59,881 research outputs found
Measurement of the ratio of prompt χ c to J / ψ production in pp collisions at √s = 7 TeV
The prompt production of charmonium χ c and J / ψ states is studied in proton-proton collisions at a centre-of-mass energy of √s = 7 TeV at the Large Hadron Collider. The χ c and J / ψ mesons are identified through their decays χ c → J / ψ γ and J / ψ → μ + μ - using 36 pb - 1 of data collected by the LHCb detector in 2010. The ratio of the prompt production cross-sections for χ c and J / ψ, σ (χ c → J / ψ γ) / σ (J / ψ), is determined as a function of the J / ψ transverse momentum in the range 2 < p T J / ψ < 15 GeV / c. The results are in excellent agreement with next-to-leading order non-relativistic expectations and show a significant discrepancy compared with the colour singlet model prediction at leading order, especially in the low p T J / ψ region
[bust portrait of Ambrose Topping].
Photo Div C.3 .Schmidt Brewery.8. Bust portrait of Ambrose Topping. Man associated with the Schmidt Brewery.; Handwritten on verso, "Ambrose Topping."; Includes 28 bust portraits of men associated with the Schmidt Brewery in Philadelphia. Subjects include: Edward A. Schmidt; J. Fred Betz, Jr.; Joseph Geiger; John Gardiner, Jr.; Ambrose Topping; John Gardiner; Adam Scheidt; Peter Schemm; George Weisbrod; Fred Poth; John Rohem; Albert Baltz; Jules Nachod; Bartholomew Bergdoll; Louis Bergdoll; Harr Poth; Gustavus W. Bergner; Ludwig Prospect; John Rothacker. Also includes 1 reproduction of a lithograph advertisement for the Engel & Wolf Brewery, Fountain Green, Philadelphia, by Augustus Kollner
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
First evidence of the B 0 → J / ψ ω decay is found and the B s 0 → J / ψ η and B s 0 → J / ψ η ′ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb -1 collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV. The branching fractions of these decays are measured relative to that of the B 0 → J / ψ ρ 0 decay:frac(B (B 0 → J / ψ ω), B (B 0 → J / ψ ρ 0)) = 0.89 ± 0.19 (stat) - 0.13 + 0.07 (syst),frac(B (B s 0 → J / ψ η), B (B 0 → J / ψ ρ 0)) = 14.0 ± 1.2 (stat) - 1.5 + 1.1 (syst) - 1.0 + 1.1 (frac(f d, f s)),frac(B (B s 0 → J / ψ η ′), B (B 0 → J / ψ ρ 0)) = 12.7 ± 1.1 (stat) - 1.3 + 0.5 (syst) - 0.9 + 1.0 (frac(f d, f s)), where the last uncertainty is due to the knowledge of f d / f s, the ratio of b-quark hadronization factors that accounts for the different production rate of B 0 and B s 0 mesons. The ratio of the branching fractions of B s 0 → J / ψ η ′ and B s 0 → J / ψ η decays is measured to befrac(B (B s 0 → J / ψ η ′), B (B s 0 → J / ψ η)) = 0.90 ± 0.09 (stat) - 0.02 + 0.06 (syst)
Morphology and genesis of slow-spreading ridges - seabed scattering and seismic imaging within the ocean crust
A grid of 32 across-axis and five axis-parallel multichannel seismic (MCS) reflection profiles were acquired at an axial volcanic ridge (AVR) segment at 57° 45'N, 32° 35'W on the slow-spreading Reykjanes Ridge, Mid-Atlantic Ridge, to determine the along-axis variation and geometry of the axial magmatic system and to investigate the relationship between magma chamber structure, the along-axis continuity and segmentation of melt supply to the crust, the development of faulting and the thickness of oceanic layer 2A.Seismic reflection profiles acquired at mid-ocean ridges are prone to being swamped by high amplitude seabed scattered noise which can either mask or be mistaken for intracrustal reflection events. In this paper, we present the results of two approaches to this problem which simulate seabed scatter and which can either be used to remove or simply predict events within processed MCS profiles.The 37 MCS profiles show clear intracrustal seismic events which are related to the structure of oceanic layer 2, to the axial magmatic system and to the faults which dismember each AVR as it ages through its tectono-magmatic life cycle and which form the median valley walls. The layer 2A event can be mapped around the entirety of the survey area between 0.1 and 0.5 s two-way traveltime below the seabed, being thickest at AVR centres, and thinning both off-axis and along-axis towards AVR tips. Both AVR-parallel and ridge-parallel trends are observed, with the pattern of on-axis layer 2A thickness variation preserved beneath relict AVRs which are rafted off-axis largely intact.Each active AVR is underlain by a mid-crustal melt lens reflection extending almost along its entire length. Similar reflection events are observed beneath the offset basins between adjacent AVRs. These are interpreted as new AVRs at the start of their life cycle, developing centrally within the median valley. The east–west spacings of relict AVRs and offset basins is 5–7 km, corresponding to a life span of the order of 0.5–0.7 Myr, during which AVRs appear to undergo multiple 20–60 Kyr tectono-magmatic cycles.<br/
Measurement of the time-dependent CP asymmetry in B0 -> J/ψ KS0 decays
This Letter reports a measurement of the CP violation observables SJ/ψK0S and CJ/ψK0S in the decay channel B0→J/ψK0S performed with 1.0 fb−1 of pp collisions at s√=7 TeV collected by the LHCb experiment. The fit to the data yields SJ/ψK0S=0.73±0.07(stat)±0.04(syst) and CJ/ψK0S=0.03±0.09(stat)±0.01(syst). Both values are consistent with the current world averages and within
expectations from the Standard Model
Letter from J. E. Gavin to Louis C. Cramton regarding Sale of Bright Angel Trail
Letter from J. E. Gavin to Louis C. Cramton regarding the Bright Angel Trail controversy, including newspaper clipping
Assessment of survival and mortality factors in field populations of beneficial arthropods
Acute Ethanol Administration Rapidly Increases Phosphorylation of Conventional Protein Kinase C in Specific Mammalian Brain Regions in Vivo
Background
Protein kinase C (PKC) is a family of isoenzymes that regulate a variety of functions in the central nervous system including neurotransmitter release, ion channel activity, and cell differentiation. Growing evidence suggests that specific isoforms of PKC influence a variety of behavioral, biochemical, and physiological effects of ethanol in mammals. The purpose of this study was to determine whether acute ethanol exposure alters phosphorylation of conventional PKC isoforms at a threonine 674 (p-cPKC) site in the hydrophobic domain of the kinase, which is required for its catalytic activity.
Methods
Male rats were administered a dose range of ethanol (0, 0.5, 1, or 2 g/kg, intragastric) and brain tissue was removed 10 minutes later for evaluation of changes in p-cPKC expression using immunohistochemistry and Western blot methods.
Results
Immunohistochemical data show that the highest dose of ethanol (2 g/kg) rapidly increases p-cPKC immunoreactivity specifically in the nucleus accumbens (core and shell), lateral septum, and hippocampus (CA3 and dentate gyrus). Western blot analysis further showed that ethanol (2 g/kg) increased p-cPKC expression in the P2 membrane fraction of tissue from the nucleus accumbens and hippocampus. Although p-cPKC was expressed in numerous other brain regions, including the caudate nucleus, amygdala, and cortex, no changes were observed in response to acute ethanol. Total PKC? immunoreactivity was surveyed throughout the brain and showed no change following acute ethanol injection
Measurement of the branching fraction
The 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
Outcome evaluation of the Kirklees Paired Reading Project.
The impact of services to help schools to guide and support parents (and
peer tutors) in the use of the Paired Reading technique for improving
children's reading was evaluated. Compared to all studies
previously reported in the literature taken together, the Kirklees
research yielded more than double the volume of pre-post norm referenced
outcome data, double the amount of control or comparison group data and
triple the amount of follow-up data. Additionally, in Kirklees
baseline data were compared with pre-post data to give a time series
comparison. Although outcomes on reading tests were slightly less
favourable than those selectively reported in the previous literature,
the research suggested that an adequate level of effectiveness was
possible in a large field study incorporating many schools in one Local
Education Authority, representing a significant test of the
generalisability and replicability of the technique. The Kirklees study
also examined the influence of a number of organisational, demographic
and within-subject factors as they related to outcomes. In addition a
very large volume of subjective feedback from teacher, parent and child
participants was collected in a systematic way, and proved extremely
positive. The research also examined the inter-relationship of the
various outcome measures deployed with a view to assessing their
relative reliability and validity for this purpose. As very few
process data were gathered it was not possible to demonstrate what
proportion of participants actually utilised the Paired Reading
technique in the way they were trained. It is thus difficult to partial
out to what extent the positive outcomes are due to the impact of the
technique and/or the service delivery support package. However, the
technique and service delivery package combined are suggested by the data
to be associated with improvements in children's reading skill and
attitude to reading. The study provides a number of pointers to the probable success of the Paired Reading approach but conclusive evidence on
this must await the findings of properly controlled studies
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