334,522 research outputs found
Many-electron theory of resonant charge transfer: Role of surface states in He and He+ scattering off Si(100)
A many-electron theory of resonant charge transfer, originally formulated for the scattering of an atom with an empty valence orbital from a surface, is extended to treat the case where the valence orbital is initially occupied by one or two electrons. The scattering of He and He+ from the Si(001) surface is investigated. The interaction is assumed to be with the narrow band of surface states, and not the much wider bulk band. As a result, considerable oscillations are found in the ionization and/or neutralization probabilities as a function of the incident energy.PT: J; CR: AMOS AT, 1989, ADV CHEM PHYS, V76, P335 AMOS AT, 1989, SOLID STATE COMMUN, V71, P449 BLOSS W, 1978, SURF SCI, V72, P277 BRAKO R, 1981, SURF SCI, V108, P253 BURROWS BL, 1984, Q APPL MATH, V42, P73 BURROWS BL, 1990, J PHYS A-MATH GEN, V23, P1101 BURROWS BL, 1991, SURF SCI, V253, P365 CHADI DJ, 1975, PHYS STATUS SOLIDI B, V68, P405 HAGSTRUM HD, 1954, PHYS REV, V96, P336 HAGSTRUM HD, 1961, PHYS REV, V122, P83 HERMAN F, 1963, ATOMIC STRUCTURE CAL IHM J, 1980, PHYS REV B, V21, P4592 MUDA Y, 1980, SURF SCI, V97, P283 MUDA Y, 1988, NUCL INSTRUM METH B, V33, P388 MUDA Y, 1988, PHYS REV B, V37, P7048 PAULING L, 1935, INTRO QUANTUM MECHAN ROBERTS N, 1990, SURF SCI, V236, P112 SOUDA R, 1985, SURF SCI, V150, L59 SOUDA R, 1986, NUCL INSTRUM METH B, V15, P114 SOUDA R, 1986, NUCL INSTRUM METH B, V15, P138 SOUDA R, 1986, SURF SCI, V176, P657 SULSTON KW, 1988, PHYS REV B, V37, P9121 SULSTON KW, 1988, SURF SCI, V197, P555 SULSTON KW, 1989, SURF SCI, V244, P543 WEAKLIEM PC, 1990, SURF SCI, V232, L219 WEISENDANGER R, 1990, SURF SCI, V232, P1; NR: 26; TC: 4; J9: PHYS REV B; PG: 11; GA: HZ245Source type: Electronic(1
Rotational Energy Transfer in I2(B ) Colliding with I2 Ar and He Experiment and Fitting Law
Book review: The theatrical public sphere, by Christopher B. Balme
Book review of: The theatrical public sphere, by Christopher B. Balme. Cambridge: Cambridge University Press, 2014; ISBN 9781107006836 (£60.00)Publisher PD
Branching fraction and CP asymmetry of the decays B+→K0Sπ+ and B+→K0SK+
An 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
Protecting Animals 36: Author Witi Ihimaera
In this very special episode of Knowing Animals I am joined by beloved New Zealand author Witi Ihimaera. Witi has written many books featuring nonhuman animals. He offers us a non-colonial lens through which to think about the human/nonhuman relationship
Replication Data for: Mesospheric Q2DW interactions with four migrating tides at 53N latitude: zonal wavenumber identification through dual-station approaches
- the dataset comprises three Matlab .mat files, namely, Fig2.mat, Fig3.mat, and Fig4.mat, containing the data used for Figures 2, 3, and 4 in the manuscript, respectively.
- In each file, each variable contains data for one panel, named after the panel labels, namely,‘a’, ‘b’, … . All variables are stored in the type of ‘structure array’. The Field names of each structure array specify the quantity and its unit.
Please contact He, Maosheng([email protected]) for assistance and further information
B vitamins and cognitive performance in older adults: Review
A copious amount of scientific scrutiny has been dedicated to documenting typical and atypical human ageing, with a substantial body of work focusing upon the impact of lifestyle choices. One such lifestyle choice is that of diet and, in particular, micronutrient ingestion. Epidemiological studies have reported positive associations between B vitamin status and cognitive function, including negative associations between biological markers (i.e., homocysteine) of dysregulated one-carbon metabolism and cognitive function. This has led to a surge of randomised control trials (RCTs) investigations into B vitamin therapy. However, results have continuingly failed to show beneficial behavioural effects. Despite this, results reliably show treatment-related increases in B vitamin level and decreases in homocysteine level—both of which have been identified as risk factors for atypical ageing. In this paper we argue that it would be premature to conclude that B vitamin therapy has no potential and that more research is needed to systematically investigate the optimal dose, the therapeutic “window,” and individual differences in therapy responders and nonresponders. We start with a brief look at one-carbon metabolism and then consider the evidence from epidemiological studies and RCTs in relation to three specific B vitamins: folic acid (B9), pyridoxine (B6), and cobamides (B12)
Author Under Sail The Imagination of Jack London, 1893-1902
In Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
Data Ellipses, HE Plots and Reduced-Rank Displays for Multivariate Linear Models: SAS Software and Examples
This paper describes graphical methods for multiple-response data within the framework of the multivariate linear model (MLM), aimed at understanding what is being tested in a multivariate test, and how factor/predictor effects are expressed across multiple response measures. In particular, we describe and illustrate a collection of SAS macro programs for: (a) Data ellipses and low-rank biplots for multivariate data, (b) HE plots, showing the hypothesis and error covariance matrices for a given pair of responses, and a given effect, (c) HE plot matrices, showing all pairwise HE plots, and (d) low-rank analogs of HE plots, showing all observations, group means, and their relations to the response variables.
He+ dominance in the plasmasphere during geomagnetically disturbed periods: 1. Observational results
Observations made by the DMSP 1710 satellite during the recovery phase from geomagnetic disturbances in June 1991 show regions of He+ dominance around 830 km altitude at 09:00 MLT. These regions are co-located with a trough in ionisation observed around 55degrees in the winter hemisphere. Plasma temperature and concentration observations made during the severe geomagnetic storm of 24 March 1991 are used as a case study to determine the effects of geomagnetic disturbances along the orbit of the F10 satellite. Previous explanations for He+ dominance in this trough region relate to the part of the respective flux tubes that is in darkness. Such conditions are not relevant for this study, since the whole of the respective flux tubes are sunlit. A new mechanism is proposed to explain the He+ dominance in the trough region. This mechanism is based on plasma transport and chemical reaction effects in the F-region and topside ionosphere, and on the time scales for such chemical reactions. Flux tubes previously depleted by geomagnetic storm effects refill during the recovery phase from the ionosphere as a result of pressure differences along the flux tubes. Following a geomagnetic disturbance, the He+ ion recovers quickly via the rapid photoionisation of neutral helium, in the F-region and the topside. The recovery of the O+ and H+ ions is less rapid. This is proposed as a result of the respective charge exchange reactions with neutral atomic hydrogen and oxygen. Preliminary model calculations support the proposed mechanism
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