4,906 research outputs found
Historical “Truth,” Constructed Memory: Restaging Germany’s Reunification in Thomas Berger’s Television Melodrama Wir sind das Volk. Liebe kennt keine Grenzen (We are the people. Love without limits) (2008)
Film and television are popular media for the (re)presentation of history and the depiction of momentous past events. Germany’s reunification is no exception. After the fall of the Berlin Wall, Germany has witnessed a proliferation of media production that endeavors to historicize and aestheticize the past. This coincides with the need to forge a post-Wall identity of the new Germany. My discussion of Thomas Berger’s award winning television drama Wir sind das Volk. Liebe kennt keine Grenzen (2008) examines how reunification is presented in a mixture of fictitious elements and authentic historical reconstruction based on shared memories of this past. Following a melodramatic trajectory, the film aims at the reconciliation of German society as a people twenty years after reunification
Some tree-level string amplitudes in the NSR formalism
We calculate tree level scattering amplitudes for open strings using the NSR
formalism. We present a streamlined symmetry-based and pedagogical approach to
the computations, which we first develop by checking two-, three-, and
four-point functions involving bosons and fermions. We calculate the five-point
amplitude for massless gluons and find agreement with an earlier result by
Brandt, Machado and Medina. We then compute the five-point amplitudes involving
two and four fermions respectively, the general form of which has not been
previously obtained in the NSR formalism. The results nicely confirm
expectations from the supersymmetric effective action. Finally we use the
prescription of Kawai, Lewellen and Tye (KLT) to compute the amplitudes for the
closed string sector.Comment: 40+8 pages; v2: references added; v3: additional field theory checks
made; published version; v4: minor corrections; results unchange
English-learning infants’ perception of word stress patterns
Adult speakers of different free stress languages (e.g., English, Spanish) differ both in their sensitivity to lexical stress and in their processing of suprasegmental and vowel quality cues to stress. In a head-turn preference experiment with a familiarization phase, both 8-month-old and 12-month-old English-learning infants discriminated between initial stress and final stress among lists of Spanish-spoken disyllabic nonwords that were segmentally varied (e.g. [ˈnila, ˈtuli] vs [luˈta, puˈki]). This is evidence that English-learning infants are sensitive to lexical stress patterns, instantiated primarily by suprasegmental cues, during the second half of the first year of life
Marktchancen für unternutzte Getreidearten in Bio-Bäckereien: Das Beispiel von Emmer, Einkorn und Dinkel
Weizen dominiert die Getreideanbauflächen in Europa. Roggen, Hafer, Dinkel, Emmer und Einkorn werden deutlich weniger angebaut. Diese Getreidesorten haben jedoch Eigenschaften, die sie heute für den ökologischen Anbau und den Konsum interessant machen: Sie sind gut verträglich, haben einen eigenen Geschmack, wachsen auch in extensiven Anbausystemen gut und sind an verschiedene Klimabedingungen angepasst. Im Rahmen einer Untersuchung von 11 Bäckereien mit Bio-Sortiment in Deutschland und der Schweiz konnte ein Marktpotenzial diese Getreidesorten in Bäckereien festgestellt werden. Ein Teil der Bäckereien sieht die Marktchancen eher positiv während andere Betriebe darauf hinwiesen, dass die Verarbeitung dieser alten Sorten schwierig und aufwändig sei und die Marktchancen daher gering. Die Bio-Bäcker gehen davon aus, dass die Getreide in einem Nischenmarkt bleiben und Weizen nicht ersetzen werden. Wichtig scheint auch die Einbindung von Mühlen und Landwirten sowie eine geeignete Kommunikation bei den Konsumenten. Die befragten Bäckereien bewerben ihre Produkte eher mit Geschmack und Gesundheit als mit Biodiversität, Nachhaltigkeit und Regionalität. Gerade für Bio-Bäckereien könnte die Verbindung von Umweltargumenten, regionaler Herkunft und traditioneller Verarbeitung jedoch eine Marktchance bedeuten. Um den Marktanteil der alten Getreidesorten zu erhöhen scheint es unverzichtbar, auch die Mühlen vom Mehrwert dieser Produkte zu überzeugen. Müssen die Getreide weite Strecken zu einer Mühle transportiert werden, ist die Argumentation hinsichtlich Regionalität in den Bäckereien nicht glaubwürdig. Bäckereien sind jedoch geeignete Orte, um den Mehrwert der Produkte zu kommunizieren.
Die Arbeit konnte im Rahmen des EU Projekt HealthyMinorCereals durchgeführt werden
The protein tyrosine kinases EpsB and PtkA differentially affect biofilm formation in <em>Bacillus subtilis</em>
The Gram-positive soil bacterium Bacillus subtilis is able to choose between motile and sessile lifestyles. The sessile way of life, also referred to as biofilm, depends on the formation of an extracellular polysaccharide matrix and some extracellular proteins. Moreover, a significant proportion of cells in a biofilm form spores. The first two genes of the 15-gene operon for extracellular polysaccharide synthesis, epsA and epsB, encode a putative transmembrane modulator protein and a putative protein tyrosine kinase, respectively, with similarity to the TkmA/PtkA modulator/kinase couple. Here we show that the putative kinase EpsB is required for the formation of structured biofilms. However, an epsB mutant is still able to form biofilms. As shown previously, a ptkA mutant is also partially defective in biofilm formation, but this defect is related to spore formation in the biofilm. The absence of both kinases resulted in a complete loss of biofilm formation. Thus, EpsB and PtkA fulfil complementary functions in biofilm formation. The activity of bacterial protein tyrosine kinases depends on their interaction with modulator proteins. Our results demonstrate the specific interaction between the putative kinase EpsB and its modulator protein EpsA and suggest that EpsB activity is stimulated by its modulator EpsA
Robustness of Cosmological Simulations I: Large Scale Structure
The gravitationally-driven evolution of cold dark matter dominates the
formation of structure in the Universe over a wide range of length scales.
While the longest scales can be treated by perturbation theory, a fully
quantitative understanding of nonlinear effects requires the application of
large-scale particle simulation methods. Additionally, precision predictions
for next-generation observations, such as weak gravitational lensing, can only
be obtained from numerical simulations. In this paper, we compare results from
several N-body codes using test problems and a diverse set of diagnostics,
focusing on a medium resolution regime appropriate for studying many
observationally relevant aspects of structure formation. Our conclusions are
that -- despite the use of different algorithms and error-control methodologies
-- overall, the codes yield consistent results. The agreement over a wide range
of scales for the cosmological tests is test-dependent. In the best cases, it
is at the 5% level or better, however, for other cases it can be significantly
larger than 10%. These include the halo mass function at low masses and the
mass power spectrum at small scales. While there exist explanations for most of
the discrepancies, our results point to the need for significant improvement in
N-body errors and their understanding to match the precision of near-future
observations. The simulation results, including halo catalogs, and initial
conditions used, are publicly available.Comment: 32 pages, 53 figures, data from the simulations is available at
http://t8web.lanl.gov/people/heitmann/arxiv, accepted for publication in
ApJS, several minor revisions, reference added, main conclusions unchange
Cosmological implications of the KATRIN experiment
The upcoming Karlsruhe Tritium Neutrino (KATRIN) experiment will put
unprecedented constraints on the absolute mass of the electron neutrino,
\mnue. In this paper we investigate how this information on \mnue will
affect our constraints on cosmological parameters. We consider two scenarios;
one where \mnue=0 (i.e., no detection by KATRIN), and one where
\mnue=0.3eV. We find that the constraints on \mnue from KATRIN will affect
estimates of some important cosmological parameters significantly. For example,
the significance of and the inferred value of depend
on the results from the KATRIN experiment.Comment: 13 page
The Halo Mass Function: High-Redshift Evolution and Universality
We study the formation of dark matter halos in the concordance LCDM model
over a wide range of redshifts, from z=20 to the present. Our primary focus is
the halo mass function, a key probe of cosmology. By performing a large suite
of nested-box N-body simulations with careful convergence and error controls
(60 simulations with box sizes from 4 to 256 Mpc/h, we determine the mass
function and its evolution with excellent statistical and systematic errors,
reaching a few percent over most of the considered redshift and mass range.
Across the studied redshifts, the halo mass is probed over 6 orders of
magnitude (10^7 - 10^13.5 M_sun/h). Historically, there has been considerable
variation in the high redshift mass function as obtained by different groups.
We have made a concerted effort to identify and correct possible systematic
errors in computing the mass function at high redshift and to explain the
discrepancies between some of the previous results. We discuss convergence
criteria for the required force resolution, simulation box size, halo mass
range, initial and final redshift, and time stepping. Because of conservative
cuts on the mass range probed by individual boxes, our results are relatively
insensitive to simulation volume, the remaining sensitivity being consistent
with extended Press-Schechter theory. Previously obtained mass function fits
near z=0, when scaled by linear theory, are in good agreement with our results
at all redshifts, although a mild redshift dependence consistent with that
found by Reed and collaborators exists at low redshifts.Comment: 20 pages, 15 figures. Minor changes to the text and figures; results
and conclusions unchange
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