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1.
Gen Comp Endocrinol ; 354: 114542, 2024 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-38685391

RESUMEN

The follicle-stimulating hormone receptor (FSHR) and luteinizing hormone receptor (LHR) in cloudy catshark were cloned, and recombinant FSHR and LHR were expressed for characterization. Ventral lobe extract (VLE) from the pituitary contains homologous FSH and LH, and it stimulated the cAMP signaling of FSHR and LHR dose-dependently. Two transcript variants of LHR (LHR-L with exon 10 and LHR-S without) were identified, and LHR-S was the dominant form with higher basal cAMP activity without VLE stimulation. Among various developmental stages of follicles, FSHR expression was mainly associated with the pre-vitellogenic and early white follicles. When follicles were recruited into vitellogenesis, the expression of FSHR decreased while of LHR was upregulated reciprocally, suggesting that LHR may also be responsible for the control of vitellogenesis in chondrichthyans. The expression of LHR-L was upregulated among maturing follicles before ovulation, indicating LHR-L could have a specific role in receiving the LH surge signal for final maturation. Plasma LH-like activity was transiently increased prior to the progesterone (P4)-surge and testosterone-drop at the beginning of P4-phase, supporting a pituitary control of follicle-maturation via LH signaling in chondrichthyans. The expression of follicular LHR was downregulated during the P4-phase when LH-like activity was high, indicating that the LH-dependent downregulation of LHR is conserved in chondrichthyans as it is in other vertebrate lineages. (213 words).


Asunto(s)
Receptores de HFE , Receptores de HL , Animales , Receptores de HL/metabolismo , Receptores de HL/genética , Femenino , Receptores de HFE/metabolismo , Receptores de HFE/genética , Hormona Luteinizante/metabolismo , Hormona Folículo Estimulante/metabolismo , Peces/metabolismo , Peces/genética , Folículo Ovárico/metabolismo
2.
Kyobu Geka ; 77(4): 256-261, 2024 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-38644171

RESUMEN

A 60-year old woman, sandwiched between two boats was brought to our hospital with severe respiratory failure. She was in pre-shock and there was extensive cutaneous emphysema from the face to abdomen. She required respirator support and bilateral chest tubes for hemopneumothorax. On the patient's 3rd hospital day, she received venovenous extracorporeal membrance oxgenation( ECMO) due to sudden ventilatory failure. The bronchofiberscopy revealed complete disruption of the left main bronchus and occlusion of the right one owing to blood clot and sputum. Because of significant destruction of the left main bronchus, we didn't attempt bronchoplasty, and performed left pneumonectomy under veno-venous (VV)-ECMO. The postoperative course was uneventful, and she was discharged after 30 days with satisfactory outcome.


Asunto(s)
Bronquios , Oxigenación por Membrana Extracorpórea , Neumonectomía , Humanos , Femenino , Persona de Mediana Edad , Bronquios/cirugía
3.
Phys Rev Lett ; 129(22): 223401, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36493443

RESUMEN

We report the realization of a Bose-Einstein condensate of europium atoms, which is a strongly dipolar species with unique properties, a highly symmetric [Xe]4f^{7}6s^{2} ^{8}S_{7/2} electronic ground state and a hyperfine structure. By means of evaporative cooling in a crossed optical dipole trap, we produce a condensate of ^{151}Eu containing up to 5×10^{4} atoms. We estimate the scattering length of ^{151}Eu to be a_{s}=110(4) a_{B} after comparing the velocities of expansion of condensates to different orientations of the atomic magnetic moments, where a_{B} is the Bohr radius. We observe deformation of the condensate in the vicinity of the Feshbach resonance at 1.32 G with a width of 10 mG.


Asunto(s)
Frío , Europio , Pinzas Ópticas , Transición de Fase , Vibración
4.
Nat Commun ; 11(1): 966, 2020 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-32075971

RESUMEN

Titanium oxide materials have multiple functions such as photocatalytic and photovoltaic effects. Ferroelectrics provide access to light energy conversion that delivers above-bandgap voltages arising from spatial inversion symmetry breaking, whereas their wide bandgap leads to poor absorption of visible light. Bandgap narrowing offers a potential solution, but this material modification suppresses spontaneous polarization and, hence, sacrifices photovoltages. Here, we report successive-redox mediated ferrophotovoltaics that exhibit a robust visible-light response. Our single-crystal experiments and ab initio calculations, along with photo-luminescence analysis, demonstrate that divalent Fe2+ and trivalent Fe3+ coexisted in a prototypical ferroelectric barium titanate BaTiO3 introduce donor and acceptor levels, respectively, and that two sequential Fe3+/Fe2+ redox reactions enhance the photogenerated power not only under visible light but also at photon energies greater than the bandgap. Our approach opens a promising route to the visible-light activation of photovoltaics and, potentially, of photocatalysts.

5.
Sci Rep ; 5: 14741, 2015 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-26443381

RESUMEN

The photovoltaic (PV) effect in polar materials offers great potential for light-energy conversion that generates a voltage beyond the bandgap limit of present semiconductor-based solar cells. Ferroelectrics have received renewed attention because of the ability to deliver a high voltage in the presence of ferroelastic domain walls (DWs). In recent years, there has been considerable debate over the impact of the DWs on the PV effects, owing to lack of information on the bulk PV tensor of host ferroelectrics. In this article, we provide the first direct evidence of an unusually large PV response induced by ferroelastic DWs-termed 'DW'-PV effect. The precise estimation of the bulk PV tensor in single crystals of barium titanate enables us to quantify the giant PV effect driven by 90° DWs. We show that the DW-PV effect arises from an effective electric field consisting of a potential step and a local PV component in the 90° DW region. This work offers a starting point for further investigation into the DW-PV effect of alternative systems and opens a reliable route for enhancing the PV properties in ferroelectrics based on the engineering of domain structures in either bulk or thin-film form.

6.
Rev Sci Instrum ; 86(7): 073110, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26233359

RESUMEN

We developed a high-power laser system at a wavelength of 399 nm for laser cooling of ytterbium atoms with ultraviolet laser diodes. The system is composed of an external cavity laser diode providing frequency stabilized output at a power of 40 mW and another laser diode for amplifying the laser power up to 220 mW by injection locking. The systematic method for optimization of our injection locking can also be applied to high power light sources at any other wavelengths. Our system does not depend on complex nonlinear frequency-doubling and can be made compact, which will be useful for providing light sources for laser cooling experiments including transportable optical lattice clocks.

7.
Phys Rev Lett ; 110(16): 163602, 2013 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-23679601

RESUMEN

We demonstrate unconditional quantum-noise suppression in a collective spin system via feedback control based on quantum nondemolition measurement. We perform shot-noise limited collective spin measurements on an ensemble of 3.7×10(5) laser-cooled (171)Yb atoms in their spin-1/2 ground states. Correlation between two sequential quantum nondemolition measurements indicates -0.80(-0.12)(+0.11) dB quantum-noise suppression in a conditional manner. Our feedback control successfully converts the conditional quantum-noise suppression into the unconditional one without significant loss of the noise reduction level.

9.
Phys Rev Lett ; 106(15): 157002, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21568603

RESUMEN

Transport properties of a superconductor-semiconductor-superconductor (Su-Sm-Su) junction with superlattice structure are investigated. Differential resistance as a function of voltage shows oscillatory behavior under the irradiation of radio-frequency (rf) waves with the specific frequency of 1.77 GHz regardless of the superconducting materials and the junction geometries. Experimental data are quantitatively explained in terms of the coupling of superconducting quasiparticles with long-wavelength acoustic phonons indirectly excited by the rf waves. We propose that the strong coupling causes the formation of novel composite particles, Andreev polarons.

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