1,574 research outputs found
Interplay between Heavy Fermions and Crystal Field Excitation in Kondo Lattices. Low-Temperature Thermodynamics and Inelastic Neutron Scattering Spectra of CeNiSn
The microscopic theory of interaction between the heavy fermions and the
crystal field excitations in Kondo lattices is presented. It is shown that the
heavy-fermion spectrum scaled by the Kondo temperature can be modified by
the crystal field excitations with the energy provided the
inequality is realized. On the base of general description of
excitation spectrum the detailed qualitative and quantitative explanation of
anisotropic inelastic neutron scattering spectra and low-temperature specific
heat of orthorhombic CeNiSn is given. The theory resolves the apparent
contradiction between the metallic conductivity and the gap-wise behavior of
thermodynamic properties and spin response of CeNiSn at low temperatures.Comment: 24 pages (LaTeX), 12 Postscript figures, submitted to Phys.Rev.
Characterizing Scales of Genetic Recombination and Antibiotic Resistance in Pathogenic Bacteria Using Topological Data Analysis
Pathogenic bacteria present a large disease burden on human health. Control
of these pathogens is hampered by rampant lateral gene transfer, whereby
pathogenic strains may acquire genes conferring resistance to common
antibiotics. Here we introduce tools from topological data analysis to
characterize the frequency and scale of lateral gene transfer in bacteria,
focusing on a set of pathogens of significant public health relevance. As a
case study, we examine the spread of antibiotic resistance in Staphylococcus
aureus. Finally, we consider the possible role of the human microbiome as a
reservoir for antibiotic resistance genes.Comment: 12 pages, 6 figures. To appear in AMT 2014 Special Session on
Advanced Methods of Interactive Data Mining for Personalized Medicin
Cigarette Smoking, Birthweight and Osteoporosis in Adulthood: Results from the Hertfordshire Cohort Study
We looked for interaction between early environment and adult lifestyle in determination of bone mineral content (BMC) and bone mineral density (BMD) among 498 men and 468 women for whom birth records were available. Participants completed a health questionnaire, and bone densitometry (DXA) of the lumbar spine and femoral neck performed
Disordered Hubbard Model with Attraction: Coupling Energy of Cooper Pairs in Small Clusters
We generalize the Cooper problem to the case of many interacting particles in
the vicinity of the Fermi level in the presence of disorder. On the basis of
this approach we study numerically the variation of the pair coupling energy in
small clusters as a function of disorder. We show that the Cooper pair energy
is strongly enhanced by disorder, which at the same time leads to the
localization of pairs.Comment: revtex, 5 pages, 6 figure
Strange particle production at RHIC in a single-freeze-out model
Strange particle ratios and pT-spectra are calculated in a thermal model with
single freeze-out, previously used successfully to describe non-strange
particle production at RHIC. The model and the recently released data for phi,
Lambda, anti-Lambda, and K*(892) are in very satisfactory agreement, showing
that the thermal approach can be used to describe the strangeness production at
RHIC.Comment: We have added the comparison of the model predictions to the newly
released Lambda and K*(892) pT-spectra from STA
Effects of a single aerobic exercise session on body image
Background and Objectives
Most research on the effects of exercise on body image has concentrated on the benefits of regular exercise. However, some research has indicated that exercise has an immediate impact on body image. The aims of this study were to investigate the immediate effects of aerobic exercise in a fitness class and the at-home environment on body image, and to examine the impact of nutritional status (i.e., normal weight vs. overweight/obesity) and exercise addiction on these changes.
Method
322 Hungarian women participated in the study with two different environmental conditions, fitness class condition (N = 155) and at-home video condition (N = 167). They completed the Body Appreciation Scale and Exercise Addiction Inventory before and after a one-hour aerobic exercise session. Self-report data on weight, height and exercise frequency were also collected.
Results
There were no significant differences between the fitness class and video groups in terms of age, educational level, BMI, body appreciation, exercise frequency and exercise addiction. We found that 7.5% (N = 24) of the participants were at risk for exercise addiction. Aerobic exercise had a significant positive effect on body appreciation (t(321) = 7.564, p < .001) independently from environment and nutritional status. Exercise addiction moderated the relationship between exercise and body image, the at risk for exercise addiction group showed the greatest improvement (F(1) = 3.252, p = .040).
Conclusion
The results indicate that even a one-hour aerobic exercise session has a positive effect on body image; this has important practical implications for intervention strategies and weight-loss treatments.
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Elméleti háttér és célkitűzés
Bár a legtöbb kutatás a rendszeres testedzés testképre gyakorolt pozitív hatására fókuszál, néhány vizsgálat eredménye a testedzés testképre tett azonnali hatására hívja fel a figyelmet. Jelen tanulmány célja az aerobik edzés testképre gyakorolt azonnali hatásának vizsgálata fitnesztermi és otthoni edzési körülmények között, továbbá a tápláltsági állapot (normális testsúly vs. túlsúly/elhízás) és a testedzésfüggőség potenciális moderátor szerepének vizsgálata az edzés és a testkép alakulása közötti kapcsolatban.
Módszer
A vizsgálatba aerobikedzést folytató nőket vontunk be (n = 322). A résztvevők egyik része edzőteremben folytatta a testgyakorlást (n = 155), másik része otthon végzett aerobik testedzést, video vagy DVD segítségével (n = 167).
Mérőeszközök
önbeszámolóval nyert testtömeg és testmagasság, a testedzés gyakoriságára vonatkozó kérdés, Testértékelési Skála, Testedzés Addikció Kérdőív. Az adatfelvétel az egyórás testgyakorlást megelőzően és azt követően történt.
Eredmények
Nem találtunk szignifikáns különbséget az edzőteremben és az otthonukban aerobik edzést folytató nők között az életkor, az iskolai végzettség, a BMI, a testértékelés, a testedzés gyakorisága és a testedzésfüggőség tekintetében. A válaszadók 7,5%-a (n = 24) esetében jelenik meg a testedzésfüggőség kockázata. Az egyórás testedzés szignifikáns, kedvező hatást gyakorolt a testképre (t(321) = 7,564; p < 0,001), amely hatás a testgyakorlás helyszínétől (edzőterem vs. otthon) és a tápláltsági állapottól függetlennek bizonyult. A testedzésfüggőség azonban moderálta a testgyakorlás és a testkép változásának kapcsolatát: a testedzést követően a testedzésfüggőség szempontjából veszélyeztetett csoportban mutatkozott meg a legnagyobb mértékű, pozitív irányú változás a testkép tekintetében (F(1) = 3,252; p = 0,040).
Következtetés
Eredményeink arra utalnak, hogy akár egy egyórás testgyakorlásnak is pozitív hatása lehet a testképre, amelynek jelentős gyakorlati implikációi vannak a testsúlycsökkentő kezelések szempontjából
Hydrodynamical analysis of hadronic spectra in the 130 GeV/nucleon Au+Au collisions
We study one-particle spectra and a two-particle correlation function in the
130 GeV/nucleon Au+Au collisions at RHIC by making use of a hydrodynamical
model. We calculate the one-particle hadronic spectra and present the first
analysis of Bose-Einstein correlation functions based on the numerical solution
of the hydrodynamical equations which takes both longitudinal and transverse
expansion into account appropriately. The hydrodynamical model provides
excellent agreement with the experimental data in the pseudorapidity and the
transverse momentum spectra of charged hadrons, the rapidity dependence of
anti-proton to proton ratio, and almost consistent result for the pion
Bose-Einstein correlation functions. Our numerical solution with simple
freeze-out picture suggests the formation of the quark-gluon plasma with large
volume and low net-baryon density.Comment: 7 pages, 8 figures, REVTeX4. Numerical results and figures are
correcte
Adaptation of Left Ventricular Twist Mechanics in Exercise-Trained Children Is Only Evident after the Adolescent Growth Spurt.
The extent of structural cardiac remodeling in response to endurance training is maturity dependent. In adults, this structural adaptation is often associated with the adaptation of left ventricular (LV) twist mechanics. For example, an increase in LV twist often follows an expansion in end-diastolic volume, whereas a reduction in twist may follow a thickening of the LV walls. While structural cardiac remodeling has been shown to be more prominent post-peak height velocity (PHV), it remains to be determined how this maturation-dependent structural remodeling influences LV twist. Therefore, we aimed to (1) compare LV twist mechanics between trained and untrained children pre- and post-PHV and (2) investigate how LV structural variables relate to LV twist mechanics pre- and post-PHV.
Left ventricular function and morphology were assessed (echocardiography) in endurance-trained and untrained boys (n = 38 and n = 28, respectively) and girls (n = 39 and n = 34, respectively). Participants were categorized as either pre- or post-PHV using maturity offset to estimate somatic maturation.
Pre-PHV, there were no differences in LV twist or torsion between trained and untrained boys (twist: P = .630; torsion: P = .382) or girls (twist: P = .502; torsion: P = .316), and LV twist mechanics were not related with any LV structural variables (P > .05). Post-PHV, LV twist was lower in trained versus untrained boys (P = .004), with torsion lower in trained groups, irrespective of sex (boys: P < .001; girls: P = .017). Moreover, LV torsion was inversely related to LV mass (boys: r = -0.55, P = .001; girls: r = -0.46, P = .003) and end-diastolic volume (boys: r = -0.64, P < .001; girls: r = -0.36, P = .025) in both sexes.
A difference in LV twist mechanics between endurance-trained and untrained cohorts is only apparent post-PHV, where structural and functional remodeling were related
Particlization in hybrid models
In hybrid models, which combine hydrodynamical and transport approaches to
describe different stages of heavy-ion collisions, conversion of fluid to
individual particles, particlization, is a non-trivial technical problem. We
describe in detail how to find the particlization hypersurface in a 3+1
dimensional model, and how to sample the particle distributions evaluated using
the Cooper-Frye procedure to create an ensemble of particles as an initial
state for the transport stage. We also discuss the role and magnitude of the
negative contributions in the Cooper-Frye procedure.Comment: 18 pages, 28 figures, EPJA: Topical issue on "Relativistic Hydro- and
Thermodynamics"; version accepted for publication, typos and error in Eq.(1)
corrected, the purpose of sampling and change from UrQMD to fluid clarified,
added discussion why attempts to cancel negative contributions of Cooper-Frye
are not applicable her
Hadronic freeze-out following a first order hadronization phase transition in ultrarelativistic heavy-ion collisions
We analyze the hadronic freeze-out in ultra-relativistic heavy ion collisions
at RHIC in a transport approach which combines hydrodynamics for the early,
dense, deconfined stage of the reaction with a microscopic non-equilibrium
model for the later hadronic stage at which the hydrodynamic equilibrium
assumptions are not valid. With this ansatz we are able to self-consistently
calculate the freeze-out of the system and determine space-time hypersurfaces
for individual hadron species. The space-time domains of the freeze-out for
several hadron species are found to be actually four-dimensional, and differ
drastically for the individual hadrons species. Freeze-out radii distributions
are similar in width for most hadron species, even though the Omega-baryon is
found to be emitted rather close to the phase boundary and shows the smallest
freeze-out radii and times among all baryon species. The total lifetime of the
system does not change by more than 10% when going from SPS to RHIC energies.Comment: 11 pages, 4 eps-figures included, revised versio
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