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1.
Adv Exp Med Biol ; 1410: 21-34, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36280657

RESUMO

Muscle mass and strength are subjected to several regulations. We found endocrine signals such as growth hormone, insulin-like growth factor 1, testosterone, thyroid hormones, and glucocorticoids among them. Neural inputs also influence muscle development, modulating mass and strength. Among the external stimuli that modulate these muscular features is physical training such as resistance and endurance training. Specifically, resistance training can mediate an increase in muscle mass by hypertrophy in adults, but the effects in children and adolescents are full of myths for most of the population. However, the evidence shows that the impact of resistance training on children and adolescents is clear and provides a wide range of benefits. However, qualified professionals must be available since exercise prescription and subsequent supervision must follow this population's abilities, needs, and interests.


Assuntos
Treinamento Resistido , Adulto , Humanos , Adolescente , Criança , Músculo Esquelético/metabolismo , Exercício Físico , Hipertrofia/metabolismo , Glucocorticoides , Testosterona/metabolismo , Força Muscular
2.
Phys Rev Lett ; 128(13): 132501, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35426696

RESUMO

We report the first measurement of the parity-violating elastic electron scattering asymmetry on ^{27}Al. The ^{27}Al elastic asymmetry is A_{PV}=2.16±0.11(stat)±0.16(syst) ppm, and was measured at ⟨Q^{2}⟩=0.02357±0.00010 GeV^{2}, ⟨θ_{lab}⟩=7.61°±0.02°, and ⟨E_{lab}⟩=1.157 GeV with the Q_{weak} apparatus at Jefferson Lab. Predictions using a simple Born approximation as well as more sophisticated distorted-wave calculations are in good agreement with this result. From this asymmetry the ^{27}Al neutron radius R_{n}=2.89±0.12 fm was determined using a many-models correlation technique. The corresponding neutron skin thickness R_{n}-R_{p}=-0.04±0.12 fm is small, as expected for a light nucleus with a neutron excess of only 1. This result thus serves as a successful benchmark for electroweak determinations of neutron radii on heavier nuclei. A tree-level approach was used to extract the ^{27}Al weak radius R_{w}=3.00±0.15 fm, and the weak skin thickness R_{wk}-R_{ch}=-0.04±0.15 fm. The weak form factor at this Q^{2} is F_{wk}=0.39±0.04.

3.
Phys Rev Lett ; 129(4): 042501, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35939025

RESUMO

We report a precise measurement of the parity-violating (PV) asymmetry A_{PV} in the elastic scattering of longitudinally polarized electrons from ^{48}Ca. We measure A_{PV}=2668±106(stat)±40(syst) parts per billion, leading to an extraction of the neutral weak form factor F_{W}(q=0.8733 fm^{-1})=0.1304±0.0052(stat)±0.0020(syst) and the charge minus the weak form factor F_{ch}-F_{W}=0.0277±0.0055. The resulting neutron skin thickness R_{n}-R_{p}=0.121±0.026(exp)±0.024(model) fm is relatively thin yet consistent with many model calculations. The combined CREX and PREX results will have implications for future energy density functional calculations and on the density dependence of the symmetry energy of nuclear matter.

4.
Phys Rev Lett ; 128(25): 252002, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35802440

RESUMO

We report high-precision measurements of the deeply virtual Compton scattering (DVCS) cross section at high values of the Bjorken variable x_{B}. DVCS is sensitive to the generalized parton distributions of the nucleon, which provide a three-dimensional description of its internal constituents. Using the exact analytic expression of the DVCS cross section for all possible polarization states of the initial and final electron and nucleon, and final state photon, we present the first experimental extraction of all four helicity-conserving Compton form factors (CFFs) of the nucleon as a function of x_{B}, while systematically including helicity flip amplitudes. In particular, the high accuracy of the present data demonstrates sensitivity to some very poorly known CFFs.

5.
Phys Rev Lett ; 128(10): 102002, 2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35333083

RESUMO

We present new precision measurements of the elastic electron-proton scattering cross section for momentum transfer (Q^{2}) up to 15.75 (GeV/c)^{2}. Combined with existing data, these provide an improved extraction of the proton magnetic form factor at high Q^{2} and double the range over which a longitudinal or transverse separation of the cross section can be performed. The difference between our results and polarization data agrees with that observed at lower Q^{2} and attributed to hard two-photon exchange (TPE) effects, extending to 8 (GeV/c)^{2} the range of Q^{2} for which a discrepancy is established at >95% confidence. We use the discrepancy to quantify the size of TPE contributions needed to explain the cross section at high Q^{2}.

6.
Phys Rev Lett ; 128(14): 142501, 2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35476486

RESUMO

We report precision determinations of the beam-normal single spin asymmetries (A_{n}) in the elastic scattering of 0.95 and 2.18 GeV electrons off ^{12}C, ^{40}Ca, ^{48}Ca, and ^{208}Pb at very forward angles where the most detailed theoretical calculations have been performed. The first measurements of A_{n} for ^{40}Ca and ^{48}Ca are found to be similar to that of ^{12}C, consistent with expectations and thus demonstrating the validity of theoretical calculations for nuclei with Z≤20. We also report A_{n} for ^{208}Pb at two new momentum transfers (Q^{2}) extending the previous measurement. Our new data confirm the surprising result previously reported, with all three data points showing significant disagreement with the results from the Z≤20 nuclei. These data confirm our basic understanding of the underlying dynamics that govern A_{n} for nuclei containing ≲50 nucleons, but point to the need for further investigation to understand the unusual A_{n} behavior discovered for scattering off ^{208}Pb.

7.
Rev Gastroenterol Peru ; 42(2): 131-135, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-36513360

RESUMO

Budd-Chiari syndrome is caused by an obstruction of blood flow to the liver. Published cases of the antiphospholipid syndrome associated with BCS are limited in the pediatric population. We report a 15-year-old adolescent who presented with fever, ascites, and hepatosplenomegaly. Hepatic Doppler ultrasound revealed no flow in the right and middle hepatic veins and in the inferior vena cava. Abdominal tomography revealed extensive thrombosis of the inferior vena cava. During hospitalization, she was diagnosed with antiphospholipid syndrome and systemic lupus erythematosus. She was given treatment with unfractionated heparin, low molecular weight heparin, and anticoagulants. Budd-Chiari syndrome secondary to the antiphospholipid syndrome is a life-threatening disease. Timely diagnosis and treatment improve the quality of life of the patient.


Assuntos
Síndrome Antifosfolipídica , Síndrome de Budd-Chiari , Lúpus Eritematoso Sistêmico , Feminino , Criança , Adolescente , Humanos , Síndrome de Budd-Chiari/etiologia , Síndrome de Budd-Chiari/complicações , Síndrome Antifosfolipídica/complicações , Síndrome Antifosfolipídica/diagnóstico , Heparina/uso terapêutico , Qualidade de Vida , Lúpus Eritematoso Sistêmico/complicações
8.
Phys Rev Lett ; 126(17): 172502, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33988387

RESUMO

We report a precision measurement of the parity-violating asymmetry A_{PV} in the elastic scattering of longitudinally polarized electrons from ^{208}Pb. We measure A_{PV}=550±16(stat)±8(syst) parts per billion, leading to an extraction of the neutral weak form factor F_{W}(Q^{2}=0.00616 GeV^{2})=0.368±0.013. Combined with our previous measurement, the extracted neutron skin thickness is R_{n}-R_{p}=0.283±0.071 fm. The result also yields the first significant direct measurement of the interior weak density of ^{208}Pb: ρ_{W}^{0}=-0.0796±0.0036(exp)±0.0013(theo) fm^{-3} leading to the interior baryon density ρ_{b}^{0}=0.1480±0.0036(exp)±0.0013(theo) fm^{-3}. The measurement accurately constrains the density dependence of the symmetry energy of nuclear matter near saturation density, with implications for the size and composition of neutron stars.

9.
Phys Rev Lett ; 127(15): 152301, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34678020

RESUMO

We report measurements of the exclusive neutral pion electroproduction cross section off protons at large values of x_{B} (0.36, 0.48, and 0.60) and Q^{2} (3.1 to 8.4 GeV^{2}) obtained from Jefferson Lab Hall A experiment E12-06-014. The corresponding structure functions dσ_{T}/dt+εdσ_{L}/dt, dσ_{TT}/dt, dσ_{LT}/dt, and dσ_{LT^{'}}/dt are extracted as a function of the proton momentum transfer t-t_{min}. The results suggest the amplitude for transversely polarized virtual photons continues to dominate the cross section throughout this kinematic range. The data are well described by calculations based on transversity generalized parton distributions coupled to a helicity flip distribution amplitude of the pion, thus providing a unique way to probe the structure of the nucleon.

10.
Phys Rev Lett ; 125(11): 112502, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32976004

RESUMO

A beam-normal single-spin asymmetry generated in the scattering of transversely polarized electrons from unpolarized nucleons is an observable related to the imaginary part of the two-photon exchange process. We report a 2% precision measurement of the beam-normal single-spin asymmetry in elastic electron-proton scattering with a mean scattering angle of θ_{lab}=7.9° and a mean energy of 1.149 GeV. The asymmetry result is B_{n}=-5.194±0.067(stat)±0.082 (syst) ppm. This is the most precise measurement of this quantity available to date and therefore provides a stringent test of two-photon exchange models at far-forward scattering angles (θ_{lab}→0) where they should be most reliable.

11.
J Vet Pharmacol Ther ; 39(4): 388-97, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26960624

RESUMO

Ribavirin is an antiviral used in human medicine, but it has not been authorized for use in veterinary medicine although it is effective against infectious salmon anemia (ISA) virus, between others. In this study, we present a pharmacokinetic profile of ribavirin in Atlantic salmon (Salmo salar), efficacy prediction indexes, and the measure of its withdrawal time. To determine the pharmacokinetic profile, fishes were orally administered with a single ribavirin dose of 1.6 mg/kg bw, and then, plasma concentrations were measured at different times. From the time-vs.-concentration curve, Cmax = 413.57 ng/mL, Tmax  = 6.96 h, AUC = 21394.01 µg·h/mL, t1/2  = 81.61 h, and K10  = 0.0421/h were obtained. Ribavirin reached adequate concentrations during the pharmacokinetic study, with prediction indexes of Cmax /IC50  = 20.7, AUC/IC50  = 1069.7, and T>IC50  = 71 h, where IC is the inhibitory concentration 50%. For ribavirin depletion study, fishes were orally administered with a dairy dose of 1.6 mg/kg bw during 10 days. Concentrations were measured on edible tissue on different days post-treatment. A linear regression of the time vs. concentration was conducted, obtaining a withdrawal time of 1966 °C days. Results obtained reveal that the dose of 1.6 mg/kg bw orally administered is effective for ISA virus, originating a reasonable withdrawal period within the productive schedules of Atlantic salmon.


Assuntos
Antivirais/farmacocinética , Músculo Esquelético/química , Ribavirina/farmacocinética , Salmo salar/metabolismo , Administração Oral , Ração Animal , Animais , Antivirais/administração & dosagem , Antivirais/sangue , Aquicultura , Resíduos de Drogas/análise , Resíduos de Drogas/farmacocinética , Ribavirina/administração & dosagem , Ribavirina/sangue
12.
Phys Rev Lett ; 113(2): 022502, 2014 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-25062169

RESUMO

We report the first measurement of the target-normal single-spin asymmetry in deep-inelastic scattering from the inclusive reaction 3)He(↑)(e,e')X on a polarized (3)He gas target. Assuming time-reversal invariance, this asymmetry is strictly zero in the Born approximation but can be nonzero if two-photon-exchange contributions are included. The experiment, conducted at Jefferson Lab using a 5.89 GeV electron beam, covers a range of 1.72 GeV, which is nonzero at the 2.89σ level. Our measured asymmetry agrees both in sign and magnitude with a two-photon-exchange model prediction that uses input from the Sivers transverse momentum distribution obtained from semi-inclusive deep-inelastic scattering.

13.
J Insect Sci ; 142014.
Artigo em Inglês | MEDLINE | ID: mdl-25527601

RESUMO

Adults and nymphs of the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), were collected in the Guayaquil, Samborondón, and Durán cantons in coastal Ecuador. Psyllids were found in high numbers in citrus (Citrus spp., Sapindales: Rutaceae) and orange jasmine (Murraya exotica [L.] Jack, Sapindales: Rutaceae) trees within the Guayaquil-Samborondon-Duran conurbation; however, none was found during scoutings in the main citrus producing areas in coastal Ecuador. To the best of our knowledge, this is the first report of D. citri in Ecuador and the Pacific coastal plain of South America.


Assuntos
Distribuição Animal , Citrus , Cadeia Alimentar , Hemípteros/fisiologia , Murraya , Animais , Citrus/crescimento & desenvolvimento , Equador , Hemípteros/crescimento & desenvolvimento , Murraya/crescimento & desenvolvimento , Ninfa/fisiologia , Densidade Demográfica
14.
Food Chem ; 444: 138709, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38350163

RESUMO

Melon landraces are highly appreciated by consumers who pay price premiums to compensate for lower yields, enabling on-farm conservation. However, they are highly susceptible to soilborne diseases. This study analyses the impact of Cucurbita and Cucumis rootstocks on the accumulation of flavor-related metabolites in Spanish landraces of the Ibericus melon group, as a strategy to promote their sustainable cultivation. Scion genotype was the main factor conditioning the accumulation of sugars and acids both under standard and saline organic farming conditions. The effects of grafting on organic acid accumulation were negligible, while the effects on sugar content were significant. The latter effects were dependent on specific scion-rootstock combinations, though wild Cucumis (e.g. Fian) rootstocks represent an alternative that should be further studied. The effect on the accumulation of volatiles was limited, and again depended on specific scion-rootstock combinations. The rootstock effect even differed between populations of the same landrace.


Assuntos
Cucumis , Cucurbita , Cucurbitaceae , Agricultura , Açúcares , Ácidos
15.
Phys Rev Lett ; 111(14): 141803, 2013 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-24152148

RESUMO

The Q(weak) experiment has measured the parity-violating asymmetry in ep elastic scattering at Q(2)=0.025(GeV/c)(2), employing 145 µA of 89% longitudinally polarized electrons on a 34.4 cm long liquid hydrogen target at Jefferson Lab. The results of the experiment's commissioning run, constituting approximately 4% of the data collected in the experiment, are reported here. From these initial results, the measured asymmetry is A(ep)=-279±35 (stat) ± 31 (syst) ppb, which is the smallest and most precise asymmetry ever measured in ep scattering. The small Q(2) of this experiment has made possible the first determination of the weak charge of the proton Q(W)(p) by incorporating earlier parity-violating electron scattering (PVES) data at higher Q(2) to constrain hadronic corrections. The value of Q(W)(p) obtained in this way is Q(W)(p)(PVES)=0.064±0.012, which is in good agreement with the standard model prediction of Q(W)(p)(SM)=0.0710±0.0007. When this result is further combined with the Cs atomic parity violation (APV) measurement, significant constraints on the weak charges of the up and down quarks can also be extracted. That PVES+APV analysis reveals the neutron's weak charge to be Q(W)(n)(PVES+APV)=-0.975±0.010.

16.
Allergy ; 68(8): 1076-80, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23888881

RESUMO

BACKGROUND: Polymorphisms of interleukin genes related to IgE production and inflammation are predictors of hypersensitivity to betalactam, but nothing is known on the influence of NOD genes, despite their association with inflammation and atopy. OBJECTIVE: To evaluate the association of NOD2 and NOD1 polymorphisms with betalactam allergy. METHOD: We genotyped 3 polymorphisms of NOD2 and 1 of NOD1 in 368 Italian and 387 Spanish patients, compared with 368 and 326 controls, respectively. RESULTS: CT/TT genotypes of rs2066845 of NOD2 predicted a lower risk in Italy (P = 0.003), while WT/insC genotype of rs5743293 (also in leucine-rich repeat domain) predicted a higher risk in Spain (P = 0.007). G allele of rs2066845 was associated with a higher level of IgE in the Italian population. CONCLUSION: The mirrored influence of these NOD2 polymorphisms on betalactam allergy in two populations suggests a link with pathways of inflammation and/or atopy through mechanisms, which need to be clarified.


Assuntos
Alérgenos/genética , Alérgenos/imunologia , Proteína Adaptadora de Sinalização NOD1/genética , Proteína Adaptadora de Sinalização NOD2/genética , Polimorfismo Genético/imunologia , beta-Lactamas/imunologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Hipersensibilidade/genética , Hipersensibilidade/imunologia , Hipersensibilidade/patologia , Imunoglobulina E/biossíntese , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem , beta-Lactamas/efeitos adversos
17.
Zoo Biol ; 32(5): 469-75, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23804545

RESUMO

Hand-rearing is a common practice for the propagation of captive psittacines, however, research on their nutrition is limited and the requirements of growing chicks are not well understood. The nutrition of 15 commercially available parrot hand-feeding formulas was compared with the average content of the crops of free living Scarlet Macaw (Ara macao) chicks, as well as with the requirements of 6- to 12-week-old leghorn chickens. When the formulas were prepared for a 1-week-old chick, all except three maintained >90% of solids in suspension after 15 min and >60 after 30 min. On average the formulas had a similar metabolizable energy density as wild macaw crop samples. The concentration of crude protein in the formulas was higher than that of the crop sample average, while the crude fat was lower than the average crop samples. More than 50% of the formulas had concentrations of K, Mg, and Mn less than the crop sample average, and Ca and Na concentrations below the requirements established for 6- to 12-week-old leghorn chickens. For >45% of the formulas the concentrations of arginine, leucine, and methionine + cystine were below the requirements of 6- to 12-week leghorns. When commercial formulas were prepared according to the manufacturer's instructions, the different dilutions greatly magnified the nutritional differences among them. Overall, the inconsistency in the nutrient concentrations among the formulas suggests that there is no consensus among manufacturers of the correct nutrition for growing psittacines and the industry could benefit from continued research in this area.


Assuntos
Ração Animal/análise , Criação de Animais Domésticos/métodos , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Métodos de Alimentação/veterinária , Papagaios/fisiologia , Animais , Cálcio/análise , Preferências Alimentares/fisiologia , Magnésio/análise , Manganês/análise , Potássio/análise , Sódio/análise
18.
Phys Rev Lett ; 108(22): 222004, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23180491

RESUMO

We present new data for the polarization observables of the final state proton in the (1)H(γ,p)π(0) reaction. These data can be used to test predictions based on hadron helicity conservation and perturbative QCD. These data have both small statistical and systematic uncertainties and were obtained with beam energies between 1.8 and 5.6 GeV and for π(0) scattering angles larger than 75° in the center-of-mass frame. The data extend the polarization measurements database for neutral pion photoproduction up to E(γ)=5.6 GeV. The results show a nonzero induced polarization above the resonance region. The polarization transfer components vary rapidly with the photon energy and π(0) scattering angle in the center-of-mass frame. This indicates that hadron helicity conservation does not hold and that the perturbative QCD limit is still not reached in the energy regime of this experiment.

19.
20.
J Vet Pharmacol Ther ; 35(1): 67-72, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21392039

RESUMO

Two groups of laying hens (each n=12) were administered 10 mg/kg enrofloxacin (ENRO) (group A) or 26.6 mg/kg flumequine (FLU) (group B) by gastric catheter daily for five consecutive days. A third group (n=6) was untreated controls. Eggs were collected from day one of treatment and up to 30 days after withdrawal of the drug. Egg white and yolk from each egg were separated, and ENRO, its metabolite ciprofloxacin (CIP) and FLU residues were analysed by a high-performance liquid chromatography method with fluorescence detection. The sum of ENRO and CIP was detectable in egg white on the first day of treatment in high-level concentrations (2007.7 µg/kg) and remained steady during administration. In egg yolk, residues were detectable at day one in lower concentrations (324.4 µg/kg), increasing to the end of treatment. After treatment, these residues decreased and were detectable up to day 8 in egg white, and day 10 in yolk. FLU residues during drug administration in white were detectable in high concentrations from day one to five (6788.4-6525.9 µg/kg), and in yolk, concentrations were lower during administration (629.6-853.9 µg/kg). After drug withdrawal, FLU residues remained longer in egg white (30 days) than in yolk (26 days). For both drugs, differences of concentrations between matrices were significant.


Assuntos
Galinhas/metabolismo , Resíduos de Drogas/análise , Ovos/análise , Fluoroquinolonas/farmacocinética , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacocinética , Ciprofloxacina/química , Ciprofloxacina/metabolismo , Ciprofloxacina/farmacocinética , Resíduos de Drogas/metabolismo , Enrofloxacina , Feminino , Fluoroquinolonas/metabolismo
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