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1.
BMC Public Health ; 22(1): 2153, 2022 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-36419146

RESUMEN

BACKGROUND: Tuberculosis (TB) has been repeatedly shown to have socioeconomic impacts in both individual-level and ecological studies; however, much less is known about this effect among children and adolescents and the extent to which being affected by TB during childhood and adolescence can have life-course implications. This paper describes the results of the development of a conceptual framework and scoping review to review the evidence on the short- and long-term socioeconomic impact of tuberculosis on children and adolescents. OBJECTIVES: To increase knowledge of the socioeconomic impact of TB on children and adolescents. METHODS: We developed a conceptual framework of the socioeconomic impact of TB on children and adolescents, and used scoping review methods to search for evidence supporting or disproving it. We searched four academic databases from 1 January 1990 to 6 April 2021 and conducted targeted searches of grey literature. We extracted data using a standard form and analysed data thematically. RESULTS: Thirty-six studies (29 qualitative, five quantitative and two mixed methods studies) were included in the review. Overall, the evidence supported the conceptual framework, suggesting a severe socioeconomic impact of TB on children and adolescents through all the postulated pathways. Effects ranged from impoverishment, stigma, and family separation, to effects on nutrition and missed education opportunities. TB did not seem to exert a different socioeconomic impact when directly or indirectly affecting children/adolescents, suggesting that TB can affect this group even when they are not affected by the disease. No study provided sufficient follow-up to observe the long-term socioeconomic effect of TB in this age group. CONCLUSION: The evidence gathered in this review reinforces our understanding of the impact of TB on children and adolescents and highlights the importance of considering effects during the entire life course. Both ad-hoc and sustainable social protection measures and strategies are essential to mitigate the socioeconomic consequences of TB among children and adolescents.


Asunto(s)
Tuberculosis , Niño , Humanos , Adolescente , Tuberculosis/epidemiología , Estigma Social , Bases de Datos Factuales , Escolaridad , Conocimiento
2.
Phys Rev Lett ; 127(6): 062003, 2021 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-34420329

RESUMEN

We describe an analysis comparing the pp[over ¯] elastic cross section as measured by the D0 Collaboration at a center-of-mass energy of 1.96 TeV to that in pp collisions as measured by the TOTEM Collaboration at 2.76, 7, 8, and 13 TeV using a model-independent approach. The TOTEM cross sections, extrapolated to a center-of-mass energy of sqrt[s]=1.96 TeV, are compared with the D0 measurement in the region of the diffractive minimum and the second maximum of the pp cross section. The two data sets disagree at the 3.4σ level and thus provide evidence for the t-channel exchange of a colorless, C-odd gluonic compound, also known as the odderon. We combine these results with a TOTEM analysis of the same C-odd exchange based on the total cross section and the ratio of the real to imaginary parts of the forward elastic strong interaction scattering amplitude in pp scattering for which the significance is between 3.4σ and 4.6σ. The combined significance is larger than 5σ and is interpreted as the first observation of the exchange of a colorless, C-odd gluonic compound.

3.
Phys Rev Lett ; 120(24): 241802, 2018 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-29956986

RESUMEN

We present a measurement of the effective weak mixing angle parameter sin^{2}θ_{eff}^{ℓ} in pp[over ¯]→Z/γ^{*}→µ^{+}µ^{-} events at a center-of-mass energy of 1.96 TeV, collected by the D0 detector at the Fermilab Tevatron Collider and corresponding to 8.6 fb^{-1} of integrated luminosity. The measured value of sin^{2}θ_{eff}^{ℓ}[µµ]=0.23016±0.00064 is further combined with the result from the D0 measurement in pp[over ¯]→Z/γ^{*}→e^{+}e^{-} events, resulting in sin^{2}θ_{eff}^{ℓ}[comb]=0.23095±0.00040. This combined result is the most precise measurement from a single experiment at a hadron collider and is the most precise determination using the coupling of the Z/γ^{*} to light quarks.

4.
Phys Rev Lett ; 120(4): 042001, 2018 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-29437406

RESUMEN

The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of sqrt[s]=1.96 TeV. We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is A_{FB}^{tt[over ¯]}=0.128±0.025. The combined inclusive and differential asymmetries are consistent with recent standard model predictions.

5.
Phys Rev Lett ; 117(2): 022003, 2016 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-27447502

RESUMEN

We report evidence for a narrow structure, X(5568), in the decay sequence X(5568)→B_{s}^{0}π^{±}, B_{s}^{0}→J/ψϕ, J/ψ→µ^{+}µ^{-}, ϕ→K^{+}K^{-}. This is evidence for the first instance of a hadronic state with valence quarks of four different flavors. The mass and natural width of this state are measured to be m=5567.8±2.9(stat)_{-1.9}^{+0.9}(syst) MeV/c^{2} and Γ=21.9±6.4(stat)_{-2.5}^{+5.0}(syst) MeV/c^{2}. If the decay is X(5568)→B_{s}^{*}π^{±}→B_{s}^{0}γπ^{±} with an unseen γ, m(X(5568)) will be shifted up by m(B_{s}^{*})-m(B_{s}^{0})∼49 MeV/c^{2}. This measurement is based on 10.4 fb^{-1} of pp[over ¯] collision data at sqrt[s]=1.96 TeV collected by the D0 experiment at the Fermilab Tevatron collider.

6.
Phys Rev Lett ; 116(8): 082002, 2016 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-26967412

RESUMEN

We report evidence for the simultaneous production of J/ψ and ϒ mesons in 8.1 fb^{-1} of data collected at sqrt[s]=1.96 TeV by the D0 experiment at the Fermilab pp[over ¯] Tevatron Collider. Events with these characteristics are expected to be produced predominantly by gluon-gluon interactions. In this analysis, we extract the effective cross section characterizing the initial parton spatial distribution, σ_{eff}=2.2±0.7(stat)±0.9(syst) mb.

7.
Phys Rev Lett ; 115(23): 232001, 2015 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-26684112

RESUMEN

We present a study of the inclusive production of the X(4140) state with the decay to the J/ψϕ final state in hadronic collisions. Based on 10.4 fb^{-1} of pp[over ¯] collision data collected by the D0 experiment at the Fermilab Tevatron collider, we report the first evidence for the prompt production of an X(4140) state and find the fraction of X(4140) events originating from b hadrons to be f_{b}=0.39±0.07(stat)±0.10(syst). The ratio of the nonprompt X(4140) production rate to the B_{s}^{0} yield in the same channel is R=0.19±0.05(stat)±0.07(syst). The values of the mass M=4152.5±1.7(stat)_{-5.4}^{+6.2}(syst) MeV and width Γ=16.3±5.6(stat)±11.4(syst) MeV are consistent with previous measurements.

8.
Phys Rev Lett ; 114(5): 051803, 2015 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-25699435

RESUMEN

We present a measurement of the forward-backward asymmetry in the production of B(±) mesons, A(FB)(B(±)), using B(±)→J/ψK(±) decays in 10.4 fb(-1) of pp̄ collisions at sqrt[s]=1.96 TeV collected by the D0 experiment during Run II of the Tevatron collider. A nonzero asymmetry would indicate a preference for a particular flavor, i.e., b quark or ̄b antiquark, to be produced in the direction of the proton beam. We extract A(FB)(B(±)) from a maximum likelihood fit to the difference between the numbers of forward- and backward-produced B(±) mesons. We measure an asymmetry consistent with zero: A(FB)(B(±))=[-0.24±0.41 (stat)±0.19 (syst)]%.

9.
Phys Rev Lett ; 114(6): 062001, 2015 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-25723207

RESUMEN

We present an updated measurement of the B(s)(0) lifetime using the semileptonic decays B(s)(0)→D(s)(-)µ(+)νX, with D(s)(-)→ϕπ(-) and ϕ→K(+)K(-) (and the charge conjugate process). This measurement uses the full Tevatron Run II sample of proton-antiproton collisions at √[s]=1.96 TeV, comprising an integrated luminosity of 10.4 fb(-1). We find a flavor-specific lifetime τ(fs)(B(s)(0))=1.479±0.010(stat)±0.021(syst) ps. This technique is also used to determine the B(0) lifetime using the analogous B(0)→D(-)µ(+)νX decay with D(-)→ϕπ(-) and ϕ→K(+)K(-), yielding τ(B(0))=1.534±0.019(stat)±0.021(syst) ps. Both measurements are consistent with the current world averages, and the B(s)(0) lifetime measurement is one of the most precise to date. Taking advantage of the cancellation of systematic uncertainties, we determine the lifetime ratio τ(fs)(B(s)(0))/τ(B(0))=0.964±0.013(stat)±0.007(syst).

10.
Phys Rev Lett ; 115(15): 152003, 2015 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-26550718

RESUMEN

We present the final combination of CDF and D0 measurements of cross sections for single-top-quark production in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV. The data correspond to total integrated luminosities of up to 9.7 fb^{-1} per experiment. The t-channel cross section is measured to be σ_{t}=2.25_{-0.31}^{+0.29} pb. We also present the combinations of the two-dimensional measurements of the s- vs t-channel cross section. In addition, we give the combination of the s+t channel cross section measurement resulting in σ_{s+t}=3.30_{-0.40}^{+0.52} pb, without assuming the standard model value for the ratio σ_{s}/σ_{t}. The resulting value of the magnitude of the top-to-bottom quark coupling is |V_{tb}|=1.02_{-0.05}^{+0.06}, corresponding to |V_{tb}|>0.92 at the 95% C.L.

11.
Phys Rev Lett ; 115(16): 161601, 2015 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-26550864

RESUMEN

We present the first search for CPT-violating effects in the mixing of Bs(0) mesons using the full Run II data set with an integrated luminosity of 10.4 fb(-1) of proton-antiproton collisions collected using the D0 detector at the Fermilab Tevatron Collider. We measure the CPT-violating asymmetry in the decay Bs(0)→µ(±)Ds(±) as a function of celestial direction and sidereal phase. We find no evidence for CPT-violating effects and place limits on the direction and magnitude of flavor-dependent CPT- and Lorentz-invariance violating coupling coefficients. We find 95% confidence intervals of Δa⊥<1.2×10(-12) GeV and (-0.8<ΔaT-0.396ΔaZ<3.9)×10(-13) GeV.

12.
Phys Rev Lett ; 114(15): 151802, 2015 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-25933309

RESUMEN

Combined constraints from the CDF and D0 Collaborations on models of the Higgs boson with exotic spin J and parity P are presented and compared with results obtained assuming the standard model value JP=0+. Both collaborations analyzed approximately 10 fb(-) of proton-antiproton collisions with a center-of-mass energy of 1.96 TeV collected at the Fermilab Tevatron. Two models predicting exotic Higgs bosons with JP=0- and JP=2+ are tested. The kinematic properties of exotic Higgs boson production in association with a vector boson differ from those predicted for the standard model Higgs boson. Upper limits at the 95% credibility level on the production rates of the exotic Higgs bosons, expressed as fractions of the standard model Higgs boson production rate, are set at 0.36 for both the JP=0- hypothesis and the JP=2+ hypothesis. If the production rate times the branching ratio to a bottom-antibottom pair is the same as that predicted for the standard model Higgs boson, then the exotic bosons are excluded with significances of 5.0 standard deviations and 4.9 standard deviations for the JP=0- and JP=2+ hypotheses, respectively.

13.
Phys Rev Lett ; 115(4): 041801, 2015 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-26252676

RESUMEN

We present a measurement of the fundamental parameter of the standard model, the weak mixing angle sin^{2}θ_{eff}^{ℓ} which determines the relative strength of weak and electromagnetic interactions, in pp[over ¯]→Z/γ^{*}→e^{+}e^{-} events at a center of mass energy of 1.96 TeV, using data corresponding to 9.7 fb^{-1} of integrated luminosity collected by the D0 detector at the Fermilab Tevatron. The effective weak mixing angle is extracted from the forward-backward charge asymmetry as a function of the invariant mass around the Z boson pole. The measured value of sin^{2}θ_{eff}^{ℓ}=0.23147±0.00047 is the most precise measurement from light quark interactions to date, with a precision close to the best LEP and SLD results.

14.
J R Army Med Corps ; 161(2): 140-3, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25428136

RESUMEN

Military recruits are known to be susceptible to Achilles tendon pathology. The British Army have introduced footwear models, the PT-03 (cross-trainer) and PT1000 (running shoes), in an attempt to reduce the incidence of injuries. The aim of the current investigation was to examine the Achilles tendon forces of the cross-trainer and running shoe in relation to conventional army boots. Ten male participants ran at 4.0 m/s in each footwear condition. Achilles tendon forces were obtained throughout the stance phase of running and compared using repeated-measures ANOVAs. The results showed that the time to peak Achilles tendon force was significantly shorter when running in conventional army boots (0.12 s) in comparison with the cross-trainer (0.13 s) and running shoe (0.13 s). Achilles tendon loading rate was shown to be significantly greater in conventional army boots (38.73 BW/s) in comparison with the cross-trainer (35.14 BW/s) and running shoe (33.57 BW/s). The results of this study suggest that the running shoes and cross-trainer footwear are associated with reductions in Achilles tendon parameters that have been linked to the aetiology of injury, and thus it can be hypothesised that these footwear could be beneficial for military recruits undertaking running exercises.


Asunto(s)
Tendón Calcáneo/fisiología , Carrera/fisiología , Zapatos , Adulto , Fenómenos Biomecánicos , Humanos , Masculino , Personal Militar , Adulto Joven
15.
Phys Rev Lett ; 113(16): 161802, 2014 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-25361251

RESUMEN

We present constraints on models containing non-standard-model values for the spin J and parity P of the Higgs boson H in up to 9.7 fb(-1) of pp collisions at sqrt[s] = 1.96 TeV collected with the D0 detector at the Fermilab Tevatron Collider. These are the first studies of Higgs boson J(P) with fermions in the final state. In the ZH → ℓℓbb, WH → ℓνbb, and ZH → ννbb final states, we compare the standard model (SM) Higgs boson prediction, J(P) = 0(+), with two alternative hypotheses, J(P) = 0(-) and J(P) = 2(+). We use a likelihood ratio to quantify the degree to which our data are incompatible with non-SM J(P) predictions for a range of possible production rates. Assuming that the production rate in the signal models considered is equal to the SM prediction, we reject the J(P) = 0(-) and J(P) = 2(+) hypotheses at the 97.6% CL and at the 99.0% CL, respectively. The expected exclusion sensitivity for a J(P) = 0(-) (J(P) = 2(+)) state is at the 99.86% (99.94%) CL. Under the hypothesis that our data are the result of a combination of the SM-like Higgs boson and either a J(P) = 0(-) or a J(P) = 2(+) signal, we exclude a J(P) = 0(-) fraction above 0.80 and a J(P) = 2(+) fraction above 0.67 at the 95% CL. The expected exclusion covers J(P) = 0(-) (J(P) = 2(+)) fractions above 0.54 (0.47).

16.
Phys Rev Lett ; 112(15): 151803, 2014 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-24785031

RESUMEN

We present a measurement of the W boson production charge asymmetry in pp̄→W+X→eν+X events at a center of mass energy of 1.96 TeV, using 9.7 fb-1 of integrated luminosity collected with the D0 detector at the Fermilab Tevatron Collider. The neutrino longitudinal momentum is determined by using a neutrino weighting method, and the asymmetry is measured as a function of the W boson rapidity. The measurement extends over wider electron pseudorapidity region than previous results and is the most precise to date, allowing for precise determination of proton parton distribution functions in global fits.

17.
Phys Rev Lett ; 113(3): 032002, 2014 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-25083634

RESUMEN

We measure the mass of the top quark in lepton+jets final states using the full sample of pp collision data collected by the D0 experiment in Run II of the Fermilab Tevatron Collider at sqrt[s] = 1.96 TeV, corresponding to 9.7 fb(-1) of integrated luminosity. We use a matrix element technique that calculates the probabilities for each event to result from tt production or background. The overall jet energy scale is constrained in situ by the mass of the W boson. We measure m(t) = 174.98 ± 0.76 GeV. This constitutes the most precise single measurement of the top-quark mass.

18.
Phys Rev Lett ; 112(11): 111804, 2014 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-24702352

RESUMEN

We present a measurement of the direct CP-violating charge asymmetry in Ds+ → ϕ π(±) decays where the ϕ meson decays to K(+)K(-), using the full Run II data set with an integrated luminosity of 10.4 fb-1 of proton-antiproton collisions collected using the D0 detector at the Fermilab Tevatron Collider. The normalized difference A(CP) in the yield of D(s)(+) and D(s)(-) mesons in these decays is measured by fitting the difference between their reconstructed invariant mass distributions. This results in an asymmetry of A(CP) = [-0.38 ± 0.27]%, which is the most precise measurement of this quantity to date. The result is consistent with the standard model prediction of zero CP asymmetry in this decay.

19.
Phys Rev Lett ; 112(4): 042001, 2014 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-24580440

RESUMEN

We present the first measurements of the ratios of cross sections σ(pp → Z+c jet)/σ(pp → Z+jet) and σ(pp → Z+c jet)/σ(pp → Z+b jet) for the associated production of a Z boson with at least one charm or bottom quark jet. Jets have transverse momentum ​pT(jet)​>20 GeV and pseudorapidity |​η(jet)​|<2.5. These cross section ratios are measured differentially as a function of jet and Z boson transverse momenta, based on 9.7 fb(-1) of pp collisions collected with the D0 detector at the Fermilab Tevatron Collider at √s=1.96 TeV. The measurements show significant deviations from perturbative QCD calculations and predictions from various event generators.

20.
Phys Rev Lett ; 112(23): 231803, 2014 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-24972197

RESUMEN

We report the first observation of single-top-quark production in the s channel through the combination of the CDF and D0 measurements of the cross section in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV. The data correspond to total integrated luminosities of up to 9.7 fb(-1) per experiment. The measured cross section is σ(s) = 1.29(-0.24)(+0.26) pb. The probability of observing a statistical fluctuation of the background to a cross section of the observed size or larger is 1.8 × 10(-10), corresponding to a significance of 6.3 standard deviations for the presence of an s-channel contribution to the production of single-top quarks.

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