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1.
Nano Lett ; 24(17): 5125-5131, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38639405

RESUMO

We report a study of thickness-dependent interband and intraband magnetic breakdown by thermoelectric quantum oscillations in ZrSiSe nanoplates. Under high magnetic fields of up to 30 T, quantum oscillations arising from degenerated hole pockets were observed in thick ZrSiSe nanoplates. However, when decreasing the thickness, plentiful multifrequency quantum oscillations originating from hole and electron pockets are captured. These multiple frequencies can be explained by the emergent interband magnetic breakdown enclosing individual hole and electron pockets and intraband magnetic breakdown within spin-orbit coupling (SOC) induced saddle-shaped electron pockets, resulting in the enhanced contribution to thermal transport in thin ZrSiSe nanoplates. These experimental frequencies agree well with theoretical calculations of the intriguing tunneling processes. Our results introduce a new member of magnetic breakdown to the field and open up a dimension for modulating magnetic breakdown, which holds fundamental significance for both low-dimensional topological materials and the physics of magnetic breakdown.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38427757

RESUMO

BACKGROUND: The aim of this study was to explore new biomarkers of Kawasaki disease (KD) and provide evidence for clinical diagnosis and treatment. MATERIALS AND METHODS: Gene Expression Omnibus (GEO) datasets GSE68004 and GSE73461 were downloaded, and the differentially expressed genes (DGEs) were taken, along with DEGs enrichment analysis and protein interaction network. Finally, five algorithms in CytoHubba plug-in were applied to obtain hub genes. RESULTS: In this study, 32 Co-DEGs were identified, and these genes mainly participated in neutrophil degranulation, neutrophil activation involved in immune response, and negative regulation of cytokine production involved in immune response; meanwhile, they were primarily enriched in starch and sucrose metabolism, fatty acid metabolism, autophagy and apoptosis, ferroptosis, and other pathways. Combined with the results of PPI and CytoHubba, 13 key genes were selected as follows: S100A12, HK3, HP, MMP9, MCEMP1, PYGL, ARG1, HIST2H2AA, ANXA3, HIST2H2AC, HIST2H2AA3, GYG1, DYSF. CONCLUSIONS: These 13 key genes may mediate the occurrence and development of KD through various processes such as immune regulation, inflammatory response, glucose metabolism, autophagy, and apoptosis, which provide valuable references for the diagnosis and treatment of KD.

3.
Environ Pollut ; 344: 123404, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38244901

RESUMO

Antibiotics are causing widespread concern as one of the emerging contaminants. There is the abuse of antibiotics in high-density open aquaculture, and the tailwater is often discharged into surrounding rivers. At the same time, the water replenishment of open aquaculture ponds from nearby rivers containing antibiotic contamination from different sources may result in cross-contamination. However, it is still unclear which pollution intensity is greater in rivers or in open aquaculture. So in this paper, the levels of 20 antibiotics (i.e., Fluoroquinolones (FQs), Sulfonamides (SAs), Tetracyclines (TCs), Macrolides (MLs) and Lincosamides (LCs)) in rivers and high-density open aquaculture ponds were investigated in the Baini River basin in the suburbs of Guangzhou, China. The results showed that norfloxacin (NFX) was the predominant antibiotic in river and aquaculture water, with concentrations ranging from 6.12 to 156.04 ng/L and from 7.47 to 82.62 ng/L in both aquatic systems, respectively. As for the pollution intensity of antibiotics, the annual pollution contribution (28.64 kg/a) of the river water supply to open aquaculture is higher than that (10.81 kg/a) of open aquaculture to the river, which means river pollution has a greater impact on aquaculture ponds. The risk quotient (RQ) showed that the ecological risk of lincomycin (LIN), erythromycin (ERY), sulfamethoxazole (SMX), norfloxacin (NFX), ciprofloxacin (CFX) and chlortetracycline (CTC) in rivers and aquaculture environments had high ecological risks from 1.21 to 1.81. Water interactions with contaminated rivers will result in a corresponding increase in the ecological risk of antibiotics in the aquaculture environment. Overall, according to the results, the risk of polluted rivers to open aquaculture cannot be ignored, and it is recommended that open aquaculture should use these water sources with caution, and that the water quality evaluation of aquaculture water should be increased with monitoring indicators for emerging contaminants such as antibiotics.


Assuntos
Antibacterianos , Norfloxacino , Lagoas , Rios , Aquicultura
4.
Expert Rev Respir Med ; 17(9): 743-751, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37776047

RESUMO

INTRODUCTION: KRAS is the most frequently mutated oncogene in cancer and encodes a key signaling protein in tumors. Due to its high affinity for GTP and the lack of a large binding pocket that allosteric inhibitors can occupy, KRAS has long been considered 'non-druggable.' Finding effective treatment measures for patients with KRAS mutations is our top priority. AREAS COVERED: In this article, we will provide an overview of the KRAS pathway and review the current state of therapeutic strategies for targeting oncogenic KRAS, as well as their potential to improve outcomes in patients with KRAS-mutant malignancies. We will also discuss the development of these strategies and gave an outlook on prospects. EXPERT OPINION: KRAS mutations have posed a significant challenge in the treatment of advanced non-small cell lung cancer (NSCLC) over the past few decades. However, the emergence of immunotherapy and KRAS inhibitors, such as Sotorasib (AMG 510) and Adagrasib (MRTX849), has marked a new era in cancer therapy. As more research and clinical trials continue, we anticipate the development of more effective treatment strategies and better options for lung cancer patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Prognóstico , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação
5.
Nano Lett ; 23(19): 9026-9033, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37767914

RESUMO

The quantum Hall effect is one of the exclusive properties displayed by Dirac Fermions in topological insulators, which propagates along the chiral edge state and gives rise to quantized electron transport. However, the quantum Hall effect formed by the nondegenerate Dirac surface states has been elusive so far. Here, we demonstrate the nondegenerate integer quantum Hall effect from the topological surface states in three-dimensional (3D) topological insulator ß-Ag2Te nanostructures. Surface-state dominant conductance renders quantum Hall conductance plateaus with a step of e2/h, along with typical thermopower behaviors of two-dimensional (2D) massless Dirac electrons. The 2D nature of the topological surface states is proven by the electrical and thermal transport responses under tilted magnetic fields. Moreover, the degeneracy of the surface states is removed by structure inversion asymmetry (SIA). The evidenced SIA-induced nondegenerate integer quantum Hall effect in low-symmetry ß-Ag2Te has implications for both fundamental study and the realization of topological magneto-electric effects.

6.
J Environ Manage ; 324: 116311, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36162319

RESUMO

The recirculating aquaculture system (RAS) has attracted much attention in China as a way to rapidly transform and upgrade aquaculture ponds to realize zero-emissions of pollutants in aquaculture tail water. Tail water purification ponds (TWPPs) play an important role in the treatment of aquaculture wastewater. However, until now, there have been few reports on the occurrence of antibiotics in RAS and the removal of antibiotics from the TWPPs of RAS. Therefore, this study focused on the occurrence of antibiotics in a typical ecological RAS. For comparison, the same measurements were simultaneously carried out in nearby open aquaculture ponds and rivers. The pollution level and spatial distribution of antibiotics in the RAS and the removal of antibiotics in the TWPPs were explored. The results showed that (1) eleven and twelve antibiotics were detected in water and sediment samples in the RAS, respectively, but no antibiotics were found in fish muscles and feed. Erythromycin (ERY), lincomycin (LIN), and ciprofloxacin (CFX) were the three main types of antibiotics found in water and sediment samples. (2) The TWPPs of the RAS can effectively remove antibiotics in aquaculture water. The antibiotic concentration in recirculating aquaculture ponds of the RAS was as high as 180 ng/L. After treatments in the TWPPs, the antibiotic concentration of aquaculture water decreased to 81.6 ng/L (3) The antibiotic concentrations in recirculating aquaculture ponds (25.2-180 ng/L) were lower than those in the nearby open aquaculture ponds (126-267.3 ng/L), and the concentration of antibiotics in the sediments of recirculating aquaculture ponds was up to 22.9 ng/g, while that in TWPPs was as high as 56.1 ng/g. In conclusion, the antibiotic residues in the RAS were low after antibiotics were banned in feed in China, and the removal of antibiotics in the TWPPs was more pronounced. Furthermore, cross-contamination was found between the RAS, surrounding open aquaculture ponds and the river, and the water supply of the RAS was likely to be the main contributor of antibiotics in the aquaculture environments. This study can help the government formulate discharge standards for antibiotics in aquaculture and also provide a reference for the transformation and upgrading of aquaculture ponds to achieve a zero-emission aquaculture mode.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água , Animais , Antibacterianos/análise , Poluentes Químicos da Água/análise , Aquicultura , Lagoas , Água , China
7.
Adv Mater ; 34(24): e2200145, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35338784

RESUMO

The discovery of 2D van der Waals (vdW) magnetic materials is of great significance to explore intriguing 2D magnetic physics and develop innovative spintronic devices. In this work, a new quasi-1D vdW layered compound CrZr4 Te14 is successfully synthesized. Owing to the existence of 1D [CrTe2 ] and [ZrTe3 ] chains along the b-axis, CrZr4 Te14 crystals show strong anisotropy of phonon vibrations, electrical transport, and magnetism. Density functional theory calculations reveal the ferromagnetic (FM) coupling within the [CrTe2 ] chain, while the interchain and interlayer couplings are both weakly antiferromagnetic (AF). Notably, a large intrinsic negative magnetoresistance (nMR) of -56% is achieved at 2 K under 9 T, and the in-plane anisotropic factor of nMR can reach up to 8.2 in the CrZr4 Te14 device. The 1D FM chains and anisotropic nMR effect make CrZr4 Te14 an interesting platform for exploring novel polarization-sensitive spintronics.

8.
Nat Commun ; 12(1): 6580, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34772912

RESUMO

Superconductor-ferromagnet interfaces in two-dimensional heterostructures present a unique opportunity to study the interplay between superconductivity and ferromagnetism. The realization of such nanoscale heterostructures in van der Waals (vdW) crystals remains largely unexplored due to the challenge of making atomically-sharp interfaces from their layered structures. Here, we build a vdW ferromagnetic Josephson junction (JJ) by inserting a few-layer ferromagnetic insulator Cr2Ge2Te6 into two layers of superconductor NbSe2. The critical current and corresponding junction resistance exhibit a hysteretic and oscillatory behavior against in-plane magnetic fields, manifesting itself as a strong Josephson coupling state. Also, we observe a central minimum of critical current in some JJ devices as well as a nontrivial phase shift in SQUID structures, evidencing the coexistence of 0 and π phase in the junction region. Our study paves the way to exploring sensitive probes of weak magnetism and multifunctional building-blocks for phase-related superconducting circuits using vdW heterostructures.

9.
Nano Lett ; 21(1): 288-297, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33346673

RESUMO

The motion of Abrikosov vortices is the dominant origin of dissipation in type II superconductors subjected to a magnetic field, which leads to a finite electrical resistance. It is generally believed that the increase in the magnetic field results in the aggravation of energy dissipation through the increase in vortex density. Here, we show a distinctive re-entrance of the dissipationless state in quasi-one-dimensional superconducting Ta2PdS5 nanostrips. Utilizing magnetotransport measurements, we unveil a prominent magnetoresistance drop with the increase in the magnetic field below the superconducting transition temperature, manifesting itself as a giant re-entrance to the superconducting phase. Time-dependent Ginzburg-Landau calculations show that this is originated from the suppression of the vortex motion by the increased energy barrier on the edges. Interestingly, both our experiments and simulations demonstrate that this giant re-entrance of superconductivity occurs only in certain geometrical regimes because of the finite size of the vortex.

10.
Nat Commun ; 11(1): 5634, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33159059

RESUMO

The rise of two-dimensional (2D) crystalline superconductors has opened a new frontier of investigating unconventional quantum phenomena in low dimensions. However, despite the enormous advances achieved towards understanding the underlying physics, practical device applications like sensors and detectors using 2D superconductors are still lacking. Here, we demonstrate nonreciprocal antenna devices based on atomically thin NbSe2. Reversible nonreciprocal charge transport is unveiled in 2D NbSe2 through multi-reversal antisymmetric second harmonic magnetoresistance isotherms. Based on this nonreciprocity, our NbSe2 antenna devices exhibit a reversible nonreciprocal sensitivity to externally alternating current (AC) electromagnetic waves, which is attributed to the vortex flow in asymmetric pinning potentials driven by the AC driving force. More importantly, a successful control of the nonreciprocal sensitivity of the antenna devices has been achieved by applying electromagnetic waves with different frequencies and amplitudes. The device's response increases with increasing electromagnetic wave amplitude and exhibits prominent broadband sensing from 5 to 900 MHz.

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