1,815 research outputs found
Further results on elementary Lie algebras and Lie A-algebras.
A finite-dimensional Lie algebra L over a field F of characteristic zero is called elementary if each of its subalgebras has trivial Frattini ideal; it is an A-algebra if every nilpotent subalgebra is abelian. This paper is a continuation of the study of these algebras initiated by the authors in a previous paper. If we denote by , , , , the classes of A-algebras, almost algebraic algebras, E-algebras, elementary algebras and -free algebras respectively, then it is shown that: \mathcal{L} \subset \Phi \subset \mathcal{G} \mathcal{L} \subset \mathcal{A} \subset \mathcal{E} \mathcal{G} \cap \mathcal{A} = \mathcal{L}. It is also shown that if L is a semisimple Lie algebra all of whose minimal parabolic subalgebras are -free then L is an A-algebra, and hence elementary. This requires a number of quite delicate properties of parabolic subalgebras. Finally characterisations are given of -algebras and of Lie algebras all of whose proper subalgebras are elementary
Research and development of high temperature resistant polymeric film forming material final summary report, 1 mar. 1961 - 17 apr. 1962
Preparation of poly-organometallosiloxane polymers from reactions between bis-dialkylamino metal derivatives and silanediol
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Is tertiary education in dire straits? (Is it money for nothing of just another brick in the wall?)
An Evaluation of the Impact of the Social Care Modernisation Programme on the Implementation of Direct Payments London
Drug-induced stress granule formation protects sensory hair cells in mouse cochlear explants during ototoxicity
Stress granules regulate RNA translation during cellular stress, a mechanism that is generally presumed to be protective, since stress granule dysregulation caused by mutation or ageing is associated with neurodegenerative disease. Here, we investigate whether pharmacological manipulation of the stress granule pathway in the auditory organ, the cochlea, affects the survival of sensory hair cells during aminoglycoside ototoxicity, a common cause of acquired hearing loss. We show that hydroxamate (-)-9, a silvestrol analogue that inhibits eIF4A, induces stress granule formation in both an auditory cell line and ex-vivo cochlear cultures and that it prevents ototoxin-induced hair-cell death. In contrast, preventing stress granule formation using the small molecule inhibitor ISRIB increases hair-cell death. Furthermore, we provide the first evidence of stress granule formation in mammalian hair cells in-vivo triggered by aminoglycoside treatment. Our results demonstrate that pharmacological induction of stress granules enhances cell survival in native-tissue, in a clinically-relevant context. This establishes stress granules as a viable therapeutic target not only for hearing loss but also other neurodegenerative diseases.EI:595 - Action on Hearing Loss; 091092/Z/09/Z - Wellcome Trust (Wellcome); MR/N004329/1 - RCUK | Medical Research Council (MRC)Published versio
A Water Maser and Ammonia Survey of GLIMPSE Extended Green Objects (EGOs)
We present the results of a Nobeyama 45-m water maser and ammonia survey of
all 94 northern GLIMPSE Extended Green Objects (EGOs), a sample of massive
young stellar objects (MYSOs) identified based on their extended 4.5 micron
emission. We observed the ammonia (1,1), (2,2), and (3,3) inversion lines, and
detect emission towards 97%, 63%, and 46% of our sample, respectively (median
rms ~50 mK). The water maser detection rate is 68% (median rms ~0.11 Jy). The
derived water maser and clump-scale gas properties are consistent with the
identification of EGOs as young MYSOs. To explore the degree of variation among
EGOs, we analyze subsamples defined based on MIR properties or maser
associations. Water masers and warm dense gas, as indicated by emission in the
higher-excitation ammonia transitions, are most frequently detected towards
EGOs also associated with both Class I and II methanol masers. 95% (81%) of
such EGOs are detected in water (ammonia(3,3)), compared to only 33% (7%) of
EGOs without either methanol maser type. As populations, EGOs associated with
Class I and/or II methanol masers have significantly higher ammonia linewidths,
column densities, and kinetic temperatures than EGOs undetected in methanol
maser surveys. However, we find no evidence for statistically significant
differences in water maser properties (such as maser luminosity) among any EGO
subsamples. Combining our data with the 1.1 mm continuum Bolocam Galactic Plane
Survey, we find no correlation between isotropic water maser luminosity and
clump number density. Water maser luminosity is weakly correlated with clump
(gas) temperature and clump mass.Comment: Astrophysical Journal, accepted. Emulateapj, 24 pages including 24
figures, plus 9 tables (including full content of online-only tables
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An isotopic investigation into calving seasonality, diet and dairying in British Prehistoric cattle. Reconstructing animal husbandry at a sub-annual resolution using multi-isotope analysis and intra-tooth sampling.
The detection of dairying is essential to understand prehistoric economies, particularly in northwest Europe, where a high degree of lactose tolerance implies that fresh milk has long been a significant dietary component. Domestic cattle (Bos taurus) are biologically able to breed year-round, potentially enabling farmers to select a calving strategy to suit their economic focus. Published literature and interviews with farmers suggests that spring calving would have been favoured by economies focussed on meat or storable dairy products, whereas the year-round provision of fresh milk would have required two calving seasons, in spring and autumn, or an extended period through spring, summer and autumn.
This thesis uses intra-tooth isotope ratio analysis of cattle tooth enamel to predict birth seasonality as an indicator of dairying. Analysis was performed on first, second and third cattle molars from the archaeological sites of Mine Howe, Pool and Earl’s Bu (Iron Age and Viking period Orkney), Old Scatness (Iron Age Shetland) and Grimes Graves (Bronze Age Norfolk). Modern molars from Chillingham Wild White cattle were also analysed.
A new method to determine cattle birth seasonality has been proposed utilising the isotopic patterning (δ13C, δ18O) recorded within first and second molar enamel. Results suggest that birth seasonality estimates are of sufficient accuracy to discriminate between single-and multiple-season calving. Although Pool and Grimes Graves have been interpreted as dairying sites from their age-at-death slaughter patterns, birth seasonality predictions imply an economy focussed on year-round fresh milk at Pool but an emphasis on storable dairy products at Grimes Graves.
In addition, it has been demonstrated that intra-tooth enamel data can provide information regarding sub-annual variation in diet and environment. A new method to investigate weaning strategy has also been proposed
State St Letter to OTS
This letter is addressed to the Office of the Comptroller of the Currency, the Board of Governors of the Federal Reserve System, Federal Deposit Insurance Corporation, and the Office of Thrift Supervisio
Effectiveness of new agri-environment schemes in conserving arable plants in intensively farmed landscapes
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