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1.
Phys Rev Lett ; 131(4): 041403, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37566847

RESUMO

In this Letter, we present the design and performance of the frequency-dependent squeezed vacuum source that will be used for the broadband quantum noise reduction of the Advanced Virgo Plus gravitational-wave detector in the upcoming observation run. The frequency-dependent squeezed field is generated by a phase rotation of a frequency-independent squeezed state through a 285 m long, high-finesse, near-detuned optical resonator. With about 8.5 dB of generated squeezing, up to 5.6 dB of quantum noise suppression has been measured at high frequency while close to the filter cavity resonance frequency, the intracavity losses limit this value to about 2 dB. Frequency-dependent squeezing is produced with a rotation frequency stability of about 6 Hz rms, which is maintained over the long term. The achieved results fulfill the frequency dependent squeezed vacuum source requirements for Advanced Virgo Plus. With the current squeezing source, considering also the estimated squeezing degradation induced by the interferometer, we expect a reduction of the quantum shot noise and radiation pressure noise of up to 4.5 dB and 2 dB, respectively.

2.
J Opt Soc Am A Opt Image Sci Vis ; 35(2): 286-292, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29400877

RESUMO

We present closed and simple expressions of the spatial and angular Goos-Hänchen and Imbert-Fedorov shifts in terms of the second-order irradiance moments of a beam. Our results are applicable to a general totally polarized partially coherent beam. One of the main advantages of this formalism is that it can be applied directly from the knowledge of the cross-spectral density function and the polarization state without using any modal beam expansion. The obtained expressions allow understanding of the relationship between the global spatial characteristics of the incident beam and the experimented shifts in the reflected beam. Cosine-Gaussian Schell-model beams with rectangular symmetry are used to exemplify results.

3.
J Evol Biol ; 27(11): 2495-506, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25345665

RESUMO

Individual variation in the magnitude of inbreeding depression (ID) in plants and its association with phenotypic traits may have important consequences for mating system evolution. This association has been investigated only scarcely, and always considering traits functionally related to autogamy. Here, we explore the association between individual variation in ID and plant traits associated with pollinator attractiveness (related to plant size, corolla size and corolla shape) in two populations of Erysimum mediohispanicum (Brassicaceae). ID was calculated along the entire life cycle of the plants. In addition, we also explored the relationship between phenotypic traits and the individual levels of heterozygosity. We found significant associations between ID and corolla diameter and stalk height, being taller plants with larger corollas those undergoing a lower intensity of ID. Furthermore, we found a negative relationship between corolla diameter and heterozygosity, suggesting that plants with large flowers have purged their genetic load. Finally, we found a significant effect of corolla diameter on the intrapopulation genetic structure. All these findings suggest that plants with large flowers have secularly suffered frequent inbreeding in the study populations. Because corolla diameter is a trait frequently selected by pollinators in E. mediohispanicum, we believe that the observed relationship between this trait and ID could be mediated by pollinators, probably throughout an increasing in biparental inbreeding, geitonogamy or autogamy.


Assuntos
Erysimum/genética , Evolução Biológica , Erysimum/anatomia & histologia , Erysimum/fisiologia , Flores/anatomia & histologia , Flores/genética , Aptidão Genética , Heterozigoto , Endogamia , Fenótipo , Polinização/genética , Reprodução/genética , Seleção Genética , Autofertilização/genética
4.
Int Urol Nephrol ; 45(3): 869-78, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23065432

RESUMO

BACKGROUND: Acute kidney injury (AKI) requiring dialysis in critically ill patients is associated with an in-hospital mortality rate of 50-80 %. Extended daily hemodialysis (EHD) and high volume peritoneal dialysis (HVPD) have emerged as alternative modalities. METHODS: A double-center, randomized, controlled trial was conducted comparing EHD versus HVPD for the treatment for AKI in the intensive care unit (ICU). Four hundred and seven patients were randomized and 143 patients were analyzed. Principal outcome measure was hospital mortality, and secondary end points were recovery of renal function and metabolic and fluid control. RESULTS: There was no difference between the two groups in relation to median ICU stay [11 (5.7-20) vs. 9 (5.7-19)], recovery of kidney function (26.9 vs. 29.6 %, p = 0.11), need for chronic dialysis (9.7 vs. 6.5 %, p = 0.23), and hospital mortality (63.4 vs. 63.9 %, p = 0.94). The groups were different in metabolic and fluid control. Blood urea nitrogen (BUN), creatinine, and bicarbonate levels were stabilized faster in EHD group than in HVPD group. Delivered Kt/V and ultrafiltration were higher in EHD group. Despite randomization, there were significant differences between the groups in some covariates, including age, pre-dialysis BUN, and creatinine levels, biased in favor of the EHD. Using logistic regression to adjust for the imbalances in group assignment, the odds of death associated with HVPD was 1.4 (95 % CI 0.7-2.4, p = 0.19). A detailed investigation of the randomization process failed to explain the marked differences in patient assignment. CONCLUSIONS: Despite faster metabolic control and higher dialysis dose and ultrafiltration with EHD, this study provides no evidence of a survival benefit of EHD compared with HVPD. The limitations of this study were that the results were not presented according to the intention to treat and it did not control other supportive management strategies as nutrition support and timing of dialysis initiation that might influence outcomes in AKI.


Assuntos
Injúria Renal Aguda/terapia , Diálise Peritoneal/métodos , Diálise Renal/métodos , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/mortalidade , Idoso , Nitrogênio da Ureia Sanguínea , Brasil/epidemiologia , Creatinina/metabolismo , Feminino , Seguimentos , Mortalidade Hospitalar/tendências , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
5.
Aten Primaria ; 30(6): 357-62, 2002 Oct 15.
Artigo em Espanhol | MEDLINE | ID: mdl-12396941

RESUMO

OBJECTIVES: To study prevalence of pressure ulcers among functionally impaired patients in the community and evaluate risk factors associated with the development of pressure ulcers in these patients.Design. Cross-sectional, observational study. SETTING: Community dwellers served by the Primary Health Care Area of Rincón de la Victoria in Málaga.Participants. All patients included in the <> (n=178). METHODS: A questionnaire was developed to ascertain demographic and health characteristics. Risk factors were evaluated with the Modified Norton Scale. The outcome variable of interest was presence or absence of pressure ulcers, their location and grade. The denominator used for the calculation of the prevalence was the total of evaluated patients. Results. Prevalence of pressure ulcers in our Basic Health Area was 12.9%. The most important sociodemographic characteristic associated with the presence of pressure ulcers in these patients was the educational attainment of the caregiver. Health varaibles of the patient were also associated with the risk of developing ulcers. CONCLUSIONS: Results indicate the need of diagnostic protocols with standardised instruments and prevention plans to reduce pressure ulcers in the community. Longitudinal studies are needed to evaluate interventions in this area.


Assuntos
Úlcera por Pressão/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
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