22,686 research outputs found
Trends in social capital: Membership of associations in Great Britain, 1991–98
This Note uses the British Household Panel Study (BHPS) to consider the changing volume and distribution of voluntary association membership (and hence social capital) in Great Britain. We aim to supplement Hall's study of trends in social capital published in this Journal with more recent and longitudinal data. This allows us to show that whilst the volume of social capital is not declining, it is becoming increasingly class specific, and that its relative aggregate stability masks considerable turnover at the individual level. These findings are significant for current debates on social capital
Investigation of the chemical kinetics of an advanced high energy propellant system Quarterly progress report, 1 Jun. - 1 Sep. 1968
Reaction kinetics of high energy oxygen difluoride diborane propellant syste
Chromospheric Inversions of a Micro-flaring Region
We use spectropolarimetric observations of the Ca II 8542~\AA\ line, taken
from the Swedish 1-m Solar Telescope (SST), in an attempt to recover dynamic
activity in a micro-flaring region near a sunspot via inversions. These
inversions show localized mean temperature enhancements of 1000~K in the
chromosphere and upper photosphere, along with co-spatial bi-directional
Doppler shifting of 5 - 10 km s. This heating also extends along a
nearby chromospheric fibril, co-spatial to 10 - 15 km s down-flows.
Strong magnetic flux cancellation is also apparent in one of the footpoints,
concentrated in the chromosphere. This event more closely resembles that of an
Ellerman Bomb (EB), though placed slightly higher in the atmosphere than is
typically observed.Comment: 9 pages, 9 figures, accepted in ApJ. Movies are stored here:
https://star.pst.qub.ac.uk/webdav/public/areid/Microflare
Recommended from our members
R-PEKS: RBAC Enabled PEKS for Secure Access of Cloud Data
In the recent past, few works have been done by combining attribute-based access control with multi-user PEKS, i.e., public key encryption with keyword search. Such attribute enabled searchable encryption is most suitable for applications where the changing of privileges is done once in a while. However, to date, no efficient and secure scheme is available in the literature that is suitable for these applications where changing privileges are done frequently. In this paper our contributions are twofold. Firstly, we propose a new PEKS scheme for string search, which, unlike the previous constructions, is free from bi-linear mapping and is efficient by 97% compared to PEKS for string search proposed by Ray et.al in TrustCom 2017. Secondly, we introduce role based access control (RBAC) to multi-user PEKS, where an arbitrary group of users can search and access the encrypted files depending upon roles. We termed this integrated scheme as R-PEKS. The efficiency of R-PEKS over the PEKS scheme is up to 90%. We provide formal security proofs for the different components of R-PEKS and validate these schemes using a commercial dataset
Squeezing and entanglement of matter-wave gap solitons
We study quantum squeezing and entanglement of gap solitons in a
Bose-Einstein condensate loaded into a one-dimensional optical lattice. By
employing a linearized quantum theory we find that quantum noise squeezing of
gap solitons, produced during their evolution, is enhanced compared with the
atomic solitons in a lattice-free case due to intra-soliton structure of
quantum correlations induced by the Bragg scattering in the periodic potential.
We also show that nonlinear interaction of gap solitons in dynamically stable
bound states can produce strong soliton entanglement.Comment: 4 pages, 5 figure
X-ray pulsations from the radio-quiet gamma-ray pulsar in CTA 1
Prompted by the Fermi LAT discovery of a radio-quiet gamma-ray pulsar inside
the CTA 1 supernova remnant, we obtained a 130 ks XMM-Newton observation to
assess the timing behavior of this pulsar. Exploiting both the unprecedented
photon harvest and the contemporary Fermi LAT timing measurements, a 4.7 sigma
single peak pulsation is detected, making PSR J0007+7303 the second example,
after Geminga, of a radio-quiet gamma-ray pulsar also seen to pulsate in
X-rays. Phase-resolved spectroscopy shows that the off-pulse portion of the
light curve is dominated by a power-law, non-thermal spectrum, while the X-ray
peak emission appears to be mainly of thermal origin, probably from a polar cap
heated by magnetospheric return currents, pointing to a hot spot varying
throughout the pulsar rotation.Comment: 19 pages, 4 figures. Accepted for publication in ApJ Letter
Chemical extraction and optimization of intracellular β-galactosidase production from the bacterium Arthrobacter oxydans using Box-Behnken design of response surface methodology
Present study demonstrated the isolation of most promising β-galactosidase producing bacterial strain SB from soil. Morphological, biochemical, and 16s rRNA sequence analysis identified the bacterial strain as Arthrobacter oxydans. Several chemicals, including SDS, Triton X-100, Tween 20, isoamyl alcohol, and toluene-acetone mixture, were applied for extraction of intracellular β-galactosidase from the bacterial strain Arthrobacter oxydans. Among these, Tween 20 was recorded to be most effective. Role of pH, temperature, and shaker speed on production of β-galactosidase was evaluated using Box-Behnken design of response surface methodology. According to Box-Behnken analysis, optimum production of β-galactosidase (21.38 U (mg–1 protein)) is predicted at pH 6.76, temperature 36.1 °C, and shaker speed 121.37 r.p.m. The parameters are validated with the nearest value
Underwater sounds from ribbon seal, Phoca (Histriophoca) fasciata
This paper is not subject to U.S. copyright. The definitive version was published in Fishery Bulletin 75 (1977): 450-453.Intense downward frequency "sweeps" and broadband
"puffing" sounds were recorded underwater
in the presence of ribbon seal, Phoca (Histriophoca)
fasciata Zimmerman 1783. The recordings
were made in the waters off Savoonga, St.
Lawrence Island, Alaska, on 16, 17, 18, and 23
May 1967.Arctic Institute
of North America under contractural agreements
with the Office of Naval Research
The natural resources of Bolinas Lagoon: their status and future
This publication is an integral part of the Department's high-priority inventory and assessment of coastal marshland and tideflat resources. It is intended as a guide for citizens, planners, administrators, and all others interested in the use and development of coastal lands and waters.
Although the resources and problems of Bolinas Lagoon have probably been the subject of more biological and physical investigations than any small estuarine area of the California coast, many of the pertinent reports and information are not readily available to the public.
Consequently, it is one purpose of this report to summarize the lagoon's history, ecological attractions, educational values and the problems facing its continued existence. At the same time, it should provide concerned citizens with a knowledge of the sources of additional and more specific information.
Publication of this report is consistent with the obligation of the Department of Fish and Game to do everything in its power to protect and maintain the State's fish and wildlife resources. Therefore, its purpose transcends local issues on pollution and development, and the Department is, in fact, submitting a report to the people on the status and future of part of its inheritance and the dowry of coming generations.
The report is the third of a scheduled series. It follows similar releases on Upper Newport Bay (Orange County) and Goleta Slough (Santa Barbara county) in March and June of 1970. Documentation of the resources of other critical areas is in progress. There will be future reports of this nature on Elkhorn Slough, Morro Bay, Tomales Bay, Humboldt Bay, and highly threatened marshlands in southern California. (137 pp.
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