338 research outputs found

    Axonal guidance using biofunctionalized silk fibroin fibers manufactured using the SFS technique

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    After an injury, the central nervous system's limited regenerative capacity severely hampers the reconnection and functional recovery of affected nervous tissue, making it an arduous task. To address this critical issue, biomaterials have emerged as a promising solution for designing scaffolds that facilitate and guide the regenerative process. Leveraging prior research on regenerated silk fibroin fibers produced via the straining flow spinning (SFS) technique, this study aims to demonstrate that biofunctionalized SFS fibers offer superior guidance capabilities compared to non- functionalized fibers. The study reveals that neurons' axons exhibit a remarkable tendency to align with the fibers' paths, in contrast to the isotropic growth observed on conventional culture plates. Additionally, the guidance ability of these fibers can be further enhanced through the biofunctionalization of the material with adhesion peptides. Proving the exceptional guidance potential of these fibers opens up exciting possibilities for their application as implants in spinal cord injuries. They could serve as a core component of a therapeutic approach that facilitates the reconnection of injured spinal cord ends, holding promise for significantly improving treatment outcomes in such cases.This study was partially funded by the Ministerio de Ciencia e InnovaciĂłn (PID2020-116403RB-I00; MCIN/AEI/10.13039/501100011033), Comunidad de Madrid (MINA-CM P2022-BMD-7236) and by the agreement between the Comunidad de Madrid (Spain) and the UPM through the REACT-UE funds of the European Regional Development Fund (ERDF), as a part of the response of the European Union to the SARS-CoV2 and COVID- 19 pandemic. It also has been financed by the UCM together with Banco Santander Scholarships (BOUC 11-23-2021; ref.: CT58/21-CT59/21)

    Fatigue Evaluation through Machine Learning and a Global Fatigue Descriptor

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    Research in physiology and sports science has shown that fatigue, a complex psychophysiological phenomenon, has a relevant impact in performance and in the correct functioning of our motricity system, potentially being a cause of damage to the human organism. Fatigue can be seen as a subjective or objective phenomenon. Subjective fatigue corresponds to a mental and cognitive event, while fatigue referred as objective is a physical phenomenon. Despite the fact that subjective fatigue is often undervalued, only a physically and mentally healthy athlete is able to achieve top performance in a discipline. )erefore, we argue that physical training programs should address the preventive assessment of both subjective and objective fatigue mechanisms in order to minimize the risk of injuries. In this context, our paper presents a machine-learning system capable of extracting individual fatigue descriptors (IFDs) from electromyographic (EMG) and heart rate variability (HRV) measurements. Our novel approach, using two types of biosignals so that a global (mental and physical) fatigue assessment is taken into account, reflects the onset of fatigue by implementing a combination of a dimensionless (0-1) global fatigue descriptor (GFD) and a support vector machine (SVM) classifier. )e system, based on 9 main combined features, achieves fatigue regime classification performances of 0.82 ± 0.24, ensuring a successful preventive assessment when dangerous fatigue levels are reached. Training data were acquired in a constant work rate test (executed by 14 subjects using a cycloergometry device), where the variable under study (fatigue) gradually increased until the volunteer reached an objective exhaustion state

    Spin-gravity coupling and gravity-induced quantum phases

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    External gravitational fields induce phase factors in the wave functions of particles. The phases are exact to first order in the background gravitational field, are manifestly covariant and gauge invariant and provide a useful tool for the study of spin-gravity coupling and of the optics of particles in gravitational or inertial fields. We discuss the role that spin-gravity coupling plays in particular problems.Comment: 18 pages, 1 figur

    Charm and hidden charm scalar mesons in the nuclear medium

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    We study the renormalization of the properties of low lying charm and hidden charm scalar mesons in a nuclear medium, concretely of the D_{s0}(2317) and the theoretical hidden charm state X(3700). We find that for the D_{s0}(2317), with negligible width at zero density, the width becomes about 100 MeV at normal nuclear matter density, while in the case of the X(3700) the width becomes as large as 200 MeV. We discuss the origin of this new width and trace it to reactions occurring in the nucleus, while offering a guideline for future experiments testing these changes. We also show how those medium modifications will bring valuable information on the nature of the scalar resonances and the mechanisms of the interaction of D mesons with nucleons and nuclei

    Impact of tetanus-diphtheria-acellular pertussis immunization during pregnancy on subsequent infant immunization seroresponses : follow-up from a large randomized placebo-controlled trial

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    Background: Pertussis immunization during pregnancy results in high pertussis antibody concentrations in young infants but may interfere with infant immune responses to post-natal immunization. Methods: This phase IV, multi-country, open-label study assessed the immunogenicity and safety of infant primary vaccination with DTaP-HepB-IPV/Hib and 13-valent pneumococcal conjugate vaccine (PCV13). Enrolled infants (6\u201314 weeks old) were born to mothers who were randomized to receive reduced-antigen-content diphtheria-tetanus-three-component acellular pertussis vaccine (Tdap group) or placebo (control group) during pregnancy (270/7\u2013366/7 weeks\u2019 gestation) with crossover immunization postpartum. All infants received 2 or 3 DTaP-HepB-IPV/Hib and PCV13 doses according to national schedules. Immunogenicity was assessed in infants pre- and 1 month post-primary vaccination. The primary objective was to assess seroprotection/vaccine response rates for DTaP-HepB-IPV/Hib antigens 1 month post-primary vaccination. Results: 601 infants (Tdap group: 296; control group: 305) were vaccinated. One month post-priming, seroprotection rates were 100% (diphtheria; tetanus), 6598.5% (hepatitis B), 6595.9% (polio) and 6594.5% (Hib) in both groups. Vaccine response rates for pertussis antigens were significantly lower in infants whose mothers received pregnancy Tdap (37.5\u201377.1%) versus placebo (90.0\u201399.2%). Solicited and unsolicited adverse event rates were similar between groups. Serious adverse events occurred in 2.4% (Tdap group) and 5.6% (control group) of infants, none were vaccination-related. Conclusions: Pertussis antibodies transferred during pregnancy may decrease the risk of pertussis infection in the first months of life but interfere with the infant's ability to produce pertussis antibodies, the clinical significance of which remains unknown. Safety and reactogenicity results were consistent with previous experience

    Critical exponents and equation of state of the three-dimensional Heisenberg universality class

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    We improve the theoretical estimates of the critical exponents for the three-dimensional Heisenberg universality class. We find gamma=1.3960(9), nu=0.7112(5), eta=0.0375(5), alpha=-0.1336(15), beta=0.3689(3), and delta=4.783(3). We consider an improved lattice phi^4 Hamiltonian with suppressed leading scaling corrections. Our results are obtained by combining Monte Carlo simulations based on finite-size scaling methods and high-temperature expansions. The critical exponents are computed from high-temperature expansions specialized to the phi^4 improved model. By the same technique we determine the coefficients of the small-magnetization expansion of the equation of state. This expansion is extended analytically by means of approximate parametric representations, obtaining the equation of state in the whole critical region. We also determine a number of universal amplitude ratios.Comment: 40 pages, final version. In publication in Phys. Rev.

    Gluon polarization in the nucleon from quasi-real photoproduction of high-pT hadron pairs

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    We present a determination of the gluon polarization Delta G/G in the nucleon, based on the helicity asymmetry of quasi-real photoproduction events, Q^2<1(GeV/c)^2, with a pair of large transverse-momentum hadrons in the final state. The data were obtained by the COMPASS experiment at CERN using a 160 GeV polarized muon beam scattered on a polarized 6-LiD target. The helicity asymmetry for the selected events is = 0.002 +- 0.019(stat.) +- 0.003(syst.). From this value, we obtain in a leading-order QCD analysis Delta G/G=0.024 +- 0.089(stat.) +- 0.057(syst.) at x_g = 0.095 and mu^2 =~ 3 (GeV}/c)^2.Comment: 10 pages, 3 figure

    The Deuteron Spin-dependent Structure Function g1d and its First Moment

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    We present a measurement of the deuteron spin-dependent structure function g1d based on the data collected by the COMPASS experiment at CERN during the years 2002-2004. The data provide an accurate evaluation for Gamma_1^d, the first moment of g1d(x), and for the matrix element of the singlet axial current, a0. The results of QCD fits in the next to leading order (NLO) on all g1 deep inelastic scattering data are also presented. They provide two solutions with the gluon spin distribution function Delta G positive or negative, which describe the data equally well. In both cases, at Q^2 = 3 (GeV/c)^2 the first moment of Delta G is found to be of the order of 0.2 - 0.3 in absolute value.Comment: fits redone using MRST2004 instead of MRSV1998 for G(x), correlation matrix adde

    Diversity of ferns and lycophytes in Brazil

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    This compilation of ferns and lycophytes in Brazil is an update of the one published in 2010 in CatĂĄlogo de Plantas e Fungos do Brasil. The methodology consisted in collecting data from regional checklists, taxonomic revisions, and selected databases. Invited specialists improved the list accessing a website housed at the Jardim BotĂąnico do Rio de Janeiro. The results show 1,253 species: 1,111 of ferns and 142 of lycophytes. This number is 6.5% higher than the previous one (1,176 spp.). The percentage of endemic species decreased from 38.2% to 36.7%. We recognized 36 families and 133 genera (vs. 33 families, 121 genera in 2010). The 10 most diverse families are Pteridaceae (196 spp.), Dryopteridaceae (179), Polypodiaceae (164), Hymenophyllaceae (90), Thelypteridaceae (86), Aspleniaceae (78), Lycopodiaceae (64), Selaginellaceae (55), Anemiaceae (51), and Cyatheaceae (45). The three most diverse genera are still Elaphoglossum (87 spp.), Thelypteris (85), and Asplenium (74). The richest phytogeographic domain continues to be in the Atlantic Rainforest with 883 species which also has the largest number of endemic and threatened species, followed by the Amazon Rainforest (503), Cerrado (269), Pantanal (30), Caatinga (26), and Pampa (eight). Minas Gerais remains as the richest state (657 spp. vs. 580 in 2010).Esta compilação de samambaias e licĂłfitas do Brasil Ă© uma atualização daquela de 2010, no CatĂĄlogo de Plantas e Fungos do Brasil. A metodologia consistiu na reuniĂŁo de dados de listas regionais, revisĂ”es de grupos e bancos de dados selecionados. Especialistas convidados melhoraram a lista atravĂ©s do acesso a um sĂ­tio da web do Jardim BotĂąnico do Rio Janeiro. Os resultados apontam uma diversidade de 1.253 espĂ©cies, sendo 1.111 samambaias e 142 licĂłfitas. Este nĂșmero Ă© 6,5% maior que o anterior (1.176 espĂ©cies). As espĂ©cies endĂȘmicas decresceram de 38,2% para 36,7%. Foram reconhecidas 36 famĂ­lias e 133 gĂȘneros (vs. 33 famĂ­lias, 121 gĂȘneros em 2010). As dez famĂ­lias mais diversas sĂŁo: Pteridaceae (196 espĂ©cies), Dryopteridaceae (179), Polypodiaceae (164), Hymenophyllaceae (90), Thelypteridaceae (86), Aspleniaceae (78), Lycopodiaceae (64), Selaginellaceae (55), Anemiaceae (51) e Cyatheaceae (45). Os trĂȘs gĂȘneros mais diversos continuam sendo Elaphoglossum (87 espĂ©cies), Thelypteris (85) e Asplenium (74). O DomĂ­nio FitogeogrĂĄfico mais rico continua sendo a Mata AtlĂąntica (883 espĂ©cies) e tambĂ©m com mais espĂ©cies endĂȘmicas e ameaçadas, seguido pela AmazĂŽnia (503 espĂ©cies), Cerrado (269), Pantanal (30), Caatinga (26) e Pampa (oito). Minas Gerais permanece como o estado com maior riqueza (657 espĂ©cies vs. 580 em 2010)

    A new measurement of the Collins and Sivers asymmetries on a transversely polarised deuteron target

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    New high precision measurements of the Collins and Sivers asymmetries of charged hadrons produced in deep-inelastic scattering of muons on a transversely polarised 6LiD target are presented. The data were taken in 2003 and 2004 with the COMPASS spectrometer using the muon beam of the CERN SPS at 160 GeV/c. Both the Collins and Sivers asymmetries turn out to be compatible with zero, within the present statistical errors, which are more than a factor of 2 smaller than those of the published COMPASS results from the 2002 data. The final results from the 2002, 2003 and 2004 runs are compared with naive expectations and with existing model calculations.Comment: 40 pages, 28 figure
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