| 1. |
- Ablikim, M., et al.
(author)
-
Measurement of the $D\to K^-\pi^+$ strong phase difference in $\psi(3770)\to D^0\overline{D}{}^0$
- 2014
-
In: PHYSICS LETTERS B. - : Elsevier BV. - 0370-2693. ; 734
-
Journal article (peer-reviewed)abstract
- We study $D^0\overline{D}{}^0$ pairs produced in $e^+e^-$ collisions at $\sqrt{s}=3.773$ GeV using a data sample of 2.92 fb$^{-1}$ collected with the BESIII detector. We measure the asymmetry $\mathcal{A}^{CP}_{K\pi}$ of the branching fractions of $D \to K^-\pi^+$ in $CP$-odd and $CP$-even eigenstates to be $(12.7\pm1.3\pm0.7)\times10^{-2}$. $\mathcal{A}^{CP}_{K\pi}$ can be used to extract the strong phase difference $\delta_{K\pi}$ between the doubly Cabibbo-suppressed process $\overline{D}{}^{0}\to K^-\pi^+$ and the Cabibbo-favored process $D^0\to K^- \pi^+$. Using world-average values of external parameters, we obtain $\cos\delta_{K\pi} = 1.02\pm0.11\pm0.06\pm0.01$. Here, the first and second uncertainties are statistical and systematic, respectively, while the third uncertainty arises from the external parameters. This is the most precise measurement of $\delta_{K\pi}$ to date.
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| 2. |
- Ablikim, M., et al.
(author)
-
Observation of e(+)e(-) -> pi(0)pi(0)h(c) and a Neutral Charmoniumlike Structure Z(c)(4020)(0)
- 2014
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 113:21, s. 212002-
-
Journal article (peer-reviewed)abstract
- Using data collected with the BESIII detector operating at the Beijing Electron Positron Collider at center-of-mass energies of root s = 4.23, 4.26, and 4.36 GeV, we observe e(+)e(-) -> pi(0)pi(0)h(c) for the first time. The Born cross sections are measured and found to be about half of those of e(+)e(-) -> pi(+)pi(-)h(c) within less than 2 sigma. In the pi(0)h(c) mass spectrum, a structure at 4.02 GeV/c(2) is found. It is most likely to be the neutral isospin partner of the Z(c)(4020)(+/-) observed in the process of e(+)e(-) -> pi(+)pi(-)h(c) being found. A fit to the pi(0)h(c) invariant mass spectrum, with the width of the Z(c)(4020)(0) fixed to that of its charged isospin partner and possible interferences with non-Z(c)(4020)(0) amplitudes neglected, gives a mass of (4023.9 +/- 2.2 +/- 3.8) MeV/c(2) for the Z(c)(4020)(0), where the first error is statistical and the second systematic.
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| 3. |
- Ablikim, M., et al.
(author)
-
Observation of $e^+e^− → γX$(3872) at BESIII
- 2014
-
In: PHYSICAL REVIEW LETTERS. - 1079-7114. ; 112:9
-
Journal article (peer-reviewed)abstract
- With data samples collected with the BESIII detector operating at the BEPCII storage ring at center-of-mass energies from 4.009 to 4.420 GeV, the process $e^{+} e^{-} \to \gamma X(3872)$ is observed for the first time with a statistical significance of $6.3\sigma$. The measured mass of the $X(3872)$ is ($3871.9\pm 0.7_{\rm stat.}\pm 0.2_{\rm sys.}$) MeV/$c^2$, in agreement with previous measurements. Measurements of the product of the cross section $\sigma[e^{+} e^{-} \to \gamma X(3872)]$ and the branching fraction $\mathcal{B}[X(3872) \to \pi^{+} \pi^{-} J/\psi]$ at center-of-mass energies 4.009, 4.229, 4.260, and 4.360 GeV are reported. Our measurements are consistent with expectations for the radiative transition process $Y(4260) \to \gamma X(3872)$.
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| 4. |
- Ablikim, M., et al.
(author)
-
Observation of electromagnetic Dalitz decays J/\psi \to P e^+e^-
- 2014
-
In: PHYSICAL REVIEW D. - 2470-0010 .- 1550-7998 .- 1550-2368. ; 89:9
-
Journal article (peer-reviewed)abstract
- Based on a sample of (225.3\pm2.8)\times 10^{6} J/\psi events collected with the BESIII detector, the electromagnetic Dalitz decays of J/\psi \to P e^+e^-(P=\eta'/\eta/\pi^0) are studied. By reconstructing the pseudoscalar mesons in various decay modes, the decays J/\psi \to \eta' e^+e^-, J/\psi \to \eta e^+e^- and J/\psi \to \pi^0 e^+e^- are observed for the first time. The branching fractions are determined to be \mathcal{B}(J/\psi\to \eta' e^+e^-) = (5.81\pm0.16\pm0.31)\times10^{-5}, \mathcal{B}(J/\psi\to \eta e^+e^-) = (1.16\pm0.07\pm0.06)\times10^{-5}, and \mathcal{B}(J/\psi\to \pi^0 e^+e^-)=(7.56\pm1.32\pm0.50)\times10^{-7}, where the first errors are statistical and the second ones systematic.
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| 5. |
- Ablikim, M., et al.
(author)
-
Precision measurements of $B(D^+ \rightarrow \mu^+ \nu_{\mu})$, the pseudoscalar decay constant $f_{D^+}$, and the quark mixing matrix element $|V_{\rm cd}|$
- 2014
-
In: PHYSICAL REVIEW D. - 2470-0010 .- 1550-7998 .- 1550-2368. ; 89:5
-
Journal article (peer-reviewed)abstract
- We report a measurement of the branching fraction $B(D^+ \rightarrow \mu^+ \nu_{\mu}) = [3.71 \pm 0.19 (\rm stat) \pm 0.06 (\rm sys)]\times 10^{-4}$ based on 2.92 ${\rm fb^{-1}}$ of data accumulated at $\sqrt{s}=3.773$ GeV with the BESIII detector at the BEPCII collider. This measurement, in conjunction with the Cabibbo-Kobayashi-Maskawa matrix element $|V_{\rm cd}|$ determined from a global Standard Model fit, implies a value for the weak decay constant $f_{D^+}=(203.2 \pm 5.3 \pm 1.8)$ MeV. Additionally, using this branching fraction measurement together with a Lattice QCD prediction for $f_{D^+}$, we find $|V_{\rm cd}|=0.2210\pm 0.0058 \pm 0.0047$. In either case, these are the most precise results for these quantities to date.
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| 6. |
- Ablikim, M., et al.
(author)
-
Search for the weak decays J/psi -> D-s(()*()-) e(+)nu(e) + c.c.
- 2014
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 90:11, s. 112014-
-
Journal article (peer-reviewed)abstract
- Using a sample of 2.25 x 10(8) J/psi events collected with the BESIII detector at the BEPCII collider, we search for the J/psi semileptonic weak decay J/psi -> D-s(-) e(+)nu(e) +c.c. with a much higher sensitivity than previous searches. We also perform the first search for J/psi -> D-s(*-) e(+) nu(e) + c.c. No significant excess of a signal above background is observed in either channel. At the 90% confidence level, the upper limits are determined to be B(J/psi -> D-s(-) e(+) nu(e) + c.c.) < 1.3 x 10(-6) and B(J/psi -> D-s*(-) e(+) nu(e) + c.c.) < 1.8 x 10(-6), respectively. Both are consistent with Standard Model predictions.
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| 7. |
- Ablikim, M., et al.
(author)
-
Amplitude analysis of the D+ -> K-S(0)pi + (0)(pi) Dalitz plot
- 2014
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:5, s. 052001-
-
Journal article (peer-reviewed)abstract
- We perform an analysis of the D+ -> K-S(0)pi + (0)(pi) Dalitz plot using a data set of 2.92 fb(-1) of e(+) e(-) collisions at the (3770) mass accumulated by the BESIII experiment, in which 166694 candidate events are selected with a background of 15.1%. The Dalitz plot is found to be well represented by a combination of six quasitwo- body decay channels [k(SP)(0)(+) (1450)(+,) ] plus a small nonresonant component. Using the fit fractions from this analysis, partial branching ratios are updated with higher precision than previous measurements.
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| 8. |
- Ablikim, M., et al.
(author)
-
Measurement of chi(cJ) decaying into eta ' K+K-
- 2014
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:7, s. 074030-
-
Journal article (peer-reviewed)abstract
- Using (106.41 +/- 0.86) x 10(6) Psi(3686) events collected with the BESIII detector at BEPCII, we study for the first time the decay chi(cJ) -> eta'K+K- (J = 1, 2), where eta' -> gamma rho(0) and eta' -> eta pi(+)pi(-). A partial wave analysis in the covariant tensor amplitude formalism is performed for the decay chi(c1) -> eta'K+K-. Intermediate processes chi(c1) -> eta'f(2)'(1525) chi(c1) -> K-0*(1430)K-+/-(-/+) (K-0*(1430)(+/-) -> eta'K-+/-) are observed with statistical significances larger than 5 sigma, and their branching fractions are measured.
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| 9. |
- Ablikim, M., et al.
(author)
-
Measurement of the branching fraction for psi(3686) -> omega K+K-
- 2014
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:11, s. 112006-
-
Journal article (peer-reviewed)abstract
- With 1.06 x 10(8) psi(3686) events collected with the BESIII detector, the branching fraction of psi(3686) -> omega K+K- is measured to be (1.54 +/- 0.04 +/- 0.11) x 10(-4). This is the most precise result to date, due to the largest psi(3686) sample, improved signal reconstruction efficiency, good simulation of the detector performance, and a more accurate knowledge of the continuum contribution. Using the branching fraction of J/psi -> omega K+K-, the ratio B(psi(3868) -> K+K-)/B(J/psi -> K+K-) is determined to be (18.4 +/- 3.7)%. This constitutes a significantly improved test of the 12% rule, with the uncertainty now dominated by the J/psi branching fraction.
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| 10. |
- Ablikim, M., et al.
(author)
-
Observation of e(+)e(-) -> gamma X(3872) at BESIII
- 2014
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 112:9, s. 092001-
-
Journal article (peer-reviewed)abstract
- With data samples collected with the BESIII detector operating at the BEPCII storage ring at center-of-mass energies from 4.009 to 4.420 GeV, the process e(+)e(-) -> gamma X(3872) is observed for the first time with a statistical significance of 6.3 sigma. The measured mass of the X(3872) is (3871.9 +/- 0.7(stat) +/- 0.2(syst)) MeV/c(2), in agreement with previous measurements. Measurements of the product of the cross section sigma[e(+)e(-) -> gamma X(3872)] and the branching fraction B [X(3872) -> pi(+)pi(-)J/psi] at center-of-mass energies 4.009, 4.229, 4.260, and 4.360 GeV are reported. Our measurements are consistent with expectations for the radiative transition process Y(4260) -> gamma X(3872).
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| 11. |
- Ablikim, M., et al.
(author)
-
Observation of eta' -> pi(+) pi(-) pi(+) pi(-) and eta' -> pi(+) pi(-) pi(0) pi(0)
- 2014
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 112:25, s. 251801-
-
Journal article (peer-reviewed)abstract
- Using a sample of 1.3 x 10(9) J/psi events collected with the BESIII detector, we report the first observation of eta' -> pi(+) pi(-) pi(+) pi(-) and eta' -> pi(+) pi(-) pi(0) pi(0). The measured branching fractions are B(eta' -> pi(+) pi(-) pi(+) pi(-)) = [8.53 +/- 0.69(stat.) +/- 0.64(syst.)] x 10(-5) and B(eta' -> pi(+) pi(-) pi(0) pi(0)) = [1.82 +/- 0.35(stat.) +/- 0.18(syst.)] x 10(-4), which are consistent with theoretical predictions based on a combination of chiral perturbation theory and vector-meson dominance.
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| 12. |
- Ablikim, M., et al.
(author)
-
Observation of J/psi -> p(p)over-bara(0)(980) at BESIII
- 2014
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 90:5, s. 052009-
-
Journal article (peer-reviewed)abstract
- Using 2.25 x 10(8) J/psi events collected with the BESIII detector at the BEPCII storage rings, we observe for the first time the process J/psi -> p (p) over bara(0)(980) -> pi(0)eta with a significance of 6.5 sigma (3.2 sigma including systematic uncertainties). The product branching fraction of J/psi -> p (p) over bara(0)(980) -> p (p) over bara(0)pi(0)eta is measured to be (6.8 +/- 1.2 +/- 1.3) x 10(-5), where the first error is statistical and the second is systematic. This measurement provides information on the a(0) production near threshold coupling to p (p) over bar and improves the understanding of the dynamics of J/psi decays to four-body processes.
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| 13. |
- Ablikim, M., et al.
(author)
-
Observation of the decay psi(3686) -> Lambda(Sigma)over-bar(+/-) pi(-/+) + c.c
- 2013
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 88:11, s. 112007-
-
Journal article (peer-reviewed)abstract
- Using a sample of 1:06 X 10(8) psi(3686) events collected with the BESIII detector, we present the first observation of the decays of psi(3686) -> Lambda(Sigma) over bar (+) pi(-) + c.c. and psi(3686) -> Lambda(Sigma) over bar (-) pi(+) + c.c. The branching fractions are measured to be B(psi(3686) -> Lambda(Sigma) over bar (+) pi(-) + c.c.) = (1.40 +/- 0.03 +/- 0.13) X 10(-4) and B(psi(3686) -> Lambda (Sigma) over bar (-) pi(+) + c.c.) = (1.54 +/- 0.04 +/- 0.13) X 10(-4) where the first errors are statistical and the second ones systematic.
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| 14. |
- Ablikim, M., et al.
(author)
-
Precision measurement of the mass of the tau lepton
- 2014
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 90:1
-
Journal article (peer-reviewed)abstract
- An energy scan near the tau pair production threshold has been performed using the BESIII detector. About 24 pb(-1) of data, distributed over four scan points, were collected. This analysis is based on t pair decays to ee, e mu, eh, h, hh, e.,. and p. final states, where h denotes a charged p or K. The mass of the t lepton is measured from a maximum likelihood fit to the t pair production cross- section data to be m(tau) = 1776.91 +/- 0.12_0.10 - 0.13 _ MeV/c(2), which is currently the most precise value in a single measurement.
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| 15. |
- Ablikim, M., et al.
(author)
-
Search for C-parity violation in J/psi -> gamma gamma and gamma phi
- 2014
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 90:9, s. 092002-
-
Journal article (peer-reviewed)abstract
- Using 1.06 x 10(8) psi(3686) events recorded in e(+)e(-) collisions at root s = 3.686 GeV with the BESIII at the BEPCII collider, we present searches for C-parity violation in J/psi -> gamma gamma and gamma phi decays via psi(3686) -> J/psi pi(+)pi(-). No significant signals are observed in either channel. Upper limits on the branching fractions are set to be B(J/psi -> gamma gamma) < 2.7 x 10(-7) and B(J/psi -> gamma phi) < 1.4 x 10(-6) at the 90% confidence level. The former is one order of magnitude more stringent than the previous upper limit, and the latter represents the first limit on this decay channel.
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| 16. |
- Ablikim, M., et al.
(author)
-
Search for eta(c)(2S)h(c) -> p(p)over-bar decays and measurements of the chi(cJ) -> p(p)over-bar branching fractions
- 2013
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 88:11, s. 112001-
-
Journal article (peer-reviewed)abstract
- Using a sample of 1.06 x 10(8)psi(3686) events collected with the BESIII detector at BEPCII, the decays eta(c)(2S) -> p (p) over bar and h(c) -> p (p) over bar are searched for, where eta(c)(2S) and h(c) are reconstructed in the decay chains psi(3686) -> gamma eta(c)(2S), eta(c)(2S) -> p (p) over bar and psi(3686) -> pi(0)h(c), h(c) -> p (p) over bar, respectively. No significant signals are observed. The upper limits of the product branching fractions are determined to be B(psi(3686) -> gamma eta(c)(2S)) x B(eta(c)(2S) -> p (p) over bar) < 1.4 x 10(-6) and B(psi(3686) -> pi(0)h(c)) x B(h(c) -> p<(p)over bar>) < 1.3 x 10(-7) at the 90% C.L.. The branching fractions for chi(cJ) -> p<(p)over bar> (J = 0, 1, 2) are also measured to be (24.5 +/- 0.8 +/- 1.3, 8.6 +/- 0.5 +/- 0.5, 8.4 +/- 0.5 +/- 0.5) x 10(-5), which are the world's most precise measurements.
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| 17. |
- Ablikim, M., et al.
(author)
-
Search for the radiative transitions Psi(3770) -> gamma eta(c) and gamma eta(c) (2S)
- 2014
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:11, s. 112005-
-
Journal article (peer-reviewed)abstract
- By using a 2.92 fb-1 data sample taken at pffisffiffi 3.773 GeV with the BESIII detector operating at the BEPCII collider, we search for the radiative transitions.d3770c and cd2S through the hadronic decays cdcd2S. K0 SK p. No significant excess of signal events above background is observed. We set upper limits at a 90% confidence level for the product branching fractions to be Bdd3770cxBd.c. K0 SK k p < 1.6x10-5 and Bd.d3770cd2SxBd.cd2S. K0 SK p<5.6x10-6. Combining our result with world-average values of Bd.cd.cd2S. K0 SK p, we find the branching fractions Bd.d3770c< 6.8 x 10-4 and Bd.d3770cd2S< 2.0 x 10-3 at a 90% confidence level.
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| 18. |
- Ablikim, M., et al.
(author)
-
Search for the rare decays J/y -> D-s(-) rho(+) and J/psi -> <(D)over bar(0)<(K)over bar*(0)
- 2014
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:7, s. 071101-
-
Journal article (peer-reviewed)abstract
- A search for the rare decays of J/psi -> D-S(-) rho(+) + c.c. and J/psi -> <(D)over bar(0)<(K)over bar*(0) + c.c. is performed with a data sample of 225.3-million J/psi events collected with the Beijing Spectrometer III detector. No evident signal is observed. Upper limits on the branching fractions are determined to be beta(J/psi -> D-S(-)rho(+) + c.c.) < 1.3 x 10(-5) and beta(J/psi -> <(D)over bar(0)<(K)over bar*(0) + c.c.) < 2.5 x 10(-6) at the 90% confidence level.
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| 19. |
- Ablikim, M., et al.
(author)
-
Study of e(+)e(-) -> p(p)over-bar in the vicinity of psi(3770)
- 2014
-
In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 735, s. 101-107
-
Journal article (peer-reviewed)abstract
- Using 2917 pb(-1) of data accumulated at 3.773 GeV, 44.5 pb(-1) of data accumulated at 3.65 GeV and data accumulated during a psi(3770) line-shape scan with the BESIII detector, the reaction e(+)e(-) -> p (p) over bar is studied considering a possible interference between resonant and continuum amplitudes. The cross section of e(+)e(-) -> psi(3770) -> p (p) over bar, sigma(e(+)e(-)-> psi(3770) -> p (p) over bar), is found to have two solutions, determined to be (0.059(-0.020)(+0.070) +/- 0.012) pb with the phase angle phi = (255.8(-26.6)(+39.0) +/- 4.8). (< 0.166 pb at the 90% confidence level), or sigma(e(+)e(-) -> psi(3770) -> p<(p)over bar>) = (2.57(-0.13)(+0.12) +/- 0.12) pb with phi = (266.9(-6.3)(+6.1) +/- 0.9)degrees both of which agree with a destructive interference. Using the obtained cross section of psi(3770) -> p (p) over bar, the cross section of p (p) over bar -> psi(3770), which is useful information for the future PANDA experiment, is estimated to be either (9.8(-3.9)(+11.8)) nb (< 27.5 nb at 90% C.L.) or (425.6(-43.7)(+42.9)) nb. (C) 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license.
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| 20. |
- Ablikim, M., et al.
(author)
-
Study of e(+)e(-) -> p(p)over-bar pi(0) in the vicinity of the psi(3770)
- 2014
-
In: Physical Review D. - 1550-7998 .- 1550-2368. ; 90:3, s. 032007-
-
Journal article (peer-reviewed)abstract
- The process e(+)e(-) -> p (p) over bar pi(0) has been studied by analyzing data collected at root s = 3.773 GeV, root s = 3.650 GeV, and during a psi(3770) line shape scan with the BESIII detector at the BEPCII collider. The Born cross section of p (p) over bar pi(0) in the vicinity of the psi(3770) is measured, and the Born cross section of psi(3770) -> p (p) over bar pi(0) is extracted considering interference between resonant and continuum production amplitudes. Two solutions with the same probability and a significance of 1.5 sigma are found. The solutions for the Born cross section of psi(3770) -> p (p) over bar pi(0) are 33.8 +/- 1.8 +/- 2.1 pb and 0.06(-0.04-0.01)(+0.10+0.01) pb (< 0.22 pb at a 90% confidence level). Using the estimated cross section and a constant decay amplitude approximation, the cross section sigma(p<(p)over bar> -> psi(3770)pi(0)) is calculated for the kinematic situation of the planned (p) over bar ANDA experiment. The maximum cross section corresponding to the two solutions is expected to be less than 0.79 nb at 90% confidence level and 122 +/- 10 nb at a center-of-mass energy of 5.26 GeV.
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| 21. |
- Klionsky, Daniel J., et al.
(author)
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Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
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In: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
-
Research review (peer-reviewed)abstract
- In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
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| 22. |
- Ai, Yuejie, 1982-, et al.
(author)
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Exploring concerted effects of base pairing and stacking on the excited-state nature of DNA oligonucleotides by DFT and TD-DFT studies
- 2011
-
In: International Journal of Quantum Chemistry. - : Wiley. - 0020-7608 .- 1097-461X. ; 111:10, s. 2366-2377
-
Journal article (peer-reviewed)abstract
- We have taken (dA)5, (dT)5, and (dA)5•(dT)5 as model systems to study concerted effects of base pairing and stacking on excited-state nature of DNA oligonucleotides using density functional theory (DFT) and time dependent DFTmethods. The spectroscopic states are determined to be of a partial A →A charge transfernature in the A•T oligonucleotides. The T → T charge-transfer transitionsproduce dark states, which are hidden in the energy region of the steady-stateabsorption spectra. This is different from the previous assignment that the T → Tcharge-transfer transition is responsible for a shoulder at the red side of the first strongabsorption band. The A →T charge-transfer states were predicted to have relativelyhigh energies in the A•T oligonucleotides. The present calculations predict that the T→A charge-transfer states are not involved in the spectra and excited-state dynamics ofthe A•T oligonucleotides. In addition, the influence of base pairing and stacking on thenature of the 1nΠ* and 1ΠΠ* states are discussed in detail.
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| 23. |
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| 24. |
- Brownstein, Catherine A., et al.
(author)
-
An international effort towards developing standards for best practices in analysis, interpretation and reporting of clinical genome sequencing results in the CLARITY Challenge
- 2014
-
In: Genome Biology. - : Springer Science and Business Media LLC. - 1465-6906 .- 1474-760X. ; 15:3, s. R53-
-
Journal article (peer-reviewed)abstract
- Background: There is tremendous potential for genome sequencing to improve clinical diagnosis and care once it becomes routinely accessible, but this will require formalizing research methods into clinical best practices in the areas of sequence data generation, analysis, interpretation and reporting. The CLARITY Challenge was designed to spur convergence in methods for diagnosing genetic disease starting from clinical case history and genome sequencing data. DNA samples were obtained from three families with heritable genetic disorders and genomic sequence data were donated by sequencing platform vendors. The challenge was to analyze and interpret these data with the goals of identifying disease-causing variants and reporting the findings in a clinically useful format. Participating contestant groups were solicited broadly, and an independent panel of judges evaluated their performance. Results: A total of 30 international groups were engaged. The entries reveal a general convergence of practices on most elements of the analysis and interpretation process. However, even given this commonality of approach, only two groups identified the consensus candidate variants in all disease cases, demonstrating a need for consistent fine-tuning of the generally accepted methods. There was greater diversity of the final clinical report content and in the patient consenting process, demonstrating that these areas require additional exploration and standardization. Conclusions: The CLARITY Challenge provides a comprehensive assessment of current practices for using genome sequencing to diagnose and report genetic diseases. There is remarkable convergence in bioinformatic techniques, but medical interpretation and reporting are areas that require further development by many groups.
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| 25. |
- Cao, Jun, et al.
(author)
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Photoisomerization mechanism of 4-methylpyridine explored by electronic structure calculations and nonadiabatic dynamics simulations
- 2011
-
In: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 134:4, s. 044307-
-
Journal article (peer-reviewed)abstract
- In the present paper, different electronic structure methods have been used to determine stationary and intersection structures on the ground (S-0) and (1)pi pi* (S-2) states of 4-methylpyridine, which is followed by adiabatic and nonadiabatic dynamics simulations to explore the mechanistic photoisomerization of 4-methylpyridine. Photoisomerization starts from the S-2((1)pi pi*) state and overcomes a small barrier, leading to formation of the prefulvene isomer in the S-0 state via a S-2/S-0 conical intersection. The ultrafast S-2 -> S-0 nonradiative decay and low quantum yield for the photoisomerization reaction were well reproduced by the combined electronic structure calculation and dynamics simulation. The prefulvene isomer was assigned as a long-lived intermediate and suggested to isomerize to 4-methylpyridine directly in the previous study, which is not supported by the present calculation. The nonadiabatic dynamics simulation and electronic structure calculation reveal that the prefulvene isomer is a short-lived intermediate and isomerizes to benzvalene form very easily. The benzvalene form was predicted as the stable isomer in the present study and is probably the long-lived intermediate observed experimentally. A consecutive light and thermal isomerization cycle via Dewar isomer was determined and this cycle mechanism is different from that reported in the previous study. It should be pointed out that formation of Dewar isomer from the S-2((1)pi pi*) state is not in competition with the isomerization to the prefulvene form. The Dewar structure observed experimentally may originate from other excited states.
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| 26. |
- Davidsson, Sabina, et al.
(author)
-
Inflammation, Focal Atrophic Lesions, and Prostatic Intraepithelial Neoplasia with Respect to Risk of Lethal Prostate Cancer
- 2011
-
In: Cancer Epidemiology, Biomarkers and Prevention. - : American Association for Cancer Research. - 1055-9965 .- 1538-7755. ; 20:10, s. 2280-2287
-
Journal article (peer-reviewed)abstract
- Background: A challenge in prostate cancer (PCa) management is identifying potentially lethal disease at diagnosis. Inflammation, focal prostatic atrophy, and prostatic intraepithelial neoplasia (PIN) are common in prostate tumor specimens, but it is not clear whether these lesions have prognostic significance. less thanbrgreater than less thanbrgreater thanMethods: We conducted a case-control study nested in a cohort of men diagnosed with stage T1a-b PCa through transurethral resection of the prostate in Sweden. Cases are men who died of PCa (n = 228). Controls are men who survived more than 10 years after PCa diagnosis without metastases (n = 387). Slides were assessed for Gleason grade, inflammation, PIN, and four subtypes of focal prostatic atrophy: simple atrophy (SA), postatrophic hyperplasia (PAH), simple atrophy with cyst formation, and partial atrophy. We estimated OR and 95% CI for odds of lethal PCa with multivariable logistic regression. less thanbrgreater than less thanbrgreater thanResults: Chronic inflammation and PIN were more frequently observed in tumors with PAH, but not SA. No specific type of atrophy or inflammation was significantly associated with lethal PCa overall, but there was a suggestion of a positive association for chronic inflammation. Independent of age, Gleason score, year of diagnosis, inflammation, and atrophy type, men with PIN were 89% more likely to die of PCa (95% CI: 1.04-3.42). less thanbrgreater than less thanbrgreater thanConclusion: Our data show that PIN, and perhaps presence of moderate or severe chronic inflammation, may have prognostic significance for PCa. less thanbrgreater than less thanbrgreater thanImpact: Lesions in tumor adjacent tissue, and not just the tumor itself, may aid in identification of clinically relevant disease.
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| 27. |
- Duan, Sai, et al.
(author)
-
A density functional theory approach to mushroom-like platinum clusters on palladium-shell over Au core nanoparticles for high electrocatalytic activity
- 2011
-
In: Physical Chemistry, Chemical Physics - PCCP. - Cambridge : ROYAL SOC CHEMISTRY. - 1463-9076 .- 1463-9084. ; 13:12, s. 5441-5449
-
Journal article (peer-reviewed)abstract
- Recently, it was found that Pt clusters deposited on Pd shell over Au core nanoparticles (Au@Pd@Pt NPs) exhibit unusually high electrocatalytic activity for the electro-oxidation of formic acid (P. P. Fang, S. Duan, et al., Chem. Sci., 2011, 2, 531-539). In an attempt to offer an explanation, we used here carbon monoxide (CO) as probed molecules, and applied density functional theory (DFT) to simulate the surface Raman spectra of CO at this core-shell-cluster NPs with a two monolayer thickness of Pd shell and various Pt cluster coverage. Our DFT results show that the calculated Pt coverage dependent spectra fit the experimental ones well only if the Pt clusters adopt a mushroom-like structure, while currently the island-like structure is the widely accepted model, which follows the Volmer-Weber growth mode. This result infers that there should be a new growth mode, i.e., the mushroom growth mode as proposed in the present work, for Au@Pd@Pt NPs. We suggest that such a mushroom-like structure may offer novel active sites, which accounts for the observed high electrocatalytic activity of Au@Pd@Pt NPs.
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| 28. |
- Fang, Fang
(author)
-
Epidemiologic studies of amytrophic lateral sclerosis
- 2010
-
Doctoral thesis (other academic/artistic)abstract
- Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disorder characterized by progressive muscular paralysis reflecting degeneration of motor neurons in the primary motor cortex, corticospinal tracts, brainstem and spinal cord. The causes of ALS remain largely unknown more than 140 years after the disease was first described. The overall aims of this thesis were to describe the temporal trend of ALS incidence in Sweden during the recent years and the aggregation of ALS in families, and to investigate potential roles of early life exposure as well as blood lead concentration on the risk of ALS. In Paper I, we described the temporal trend of ALS incidence in Sweden between 1991 and 2005, and demonstrated the incidence variations according to several major demographic factors. We found an approximately 2% annual increase of ALS incidence during the study period. The incidence increased in all age groups except those younger than 50 years. This trend was only significant among people born in Sweden. Compared to those born in April-June, individuals born in October-December were at a slightly higher risk of ALS. In Paper II, we assessed the familial aggregation of ALS in Sweden by comparing the risk of ALS among families of ALS patients to the general Swedish population. We found that the siblings of ALS patients had a 17-fold risk and the children a 9-fold risk of ALS, compared with the reference group. Siblings and children had a greater excess risk if the proband was diagnosed at a younger age, and the excess risk decreased with increasing age at diagnosis of the proband. Co-twins of ALS probands had a relative risk of 32. Spouses of ALS patients had no significantly increased risk. In Paper III, we investigated whether early life exposures, namely, maternal age at delivery and number of siblings, were associated with an altered risk of ALS during 1987-2005 in Sweden. Low maternal age (≤20 years) and high maternal age (≥41 years) were both associated with a higher risk of ALS. The relative risk of ALS increased slightly with increasing number of younger siblings. Children whose first younger sibling was born after the age of 6 years had the greatest relative risk. Exposure to older siblings was not associated with the risk of ALS. In Paper IV, we evaluated the association of blood lead level with ALS risk accounting for bone turnover. We conducted a case-control study including 184 ALS cases identified from the National Registry of Veterans with ALS and 194 veteran controls. Blood lead levels were statistically higher among cases compared to controls. A doubling of blood lead was associated with a 1.9-fold risk of ALS after adjustment for age and bone turnover status. The K59N polymorphism in ALAD gene did not modify the lead-ALS association. In conclusion, by using data from Sweden and the United States, we showed that ALS incidence has been increasing in Sweden, the first-degree relatives of ALS patients have a higher risk of ALS compared to others, and early life exposure (seasonality of birth, maternal age, and exposure to siblings) as well as lead exposure might influence the risk of ALS.
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| 29. |
- Fang, Fang, et al.
(author)
-
Hospitalization for osteoarthritis and prostate cancer specific mortality among Swedish men with prostate cancer
- 2010
-
In: Cancer Epidemiology. - Oxon, United Kingdom : Elsevier BV. - 1877-7821 .- 1877-783X. ; 34:5, s. 644-647
-
Journal article (peer-reviewed)abstract
- Purpose: To examine the potential role of nonsteroidal anti-inflammatory drugs (NSAIDs) use on prostate cancer (PCa) specific mortality. Methods: We studied the association between hospitalization for osteoarthritis prior to PCa diagnosis, as a surrogate for heavy use of NSAIDs, and PCa specific mortality in a large population of PCa patients in Sweden in 1980-2004. Results: Hospitalization for osteoarthritis before PCa diagnosis was associated to a lower PCa specific mortality (hazard ratio [HR], 0.92; 95% confidence interval [CI], 0.88-0.96), but not to the risk of death from other causes (HR, 1.03; 95% Cl, 0.99-1.08). The association was stronger among younger patients and patients diagnosed in earlier calendar years. Conclusions: Our data demonstrate a modestly decreased PCa specific mortality among PCa patients with hospitalization for osteoarthritis prior to PCa diagnosis, compared to those without such experience. This finding lends support to the hypothesis that NSAIDs use may influence PCa progression.
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| 30. |
- Fang, Fang, et al.
(author)
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Immediate risk of suicide and cardiovascular death after a prostate cancer diagnosis : cohort study in the United States
- 2010
-
In: Journal of the National Cancer Institute. - New York, USA : Elsevier. - 0027-8874 .- 1460-2105. ; 102:5, s. 307-14
-
Journal article (peer-reviewed)abstract
- Background: Receiving a cancer diagnosis is a stressful event that may increase risks of suicide and cardiovascular death, especially soon after diagnosis.Methods: We conducted a cohort study of 342,497 patients diagnosed with prostate cancer from January 1, 1979, through December 31, 2004, in the Surveillance, Epidemiology, and End Results Program. Follow-up started from the date of prostate cancer diagnosis to the end of first 12 calendar months after diagnosis. The relative risks of suicide and cardiovascular death were calculated as standardized mortality ratios (SMRs) comparing corresponding incidences among prostate cancer patients with those of the general US male population, with adjustment for age, calendar period, and state of residence. We compared risks in the first year and months after a prostate cancer diagnosis. The analyses were further stratified by calendar period at diagnosis, tumor characteristics, and other variables.Results: During follow-up, 148 men died of suicide (mortality rate = 0.5 per 1000 person-years) and 6845 died of cardiovascular diseases (mortality rate = 21.8 per 1000 person-years). Patients with prostate cancer were at increased risk of suicide during the first year (SMR = 1.4, 95% confidence interval [CI] = 1.2 to 1.6), especially during the first 3 months (SMR = 1.9, 95% CI = 1.4 to 2.6), after diagnosis. The elevated risk was apparent in pre-prostate-specific antigen (PSA) (1979-1986) and peri-PSA (1987-1992) eras but not since PSA testing has been widespread (1993-2004). The risk of cardiovascular death was slightly elevated during the first year (SMR = 1.09, 95% CI = 1.06 to 1.12), with the highest risk in the first month (SMR = 2.05, 95% CI = 1.89 to 2.22), after diagnosis. The first-month risk was statistically significantly elevated during the entire study period, and the risk was higher for patients with metastatic tumors (SMR = 3.22, 95% CI = 2.68 to 3.84) than for those with local or regional tumors (SMR = 1.57, 95% CI = 1.42 to 1.74).Conclusion: A diagnosis of prostate cancer may increase the immediate risks of suicide and cardiovascular death.
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| 31. |
- Fang, Fang, et al.
(author)
-
Maternal bereavement and childhood asthma-analyses in two large samples of Swedish children
- 2011
-
In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 6:11, s. e27202-
-
Journal article (peer-reviewed)abstract
- BACKGROUND: Prenatal factors such as prenatal psychological stress might influence the development of childhood asthma. METHODOLOGY AND PRINCIPAL FINDINGS: We assessed the association between maternal bereavement shortly before and during pregnancy, as a proxy for prenatal stress, and the risk of childhood asthma in the offspring, based on two samples of children 1-4 (n = 426 334) and 7-12 (n = 493 813) years assembled from the Swedish Medical Birth Register. Exposure was maternal bereavement of a close relative from one year before pregnancy to child birth. Asthma event was defined by a hospital contact for asthma or at least two dispenses of inhaled corticosteroids or montelukast. In the younger sample we calculated hazards ratios (HRs) of a first-ever asthma event using Cox models and in the older sample odds ratio (ORs) of an asthma attack during 12 months using logistic regression. Compared to unexposed boys, exposed boys seemed to have a weakly higher risk of first-ever asthma event at 1-4 years (HR: 1.09; 95% confidence interval [CI]: 0.98, 1.22) as well as an asthma attack during 12 months at 7-12 years (OR: 1.10; 95% CI: 0.96, 1.24). No association was suggested for girls. Boys exposed during the second trimester had a significantly higher risk of asthma event at 1-4 years (HR: 1.55; 95% CI: 1.19, 2.02) and asthma attack at 7-12 years if the bereavement was an older child (OR: 1.58; 95% CI: 1.11, 2.25). The associations tended to be stronger if the bereavement was due to a traumatic death compared to natural death, but the difference was not statistically significant. CONCLUSIONS/SIGNIFICANCE: Our results showed some evidence for a positive association between prenatal stress and childhood asthma among boys but not girls.
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| 32. |
- Fang, Fang, et al.
(author)
-
Prediagnostic plasma vitamin D metabolites and mortality among patients with prostate cancer
- 2011
-
In: PLOS ONE. - San Fransisco, USA : Public Library Science. - 1932-6203. ; 6:4
-
Journal article (peer-reviewed)abstract
- Background: Laboratory evidence suggests that vitamin D might influence prostate cancer prognosis.Methodology/principal findings: We examined the associations between prediagnostic plasma levels of 25(OH)vitamin D [25(OH)D] and 1,25(OH)(2) vitamin D [1,25(OH)(2)D] and mortality among 1822 participants of the Health Professionals Follow-up Study and Physicians' Health Study who were diagnosed with prostate cancer. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) of total mortality (n = 595) and lethal prostate cancer (death from prostate cancer or development of bone metastases; n = 202). In models adjusted for age at diagnosis, BMI, physical activity, and smoking, we observed a HR of 1.22 (95% CI: 0.97, 1.54) for total mortality, comparing men in the lowest to the highest quartile of 25(OH)D. There was no association between 1,25(OH)(2)D and total mortality. Men with the lowest 25(OH)D quartile were more likely to die of their cancer (HR: 1.59; 95% CI: 1.06, 2.39) compared to those in the highest quartile (P(trend) = 0.006). This association was largely explained by the association between low 25(OH)D levels and advanced cancer stage and higher Gleason score, suggesting that these variables may mediate the influence of 25(OH)D on prognosis. The association also tended to be stronger among patients with samples collected within five years of cancer diagnosis. 1,25(OH)(2)D levels were not associated with lethal prostate cancer.Conclusions/significance: Although potential bias of less advanced disease due to more screening activity among men with high 25(OH)D levels cannot be ruled out, higher prediagnostic plasma 25(OH)D might be associated with improved prostate cancer prognosis.
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| 33. |
- Fang, Fang, et al.
(author)
-
Right ventricular long-axis response to different chronic loading conditions : Its relevance to clinical symptoms
- 2013
-
In: International Journal of Cardiology. - : Elsevier BV. - 0167-5273 .- 1874-1754. ; 167:2, s. 378-382
-
Journal article (peer-reviewed)abstract
- Background: The intervention timing in atrial septal defect (ASD) or pulmonary valvular stenosis (PVS) is more dependent on symptoms than right ventricular (RV) damage in clinical practice. RV long-axis function is sensitive in revealing RV myocardial dysfunction. We evaluate the impact of different chronic loading conditions on RV long-axis function and its relationship to patients' symptoms in ASD or PVS. Methods: Transthoracic echocardiography was performed in normals (n=39) and patients with isolated secundum ASD (n=45) or PVS (n=38). RV volume- and pressure-overloading were defined as the ratio of RV/left ventricular end-diastolic dimension >= 0.5 and RV systolic pressure >= 40 mm Hg, respectively. RV long-axis dysfunction was defined as M-mode tricuspid annular plane systolic excursion (TAPSE) <1.6 cm. New York Heart Association (NYHA) functional class and other symptoms (decreased exercise tolerance, palpitation and chest pain) were recorded. Results: Thirty-nine (32.0%) had normal loading (Group 1; 39 normals); 24 (19.6%) had isolated volume-overloading (Group 2; all ASDs); 21 (17.2%) had isolated pressure-overloading (Group 3; 21 PVSs) and 38 (31.1%) had both overloading conditions (Group 4; 21 ASDs and 17 PVSs). RV long-axis dysfunction in abnormal loading groups were zero (0%, Group 2), 21 (100%, Group 3) and 22 (57.8%, Group 4) (chi(2)=45.9, p<0.001). Group 3 were more symptomatic (NYHA functional class 2.5 +/- 0.6 versus 1.6 +/- 0.5, p<0.05) and had lower TAPSE (1.6 +/- 0.4 versus 3.0 +/- 0.7 cm, p<0.05) than Group 2. RV long-axis dysfunction was the strongest predictor of the presence of symptoms (odds ratio=9.298, p<0.001). Conclusion: Chronic volume-overloading accentuates while pressure-overloading attenuates RV long-axis excursion and its impairment was associated with the presence of symptoms.
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| 34. |
- Fang, Fang, et al.
(author)
-
Risk of infection-related cancers after the loss of a child : a follow-up study in Sweden
- 2011
-
In: Cancer Research. - Philadelphia, USA : American Association for Cancer Research. - 0008-5472 .- 1538-7445. ; 71:1, s. 116-22
-
Journal article (peer-reviewed)abstract
- It is unknown whether severe emotional stress due to loss of a child influences the risk of cancers susceptible to immune modulation such as infection-related cancers. We conducted a historic cohort study in 1990 to 2004 on the basis of the Swedish Multi-Generation Register including 4,687,073 parents. Death of a child was identified through the Causes of Death Register. Poisson regression was used to derive the relative risks (RR) and 95% confidence intervals (CI) of infection-related cancers, comparing the incidence rates of parents who lost a child with those who never lost a child. A total of 101,306 parents (2%) had lost a child during follow-up, among whom 1,608 subsequently developed infection-related cancers. After adjustment for age, sex, calendar year, educational level, and civil status, the overall RR of 14 cancers studied was 1.07 (95% CI: 1.02-1.12). Parents who lost a child were particularly at a higher risk for cancers potentially associated with human papilloma virus (HPV) infection such as cervical cancer (RR: 1.46; 95% CI: 1.17-1.80). Higher RRs for most cancers were obtained within 5 years after child loss and excess risk for liver and stomach cancers was confined to that period. No association was observed for lymphoma and nonmelanoma skin cancer at any time point after child loss. Although potential confounding by unmeasured factors cannot be ruled out, our findings lend support to the hypothesis that severe life stressors, such as child loss, may raise the risk for several, chiefly HPV-related, cancers.
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| 35. |
- Fang, Fang, et al.
(author)
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Suicide and cardiovascular death after a cancer diagnosis
- 2012
-
In: New England Journal of Medicine. - Walton, USA : Massachusetts Medical Society. - 0028-4793 .- 1533-4406. ; 366:14, s. 1310-1318
-
Journal article (peer-reviewed)abstract
- Background: Receiving a diagnosis of cancer is a traumatic experience that may trigger immediate adverse health consequences beyond the effects of the disease or treatment.Methods: Using Poisson and negative binomial regression models, we conducted a historical cohort study involving 6,073,240 Swedes to examine the associations between a cancer diagnosis and the immediate risk of suicide or death from cardiovascular causes from 1991 through 2006. To adjust for unmeasured confounders, we also performed a nested, self-matched case-crossover analysis among all patients with cancer who died from suicide or cardiovascular diseases in the cohort.Results: As compared with cancer-free persons, the relative risk of suicide among patients receiving a cancer diagnosis was 12.6 (95% confidence interval [CI], 8.6 to 17.8) during the first week (29 patients; incidence rate, 2.50 per 1000 person-years) and 3.1 (95% CI, 2.7 to 3.5) during the first year (260 patients; incidence rate, 0.60 per 1000 person-years). The relative risk of cardiovascular death after diagnosis was 5.6 (95% CI, 5.2 to 5.9) during the first week (1318 patients; incidence rate, 116.80 per 1000 person-years) and 3.3 (95% CI, 3.1 to 3.4) during the first 4 weeks (2641 patients; incidence rate, 65.81 per 1000 person-years). The risk elevations decreased rapidly during the first year after diagnosis. Increased risk was particularly prominent for cancers with a poor prognosis. The case-crossover analysis largely confirmed results from the main analysis.Conclusions: In this large cohort study, patients who had recently received a cancer diagnosis had increased risks of both suicide and death from cardiovascular causes, as compared with cancer-free persons. (Funded by the Swedish Council for Working Life and Social Research and others.).
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| 36. |
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| 37. |
- Fang, Qiu, et al.
(author)
-
The Conical Intersection Dominates the Generation of Tropospheric Hydroxyl Radicals from NO2 and H2O
- 2010
-
In: Journal of Physical Chemistry A. - : American Chemical Society (ACS). - 1089-5639 .- 1520-5215. ; 114:13, s. 4601-4608
-
Journal article (peer-reviewed)abstract
- In the present work, we report a quantitative understanding on how to generate hydroxyl radicals from NO2 and H2O in the troposphere upon photoexcitation at 410 nm by using multiconfigurational perturbation theory and density functional theory. The conical intersections dominate the nonadiabatic relaxation processes after NO2 irradiated at similar to 410 nm in the troposphere and further control the generation of OH radical by means of hydrogen abstraction. In agreement with two-component fluorescence observed by laser techniques, there are two different photophysical relaxation channels along decreasing and increasing O-N-O angle of NO2. In the former case, the conical intersection between (B) over tilde B-2(1) and (A) over tilde B-2(2) (CI (B-2(2)/B-2(1)) first funnels NO2 out of the Franck-Condon region of (B) over tilde B-2(1) and relaxes to the (A) over tilde B-2(2) surface. Following the primary relaxation, the conical intersection between (A) over tilde B-2(2) and (X) over tilde (2)A(1) (CI(B-2(2)/(2)A(1))) drives NO2 to decay into highly vibrationally excited (X) over tilde (2)A(1) state that is more than 20 000 cm(-1) above zeroth-order vertical bar n(1),n(2),n(3) = 0 > vibrational level. In the latter case, increasing the O-N-O angle leads NO2 to relax to a minimum of (B) over tilde B-2(1) with a linear O-N-O arrangement. This minimum point is also funnel region between (B) over tilde B-2(1) and (X) over tilde (2)A(1) (CI(B-2(1)/(2)A(1))) and leads NO2 to relax into a highly vibrationally excited (X) over tilde (2)A(1) state. The high energetic level of vibrationally excited state has enough energy to overcome the barrier of hydrogen abstraction (40-50 kcal/mol) from water vapor, producing OH ((2)Pi(3/2)) radicals. The collision between NO2 and H2O molecules not only is a precondition of hydrogen abstraction but induces the faster internal conversion (CIIC) via conical intersections. The faster internal conversion favors more energy transfer from electronically excited states into highly vibrationally excited (X) over tilde (2)A(1) states. The collision (i.e., the heat motion of molecules) functions as the trigger and accelerator in the generation of OH radicals from NO2 and H2O in the troposphere.
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| 38. |
- Huang, Jiaqi, et al.
(author)
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Pancreatic cancer risk after loss of a child : a register-based study in Sweden during 1991-2009
- 2013
-
In: American Journal of Epidemiology. - : Oxford University Press (OUP). - 0002-9262 .- 1476-6256. ; 178:4, s. 582-589
-
Journal article (peer-reviewed)abstract
- The potential role of psychological stress in pancreatic cancer has rarely been investigated in epidemiologic studies. During 1991-2009, we conducted a nested case-control study based on Swedish national population and health registers to investigate whether severe psychological stress induced by the death of a child was associated with subsequent risk of pancreatic cancer. The study included 16,522 cases and 82,107 controls who were matched to the cases on sex and year of birth. Conditional logistic regression was used to estimate odds ratios and 95% confidence intervals. Overall, loss of a child was associated with an odds ratio of 1.09 for pancreatic cancer (95% confidence interval (CI): 1.02, 1.17). The risk elevation was mainly seen during the first 5 years after the loss (odds ratio (OR) = 1.27, 95% CI: 1.12, 1.45) and for loss of a child due to suicide (OR = 1.23, 95% CI: 1.03, 1.46). The association was statistically significant among women but not among men, and it appeared stronger for early-onset pancreatic cancer. Persons with a history of psychiatric illness had the greatest risk increase after child loss (OR = 1.43, 95% CI: 1.17, 1.76). Although other explanations are possible, our findings provide some evidence that psychological stress may be associated with pancreatic cancer.
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| 39. |
- Kennedy, Beatrice, 1982-, et al.
(author)
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Loss of a parent and the risk of cancer in early life : a nationwide cohort study
- 2014
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In: Cancer Causes and Control. - Dordrecht, Netherlands : Springer. - 0957-5243 .- 1573-7225. ; 25:4, s. 499-506
-
Journal article (peer-reviewed)abstract
- Background: While early-life exposure to stress has been associated with subsequent psychiatric and cardiovascular morbidity, little is known regarding its potential role in cancer development. We hypothesized that severe emotional stress, such as the loss of a parent through death during childhood, may increase the risk of cancer in early life.Method: Based on the Swedish Multi-Generation Register, we identified a cohort of 4,219,691 individuals who had both parents identifiable in the same register and followed the cohort from birth to the age of 40 years between 1961 and 2006. Through information retrieved from the Swedish Causes of Death and Cancer Registers, we ascertained death among the parents and cancer diagnosis among the cohort individuals. We used Poisson regression to calculate the relative risks (RRs) and 95 % confidence intervals (CIs).Results: Parental death was not associated with total cancer risk. However, parental death during childhood was associated with a higher risk of human papillomavirus (HPV) infection-related cancers (RR 1.4; 95 % CI 1.2-1.7), and loss during early adulthood (>18 years) entailed a higher risk of cancers of the stomach (RR 1.8; 95 % CI 1.3-2.6), lung (RR 1.7; 95 % CI 1.1-2.4), rectum (RR 1.4; 95 % CI 1.0-2.0), and breast (RR 1.1; 95 % CI 1.0-1.3). A significant association was observed for pancreatic cancer for both loss during childhood (RR 2.6; 95 % CI 1.6-4.2) and afterward (RR 2.8; 95 % CI 1.9-4.3).Conclusion: Our results suggest that severe psychological stress in early life may be associated with premature development of certain malignancies, particularly cancers related to smoking and HPV infection.
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| 40. |
- Liao, Te-Yu, et al.
(author)
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Phylogenetic analysis of the genus Rasbora (Teleostei: Cyprinidae)
- 2010
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In: Zoologica Scripta. - : Wiley. - 0300-3256 .- 1463-6409. ; 39:2, s. 155-176
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Journal article (peer-reviewed)abstract
- A phylogenetic analysis was conducted based on 35 cyprinid taxa, including 29 species of Rasbora, and 41 morphological characters. A strict consensus tree from four equally parsimonious trees recovered rasborins as a monophyletic group characterized by (i) presence of dark supra-anal pigment and subpeduncular streak, (ii) 5–6 branched anal-fin rays, (iii) dorsal-fin insertion 1–3 scales behind pelvic-fin insertion, (iv) lateral process of second vertebra more or less straight, (v) 1–5 more abdominal than caudal vertebrae, (vi) absence of foramen in anterior wall of horizontal limb of the cleithrum, (vii) presence of rasborin process on epibranchial 4, and (viii) interhyal well ossified. Rasbora sensu stricto can be distinguished from all other rasborin genera by the presence of an opercular canal. Four new genera, viz. Brevibora, n. gen., Kottelatia, n, gen., Rasbosoma, n. gen. and Trigonopoma, n. gen., are recognized and described.
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| 41. |
- Liao, Te-Yu, et al.
(author)
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Phylogenetic position of rasborin cyprinids and monophyly of major lineages among the Danioninae, based on morphological characters (Cypriniformes : Cyprinidae)
- 2011
-
In: Journal of Zoological Systematics and Evolutionary Research. - : Hindawi Limited. - 0947-5745 .- 1439-0469. ; 49:3, s. 224-232
-
Journal article (peer-reviewed)abstract
- The cyprinid subfamily Danioninae is one of the most important fish groups due to its inclusion of the model fish, Danio rerio. Molecular investigations have shown that species traditionally placed in the Danioninae are non-monophyletic, divided into two groups corresponding to the Danioninae and Opsariichthyinae. The Danioninae are further divided into three lineages, i.e. chedrins, danionins and rasborins. However, morphological characters determining the foregoing groups are unknown. To investigate the interrelationships among major lineages within the Danioninae, a phylogenetic analysis based on 43 morphological characters from 34 taxa was conducted. Parsimony analysis recovers the Danioninae and Opsariichthyinae to be distinguished by the Y-shaped ligament, absent in the Danioninae while present in the Opsariichthyinae. The Danioninae are divided into two tribes, Danionini and Rasborini. The Rasborini, including Boraras, Brevibora, Horadandia, Kottelatia, Rasbora, Rasboroides, Rasbosoma, Trigonopoma and Trigonostigma, are diagnosed by presence of dark supra-anal pigment and subpeduncular streak as well as presence of the rasborin process on epibranchial 4. The Danionini are composed of two subtribes, Danionina and Chedrina, the Danionina including Chela, Danio, Devario, Microdevario and Microrasbora, and the Chedrina comprising Chelaethiops, Esomus, Luciosoma, Megarasbora, Mesobola, Nematabramis, Opsarius, Raiamas and Salmophasia. The Danionina are diagnosed by the unossified interhyal and presence of the danionin foramen in the horizontal limb of the cleithrum while the Chedrina are characterized by the postcleithrum absent or greatly reduced and approximately normal to abdominal ribs when present.
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| 42. |
- Pramod, P.K., et al.
(author)
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Betadevario ramachandrani, a new danionine genus and species from the Western Ghats of India (Teleostei: Cyprinidae: Danioninae)
- 2010
-
In: Zootaxa. - 1175-5326 .- 1175-5334. ; 2519, s. 31-47
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Journal article (peer-reviewed)abstract
- Betadevario, new genus, with the single species B. ramachandrani, new species, from Karnataka, southwestern India, is closely related to Devario but differs from it in having two pairs of long barbels (vs. two pairs of short or rudimentary barbels, or barbels absent), wider cleithral spot which extends to cover three scales horizontally (vs. covering only one scale in width), long and low laminar preorbital process (vs. absent or a slender pointed spine-like process) along the anterior margin of the orbit, a unique flank colour pattern with a wide dark band along the lower side, bordered dorsally by a wide light stripe (vs. vertical bars, or stripes narrow and usually in greater number).
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| 43. |
- Vidarsdottir, Halldora, et al.
(author)
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Spousal loss and cognitive function in later life : a 25-year follow-up in the AGES-Reykjavik study
- 2014
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In: American Journal of Epidemiology. - Cary, USA : Oxford University Press. - 0002-9262 .- 1476-6256. ; 179:6, s. 674-83
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Journal article (peer-reviewed)abstract
- The aim of this study was to investigate the associations between loss of a life partner and the development of dementia and decline in cognitive function in later life. We used an Icelandic cohort of 4,370 participants in the Age, Gene/Environment Susceptibility-Reykjavik Study who were living as married in 1978 (born in 1907-1935) and were either still married (unexposed cohort) or widowed (exposed cohort) at follow-up (in 2002-2006). We ascertained history of marital status and spouse's death by record linkage to the Registry of the Total Population, Statistics Iceland. The outcome measures were as follows: 1) dementia and mild cognitive impairment; and 2) memory, speed of processing, and executive function. During the observation period, 3,007 individuals remained married and 1,363 lost a spouse through death. We did not find any significant associations between loss of a spouse and our outcome variables, except that widowed women had poorer executive function (mean = -0.08) during the first 2 years after their husbands' deaths compared with still-married women (mean = 0.09). Our findings do not support the notion that the risk of dementia is increased following the loss of a spouse, yet women demonstrate a seemingly temporary decline in executive function following the death of a partner.
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| 44. |
- Wu, Ming-Chung, et al.
(author)
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Nitrogen-doped anatase nanofibers decorated with noble metal nanoparticles for photocatalytic production of hydrogen
- 2011
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In: ACS NANO. - : American Chemical Society. - 1936-0851 .- 1936-086X. ; 5:6, s. 5025-5030
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Journal article (peer-reviewed)abstract
- We report the synthesis of N-doped TiO2 nanofibers and high photocatalytic efficiency in generating hydrogen from ethanol-water mixtures under UV-A and UV-B irradiation. Titanate nanofibers synthesized by hydrothermal method are annealed in air and/or ammonia to achieve N-doped anatase fibers. Depending on the synthesis route, either interstitial N atoms or new N-Ti bonds appear in the lattice resulting in slight lattice expansion as shown by XPS and HR-TEM analyses, respectively. These nanofibers were then used as support for Pd and Pt nanoparticles deposited with wet impregnation followed by calcination and reduction. In the hydrogen generation tests the N-doped samples were clearly outperforming their un-doped counterparts showing remarkable efficiency not only under UV-B but also with UV-A illumination. Applying 100 mg catalyst (N-doped TiO2 nanofiber decorated with Pt nanoparticles) in 1 L water-ethanol mixture the H2 evolution rates were as high as 700 μmol/h (UV-A) and 2250 μmol/h (UV-B) corresponding to photo energy percentages of ~3.6% and ~12.3%, respectively.
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| 45. |
- Wu, Ming-Chung, et al.
(author)
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Photo-Kelvin probe force microscopy for photocatalytic performance characterization of single filament of TiO2 nanofiber photocatalysts
- 2013
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In: Journal of Materials Chemistry A. - : Royal Society of Chemistry (RSC). - 2050-7488 .- 2050-7496. ; 1:18, s. 5715-5720
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Journal article (peer-reviewed)abstract
- This is an in-depth study on the photocatalytic performance characterization for single filament of TiO2 nanofiber photocatalysts by the novel photo-Kelvin probe force microscopy technique (photo-KPFM) and first principles calculations. Three kinds of TiO2 nanofibers: anatase TiO2 nanofibers (anatase TiO2 NFs), nitrogen doped TiO2 nanofibers (N-TiO2 NFs), and nitrogen doped TiO2 nanofibers decorated with platinum nanoparticles (N-TiO2-Pt NFs) were investigated. The N-TiO2-Pt NFs exhibit the largest negative photo surface potential shift (-182 mV) as compared to anatase TiO2 NFs (-29 mV). The first-principles calculations based on density functional theory (CASTEP simulation software) indicate that the significant photo surface potential shift obtained by adding nitrogen and platinum into TiO2 NFs is induced by two mechanisms: (1) enhancement in absorbance to increase exciton generation and (2) decreased charge recombination to increase surface charge. These changes in the photo surface potential of various TiO2 nanofibers are closely correlated with their photocatalytic activity. Thus, this novel photo-KPFM provides a useful technique to easily monitor the photocatalytic capability of materials in the development of high performance photocatalysts.
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| 46. |
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| 47. |
- Zhang, Yinping, et al.
(author)
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Ten cities cross-sectional questionnaire survey of children asthma and other allergies in China
- 2013
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In: Chinese Science Bulletin. - : Springer Science and Business Media LLC. - 1001-6538 .- 1861-9541. ; 58:34, s. 4182-4189
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Journal article (peer-reviewed)abstract
- Asthma, rhinitis and eczema (allergic or non-allergic) have increased throughout the world during the last decades, especially among children. Changes in the indoor environment are suspected to be important causes. China has experienced a dramatic change in indoor environmental exposures during the past two decades. However, such changes and their associations with children's asthma and other health aspects have not been thoroughly studied. China, Children, Homes, Health (CCHH), Phase I, was a cross-sectional questionnaire survey of 48219 children 1-8 years old in 10 Chinese cities during 2010-2012. The questionnaire includes the International Study of Asthma and Allergies in Childhood (ISAAC) core health questions and additional questions regarding housing, life habits and outdoor environment. In health analyses, children aged 3-6 years old were included. The prevalences of doctor diagnosed asthma varied from 1.7% to 9.8% (mean 6.8%), a large increase from 0.91% in 1999 and 1.50% in 2000. The prevalence of wheeze, rhinitis and atopic eczema (last 12 months) varied from 13.9% to 23.7%, 24.0% to 50.8% and 4.8% to 15.8%, respectively. Taiyuan had the lowest prevalences of all illnesses and Shanghai the highest, except for wheezewhere the highest value was for Urumqi. We found (1) no obvious association between disease prevalences and ambient PM10 concentrations and (2) higher prevalences of disease in humid climates with hot summers and cold winters, but with no centrally heated buildings. Associations between the diseases and economic status as indexed by Gross Domestic Product (GDP) requires further study.
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