8,043 research outputs found
Características Antropométricas en Atletas de Jiu Jitsu Brasilero de Alto Nivel: Rol del Estilo de Lucha
Indexación: Web of Science; Scielo.SUMMARY: Human performance efficiency and effectiveness in different sports depend to a large extent on the size, weight and proportion of the physique of the athlete. The aim of this study was to identify morphological characteristics of Brazilian Jiu-Jitsu (BJJ) athletes. The sample consisted of 25 highly trained male athletes who were classified according to their fighting style; guard fighter (GF) vs. pass fighter (PF). The athletes were assessed for somatotype, body composition and proportionality. For the whole group of athletes the somatotype was 2.23±0.68, 6.33±1.14, and 1.75±0.87 for endomorph, mesomorph and ectomorph components, respectively. Muscle and adipose tissue percentages were 52.34±2.15% and 19.30±2.51%, respectively. PF were significantly more mesomorph (p< 0.05) and less ectomorph (p< 0.05) than GF. Also, PF had significantly higher phantom Z score for bone mass vs. GF (0.51±0.57 vs. 0.01±0.54; p<0.05), and significantly lower muscle mass- bone mass ratio (4.55±0.31 vs. 4.77±0.56; p<0.05), height (1.71±0.06 vs. 1.77±0.07; p<0.05) and height weight ratio (40.58±1.11 vs. 41.84±1.22). Our results show that morphological characteristics are related to different fighting styles in BJJ athletes.RESUMEN: La eficiencia y efectividad del rendimiento humano en diferentes deportes depende en gran medida del tamaño, peso y proporción del físico del atleta. El objetivo de este estudio fue identificar las características morfológicas de atletas jiu-jitsu brasileros. La muestra consintió de 25 atletas varones altamente entrenados, quienes fueron clasificados de acuerdo a su estilo de lucha; guarderos (GF) vs pasadores (PF). Se evaluó en los atletas somatotipo, composición corporal y proporcionalidad. Para el grupo total de atletas el somatotipo fue 2,23±0,68, 6,33±1,14 y 1,75±0,78 para el endomorfismo, mesomorfismo y ectomorfismo, respectivamente. Los porcentajes de tejido muscular y adiposo fueron 52,34±2,15% and 19,30±2,51%, respectivamente. PF fueron significativamente las mesomorfos (p<0,05) y menos ectomorfos (p<0,05) que GF. Además PF tuvieron una significativamente alto Z score para la masa ósea (4,55±0,31 vs. 4,77±0,56; p<0,05), estatura (1,71±0,06 vs. 1,77±0,07; p<0,05) y relación altura peso (40,58±1.11 vs. 41,84±1.22). Nuestros resultados muestran que las características morfológicas están relacionadas a diferentes estilos de lucha en atletas de BJJ.http://ref.scielo.org/bzhxy
Searching for galactic sources in the Swift GRB catalog
Since the early 1990s Gamma Ray Bursts have been accepted to be of
extra-galactic origin due to the isotropic distribution observed by BATSE and
the redshifts observed via absorption line spectroscopy. Nevertheless, upon
further examination at least one case turned out to be of galactic origin. This
particular event presented a Fast Rise, Exponential Decay (FRED) structure
which leads us to believe that other FRED sources might also be Galactic. This
study was set out to estimate the most probable degree of contamination by
galactic sources that certain samples of FREDs have. In order to quantify the
degree of anisotropy the average dipolar and quadripolar moments of each sample
of GRBs with respect to the galactic plane were calculated. This was then
compared to the probability distribution of simulated samples comprised of a
combination of isotropically generated sources and galactic sources. We observe
that the dipolar and quadripolar moments of the selected subsamples of FREDs
are found more than two standard deviations outside those of random
isotropically generated samples.The most probable degree of contamination by
galactic sources for the FRED GRBs of the Swift catalog detected until February
2011 that do not have a known redshift is about 21 out of 77 sources which is
roughly equal to 27%. Furthermore we observe, that by removing from this sample
those bursts that may have any type of indirect redshift indicator and multiple
peaks gives the most probable contamination increases up to 34% (17 out of 49
sources). It is probable that a high degree of contamination by galactic
sources occurs among the single peak FREDs observed by Swift.Comment: Published to A&A, 4 pages, 5 figures, this arXiv version includes
appended table with all the bursts considered in this stud
Genetic study in patients operated dentally and anesthetized with articaine-epinephrine
Aims: In this study we wanted to figure out if there was a correlation between OPRM1 N40D, TRPV1 I316M, TRPV1 I585V, NOS3 −786T>C and IL6 −174C>G polymorphisms and the response to locally applied articaine-epinephrine anesthetic.
Methods: In this observational study, 114 oral cell samples of patients anesthetized with articaine-epinephrine (54 from men 60 from women), were collected from dental centers in Madrid (Spain). High molecular weight DNA was obtained from oral mucosa cells. The analysis of OPRM1 N40D (rs1799971), TRPV1 I316M (rs222747), TRPV1 I585V (rs8065080) and IL6 −174C>G polymorphism was performed through real-time PCR allelic discrimination using TaqMan probes. Polymorphism NOS3 −786T> C (rs2070744) was analyzed using RFLP-PCR.
Results: The studied polymorphisms are involved neither in the response to the anesthetic, nor in the intensity of perceived dental pain. However, in a subset of female patients we found that TRPV1 I316M was associated with a delayed onset of anesthesia.
Conclusions: There is no association among these polymorphisms and the time elapsed between the application of the anesthetic and the onset of its effect
Kinetic energy of protons in ice Ih and water: a path integral study
The kinetic energy of H and O nuclei has been studied by path integral
molecular dynamics simulations of ice Ih and water at ambient pressure. The
simulations were performed by using the q-TIP4P/F model, a point charge
empirical potential that includes molecular flexibility and anharmonicity in
the OH stretch of the water molecule. Ice Ih was studied in a temperature range
between 210-290 K, and water between 230-320 K. Simulations of an isolated
water molecule were performed in the range 210-320 K to estimate the
contribution of the intramolecular vibrational modes to the kinetic energy. Our
results for the proton kinetic energy, K_H, in water and ice Ih show both
agreement and discrepancies with different published data based on deep
inelastic neutron scattering experiments. Agreement is found for water at the
experimental melting point and in the range 290-300 K. Discrepancies arise
because data derived from the scattering experiments predict in water two
maxima of K_H around 270 K and 277 K, and that K_H is lower in ice than in
water at 269 K. As a check of the validity of the employed water potential, we
show that our simulations are consistent with other experimental thermodynamic
properties related to K_H, as the temperature dependence of the liquid density,
the heat capacity of water and ice at constant pressure, and the isotopic shift
in the melting temperature of ice upon isotopic substitution of either H or O
atoms. Moreover, the temperature dependence of K_H predicted by the q-TIP4P/F
model for ice Ih is found to be in good agreement to results of path integral
simulations using ab initio density functional theory.Comment: 11 pages, 6 figures, 2 table
Optical Emission Model for Binary Black Hole Merger Remnants Travelling through Discs of Active Galactic Nucleus
Active galactic nuclei (AGNs) have been proposed as plausible sites hosting a
sizable fraction of the binary black hole (BBH) mergers measured through
gravitational waves (GWs) by the LIGO-Virgo-Kagra (LVK) experiment. These GWs
could be accompanied by radiation feedback due to the interaction of the BBH
merger remnant with the AGN disc. We present a new predicted radiation
signature driven by the passage of a kicked BBH remnant throughout a thin AGN
disc. We analyse the situation of a merger occurring outside the thin disc,
where the merger is of second or higher generation in a merging hierarchical
sequence. The coalescence produces a kicked BH remnant that eventually plunges
into the disc, accretes material, and inflates jet cocoons. We consider the
case of a jet cocoon propagating quasi-parallel to the disc plane and study the
outflow that results when the cocoon emerges from the disc. Here we focus on
the long time-scale emission produced after the disc outflow expands and
becomes optically thin. The bolometric luminosity of such disc outflow evolves
as . Depending on the parameter configuration, the flare
produced by the disc outflow could be comparable to or exceed the AGN
background emission at near-infrared, optical, and extreme ultraviolet
wavelengths appearing [20-500] days after the GW event and lasting for
[1-200] days, accordingly.Comment: 11 pages, 8 figures. Submitted to MNRA
A not so massive cluster hosting a very massive star
We present the first physical characterization of the young open cluster VVV
CL041. We spectroscopically observed the cluster main-sequence stellar
population and a very-massive star candidate: WR62-2. CMFGEN modeling to our
near-infrared spectra indicates that WR62-2 is a very luminous (10) and massive () star.Comment: 1 page, 1 figure, to be published in the "International Workshop on
Wolf-Rayet Stars conference proceedings" by Universit\"atsverlag Potsdam
(editors: W.-R. Hamann, A. Sander, and H. Todt
Somatotype Profile of Professional Male Soccer Chilean Players
Indexación: Web of Science; ScieloRESUMEN: El presente estudio pretende describir el somatotipo del futbolista profesional chileno, así como determinar la variabilidad existente en el somatotipo por posición de juego. Cien jugadores profesionales varones (edad 23±4,4 años), participantes del campeonato nacional de fútbol chileno fueron incluidos en el estudio. Se realizó la medición de 10 variables antropométricas según las normas de la International Society for the Advancement of Kinanthropometry (ISAK). Se calcularon los 3 componentes del somatotipo de Heath-Carter por cada posición de juego. El somatotipo grupal de la muestra estudiada presentó una clasificación de mesomorfobalanceado (2,25-5,32-2,26), siendo los defensas los con mayor predominio de este componente. La posición con menor dispersión en su somatotipo son defensas y arqueros, mientras que volantes y delanteros presentan mayor variabilidad. En conclusión, a pesar de existir un somatotipo en común, las diferencias en las varianzas entre posiciones de juego entregan información sobre la relevancia de la optimización morfológica en una posición específica de juego.
PALABRAS CLAVE: Somatotipo; Antropometría; Fútbol masculino.SUMMARY: The aim of this study was to describe the somatotype of Chilean professional soccer players, and to determine the variability in the somatotype by playing position. One hundred professional male players (age 23±4.4) participants in the Chilean national soccer championship were included in the study. We performed the measurement of 10 anthropometric variables according to the rules of the International Society for the Advancement of Kinanthropometry (ISAK). We calculated the 3 components of the Heath-Carter somatotype for each playing position. The somatotype of the sample group presents a balanced mesomorph classification (2.25-5.32-2.26),especially among defenders. The positions with less dispersion in their somatotype were the defenses and goalkeepers, while the flyers and forwards show more variability. In conclusion, although there is a common somatotype, differences in the variances between playing positions provide information about the relevance of morphological optimization in a playing position.
KEY WORDS: Anthropometry; Somatotype; Male soccer.http://ref.scielo.org/v4pdn
Solid helium at high pressure: A path-integral Monte Carlo simulation
Solid helium (3He and 4He) in the hcp and fcc phases has been studied by
path-integral Monte Carlo. Simulations were carried out in the
isothermal-isobaric (NPT) ensemble at pressures up to 52 GPa. This allows one
to study the temperature and pressure dependences of isotopic effects on the
crystal volume and vibrational energy in a wide parameter range. The obtained
equation of state at room temperature agrees with available experimental data.
The kinetic energy, E_k, of solid helium is found to be larger than the
vibrational potential energy, E_p. The ratio E_k/E_p amounts to about 1.4 at
low pressures, and decreases as the applied pressure is raised, converging to
1, as in a harmonic solid. Results of these simulations have been compared with
those yielded by previous path integral simulations in the NVT ensemble. The
validity range of earlier approximations is discussed.Comment: 7 pages, 5 figure
Noncommutative 6D Gauge Higgs Unification Models
The influence of higher dimensions in noncommutative field theories is
considered. For this purpose, we analyze the bosonic sector of a recently
proposed 6 dimensional SU(3) orbifold model for the electroweak interactions.
The corresponding noncommutative theory is constructed by means of the
Seiberg-Witten map in 6D. We find in the reduced bosonic interactions in 4D
theory, couplings which are new with respect to other known 4D noncommutative
formulations of the Standard Model using the Seiberg-Witten map.
Phenomenological implications due to the noncommutativity of extra dimensions
are explored. In particular, assuming that the commutative model leads to the
standard model values, a bound -5.63 10^{-8} GeV^{-2}< theta <1.06
10^{-7}GeV^{-2} on the corresponding noncommutativity scale is derived from
current experimental constraints on the S and T oblique parameters. This bound
is used to predict a possibly significant impact of noncommutativity effects of
extra dimensions on the rare Higgs boson decay H-> gamma gamma.Comment: Latex file, 11 pages, 1 figur
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