430 research outputs found
pyrG of Aspergillus nidulans, meiotic mapping, marker interactions and growth response
Information of the genetic location of pyrG and its growth response under various conditions has become important with the recent cloning of pyrG (Oakley et al. 1987. Gene 61:385-399) and with the use of pyrG strains as recipients for transformation when pyr-4 cloning vectors are used for A. nidulans libraries (e.g. May et al. 1985 J. Cell Biol. 101:712-719 ; Osmani et al. 1987 J. Cell Biol. 104:1495-1504)
Pre-rehabilitation sense of coherence as a predictor of symptom change after rehabilitation
Sense of coherence (SOC) constitutes the key component of salutogenesis theory. It reflects individuals' confidence that their environment is comprehensible and manageable and that their lives are meaningful. Research demonstrates a strong cross-sectional relationship between SOC and mental health. However, little is known about SOC's temporal stability and its potential to predict changes in psychopathological symptom severity in different settings. The goal of the current study was to address this gap. The sample of the two-wave longitudinal study consists of 294 patients receiving inpatient psychotherapeutic (and psychopharmacological) treatment for various psychological disorders at a German psychosomatic rehabilitation clinic. SOC (Antonovsky, Social Science & Medicine, 1993, 36, 725-733) and outcome measures (i.e., general mental health problems, depression and anxiety symptoms) were assessed within two days of arrival and at the end of rehabilitation (week 5/6). SOC was significantly enhanced after treatment whereas psychopathological symptoms were significantly reduced. Regression analyses revealed that pre-treatment SOC was a significant negative predictor of post-treatment symptom severity for all outcome measures even after controlling for pre-treatment symptoms. The current findings provide first evidence that SOC is a significant unique predictor of symptom change. Future studies need to further investigate longitudinal associations between SOC and mental health outcomes in different settings
Influence of steps on the tilting and adsorption dynamics of ordered Pn films on vicinal Ag(111) surfaces
Here we present a structural study of pentacene (Pn) thin films on vicinal
Ag(111) surfaces by He atom diffraction measurements and density functional
theory (DFT) calculations supplemented with van der Waals (vdW) interactions.
Our He atom diffraction results suggest initial adsorption at the step edges
evidenced by initial slow specular reflection intensity decay rate as a
function of Pn deposition time. In parallel with the experimental findings, our
DFT+vdW calculations predict the step edges as the most stable adsorption site
on the surface. An isolated molecule adsorbs as tilted on the step edge with a
binding energy of 1.4 eV. In addition, a complete monolayer (ML) with
pentacenes flat on the terraces and tilted only at the step edges is found to
be more stable than one with all lying flat or tilted molecules, which in turn
influences multilayers. Hence our results suggest that step edges can trap Pn
molecules and act as nucleation sites for the growth of ordered thin films with
a crystal structure similar to that of bulk Pn.Comment: 4 pages, 4 figures, 1 tabl
Bilateral proximal tibia fracture
A bilateral fracture of the proximal tibia is rare in children. We describe a girl with a bilateral fracture just distal of the epiphyseal plate after minimal trauma
Chronic y-secretase inhibition reduces amyloid plaque-associated instability of pre- and postsynaptic structures
The loss of synapses is a strong histological correlate of the cognitive decline in Alzheimer’s disease (AD). Amyloid bpeptide (Ab), a cleavage product of the amyloid precursor protein (APP), exerts detrimental effects on synapses, a process thought to be causally related to the cognitive deficits in AD. Here, we used in vivo two-photon microscopy to characterize the dynamics of axonal boutons and dendritic spines in APP/Presenilin 1 (APPswe/PS1L166P)–green fluorescent protein (GFP) transgenic mice. Time-lapse imaging over 4 weeks revealed a pronounced, concerted instability of pre- and postsynaptic structures within the vicinity of amyloid plaques. Treatment with a novel sulfonamide-type g-secretase inhibitor (GSI) attenuated the formation and growth of new plaques and, most importantly, led to a normalization of the enhanced dynamics of synaptic structures close to plaques. GSI treatment did neither affect spines and boutons distant from plaques in amyloid precursor protein/presenilin 1-GFP (APPPS1-GFP) nor those in GFP-control mice, suggesting no obvious neuropathological side effects of the drug
Synthetic simulations of the extragalactic sky seen by eROSITA I. Pre-launch selection functions from Monte-Carlo simulations
Context. Studies of galaxy clusters provide stringent constraints on models of structure formation. Provided that selection effects are under control, large X-ray surveys are well suited to derive cosmological parameters, in particular those governing the dark energy equation of state. Aims. We forecast the capabilities of the all-sky eROSITA (extended ROentgen Survey with an Imaging Telescope Array) survey to be achieved by the early 2020s. We bring special attention to modelling the entire chain from photon emission to source detection and cataloguing. Methods. The selection function of galaxy clusters for the upcoming eROSITA mission is investigated by means of extensive and dedicated Monte-Carlo simulations. Employing a combination of accurate instrument characterisation and a state-of-the-art source detection technique, we determine a cluster detection efficiency based on the cluster fluxes and sizes. Results. Using this eROSITA cluster selection function, we find that eROSITA will detect a total of approximately 10(5) clusters in the extra-galactic sky. This number of clusters will allow eROSITA to put stringent constraints on cosmological models. We show that incomplete assumptions on selection effects, such as neglecting the distribution of cluster sizes, induce a bias in the derived value of cosmological parameters. Conclusions. Synthetic simulations of the eROSITA sky capture the essential characteristics impacting the next-generation galaxy cluster surveys and they highlight parameters requiring tight monitoring in order to avoid biases in cosmological analyses.Peer reviewe
Monitoring of the operating parameters of the KATRIN Windowless Gaseous Tritium Source
The Karlsruhe Tritium Neutrino (KATRIN) experiment will measure the absolute
mass scale of neutrinos with a sensitivity of \m_{\nu} = 200 meV/c by
high-precision spectroscopy close to the tritium beta-decay endpoint at 18.6
keV. Its Windowless Gaseous Tritium Source (WGTS) is a beta-decay source of
high intensity (/s) and stability, where high-purity molecular tritium
at 30 K is circulated in a closed loop with a yearly throughput of 10 kg. To
limit systematic effects the column density of the source has to be stabilised
at the 0.1% level. This requires extensive sensor instrumentation and dedicated
control and monitoring systems for parameters such as the beam tube
temperature, injection pressure, gas composition and others. Here we give an
overview of these systems including a dedicated Laser-Raman system as well as
several beta-decay activity monitors. We also report on results of the WGTS
demonstrator and other large-scale test experiments giving proof-of-principle
that all parameters relevant to the systematics can be controlled and monitored
on the 0.1% level or better. As a result of these works, the WGTS systematics
can be controlled within stringent margins, enabling the KATRIN experiment to
explore the neutrino mass scale with the design sensitivity.Comment: 32 pages, 13 figures. modification to title, typos correcte
Lambda and Sigma0 Pair Production in Two-Photon Collisions at LEP
Strange baryon pair production in two-photon collisions is studied with the
L3 detector at LEP. The analysis is based on data collected at e+e-
centre-of-mass energies from 91 GeV to 208 GeV, corresponding to an integrated
luminosity of 844 pb-1. The processes gamma gamma -> Lambda Anti-lambda and
gamma gamma -> Sigma0 Anti-sigma0 are identified. Their cross sections as a
function of the gamma gamma centre-of-mass energy are measured and results are
compared to predictions of the quark-diquark model
Measurement of W Polarisation at LEP
The three different helicity states of W bosons produced in the reaction e+
e- -> W+ W- -> l nu q q~ at LEP are studied using leptonic and hadronic W
decays. Data at centre-of-mass energies \sqrt s = 183-209 GeV are used to
measure the polarisation of W bosons, and its dependence on the W boson
production angle. The fraction of longitudinally polarised W bosons is measured
to be 0.218 \pm 0.027 \pm 0.016 where the first uncertainty is statistical and
the second systematic, in agreement with the Standard Model expectation
Bose-Einstein Correlations of Neutral and Charged Pions in Hadronic Z Decays
Bose-Einstein correlations of both neutral and like-sign charged pion pairs
are measured in a sample of 2 million hadronic Z decays collected with the L3
detector at LEP. The analysis is performed in the four-momentum difference
range 300 MeV < Q < 2 GeV. The radius of the neutral pion source is found to be
smaller than that of charged pions. This result is in qualitative agreement
with the string fragmentation model
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