29 research outputs found
QED: Chiral transition and the issue of triviality
I give a review and progress report on studies of lattice QED. I emphasize
analytical results and methods that are applied in data analysis. Also, I
derive some bounds for the critical exponents and establish their connection
with scaling violations. Triviality, as realized in theory, is ruled
out on theoretical grounds. I show that the present data, if analyzed
correctly, all lead to the same conclusions. They are compatible with power law
scaling with nongaussian exponents.Comment: 6 pages, 7 figures (not included), ILL-(TH)-93-2
CHILDREN ATTITUDES TOWARD VARIOUS FORMS OF RESISTANCE TRAINING
Despite the belief that resistance training was dangerous or ineffective for children, the safety and effectiveness of such programs are now well documented. The goal of this study was to examine the attitudes of children toward different forms of resistance training in which they were involved. One hundred 3rd and 4th grade children served as participants (age 9.5 years). Before filling out a questionnaire, the students were involved in five different resistance exercises types: exercises with their own body weight, exercises with barbells 1 kg in weight each, exercises with elastic bands, exercises with a partner and exercises with a BOSU ball (under unstable conditions). The questionnaire with a Likert scale of 5 degrees with responses ranging from 1 (strongly agree) to 5 (strongly disagree) consisted of questions exploring attitudes and degree of motivation toward various modalities of resistance training and their use in physical education classes. All of the selected modalities were evaluated positively by the children. Over 50% of the children stated that they strongly like all of the selected resistance training modalities. Exercises on a BOSU ball were the children’s first choice (51%) followed by rubber bands (15%) while exercise with body weights were their last choice (9%). Within the limitations of the study, the data show that various modalities of resistance training exercises have the potential to increase physical activity and establish healthy physical activity patterns. The desire to experience new and different activities provided a significant role towards choice of modality of resistance training
Compositeness, Triviality and Bounds on Critical Exponents for Fermions and Magnets
We argue that theories with fundamental fermions which undergo chiral
symmetry breaking have several universal features which are qualitatively
different than those of theories with fundamental scalars. Several bounds on
the critical indices and follow. We observe that in four
dimensions the logarithmic scaling violations enter into the Equation of State
of scalar theories, such as , and fermionic models, such as
Nambu-Jona-Lasinio, in qualitatively different ways. These observations lead to
useful approaches for analyzing lattice simulations of a wide class of model
field theories. Our results imply that {\it cannot} be a good
guide to understanding the possible triviality of spinor .Comment: 12 pages, 3 figures (not included), ILL-(TH)-93-2
Universal Properties of Chiral Simmetry Breaking
We discuss chiral symmetry breaking critical points from the perspective of
PCAC, correlation length scaling and the chiral equation of state. A scaling
theory for the ratio of the pion to sigma masses is presented. The
Goldstone character of the pion and properties of the longitudinal and
transverse chiral susceptibilities determine the ratio which can be
used to locate critical points and measure critical indices such as .
We show how PCAC and correlation length scaling determine the pion mass'
dependence on the chiral condensate and lead to a practical method to measure
the anomalous dimension . These tools are proving useful in studies of
the chiral transition in lattice QED and the quark-gluon plasma transition in
lattice QCD.Comment: 19 pages, 4 figures. CERN-TH.6630/92 ILL-(TH)-92-1
DIFFERENCES IN EXPLOSIVE STRENGTH OF LEGS BETWEEN FOOTBALL AND FUTSAL PLAYERS
Football and futsal belong to the group of polystructural activities of a complex character. From the motor aspect, both games are defined by a complex structure, comprised of various movements of the cyclic and acyclic type. Football and futsal are characterized by specific movements of the lower limbs, which are used to regulate possession of the ball (leading, passing) as well as the movement of the torso and hitting the ball with the head. The movement structure is comprised of various activities: running, jumping, turning, reception and shooting the ball. The aim of this research is to establish whether there are statistically significant differences in the explosive strength of the legs in football and futsal players. The analysis involved a sample of 37 participants, divided into two subsamples, the first being senior football players (first lineup) of FC "Radnički" from Niš – 23, and the second being senior futsal players (first lineup) of Futsal Club "Kopernikus" from Niš – 14 participants. The explosive strength of the lower limbs was estimated through the following tests: Squat Jump (SJ), Counter Movement Jump without arms swing (CMJ) and Counter Movement Jump with arms swing (CMJS). The Multivariate Analysis of Variance method(МАNOVA) was used to determine the differences between the groups, while the Analysis of Variance method (ANOVA) was used for the differences between the groups in terms of separate measuringt instruments. It has been determined that there are differences in the explosive strength of the legs between football players and futsal players
Multistep generalized transformation method applied to solving equations of discrete and continuous time-fractional enzyme kinetics
In this paper, Caputo based Michaelis–Menten kinetic model based on Time Scale Calculus (TSC) is proposed. The main reason for its consideration is a study of tumor cells population growth dynamics. In the particular case discrete-continuous time kinetics, Michaelis–Menten model is numerically treated, using a new algorithm proposed by authors, called multistep generalized difference transformation method (MSGDETM). In addition numerical simulations are performed and is shown that it represents the upgrade of the multi-step variant of generalized differential transformation method (MSGDTM). A possible conditions for its further development are discussed and possible experimental verification is described.This is the peer-reviewed version of the article: Vosika, Z., Mitić, V.V., Vasić, A., Lazović, G., Matija, L., Kocić, L.M., 2017. Multistep generalized transformation method applied to solving equations of discrete and continuous time-fractional enzyme kinetics. Communications in Nonlinear Science and Numerical Simulation 44, 373–389. [https://doi.org/10.1016/j.cnsns.2016.08.024
Looking for the Logarithms in Four-Dimensional Nambu-Jona-Lasinio Models
We study the problem of triviality in the four dimensional Nambu-Jona-Lasinio
model with discrete chiral symmetry using both large-N expansions and lattice
simulations. We find that logarithmic corrections to scaling appear in the
equation of state as predicted by the large-N expansion. The data from
lattice simulations is sufficiently accurate to distinguish logarithmically
trivial scaling from power law scaling. Simulations on different lattice sizes
reveal an interesting interplay of finite size effects and triviality. We argue
that such effects are qualitatively different for theories based on fundamental
scalar rather than fermion fields. Several lessons learned here can be applied
to simulations and analyses of more challenging field theories.Comment: 25 pages, 14 ps figure
Supplementary data for article: Veselinović, J. B.; Kocić, G. M.; Pavic, A.; Nikodinovic-Runic, J.; Senerovic, L.; Nikolić, G. M.; Veselinović, A. M. Selected 4-Phenyl Hydroxycoumarins: In Vitro Cytotoxicity, Teratogenic Effect on Zebrafish (Danio Rerio) Embryos and Molecular Docking Study. Chemico-Biological Interactions 2015, 231, 167–174. https://doi.org/10.1016/j.cbi.2015.02.011
Supplementary material for: [https://doi.org/10.1016/j.cbi.2015.02.011]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1699
Phenomenological interaction between current quarks
We construct a phenomenological model which describes the dynamical chiral
symmetry breaking (DCSB) of QCD vacuum and reproduces meson spectra. Quark
condensates, the pion decay constant, and meson spectra are well reproduced by
phenomenological interaction which consists of a linear confining potential, a
Coulombic potential, and the 't Hooft determinant interaction. In this model,
the 't Hooft determinant interaction plays a important role not to only
\eta,\eta' mass difference, but other meson masses through DCSB.Comment: 18 pages, LaTe
Phase Transitions at Finite Temperature and Dimensional Reduction for Fermions and Bosons
In a recent Letter we discussed the fact that large- expansions and
computer simulations indicate that the universality class of the finite
temperature chiral symmetry restoration transition in the 3D Gross-Neveu model
is mean field theory. This was seen to be a counterexample to the standard
'sigma model' scenario which predicts the 2D Ising model universality class. In
this article we present more evidence, both theoretical and numerical, that
this result is correct. We develop a physical picture for our results and
discuss the width of the scaling region (Ginzburg criterion),
corrections, and differences between the dynamics of BCS superconductors and
Gross-Neveu models. Lattices as large as are simulated for
both the and cases and the numerical evidence for mean field
scaling is quite compelling. We point out that the amplitude ratio for the
model's susceptibility is a particulartly good observable for distinguishing
between the dimensional reduction and the mean field scenerios, because this
universal quantity differs by almost a factor of in the two cases. The
simulations are done close to the critical point in both the symmetric and
broken phases, and correlation lengths of order are measured. The critical
indices and also pick out mean field behavior. We trace
the breakdown of the standard scenario (dimensional reduction and universality)
to the composite character of the mesons in the model. We point out that our
results should be generic for theories with dynamical symmetry breaking, such
as Quantum Chromodynamics.
We also simulated the model on lattices to establish
that our methods give the results of dimensional reduction in purely bosonicComment: 47 pages, latex, 23 figures in one uuencoded fil