1,445 research outputs found
Translesion synthesis DNA polymerase η exhibits a specific RNA extension activity and a transcription-associated function
We thank Andres Aguilera for providing the pCYC-LacZ plasmid for the GLRO experiments, and Szilvia Minorits for technical assistance. This work was also supported by grants from the National Research, Development and Innovation Office: GINOP-2.3.2-15-2016-00001 and GINOP-2.3.2-15-2016-00024.Peer reviewedPublisher PD
Tremor in motor neuron disease may be central rather than peripheral in origin
BACKGROUND AND PURPOSE:
Motor neuron disease (MND) refers to a spectrum of degenerative diseases affecting motor neurons. Recent clinical and post-mortem observations have revealed considerable variability in the phenotype. Rhythmic involuntary oscillations of the hands during action, resembling tremor, can occur in MND, but their pathophysiology has not yet been investigated.
METHODS:
A total of 120 consecutive patients with MND were screened for tremor. Twelve patients with action tremor and no other movement disorders were found. Ten took part in the study. Tremor was recorded bilaterally using surface electromyography (EMG) and triaxial accelerometer, with and without a variable weight load. Power spectra of rectified EMG and accelerometric signal were calculated. To investigate a possible cerebellar involvement, eyeblink classic conditioning was performed in five patients.
RESULTS:
Action tremor was present in about 10% of our population. All patients showed distal postural tremor of low amplitude and constant frequency, bilateral with a small degree of asymmetry. Two also showed simple kinetic tremor. A peak at the EMG and accelerometric recordings ranging from 4 to 12 Hz was found in all patients. Loading did not change peak frequency in either the electromyographic or accelerometric power spectra. Compared with healthy volunteers, patients had a smaller number of conditioned responses during eyeblink classic conditioning.
CONCLUSIONS:
Our data suggest that patients with MND can present with action tremor of a central origin, possibly due to a cerebellar dysfunction. This evidence supports the novel idea of MND as a multisystem neurodegenerative disease and that action tremor can be part of this condition
QCD thermodynamics with continuum extrapolated Wilson fermions II
We continue our investigation of 2+1 flavor QCD thermodynamics using
dynamical Wilson fermions in the fixed scale approach. Two additional pion
masses, approximately 440 MeV and 285 MeV, are added to our previous work at
545 MeV. The simulations were performed at 3 or 4 lattice spacings at each pion
mass. The renormalized chiral condensate, strange quark number susceptibility
and Polyakov loop is obtained as a function of the temperature and we observe a
decrease in the light chiral pseudo-critical temperature as the pion mass is
lowered while the pseudo-critical temperature associated with the strange quark
number susceptibility or the Polyakov loop is only mildly sensitive to the pion
mass. These findings are in agreement with previous continuum results obtained
in the staggered formulation.Comment: 19 pages, 13 figures, published versio
The mixing of two-pion and vector-meson states using staggered fermions
In this study we employ staggered fermions to calculate the two-pion taste
singlet states at rest. Leveraging the Clebsch-Gordan coefficients of the
symmetry group associated with staggered fermions, we effectively compute the
contributions to the resting -meson correlator. To discern the
distinct energy states involved, we adopt a generalized eigenvalue
problem-solving approach. This work will provide insight into the important
role played by the two-pion contribution to the anomalous magnetic moment of
the muon.
In this paper we present our group theoretic considerations and preliminary
results on the contribution of two-pion states to the rho meson correlation
function.Comment: 8 pages, 2 tables, 5 figure
Chiral damping of magnetic domain walls
Structural symmetry breaking in magnetic materials is responsible for a
variety of outstanding physical phenomena. Examples range from the existence of
multiferroics, to current induced spin orbit torques (SOT) and the formation of
topological magnetic structures. In this letter we bring into light a novel
effect of the structural inversion asymmetry (SIA): a chiral damping mechanism.
This phenomenon is evidenced by measuring the field driven domain wall (DW)
motion in perpendicularly magnetized asymmetric Pt/Co/Pt trilayers. The
difficulty in evidencing the chiral damping is that the ensuing DW dynamics
exhibit identical spatial symmetry to those expected from the
Dzyaloshinskii-Moriya interaction (DMI). Despite this fundamental resemblance,
the two scenarios are differentiated by their time reversal properties: while
DMI is a conservative effect that can be modeled by an effective field, the
chiral damping is purely dissipative and has no influence on the equilibrium
magnetic texture. When the DW motion is modulated by an in-plane magnetic
field, it reveals the structure of the internal fields experienced by the DWs,
allowing to distinguish the physical mechanism. The observation of the chiral
damping, not only enriches the spectrum of physical phenomena engendered by the
SIA, but since it can coexists with DMI it is essential for conceiving DW and
skyrmion devices
Charmonium spectral functions from 2+1 flavour lattice QCD
Finite temperature charmonium spectral functions in the pseudoscalar and
vector channels are studied in lattice QCD with 2+1 flavours of dynamical
Wilson quarks, on fine isotropic lattices (with a lattice spacing of 0.057 fm),
with a non-physical pion mass of 545 MeV. The highest
temperature studied is approximately . Up to this temperature no
significant variation of the spectral function is seen in the pseudoscalar
channel. The vector channel shows some temperature dependence, which seems to
be consistent with a temperature dependent low frequency peak related to heavy
quark transport, plus a temperature independent term at \omega>0. These results
are in accord with previous calculations using the quenched approximation.Comment: 17 pages, 9 figures, 2 table
Causal links between external contingencies of self-worth and mindfulness
Outcome research confirming the salutary effects of mindfulness-based interventions has proliferated in the last fifteen years. In contrast, there has been very little research into intra-individual factors that may enhance or inhibit mindfulness. The present study examined a proposal by Brown, Ryan and Creswell (2007a) that external contingent self-worth may act as an inhibiting factor of mindfulness. Undergraduate participants performed two reading tasks; one under neutral conditions and one under the influence of an academic ego-threat. Momentary mindfulness levels were measured retrospectively following both reading tasks. It was expected that levels of academic competence contingent self-worth would predict changes in momentary mindfulness levels between the ego-threat and neutral condition, and, in addition, that worry would mediate the relationship. The study findings supported both hypotheses. The theoretical implications of the study are discussed in relation to the salience of self-investment in present moment events as a controlling variable of levels of momentary mindfulness
- …