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1.
Nature ; 607(7917): 69-73, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35794269

RESUMEN

Quantum networks promise to provide the infrastructure for many disruptive applications, such as efficient long-distance quantum communication and distributed quantum computing1,2. Central to these networks is the ability to distribute entanglement between distant nodes using photonic channels. Initially developed for quantum teleportation3,4 and loophole-free tests of Bell's inequality5,6, recently, entanglement distribution has also been achieved over telecom fibres and analysed retrospectively7,8. Yet, to fully use entanglement over long-distance quantum network links it is mandatory to know it is available at the nodes before the entangled state decays. Here we demonstrate heralded entanglement between two independently trapped single rubidium atoms generated over fibre links with a length up to 33 km. For this, we generate atom-photon entanglement in two nodes located in buildings 400 m line-of-sight apart and to overcome high-attenuation losses in the fibres convert the photons to telecom wavelength using polarization-preserving quantum frequency conversion9. The long fibres guide the photons to a Bell-state measurement setup in which a successful photonic projection measurement heralds the entanglement of the atoms10. Our results show the feasibility of entanglement distribution over telecom fibre links useful, for example, for device-independent quantum key distribution11-13 and quantum repeater protocols. The presented work represents an important step towards the realization of large-scale quantum network links.

2.
Small ; 20(27): e2310736, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38282175

RESUMEN

2D alloy-based anodes show promise in potassium-ion batteries (PIBs). Nevertheless, their low tap density and huge volume expansion cause insufficient volumetric capacity and cycling stability. Herein, a 3D highly dense encapsulated architecture of 2D-Bi nanosheets (HD-Bi@G) with conducive elastic networks and 3D compact encapsulation structure of 2D nano-sheets are developed. As expected, HD-Bi@G anode exhibits a considerable volumetric capacity of 1032.2 mAh cm-3, stable long-life span with 75% retention after 2000 cycles, superior rate capability of 271.0 mAh g-1 at 104 C, and high areal capacity of 7.94 mAh cm-2 (loading: 24.2 mg cm-2) in PIBs. The superior volumetric and areal performance mechanisms are revealed through systematic kinetic investigations, ex situ characterization techniques, and theorical calculation. The 3D high-conductivity elastic network with dense encapsulated 2D-Bi architecture effectively relieves the volume expansion and pulverization of Bi nanosheets, maintains internal 2D structure with fast kinetics, and overcome sluggish ionic/electronic diffusion obstacle of ultra-thick, dense electrodes. The uniquely encapsulated 2D-nanosheet structure greatly reduces K+ diffusion energy barrier and accelerates K+ diffusion kinetics. These findings validate a feasible approach to fabricate 3D dense encapsulated architectures of 2D-alloy nanosheets with conductive elastic networks, enabling the design of ultra-thick, dense electrodes for high-volumetric-energy-density energy storage.

3.
Small ; : e2400304, 2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38881255

RESUMEN

Developing cost-effective, durable bifunctional electrocatalysts is crucial but remains challenging due to slow hydrogen/oxygen evolution reaction (HER/OER) kinetics in water electrolysis. Herein, a combined engineering strategy of phosphorous vacancy (Vp) and spontaneous built-in electric field (BIEF) is proposed to design novel highly-conductive Co-doped MoP@MXene heterostructures with phosphorous vacancy (Vp-Co-MoP@MXene). Wherein, Co doping regulates the surface electronic structure and charge re-distribution of MoP, Vp induces more defects and active sites, while BIEF accelerates the interfacial charge transfer rate between Vp-Co-MoP and MXene. Therefore, the synergistic integration of Vp-Co-MoP/MXene efficiently decreases activation energy and kinetic barrier, thus promoting its intrinsically catalytic activity and structural stability. Consequently, the Vp-Co-MoP@MXene catalyst displays low overpotentials of 102.3/196.5 and 265.0/320.0 mV at 10/50 mA cm-2 for HER and OER, respectively. Notably, two-electrode electrolyzers with the Vp-Co-MoP@MXene bifunctional catalysts to achieve 10/50 mA cm-2, only need low-cell voltages of 1.57/1.64 V in alkaline media. Besides, experimental and theoretical results confirm that the hetero-structure effectively reduces hydrogen adsorption free energy and rate-determining-step energy barrier of OER intermediates, thereby greatly boosting its intrinsically catalytic activity. This work verifies an effective strategy to fabricate efficient non-precious bifunctional electro-catalysts for water splitting via combination engineering of phosphorous vacancy, cation doping, and BIEF.

4.
Phys Rev Lett ; 124(1): 010509, 2020 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-31976739

RESUMEN

We report the direct characterization of energy-time entanglement of narrow-band biphotons produced from spontaneous four-wave mixing in cold atoms. The Stokes and anti-Stokes two-photon temporal correlation is measured by single-photon counters with nanosecond temporal resolution, and their joint spectrum is determined by using a narrow linewidth optical cavity. The energy-time entanglement is verified by the joint frequency-time uncertainty product of 0.063±0.0044, which does not only violate the separability criterion but also satisfies the continuous variable Einstein-Podolsky-Rosen steering inequality.

5.
Phys Rev Lett ; 123(19): 190402, 2019 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-31765181

RESUMEN

The measurement of a quantum state wave function not only acts as a fundamental part in quantum physics but also plays an important role in developing practical quantum technologies. Conventional quantum state tomography has been widely used to estimate quantum wave functions, which usually requires complicated measurement techniques. The recent weak-value-based quantum measurement circumvents this resource issue but relies on an extra pointer space. Here, we theoretically propose and then experimentally demonstrate a direct and efficient measurement strategy based on a δ-quench probe: by quenching its complex probability amplitude one by one (δ quench) in the given basis, we can directly obtain the quantum wave function of a pure ensemble by projecting the quenched state onto a postselection state. We confirm its power by experimentally measuring photonic complex temporal wave functions. This new method is versatile and can find applications in quantum information science and engineering.

6.
Int J Biol Sci ; 20(5): 1947-1964, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38481800

RESUMEN

Kirsten rat sarcoma viral oncogene homolog (KRAS) is an oncogene implicated in the pathophysiology of many cancers. Increasing evidence shows that KRAS mutation is correlated with poor prognosis in numerous cancers, including colorectal cancer (CRC), breast cancer, and melanoma. KRAS also participates in regulating the CRC microenvironment. However, the direct and indirect therapeutic targets of KRAS in CRC have not been identified; thus, elucidating the mechanisms and interactions between KRAS and the tumor microenvironment (TME) in-depth is paramount. Herein, we present some of the major roles KRAS plays in shaping the heterogeneity of the TME and propose a potential strategy for targeting the downstream components of the KRAS signaling pathway and the TME in CRC.


Asunto(s)
Neoplasias Colorrectales , Proteínas Proto-Oncogénicas p21(ras) , Humanos , Proteínas Proto-Oncogénicas p21(ras)/genética , Microambiente Tumoral/genética , Mutación/genética , Transducción de Señal/genética , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología
7.
Adv Mater ; 36(11): e2308447, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38091528

RESUMEN

The inferior cycling stabilities or low capacities of 2D Sb or Bi limit their applications in high-capacity and long-stability potassium/lithium-ion batteries (PIBs/LIBs). Therefore, integrating the synergy of high-capacity Sb and high-stability Bi to fabricate 2D binary alloys is an intriguing and challenging endeavor. Herein, a series of novel 2D binary SbBi alloys with different atomic ratios are fabricated using a simple one-step co-replacement method. Among these fabricated alloys, the 2D-Sb0.6 Bi0.4 anode exhibits high-capacity and ultra-stable potassium and lithium storage performance. Particularly, the 2D-Sb0.6 Bi0.4 anode has a high-stability capacity of 381.1 mAh g-1 after 500 cycles at 0.2 A g-1 (≈87.8% retention) and an ultra-long-cycling stability of 1000 cycles (0.037% decay per cycle) at 1.0 A g-1 in PIBs. Besides, the superior lithium and potassium storage mechanism is revealed by kinetic analysis, in-situ/ex-situ characterization techniques, and theoretical calculations. This mainly originates from the ultra-stable structure and synergistic interaction within the 2D-binary alloy, which significantly alleviates the volume expansion, enhances K+ adsorption energy, and decreases the K+ diffusion energy barrier compared to individual 2D-Bi or 2D-Sb. This study verifies a new scalable design strategy for creating 2D binary (even ternary) alloys, offering valuable insights into their fundamental mechanisms in rechargeable batteries.

8.
Andrology ; 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39189935

RESUMEN

BACKGROUND: Oligoasthenoteratozoospermia (OAT) is a common cause of male infertility, of which the causes remain largely unknown. Recently, BCORL1 was identified as a contributor to male infertility from non-obstructive azoospermia (NOA) to OAT. OBJECTIVES: To identify novel and hotspot variants in BCORL1 from infertile men with OAT and reveal their outcomes of assisted reproductive treatments (ARTs). MATERIALS AND METHODS: Forty-six infertile men characterized by OAT were recruited from 2017 to 2022. Variants in OAT patients were identified by whole-exome sequencing (WES) and verified by Sanger sequencing. Papanicolaou staining was used for sperm morphology analysis. Pathogenicity of BCORL1 variants were analyzed by bioinformatics analysis, and further confirmed in vitro by using recombinant plasmids and cells. Meanwhile, ARTs were performed on these patients to investigate the appropriate clinical treatment strategy. RESULTS: We identified a novel hemizygous missense variant (NM_021946: c.G4171A; p.G1391R) and a recurrent variant (NM_021946: c.T2615G; p.V872G) in BCORL1 from four OAT patients. Notably, routine semen assessment and Papanicolaou staining revealed a special OAT phenotype of patients with BCORL1 variants, whose rare mature sperm characterized by acephalic and abnormal acrosome. Pathogenicity analysis showed the interaction between BCORL1 with histone deacetylases (HDACs) were disrupted after variance, accompanied with epigenetic alterations and finally the orderly transcriptions of spermatogenetic genes were interfering. Besides, clinical record presented the poor outcomes of ARTs in these patients with BCORL1 variants. DISCUSSION AND CONCLUSIONS: Our findings further expand the variant spectrum of BCORL1 related to OAT, and provide new evidences that BCORL1 acts as an important transcriptional regulator, participating in epigenetic regulation and directing the expression of key genes throughout spermatogenesis. The outcomes of ARTs will facilitate the genetic counseling and clinical treatment of infertile men with BCORL1 variants in the future.

9.
Mol Neurobiol ; 58(6): 2803-2811, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33501626

RESUMEN

Traumatic brain injury (TBI) has both high morbidity and mortality rates and can negatively influence physical and mental health, while also causing extreme burden to both individual and society. Hitherto, there is no effective treatment for TBI because of the complexity of the brain anatomy and physiology. Currently, management strategies mainly focus on controlling inflammation after TBI. Tumor necrotizing factor alpha (TNF-α) plays a crucial role in neuroinflammation post-TBI. TNF-α acts as the initiator of downstream inflammatory signaling pathways, and its activation can trigger a series of inflammatory reactions. Infliximab is a monoclonal anti-TNF-α antibody that reduces inflammation. Herein, we review the latest findings pertaining to the role of TNF-α and infliximab in TBI. We seek to present a comprehensive clinical application prospect of infliximab in TBI and, thus, discuss potential strategies of infliximab in treating TBI.


Asunto(s)
Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Infliximab/uso terapéutico , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/patología , Ensayos Clínicos como Asunto , Humanos , Inflamación/complicaciones , Inflamación/patología , Infliximab/farmacología
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