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1.
BMC Pregnancy Childbirth ; 23(1): 171, 2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-36915067

RESUMEN

BACKGROUND: To assess the prevalence, risk factors, clinical characteristics of Acute fatty liver of pregnancy (AFLP) patients, and outcomes of AFLP patients treated with plasma exchange (PE). METHODS: We retrospectively reviewed the AFLP patients admitted to the First Affiliated Hospital of Xi'an Jiaotong University and Xijing Hospital of Air Force Medical University from January 2012 to May 2022. Final prediction model for death among AFLP by means of stepwise backward elimination with p value < 0.05. Patients treated with and without PE were compared by propensity-matched cohort study. RESULTS: Two hundred ninety eight patients with the diagnosis of AFLP, and finally 290 patients were enrolled in the cohort study, 50 of whom (17.2%) were dead. Compared with AFLP patients alive, the dead of patients were more likely to be combined encephalopathy (p < 0.01), postpartum hemorrhage (p < 0.01), and found significantly higher frequency of fetal distress (p = 0.04), fetal death (p < 0.01). we developed a predicted probability value and with an area under the receiver operating characteristics (ROC) curve of 0.94 (95%CI 0.87 to 1.00), indicating AFLP patients' death. The patients treated with PE had a significantly lower 60-day mortality rate (OR 0.42, 95% CI 0.29 to 2.64, p = 0.04), and significantly shorter duration of hospital-free days at day 28 (p = 0.01). CONCLUSIONS: In conclusion, our study indicated that liver function were risk factors for maternal mortality, and PE was a protective factor for maternal 60-day mortality and hospital-free days at day 28 in AFLP patients.


Asunto(s)
Hígado Graso , Complicaciones del Embarazo , Embarazo , Femenino , Humanos , Intercambio Plasmático , Estudios Retrospectivos , Estudios de Cohortes , Hígado Graso/epidemiología , Hígado Graso/terapia , Hígado Graso/diagnóstico , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/terapia , Complicaciones del Embarazo/diagnóstico
2.
Phys Chem Chem Phys ; 24(36): 21612-21616, 2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-35920753

RESUMEN

An ultra-broadband polarization-insensitive perfect absorber for the 400-4000 nm spectral range is proposed and studied. The absorber is composed of a dielectric film and a phase change material film sandwiched between a bismuth square ring array and a continuous bismuth mirror. Greater than 94% absorptivity across the wavelength range of 400-4000 nm and an averaged absorptivity of about 97% can be achieved. The physical origin results from the mixed effect of guided mode resonance (GMR), cavity resonance (CR) and surface plasmon resonance (SPR). In addition, such a property is maintained excellent in a very large viewing angle range. Furthermore, the proposed scheme exhibits certain geometrical parameter tolerance, which is beneficial for practical fabrication with low cost. Finally, the potential application of the solar cells is investigated as an illustration. The designed metamaterial absorber will find promising applications in solar cells, thermo-photovoltaics and detection.

3.
Nanomaterials (Basel) ; 12(4)2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-35215038

RESUMEN

Dimers made of plasmonic particles support strong field enhancements but suffer from large absorption losses, while low-loss dielectric dimers are limited by relatively weak optical confinement. Hybrid dimers could utilize the advantages of both worlds. Here, we propose a hybrid nanoantenna that contains a dimer of core-dual shell nanoparticles known as the metal-dielectric-metal (MDM) structure. We discovered that the hybrid dimer sustained unidirectional forward scattering, which resulted in a nearly ideal Kerker condition in the frequency close to the resonance peak of the dimer due to enhancing the amplitude of the induced high-order electric multiples in the gap and effectively superimposing them with magnetic ones, which respond to the excitation of the plane wave in the dielectric layer of the dimer. Furthermore, when an electric quantum emitter is coupled to the dimer, our study shows that the optimal hybrid dimer simultaneously possesses high radiation directivity and low-loss features, which illustrates a back-to-front ratio of radiation 53 times higher than that of the pure dielectric dimer and an average radiation efficiency 80% higher than that of the pure metallic dimer. In addition, the unique structures of the hybrid hexamer direct almost decrease 75% of the radiation beamwidth, hence heightening the directivity of the nanoantenna based on a hybrid dimer.

4.
Nanomaterials (Basel) ; 12(12)2022 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-35745422

RESUMEN

Dielectric-metal nanostructures have lately emerged as one of the most promising approaches to modulating light at the optical frequency. Their remarkable electric and magnetic resonances give them a one-of-a-kind ability to augment local field enhancements with negligible absorption losses. Here, we propose a hybrid metal-dielectric-metal (MDM) nanoantenna that contains a dimer of three-layers of shell nanoparticles. In addition, we only theoretically and numerically show the optical properties of the hybrid dimer nanoantenna. We found that the nanoantenna sustained unidirectional forward scattering with narrow beamwidth (30.9 deg) and strong scattering intensity (up to 5 times larger than the single MDM particle). Furthermore, when the hybrid asymmetric dimer was excited by the plane wave with different electric polarization directions, our findings revealed that the hybrid nanoantenna boosted the gap's electric near-field while also supporting unidirectional forward scattering. Finally, we analyzed the hybrid dimer with substrates of different materials. It supported strong electric high-order moments along the z-axis and x-axis in gaps between MDM nanoparticles and between MDM nanoparticles and the Ge substrate, owing to the intense displacement currents inside of the dielectric layer. We found that the local electric field of this MDM hybrid dimer nanoantenna with Ge substrate was well improved and attained 3325 v/m.

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