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1.
Nat Commun ; 15(1): 5816, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987273

RESUMO

The diverse applications of light-matter interactions in science and technology stem from the qualitatively distinct ways these interactions manifest, prompting the development of physical platforms that can interchange between regimes on demand. Bosonic cQED employs the light field of high-Q superconducting cavities coupled to nonlinear circuit elements, harnessing the rich dynamics of their interaction for quantum information processing. However, implementing fast switching of the interaction regime without deteriorating the cavity coherence is a significant challenge. We present an experiment that achieves this feat, combining nanosecond-scale frequency tunability of a transmon coupled to a cavity with lifetime of hundreds of microseconds. Our implementation affords a range of useful capabilities for quantum information processing; from fast creation of cavity Fock states using resonant interaction and interchanging tomography techniques at qualitatively distinct interaction regimes on the fly, to the suppression of unwanted cavity-transmon dynamics during idle evolution. By bringing flux tunability into the bosonic cQED toolkit, our work opens up the possibility to probe the full range of light-matter interaction dynamics within a single platform and provides valuable pathways towards robust and versatile quantum information processing.

2.
Artigo em Inglês | MEDLINE | ID: mdl-37269940

RESUMO

The neurotransmitter 5-hydroxytryptamine (5-HT, serotonin) plays an essential role in the regulation of neural activity via multiple receptors. Here, we investigated the functional role of serotoninergic input on the Dahlgren cell population in the caudal neurosecretory system (CNSS) of olive flounder. In this study, the effect of 5-HT on the firing activity of Dahlgren cells was explored in terms of changes in firing frequency and firing pattern using multicellular recording electrophysiology ex vivo, and the role of several 5-HT receptor subtypes in the regulation was determined. The results revealed that 5-HT increased the firing frequency in a concentration-dependent manner and altered the firing pattern of Dahlgren cells. The effect of 5-HT on the firing activity of Dahlgren cells was mediated through the 5-HT1A and 5-HT2B receptors, selective agonists of both receptors effectively increased the firing frequency of Dahlgren cells, and selective receptor antagonists could also effectively inhibit the increase in firing frequency caused by 5-HT. In addition, the mRNA levels of major signaling pathway-related genes, ion channels, and major secretion hormone genes were significantly upregulated in CNSS after treatment with 5-HT. These findings demonstrate that 5-HT acts as an excitatory neuromodulator on Dahlgren cells and enhances neuroendocrine activity in CNSS.


Assuntos
Linguado , Serotonina , Animais , Serotonina/farmacologia , Linguado/fisiologia , Sistemas Neurossecretores/fisiologia , Neurotransmissores
3.
Nat Commun ; 13(1): 4735, 2022 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-35961985

RESUMO

Molecular conformations induced by the rotation about single bonds play a crucial role in chemical transformations. Revealing the relationship between the conformations of chiral catalysts and the enantiodiscrimination is a formidable challenge due to the great difficulty in isolating the conformers. Herein, we report a chiral catalytic system composed of an achiral catalytically active unit and an axially chiral 1,1'-bi-2-naphthol (BINOL) unit which are connected via a C-O single bond. The two conformers of the catalyst induced by the rotation about the C-O bond, are determined via single-crystal X-ray diffraction and found to respectively lead to the formation of highly important axially chiral 1,1'-binaphthyl-2,2'-diamine (BINAM) and 2-amino-2'-hydroxy-1,1'-binaphthyl (NOBIN) derivatives in high yields (up to 98%), with excellent enantioselectivities (up to 98:2 e.r.) and opposite absolute configurations. The results highlight the importance of conformational dynamics of chiral catalysts in asymmetric catalysis.


Assuntos
Diaminas , Catálise , Cristalografia por Raios X , Diaminas/química , Conformação Molecular
4.
Sci Rep ; 10(1): 3093, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32080312

RESUMO

Quantum teleportation enables networking participants to move an unknown quantum state between the nodes of a quantum network, and hence constitutes an essential element in constructing large-sale quantum processors with a quantum modular architecture. Herein, we propose two protocols for teleporting qubits through an N-node quantum network in a highly-entangled box-cluster state or chain-type cluster state. The proposed protocols are systematically scalable to an arbitrary finite number N and applicable to arbitrary size of modules. The protocol based on a box-cluster state is implemented on a 14-qubit IBM quantum computer for N up to 12. To identify faithful networking teleportation, namely that the elements on real devices required for the networking teleportation process are all qualified for achieving teleportation task, we quantify quantum-mechanical processes using a generic classical-process model through which any classical strategies of mimicry of teleportation can be ruled out. From the viewpoint of achieving a genuinely quantum-mechanical process, the present work provides a novel toolbox consisting of the networking teleportation protocols and the criteria for identifying faithful teleportation for universal quantum computers with modular architectures and facilitates further improvements in the reliability of quantum-information processing.

5.
Org Lett ; 21(12): 4868-4872, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31188008

RESUMO

Although a range of transition-metal-catalyzed cross-coupling reactions of alkenes and alkynes have been developed to produce valuable conjugated dienes, extension of these reactions to iridium catalysis has yet to be demonstrated. The first iridium-catalyzed alkene-alkyne cross-coupling reactions have been realized under ligand- and additive-free conditions. A wide range of acrylamides and alkynes could be used as coupling partners, providing branched ( Z, Z)-butadiene skeletons with excellent site- and stereoselectivities. The utility of this approach is also demonstrated by preparative-scale and C-H functionalization of perillic and artemisic amides.

6.
J Immunol ; 191(9): 4611-8, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24078690

RESUMO

Innate lymphoid cells encompass a diverse array of lymphocyte subsets with unique phenotype that initiate inflammation and provide host defenses in specific microenvironments. In this study, we identify a rare human CD4(+)CD3(-) innate-like lymphoid population with high TNF expression that is enriched in blood from patients with rheumatoid arthritis. These CD4(+)CD3(-) cells belong to the T cell lineage, but the lack of AgR at the cell surface renders them nonresponsive to TCR-directed stimuli. By developing a culture system that sustains survival, we show that CD4(+)CD3(-) innate-like T cells display IL-7-dependent induction of surface lymphotoxin-αß, demonstrating their potential to modify tissue microenvironments. Furthermore, expression of CCR6 on the CD4(+)CD3(-) population defines a CD127(high) subset that is highly responsive to IL-7. This CD4(+)CD3(-) population is enriched in the peripheral blood from rheumatoid arthritis patients, suggesting a link to their involvement in chronic inflammatory disease.


Assuntos
Artrite Reumatoide/metabolismo , Complexo CD3/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Heterotrímero de Linfotoxina alfa1 e beta2/metabolismo , Fatores de Necrose Tumoral/metabolismo , Adulto , Idoso , Animais , Artrite Reumatoide/imunologia , Linfócitos T CD4-Positivos/imunologia , Linhagem Celular , Feminino , Células HEK293 , Proteínas de Homeodomínio/genética , Humanos , Inflamação , Interleucina-7/metabolismo , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Heterotrímero de Linfotoxina alfa1 e beta2/imunologia , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Receptores CCR6/metabolismo
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