48 research outputs found
The MIGenAS integrated bioinformatics toolkit for web-based sequence analysis
We describe a versatile and extensible integrated bioinformatics toolkit for the analysis of biological sequences over the Internet. The web portal offers convenient interactive access to a growing pool of chainable bioinformatics software tools and databases that are centrally installed and maintained by the RZG. Currently, supported tasks comprise sequence similarity searches in public or user-supplied databases, computation and validation of multiple sequence alignments, phylogenetic analysis and protein–structure prediction. Individual tools can be seamlessly chained into pipelines allowing the user to conveniently process complex workflows without the necessity to take care of any format conversions or tedious parsing of intermediate results. The toolkit is part of the Max-Planck Integrated Gene Analysis System (MIGenAS) of the Max Planck Society available at (click ‘Start Toolkit’)
Spherically Symmetric Simulation with Boltzmann Neutrino Transport of Core Collapse and Post-Bounce Evolution of a 15 Solar Mass Star
We present a spherically symmetric, Newtonian core-collapse simulation of a
15 solar mass star with a 1.28 solar mass iron core. The time-, energy-, and
angle-dependent transport of electron neutrinos and antineutrinos was treated
with a new code which iteratively solves the Boltzmann equation and the
equations for neutrino number, energy and momentum to order O(v/c) in the
velocity v of the stellar medium. The supernova shock expands to a maximum
radius of 350 km instead of only about 240 km as in a comparable calculation
with multi-group flux-limited diffusion (MGFLD) by Bruenn, Mezzacappa, & Dineva
(1995). This may be explained by stronger neutrino heating due to the more
accurate transport in our model. Nevertheless, after 180 ms of expansion the
shock finally recedes to a radius around 250 km (compared to about 170 km in
the MGFLD run). The effect of an accurate neutrino transport is helpful, but
not large enough to cause an explosion of the considered 15 solar mass star.
Therefore postshock convection and/or an enhancement of the core neutrino
luminosity by convection or reduced neutrino opacities in the neutron star seem
necessary for neutrino-driven explosions of such stars. We find an electron
fraction Y_e > 0.5 in the neutrino-heated matter, which suggests that the
overproduction problem of neutron-rich nuclei with mass numbers around A = 90
in exploding models may be absent when a Boltzmann solver is used for the
electron neutrino and antineutrino transport.Comment: 6 pages, LaTex, 3 encapsulated postscript figures, revised and
shortened version. Astrophys. J., Letters, accepte
General-Relativistic MHD for the Numerical Construction of Dynamical Spacetimes
We assemble the equations of general relativistic magnetohydrodynamics (MHD)
in 3+1 form. These consist of the complete coupled set of Maxwell equations for
the electromagnetic field, Einstein's equations for the gravitational field,
and the equations of relativistic MHD for a perfectly conducting ideal gas. The
adopted form of the equations is suitable for evolving numerically a
relativistic MHD fluid in a dynamical spacetime characterized by a strong
gravitational field.Comment: 8 pages; scheduled for March 10 issue of Ap
Electron Neutrino Pair Annihilation: A New Source for Muon and Tau Neutrinos in Supernovae
We show that in a supernova core the annihilation process nu_e nu_e-bar ->
nu_{mu,tau} nu_{mu,tau}-bar is always more important than the traditional
reaction e^+ e^- -> nu_{mu,tau} nu_{mu,tau}-bar as a source for muon and tau
neutrino pairs. We study the impact of the new process by means of a Monte
Carlo transport code with a static stellar background model and by means of a
self-consistent hydrodynamical simulation with Boltzmann neutrino transport.
Nucleon bremsstrahlung NN -> NN nu_{mu,tau} nu_{mu,tau}-bar is also included as
another important source term. Taking into account nu_e nu_e-bar -> nu_{mu,tau}
nu_{mu,tau}-bar increases the nu_mu and nu_tau luminosities by as much as 20%
while the spectra remain almost unaffected. In our hydrodynamical simulation
the shock was somewhat weakened. Elastic nu_{mu,tau} nu_e and nu_{mu,tau} nu_e
scattering is not negligible but less important than nu_{mu,tau} e^+ or e^-
scattering. Its influence on the nu_{mu,tau} fluxes and spectra is small after
all other processes have been included.Comment: 11 pages, 9 eps-figs, submitted to Ap
Towards Gravitational Wave Signals from Realistic Core Collapse Supernova Models
We have computed the gravitational wave signal from supernova core collapse
using the presently most realistic input physics available. We start from
state-of-the-art progenitor models of rotating and non-rotating massive stars,
and simulate the dynamics of their core collapse by integrating the equations
of axisymmetric hydrodynamics together with the Boltzmann equation for the
neutrino transport including an elaborate description of neutrino interactions,
and a realistic equation of state. We compute the quadrupole wave amplitudes,
the Fourier wave spectra, the amount of energy radiated in form of
gravitational waves, and the S/N ratios for the LIGO and the tuned Advanced
LIGO interferometers resulting both from non-radial mass motion and anisotropic
neutrino emission. The simulations demonstrate that the dominant contribution
to the gravitational wave signal is produced by neutrino-driven convection
behind the supernova shock. For stellar cores rotating at the extreme of
current stellar evolution predictions, the core-bounce signal is detectable
with advanced LIGO up to a distance of 5kpc, whereas the signal from post-shock
convection is observable up to a distance of about 100kpc. If the core is
non-rotating its gravitational wave emission can be measured up to a distance
of 15kpc, while the signal from the Ledoux convection in the deleptonizing,
nascent neutron star can be detected up to a distance of 10kpc. Both kinds of
signals are generically produced by convection in any core collapse supernova.Comment: 9 pages, 13 figures, Latex, submitted to ApJ, error in ps-file fixed;
figures in full resolution are available upon reques
Genome information management and integrated data analysis with HaloLex
HaloLex is a software system for the central management, integration, curation, and web-based visualization of genomic and other -omics data for any given microorganism. The system has been employed for the manual curation of three haloarchaeal genomes, namely Halobacterium salinarum (strain R1), Natronomonas pharaonis, and Haloquadratum walsbyi. HaloLex, in particular, enables the integrated analysis of genome-wide proteomic results with the underlying genomic data. This has proven indispensable to generate reliable gene predictions for GC-rich genomes, which, due to their characteristically low abundance of stop codons, are known to be hard targets for standard gene finders, especially concerning start codon assignment. The proteomic identification of more than 600 N-terminal peptides has greatly increased the reliability of the start codon assignment for Halobacterium salinarum. Application of homology-based methods to the published genome of Haloarcula marismortui allowed to detect 47 previously unidentified genes (a problem that is particularly serious for short protein sequences) and to correct more than 300 start codon misassignments
The bar-mode instability in differentially rotating neutron stars: Simulations in full general relativity
We study the dynamical stability against bar-mode deformation of rapidly
spinning neutron stars with differential rotation. We perform fully
relativistic 3D simulations of compact stars with , where is
the total gravitational mass and the equatorial circumferential radius. We
adopt an adiabatic equation of state with adiabatic index . As in
Newtonian theory, we find that stars above a critical value of (where is the rotational kinetic energy and the gravitational
binding energy) are dynamically unstable to bar formation. For our adopted
choices of stellar compaction and rotation profile, the critical value of
is , only slightly smaller than the
well-known Newtonian value for incompressible Maclaurin spheroids.
The critical value depends only very weakly on the degree of differential
rotation for the moderate range we surveyed. All unstable stars form bars on a
dynamical timescale. Models with sufficiently large subsequently form
spiral arms and eject mass, driving the remnant to a dynamically stable state.
Models with moderately large do not develop spiral
arms or eject mass but adjust to form dynamically stable ellipsoidal-like
configurations. If the bar-mode instability is triggered in supernovae collapse
or binary neutron star mergers, it could be a strong and observable source of
gravitational waves. We determine characteristic wave amplitudes and
frequencies.Comment: 17 pages, accepted for publication in AP
Isolated and Combined Effects of Electroacupuncture and Meditation in Reducing Experimentally Induced Ischemic Pain: A Pilot Study
Acupuncture and meditation are promising treatment options for clinical pain. However, studies investigating the effects of these methods on experimental pain conditions are equivocal. Here, the effects of electroacupuncture (EA) and meditation on the submaximum effort tourniquet technique (SETT), a well-established, opiate-sensitive pain paradigm in experimental placebo research were studied. Ten experienced meditators (6 male subjects) and 13 nonmeditators (6 male subjects) were subjected to SETT (250 mmHG) on one baseline (SETT only) and two treatment days (additional EA contralaterally to the SETT, either at the leg on ST36 and LV3 or at the arm on LI4 and LI10 in randomized order). Numeric Rating Scale (NRS) ratings (scale 0–10) were recorded every 3 min. During baseline, meditation induced significantly greater pain tolerance in meditators when compared with the control group. Both the EA conditions significantly increased pain tolerance and reduced pain ratings in controls. Furthermore, EA diminished the group difference in pain sensitivity, indicating that meditators had no additional benefit from acupuncture. The data suggest that EA as a presumable bottom-up process may be as effective as meditation in controlling experimental SETT pain. However, no combined effect of both the techniques could be observed
The influence of a series of five dry cupping treatments on pain and mechanical thresholds in patients with chronic non-specific neck pain : a randomised controlled pilot study
In this preliminary trial we investigated the effects of dry cupping, an ancient method for treating pain syndromes, on patients with chronic non-specific neck pain. Sensory mechanical thresholds and the participants’ self-reported outcome measures of pain and quality of life were evaluated.
Fifty patients (50.5 ± 11.9 years) were randomised to a treatment group (TG) or a waiting-list control group (WL). Patients in the TG received a series of 5 cupping treatments over a period of 2 weeks; the control group did not. Self-reported outcome measures before and after the cupping series included the following: Pain at
rest (PR) and maximal pain related to movement (PM) on a 100-mm visual analogue scale (VAS), pain diary (PD) data on a 0-10 numeric rating scale (NRS), Neck Disability Index (NDI), and health-related quality of life (SF-36). In
addition, the mechanical-detection thresholds (MDT), vibration-detection thresholds (VDT), and pressure-pain thresholds (PPT) were determined at pain-related and control areas.
Patients of the TG had significantly less pain after cupping therapy than patients of the WL group (PR: Δ-22.5 mm, p = 0.00002; PM: Δ-17.8 mm, p = 0.01). Pain diaries (PD) revealed that neck pain decreased gradually in the TG patients and that pain reported by the two groups differed significantly after the fifth cupping session
(Δ-1.1, p = 0.001). There were also significant differences in the SF-36 subscales for bodily pain (Δ13.8, p = 0.006) and vitality (Δ10.2, p = 0.006). Group differences in PPT were significant at pain-related and control areas (all p < 0.05), but were not significant for MDT or VDT.
A series of five dry cupping treatments appeared to be effective in relieving chronic non-specific
neck pain. Not only subjective measures improved, but also mechanical pain sensitivity differed significantly between the two groups, suggesting that cupping has an influence on functional pain processing
The Effect of Traditional Cupping on Pain and Mechanical Thresholds in Patients with Chronic Nonspecific Neck Pain: A Randomised Controlled Pilot Study
Introduction. Cupping has been used since antiquity in the treatment of pain conditions. In this pilot study, we investigated the effect of traditional cupping therapy on chronic nonspecific neck pain (CNP) and mechanical sensory thresholds. Methods. Fifty CNP patients were randomly assigned to treatment (TG, n = 25) or waiting list control group (WL, n = 25). TG received a single cupping treatment. Pain at rest (PR), pain related to movement (PM), quality of life (SF-36), Neck Disability Index (NDI), mechanical detection (MDT), vibration detection (MDT), and pressure pain thresholds (PPT) were measured before and three days after a single cupping treatment. Patients also kept a pain and medication diary (PaDi, MeDi) during the study. Results. Baseline characteristics were similar in the two groups. After cupping TG reported significantly less pain (PR: −17.9 mm VAS, 95%CI −29.2 to −6.6; PM: −19.7, 95%CI −32.2 to −7.2; PaDi: −1.5 points on NRS, 95%CI −2.5 to −0.4; all P < 0.05) and higher quality of life than WL (SF-36, Physical Functioning: 7.5, 95%CI 1.4 to 13.5; Bodily Pain: 14.9, 95%CI 4.4 to 25.4; Physical Component Score: 5.0, 95%CI 1.4 to 8.5; all P < 0.05). No significant effect was found for NDI, MDT, or VDT, but TG showed significantly higher PPT at pain-areas than WL (in lg(kPa); pain-maximum: 0.088, 95%CI 0.029 to 0.148, pain-adjacent: 0.118, 95%CI 0.038 to 0.199; both P < 0.01). Conclusion. A single application of traditional cupping might be an effective treatment for improving pain, quality of life, and hyperalgesia in CNP