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Queer to be kind: Exploring Western media discourses about the “Eastern bloc” during the 2007 and 2014 Eurovision Song Contests
This article examines the voting results and Western European media coverage of the 2007 and 2014 Eurovision Song Contests. The Austrian drag act Conchita Wurst (the alter ego of an openly gay man) won in 2014, whilst Serbian entrant Marija Šerifović, portrayed in Western European media as lesbian at the time, won in 2007. We first explore the extent to which there was an East-West voting divide in both contests. In 2014, while there was some elite hostility against Conchita in Eastern Europe, the popular support was on a similar level to that in Western Europe. In 2007, we find no significant geographic divide in support for Šerifović. However, when we examine mainstream UK and German media coverage during and after both contests, we find strong anti-Eastern European discourses that are at odds with the similarity in the public voting. We employ the concept of homonationalism to interrogate inconsistent Western media discourses: the East was depicted as a site of homophobia and the West as a site of tolerance in 2014, whilst the queer aesthetic/identity of Šerifović was largely overlooked in 2007
Ground states and dynamics of population-imbalanced Fermi condensates in one dimension
By using the numerically exact density-matrix renormalization group (DMRG)
approach, we investigate the ground states of harmonically trapped
one-dimensional (1D) fermions with population imbalance and find that the
Larkin-Ovchinnikov (LO) state, which is a condensed state of fermion pairs with
nonzero center-of-mass momentum, is realized for a wide range of parameters.
The phase diagram comprising the two phases of i) an LO state at the trap
center and a balanced condensate at the periphery and ii) an LO state at the
trap center and a pure majority component at the periphery, is obtained. The
reduced two-body density matrix indicates that most of the minority atoms
contribute to the LO-type quasi-condensate. With the time-dependent DMRG, we
also investigate the real-time dynamics of a system of 1D fermions in response
to a spin-flip excitation.Comment: 20 pages, 15 figures, accepted for publication in New Journal of
Physic
A Mechanical Mass Sensor with Yoctogram Resolution
Nanoelectromechanical systems (NEMS) have generated considerable interest as
inertial mass sensors. NEMS resonators have been used to weigh cells,
biomolecules, and gas molecules, creating many new possibilities for biological
and chemical analysis [1-4]. Recently, NEMS-based mass sensors have been
employed as a new tool in surface science in order to study e.g. the phase
transitions or the diffusion of adsorbed atoms on nanoscale objects [5-7]. A
key point in all these experiments is the ability to resolve small masses. Here
we report on mass sensing experiments with a resolution of 1.7 yg (1 yg =
10^-24 g), which corresponds to the mass of one proton, or one hydrogen atom.
The resonator is made of a ~150 nm long carbon nanotube resonator vibrating at
nearly 2 GHz. The unprecedented level of sensitivity allows us to detect
adsorption events of naphthalene molecules (C10H8) and to measure the binding
energy of a Xe atom on the nanotube surface (131 meV). These ultrasensitive
nanotube resonators offer new opportunities for mass spectrometry,
magnetometry, and adsorption experiments.Comment: submitted version of the manuscrip
Acquired demyelination but not genetic developmental defects in myelination leads to brain tissue stiffness changes
Changes in axonal myelination are an important hallmark of aging and a number of neurological diseases. Demyelinated axons are impaired in their function and degenerate over time. Oligodendrocytes, the cells responsible for myelination of axons, are sensitive to mechanical properties of their environment. Growing evidence indicates that mechanical properties of demyelinating lesions are different from the healthy state and thus have the potential to affect myelinating potential of oligodendrocytes. We performed a high-resolution spatial mapping of the mechanical heterogeneity of demyelinating lesions using atomic force microscope-enabled indentation. Our results indicate that the stiffness of specific regions of mouse brain tissue is influenced by age and degree of myelination. Here we specifically demonstrate that acquired acute but not genetic demyelination leads to decreased tissue stiffness, which could influence the remyelination potential of oligodendrocytes. We also demonstrate that specific brain regions have unique ranges of stiffness in white and grey matter. Our ex vivo findings may help the design of future in vitro models to mimic the mechanical environment of the brain in healthy and diseased states. The mechanical properties of demyelinating lesions reported here may facilitate novel approaches in treating demyelinating diseases such as multiple sclerosis
Collision Dynamics and Solvation of Water Molecules in a Liquid Methanol Film
Environmental molecular beam experiments are used to examine water
interactions with liquid methanol films at temperatures from 170 K to 190 K. We
find that water molecules with 0.32 eV incident kinetic energy are efficiently
trapped by the liquid methanol. The scattering process is characterized by an
efficient loss of energy to surface modes with a minor component of the
incident beam that is inelastically scattered. Thermal desorption of water
molecules has a well characterized Arrhenius form with an activation energy of
0.47{\pm}0.11 eV and pre-exponential factor of 4.6 {\times} 10^(15{\pm}3)
s^(-1). We also observe a temperature dependent incorporation of incident water
into the methanol layer. The implication for fundamental studies and
environmental applications is that even an alcohol as simple as methanol can
exhibit complex and temperature dependent surfactant behavior.Comment: 8 pages, 5 figure
Development of superconducting and cryogenic technology in the Institute for Technical Physics (ITP) of the Research Center Karlsruhe
The nature of localization in graphene under quantum Hall conditions
Particle localization is an essential ingredient in quantum Hall physics
[1,2]. In conventional high mobility two-dimensional electron systems Coulomb
interactions were shown to compete with disorder and to play a central role in
particle localization [3]. Here we address the nature of localization in
graphene where the carrier mobility, quantifying the disorder, is two to four
orders of magnitude smaller [4,5,6,7,8,9,10]. We image the electronic density
of states and the localized state spectrum of a graphene flake in the quantum
Hall regime with a scanning single electron transistor [11]. Our microscopic
approach provides direct insight into the nature of localization. Surprisingly,
despite strong disorder, our findings indicate that localization in graphene is
not dominated by single particle physics, but rather by a competition between
the underlying disorder potential and the repulsive Coulomb interaction
responsible for screening.Comment: 18 pages, including 5 figure
Thin Ice Target for O(p,p') experiment
A windowless and self-supporting ice target is described. An ice sheet with a
thickness of 29.7 mg/cm cooled by liquid nitrogen was placed at the target
position of a magnetic spectrometer and worked stably in the O
experiment at MeV. Background-free spectra were obtained.Comment: 14 pages, 4 figures, Nucl. Instr. & Meth. A (in press
Competing Ultrafast Energy Relaxation Pathways in Photoexcited Graphene
For most optoelectronic applications of graphene a thorough understanding of
the processes that govern energy relaxation of photoexcited carriers is
essential. The ultrafast energy relaxation in graphene occurs through two
competing pathways: carrier-carrier scattering -- creating an elevated carrier
temperature -- and optical phonon emission. At present, it is not clear what
determines the dominating relaxation pathway. Here we reach a unifying picture
of the ultrafast energy relaxation by investigating the terahertz
photoconductivity, while varying the Fermi energy, photon energy, and fluence
over a wide range. We find that sufficiently low fluence ( 4
J/cm) in conjunction with sufficiently high Fermi energy (
0.1 eV) gives rise to energy relaxation that is dominated by carrier-carrier
scattering, which leads to efficient carrier heating. Upon increasing the
fluence or decreasing the Fermi energy, the carrier heating efficiency
decreases, presumably due to energy relaxation that becomes increasingly
dominated by phonon emission. Carrier heating through carrier-carrier
scattering accounts for the negative photoconductivity for doped graphene
observed at terahertz frequencies. We present a simple model that reproduces
the data for a wide range of Fermi levels and excitation energies, and allows
us to qualitatively assess how the branching ratio between the two distinct
relaxation pathways depends on excitation fluence and Fermi energy.Comment: Nano Letters 201
Immediate effects of ammonia shock on transcription and composition of a biogas reactor microbiome
The biotechnological process of biogas production from organic material is carried out by a diverse microbial community under anaerobic conditions. However, the complex and sensitive microbial network present in anaerobic degradation of organic material can be disturbed by increased ammonia concentration introduced into the system by protein-rich substrates and imbalanced feeding. Here, we report on a simulated increase of ammonia concentration in a fed batch lab-scale biogas reactor experiment. Two treatment conditions were used simulating total ammonia nitrogen concentrations of 4.9 and 8.0 g/L with four replicate reactors. Each reactor was monitored concerning methane generation and microbial composition using 16S rRNA gene amplicon sequencing, while the transcriptional activity of the overall process was investigated by metatranscriptomic analysis. This allowed investigating the response of the microbial community in terms of species composition and transcriptional activity to a rapid upshift to high ammonia conditions. Clostridia and Methanomicrobiales dominated the microbial community throughout the entire experiment under both experimental conditions, while Methanosarcinales were only present in minor abundance. Transcription analysis demonstrated clostridial dominance with respect to genes encoding for enzymes of the hydrolysis step (cellulase, EC 3.2.1.4) as well as dominance of key genes for enzymes of the methanogenic pathway (methyl-CoM reductase, EC 2.8.4.1; heterodisulfide reductase, EC 1.8.98.1). Upon ammonia shock, the selected marker genes showed significant changes in transcriptional activity. Cellulose hydrolysis as well as methanogenesis were significantly reduced at high ammonia concentrations as indicated by reduced transcription levels of the corresponding genes. Based on these experiments we concluded that, apart from the methanogenic archaea, hydrolytic cellulose-degrading microorganisms are negatively affected by high ammonia concentrations. Further, Acholeplasma and Erysipelotrichia showed lower abundance under increased ammonia concentrations and thus might serve as indicator species for an earlier detection in order to counteract against ammonia crises. © Copyright © 2019 Fischer, Ulbricht, Neulinger, Refai, Waßmann, Künzel and Schmitz
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