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1.
Phys Rev Lett ; 117(26): 267701, 2016 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-28059534

RESUMO

We analyze the quantum quench dynamics in the formation of a phase-biased superconducting nanojunction. We find that in the absence of an external relaxation mechanism and for very general conditions the system gets trapped in a metastable state, corresponding to a nonequilibrium population of the Andreev bound states. The use of the time-dependent full counting statistics analysis allows us to extract information on the asymptotic population of even and odd many-body states, demonstrating that a universal behavior, dependent only on the Andreev state energy, is reached in the quantum point contact limit. These results shed light on recent experimental observations on quasiparticle trapping in superconducting atomic contacts.

2.
J Hazard Mater ; 148(1-2): 419-27, 2007 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-17408853

RESUMO

A new system for destroying volatile organic waste based on a microwave plasma torch that operates at atmospheric pressure and is coupled to a reactor affording isolation of output gases and adjustment of the plasma discharge atmosphere is proposed. The system was assessed by using carbon tetrachloride as the target volatile organic compound (VOC) and argon as the main gas in a helium atmosphere. Under optimal conditions, a microwave power of less than 1000 W was found to reduce the CCl(4) concentration at the reactor outlet to the parts-per-billion level and hence to virtually completely destroy the VOC. With high argon flow-rates and CCl(4) concentrations, the energy efficiency can reach levels in excess of 3000 g/kWh. Output gases and species in the plasma, which were identified by gas chromatography and light emission spectroscopy, respectively, were found to include no halogen-containing derivatives resulting from the potential cleavage of CCl(4). In fact, the main gaseous byproducts obtained were CO(2), NO and N(2)O, in addition to small traces of Cl(2), and the solid byproducts Cl(2)Cu and various derivatives depending on the particular reactor zone.


Assuntos
Tetracloreto de Carbono/efeitos da radiação , Micro-Ondas , Pressão Atmosférica , Dióxido de Carbono/análise , Cloro/análise , Cromatografia Gasosa , Recuperação e Remediação Ambiental/métodos , Gases , Óxido Nítrico/análise , Compostos Orgânicos/efeitos da radiação , Volatilização
3.
Prev Vet Med ; 75(3-4): 239-50, 2006 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-16730818

RESUMO

Three thousand one hundred and ninety-three Merino-breeding males were genotyped for Scrapie-resistance gene. They showed a high frequency of ARQ allele while VRQ allele frequency, linked to the highest susceptibility, was close to 0. Alleles linked to Scrapie-susceptibility frequencies have been studied in different Merino flocks. Most of the variability is intraflock, not interflock. In addition, there is an excess of heterozygotes due to crossbreeding or Wahlund effect. Five control and prevention strategies were studied: first genotyping males and females and eliminating VRQ carriers and ARQ/ARQ rams; second genotyping males and females and eliminating VRQ carriers; third genotyping males and eliminating VRQ carriers and ARQ/ARQ rams; fourth genotyping males and using only as breeders ARR/ARR, ARR/AHQ, AHQ/AHQ and ARQ/ARQ rams; fifth genotyping males and using only as breeders ARR/ARR, ARR/AHQ and AHQ/AHQ rams. They were simulated from allelic and genotypic frequencies to decide which animals had to be genotyped and which animals had to be eliminated due to their genotypes and risk levels. The third option, to genotype rams and to eliminate ARQ/ARQ and VRQ carriers, would be the best strategy to improve the resistance and would cause minimal cost and loss of animals.


Assuntos
Frequência do Gene , Imunidade Inata/genética , Scrapie/genética , Scrapie/prevenção & controle , Animais , Cruzamento/métodos , Feminino , Predisposição Genética para Doença , Genótipo , Masculino , Ovinos
4.
Rev Esp Anestesiol Reanim ; 52(6): 363-6, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-16038177

RESUMO

A 9-year-old boy diagnosed with gingival hypertrophy and with a history of West syndrome and associated low platelet levels underwent gingival reduction surgery. Because difficult intubation was foreseen, the fiberoptic tube was inserted through the nose with the patient breathing spontaneously under remifentanil for sedation and analgesia. The procedure was carried out under balanced general anesthesia and with standard monitoring. At the end of gingivectomy, a tracheostomy was performed and the patient was transferred to the pediatric intensive care unit for postoperative observation.


Assuntos
Obstrução das Vias Respiratórias/etiologia , Analgésicos Opioides/uso terapêutico , Broncoscopia , Hipertrofia Gengival/complicações , Hipnóticos e Sedativos/uso terapêutico , Intubação Intratraqueal , Nariz , Piperidinas/uso terapêutico , Espasmos Infantis/complicações , Anticonvulsivantes/efeitos adversos , Criança , Tecnologia de Fibra Óptica , Hipertrofia Gengival/induzido quimicamente , Hipertrofia Gengival/cirurgia , Humanos , Lactente , Deficiência Intelectual/complicações , Intubação Intratraqueal/instrumentação , Masculino , Fenitoína/efeitos adversos , Remifentanil , Espasmos Infantis/tratamento farmacológico , Extração Dentária , Traqueostomia
5.
Mil Med ; 166(11): 959-65, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11725324

RESUMO

UNLABELLED: The objective of this study was to examine the attitudes, characteristics, and opinions about smoking of a group of young asthmatic men. POPULATION AND METHODS: An anonymous, personal questionnaire was administered to 611 young male volunteers who had been diagnosed with asthma (according to the National Heart, Lung, and Blood Institute/World Health Organization Global Initiative for Asthma, 1995) in the respiratory disease and allergy clinics of the Burgos Military Hospital (Spain). This questionnaire contained items related to personal information, asthma characteristics, opinions about smoking, and information related to smoking habits. RESULTS: Six hundred patients with asthma completed the questionnaire. All were men, mean age 20.16 +/- 3.03 years; 189 (31.5%) were smokers and 16 (2.5%) were ex-smokers. Mean age at onset of regular smoking was 16.46 +/- 2 years. Sixty-five percent (65.07%) smoked fewer than 10 cigarettes per day. Most of the smoking asthmatics had mild asthma (58.9%). Eighty-eight percent (88.3%) had moderate dependence. Many of the smoking asthmatics were contemplating stopping smoking (54%), and 59% had tried before to stop. Concern about health was the main reason given for stopping smoking. Asthmatics who smoked had a higher percentage of smokers among family members, friends, and colleagues than nonsmoking asthmatics. Attitudes toward smoking were more permissive among smoking asthmatics. Only 36.64% of the total had received information about tobacco previously. In the sample group, 7% claimed that they did not smoke but their carbon monoxide concentration in exhaled air was 10 ppm or higher. CONCLUSIONS: There were no differences in the onset of the smoking habit between asthmatic and nonasthmatic young people. A large percentage of the smoking asthmatics were considering smoking cessation, motivated mainly by their asthma condition. The group as a whole had little previous information about tobacco.


Assuntos
Asma/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Fumar/psicologia , Adulto , Idade de Início , Distribuição de Qui-Quadrado , Humanos , Masculino , Inquéritos e Questionários
6.
J Phys Condens Matter ; 24(38): 385303, 2012 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-22945559

RESUMO

We analyze the spectral density of a single level quantum dot coupled to superconducting leads focusing on the Andreev states appearing within the superconducting gap. We use two complementary approaches: the numerical renormalization group and the Hartree-Fock approximation. Our results show the existence of up to four bound states within the gap when the ground state is a spin doublet (π phase). Furthermore the results demonstrate the reliability of the mean field description within this phase. This is understood from a complete correspondence that can be established between the exact and the mean field quasiparticle excitation spectrum within the gap.

7.
J Hazard Mater ; 186(1): 820-6, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21146292

RESUMO

In this study, the destruction rate of a volatile waste destruction system based on a microwave plasma torch operating at atmospheric pressure was investigated. Atmospheric air was used to maintain the plasma and was introduced by a compressor, which resulted in lower operating costs compared to other gases such as argon and helium. To isolate the output gases and control the plasma discharge atmosphere, the plasma was coupled to a reactor. The effect of the gas flow rate, microwave power and initial concentration of compound on the destruction efficiency of the system was evaluated. In this study, trichloroethylene and carbon tetrachloride were used as representative volatile organic compounds to determine the destruction rate of the system. Based on the experimental results, at an applied microwave power less than 1000 W, the proposed system can reduce input concentrations in the ppmv range to output concentrations at the ppbv level. High air flow rates and initial concentrations produced energy efficiency values greater than 1000 g/kW h. The output gases and species present in the plasma were analysed by gas chromatography and optical emission spectroscopy, respectively, and negligible amounts of halogenated compounds resulting from the cleavage of C(2)HCl(3) and CCl(4) were observed. The gaseous byproducts of decomposition consisted mainly of CO(2), NO and N(2)O, as well as trace amounts of Cl(2) and solid CuCl.


Assuntos
Pressão Atmosférica , Micro-Ondas , Tricloroetileno/química
8.
9.
Phys Rev Lett ; 72(4): 554-557, 1994 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-10056462
11.
Phys Rev B Condens Matter ; 36(11): 6149-6151, 1987 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-9942302
12.
Phys Rev B Condens Matter ; 38(14): 10047-10050, 1988 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-9945835
14.
16.
Phys Rev B Condens Matter ; 41(12): 8553-8556, 1990 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9993189
20.
Phys Rev B Condens Matter ; 53(14): R8891-R8894, 1996 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9982478
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