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1.
Nature ; 632(8026): 775-781, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39169248

RESUMO

Superconductivity involving finite-momentum pairing1 can lead to spatial-gap and pair-density modulations, as well as Bogoliubov Fermi states within the superconducting gap. However, the experimental realization of their intertwined relations has been challenging. Here we detect chiral kagome superconductivity modulations with residual Fermi arcs in KV3Sb5 and CsV3Sb5 using normal and Josephson scanning tunnelling microscopy down to 30 millikelvin with a resolved electronic energy difference at the microelectronvolt level. We observe a U-shaped superconducting gap with flat residual in-gap states. This gap shows chiral 2a × 2a spatial modulations with magnetic-field-tunable chirality, which align with the chiral 2a × 2a pair-density modulations observed through Josephson tunnelling. These findings demonstrate a chiral pair density wave (PDW) that breaks time-reversal symmetry. Quasiparticle interference imaging of the in-gap zero-energy states reveals segmented arcs, with high-temperature data linking them to parts of the reconstructed vanadium d-orbital states within the charge order. The detected residual Fermi arcs can be explained by the partial suppression of these d-orbital states through an interorbital 2a × 2a PDW and thus serve as candidate Bogoliubov Fermi states. In addition, we differentiate the observed PDW order from impurity-induced gap modulations. Our observations not only uncover a chiral PDW order with orbital selectivity but also show the fundamental space-momentum correspondence inherent in finite-momentum-paired superconductivity.

2.
Vasc Endovascular Surg ; 58(5): 498-504, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38252516

RESUMO

OBJECTIVE: To evaluate the application of different uterine artery embolization procedures under balloon occlusion of the abdominal aorta in patients with Placenta Accreta Spectrum (PAS) undergoing cesarean section. MATERIALS AND METHODS: A retrospective analysis was performed on clinical data from 72 patients who underwent uterine artery embolization for hemostasis during cesarean section with PAS. The patients were divided into two groups according to the embolization method used during surgery: group A (n = 43) underwent uterine artery embolization by withdrawing the balloon and inserting a Cobra catheter into the uterine artery for embolization, while group B (n = 29) underwent uterine artery embolization with a Cobra catheter inserted via contralateral puncture of the femoral artery and balloon occlusion. General information, surgical data, and postoperative recovery were compared between the 2 groups. RESULTS: The bleeding and transfusion volumes were lower in group B than in group A and the differences between the 2 groups were statistically significant. There were no significant differences in surgical duration, number of embolized vessels, length of hospital stay, postoperative complications, or menstrual recovery between the 2 groups. CONCLUSION: For patients with PAS undergoing cesarean section, uterine artery embolization for hemostasis is preferably performed by inserting a Cobra catheter via contralateral puncture of the femoral artery under abdominal aortic balloon occlusion.


Assuntos
Aorta Abdominal , Oclusão com Balão , Cesárea , Placenta Acreta , Hemorragia Pós-Parto , Embolização da Artéria Uterina , Humanos , Feminino , Embolização da Artéria Uterina/efeitos adversos , Estudos Retrospectivos , Placenta Acreta/terapia , Placenta Acreta/diagnóstico por imagem , Resultado do Tratamento , Cesárea/efeitos adversos , Adulto , Gravidez , Aorta Abdominal/diagnóstico por imagem , Oclusão com Balão/efeitos adversos , Hemorragia Pós-Parto/terapia , Hemorragia Pós-Parto/etiologia , Perda Sanguínea Cirúrgica/prevenção & controle , Fatores de Tempo , Punções , Artéria Femoral/diagnóstico por imagem , Cateterismo Periférico/efeitos adversos , Transfusão de Sangue
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