| 1. |
- Aad, G, et al.
(author)
-
- 2015
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swepub:Mat__t
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| 2. |
- Aaltonen, T., et al.
(author)
-
Tevatron Run II combination of the effective leptonic electroweak mixing angle
- 2018
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In: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 97:11
-
Journal article (peer-reviewed)abstract
- Drell-Yan lepton pairs produced in the process p (p) over bar -> l(+)l(-) + X through an intermediate gamma*/Z boson have an asymmetry in their angular distribution related to the spontaneous symmetry breaking of the electroweak force and the associated mixing of its neutral gauge bosons. The CDF and D0 experiments have measured the effective-leptonic electroweak mixing parameter sin(2) theta(lept)(eff) using electron and muon pairs selected from the full Tevatron proton-antiproton data sets collected in 2001-2011, corresponding to 9-10 fb(-1) of integrated luminosity. The combination of these measurements yields the most precise result from hadron colliders, sin(2)theta(lept)(eff) = 0.23148 +/- 0.00033. This result is consistent with, and approaches in precision, the best measurements from electron-positron colliders. The standard model inference of the on-shell electroweak mixing parameter sin(2) theta(W), or equivalently the W-boson mass M-W, using the ZFITTER software package yields sin(2) theta(W) = 0.22324 +/- 0.00033 or equivalently, M-W = 80.367 +/- 0.017 GeV/c(2).
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| 3. |
- Aaltonen, T., et al.
(author)
-
Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron
- 2018
-
In: Physical Review Letters. - : AMER PHYSICAL SOC. - 0031-9007 .- 1079-7114. ; 120:4
-
Journal article (peer-reviewed)abstract
- 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 root 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)(t (t) over bar) = 0.128 +/- 0.025. The combined inclusive and differential asymmetries are consistent with recent standard model predictions.
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| 4. |
- Aaltonen, T., et al.
(author)
-
Tevatron Combination of Single-Top-Quark Cross Sections and Determination of the Magnitude of the Cabibbo-Kobayashi-Maskawa Matrix Element V-tb
- 2015
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 115:15
-
Journal article (peer-reviewed)abstract
- 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 sigma(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 sigma(s+t) = 3.30(-0.40)(+0.52) pb, without assuming the standard model value for the ratio sigma(s)/sigma(t). The resulting value of the magnitude of the top-to-bottom quark coupling is vertical bar V-tb vertical bar = 1.02(-0.05)(+0.06), corresponding to vertical bar V-tb vertical bar > 0.92 at the 95% C. L.
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| 5. |
- Aaltonen, T., et al.
(author)
-
Tevatron Constraints on Models of the Higgs Boson with Exotic Spin and Parity Using Decays to Bottom-Antibottom Quark Pairs
- 2015
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 114:15
-
Journal article (peer-reviewed)abstract
- 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 J(P) = 0(+). Both collaborations analyzed approximately 10 fb(-1) 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 J(P) = 0(-) and J(P) = 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 J(P) = 0(-) hypothesis and the J(P) = 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 J(P) = 0(-) and J(P) = 2(+) hypotheses, respectively.
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| 6. |
- Abazov, V. M., et al.
(author)
-
B-s(0) lifetime measurement in the CP-odd decay channel B-s(0) -> J/Psi f(0)(980)
- 2016
-
In: PHYSICAL REVIEW D. - 2470-0010. ; 94:1
-
Journal article (peer-reviewed)abstract
- The lifetime of the B-s(0) meson is measured in the decay channel B-s(0) -> J/Psi pi(+)pi(-) with 880 <= M pi+pi- <= 1080 MeV/c(2), which is mainly a CP-odd state and dominated by the f(0)(980) resonance. In 10.4 fb(-1) of data collected with the D0 detector in Run II of the Tevatron, the lifetime of the B-s(0) meson is measured to be tau(B-s(0)) = 1.70 +/- 0.14(stat) +/- 0.05(syst) ps. Neglecting CP violation in B-s(0)/(B) over bar (0)(s) mixing, the measurement can be translated into the width of the heavy mass eigenstate of the B-s(0), Gamma(H) = 0.59 +/- 0.05(stat) +/- 0.02(syst) ps(-1).
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| 7. |
- Abazov, V. M., et al.
(author)
-
Combination of D0 measurements of the top quark mass
- 2017
-
In: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 95:11
-
Journal article (peer-reviewed)abstract
- We present a combination of measurements of the top quark mass by the D0 experiment in the lepton + jets and dilepton channels. We use all the data collected in Run I (1992-1996) at root s = 1.8 TeV and Run II (2001-2011) at root s = 1.96 TeV of the Tevatron p (p) over bar collider, corresponding to integrated luminosities of 0.1 fb(-1) and 9.7 fb(-1), respectively. The combined result is: m(t) = 174.95 +/- 0.40(stat)+/- 0.64(syst) GeV = 174.95 +/- 0.75 GeV.
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| 8. |
- Abazov, V. M., et al.
(author)
-
Evidence for a B-s(0)pi(+/-) State
- 2016
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 117:2
-
Journal article (peer-reviewed)abstract
- We report evidence for a narrow structure, X(5568), in the decay sequence X(5568) -> B-s(0)pi(+/-), B-s(0) -> J/psi phi, J/psi -> mu(+)mu(-), phi -> 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 Gamma = 21.9 +/- 6.4(stat)(-2.5)(+5.0) (syst) MeV/c(2). If the decay is X(5568) -> B-s*pi(+/-). B-s(0)gamma pi(+/-) with an unseen gamma, m(X(5568)) will be shifted up by m(B-s*) - m(B-s(0)) similar to 49 MeV/c(2). This measurement is based on 10.4 fb(-1) of p (p) over bar collision data at root s = 1.96 TeV collected by the D0 experiment at the Fermilab Tevatron collider.
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| 9. |
- Abazov, V. M., et al.
(author)
-
Evidence for Simultaneous Production of J/psi and Upsilon Mesons
- 2016
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 116:8
-
Journal article (peer-reviewed)abstract
- We report evidence for the simultaneous production of J/psi and Upsilon mesons in 8.1 fb(-1) of data collected at root s = 1.96 TeV by the D0 experiment at the Fermilab p (p) over bar 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, sigma(eff) = 2.2 +/- 0.7(stat) +/- 0.9(syst) mb.
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| 10. |
- Abazov, V. M., et al.
(author)
-
Evidence for Z(c)(+/-)(3900) in semi-inclusive decays of b-flavored hadrons
- 2018
-
In: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 98:5
-
Journal article (peer-reviewed)abstract
- We present evidence for the exotic charged charmoniumlike state Z(c)(+/-)(3900) decaying to J/psi pi(+/-) in semi-inclusive weak decays of b-flavored hadrons. The signal is correlated with a parent J/psi pi(+)pi(-) system in the invariant-mass range 4.2-4.7 GeV that would include the exotic structure Y(4260). The study is based on 10.4 fb(-1) of p (p) over bar collision data collected by the D0 experiment at the Fermilab Tevatron collider.
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| 11. |
- Abazov, V. M., et al.
(author)
-
Inclusive Production of the X(4140) State in p(p)over-bar Collisions at D0
- 2015
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 115:23
-
Journal article (peer-reviewed)abstract
- We present a study of the inclusive production of the X(4140) state with the decay to the J/psi phi final state in hadronic collisions. Based on 10.4 fb(-1) of p (p) over bar 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 Gamma = 16.3 +/- 5.6 (stat) +/- 11.4 (syst) MeV are consistent with previous measurements.
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| 12. |
- Abazov, V. M., et al.
(author)
-
Measurement of spin correlation between top and antitop quarks produced in p(p)over-bar collisions at root s=1.96 TeV
- 2016
-
In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 757, s. 199-206
-
Journal article (peer-reviewed)abstract
- We present a measurement of the correlation between the spins of t and (t) over bar quarks produced in proton-antiproton collisions at the Tevatron Collider at a center-of-mass energy of 1.96 TeV. We apply a matrix element technique to dilepton and single-lepton+jets final states in data accumulated with the DO detector that correspond to an integrated luminosity of 9.7 fb(-1). The measured value of the correlation coefficient in the off-diagonal basis, O-off = 0.89 +/- 0.22 (stat + syst), is in agreement with the standard model prediction, and represents evidence for a top-antitop quark spin correlation difference from zero at a level of 4.2 standard deviations.
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| 13. |
- Abazov, V. M., et al.
(author)
-
Measurement of the B-s(0) Lifetime in the Flavor-Specific Decay Channel B-s(0)-> D-s(-)mu(+)nu X
- 2015
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 114:6
-
Journal article (peer-reviewed)abstract
- We present an updated measurement of the B-s(0) lifetime using the semileptonic decays B-s(0) -> D-s(-)mu(+)nu X, with D-s(-) -> phi pi(-) and phi -> K+K- (and the charge conjugate process). This measurement uses the full Tevatron Run II sample of proton-antiproton collisions at root s = 1.96 TeV, comprising an integrated luminosity of 10.4 fb(-1). We find a flavor-specific lifetime tau(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- mu(+)nu X decay with D- -> phi pi(-) and phi -> K+K-, yielding tau(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 tau(fs)(B-s(0))/tau(B-0) = 0.964 +/- 0.013(stat) +/- 0.007(syst).
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| 14. |
- Abazov, V. M., et al.
(author)
-
Measurement of the direct CP violating charge asymmetry in B-+/- -> mu(+/-)nu D-mu(0) decays
- 2017
-
In: Physical Review D. - 2470-0010 .- 2470-0029. ; 95:3
-
Journal article (peer-reviewed)abstract
- We present the first measurement of the CP violating charge asymmetry in B-+/- -> mu(+/-)nu D-mu(0) decays using the full Run II integrated luminosity of 10.4 fb(-1) in proton-antiproton collisions collected with the D0 detector at the Fermilab Tevatron Collider. We measure a difference in the yield of B- and B+ mesons in these decays by fitting the reconstructed invariant mass distributions. This results in an asymmetry of A(mu D0) = [-0.14 +/- 0.20] %, which is consistent with standard model predictions.
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| 15. |
- Abazov, V. M., et al.
(author)
-
Measurement of the Effective Weak Mixing Angle in p(p)over-bar -> Z/gamma* -> e(+)e(-) Events
- 2015
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 115:4
-
Journal article (peer-reviewed)abstract
- We present a measurement of the fundamental parameter of the standard model, the weak mixing angle sin(2)theta(l)(eff) which determines the relative strength of weak and electromagnetic interactions, in p (p) over bar -> Z/gamma* -> 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)theta(l)(eff) = 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.
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| 16. |
- Abazov, V. M., et al.
(author)
-
Measurement of the Effective Weak Mixing Angle in p¯p→Z/γ∗→ℓ+ℓ− Events
- 2018
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 120:24
-
Journal article (peer-reviewed)abstract
- We present a measurement of the effective weak mixing angle parameter sin(2)theta(l)(eff) in p (p) over bar -> Z/gamma* -> mu(+)mu(-) 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)theta(l)(eff)[mu mu] = 0.23016 +/- 0.00064 is further combined with the result from the D0 measurement in p (p) over bar -> Z/gamma* -> e(+)e(-) events, resulting in sin(2)theta(l)(eff)[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/gamma* to light quarks.
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| 17. |
- Abazov, V. M., et al.
(author)
-
Measurement of the electron charge asymmetry in p(p)over-bar -> W + X -> ev plus X decays in p(p)over-bar collisions at root S=1.96 TeV
- 2015
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 91:3
-
Journal article (peer-reviewed)abstract
- We present a measurement of the electron charge asymmetry in p (p) over bar -> W + X -> ev + X events at a center-of-mass energy of 1.96 TeV, using data corresponding to 9.7 fb(-1) of integrated luminosity collected with the D0 detector at the Fermilab Tevatron Collider. The asymmetry is measured as a function of the electron pseudorapidity and is presented in five kinematic bins based on the electron transverse energy and the missing transverse energy in the event. The measured asymmetry is compared with next-to-leading-order predictions in perturbative quantum chromodynamics and provides accurate information for the determination of parton distribution functions of the proton. This is the most precise lepton charge asymmetry measurement to date.
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| 18. |
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| 19. |
- Abazov, V. M., et al.
(author)
-
Measurement of the forward-backward asymmetry in Lambda(0)(b) and (Lambda)over-bar(b)(0) baryon production in p(p)over-bar collisions at root s=1.96 TeV
- 2015
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 91:7
-
Journal article (peer-reviewed)abstract
- We measure the forward-backward asymmetry in the production of Lambda(0)(b) and (Lambda) over bar (0)(b) baryons as a function of rapidity in p (p) over bar collisions at root s = 1.96 TeV using 10.4 fb(-1) of data collected with the D0 detector at the Fermilab Tevatron collider. The asymmetry is determined by the preference of Lambda(0)(b) or (Lambda) over bar (0)(b) particles to be produced in the direction of the beam protons or antiprotons, respectively. The measured asymmetry integrated over rapidity y in the range 0.1 < vertical bar y vertical bar < 2.0 is A = 0.04 +/- 0.07(stat) +/- 0.02(syst).
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| 20. |
- Abazov, V. M., et al.
(author)
-
Measurement of the Forward-Backward Asymmetry in the Production lof B-+/- Mesons in p(p)over-bar Collisions at root s=1.96 TeV
- 2015
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 114:5
-
Journal article (peer-reviewed)abstract
- We present a measurement of the forward-backward asymmetry in the production of B-+/- mesons, A(FB)(B-+/-) using B-+/- -> J/ Psi K-+/- decays in 10.4 fb(-1) of p (p) over bar collisions at root 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) over bar 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)] %.
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| 21. |
- Abazov, V. M., et al.
(author)
-
Measurement of the forward-backward asymmetry of Lambda and (Lambda)over-bar production in p(p)over-bar collisions
- 2016
-
In: PHYSICAL REVIEW D. - 2470-0010. ; 93:3
-
Journal article (peer-reviewed)abstract
- We study Lambda and (Lambda) over bar production asymmetries in p (p) over bar -> Lambda((Lambda) over bar )X, p (p) over bar -> J/psi Lambda((Lambda) over bar )X, and p (p) over bar -> mu(+/-)Lambda((Lambda) over bar )X events recorded by the D0 detector at the Fermilab Tevatron collider at root s = 1.96 TeV. We find an excess of Lambda's ((Lambda) over bar 's) produced in the proton (antiproton) direction. This forward-backward asymmetry is measured as a function of rapidity. We confirm that the (Lambda) over bar/Lambda production ratio, measured by several experiments with various targets and a wide range of energies, is a universal function of "rapidity loss," i.e., the rapidity difference of the beam proton and the lambda.
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| 22. |
- Abazov, V. M., et al.
(author)
-
Measurement of the inclusive t(t)over-bar production cross section in p(p)over-bar collisions at root s=1.96 TeV and determination of the top quark pole mass
- 2016
-
In: PHYSICAL REVIEW D. - 2470-0010. ; 94:9
-
Journal article (peer-reviewed)abstract
- The inclusive cross section of top quark-antiquark pairs produced in p (p) over bar collisions at root s = 1.96 TeV is measured in the lepton + jets and dilepton decay channels. The data sample corresponds to 9.7 fb(-1) of integrated luminosity recorded with the D0 detector during Run II of the Fermilab Tevatron Collider. Employing multivariate analysis techniques we measure the cross section in the two decay channels and we perform a combined cross section measurement. For a top quark mass of 172.5 GeV, we measure a combined inclusive top quark-antiquark pair production cross section of sigma(t<(t)over bar) = 7.26 +/- 0.13(stat)(-0.50)(+0.57) (syst) pb which is consistent with standard model predictions. We also perform a likelihood fit to the measured and predicted top quark mass dependence of the inclusive cross section, which yields a measurement of the pole mass of the top quark. The extracted value is m(t) = 172.8 +/- 1.1(theo)(-3.1)(+3.3) (exp) GeV.
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| 23. |
- Abazov, V. M., et al.
(author)
-
Measurement of the phi(eta)* distribution of muon pairs with masses between 30 and 500 GeV in 10.4 fb(-1) of p(p)over-bar collisions
- 2015
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 91:7
-
Journal article (peer-reviewed)abstract
- We present a measurement of the distribution of the variable phi(eta)* for muon pairs with masses between 30 and 500 GeV, using the complete run II data set collected by the D0 detector at the Fermilab Tevatron proton-antiproton collider. This corresponds to an integrated luminosity of 10.4 fb(-1) at root s = 1.96 TeV. The data are corrected for detector effects and presented in bins of dimuon rapidity and mass. The variable phi(eta)* probes the same physical effects as the Z/gamma* boson transverse momentum, but is less susceptible to the effects of experimental resolution and efficiency. These are the first measurements at any collider of the phi(eta)* distributions for dilepton masses away from the Z --> l(+)l(-) boson mass peak. The data are compared to QCD predictions based on the resummation of multiple soft gluons.
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| 24. |
- Abazov, V. M., et al.
(author)
-
Measurement of the ratio of inclusive cross sections sigma(p(p)over-bar) -> Z+2b jets/sigma(p((p)over-bar) -> Z+2 jets) in p((p)over-bar) collisions at root s=1.96 TeV
- 2015
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 91:5
-
Journal article (peer-reviewed)abstract
- We measure the ratio of cross sections, σ(pp¯→Z+2b jets)/σ(pp¯→Z+2 jets), for associated production of a Z boson with at least two jets with transverse momentum pjetT>20 GeV and pseudorapidity |ηjet|<2.5. This measurement uses data corresponding to an integrated luminosity of 9.7 fb−1 collected by the D0 experiment in Run II of Fermilab’s Tevatron pp¯ Collider at a center-of-mass energy of 1.96 TeV. The measured integrated ratio of 0.0236±0.0032 (stat)±0.0035 (syst) is in agreement with predictions from next-to-leading-order perturbative QCD and the Monte Carlo event generators pythia and alpgen.
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| 25. |
- Abazov, V. M., et al.
(author)
-
Measurement of the top quark mass using the matrix element technique in dilepton final states
- 2016
-
In: PHYSICAL REVIEW D. - 2470-0010. ; 94:3
-
Journal article (peer-reviewed)abstract
- We present a measurement of the top quark mass in p (p) over bar collisions at a center-of-mass energy of 1.96 TeV at the Fermilab Tevatron collider. The data were collected by the D0 experiment corresponding to an integrated luminosity of 9.7 fb(-1). The matrix element technique is applied to t (t) over bar events in the final state containing leptons (electrons or muons) with high transverse momenta and at least two jets. The calibration of the jet energy scale determined in the lepton + jets final state of t (t) over bar decays is applied to jet energies. This correction provides a substantial reduction in systematic uncertainties. We obtain a top quark mass of m(t) = 173.93 +/- 1.84 GeV.
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| 26. |
- Abazov, V. M., et al.
(author)
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Measurement of the W plus b-jet and W plus c-jet differential production cross sections in p (p)over-bar collisions at root s=1.96 TeV
- 2015
-
In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 743, s. 6-14
-
Journal article (peer-reviewed)abstract
- We present a measurement of the cross sections for the associated production of a W boson with at least one heavy quark jet, b or c, in proton-antiproton collisions. Data corresponding to an integrated luminosity of 8.7 fb(-1) recorded with the D0 detector at the Fermilab Tevatron p (p) over bar Collider at root s = 1.96 TeV are used to measure the cross sections differentially as a function of the jet transverse momenta in the range 20 to 150 GeV. These results are compared to calculations of perturbative QCD theory as well as predictions from Monte Carlo generators.
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| 27. |
- Abazov, V. M., et al.
(author)
-
Measurement of top quark polarization in t(t)over-bar lepton+jets final states
- 2017
-
In: PHYSICAL REVIEW D. - 2470-0010. ; 95:1
-
Journal article (peer-reviewed)abstract
- We present a measurement of top quark polarization in t (t) over bar pair production in p (p) over bar collisions at root s = 1.96 TeV using data corresponding to 9.7 fb(-1) of integrated luminosity recorded with the D0 detector at the Fermilab Tevatron Collider. We consider final states containing a lepton and at least three jets. The polarization is measured through the distribution of lepton angles along three axes: the beam axis, the helicity axis, and the transverse axis normal to the t (t) over bar production plane. This is the first measurement of top quark polarization at the Tevatron using lepton + jet final states and the first measurement of the transverse polarization in t (t) over bar production. The observed distributions are consistent with standard model predictions of nearly no polarization.
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| 28. |
- Abazov, V. M., et al.
(author)
-
Precise measurement of the top quark mass in dilepton decays using optimized neutrino weighting
- 2016
-
In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 752, s. 18-26
-
Journal article (peer-reviewed)abstract
- We measure the top quark mass in dilepton final states of t (t) over bar events in p (p) over bar collisions at root s = 1.96 TeV, using data corresponding to an integrated luminosity of 9.7 fb(-1) at the Fermilab Tevatron Collider. The analysis features a comprehensive optimization of the neutrino weighting method to minimize the statistical uncertainties. We also improve the calibration of jet energies using the calibration determined in t (t) over bar -> lepton + jets events, which reduces the otherwise limiting systematic uncertainty from the jet energy scale. The measured top quark mass is m(t) = 173.32 +/- 1.36(stat) +/- 0.85(syst) GeV.
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| 29. |
- Abazov, V. M., et al.
(author)
-
Precision measurement of the top-quark mass in lepton plus jets final states
- 2015
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 91:11
-
Journal article (peer-reviewed)abstract
- We measure the mass of the top quark in lepton + jets final states using the full sample of p (p) over bar collision data collected by the D0 experiment in Run II of the Fermilab Tevatron Collider at root 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 t (t) over bar 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.
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| 30. |
- Abazov, V. M., et al.
(author)
-
Search for Violation of CPT and Lorentz Invariance in B-s(0) Meson Oscillations
- 2015
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 115:16
-
Journal article (peer-reviewed)abstract
- We present the first search for CPT-violating effects in the mixing of B-s(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 B-s(0) -> mu D-+/-(s)+/- 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 Delta a(perpendicular to) < 1.2 x 10(-12) GeV and (-0.8 < Delta a(T) - 0.396 Delta a(Z) < 3.9) x 10(-13) GeV.
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| 31. |
- Abazov, V. M., et al.
(author)
-
Simultaneous measurement of forward-backward asymmetry and top polarization in dilepton final states from t(t)over-bar production at the Tevatron
- 2015
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 92:5
-
Journal article (peer-reviewed)abstract
- We present a simultaneous measurement of the forward-backward asymmetry and the top-quark polarization in t (t) over bar production in dilepton final states using 9.7 fb(-1) of proton-antiproton collisions at root s = 1.96 TeV with the D0 detector. To reconstruct the distributions of kinematic observables we employ a matrix element technique that calculates the likelihood of the possible t (t) over bar kinematic configurations. After accounting for the presence of background events and for calibration effects, we obtain a forward-backward asymmetry of A(t (t) over bar) = (15.0 +/- 6.4(stat) +/- 4.9(syst)) % and a top-quark polarization times spin analyzing power in the beam basis of kappa P = (7.2 +/- 10.5(stat) +/- 4.2(syst)) %, with a correlation of -56% between the measurements. If we constrain the forward-backward asymmetry to its expected standard model value, we obtain a measurement of the top polarization of kappa P = (11.3 +/- 9.1(stat) +/- 1.9(syst)) %. If we constrain the top polarization to its expected standard model value, we measure a forward-backward asymmetry of A(t (t) over bar) = (17.5 +/- 5.6(stat) +/- 3.1(syst)) %. A combination with the D0 A(t (t) over bar) measurement in the lepton + jets final state yields an asymmetry of A(t (t) over bar) = (11.8 +/- 2.5(stat) +/- 1.3(syst)) %. Within their respective uncertainties, all these results are consistent with the standard model expectations.
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| 32. |
- Abazov, V. M., et al.
(author)
-
Study of double parton interactions in diphoton plus dijet events in p<(p)over bar> collisions at root s = 1.96 TeV
- 2016
-
In: PHYSICAL REVIEW D. - 2470-0010. ; 93:5
-
Journal article (peer-reviewed)abstract
- We use a sample of diphoton + dijet events to measure the effective cross section of double parton interactions, which characterizes the area containing the interacting partons in proton-antiproton collisions, and find it to be sigma(eff) = 19.3 +/- 1.4(stat) +/- 7.8(syst) mb. The sample was collected by the D0 detector at the Fermilab Tevatron collider in p (p) over bar collisions at root s = 1.96 TeV and corresponds to an integrated luminosity of 8.7 fb(-1).
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| 33. |
- Abazov, V. M., et al.
(author)
-
Study of the X-+/-(5568) state with semileptonic decays of the B-s(0) meson
- 2018
-
In: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 97:9
-
Journal article (peer-reviewed)abstract
- We present a study of the X-+/-(5568) using semileptonic decays of the B-s(0) meson using the full run II integrated luminosity of 10.4 fb(-1) in proton-antiproton collisions at a center of mass energy of 1.96 TeV collected with the DO detector at the Fermilab Tevatron Collider. We report evidence for a narrow structure, X-+/-(5568), in the decay sequence X-+/-(5568) -> B-s(0) pi(+/-) where B-s(0)-> mu(-/+) (DsX)-X-+/-, D-s(+/-)-> phi pi(+/-)which is consistent with the previous measurement by the DO Collaboration in the hadronic decay mode, X-+/-(5568) -> B-s(0)pi(+/-) where B-s(0 )-> J/psi phi. The mass and width of this state are measured using a combined fit of the hadronic and semileptonic data, yielding m = 5566.9(-3.1)(+3.2)(stat)(-1.2)(+0.6)(syst) MeV/c(2), Gamma = 18.6(-6.1)(+7.9)(stat)(-3.8)(+3.5) (syst) McV/c(2) with a significance of 6.7 sigma.
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| 34. |
-
- 2019
-
Journal article (peer-reviewed)
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| 35. |
- Bolognesi, P., et al.
(author)
-
A study of the dynamical energy flow in uracil
- 2015
-
In: Journal of Physics, Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 635
-
Journal article (peer-reviewed)abstract
- The time resolved photoionization of C 1s in uracil following excitation of the neutral molecule by 260 nm pulses has been studied at LCLS.
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| 36. |
- Mucke, Melanie, et al.
(author)
-
Covariance mapping of two-photon double core hole states in C2H2 and C2H6 produced by an x-ray free electron laser
- 2015
-
In: New Journal of Physics. - : IOP Publishing. - 1367-2630. ; 17
-
Journal article (peer-reviewed)abstract
- Few-photon ionization and relaxation processes in acetylene (C2H2) and ethane (C2H6) were investigated at the linac coherent light source x-ray free electron laser (FEL) at SLAC, Stanford using a highly efficient multi-particle correlation spectroscopy technique based on a magnetic bottle. The analysis method of covariance mapping has been applied and enhanced, allowing us to identify electron pairs associated with double core hole (DCH) production and competing multiple ionization processes including Auger decay sequences. The experimental technique and the analysis procedure are discussed in the light of earlier investigations of DCH studies carried out at the same FEL and at third generation synchrotron radiation sources. In particular, we demonstrate the capability of the covariance mapping technique to disentangle the formation of molecular DCH states which is barely feasible with conventional electron spectroscopy methods.
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| 37. |
- Tachibana, T., et al.
(author)
-
Nanoplasma Formation by High Intensity Hard X-rays
- 2015
-
In: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 5
-
Journal article (peer-reviewed)abstract
- Using electron spectroscopy, we have investigated nanoplasma formation from noble gas clusters exposed to high-intensity hard-x-ray pulses at similar to 5 keV. Our experiment was carried out at the SPring-8 Angstrom Compact free electron LAser (SACLA) facility in Japan. Dedicated theoretical simulations were performed with the molecular dynamics tool XMDYN. We found that in this unprecedented wavelength regime nanoplasma formation is a highly indirect process. In the argon clusters investigated, nanoplasma is mainly formed through secondary electron cascading initiated by slow Auger electrons. Energy is distributed within the sample entirely through Auger processes and secondary electron cascading following photoabsorption, as in the hard x-ray regime there is no direct energy transfer from the field to the plasma. This plasma formation mechanism is specific to the hard-x-ray regime and may, thus, also be important for XFEL-based molecular imaging studies. In xenon clusters, photo-and Auger electrons contribute more significantly to the nanoplasma formation. Good agreement between experiment and simulations validates our modelling approach. This has wide-ranging implications for our ability to quantitatively predict the behavior of complex molecular systems irradiated by high-intensity hard x-rays.
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| 38. |
- Takanashi, T, et al.
(author)
-
Time-Resolved Measurement of Interatomic Coulombic Decay Induced by Two-Photon Double Excitation of Ne2
- 2017
-
In: Physical Review Letters. - 0031-9007. ; 118:3
-
Journal article (peer-reviewed)abstract
- The hitherto unexplored two-photon doubly excited states [Ne∗(2p-13s)]2 were experimentally identified using the seeded, fully coherent, intense extreme ultraviolet free-electron laser FERMI. These states undergo ultrafast interatomic Coulombic decay (ICD), which predominantly produces singly ionized dimers. In order to obtain the rate of ICD, the resulting yield of Ne2+ ions was recorded as a function of delay between the extreme ultraviolet pump and UV probe laser pulses. The extracted lifetimes of the long-lived doubly excited states, 390(-130/+450) fs, and of the short-lived ones, less than 150 fs, are in good agreement with ab initio quantum mechanical calculations.
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| 39. |
- Choubey, Sandhya, et al.
(author)
-
Singlet-triplet fermionic dark matter and LHC phenomenology
- 2018
-
In: European Physical Journal C. - : Springer New York LLC. - 1434-6044 .- 1434-6052. ; 78:4
-
Journal article (peer-reviewed)abstract
- It is well known that for the pure standard model triplet fermionic WIMP-type dark matter (DM), the relic density is satisfied around 2 TeV. For such a heavy mass particle, the production cross-section at 13 TeV run of LHC will be very small. Extending the model further with a singlet fermion and a triplet scalar, DM relic density can be satisfied for even much lower masses. The lower mass DM can be copiously produced at LHC and hence the model can be tested at collider. For the present model we have studied the multi jet (≥2j) + missing energy ([InlineEquation not available: see fulltext.]) signal and show that this can be detected in the near future of the LHC 13 TeV run. We also predict that the present model is testable by the earth based DM direct detection experiments like Xenon-1T and in future by Darwin.
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| 40. |
- Fukuzawa, H., et al.
(author)
-
Electron spectroscopy of rare-gas clusters irradiated by x-ray free-electron laser pulses from SACLA
- 2016
-
In: Journal of Physics B-Atomic Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 49:3
-
Journal article (peer-reviewed)abstract
- We have measured electron energy spectra and asymmetry parameters of Ar clusters and Xe clusters illuminated by intense x-rays at 5 and 5.5 keV. A velocity map imaging spectrometer was developed for this purpose and employed at an x-ray free-electron laser facility, SACLA in Japan. The cluster size dependence and the peak fluence dependence of the electron spectra and asymmetry parameters are discussed.
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| 41. |
- Fukuzawa, Hironobu, et al.
(author)
-
Real-time observation of X-ray-induced intramolecular and interatomic electronic decay in CH2I2
- 2019
-
In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1
-
Journal article (peer-reviewed)abstract
- The increasing availability of X-ray free-electron lasers (XFELs) has catalyzed the development of single-object structural determination and of structural dynamics tracking in real-time. Disentangling the molecular-level reactions triggered by the interaction with an XFEL pulse is a fundamental step towards developing such applications. Here we report real-time observations of XFEL-induced electronic decay via short-lived transient electronic states in the diiodomethane molecule, using a femtosecond near-infrared probe laser. We determine the lifetimes of the transient states populated during the XFEL-induced Auger cascades and find that multiply charged iodine ions are issued from short-lived (∼20 fs) transient states, whereas the singly charged ones originate from significantly longer-lived states (∼100 fs). We identify the mechanisms behind these different time scales: contrary to the short-lived transient states which relax by molecular Auger decay, the long-lived ones decay by an interatomic Coulombic decay between two iodine atoms, during the molecular fragmentation. © 2019, The Author(s).
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| 42. |
- Iablonskyi, D., et al.
(author)
-
Interatomic Coulombic Decay Processes after Multiple Valence Excitations in Ne Clusters
- 2015
-
In: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 635, s. 112067-112067
-
Conference paper (peer-reviewed)abstract
- We present a comprehensive analysis of autoionization processes in Ne clusters (similar to 5000 atoms) after multiple valence excitations by free electron laser radiation. The evolution from 2-body interatomic Coulombic decay (ICD) to 3-body ICD is demonstrated when changing from surface to bulk Frenkel exciton excitation. Super Coster-Kronig type 2-body ICD is observed at Wannier exciton which quenches the main ICD channel.
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| 43. |
- Iablonskyi, D., et al.
(author)
-
Slow Interatomic Coulombic Decay of Multiply Excited Neon Clusters
- 2016
-
In: Physical Review Letters. - 0031-9007. ; 117:27
-
Journal article (peer-reviewed)abstract
- Ne clusters (∼5000 atoms) were resonantly excited (2p→3s) by intense free electron laser (FEL) radiation at FERMI. Such multiply excited clusters can decay nonradiatively via energy exchange between at least two neighboring excited atoms. Benefiting from the precise tunability and narrow bandwidth of seeded FEL radiation, specific sites of the Ne clusters were probed. We found that the relaxation of cluster surface atoms proceeds via a sequence of interatomic or intermolecular Coulombic decay (ICD) processes while ICD of bulk atoms is additionally affected by the surrounding excited medium via inelastic electron scattering. For both cases, cluster excitations relax to atomic states prior to ICD, showing that this kind of ICD is rather slow (picosecond range). Controlling the average number of excitations per cluster via the FEL intensity allows a coarse tuning of the ICD rate.
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| 44. |
- Jin, L. Y., et al.
(author)
-
Long noncoding RNA MEG3 regulates LATS2 by promoting the ubiquitination of EZH2 and inhibits proliferation and invasion in gallbladder cancer
- 2018
-
In: Cell Death & Disease. - : Springer Science and Business Media LLC. - 2041-4889. ; 9
-
Journal article (peer-reviewed)abstract
- Gallbladder cancer (GBC) is the most common type of biliary tract cancer worldwide. Long noncoding RNAs (lncRNAs) play essential roles in physiological and pathological development. LncRNA MEG3, a tumor suppressor, has been reported to play important roles in some cancers, but the role of MEG3 in GBC remains largely unknown. The purpose of the present study was to explore the role of MEG3 in proliferation and invasion and the potential molecular mechanism in GBC. We found that MEG3 was downregulated in GBC tissues and cells, and low expression of MEG3 was correlated with poor prognostic outcomes in patients. Overexpression of MEG3 inhibited GBC cell proliferation and invasion, induced cell apoptosis and decreased tumorigenicity in nude mice. Moreover, we found that MEG3 was associated with EZH2 and attenuated EZH2 by promoting its ubiquitination. Furthermore, MEG3 executed its functions via EZH2 to regulate the downstream target gene LATS2. Taken together, these findings suggest that MEG3 is an effective target for GBC therapy and may facilitate the development of lncRNA-directed diagnostics and therapeutics against GBC.
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| 45. |
- Jacobs, G. S., et al.
(author)
-
Multiple Deeply Divergent Denisovan Ancestries in Papuans
- 2019
-
In: Cell. - : Elsevier BV. - 0092-8674 .- 1097-4172. ; 177:4, s. 1010-1021.e32
-
Journal article (peer-reviewed)abstract
- Genome sequences are known for two archaic hominins—Neanderthals and Denisovans—which interbred with anatomically modern humans as they dispersed out of Africa. We identified high-confidence archaic haplotypes in 161 new genomes spanning 14 island groups in Island Southeast Asia and New Guinea and found large stretches of DNA that are inconsistent with a single introgressing Denisovan origin. Instead, modern Papuans carry hundreds of gene variants from two deeply divergent Denisovan lineages that separated over 350 thousand years ago. Spatial and temporal structure among these lineages suggest that introgression from one of these Denisovan groups predominantly took place east of the Wallace line and continued until near the end of the Pleistocene. A third Denisovan lineage occurs in modern East Asians. This regional mosaic suggests considerable complexity in archaic contact, with modern humans interbreeding with multiple Denisovan groups that were geographically isolated from each other over deep evolutionary time.
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| 46. |
- Mondal, B, et al.
(author)
-
Integrative functional genomic analysis identifies epigenetically regulated fibromodulin as an essential gene for glioma cell migration.
- 2017
-
In: Oncogene. - : Springer Science and Business Media LLC. - 0950-9232 .- 1476-5594. ; 36, s. 71-83
-
Journal article (peer-reviewed)abstract
- An integrative functional genomics study of multiple forms of data are vital for discovering molecular drivers of cancer development and progression. Here, we present an integrated genomic strategy utilizing DNA methylation and transcriptome profile data to discover epigenetically regulated genes implicated in cancer development and invasive progression. More specifically, this analysis identified fibromodulin (FMOD) as a glioblastoma (GBM) upregulated gene because of the loss of promoter methylation. Secreted FMOD promotes glioma cell migration through its ability to induce filamentous actin stress fiber formation. Treatment with cytochalasin D, an actin polymerization inhibitor, significantly reduced the FMOD-induced glioma cell migration. Small interfering RNA and small molecule inhibitor-based studies identified that FMOD-induced glioma cell migration is dependent on integrin-FAK-Src-Rho-ROCK signaling pathway. FMOD lacking C-terminus LRR11 domain (ΔFMOD), which does not bind collagen type I, failed to induce integrin and promote glioma cell migration. Further, FMOD-induced integrin activation and migration was abrogated by a 9-mer wild-type peptide from the FMOD C-terminus. However, the same peptide with mutation in two residues essential for FMOD interaction with collagen type I failed to compete with FMOD, thus signifying the importance of collagen type I-FMOD interaction in integrin activation. Chromatin immunoprecipitation-PCR experiments revealed that transforming growth factor beta-1 (TGF-β1) regulates FMOD expression through epigenetic remodeling of FMOD promoter that involved demethylation and gain of active histone marks with a simultaneous loss of DNMT3A and EZH2 occupancy, but enrichment of Sma- and Mad-related protein-2 (SMAD2) and CBP. FMOD silencing inhibited the TGF-β1-mediated glioma cell migration significantly. In univariate and multivariate Cox regression analysis, both FMOD promoter methylation and transcript levels predicted prognosis in GBM. Thus, this study identified several epigenetically regulated alterations responsible for cancer development and progression. Specifically, we found that secreted FMOD as an important regulator of glioma cell migration downstream of TGF-β1 pathway and forms a potential basis for therapeutic intervention in GBM.
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| 47. |
- Mondal, Debasish, et al.
(author)
-
Polycaprolactone-based biomaterials for tissue engineering and drug delivery: Current scenario and challenges
- 2016
-
In: International Journal of Polymeric Materials. - : TAYLOR & FRANCIS AS. - 0091-4037 .- 1563-535X. ; 65:5, s. 255-265
-
Journal article (peer-reviewed)abstract
- Recently, poly (epsilon-caprolactone) (PCL) has gained a lot of attention, and shown great potential in biomedical applications. Among synthetic polymers, PCL is one of the easiest to process and manipulate into a large range of shapes and sizes due to its low melting temperature and its superior viscoelastic properties. In this review article the authors focus mainly on the properties of PCL-based biomaterials relevant to drug delivery and tissue engineering applications. The authors provide an insight into the recent developments and challenges of PCL-based biomaterials as a critical component of new therapeutic strategies for many diseases.
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| 48. |
- Olmeda, David, et al.
(author)
-
Whole-body imaging of lymphovascular niches identifies pre-metastatic roles of midkine
- 2017
-
In: Nature. - : NATURE PUBLISHING GROUP. - 0028-0836 .- 1476-4687. ; 546:7660, s. 676-680
-
Journal article (peer-reviewed)abstract
- Cutaneous melanoma is a type of cancer with an inherent potential for lymph node colonization, which is generally preceded by neolymphangiogenesis(1-3). However, sentinel lymph node removal does not necessarily extend the overall survival of patients with melanoma(4,5). Moreover, lymphatic vessels collapse and become dysfunctional as melanomas progress(6,7). Therefore, it is unclear whether (and how) lymphangiogenesis contributes to visceral metastasis. Soluble and vesicle-associated proteins secreted by tumours and/or their stroma have been proposed to condition pre-metastatic sites in patients with melanoma(8-14). Still, the identities and prognostic value of lymphangiogenic mediators remain unclear(2,14). Moreover, our understanding of lymphangiogenesis (in melanomas and other tumour types) is limited by the paucity of mouse models for live imaging of distal pre-metastatic niches(15). Injectable lymphatic tracers have been developed(7), but their limited diffusion precludes whole-body imaging at visceral sites(16). Vascular endothelial growth factor receptor 3 (VEGFR3) is an attractive 'lymphoreporter' 17 because its expression is strongly downregulated in normal adult lymphatic endothelial cells, but is activated in pathological situations such as inflammation and cancer(17,18). Here, we exploit this inducibility of VEGFR3 to engineer mouse melanoma models for whole-body imaging of metastasis generated by human cells, clinical biopsies or endogenously deregulated oncogenic pathways. This strategy revealed early induction of distal pre-metastatic niches uncoupled from lymphangiogenesis at primary lesions. Analyses of the melanoma secretome and validation in clinical specimens showed that the heparin-binding factor midkine is a systemic inducer of neo-lymphangiogenesis that defines patient prognosis. This role of midkine was linked to a paracrine activation of the mTOR pathway in lymphatic endothelial cells. These data support the use of VEGFR3 reporter mice as a 'MetAlert' discovery platform for drivers and inhibitors of metastasis.
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| 49. |
- Zhaunerchyk, Vitali, et al.
(author)
-
Disentangling formation of multiple-core holes in aminophenol molecules exposed to bright X-FEL radiation
- 2015
-
In: Journal of Physics B. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 48:24
-
Journal article (peer-reviewed)abstract
- Competing multi-photon ionization processes, some leading to the formation of double core hole states, have been examined in 4-aminophenol. The experiments used the linac coherent light source (LCLS) x-ray free electron laser, in combination with a time-of-flight magnetic bottle electron spectrometer and the correlation analysis method of covariance mapping. The results imply that 4-aminophenol molecules exposed to the focused x-ray pulses of the LCLS sequentially absorb more than two x-ray photons, resulting in the formation of multiple core holes as well as in the sequential removal of photoelectrons and Auger electrons (so-called PAPA sequences).
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