45,722 research outputs found
Study of the decay mechanism for B+ -> p(p)over-barK(+) and B+ -> p(p)over-bar pi(+)
No full textWe study the characteristics of the low mass p (p) over bar enhancements near threshold in the three-body decays B+ -> p (p) over barK(+) and B+ -> p (p) over bar pi(+). We observe that the proton polar angle distributions in the p (p) over bar helicity frame in the two decays have the opposite polarity, and measure the forward-backward asymmetries as a function of the p mass for the p (p) over barK(+) mode. We also search for the intermediate two-body decays, B+ -> (p) over bar Delta(++) and B+ -> p (Delta) over bar (0), and set upper limits on their branching fractions. These results are obtained from a 414 fb(-1) data sample that contains 449 x 10(6) B (B) over bar events collected near the Gamma(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. (c) 2007 Elsevier B.V. All rights reserved.IPE
Regional differences in effects of APOE epsilon4 on cognitive impairment in non-demented subjects
No full textItem does not contain fulltextBACKGROUND: The APOE epsilon4 allele is a risk factor for Alzheimer's disease (AD). APOE epsilon4 is common in non-demented subjects with cognitive impairment. In both healthy people and people with AD, its prevalence has a north-south gradient across Europe. In the present study, we investigated whether the relation between the APOE epsilon4 allele and cognitive impairment varied across Northern, Middle and Southern Europe. We also investigated whether a north-south gradient existed in subjects with subjective cognitive impairment (SCI), amnestic mild cognitive impairment (MCI) and non-amnestic MCI. METHODS: Data from 16 centers across Europe were analyzed. RESULTS: A north-south gradient in APOE epsilon4 prevalence existed in the total sample (62.7% for APOE epsilon4 carriers in the northern region, 42.1% in the middle region, and 31.5% in the southern region) and in subjects with SCI and amnestic MCI separately. Only in Middle Europe was the APOE epsilon4 allele significantly associated with poor performance on tests of delayed recall and learning, as well as with the amnestic subtype of MCI. CONCLUSION: The APOE epsilon4 allele frequencies in subjects with SCI and amnestic MCI have a north-south gradient. The relation between the APOE epsilon4 allele and cognition is region dependent
Measurement of the CKM angle gamma from a combination of B->Dh analyses
No full textA combination of three LHCb measurements of the CKM angle gamma is presented. The decays B->DK and B->Dpi are used, where D denotes an admixture of D0 and D0-bar mesons, decaying into K+K-, pi+pi-, K+-pi-+, K+-pi-+pi+-pi-+, KSpi+pi-, or KSK+K- final states. All measurements use a dataset corresponding to 1.0 fb-1 of integrated luminosity. Combining results from B->DK decays alone a best-fit value of gamma = 72.0 deg is found, and confidence intervals are set gamma in [56.4,86.7] deg at 68% CL, gamma in [42.6,99.6] deg at 95% CL. The best-fit value of gamma found from a combination of results from B->Dpi decays alone, is gamma = 18.9 deg, and the confidence intervals gamma in [7.4,99.2] deg or [167.9,176.4] deg at 68% CL, are set, without constraint at 95% CL. The combination of results from B->DK and B->Dpi decays gives a best-fit value of gamma = 72.6 deg and the confidence intervals gamma in [55.4,82.3] deg at 68% CL, gamma in [40.2,92.7] deg at 95% CL are set. All values are expressed modulo 180 deg, and are obtained taking into account the effect of D0-D0bar mixing
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Measurement of the ratio of branching fractions B(B0→K∗0γ )/B(B0s→φγ ) and the directCP asymmetry inB 0→K∗0γ
No full textThe ratio of branching fractions of the radiative B decays B0→K⁎0γ and B0s→ϕγ has been measured using an integrated luminosity of 1.0 fb−1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of s√=7TeV. The value obtained is
B(B0→K⁎0γ)B(B0s→ϕγ)=1.23±0.06(stat.)±0.04(syst.)±0.10(fs/fd),
where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for B(B0→K⁎0γ), the branching fraction B(B0s→ϕγ) is measured to be (3.5±0.4)×10−5.
The direct CP asymmetry in B0→K⁎0γ decays has also been measured with the same data and found to be
ACP(B0→K⁎0γ)=(0.8±1.7(stat.)±0.9(syst.))%.
Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations
Inquiry into the interlocution of students engaged with mathematics: appreciating links between research and practice
No full textFor either to be useful, links between research and practice are critical. Just as important are connections between the practice of students engaged in mathematical activity and research that seeks to understand that practice. This research report explores lessons that researchers and practitioners can learn from an inquiry into the interlocution of students working collaboratively in small groups when engaged in talking and listening to each other. We use the term interlocution to denote discursive practices of learners in conversational exchanges. Questions that motivate this research included the following. What discursive practices do interlocutors employ as they work collaboratively to understand and resolve mathematical tasks? How do these practices influence the growth of their mathematical ideas? In what ways do their discursive practices help them move from a contextualized, situated task to generalize the task or their solution? Do students' discursive practices assist them to connect and generalize ideas from a new problem to others on which they have worked?Powell, A. B., & Maher, C. A. (2002). Inquiry into the interlocution of students engaged with mathematics: Appreciating links between research and practice. In D.S. Mewborn, P. Sztajn, D.Y. White, H.G. Wiegel, R.L. Bryant & K. Nooney (Eds.), Proceedings of the twenty-fourth annual meeting of the North American Chapter of the International Group for the Psychology of Mathematics Education (Athens, Georgia) (Vol. 1, pp. 317-329). Columbus, OH: ERIC Clearinghouse for Science, Mathematics, and Environmental Education
Branching fraction and CP asymmetry of the decays B+→K0Sπ+ and B+→K0SK+
No full textAn analysis of B+ → K0
Sπ+ and B+ → K0
S K+ decays is performed with the LHCb experiment. The pp
collision data used correspond to integrated luminosities of 1 fb−1 and 2 fb−1 collected at centre-ofmass
energies of
√
s = 7 TeV and
√
s = 8 TeV, respectively. The ratio of branching fractions and the
direct CP asymmetries are measured to be B(B+ → K0
S K+
)/B(B+ → K0
Sπ+
) = 0.064 ± 0.009 (stat.) ±
0.004 (syst.), ACP(B+ → K0
Sπ+
) = −0.022 ± 0.025 (stat.) ± 0.010 (syst.) and ACP(B+ → K0
S K+
) =
−0.21 ± 0.14 (stat.) ± 0.01 (syst.). The data sample taken at
√
s = 7 TeV is used to search for
B+
c
→ K0
S K+ decays and results in the upper limit ( fc · B(B+
c
→ K0
S K+
))/( fu · B(B+ → K0
Sπ+
)) <
5.8 × 10−2 at 90% confidence level, where fc and fu denote the hadronisation fractions of a ¯b
quark
into a B+
c or a B+ meson, respectively
Measurement of the branching fraction
No full textThe B
0
s
→ J/ψK
0
S
branching fraction is measured in a data sample corresponding to 0.41 fb−1
of integrated luminosity collected with the LHCb detector at the LHC. This channel is sensitive to
the penguin contributions affecting the sin 2β measurement from B
0
→ J/ψK
0
S
. The time-integrated
branching fraction is measured to be B(B
0
s
→ J/ψK
0
S
) = (1.83±0.28)×10−5
. This is the most precise
measurement to date
(A,B) Western blot analysis of total and phospho-Bsk protein (p-Bsk) in S2 cells treated with LPS for the indicated periods
No full textLysates were probed with anti-p-JNK (A) and anti-JNK (B) antibodies on a single blot. The primary antibodies were detected with Alexa-fluor 680 and Alexa-fluor 750-labeled secondary antibodies, respectively. Panels A and B are false-colored and merged in C, with total Bsk in red and p-Bsk in green. Molecular mass markers are shown in lane 9. (D) p-Bsk protein levels in (A) were quantified and normalized relative to total JNK protein levels in (B) for each time point. The p-JNK:total JNK ratio at 0min LPS exposure was assigned a value of one and all other ratios are shown relative to this value. Treatment of S2 cells with LPS led to a transitory phosphorylation of Bsk with maximal Bsk phosphorylation at 5 mins. <p><b>Copyright information:</b></p><p>Taken from "Quantitative Evaluation of Signaling Events in Drosophila S2 Cells"</p><p></p><p>Biological Procedures Online 2008;10():20-28.</p><p>Published online Jan 2008</p><p>PMCID:PMC2275046.</p><p>Article © by the author(s). This paper is Open Access and is published in Biological Procedures Online under license from the author(s). Copying, printing, redistribution and storage permitted. Journal © 1997-2008 Biological Procedures Online.</p
Malacoceros jennicus Graff, Blake & Wishner 2008
No full text<i>Malacoceros jennicus</i> Graff, Blake & Wishner, 2008 <p> <i>Malacoceros jennicus</i> Graff, Blake & Wishner, 2008: 925 –939, figs 1–2.</p> <p> <b>Type locality.</b> Kick´em Jenny, hydrothermally active submarine volcano in Lesser Antilles Arc, Caribbean (12º18.076´N, 61º 38.256W), 262 m.</p> <p> <b>Type material.</b> Holotype (USNM 1086647), paratypes (USNM 1086649). <b>Records.</b> Only known from type locality.</p>Published as part of <i>Delgado-Blas, Victor Hugo & Salazar-Silva, Patricia, 2011, Taxonomic catalogue of the Spionidae (Annelida: Polychaeta) of the Grand Caribbean, pp. 39-66 in Zootaxa 2782</i> on page 47, DOI: <a href="http://zenodo.org/record/206833">10.5281/zenodo.206833</a>
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