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1.
Vopr Pitan ; 89(4): 220-232, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32986335

RESUMO

Fruits and berries are the most important sources of a wide range of biologically active substances, including vitamin C, carotenoids, flavonoids, anthocyanins. In order to replenish and update data on the content of food and biologically active substances in the tables of the chemical composition of food products, a study of the content of mono- and disaccharides, dietary fiber was carried out; vitamins C, B1, B2 and E, minerals and trace elements; flavonoids (in terms of rutin), anthocyanins; organic and hydroxycinnamic acids, stilbenoids in various varieties of 16 fruit and berry crops. Material and methods. The material for the study was the fruits of promising varieties and selected forms of pome fruit (apple, pear), stone fruit (cherry, plum, apricot), berry (garden strawberry, raspberry, black currant, red currant, gooseberry), non-traditional crops (actinidia, honeysuckle, cornelian cherry, viburnum, sea buckthorn, rosehip) - a total of 208 samples grown at the I.V. Michurin Federal Scientific Center. The B vitamins were determined by the fluorometric method, and vitamin E, organic and hydroxycinnamic acids, carbohydrates, and stilbenoids were determined by HPLC. The amount of anthocyanin pigments was determined by pH differential spectrophotometry, dietary fiber - by enzymatic-gravimetric method, flavonoids - spectrophotometrically. Results and discussion. The main carbohydrate of apricot is sucrose, black currants, cherries, raspberries and honeysuckle contain mainly fructose and glucose. Raspberries and currants are high in fiber. Comparison of the obtained data on the content of vitamins B1, B2, E, flavonoids and anthocyanins in the studied population of varieties in comparison with the published data of tables of the chemical composition of food products in the USA and Russia was carried out. By the content of vitamin C in descending order, the fruits are arranged in a row: black currant > sea buckthorn > honeysuckle > strawberry > red currant > viburnum > gooseberry > raspberry > apple. Berries, making a significant contribution to providing the body with vitamin C, are not an essential source of vitamins B and E. The inclusion of 100 g of fresh fruit in the diet provides about 10% of the recommended dietary intake for potassium (apricot, gooseberry, cherry and black currant), magnesium (apple, cherry, strawberry) and dietary fiber. Honeysuckle and black currant are high in anthocyanins; consumption of 100 g of these berries will ensure adequate intake of these micronutrients. Some varieties of strawberries, apples and pears are rich in hydroxycinnamic acids. The data obtained can be used to refine the indicators in the existing tables of the chemical composition of food products. Conclusion. The obtained data on the composition of fruit and berry products will make it possible to more correctly calculate the nutritional value of rations using questionnaire-survey methods. Combined analysis of the composition of biologically active substances in berries and fruits makes it possible to more reasonably make the choice of a particular product in the dietary correction of the ration of healthy and sick people.


Assuntos
Antocianinas/análise , Fibras na Dieta/análise , Frutas/química , Minerais/análise , Valor Nutritivo , Análise de Alimentos , Humanos , Federação Russa
2.
Phys Rev Lett ; 111(11): 111801, 2013 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-24074072

RESUMO

We measure the mass difference Δm0 between the D*(2010)+ and the D0 and the natural linewidth Γ of the transition D*(2010)+ → D0π+. The data were recorded with the BABAR detector at center-of-mass energies at and near the Υ(4S) resonance, and correspond to an integrated luminosity of approximately 477 fb(-1). The D0 is reconstructed in the decay modes D0 → K- π+ and D0 → K- π+ π- π+. For the decay mode D0 → K- π+ we obtain Γ = (83.4±1.7±1.5) keV and Δm0 = (145425.6±0.6±1.7) keV, [corrected] where the quoted errors are statistical and systematic, respectively. For the D0 → K- π+ π- π+ mode we obtain Γ = (83.2±1.5±2.6) keV and Δm0 = (145426.6±0.5±1.9) keV. [corrected] The combined measurements yield Γ = (83.3±1.2±1.4) keV and Δm0 = (145425.9±0.4±1.7) keV; the width is a factor of approximately 12 times more precise than the previous value, while the mass difference is a factor of approximately 6 times more precise.

3.
Phys Rev Lett ; 111(10): 101802, 2013 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-25166652

RESUMO

We present results of a search for CP violation in B0- B0 mixing with the BABAR detector. We select a sample of B0→D*- Xℓ+ ν decays with a partial reconstruction method and use kaon tagging to assess the flavor of the other B meson in the event. We determine the CP violating asymmetry ACP≡[N(B0B0)-N(B0B0)]/[N(B0B0)+N(B0B0)]=(0.06±0.17(-0.32)(+0.38))%, corresponding to ΔCP=1-|q/p|=(0.29±0.84(-1.61)(+1.88))×10(-3).

4.
Phys Rev Lett ; 109(19): 191801, 2012 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-23215373

RESUMO

The photon spectrum in the inclusive electromagnetic radiative decays of the B meson, B → X(s)γ plus B → X(d)γ, is studied using a data sample of (382.8 ± 4.2) × 10(6)Υ(4S) → BB decays collected by the BABAR experiment at SLAC. The spectrum is used to extract the branching fraction B(B → X(s)γ) = (3.21 ± 0.33) × 10(-4) for E(γ) >1.8 GeV and the direct CP asymmetry A(CP) (B → X(s+d)γ) = 0.057 ± 0.063. The effects of detector resolution and Doppler smearing are unfolded to measure the photon energy spectrum in the B meson rest frame.


Assuntos
Modelos Teóricos , Física Nuclear/métodos , Fótons , Mésons , Energia Nuclear
5.
Phys Rev Lett ; 109(21): 211801, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23215586

RESUMO

Although CP violation in the B meson system has been well established by the B factories, there has been no direct observation of time-reversal violation. The decays of entangled neutral B mesons into definite flavor states (B(0) or B(0)), and J/ψK(L)(0) or ccK(S)(0) final states (referred to as B(+) or B(-)), allow comparisons between the probabilities of four pairs of T-conjugated transitions, for example, B(0) → B(-) and B(-) → B(0), as a function of the time difference between the two B decays. Using 468 × 10(6) BB pairs produced in Υ(4S) decays collected by the BABAR detector at SLAC, we measure T-violating parameters in the time evolution of neutral B mesons, yielding ΔS(T)(+) = -1.37 ± 0.14(stat) ± 0.06(syst) and ΔS(T)(-) = 1.17 ± 0.18(stat) ± 0.11(syst). These nonzero results represent the first direct observation of T violation through the exchange of initial and final states in transitions that can only be connected by a T-symmetry transformation.

6.
Phys Rev Lett ; 109(10): 101802, 2012 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-23005279

RESUMO

Based on the full BABAR data sample, we report improved measurements of the ratios R(D(*))=B(B[over ¯]→D(*)τ(-)ν[over ¯](τ))/B(B[over ¯]→D(*)ℓ(ℓ)(-)ν[over ¯](ℓ)), where ℓ is either e or µ. These ratios are sensitive to new physics contributions in the form of a charged Higgs boson. We measure R(D)=0.440±0.058±0.042 and R(D(*))=0.332±0.024±0.018, which exceed the standard model expectations by 2.0σ and 2.7σ, respectively. Taken together, our results disagree with these expectations at the 3.4σ level. This excess cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model.

7.
Phys Rev Lett ; 108(21): 211801, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-23003239

RESUMO

Recent astrophysical and terrestrial experiments have motivated the proposal of a dark sector with GeV-scale gauge boson force carriers and new Higgs bosons. We present a search for a dark Higgs boson using 516 fb(-1) of data collected with the BABAR detector. We do not observe a significant signal and we set 90% confidence level upper limits on the product of the standard model-dark-sector mixing angle and the dark-sector coupling constant.

8.
Phys Rev Lett ; 107(22): 221803, 2011 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-22182022

RESUMO

We search for hadronic decays of a light Higgs boson (A(0)) produced in radiative decays of an Υ(2S) or Υ(3S) meson, Υ→γA(0). The data have been recorded by the BABAR experiment at the Υ(3S) and Υ(2S) center-of-mass energies and include (121.3±1.2)×10(6) Υ(3S) and (98.3±0.9)×10(6) Υ(2S) mesons. No significant signal is observed. We set 90% confidence level upper limits on the product branching fractions B(Υ(nS)→γA(0))B(A(0)→hadrons) (n=2 or 3) that range from 1×10(-6) for an A(0) mass of 0.3 GeV/c(2) to 8×10(-5) at 7 GeV/c(2).

9.
Phys Rev Lett ; 107(4): 041804, 2011 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-21866995

RESUMO

We report the observation of the decay B- → D(s)((*)+) K- ℓ- ν(ℓ) based on 342 fb(-1) of data collected at the Υ(4S) resonance with the BABAR detector at the PEP-II e+ e- storage rings at SLAC. A simultaneous fit to three D(s)(+) decay chains is performed to extract the signal yield from measurements of the squared missing mass in the B meson decay. We observe the decay B- → D(s)((*)+) K- ℓ- ν(ℓ) with a significance greater than 5 standard deviations (including systematic uncertainties) and measure its branching fraction to be B(B- → D(s)((*)+) K- ℓ- ν(ℓ)) = [6.13(-1.03)(+1.04)(stat)±0.43(syst)±0.51(B(D(s)))]×10(-4), where the last error reflects the limited knowledge of the D(s) branching fractions.

10.
Phys Rev Lett ; 107(2): 021804, 2011 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-21797597

RESUMO

We search for single-photon decays of the Υ(1S) resonance, Υ â†’ γ + invisible, where the invisible state is either a particle of definite mass, such as a light Higgs boson A°, or a pair of dark matter particles, χχ. Both A° and χ are assumed to have zero spin. We tag Υ(1S) decays with a dipion transition Υ(2S) → π⁺π⁻Υ(1S) and look for events with a single energetic photon and significant missing energy. We find no evidence for such processes in the mass range m(A°) ≤ 9.2 GeV and m(χ) ≤ 4.5 GeV in the sample of 98 × 106 Υ(2S) decays collected with the BABAR detector and set stringent limits on new physics models that contain light dark matter states.

11.
Phys Rev Lett ; 104(19): 191801, 2010 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-20866959

RESUMO

The ratio R(τµ)(Υ(1S))=Γ(Υ(1S)→τ+ τ-)/Γ(Υ(1S)→µ+ µ-) is measured using a sample of (121.8±1.2)×10(6)Υ(3S) events recorded by the BABAR detector. This measurement is intended as a test of lepton universality and as a search for a possible light pseudoscalar Higgs boson. In the standard model (SM) this ratio is expected to be close to 1. Any significant deviations would violate lepton universality and could be introduced by the coupling to a light pseudoscalar Higgs boson. The analysis studies the decays Υ(3S)→Υ(1S)π+ π-, Υ(1S)→l+ l-, where l=µ, τ. The result, R(τµ)(Υ(1S))=1.005±0.013(stat)±0.022(syst), shows no deviation from the expected SM value, while improving the precision with respect to previous measurements.

12.
Phys Rev Lett ; 105(12): 121801, 2010 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-20867628

RESUMO

We report the measurement of the Cabibbo-Kobayashi-Maskawa CP-violating angle γ through a Dalitz plot analysis of neutral D-meson decays to K(S)(0) π+ π- and K(S)(0) K+ K- produced in the processes B∓ → DK∓, B∓ D* K∓ with D* → Dπ(0), Dγ, and B∓ → DK*∓ with K*∓ → K(S)(0) π∓, using 468 million BB pairs collected by the BABAR detector at the PEP-II asymmetric-energy e+ e- collider at SLAC. We measure γ = (68 ± 14 ± 4 ± 3)° (modulo 180°), where the first error is statistical, the second is the experimental systematic uncertainty, and the third reflects the uncertainty in the description of the neutral D decay amplitudes. This result is inconsistent with γ = 0 (no direct CP violation) with a significance of 3.5 standard deviations.

13.
Phys Rev Lett ; 105(8): 081803, 2010 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-20868092

RESUMO

We report a direct measurement of D0-D0 mixing parameters through a time-dependent amplitude analysis of the Dalitz plots of D(0) → K(S)(0) π+ π- and, for the first time, D0 → K(S)(0)K+ K- decays. The low-momentum pion π(s)(+) in the decay D*+ → D0 π(s)(+) identifies the flavor of the neutral D meson at its production. Using 468.5 fb(-1) of e+ e- colliding-beam data recorded near square root(s)=10.6 GeV by the BABAR detector at the PEP-II asymmetric-energy collider at SLAC, we measure the mixing parameters x = [1.6 ± 2.3(stat) ± 1.2(syst) ± 0.8(model)] × 10(-3), and y = [5.7 ± 2.0(stat) ± 1.3(syst) ± 0.7(model)] × 10(-3). These results provide the best measurement to date of x and y. The knowledge of the value of x, in particular, is crucial for understanding the origin of mixing.

14.
Phys Rev Lett ; 104(15): 151802, 2010 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-20481982

RESUMO

Charged-lepton flavor-violating processes are unobservable in the standard model, but they are predicted to be enhanced in several extensions to the standard model, including supersymmetry and models with leptoquarks or compositeness. We present a search for such processes in a sample of 99x10(6)Upsilon(2S) decays and 117x10(6)Upsilon(3S) decays collected with the BABAR detector. We place upper limits on the branching fractions B(Upsilon(nS)-->e(+/-)tau(-/+)) and B(Upsilon(nS)-->mu(+/-)tau(-/+)) (n=2,3) at the 10(-6) level and use these results to place lower limits of order 1 TeV on the mass scale of charged-lepton flavor-violating effective operators.

15.
Phys Rev Lett ; 105(17): 172001, 2010 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-21231035

RESUMO

We present a search for f(J)(2220) production in radiative J/ψ→γf(J)(2220) decays using 460 fb⁻¹ of data collected with the BABAR detector at the SLAC PEP-II e(+)e⁻ collider. The f(J)(2220) is searched for in the decays to K(+)K⁻ and K(S)°K(S)°. No evidence of this resonance is observed, and 90% confidence level upper limits on the product of the branching fractions for J/ψ→γf(J)(2220) and f(J)(2220)→K(+)K⁻(K(S)°K(S)°) as a function of spin and helicity are set at the level of 10⁻5, below the central values reported by the Mark III experiment.

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