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1.
Emerg Med J ; 24(12): 851-3, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18029523

RESUMO

Commercial filming of patients in the hospital and now the prehospital environment is becoming increasingly common. Television programmes that focus on medical emergencies with real footage of events remain highly successful and can make compelling viewing for both medical professionals and the general public alike. Recently several commentators have questioned the ethical aspects of filming in hospital emergency departments, and noted the lack of available evidence. This article reviews commercial filming and its impact in the prehospital environment and examines the ethical implications and current guidance in this unique setting.


Assuntos
Serviços Médicos de Emergência/ética , Televisão/ética , Humanos , Consentimento Livre e Esclarecido/ética , Competência Mental , Medicina Estatal/ética , Reino Unido
2.
Nature ; 383(6599): 418-20, 1996 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-8837771

RESUMO

Volatile compounds in comets are the most pristine materials surviving from the time of formation of the Solar System, and thus potentially provide information about conditions that prevailed in the primitive solar nebula. Moreover, comets may have supplied a substantial fraction of the volatiles on the terrestrial planets, perhaps including organic compounds that played a role in the origin of life on Earth. Here we report the detection of hydrogen isocyanide (HNC) in comet Hyakutake. The abundance of HNC relative to hydrogen cyanide (HCN) is very similar to that observed in quiescent interstellar molecular clouds, and quite different from the equilibrium ratio expected in the outermost solar nebula, where comets are thought to form. Such a departure from equilibrium has long been considered a hallmark of gas-phase chemical processing in the interstellar medium, suggesting that interstellar gases have been incorporated into the comet's nucleus, perhaps as ices frozen onto interstellar grains. If this interpretation is correct, our results should provide constraints on the temperature of the solar nebula, and the subsequent chemical processes that occurred in the region where comets formed.


Assuntos
Meio Ambiente Extraterreno , Cianeto de Hidrogênio/análise , Meteoroides , Congelamento , Gelo , Análise Espectral
3.
Astrophys J ; 380: L39-42, 1991 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-11538087

RESUMO

We have detected a new carbon-chain molecule, CCO(3 sigma-), in the cold, dark molecular cloud TMC-1. The excitation temperature and the column density of CCO are, respectively, approximately 6 K and approximately 6 x 10(11) cm-2. This column density corresponds to a fractional abundance relative to H2 of approximately 6 x 10(-11). This value is two orders of magnitude less than the abundance of the related carbon-chain molecule CCS, and about half that of C3O. The formation mechanism for CCO is discussed.


Assuntos
Carbono/análise , Carbono/química , Sistema Solar , Fenômenos Astronômicos , Astronomia , Carbono/classificação , Modelos Moleculares , Ondas de Rádio , Temperatura
4.
Astrophys J ; 335(2): L89-93, 1988 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11538462

RESUMO

We report the detection of the acetylene derivative propynal (HC triple bond CCHO) in the cold cloud TMC-1, with an abundance that is very close to that for the related species tricarbon monoxide (C3O). Propadienone, an isomer of propynal with the formula H2C=C=C=O, was not detected and is hence less abundant than either C3O or HC2CHO.


Assuntos
Aldeídos/química , Carbono/química , Meio Ambiente Extraterreno , Fenômenos Astronômicos , Astronomia , Carbono/análise , Monóxido de Carbono , Fenômenos Químicos , Química , Isomerismo , Modelos Químicos
5.
Astrophys J ; 300(2): L79-84, 1986 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11542051

RESUMO

We report the astronomical detections of several ammonia inversion transitions involving nonmetastable levels with energies as high s 1090 K above the ground state. The (J, K) = (9, 6) inversion transition shows maser-like emission in the directions of W51, NGC 7538, W49, and DR 21(OH). The NH3 (6, 3) line exhibits similar characteristics in W51 but is seen in absorption in NGC 7538. These are the first definite detections of ammonia masers in space. The intensities and narrow line widths (0.5-1.5 km s-1) for the emission features are in contrast to the previously detected broad, weak, nonmetastable lines attributed to thermal emission in these sources. Temporal variability appears to be evident in the (9, 6) emission in W49 over a 4 month period. The highly excited (J, K) = (9, 6) and (6, 3) ammonia lines are found in regions containing compact H II regions and strong infrared sources with associated H2O and OH masers; i.e., in regions of active star formation.


Assuntos
Amônia/análise , Astronomia/métodos , Meio Ambiente Extraterreno , Astronomia/instrumentação , Micro-Ondas , Temperatura
6.
Astrophys J ; 297(1): 302-8, 1985 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11540840

RESUMO

We report the measurement of three new lines of C3O in TMC-1. The observed peak antenna temperatures, appropriately corrected for atmospheric and telescope losses, are found to be consistent with a large velocity gradient radiative transfer model whose parameters span the range of standard values for this cloud. The derived fractional abundance for C3O is 1.4 x 10(-10), comparable with the results predicted from a model calculation based on a gas-phase ion-molecule reaction scheme. The results of negative searches for C3O in six other sources are not inconsistent with expected conditions in these clouds.


Assuntos
Astronomia , Monóxido de Carbono/análise , Meio Ambiente Extraterreno , Modelos Químicos , Fenômenos Astronômicos , Monóxido de Carbono/química , Temperatura
7.
Nature ; 310(5973): 125-6, 1984 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-11541993

RESUMO

The cold dark interstellar Taurus Molecular Cloud One (TMC-1) is a rich source of acetylenic and polyacetylenic molecular species. As well as linear closed-shell molecules (H(C triple bond C)nCN) and symmetric rotors (CH3C triple bond CH, CH3C triple bond CCN), several radicals (C triple bond CH, C triple bond CCN, (C triple bond C2H) have also been identified, many of which had not been studied previously in the laboratory. Whether the observed abundances can be understood in terms of purely gas-phase ion-molecule chemical schemes, which produce reasonable agreement for the simplest polyatomic species, is unclear; alternative models involving the particulate interstellar grains as catalysts or sources have also been suggested. We now report the detection in TMC-1 of a new molecule, tricarbon monoxide (C3O), whose pure rotational spectrum has only very recently been studied in the laboratory. As C3O is the first known interstellar carbon chain molecule to contain oxygen, its existence places an important new constraint on chemical schemes for cold interstellar clouds. In fact, the observed abundance of tricarbon monoxide fits quite well into our model of galactochemistry.


Assuntos
Monóxido de Carbono/análise , Monóxido de Carbono/química , Carbono/química , Poeira Cósmica/análise , Meio Ambiente Extraterreno , Fenômenos Astronômicos , Astronomia , Carbono/análise
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