-energy gamma rays. The search for gamma-ray
emission following gravitational wave triggers is also discussed. Furthermore,
the existing program for following triggers in the electromagnetic regime was
extended by the search for gamma-ray emission from Fast Radio Bursts (FRBs). An
overview over current and planned analyses is given and recent results are
presented.Comment: In Proceedings of the 34th International Cosmic Ray Conference
(ICRC2015), The Hague, The Netherland
Simultaneous H.E.S.S. and RXTE observations of the microquasars GRS 1915+105, Circinus X-1 and V4641 Sgr
Microquasars, Galactic binary systems showing extended and variable radio emission, are potential gamma-ray emitters. Indications of gamma-ray transient episodes have been reported in at least two systems, Cyg X-1 and Cyg X-3. The identification of additional gamma-ray emitting microquasars is key for a better understanding of these systems. Very-high-energy gamma-ray emission from microquasars has been predicted to happen during periods of transient outbursts potentially connected with the formation of a jet-like outflow. Contemporaneous observations using the H.E.S.S. telescope array and the RXTE satellite were obtained on three microquasars: GRS 1915+105, Circinus X-1 and V4641 Sgr with the aim of detecting a broadband flaring event in the very-high-energy gamma-ray and X-ray bands. We report here on the analysis of these data for each system, including a detailed X-ray analysis assessing the location of the sources in a hardness-intensity diagram during the observations. Finally we discuss the derived upper limits on their very-high-energy gamma-ray flux
Umbral Dynamics in the Near Infrared Continuum
We detected peaks of oscillatory power at 3 and ~6.5 minutes in the umbra of
the central sunspot of the active region NOAA AR 10707 in data obtained in the
near infrared (NIR) continuum at 1565.7 nm. The NIR dataset captured umbral
dynamics around 50 km below the photospheric level. The umbra does not
oscillate as a whole, but rather in distinct parts that are distributed over
the umbral surface. The most powerful oscillations, close to a period of ~ 6.5,
do not propagate upward. We noted a plethora of large umbral dots that
persisted for more than 30 minutes and stayed in the same locations. The peaks
of oscillatory power above the detected umbral dots are located at 3 and 5
minutes oscillations, but are very weak in comparison with the oscillations of
~ 6.5 minutes.Comment: 16 pages, 8 figures, accepted in Ap
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