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1.
Phys Rev Lett ; 125(18): 180603, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33196219

RESUMO

Constraints on work extraction are fundamental to our operational understanding of the thermodynamics of both classical and quantum systems. In the quantum setting, finite-time control operations typically generate coherence in the instantaneous energy eigenbasis of the dynamical system. Thermodynamic cycles can, in principle, be designed to extract work from this nonequilibrium resource. Here, we isolate and study the quantum coherent component to the work yield in such protocols. Specifically, we identify a coherent contribution to the ergotropy (the maximum amount of unitarily extractable work via cyclical variation of Hamiltonian parameters). We show this by dividing the optimal transformation into an incoherent operation and a coherence extraction cycle. We obtain bounds for both the coherent and incoherent parts of the extractable work and discuss their saturation in specific settings. Our results are illustrated with several examples, including finite-dimensional systems and bosonic Gaussian states that describe recent experiments on quantum heat engines with a quantized load.

2.
Cancer Epidemiol ; 37(6): 857-63, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24063904

RESUMO

BACKGROUND: Net survival is the survival that would be observed if cancer were the only possible cause of death. Although it is an important epidemiological tool allowing temporal or geographical comparisons, it cannot inform on the "crude" probability of death of cancer patients; i.e., when taking into account other possible causes of deaths. METHODS: In this work, we provide estimates of the crude probabilities of death from cancer and from other causes as well as the probability of being alive up to ten years after cancer diagnosis according to the age and year of diagnosis. Based on a flexible excess hazard model providing unbiased estimates of net survival, our methodology avoids the pitfalls associated with the use of the cause of death. We used data from FRANCIM, the French network of cancer registries, and studied five common cancer sites: head and neck, breast, prostate, lung, and colorectal cancers. RESULTS: For breast, prostate, and colorectal cancers, the impact of the other causes on the total probability of death increased with the age at diagnosis whereas it remained negligible for lung and head and neck cancers whatever the age. For breast, prostate, and colorectal cancer, the more recently was the cancer diagnosed, the less was the probability of death from cancer. CONCLUSION: The crude probability of death is an intuitive concept that may prove particularly useful in choosing an appropriate treatment, or refining the indication of a screening strategy by allowing the clinician to estimate the proportion of cancer patients who will die specifically from cancer.


Assuntos
Neoplasias da Mama/mortalidade , Neoplasias Colorretais/mortalidade , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias Pulmonares/mortalidade , Modelos Estatísticos , Neoplasias da Próstata/mortalidade , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Feminino , Seguimentos , França/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Sistema de Registros , Medição de Risco , Taxa de Sobrevida
5.
Rofo ; 156(4): 346-52, 1992 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-1571516

RESUMO

Muscle metabolism was measured in 7 patients with arterial occlusive disease and symptoms of intermittent claudication both before and after percutaneous vascular neurolysis by means of dynamic 31P-MR spectroscopy. Phosphorus spectra of the involved calf muscles were determined before, during and after defined treadmill exercise. In addition to pH values the phosphocreatine content was measured during activity and recovery phases. There was close correlation in these patients between the increase in claudication distance and more rapid regeneration of phosphocreatine following neurolysis. However, none of the patients achieved normal values of phosphate metabolism. By means of the non-invasive 31P-MR spectroscopy it was possible for the first time to demonstrate the biochemical changes associated with neurolytic lumbar sympathetic blockade.


Assuntos
Arteriopatias Oclusivas/metabolismo , Espectroscopia de Ressonância Magnética , Músculos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Metabolismo Energético , Teste de Esforço , Feminino , Humanos , Claudicação Intermitente/metabolismo , Perna (Membro) , Espectroscopia de Ressonância Magnética/instrumentação , Espectroscopia de Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Radioisótopos de Fósforo
6.
J Chromatogr ; 545(2): 445-60, 1991 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-1885696

RESUMO

The analysis of barbiturates in human serum (or plasma) and urine by high-performance capillary electrophoresis-electrokinetic capillary chromatography with on-column fast-scanning multi-wavelength detection is discussed. The use of a buffer of ca. pH 8 and containing sodium dodecyl sulphate provides a medium suitable for fast and high-resolution separations of barbiturates. Seven barbiturates are characterized by their retention and absorption spectra between 195 and 320 nm. Comparison of these computer-stored data with those of unknown samples is shown to allow the identification of barbiturates in samples of patients undergoing pharmacotherapy and in toxicological urine and serum specimens. Three-dimensional electropherograms provide reliable information on the requirement and suitability of sample pretreatment procedures. With urine, extraction of barbiturates prior to analysis is necessary. With human serum several barbiturates, including phenobarbital, are shown to elute in an interference-free window in front of uric acid and the proteins, allowing these substances to be determined by direct sample injection. The need for multi-wavelength detection over a relatively wide wavelength range as a means of peak confirmation in electrokinetic capillary analyses is demonstrated and limitations of this technique for compounds with similar retention behaviour and absorption spectra are discussed.


Assuntos
Barbitúricos/análise , Cromatografia/métodos , Eletroforese/métodos , Barbitúricos/sangue , Barbitúricos/urina , Humanos
7.
Rofo ; 153(2): 204-8, 1990 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-2168078

RESUMO

31P-MR spectroscopy was performed in 12 patients with focal and diffuse liver disease and in ten normal controls, using surface coils. Results so far show a significantly increased concentration of PME/beta-ATP and of PDE/beta-ATP in patients with liver metastases and in one patient with hepatic involvement by malignant lymphoma. The spectra of liver cirrhosis and fatty livers showed no characteristic changes.


Assuntos
Hepatopatias/diagnóstico , Espectroscopia de Ressonância Magnética/métodos , Adulto , Idoso , Diagnóstico Diferencial , Humanos , Fígado/patologia , Espectroscopia de Ressonância Magnética/instrumentação , Pessoa de Meia-Idade , Radioisótopos de Fósforo
10.
Pathol Biol (Paris) ; 36(2): 121-6, 1988 Feb.
Artigo em Francês | MEDLINE | ID: mdl-3279379

RESUMO

Cultured human epithelia obtained from epidermal cells in vitro were used to assay the activity of staphylococcal epidermolytic toxin and develop an in vitro experimental model for the staphylococcal scalded skin syndrome. Human epidermal cells were grown from single epidermal cell suspensions obtained through trypsinization of adult normal skin into multilayered epithelia (with a basal cell layer, several intermediate and one or two upper layers) on mouse 3T3 feeder cells. First passage cultures were incubated with exfoliative toxin A from phage Group II staphylococci at various concentrations in DMEM. They were examined at various time intervals by direct microscopic and histological examination of respectively the culture plates or the epidermal sheets after their detachment from the plates with dispase grad II. A total exfoliation could be obtained at 24 hour at concentrations of Img and 500 micrograms/ml, only local areas of epidermolysis noted at 100 micrograms/ml. The intraepithelial separation was noted to occur between the basal layer and the lowest intermediate layer. No exfoliation could be observed at lower concentrations. Up to 4-5 hours few changes were evident, but at this time small areas of epidermolysis developed. With exfoliatin 100 micrograms/ml, intraepidermal blisters were clearly visible, occurring either between the basal cells and the lowest intermediate layer or between the first two intermediate cell layers. At the ultrastructural level, desmosomes were sparse and altered, with enlargement of the intercellular spaces and condensation of tonofilaments. These data indicate that human epidermal cell cultures, although their differentiation in culture only mimics what occurs in vivo, can be used as an in vitro model of the staphylococcal TEN to further investigate the site of action of such a toxin and the cellular mechanism responsible for the syndrome.


Assuntos
Toxinas Bacterianas/farmacologia , Epiderme/patologia , Exfoliatinas/farmacologia , Síndrome da Pele Escaldada Estafilocócica/patologia , Infecções Cutâneas Estafilocócicas/patologia , Adulto , Células Cultivadas/efeitos dos fármacos , Epiderme/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Epitélio/patologia , Feminino , Humanos , Masculino
11.
Gene ; 47(2-3): 269-77, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-2951300

RESUMO

The structural gene encoding cyclodextrin-glycosyltransferase of Klebsiella pneumoniae strain M5a1 was cloned; it is expressed both in Escherichia coli and in K. pneumoniae and the gene product is secreted into the extracellular space. Determination of the nucleotide sequence revealed an open reading frame coding for a single polypeptide of 655 amino acid (aa) residues. The enzyme is synthesized as a precursor with an N-terminal signal peptide of 30 aa residues, which is proteolytically processed between two alanine residues during export. The primary structure of CGT bears homology with the sequences of amylases from both prokaryotic and eukaryotic origins.


Assuntos
Genes Bacterianos , Glucosiltransferases/genética , Klebsiella pneumoniae/genética , Sequência de Bases , Clonagem Molecular , DNA Bacteriano/genética , Escherichia coli/enzimologia , Escherichia coli/genética , Regulação da Expressão Gênica , Genes , Glucosiltransferases/biossíntese , Klebsiella pneumoniae/enzimologia , alfa-Amilases/genética
12.
Gene ; 19(2): 231-4, 1982 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6293932

RESUMO

A new plasmid cloning vector (pHE3) is described carrying dominant p-fluorophenylalanine-sensitivity (pheS) and chloramphenicol-resistance markers. This vector is used in combination with a p-fluorophenylalanine-resistant Escherichia coli recipient (strain RR28). Foreign DNA can be cloned into pHE3 leading to insertional inactivation of pheS. Transformation of RR28, and plating on minimal medium with chloramphenicol plus p-fluorophenylalanine (pfp) directly selects for colonies containing recombinant DNA.


Assuntos
Clonagem Molecular , DNA Recombinante/metabolismo , Escherichia coli/genética , Genes Dominantes , Enzimas de Restrição do DNA , Escherichia coli/efeitos dos fármacos , Plasmídeos , Transformação Genética , p-Fluorfenilalanina/farmacologia
16.
Microbios ; 18(71): 59-68, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-24797

RESUMO

Transport of L-glycine by the haustorial mycoparasite Tieghemiomyces parasiticus grown in axenic culture was investigated using endogenously metabolizing cells. Transport occurred against a concentration gradient and required the expenditure of energy supplied by metabolic reactions that were inhibited by catalytic amounts of sodium azide and 2,4-dinitrophenol. The process exhibited both pH and temperature dependence with optima at pH 4 and 35 degrees C, respectively. The energy of activation and Q10 for transport were calculated to be 18,227 cal/mole and 2.82 respectively, between 20 and 30 degrees C. The kinetics of the system were consistent with a mechanism of transport that depended upon a finite number of sites on the cell surface and had a Kt of 1.46 x 10(-5) M. The system for L-glycine transport lacked sterospecificity and was most inhibited in the presence of other neutral amino acids while less inhibition was observed in the presence of the acidic and basic amino acids. These results suggest that L-glycine transport in this mycoparasite occurs by an energy dependent, protein-mediated process characteristic of active transport.


Assuntos
Fungos/metabolismo , Glicina/metabolismo , Mucorales/metabolismo , Aminoácidos/farmacologia , Azidas/farmacologia , Transporte Biológico , Permeabilidade da Membrana Celular , Meios de Cultura , Dinitrofenóis/farmacologia , Vida Livre de Germes , Concentração de Íons de Hidrogênio , Cinética , Sódio/farmacologia , Temperatura , Fatores de Tempo
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