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1.
Phys Rev E ; 108(1-1): 014308, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37583232

RESUMEN

We discuss the majority vote model coupled with scale-free networks and investigate its critical behavior. Previous studies point to a nonuniversal behavior of the majority vote model, where the critical exponents depend on the connectivity. At the same time, the effective dimension D_{eff} is unity for a degree distribution exponent 5/2<γ<7/2. We introduce a finite-size theory of the majority vote model for uncorrelated networks and present generalized scaling relations with good agreement with Monte Carlo simulation results. Our finite-size approach has two sources of size dependence: an external field representing the influence of the mass media on consensus formation and the scale-free network cutoff. The critical exponents are nonuniversal, dependent on the degree distribution exponent, precisely when 5/2<γ<7/2. For γ≥7/2, the model is in the same universality class as the majority vote model on Erdos-Rényi random graphs. However, for γ=7/2, the critical behavior includes additional logarithmic corrections.

2.
Phys Rev E ; 105(3-1): 034105, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35428121

RESUMEN

We define a stochastic reaction-diffusion process that describes a consensus formation in a nonsedentary population. The process is a diffusive version of the majority-vote model, where the state update follows two stages: In the first stage, spins are allowed to jump to a random neighbor node with probabilities D_{+} and D_{-} for the respective spin orientations, and in the second stage, the spins in the same node can change its values according to the majority-vote update rule. The model presents a consensus formation phase when the concentration is greater than a threshold value and a paramagnetic phase on the converse for equal diffusion probabilities, i.e., maintaining the inversion symmetry. Setting unequal diffusion probabilities for the respective spin orientations is the same as applying an external magnetic field. The system undergoes a discontinuous phase transition for concentrations higher than the critical threshold on the external field. The individuals that diffuse more dominate the stationary collective opinion.

3.
Phys Rev Lett ; 127(6): 062003, 2021 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-34420329

RESUMEN

We describe an analysis comparing the pp[over ¯] elastic cross section as measured by the D0 Collaboration at a center-of-mass energy of 1.96 TeV to that in pp collisions as measured by the TOTEM Collaboration at 2.76, 7, 8, and 13 TeV using a model-independent approach. The TOTEM cross sections, extrapolated to a center-of-mass energy of sqrt[s]=1.96 TeV, are compared with the D0 measurement in the region of the diffractive minimum and the second maximum of the pp cross section. The two data sets disagree at the 3.4σ level and thus provide evidence for the t-channel exchange of a colorless, C-odd gluonic compound, also known as the odderon. We combine these results with a TOTEM analysis of the same C-odd exchange based on the total cross section and the ratio of the real to imaginary parts of the forward elastic strong interaction scattering amplitude in pp scattering for which the significance is between 3.4σ and 4.6σ. The combined significance is larger than 5σ and is interpreted as the first observation of the exchange of a colorless, C-odd gluonic compound.

4.
Int J Cosmet Sci ; 41(3): 265-273, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30982995

RESUMEN

OBJECTIVES: In view of the lack of studies about the morphological and structural changes caused by solar radiation in young people, the aim of the present study was to evaluate the photoageing-related changes in the skin of different age groups by biophysical and imaging techniques. METHODS: Forty-four healthy female subjects were divided into two age groups: Group 1 (G1): 18-35 years old and Group 2 (G2): 40-60 years old. The skin of malar region of the face was evaluated in terms of mechanical properties, disorder in the pigmentation pattern, morphological and structural changes using the Cutometer® , Colorimeter® , Visioface® and Dermascan C® devices and reflectance confocal microscopy (Vivascope® ). RESULTS: The results showed that the main changes in the skin of G1 were related to the pigmentation pattern, the papilla format and depletion of thin collagen fibres. These alterations were also observed in the skin of G2, but with more pronounced effects. CONCLUSION: The knowledge about the skin changes caused by photoageing obtained in this study is very important for the development of dermocosmetic products for more effective treatments particularly focused on this type of skin. Finally, objective characterization of photoageing showed the importance of photoprotective habits since the first years of life in order to retard the appearance of skin changes caused by solar radiation.


OBJECTIFS: Compte tenu du manque d'études sur les modifications structurelles et morphologiques causées par le rayonnement solaire chez les jeunes gens, le but de la présente étude était d'évaluer les changements liés au photovieillissement de la peau de différents groupes d'âges grâce des techniques de biophysique et d'imagerie. MÉTHODES: Quarante-quatre sujets féminins en bonne santé ont été divisés en deux groupes d'âges : Groupe 1 (G1) : 18-35 ans et Groupe 2 (G2) : 40-60 ans. La peau des régions malaires du visage a été évaluée en termes de propriétés mécaniques, troubles du schéma de pigmentation, et changements morphologiques et structurels à l'aide des dispositifs Cutometer®, Colorimeter®, Visioface® et Dermascan C® et de la microscopie confocale par réflectance (Vivascope®). RÉSULTATS: Les résultats ont montré que les principaux changements au niveau de la peau du G1 étaient liés au schéma de pigmentation, au format papillaire et à la déplétion de fines fibres de collagène. Ces altérations ont également été observées au niveau de la peau du G2, mais avec des effets plus prononcés. CONCLUSION: Les connaissances sur les modifications cutanées causées par le photovieillissement acquises grâce à cette étude sont très importantes pour le développement de produits dermo-cosmétiques pour des traitements plus efficaces axés plus particulièrement sur ce type de peau. Et enfin, la caractérisation objective du photovieillissement a montré l'importance des habitudes photoprotectrices depuis les premières années de vie afin de retarder l'apparition de modifications cutanées causées par le rayonnement solaire.


Asunto(s)
Envejecimiento de la Piel/efectos de la radiación , Luz Solar/efectos adversos , Rayos Ultravioleta/efectos adversos , Adolescente , Adulto , Fenómenos Biofísicos , Brasil , Elasticidad , Femenino , Humanos , Persona de Mediana Edad , Fenómenos Fisiológicos de la Piel , Pigmentación de la Piel , Viscosidad , Adulto Joven
5.
Appl Opt ; 57(27): 7910-7914, 2018 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-30462059

RESUMEN

Thermal conductivity of Er3+-doped yttrium aluminum perovskite has been obtained by the use of laser induced temperature distribution and time-independent heat propagation equations. By using the spatially resolved microluminescence technique, the fluorescence spectra on the sample surface were mapped during the laser focused heating process, and the local temperature was measured at different spots on the sample surface with micrometric resolution. Significant information about the temperature profile was obtained following the maximum temperature of the laser spot and the behavior of the heat diffusion on the surface of the irradiation side. These data were finally used to feed the heat propagation equations from where the thermal conductivity was evaluated.

6.
Phys Rev E ; 97(2-2): 029901, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29548199

RESUMEN

This corrects the article DOI: 10.1103/PhysRevE.93.042111.

7.
Phys Rev E ; 94(1-2): 019904, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27575239

RESUMEN

This corrects the article DOI: 10.1103/PhysRevE.93.042111.

8.
Phys Rev E ; 93(4): 042111, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-27176258

RESUMEN

We address the study of quasiperiodic interactions on a square lattice by using an Ising model with ferromagnetic and antiferromagnetic exchange interactions following a quasiperiodic Fibonacci sequence in both directions of a square lattice. We applied the Monte Carlo method, together with the Metropolis algorithm, to calculate the thermodynamic quantities of the system. We obtained the Edwards-Anderson order parameter q_{EA}, the magnetic susceptibility χ, and the specific heat c in order to characterize the universality class of the phase transition. We also use the finite size scaling method to obtain the critical temperature of the system and the critical exponents ß,γ, and ν. In the low-temperature limit we obtained a spin-glass phase with critical temperature around T_{c}≈2.274, and the critical exponents ß,γ, and ν, indicating that the quasiperiodic order induces a change in the universality class of the system. Also, we discovered a spin-glass ordering in a two-dimensional system which is rare and, as far as we know, the unique example is an under-frustrated Ising model.

9.
Physiol Res ; 63(5): 605-13, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24908082

RESUMEN

Several deleterious effects may occur when intense and exhaustive exercise (IE) is not well-planned. This study aimed to investigate the effects of a short duration IE on body chemical composition and hypothalamic-pituitary-adrenal (HPA) axis. C57Bl/6 mice were distributed into four groups (10 mice per group): control (C-4D and C-10D), 4 days (E-4D), and 10 days of IE (E-10D). IE program consisted of a daily running session at 85 % of maximum speed until the animal reached exhaustion. Body weight as well as total body water, fat and protein content were determined from animal carcasses. HPA activation was assessed by plasma corticosterone levels measured by radioimmunoassay and the weight of both the adrenal glands and thymus were measured. Plasma corticosterone levels increased by 64 % in both the E-4D and E-10D groups. The weight of the adrenal glands augmented by 74 % and 45 %, at 4 and 10 days of IE, respectively, whereas thymus weight diminished by 15 % only in the E-10D group. The total carcass fat content decreased by 20 % only at 4 days IE, whereas protein content decreased by 20 % in both E-4D and E-10D groups. A relationship between corticosterone plasma levels and loss of body protein content in both E-4D and E-10D groups was observed (R(2)=0.999). We concluded that IE may be related to HPA axis activation associated with remodeling of body chemical composition in C57BL/6 mice.


Asunto(s)
Composición Corporal , Sistema Hipotálamo-Hipofisario/metabolismo , Fatiga Muscular , Músculo Esquelético/metabolismo , Esfuerzo Físico , Sistema Hipófiso-Suprarrenal/metabolismo , Estrés Fisiológico , Glándulas Suprarrenales/anatomía & histología , Glándulas Suprarrenales/metabolismo , Animales , Biomarcadores/sangre , Corticosterona/sangre , Masculino , Ratones Endogámicos C57BL , Músculo Esquelético/anatomía & histología , Tamaño de los Órganos , Sistema Hipófiso-Suprarrenal/anatomía & histología , Proteínas/metabolismo , Proteolisis , Carrera , Timo/anatomía & histología , Factores de Tiempo
10.
Phys Rev Lett ; 108(18): 181803, 2012 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-22681058

RESUMEN

We study WW and WZ production with ℓνqq (ℓ=e,µ) final states using data collected by the D0 detector at the Fermilab Tevatron Collider corresponding to 4.3 fb(-1) of integrated luminosity from pp collisions at sqrt[s]=1.96 TeV. Assuming the ratio between the production cross sections σ(WW) and σ(WZ) as predicted by the standard model, we measure the total WV (V=W,Z) cross section to be σ(WV)=19.6(-3.0)(+3.2) pb and reject the background-only hypothesis at a level of 7.9 standard deviations. We also use b-jet discrimination to separate the WZ component from the dominant WW component. Simultaneously fitting WW and WZ contributions, we measure σ(WW)=15.9(-3.2)(+3.7) pb and σ(WZ)=3.3(-3.3)(+4.1) pb, which is consistent with the standard model predictions.

11.
Phys Rev Lett ; 108(12): 121802, 2012 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-22540571

RESUMEN

We report on a search for charged massive long-lived particles (CMLLPs), based on 5.2 fb(-1) of integrated luminosity collected with the D0 detector at the Fermilab Tevatron pp collider. We search for events in which one or more particles are reconstructed as muons but have speed and ionization energy loss (dE/dx) inconsistent with muons produced in beam collisions. CMLLPs are predicted in several theories of physics beyond the standard model. We exclude pair-produced long-lived gauginolike charginos below 267 GeV and Higgsino-like charginos below 217 GeV at 95% C.L., as well as long-lived scalar top quarks with mass below 285 GeV.

12.
Phys Rev Lett ; 108(3): 032004, 2012 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-22400731

RESUMEN

We present a measurement of the ratio of events with correlated t and t ̅t spins to the total number of t ̅t events. This ratio f is evaluated using a matrix-element-based approach in 729 t ̅t candidate events with a single lepton ℓ (electron or muon) and at least four jets. The analyzed p ̅p collisions data correspond to an integrated luminosity of 5.3 fb(-1) and were collected with the D0 detector at the Fermilab Tevatron collider operating at a center-of-mass energy √s=1.96 TeV. Combining this result with a recent measurement of f in dileptonic final states, we find f in agreement with the standard model. In addition, the combination provides evidence for the presence of spin correlation in t ̅t events with a significance of more than 3 standard deviations.

13.
Phys Rev Lett ; 108(2): 021801, 2012 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-22324670

RESUMEN

We present a search for pair production of doubly charged Higgs bosons in the processes qq¯â†’H(++)H(--) decaying through H(±±)→τ(±)τ(±),µ(±)τ(±),µ(±)µ(±). The search is performed in pp¯ collisions at a center-of-mass energy of √s = 1.96 TeV using an integrated luminosity of up to 7.0 fb(-1) collected by the D0 experiment at the Fermilab Tevatron Collider. The results are used to set 95% C.L. limits on the pair production cross section of doubly charged Higgs bosons and on their mass for different H(±±) branching fractions. Models predicting different H(±±) decays are investigated. Assuming B(H(±±)→τ(±)τ(±))=1 yields an observed (expected) lower limit on the mass of a left-handed H(L)(±±) boson of 128 (116) GeV and assuming B(H(±±)→µ(±)τ(±))=1 the corresponding limits are 144 (149) GeV. In a model with B(H(±±)→τ(±)τ(±))=B(H(±±)→µ(±)τ(±))=B(H(±±)→µ(±)µ(±))=1/3, we obtain M(H(L)(±±))>130 (138) GeV.

14.
São Paulo; Secretaria Municipal de Saúde de São Paulo; 2012. 4 p. ilus.
No convencional en Portugués | LILACS, Coleciona SUS, CRSSUL-Producao, Sec. Munic. Saúde SP, Sec. Munic. Saúde SP | ID: biblio-937348

RESUMEN

Em 2009 o município de São Paulo desencadeou ações inter setoriais com sociedade civil e comunidade para reduzir a vulnerabilidade social, denominada “Virada Social”. A Secretaria Municipal de Saúde (SMS) e a Coordenadoria Regional de Saúde Sul (CRS Sul) participaram da “Jornada da Saúde” propiciando o acesso aos serviços de promoção e prevenção da saúde: elaboração do cartão SUS, alimentação saudável, medidas de pressão arterial, glicemia, vacinas, prevenção de gravidez precoce e doenças sexualmente transmissíveis (DST) para adolescentes, prevenção de câncer do colo de útero, dengue, saúde bucal e outras


Asunto(s)
Humanos , Salud de la Familia , Servicios de Salud , Salud Mental , Salud Pública , Organización y Administración
15.
São Paulo; Secretaria Municipal de Saúde de São Paulo; 2012. 4 p. ilus.
No convencional en Portugués | LILACS, CAB-Producao, Sec. Munic. Saúde SP, CRSSUL-Producao, Sec. Munic. Saúde SP, Sec. Munic. Saúde SP | ID: lil-642638

RESUMEN

Em 2009 o município de São Paulo desencadeou ações inter setoriais com sociedade civil e comunidade para reduzir a vulnerabilidade social, denominada “Virada Social”. A Secretaria Municipal de Saúde (SMS) e a Coordenadoria Regional de Saúde Sul (CRS Sul) participaram da “Jornada da Saúde” propiciando o acesso aos serviços de promoção e prevenção da saúde: elaboração do cartão SUS, alimentação saudável, medidas de pressão arterial, glicemia, vacinas, prevenção de gravidez precoce e doenças sexualmente transmissíveis (DST) para adolescentes, prevenção de câncer do colo de útero, dengue, saúde bucal e outras.


Asunto(s)
Humanos , Salud de la Familia , Servicios de Salud , Salud Mental , Salud Pública , Organización y Administración
16.
São Paulo; SMS; 2012. 4 p. ilus.
No convencional en Portugués | Sec. Munic. Saúde SP, CRSSUL-Producao, Sec. Munic. Saúde SP, Sec. Munic. Saúde SP | ID: sms-2022

RESUMEN

Em 2009 o município de São Paulo desencadeou ações inter setoriais com sociedade civil e comunidade para reduzir a vulnerabilidade social, denominada “Virada Social”. A Secretaria Municipal de Saúde (SMS) e a Coordenadoria Regional de Saúde Sul (CRS Sul) participaram da “Jornada da Saúde” propiciando o acesso aos serviços de promoção e prevenção da saúde: elaboração do cartão SUS, alimentação saudável, medidas de pressão arterial, glicemia, vacinas, prevenção de gravidez precoce e doenças sexualmente transmissíveis (DST) para adolescentes, prevenção de câncer do colo de útero, dengue, saúde bucal e outras(AU)


Asunto(s)
Humanos , Salud Pública , Servicios de Salud , Salud de la Familia , Salud Mental , Organización y Administración
17.
Phys Rev Lett ; 107(15): 151801, 2011 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-22107284

RESUMEN

We present a search for the standard model Higgs boson and a fermiophobic Higgs boson in the diphoton final states based on 8.2 fb(-1) of pp collisions at sqrt[s]=1.96 TeV collected with the D0 detector at the Fermilab Tevatron Collider. No excess of data above background predictions is observed and upper limits at the 95% C.L. on the cross section multiplied by the branching fraction are set which are the most restrictive to date. A fermiophobic Higgs boson with a mass below 112.9 GeV is excluded at the 95% C.L.

18.
Phys Rev Lett ; 107(12): 121802, 2011 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-22026765

RESUMEN

We present a measurement of the ratio of top quark branching fractions R=B(t→Wb)/B(t→Wq), where q can be a d, s, or b quark, in the lepton+jets and dilepton tt final states. The measurement uses data from 5.4 fb(-1) of pp collisions collected with the D0 detector at the Fermilab Tevatron Collider. We measure R=0.90±0.04, and we extract the Cabibbo-Kobayashi-Maskawa (CKM) matrix element |V(tb)| as |V(tb)|=0.95±0.02, assuming unitarity of the 3×3 CKM matrix.

19.
Phys Rev Lett ; 107(12): 121801, 2011 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-22026764

RESUMEN

We report results from a search for neutral Higgs bosons produced in association with b quarks using data recorded by the D0 experiment at the Fermilab Tevatron Collider and corresponding to an integrated luminosity of 7.3 fb(-1). This production mode can be enhanced in several extensions of the standard model (SM) such as in its minimal supersymmetric extension (MSSM) at high tanß. We search for Higgs bosons decaying to tau pairs with one tau decaying to a muon and neutrinos and the other to hadrons. The data are found to be consistent with SM expectations, and we set upper limits on the cross section times branching ratio in the Higgs boson mass range from 90 to 320 GeV/c(2). We interpret our result in the MSSM parameter space, excluding tanß values down to 25 for Higgs boson masses below 170 GeV/c(2).

20.
Phys Rev Lett ; 107(8): 082004, 2011 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-21929164

RESUMEN

We measure the top quark mass (m(t)) in p ̄p collisions at a center of mass energy √s = 1.96 TeV using dilepton t ̄t→W(+)bW(-) ̄b→ℓ(+)ν(ℓ)bℓ(-) ̄ν(ℓ) ̄b events, where ℓ denotes an electron, a muon, or a tau that decays leptonically. The data correspond to an integrated luminosity of 5.4 fb(-1) collected with the D0 detector at the Fermilab Tevatron Collider. We obtain m(t)=174.0±1.8(stat)±2.4(syst) GeV, which is in agreement with the current world average m(t)=173.3±1.1 GeV. This is currently the most precise measurement of m(t) in the dilepton channel.

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