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1.
Nature ; 613(7945): 656-661, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36653455

RESUMO

Domain-wall nanoelectronics is considered to be a new paradigm for non-volatile memory and logic technologies in which domain walls, rather than domains, serve as an active element. Especially interesting are charged domain walls in ferroelectric structures, which have subnanometre thicknesses and exhibit non-trivial electronic and transport properties that are useful for various nanoelectronics applications1-3. The ability to deterministically create and manipulate charged domain walls is essential to realize their functional properties in electronic devices. Here we report a strategy for the controllable creation and manipulation of in-plane charged domain walls in BiFeO3 ferroelectric films a few nanometres thick. By using an in situ biasing technique within a scanning transmission electron microscope, an unconventional layer-by-layer switching mechanism is detected in which ferroelectric domain growth occurs in the direction parallel to an applied electric field. Based on atomically resolved electron energy-loss spectroscopy, in situ charge mapping by in-line electron holography and theoretical calculations, we show that oxygen vacancies accumulating at the charged domain walls are responsible for the domain-wall stability and motion. Voltage control of the in-plane domain-wall position within a BiFeO3 film gives rise to multiple non-volatile resistance states, thus demonstrating the key functional property of being a memristor a few unit cells thick. These results promote a better understanding of ferroelectric switching behaviour and provide a new strategy for creating unit-cell-scale devices.

2.
Respiration ; 103(6): 295-316, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38498991

RESUMO

BACKGROUND: Lung tumors are prevalent malignancies associated with a high mortality rate, imposing significant medical and societal burdens. Although immunotherapy shows promise in improving survival, response rates are relatively modest. Thermal ablation can not only eliminate tumor cells directly but also enhance antitumor immunity response, thus manifesting a remarkable propensity to synergize with immunotherapy. SUMMARY: In this review, we provided a brief overview of the application of thermal ablation in peripheral lung tumors. We summarized the patient selection of thermal ablation. We highlighted the potential of thermal ablation to augment the antitumor immune response, offering a promising avenue for combined therapies. We summarized studies assessing the synergistic effects of thermal ablation and immunotherapy in preclinical and clinical settings. Lastly, we underscored the urgent issues that warrant in-depth exploration when applying thermal ablation and immunotherapy to lung tumor patients. KEY MESSAGES: This review emphasized the prospects of using thermal ablation combined with immunotherapy in patients with peripheral lung tumors. However, further research is needed to enhance and optimize this treatment strategy.


Assuntos
Imunoterapia , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/imunologia , Imunoterapia/métodos , Terapia Combinada , Técnicas de Ablação/métodos
3.
Phys Rev Lett ; 127(8): 086804, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34477422

RESUMO

Recently, two-dimensional superconductivity was discovered at the oxide interface between KTaO_{3} and LaAlO_{3} (or EuO), whose superconducting transition temperature T_{c} is up to 2.2 K and exhibits strong crystalline-orientation dependence. However, the origin of the interfacial electron gas, which becomes superconducting at low temperatures, remains elusive. Taking the LaAlO_{3}/KTaO_{3}(111) interface as an example, we have demonstrated that there exists a critical LaAlO_{3} thickness of ∼3 nm. Namely, a thinner LaAlO_{3} film will give rise to an insulating but not conducting (or superconducting) interface. By in situ transport measurements during growth, we have also revealed that the critical thickness can be suppressed if exposure to oxygen is avoided. These observations, together with other control experiments, suggest strongly that the origination of the electron gas is dominated by the electron transfer that is from oxygen vacancies in the LaAlO_{3} film to the KTaO_{3} substrate.

4.
Phys Rev Lett ; 126(2): 026802, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33512194

RESUMO

We report on the observation of a T_{c}∼0.9 K superconductivity at the interface between LaAlO_{3} film and the 5d transition metal oxide KTaO_{3}(110) single crystal. The interface shows a large anisotropy of the upper critical field, and its superconducting transition is consistent with a Berezinskii-Kosterlitz-Thouless transition. Both facts suggest that the superconductivity is two-dimensional (2D) in nature. The carrier density measured at 5 K is ∼7×10^{13} cm^{-2}. The superconducting layer thickness and coherence length are estimated to be ∼8 and ∼30 nm, respectively. Our result provides a new platform for the study of 2D superconductivity at oxide interfaces.

5.
Antioxidants (Basel) ; 12(9)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37760004

RESUMO

Geranylgeranylacetone (GGA) exerts cytoprotective activity against various toxic stressors via the thioredoxin (TRX) redox system; however, its effect on skin inflammation and molecular mechanism on inducing the TRX of GGA is still unknown. We investigated the effects of GGA in a murine irritant contact dermatitis (ICD) model induced by croton oil. Both a topical application and oral administration of GGA induced TRX production and Nrf2 activation. GGA ameliorated ear swelling, neutrophil infiltration, and inhibited the expression of TNF-α, IL-1ß, GM-CSF, and 8-OHdG. GGA's cytoprotective effect was stronger orally than topically in mice. In vitro studies also showed that GGA suppressed the expression of NLRP3, TNF-α, IL-1ß, and GM-CSF and scavenged ROS in PAM212 cells after phorbol myristate acetate stimulation. Moreover, GGA induced endogenous TRX production and Nrf2 nuclear translocation in PAM212 cells (dependent on the presence of ROS) and activated the PI3K-Akt signaling pathway. GGA significantly downregulated thioredoxin-interacting protein (TXNIP) levels in PAM212 cells treated with or without Nrf2 siRNA. After knocking down Nrf2 in PAM212 cells, the effect of GGA on TRX induction was significantly inhibited. This suggests that GGA suppress ICD by inducing endogenous TRX, which may be regulated by PI3K/Akt/Nrf2 mediation of the TRX redox system.

6.
Sci Adv ; 8(22): eabn4273, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35658041

RESUMO

The recent discovery of superconductivity at the interfaces between KTaO3 and EuO (or LaAlO3) gives birth to the second generation of oxide interface superconductors. This superconductivity exhibits a strong dependence on the surface plane of KTaO3, in contrast to the seminal LaAlO3/SrTiO3 interface, and the superconducting transition temperature Tc is enhanced by one order of magnitude. For understanding its nature, a crucial issue arises: Is the formation of oxide interfaces indispensable for the occurrence of superconductivity? Exploiting ionic liquid (IL) gating, we are successful in achieving superconductivity at KTaO3(111) and KTaO3(110) surfaces with Tc up to 2.0 and 1.0 K, respectively. This oxide-IL interface superconductivity provides a clear evidence that the essential physics of KTaO3 interface superconductivity lies in the KTaO3 surfaces doped with electrons. Moreover, the controllability with IL technique paves the way for studying the intrinsic superconductivity in KTaO3.

7.
J Phys Condens Matter ; 33(15)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33498026

RESUMO

We report growth, electronic structure and superconductivity of ultrathin epitaxial CoSi2films on Si (111). At low coverages, preferred islands with 2, 5 and 6 monolayers height develop, which agrees well with the surface energy calculation. We observe clear quantum well states as a result of electronic confinement and their dispersion agrees well with density functional theory calculations, indicating weak correlation effect despite strong contributions from Co 3delectrons.Ex situtransport measurements show that superconductivity persists down to at least 10 monolayers, with reducedTcbut largely enhanced upper critical field. Our study opens up the opportunity to study the interplay between quantum confinement, interfacial symmetry breaking and superconductivity in an epitaxial silicide film, which is technologically relevant in microelectronics.

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