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1.
Physica A ; 569: 125773, 2021 May 01.
Article in English | MEDLINE | ID: mdl-33495669

ABSTRACT

We study the spreading of SARS-CoV-2 in Brazil based on official data available since March 22, 2020. Calculations are done via an adaptive susceptible-infected-removed (SIR) model featuring dynamical recuperation and propagation rates. We are able reproduce the number of confirmed cases over time with less than 5% error and also provide with short- and long-term predictions. The model can also be used to account for the epidemic dynamics in other countries with great accuracy.

2.
Eur J Sport Sci ; 21(4): 481-496, 2021 Apr.
Article in English | MEDLINE | ID: mdl-32297547

ABSTRACT

In professional soccer, increasing amounts of data are collected that harness great potential when it comes to analysing tactical behaviour. Unlocking this potential is difficult as big data challenges the data management and analytics methods commonly employed in sports. By joining forces with computer science, solutions to these challenges could be achieved, helping sports science to find new insights, as is happening in other scientific domains. We aim to bring multiple domains together in the context of analysing tactical behaviour in soccer using position tracking data. A systematic literature search for studies employing position tracking data to study tactical behaviour in soccer was conducted in seven electronic databases, resulting in 2338 identified studies and finally the inclusion of 73 papers. Each domain clearly contributes to the analysis of tactical behaviour, albeit in - sometimes radically - different ways. Accordingly, we present a multidisciplinary framework where each domain's contributions to feature construction, modelling and interpretation can be situated. We discuss a set of key challenges concerning the data analytics process, specifically feature construction, spatial and temporal aggregation. Moreover, we discuss how these challenges could be resolved through multidisciplinary collaboration, which is pivotal in unlocking the potential of position tracking data in sports analytics.


Subject(s)
Athletic Performance/statistics & numerical data , Big Data , Data Analysis , Soccer/statistics & numerical data , Data Management , Humans , Informatics
3.
Sci Rep ; 10(1): 8620, 2020 05 25.
Article in English | MEDLINE | ID: mdl-32451399

ABSTRACT

Besides technical and tactical aspects, basketball matches involve high aerobic and anaerobic capacities, conferring the final performance of a team. Thus, the evaluation of physical and technical responses is an effective way to predict the performance of athletes. Field and laboratory tests have been used in sports. The first involving high ecological validity and low cost, and the second, greater control and accuracy but not easy application, considering the different preparation phases in a season. This study aimed, through complex networks analysis, to verify whether centrality parameters analysed from significant correlations behave similarly in distinct scenarios (laboratory and on-court), emphasizing aerobic and anaerobic physical parameters and technical performances. The results showed that, in a compelling  analysis involving basketball athletes, the studied centralities (degree, betweenness, eigenvector and pagerank) revealed similar responses in both scenarios, which is widely attractive considering the greater financial economy and lower time when applying tests in the field.

4.
Arq. bras. med. vet. zootec. (Online) ; 71(3): 990-996, May-June 2019. tab
Article in Portuguese | VETINDEX, LILACS | ID: biblio-1011324

ABSTRACT

Objetivou-se avaliar o efeito de complexos enzimáticos sobre a energia metabolizável e o coeficiente de digestibilidade de nutrientes do milheto para frangos de corte. Quinhentos e setenta e seis frangos machos foram distribuídos em 36 gaiolas, com três tratamentos: T1 - composição de milheto sem complexo enzimático; T2 - composição de milheto com complexo enzimático (CES) e T3 - composição de milheto com complexo enzimático (CEV). Os tratamentos foram definidos com base em seis dietas (três dietas referências e três dietas testes). As dietas testes foram obtidas pela substituição de 40% da dieta referência por milheto inteiro, e a adição de enzimas consistiu de dois complexos enzimáticos: CES, constituído pelas enzimas fitase, protease, xilanase, ß-glucanase, celulase, amilase e pectinase; e CEV. constituído pelas enzimas protease, celulase e amilase. Na fase de 11 a 20 dias, a suplementação com o CEV reduziu os valores de EMA, EMAn e CDPB. A suplementação com CES melhorou o CDPB, e não houve efeito significativo para CDMS e CDEB. Na fase de 21 a 30 dias, houve menor aproveitamento da energia e dos nutrientes com as suplementações CES e CEV. Na fase de 31 a 40 dias, as suplementações reduziram os valores de EMA, EMAn, e o complexo CEV foi efetivo em aumentar o valor de CDPB. A inclusão dos complexos enzimáticos CES (fitase, protease, xilanase, ß-glucanase, celulase, amilase e pectinase) e CEV (protease, celulase e amilase) não favoreceu a utilização da energia do milheto, no entanto melhorou o coeficiente de digestibilidade da proteína do milheto nos períodos de 11 a 20 e de 31 a 40 dias de idade.(AU)


The objective of this study was to evaluate the effect of enzymatic complexes on metabolizable energy and nutrient digestibility coefficient of millet for broilers chickens. 576 male chickens, were distributed in 36 cages with three treatments: T1 - millet composition without enzymatic complex; T2 - millet composition with enzymatic complex (ECS); and T3 - millet composition with enzymatic complex (ECV). The treatments were defined from six diets (3 reference diets and 3 test diets). The test diets were obtained from the substitution of 40% for reference diet by whole millet, and the enzyme addition consisted of two enzymatic complex, ECS constituted by phytase, protease, xylanase, ß-glucanase, cellulase, amylase and pectinase enzymes, and ECV constituted by protease, cellulase and amylase enzymes. In the 11 to 20 days phase, a supplementation with the ECV reduced the AME, AMEn and CDPB values, a ECS supplementation improved the CDPB, and there was no significant effect for CDMS and CDEB. In the 21 to 30 days phase, there were less profit of the energy and nutrients with ECS and ECV supplements. In the 31 to 40 days phase as supplements reduced the values of AME, AMEn, and the ECV complex was effective in increasing the value of CDPB. The inclusion of ECS enzymatic complexes, (phytase, protease, xylanase, ß-glucanase, cellulase, amylase and pectinase) and ECV (protease, cellulase and amylase), did not favor millet's energy utilization, however, favored the millet's protein digestibility coefficient on 11 to 20 and 31 to 40 periods.(AU)


Subject(s)
Animals , Male , Chickens , Enzymes , Millets , Animal Feed/analysis , Digestion
5.
Phys Rev E ; 99(2-1): 022117, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30934307

ABSTRACT

We study the effects of spatially long-range correlated phase disorder on the Hadamard quantum walk on a line. The shift operator is built to exhibit an intrinsic disorder distribution featuring long-range correlations. To impose such, we resort to fractional Brownian motion with power-law spectrum 1/k^{2α} with α≥0 being the exponent that controls the degree of correlations. We discuss the scaling behavior of the walker's wave packet and report a localization-delocalization transition controlled by α. We unveil two intermediate dynamical regimes between exponential localization and full delocalization.

6.
Nutr Metab Cardiovasc Dis ; 28(9): 865-876, 2018 09.
Article in English | MEDLINE | ID: mdl-30111493

ABSTRACT

AIMS: To determine whether oral antioxidant therapies, of various types and doses, are able to prevent or treat women with preeclampsia. DATA SYNTHESIS: The following databases were searched: MEDLINE, CENTRAL, LILACS, and Web of Science. Inclusion criteria were: a) randomized clinical trials; b) oral antioxidant supplementation; c) study in pregnant women; d) control group, treated or not with placebo. Papers were excluded if they evaluated antioxidant nutrient supplementation associated with other non-antioxidant therapies. Data were extracted and the risk of bias of each study was assessed. Heterogeneity was analyzed using the Cochran Q test, and I2 statistics and pre-specified sensitivity analyses were performed. Meta-analyses were conducted on prevention and treatment studies, separately. The primary outcome was the incidence of preeclampsia in prevention trials, and of perinatal death in treatment trials. Twenty-nine studies were included in the analysis, 19 for prevention and 10 for treatment. The antioxidants used in these studies were vitamins C and E, selenium, l-arginine, allicin, lycopene and coenzyme Q10, none of which showed beneficial effects on the prevention of preeclampsia (RR: 0.89, CI 95%: [0.79-1.02], P = 0.09; I2 = 39%, P = 0.04) and other outcomes. The antioxidants used in the treatment studies were vitamins C and E, N-acetylcysteine, l-arginine, and resveratrol. A beneficial effect was found in intrauterine growth restriction. CONCLUSIONS: Antioxidant therapy had no effects in the prevention of preeclampsia but did show beneficial effects in intrauterine growth restriction, when used in the treatment of this condition.


Subject(s)
Antihypertensive Agents/administration & dosage , Antioxidants/administration & dosage , Blood Pressure/drug effects , Pre-Eclampsia/drug therapy , Pre-Eclampsia/prevention & control , Administration, Oral , Adolescent , Adult , Antihypertensive Agents/adverse effects , Antioxidants/adverse effects , Evidence-Based Medicine , Female , Fetal Growth Retardation/prevention & control , Humans , Incidence , Pre-Eclampsia/mortality , Pre-Eclampsia/physiopathology , Pregnancy , Randomized Controlled Trials as Topic , Risk Factors , Treatment Outcome , Young Adult
7.
Phys Chem Chem Phys ; 20(19): 13145-13152, 2018 May 16.
Article in English | MEDLINE | ID: mdl-29498384

ABSTRACT

Molecularly imprinted polymers are advanced recognition materials selectively rebinding a target molecule present during the synthesis of the polymer matrix. It is commonly understood that the templating process is based on embedding the complex formed between a template and functional monomers into a co-polymer matrix. This happens by a polymerization of the complex with a cross-linker while maintaining their spatial arrangement forming a molecular imprint. Template removal then leads to synthetic recognition sites ready to selectively rebind their targets, which are complementary in functionality, size and shape to the target. In this study, an innovative theoretical concept using fully atomistic molecular dynamics simulations for modeling molecular templating processes is introduced yielding virtually imprinted polymers (VIPs). VIPs created for the template 17-ß-estradiol and applied in modeled chromatography experiments demonstrated selectivity for their template. This evidenced the creation of virtual imprints as a result of a templated synthesis protocol, which represents a theoretical confirmation of the governing imprinting theory.

8.
Phys Chem Chem Phys ; 20(19): 13153-13158, 2018 May 16.
Article in English | MEDLINE | ID: mdl-29517773

ABSTRACT

Synthetic molecular recognition materials, such as molecularly imprinted polymers (MIPs), are of increasing importance in biotechnology and analytical chemistry, as they are able to selectively bind their respective template. However, due to their specificity, each MIP has to be individually designed for the desired target leading to a molecularly tailored synthesis strategy. While trial-and-error remains the common approach for selecting suitable functional monomers (FMs), the study herein introduces a radically new approach towards rationally designing MIPs by rapidly screening suitable functional monomers based on local density of states (LDOS) calculations in a technique known as Electronic Indices Methodology (EIM). An EIM-based method of classification of FMs according to their suitability for imprinting was developed. Starting from a training set of nine different functional monomers, the prediction of suitability of four functional monomers was possible. These predictions were subsequently experimentally confirmed.

9.
Phys Rev E ; 95(5-1): 052217, 2017 May.
Article in English | MEDLINE | ID: mdl-28618533

ABSTRACT

We consider interacting electrons moving in a nonlinear Morse lattice. We set the initial conditions as follows: electrons were initially localized at the center of the chain and a solitonic deformation was produced by an impulse excitation on the center of the chain. By solving quantum and classical equations for this system numerically, we found that a fraction of electronic wave function was trapped by the solitonic excitation, and trapping specificities depend on the degree of interaction among electrons. Also, there is evidence that the effective electron velocity depends on Coulomb interaction and electron-phonon coupling in a nontrivial way. This association is explained in detail along this work. In addition, we briefly discuss the dependence of our results with the type of initial condition we choose for the electrons and lattice.

10.
Int J Sports Med ; 37(12): 992-996, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27479459

ABSTRACT

Soccer matches consist of a variety of different activities, including repeated sprints. Time to attain velocity (TTAV), load range (LR) and the torque-angle-velocity relationship (TAV3D) represent an important measurement of muscle performance, however there are few related studies. The aim of this study was to compare these outcomes between soccer players of different age category. 17 professional (PRO) and 17 under-17 (U17) soccer players were assessed for concentric knee flexion/extension at 60, 120 and 300°/s. For the extensor muscles, differences were found in favor of the U17 group for TTAV and LR outcomes at 120°/s, however, the PRO group maintained higher torques in both movement directions in comparison to the U17 in TAV3D evaluation. These results suggest that muscle performance of the PRO group is more efficient than the U17 group.


Subject(s)
Knee Joint/physiology , Muscle, Skeletal/physiology , Running/physiology , Soccer/physiology , Adolescent , Adult , Age Factors , Athletes , Athletic Performance/physiology , Humans , Time Factors , Torque , Young Adult
11.
Science ; 349(6246): 400-4, 2015 Jul 24.
Article in English | MEDLINE | ID: mdl-26206929

ABSTRACT

Superelastic conducting fibers with improved properties and functionalities are needed for diverse applications. Here we report the fabrication of highly stretchable (up to 1320%) sheath-core conducting fibers created by wrapping carbon nanotube sheets oriented in the fiber direction on stretched rubber fiber cores. The resulting structure exhibited distinct short- and long-period sheath buckling that occurred reversibly out of phase in the axial and belt directions, enabling a resistance change of less than 5% for a 1000% stretch. By including other rubber and carbon nanotube sheath layers, we demonstrated strain sensors generating an 860% capacitance change and electrically powered torsional muscles operating reversibly by a coupled tension-to-torsion actuation mechanism. Using theory, we quantitatively explain the complementary effects of an increase in muscle length and a large positive Poisson's ratio on torsional actuation and electronic properties.


Subject(s)
Elastic Tissue , Electronics , Muscle, Skeletal , Nanotubes, Carbon , Elasticity , Electric Capacitance , Torsion, Mechanical
12.
J Phys Condens Matter ; 27(17): 175401, 2015 May 08.
Article in English | MEDLINE | ID: mdl-25836635

ABSTRACT

In this work, we study the vibrational modes and energy spreading in a harmonic chain model with diluted second-neighbors couplings and correlated mass-spring disorder. While all nearest neighbor masses are coupled by an elastic spring, second neighbors springs are introduced with a probability pD. The masses are randomly distributed according to the site connectivity mi = m0 (1 + 1/n(α)(I), where ni is the connectivity of the site i and α is a tunable exponent. We show that maximum localization of the vibrational modes is achieved for α ≃ 3/4. The time-evolution of the energy wave-packet is followed after an initial localized excitation. While the participation number remains finite, the energy spread is shown to be sub-diffusive after a displacement and super-diffusive after an impulse excitation. These features are related to the development of a power-law tail in the wave-packet distribution. Further, we unveil that the spring dilution leads to the emergence of a resonant localized state which is signaled by a van Hove singularity in the density of states.

13.
J Phys Condens Matter ; 27(3): 035104, 2015 Jan 28.
Article in English | MEDLINE | ID: mdl-25564495

ABSTRACT

We investigate the electronic wavepacket dynamics in a finite segment of a DNA single-strand chain considering the electron-phonon coupling. Our theoretical approach makes use of an effective tight-binding Hamiltonian to describe the electron dynamics, together with a classical harmonic Hamiltonian to treat the intrinsic DNA vibrations. An effective time-dependent Schrödinger equation is then settled up and solved numerically for an initially localized wave-packet using the standard Dormand-Prince eighth-order Runge-Kutta method. Our numerical results indicate the presence of a sub-diffusive electronic wavepacket spread mediated by the electron-phonon interaction.


Subject(s)
DNA, Single-Stranded/chemistry , Phonons , Diffusion , Electron Transport
14.
Free Radic Res ; 49(2): 199-203, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25465091

ABSTRACT

INTRODUCTION: Cholesterol undergoes oxidation via both enzymatic stress- and free radical-mediated mechanisms, generating a wide range of oxysterols. In contrast to oxidative stress-driven metabolites, enzymatic stress-derived oxysterols are scarcely studied in their association with atherosclerotic disease in humans. METHODS: 24S-hydroxycholesterol (24S-HC), 25-hydroxycholesterol (25-HC), and 27-hydroxycholesterol (27-HC) were assessed in plasma and arteries with atherosclerotic plaques from 10 patients (54-84 years) with severe peripheral artery disease (PAD) as well as arteries free of atherosclerotic plaques from 13 individuals (45-78 years, controls). RESULTS: Plasma 25-HC was higher in PAD individuals than in controls (6.3[2] vs. 3.9[1.9] ng/mgCol; p = 0.004). 24S-HC and 27-HC levels were, respectively, five- and 20-fold higher in the arterial tissue of PAD individuals than in those of the controls (p = 0.016 and p = 0.001). Plasma C-reactive protein correlated with plasma 24-HC (r = 0.51; p = 0.010), 25-HC (r = 0.75; p < 0.001), 27-HC (r = 0.48; p = 0.015), and with tissue 24S-HC (r = 0.4; p = 0.041) and 27-HC (r = 0.46; p = 0.023). CONCLUSION: Arterial intima accumulation of 27-HC and 24S-HC is associated with advanced atherosclerotic disease and systemic inflammatory activity in individuals with severe PAD.


Subject(s)
Arteries/chemistry , Hydroxycholesterols/blood , Inflammation/blood , Peripheral Arterial Disease/blood , Aged , Aged, 80 and over , C-Reactive Protein/analysis , Female , Humans , Male , Middle Aged
15.
Article in English | MEDLINE | ID: mdl-25353765

ABSTRACT

The Bose-Einstein condensation of noninteracting particles restricted to move on the sites of hierarchical diamond lattices is investigated. Using a tight-binding single-particle Hamiltonian with properly rescaled hopping amplitudes, we are able to employ an orthogonal basis transformation to exactly map it on a set of decoupled linear chains with sizes and degeneracies written in terms of the network branching parameter q and generation number n. The integrated density of states is shown to have a fractal structure of gaps and degeneracies with a power-law decay at the band bottom. The spectral dimension d(s) coincides with the network topological dimension d(f) = ln(2q)/ln(2). We perform a finite-size scaling analysis of the fraction of condensed particles and specific heat to characterize the critical behavior of the BEC transition that occurs for q > 2 (d(s) > 2). The critical exponents are shown to follow those for lattices with a pure power-law spectral density, with non-mean-field values for q < 8 (d(s) < 4). The transition temperature is shown to grow monotonically with the branching parameter, obeying the relation 1/T(c) = a + b/(q - 2).


Subject(s)
Colloids/chemistry , Crystallization/methods , Elementary Particles , Models, Chemical , Models, Molecular , Computer Simulation , Phase Transition , Thermodynamics
16.
J Phys Condens Matter ; 26(41): 415401, 2014 Oct 15.
Article in English | MEDLINE | ID: mdl-25244998

ABSTRACT

In our work, we consider the problem of electronic transport mediated by coupling with solitonic elastic waves. We study the electronic transport in a 1D unharmonic lattice with a cubic interaction between nearest neighboring sites. The electron-lattice interaction was considered as a linear function of the distance between neighboring atoms in our study. We numerically solve the dynamics equations for the electron and lattice and compute the dynamics of an initially localized electronic wave-packet. Our results suggest that the solitonic waves that exist within this nonlinear lattice can control the electron dynamics along the chain. Moreover, we demonstrate that the existence of a mobile electron-soliton pair exhibits a counter-intuitive dependence with the value of the electron-lattice coupling.

17.
Article in English | MEDLINE | ID: mdl-24032807

ABSTRACT

We show that the ideal Boson gas displays a finite-temperature Bose-Einstein condensation transition in the complex Apollonian network exhibiting scale-free, small-world, and hierarchical properties. The single-particle tight-binding Hamiltonian with properly rescaled hopping amplitudes has a fractal-like energy spectrum. The energy spectrum is analytically demonstrated to be generated by a nonlinear mapping transformation. A finite-size scaling analysis over several orders of magnitudes of network sizes is shown to provide precise estimates for the exponents characterizing the condensed fraction, correlation size, and specific heat. The critical exponents, as well as the power-law behavior of the density of states at the bottom of the band, are similar to those of the ideal Boson gas in lattices with spectral dimension d(s)=2ln(3)/ln(9/5)~/=3.74.

18.
J Phys Condens Matter ; 24(49): 495401, 2012 Dec 12.
Article in English | MEDLINE | ID: mdl-23148043

ABSTRACT

In this paper we study a one-dimensional ternary harmonic chain with the mass distribution constructed from an Ornstein-Uhlenbeck process. We generate a ternary mass disordered distribution by generating the correlated Ornstein-Uhlenbeck process and mapping it into a sequence of three different values. The probability of each value is controlled by a fixed parameter b. We analyze the localization aspect of the above model by numerical solution of the Hamilton equations and by the transfer matrix formalism. Our results indicate that the correlated ternary mass distribution does not promote the appearance of new extended modes. In good agreement with previous work, we obtain extended modes for b â†’ ∞; however, we explain in detail the main issue behind this apparent localization- delocalization transition. In addition, we obtain the energy dynamics for this classical chain.

19.
J Phys Condens Matter ; 24(24): 245401, 2012 Jun 20.
Article in English | MEDLINE | ID: mdl-22592338

ABSTRACT

In this paper we report new numerical results on the disordered Schrödinger equation with nonlinear hopping. By using a classical harmonic Hamiltonian and the Su-Schrieffer-Heeger approximation we write an effective Schrödinger equation. This model with off-diagonal nonlinearity allows us to study the interaction of one electron and acoustical phonons. We solve the effective Schrödinger equation with nonlinear hopping for an initially localized wavepacket by using a predictor-corrector Adams-Bashforth-Moulton method. Our results indicate that the nonlinear off-diagonal term can promote a long-time subdiffusive regime similar to that observed in models with diagonal nonlinearity.

20.
J Phys Condens Matter ; 24(20): 205401, 2012 May 23.
Article in English | MEDLINE | ID: mdl-22510663

ABSTRACT

We investigate the nature of one-electron eigenstates in power-law-diluted chains for which the probability of occurrence of a bond between sites separated by a distance r decays as p(r) = p/r(1+σ). Using an exact diagonalization scheme and a phenomenological finite-size scaling analysis, we determine the quantum percolation transition phase diagram in the full parameter space (p,σ). We show that the density of states displays singularities at some resonance energies associated with degenerate eigenstates localized in a pair of sites with special symmetries. This model is shown to present an intermediate phase for which there is classical percolation but no quantum percolation. Quantum percolation only takes place for σ < 0.78, a value larger than the corresponding one for the Anderson transition in long-ranged coupled chains with random diagonal disorder. The fractality of critical wavefunctions is also characterized.

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