778 research outputs found
Overbite as an Etiological Factor of TMJ Disorders. Clinical and Electromyographic Exploration
INTRODUCTION: The intermaxillar relationship in overbite is one of the etiological factors of TMJ disorders (Pulinger, Sellingman and Gorbeirn, 1993). Nevertheless, it does not always cause malfunction. Sometimes the compensating mechanisms of the individual prevent the occurrence of symptoms and it only appears when parafunctional habit overloads the stomatognathic apparatus.
OBJECTIVE: The aim of this study was to escamine neuromuscular behaviour in patients with such occlusal alteration.
MATERIAL AND METHODS: We present two cases with overbite: one bruxist with malfunction and one nonbruxist without symptoms of malfunction. An occlusal analysis and clinical, kinesiographic and
electromyographic exploration was performed in both patients. For the analysis we used a Dentatus A.R.L. articulator,
Myotronics electromyograph and K6 kinesiograph.
RESULTS AND CONCLUSIONS: The results of the exploration were compared with those of a healthy individual with normal occlusion, used as a reference. Lateral movements were restricted and with a mainly vertical component. In both cases there was an increase in electromyographic activity during normal mastication and swallowing, and in maximum force bite there was the same response between
anterior temporalis and masseter muscles. The study demonstrated that the mandibular movements in both patients were very similar, and determined by the occlusal factor, in comparison to normal individuals. Nevertheless, the electromyographic exploration shows
a different neuromuscular response by the patient adapted to this occlusal problem and the dysfunctional patient
U Geminorum: a test case for orbital parameters determination
High-resolution spectroscopy of U Gem was obtained during quiescence. We did
not find a hot spot or gas stream around the outer boundaries of the accretion
disk. Instead, we detected a strong narrow emission near the location of the
secondary star. We measured the radial velocity curve from the wings of the
double-peaked H emission line, and obtained a semi-amplitude value that
is in excellent agreement with the obtained from observations in the
ultraviolet spectral region by Sion et al. (1998). We present also a new method
to obtain K_2, which enhances the detection of absorption or emission features
arising in the late-type companion. Our results are compared with published
values derived from the near-infrared NaI line doublet. From a comparison of
the TiO band with those of late type M stars, we find that a best fit is
obtained for a M6V star, contributing 5 percent of the total light at that
spectral region. Assuming that the radial velocity semi-amplitudes reflect
accurately the motion of the binary components, then from our results: K_em =
107+/-2 km/s; K_abs = 310+/-5 km/s, and using the inclination angle given by
Zhang & Robinson(1987); i = 69.7+/-0.7, the system parameters become: M_WD =
1.20+/-0.05 M_sun,; M_RD = 0.42+/-0.04 M_sun; and a = 1.55+/- 0.02 R_sun. Based
on the separation of the double emission peaks, we calculate an outer disk
radius of R_out/a ~0.61, close to the distance of the inner Lagrangian point
L_1/a~0.63. Therefore we suggest that, at the time of observations, the
accretion disk was filling the Roche-Lobe of the primary, and that the matter
leaving the L_1 point was colliding with the disc directly, producing the hot
spot at this location.Comment: 36 pages, 14 figures, ccepted for publication in A
Agromining: farming metals for biosourced materials
Objectius de Desenvolupament Sostenible::12 - ProducciĂł i Consum Responsable
A Radio Polarimetric Study of the Galactic Center Threads
Multi-frequency, polarimetric VLA observations of the non-thermal filaments
(NTF's), G0.08+0.15, and G359.96+0.09, also known as the Northern and Southern
Threads are presented at 20, 6, 3.6 and 2 cm, with high enough spatial
resolution to be resolved for the first time at 6 and 3.6 cm. The 20 cm image
reveals a wealth of new detail in the radio sources lying within the inner 60
pc of the Galaxy. The Southern Thread has a prominent split along its length,
similar to splitting at the ends of previously studied NTF's. With resolutions
as fine as 2'', the 3.6 and 6 cm images reveal a high degree of continuity and
little substructure internal to the filament. The spectral index of the
Northern Thread has been determined over a broad range of frequencies. Its flux
density falls with frequency, alpha=-0.5 between 90 and 6 cm, and becomes much
steeper (alpha=-2.0) between 6 and 2 cm. The spectral index does not vary
significantly along the length of the Northern Thread, which implies either
that the diffusion timescale for the emitting electrons is less than their
synchrotron lifetime, or that the emitting electrons are reaccelerated
continuously at multiple positions along the filament. Because of the lack of
spectral index variation, we have not located the source of relativistic
electrons. Polarization observations at 6 and 3.6 cm confirm the non-thermal
nature of the emission from the Northern Thread. The fractional polarization in
the Northern Thread reaches 70% in some regions, although the polarized
emission is patchy. Large rotation measures (RM > 2000 rad/m2) have been
observed with irregular variations across the filament.The intrinsic magnetic
field in the Northern Thread is predominantly aligned along its long axis.Comment: 19 pages, incl. 24 figs; to appear in the Astrophysical Journa
Very Large Telescope Observations of the peculiar globular cluster NGC6712. Discovery of a UV, H-alpha excess star in the core
We present results from multi-band observations in the central region of the
cluster NGC6712 with the ESO-Very Large Telescope. Using high resolution images
we have identified three UV-excess stars. In particular two of them are within
the cluster core, a few arcsec apart: the first object is star "S" which
previous studies identified as the best candidate to the optical counterpart to
the luminous X-ray source detected in this cluster. The other UV object shows
clearcut H-alpha emission and, for this reason, is an additional promising
interacting binary candidate (a quiescent LMXB or a CV). The presence of two
unrelated interacting binary systems a few arcsec apart in the core of this
low-density cluster is somewhat surprising and supports the hypothesis that the
(internal) dynamical history of the cluster and/or the (external) interaction
with the Galaxy might play a fundamental role in the formation of these
peculiar objects.Comment: 15 pages, 3 figures. ApJL in pres
An International Validation of the âDECAF Scoreâ to Predict Disease Severity and Hospital Mortality in Acute Exacerbation of COPD in the UAE
Recycling versus Long-Term Storage of Nuclear Fuel: Economic Factors
The objective of the present study is to compare the associated costs of long-term storage of spent nuclear fuelâopen cycle strategyâwith the associated cost of reprocessing and recycling strategy of spent fuelâclosed cycle strategyâbased on the current international studies. The analysis presents cost trends for both strategies. Also, to point out the fact that the total cost of spent nuclear fuel management (open cycle) is impossible to establish at present, while the related costs of the closed cycle are stable and known, averting uncertainties
Evidence of magnetic accretion in an SW Sex star: discovery of variable circular polarization in LS Pegasi
We report on the discovery of variable circular polarization in the SW Sex
star LS Pegasi. The observed modulation has an amplitude of ~0.3 % and a period
of 29.6 minutes, which we assume as the spin period of the magnetic white
dwarf. We also detected periodic flaring in the blue wing of Hbeta, with a
period of 33.5 minutes. The difference between both frequencies is just the
orbital frequency, so we relate the 33.5-min modulation to the beat between the
orbital and spin period. We propose a new accretion scenario in SW Sex stars,
based on the shock of the disk-overflown gas stream against the white dwarf's
magnetosphere, which extends to the corotation radius. From this geometry, we
estimate a magnetic field strength of B(1) ~ 5-15 MG. Our results indicate that
magnetic accretion plays an important role in SW Sex stars and we suggest that
these systems are probably Intermediate Polars with the highest mass accretion
rates.Comment: Accepted by ApJ Letters. LaTeX, 14 pages, 3 PostScript figure
Evaluation of the antioxidant activity in food model system of fish peptides released during simulated gastrointestinal digestion
Feasibility Studies for Single Transverse-Spin Asymmetry Measurements at a Fixed-Target Experiment Using the LHC Proton and Lead Beams (AFTER@LHC)
The measurement of Single Transverse-Spin Asymmetries, A_N, for various quarkonium states and DrellâYan lepton pairs can shed light on the orbital angular momentum of quarks and gluons, a fundamental ingredient of the proton-spin puzzle. The AFTER@LHC proposal combines a unique kinematic coverage and large luminosities thanks to the Large Hadron Collider beams to deliver precise measurements, complementary to the knowledge provided by collider experiments such as at RHIC. In this paper, we report on sensitivity studies for J/ Ï, ΄ and DrellâYan A_N done using the performance of LHCb-like or ALICE-like detectors, combined with polarised gaseous hydrogen and helium-3 targets. In particular, such analyses will provide us with new insights and knowledge about transverse-momentum-dependent parton distribution functions for quarks and gluons and on twist-3 collinear matrix elements in the proton and the neutron
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