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3.
Stomatologiia (Mosk) ; 99(3): 74-77, 2020.
Artículo en Ruso | MEDLINE | ID: mdl-32608954

RESUMEN

AIM: To evaluate the actual nutrition of children receiving orthodontic treatment with bracket systems, to develop recommendations for its correction. Nutrition composition was assessed using a software analyzing the frequency of food consumption. Two groups of children were distinguished: the main group (without dentoalveolar anomalies) and the comparison group (with bracket systems). The total sample size was 58 adolescents. It was found that in schoolchildren receiving orthodontic treatment the imbalance in the intake of macro- and micronutrients with diets is much higher than in schoolchildren of the main group. In the daily diet of the main group of children, adequate adequate energy value was noted (94.6% of the physiological requirements), in contrast to schoolchildren in the comparison group (76.7%). Diets in children of the main group are deficient in the content of total protein (90.1%) and carbohydrates (86.4%), and excess in fats (112.2%). In the comparison group, the intake of macronutrients with food averaged 77.7% of the norm. The limited use of certain foods in children with bracket systems has led to a significant deficit in diets of meat (70.0% of the recommended level of consumption), fish and seafood (37.6%), eggs (55.0%), bakery products (44.9%), potatoes (78.7%), vegetables (66.0%), fruits (51.6%). The installation of bracket systems for orthodontic treatment is necessary to eliminate dentoalveolar anomalies in children, but it becomes both a risk factor for the formation of nutritional disorders in patients and a risk factor for tooth enamel demineralization. Therefore, it is necessary to develop recommendations for correcting the nutrition of children during the period of orthodontic treatment.


Asunto(s)
Ingestión de Energía , Estado Nutricional , Adolescente , Niño , Humanos , Aparatos Ortodóncicos Fijos , Verduras
4.
Phys Rev Lett ; 125(26): 262301, 2020 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-33449792

RESUMEN

Flow coefficients v_{n} of the orders n=1-6 are measured with the High-Acceptance DiElectron Spectrometer (HADES) at GSI for protons, deuterons, and tritons as a function of centrality, transverse momentum, and rapidity in Au+Au collisions at sqrt[s_{NN}]=2.4 GeV. Combining the information from the flow coefficients of all orders allows us to construct for the first time, at collision energies of a few GeV, a multidifferential picture of the angular emission pattern of these particles. It reflects the complicated interplay between the effect of the central fireball pressure on the emission of particles and their subsequent interaction with spectator matter. The high precision information on higher order flow coefficients is a major step forward in constraining the equation of state of dense baryonic matter.

5.
Phys Rev Lett ; 123(2): 022002, 2019 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-31386541

RESUMEN

We present the first observation of K^{-} and ϕ absorption within nuclear matter by means of π^{-}-induced reactions on C and W targets at an incident beam momentum of 1.7 GeV/c studied with HADES at SIS18/GSI. The double ratio (K^{-}/K^{+})_{W}/(K^{-}/K^{+})_{C} is found to be 0.319±0.009(stat)_{-0.012}^{+0.014}(syst) indicating a larger absorption of K^{-} in heavier targets as compared to lighter ones. The measured ϕ/K^{-} ratios in π^{-}+C and π^{-}+W reactions within the HADES acceptance are found to be equal to 0.55±0.04(stat)_{-0.07}^{+0.06}(syst) and to 0.63±0.06(stat)_{-0.11}^{+0.11}(syst), respectively. The similar ratios measured in the two different reactions demonstrate for the first time experimentally that the dynamics of the ϕ meson in nuclear medium is strongly coupled to the K^{-} dynamics. The large difference in the ϕ production off C and W nuclei is discussed in terms of a strong ϕN in-medium coupling. These results are relevant for the description of heavy-ion collisions and the structure of neutron stars.

6.
Vestn Khir Im I I Grek ; 175(2): 73-6, 2016.
Artículo en Inglés, Ruso | MEDLINE | ID: mdl-30427152

RESUMEN

This work aimed to reveal the statistically reliable clinical and laboratory markers, which are associated with fatal outcomes in patients with hemorrhagic shock of the III degree on the stage of hospital treatment. It was stated that decrease of body temperature (till 35,9 °C), pH of venous blood (till 7,19) and content of ionized calcium (till 0,32 mmole/l) in venous blood and increase of lactate content (up to 4,1 mmole/l) in venous blood and rise of activated partial thromboplastin time (up to 59 sec) are connected with fatal outcomes.


Asunto(s)
Sustitutos Sanguíneos/administración & dosificación , Hemorragia Gastrointestinal , Úlcera Péptica Hemorrágica , Choque Hemorrágico , Adulto , Temperatura Corporal , Calcio/análisis , Femenino , Hemorragia Gastrointestinal/complicaciones , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/terapia , Humanos , Concentración de Iones de Hidrógeno , Masculino , Gravedad del Paciente , Úlcera Péptica Hemorrágica/complicaciones , Úlcera Péptica Hemorrágica/diagnóstico , Úlcera Péptica Hemorrágica/terapia , Valor Predictivo de las Pruebas , Choque Hemorrágico/diagnóstico , Choque Hemorrágico/etiología , Choque Hemorrágico/mortalidad , Choque Hemorrágico/prevención & control , Resultado del Tratamiento
7.
Phys Rev Lett ; 114(21): 212301, 2015 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-26066429

RESUMEN

Results on the production of the double strange cascade hyperon Ξ^{-} are reported for collisions of p(3.5 GeV)+Nb, studied with the High Acceptance Di-Electron Spectrometer (HADES) at SIS18 at GSI Helmholtzzentrum for Heavy-Ion Research, Darmstadt. For the first time, subthreshold Ξ^{-} production is observed in proton-nucleus interactions. Assuming a Ξ^{-} phase-space distribution similar to that of Λ hyperons, the production probability amounts to P_{Ξ^{-}}=[2.0±0.4(stat)±0.3(norm)±0.6(syst)]×10^{-4} resulting in a Ξ^{-}/(Λ+Σ^{0}) ratio of P_{Ξ^{-}}/P_{Λ+Σ^{0}}=[1.2±0.3(stat)±0.4(syst)]×10^{-2}. Available model predictions are significantly lower than the measured Ξ^{-} yield.

8.
Phys Rev Lett ; 108(22): 222004, 2012 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23180491

RESUMEN

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.

9.
Phys Rev Lett ; 106(13): 132501, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21520982

RESUMEN

Intensive theoretical and experimental efforts over the past decade have aimed at explaining the discrepancy between data for the proton electric to magnetic form factor ratio, G(E)/G(M), obtained separately from cross section and polarization transfer measurements. One possible explanation for this difference is a two-photon-exchange contribution. In an effort to search for effects beyond the one-photon-exchange or Born approximation, we report measurements of polarization transfer observables in the elastic H(e[over →],e(')p[over →]) reaction for three different beam energies at a Q(2)=2.5 GeV(2), spanning a wide range of the kinematic parameter ε. The ratio R, which equals µ(p)G(E)/G(M) in the Born approximation, is found to be independent of ε at the 1.5% level. The ε dependence of the longitudinal polarization transfer component P(ℓ) shows an enhancement of (2.3±0.6)% relative to the Born approximation at large ε.

10.
Phys Rev Lett ; 104(24): 242301, 2010 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-20873943

RESUMEN

Among the most fundamental observables of nucleon structure, electromagnetic form factors are a crucial benchmark for modern calculations describing the strong interaction dynamics of the nucleon's quark constituents; indeed, recent proton data have attracted intense theoretical interest. In this Letter, we report new measurements of the proton electromagnetic form factor ratio using the recoil polarization method, at momentum transfers Q2=5.2, 6.7, and 8.5 GeV2. By extending the range of Q2 for which G(E)(p) is accurately determined by more than 50%, these measurements will provide significant constraints on models of nucleon structure in the nonperturbative regime.

11.
Gig Sanit ; (5): 65-9, 2009.
Artículo en Ruso | MEDLINE | ID: mdl-20000093

RESUMEN

A complex of chemical, physical, and biological factors of varying intensity influences man under the dwelling environmental conditions. Modern man spends as high as 80-90% of the day time under the conditions of the closed spaces of the urbanized habitat and is constantly exposed to physical factors. The present environmental hygiene monitoring system requires great attention to the control of priority physical factors in the environment. By using a number of examples, the authors give criteria for determining the priority of factors of physical nature and an objective assessment of their importance in the formation of the safe dwelling environment.


Asunto(s)
Exposición a Riesgos Ambientales/efectos adversos , Salud Ambiental/métodos , Enfermedades Ambientales/epidemiología , Higiene/normas , Medición de Riesgo/métodos , Población Urbana , Humanos , Morbilidad/tendencias , Federación de Rusia/epidemiología
12.
Phys Rev Lett ; 103(13): 132301, 2009 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-19905504

RESUMEN

We report first results on a deep subthreshold production of the doubly strange hyperon Xi;{-} in a heavy-ion reaction. At a beam energy of 1.76A GeV the reaction Ar + KCl was studied with the High Acceptance Di-Electron Spectrometer at SIS18/GSI. A high-statistics and high-purity Lambda sample was collected, allowing for the investigation of the decay channel Xi;{-} --> Lambdapi;{-}. The deduced Xi;{-}/(Lambda + Sigma;{0}) production ratio of (5.6 +/- 1.2_{-1.7};{+1.8}) x 10;{-3} is significantly larger than available model predictions.

13.
Am J Transplant ; 9(5): 1214-22, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19422346

RESUMEN

Late-onset cytomegalovirus (CMV) disease commonly occurs after discontinuation of antiviral prophylaxis. We determined the utility of testing CD8+ T-cell response against CMV as a predictor of late-onset CMV disease after a standard course of antiviral prophylaxis. Transplant patients at high-risk for CMV disease were enrolled. CD8+ T-cell-mediated immunity (CMI) was tested using the QuantiFERON-CMV assay at baseline, 1, 2 and 3 months posttransplant by measurement of interferon-gamma response to whole blood stimulation with a 21-peptide pool. The primary outcome was the ability of CMI testing to predict CMV disease in the first 6 months posttransplant. There were 108 evaluable patients (D+/R+ n = 39; D-/R+ n = 34; D+/R- n = 35) of whom 18 (16.7%) developed symptomatic CMV disease. At the end of prophylaxis, CMI was detectable in 38/108 (35.2%) patients (cutoff 0.1 IU/mL interferon-gamma). CMV disease occurred in 2/38 (5.3%) patients with a detectable interferon-gamma response versus 16/70 (22.9%) patients with a negative response; p = 0.038. In the subgroup of D+/R- patients, CMV disease occurred in 1/10 (10.0%) patients with a detectable interferon-gamma response (cutoff 0.1 IU/mL) versus 10/25 (40.0%) patients with a negative CMI, p = 0.12. Monitoring of CMI may be useful for predicting late-onset CMV disease.


Asunto(s)
Infecciones por Citomegalovirus/epidemiología , Infecciones por Citomegalovirus/inmunología , Inmunidad Celular , Inmunología del Trasplante , Suero Antilinfocítico/uso terapéutico , Antivirales/uso terapéutico , Linfocitos T CD8-positivos/inmunología , Infecciones por Citomegalovirus/tratamiento farmacológico , Estudios de Seguimiento , Humanos , Inmunidad Celular/efectos de los fármacos , Inmunosupresores/uso terapéutico , Interferón gamma/inmunología , Trasplante de Riñón/inmunología , Trasplante de Hígado/inmunología , Trasplante de Pulmón/inmunología , Trasplante de Páncreas/inmunología , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Factores de Riesgo
14.
Am J Transplant ; 7(11): 2567-72, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17908277

RESUMEN

The immunogenicity of influenza vaccine is suboptimal in lung transplant recipients. Use of a booster dose and vaccine delivery by the intradermal rather than intramuscular route may improve response. We prospectively evaluated the immunogenicity and safety of a 2-dose boosting strategy of influenza vaccine. Sixty lung transplant recipients received a standard intramuscular injection of the 2006-2007 inactivated influenza vaccine, followed 4 weeks later by an intradermal booster of the same vaccine. Immunogenicity was assessed by measurement of geometric mean titer of antibodies after both the intramuscular injection and the intradermal booster. Vaccine response was defined as 4-fold or higher increase of antibody titers to at least one vaccine antigen. Thirty-eight out of 60 patients (63%) had a response after intramuscular vaccination. Geometric mean titers increased for all three vaccine antigens following the first dose (p < 0.001). However, no significant increases in titer were observed after the booster dose for all three antigens. Among nonresponders, 3/22 (13.6%) additional patients responded after the intradermal booster (p = 0.14). The use of basiliximab was associated with a positive response (p = 0.024). After a single standard dose of influenza vaccine, a booster dose given by intradermal injection did not significantly improve vaccine immunogenicity in lung transplant recipients.


Asunto(s)
Vacunas contra la Influenza/administración & dosificación , Trasplante de Pulmón/inmunología , Vacunación/estadística & datos numéricos , Vacunas de Productos Inactivados/administración & dosificación , Adulto , Anciano , Anticuerpos Antivirales/sangre , Femenino , Humanos , Inmunización Secundaria , Inyecciones Intradérmicas , Inyecciones Intramusculares , Masculino , Persona de Mediana Edad , Seguridad , Vacunación/normas
15.
Phys Rev Lett ; 98(5): 052302, 2007 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-17358850

RESUMEN

The invariant-mass spectrum of e+e- pairs produced in 12C+12C collisions at an incident energy of 2 GeV per nucleon has been measured for the first time. The measured pair production probabilities span over 5 orders of magnitude from the pi(0)-Dalitz to the rho/omega invariant-mass region. Dalitz decays of pi(0) and eta account for all the yield up to 0.15 GeV/c(2), but for only about 50% above this mass. A comparison with model calculations shows that the excess pair yield is likely due to baryon-resonance and vector-meson decays. Transport calculations based on vacuum spectral functions fail, however, to describe the entire mass region.

16.
Phys Rev Lett ; 95(15): 152301, 2005 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-16241721

RESUMEN

Charged hadrons in [EQUATION: SEE TEXT] associated with particles of [EQUATION: SEE TEXT] are reconstructed in pp and Au+Au collisions at sqrt[sNN]=200 GeV. The associated multiplicity and p magnitude sum are found to increase from pp to central Au+Au collisions. The associated p distributions, while similar in shape on the nearside, are significantly softened on the awayside in central Au+Au relative to pp and not much harder than that of inclusive hadrons. The results, consistent with jet quenching, suggest that the awayside fragments approach equilibration with the medium traversed.

17.
Phys Rev Lett ; 92(17): 171801, 2004 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-15169138

RESUMEN

Measurements of the production of forward high-energy pi(0) mesons from transversely polarized proton collisions at sqrt[s]=200 GeV are reported. The cross section is generally consistent with next-to-leading order perturbative QCD calculations. The analyzing power is small at x(F) below about 0.3, and becomes positive and large at higher x(F), similar to the trend in data at sqrt[s]< or =20 GeV. The analyzing power is in qualitative agreement with perturbative QCD model expectations. This is the first significant spin result seen for particles produced with p(T)>1 GeV/c at a polarized proton collider.

18.
Phys Rev Lett ; 92(11): 112301, 2004 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-15089125

RESUMEN

Transverse mass and rapidity distributions for charged pions, charged kaons, protons, and antiprotons are reported for square root of [sNN]=200 GeV pp and Au+Au collisions at Relativistic Heary Ion Collider (RHIC). Chemical and kinetic equilibrium model fits to our data reveal strong radial flow and long duration from chemical to kinetic freeze-out in central Au+Au collisions. The chemical freeze-out temperature appears to be independent of initial conditions at RHIC energies.

19.
Phys Rev Lett ; 92(9): 092301, 2004 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-15089460

RESUMEN

We report results on rho(770)(0)-->pi(+)pi(-) production at midrapidity in p+p and peripheral Au+Au collisions at sqrt[s(NN)]=200 GeV. This is the first direct measurement of rho(770)(0)-->pi(+)pi(-) in heavy-ion collisions. The measured rho(0) peak in the invariant mass distribution is shifted by approximately 40 MeV/c(2) in minimum bias p+p interactions and approximately 70 MeV/c(2) in peripheral Au+Au collisions. The rho(0) mass shift is dependent on transverse momentum and multiplicity. The modification of the rho(0) meson mass, width, and shape due to phase space and dynamical effects are discussed.

20.
Phys Rev Lett ; 92(6): 062301, 2004 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-14995231

RESUMEN

We report the first observations of the first harmonic (directed flow, v(1)) and the fourth harmonic (v(4)), in the azimuthal distribution of particles with respect to the reaction plane in Au+Au collisions at the BNL Relativistic Heavy Ion Collider (RHIC). Both measurements were done taking advantage of the large elliptic flow (v(2)) generated at RHIC. From the correlation of v(2) with v(1) it is determined that v(2) is positive, or in-plane. The integrated v(4) is about a factor of 10 smaller than v(2). For the sixth (v(6)) and eighth (v(8)) harmonics upper limits on the magnitudes are reported.

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