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1.
Wei Sheng Yan Jiu ; 53(4): 532-560, 2024 Jul.
Artículo en Chino | MEDLINE | ID: mdl-39155219

RESUMEN

OBJECTIVE: To describe and analysis the detection rate of high normal blood pressure and high blood pressure among Chinese children and adolescents aged 7-17 years from 2016 to 2017 according to the clinical practice guideline for screening and management of high blood pressure in Children and Adolescents published by the American Academy of Pediatrics(the AAP reference), the international blood pressure references among Children and Adolescents aged 6 to 17 years(the international reference), health industry standard of the People's Republic of China "Reference of screening for elevated blood pressure among children and adolescents aged 7 to 18 years(WS/T 610-2018)"(the industry reference) and updating blood pressure references for Chinese children aged 3 to 17 years(the guideline reference). METHODS: Data was from the China Nutrition and Health Surveillance of Children and Lactating Women(2016-2017), in which the multistage stratified whole group random sampling method was used to draw participants from 275 surveillance sites in 31 provinces(autonomous regions and municipalities). In total, 67 231 participants were included according to the inclusion and exclusion criteria. Blood pressure was measured three times by trained staff using a validated oscillometric blood pressure monitor at the same point. The average blood pressure was calculated for the three measurements for SBP and DBP. To match the sampling design methodology, all values were weighted to represent the total population of Chinese children and adolescents 7-17 years of age considering sampling weights for each stratification based on the sixth population census data provided by the National Bureau of Statistics. RESULTS: The detection rate varied greatly under different references. The detection rate of high normal blood pressure was ranked from high to low according to the AAP reference(20.15%) > the guideline reference(17.29%) > the industry reference(13.14%) > the international reference(12.66%); the detection rate of high blood pressure in descending order is the guideline reference(24.31%) > the international reference(21.34%) > the AAP reference(20.59%) > the industry reference(19.96%). CONCLUSION: Although the consistency between the AAP references and international references and our national two references were medium to high, the difference in detection rate obtained by analysis was large. Considering the differences of demographic characteristics in the reference population, caution should be taken when applying foreign references to judge the blood pressure status of children and adolescents in China.


Asunto(s)
Presión Sanguínea , Hipertensión , Humanos , Adolescente , Niño , China , Femenino , Masculino , Hipertensión/diagnóstico , Valores de Referencia , Determinación de la Presión Sanguínea/métodos , Pueblos del Este de Asia
2.
Adv Sci (Weinh) ; : e2402819, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958507

RESUMEN

2D van der Waals (vdW) magnets have recently emerged as a promising material system for spintronic device innovations due to their intriguing phenomena in the reduced dimension and simple integration of magnetic heterostructures without the restriction of lattice matching. However, it is still challenging to realize Curie temperature far above room temperature and controllable magnetic anisotropy for spintronics application in 2D vdW magnetic materials. In this work, the pressure-tuned dome-like ferromagnetic-paramagnetic phase diagram in an iron-based 2D layered ferromagnet Fe3GaTe2 is reported. Continuously tunable magnetic anisotropy from out-of-plane to in-plane direction is achieved via the application of pressure. Such behavior is attributed to the competition between intralayer and interlayer exchange interactions and enhanced DOS near the Fermi level. The study presents the prominent properties of pressure-engineered 2D ferromagnetic materials, which can be used in the next-generation spintronic devices.

3.
Nat Nanotechnol ; 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039120

RESUMEN

In the presence of a high magnetic field, quantum Hall systems usually host both even- and odd-integer quantized states because of lifted band degeneracies. Selective control of these quantized states is challenging but essential to understand the exotic ground states and manipulate the spin textures. Here we demonstrate the quantum Hall effect in Bi2O2Se thin films. In magnetic fields as high as 50 T, we observe only even-integer quantum Hall states, but there is no sign of odd-integer states. However, when reducing the thickness of the epitaxial Bi2O2Se film to one unit cell, we observe both odd- and even-integer states in this Janus (asymmetric) film grown on SrTiO3. By means of a Rashba bilayer model based on the ab initio band structures of Bi2O2Se thin films, we can ascribe the only even-integer states in thicker films to the hidden Rasbha effect, where the local inversion-symmetry breaking in two sectors of the [Bi2O2]2+ layer yields opposite Rashba spin polarizations, which compensate with each other. In the one-unit-cell Bi2O2Se film grown on SrTiO3, the asymmetry introduced by the top surface and bottom interface induces a net polar field. The resulting global Rashba effect lifts the band degeneracies present in the symmetric case of thicker films.

4.
J Int Med Res ; 52(7): 3000605241259655, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39068529

RESUMEN

OBJECTIVE: This study aimed to identify significantly differentially expressed genes (DEGs) related to cervical cancer by exploring extensive gene expression datasets to unveil new therapeutic targets. METHODS: Gene expression profiles were extracted from the Gene Expression Omnibus, The Cancer Genome Atlas, and the Genotype-Tissue Expression platforms. A differential expression analysis identified DEGs in cervical cancer cases. Weighted gene co-expression network analysis (WGCNA) was implemented to locate genes closely linked to the clinical traits of diseases. Machine learning algorithms, including LASSO regression and the random forest algorithm, were applied to pinpoint key genes. RESULTS: The investigation successfully isolated DEGs pertinent to cervical cancer. Interleukin-24 was recognized as a pivotal gene via WGCNA and machine learning techniques. Experimental validations demonstrated that human interleukin (hIL)-24 inhibited proliferation, migration, and invasion, while promoting apoptosis, in SiHa and HeLa cervical cancer cells, affirming its role as a therapeutic target. CONCLUSION: The multi-database analysis strategy employed herein emphasized hIL-24 as a principal gene in cervical cancer pathogenesis. The findings suggest hIL-24 as a promising candidate for targeted therapy, offering a potential avenue for innovative treatment modalities. This study enhances the understanding of molecular mechanisms of cervical cancer and aids in the pursuit of novel oncological therapies.


Asunto(s)
Apoptosis , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Interleucinas , Invasividad Neoplásica , Neoplasias del Cuello Uterino , Humanos , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/metabolismo , Femenino , Proliferación Celular/genética , Movimiento Celular/genética , Interleucinas/genética , Interleucinas/metabolismo , Apoptosis/genética , Redes Reguladoras de Genes , Perfilación de la Expresión Génica , Células HeLa , Aprendizaje Automático , Línea Celular Tumoral
5.
Adv Mater ; 36(33): e2314190, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38885314

RESUMEN

Ferromagnetic Josephson junctions play a key role in understanding the interplay between superconductivity and ferromagnetism in condensed matter physics. The magnetic domain structures of the ferromagnet in such junctions can significantly affect the tunneling of the superconducting Cooper pairs due to the strong interactions between Cooper pairs and local magnetic moments in the ferromagnetic tunnel barrier. However, the underlying microscopic mechanism of relevant quasiparticle tunneling processes with magnetic domain structures remains largely unexplored. Here, the manipulation of Cooper-pair tunneling in the NbSe2/Cr2Ge2Te6/NbSe2 ferromagnetic Josephson junction is demonstrated by using a multidomain ferromagnetic barrier with anisotropic magnetic moments. The evolution of up-, down-magnetized domain and Bloch domain structures in Cr2Ge2Te6 barrier under external magnetic fields leads to the enhancement of the critical tunneling supercurrent and an unconventional dual-peak feature with two local maxima in the field-dependent critical current curve. The phenomenon of magnetic-field-modulated critical tunneling supercurrent can be well explained by the competition between the coherence length of tunneling Cooper pairs and the size of magnetic domain walls in Cr2Ge2Te6 barrier. This kind of ferromagnetic Josephson junction provides an intriguing material system for manipulating Cooper-pair tunneling by tuning the local magnetic moments within magnetic Josephson junction devices.

6.
Front Plant Sci ; 15: 1412175, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38779074

RESUMEN

Background: Populus simonii, a notable native tree species in northern China, demonstrates impressive resistance to stress, broad adaptability, and exceptional hybridization potential. DOF family is a class of specific transcription factors that only exist in plants, widely participating in plant growth and development, and also playing an important role in abiotic stress response. To date, there have been no reported studies on the DOF gene family in P. simonii, and the expression levels of this gene family in different tissues of poplar, as well as its expression patterns under cold, heat, and other stress conditions, remain unclear. Methods: In this study, DOF gene family were identified from the P. simonii genome, and various bioinformatics data on the DOF gene family, gene structure, gene distribution, promoters and regulatory networks were analyzed. Quantitative real time PCR technology was used to verify the expression patterns of the DOF gene family in different poplar tissues. Results: This research initially pinpointed 41 PSDOF genes in P. simonii genome. The chromosomal localization results revealed that the PSDOF genes is unevenly distributed among 19 chromosomes, with the highest number of genes located on chromosomes 4, 5, and 11. A phylogenetic tree was constructed based on the homology between Arabidopsis thaliana and P. simonii, dividing the 41 PSDOF genes into seven subgroups. The expression patterns of PSDOF genes indicated that specific genes are consistently upregulated in various tissues and under different stress conditions, suggesting their pivotal involvement in both plant development and response to stress. Notably, PSDOF35 and PSDOF28 serve as pivotal hubs in the interaction network, playing a unique role in coordinating with other genes within the family. Conclusion: The analysis enhances our comprehension of the functions of the DOF gene family in tissue development and stress responses within P. simonii. These findings provide a foundation for future exploration into the biological roles of DOF gene family.

7.
Gene ; 920: 148528, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-38703871

RESUMEN

BACKGROUND: The complex relationship between atrial fibrillation (AF) and type 2 diabetes mellitus (T2DM) suggests a potential role for epicardial adipose tissue (EAT) that requires further investigation. This study employs bioinformatics and experimental approaches to clarify EAT's role in linking T2DM and AF, aiming to unravel the biological mechanisms involved. METHOD: Bioinformatics analysis initially identified common differentially expressed genes (DEGs) in EAT from T2DM and AF datasets. Pathway enrichment and network analyses were then performed to determine the biological significance and network connections of these DEGs. Hub genes were identified through six CytoHubba algorithms and subsequently validated biologically, with further in-depth analyses confirming their roles and interactions. Experimentally, db/db mice were utilized to establish a T2DM model. AF induction was executed via programmed transesophageal electrical stimulation and burst pacing, focusing on comparing the incidence and duration of AF. Frozen sections and Hematoxylin and Eosin (H&E) staining illuminated the structures of the heart and EAT. Moreover, quantitative PCR (qPCR) measured the expression of hub genes. RESULTS: The study identified 106 DEGs in EAT from T2DM and AF datasets, underscoring significant pathways in energy metabolism and immune regulation. Three hub genes, CEBPZ, PAK1IP1, and BCCIP, emerged as pivotal in this context. In db/db mice, a marked predisposition towards AF induction and extended duration was observed, with HE staining verifying the presence of EAT. Additionally, qPCR validated significant changes in hub genes expression in db/db mice EAT. In-depth analysis identified 299 miRNAs and 33 TFs as potential regulators, notably GRHL1 and MYC. GeneMANIA analysis highlighted the hub genes' critical roles in stress responses and leukocyte differentiation, while immune profile correlations highlighted their impact on mast cells and neutrophils, emphasizing the genes' significant influence on immune regulation within the context of T2DM and AF. CONCLUSION: This investigation reveals the molecular links between T2DM and AF with a focus on EAT. Targeting these pathways, especially EAT-related ones, may enable personalized treatments and improved outcomes.


Asunto(s)
Fibrilación Atrial , Diabetes Mellitus Tipo 2 , Tejido Adiposo Epicárdico , Perfilación de la Expresión Génica , Pericardio , Animales , Humanos , Masculino , Ratones , Fibrilación Atrial/genética , Biología Computacional/métodos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Tejido Adiposo Epicárdico/metabolismo , Perfilación de la Expresión Génica/métodos , Redes Reguladoras de Genes , Ratones Endogámicos C57BL , Pericardio/metabolismo , Pericardio/patología , Transcriptoma
8.
Nat Nanotechnol ; 19(7): 932-940, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38750167

RESUMEN

Exploration of new dielectrics with a large capacitive coupling is an essential topic in modern electronics when conventional dielectrics suffer from the leakage issue near the breakdown limit. Here, to address this looming challenge, we demonstrate that rare-earth metal fluorides with extremely low ion migration barriers can generally exhibit an excellent capacitive coupling over 20 µF cm-2 (with an equivalent oxide thickness of ~0.15 nm and a large effective dielectric constant near 30) and great compatibility with scalable device manufacturing processes. Such a static dielectric capability of superionic fluorides is exemplified by MoS2 transistors exhibiting high on/off current ratios over 108, ultralow subthreshold swing of 65 mV dec-1 and ultralow leakage current density of ~10-6 A cm-2. Therefore, the fluoride-gated logic inverters can achieve notably higher static voltage gain values (surpassing ~167) compared with a conventional dielectric. Furthermore, the application of fluoride gating enables the demonstration of NAND, NOR, AND and OR logic circuits with low static energy consumption. In particular, the superconductor-insulator transition at the clean-limit Bi2Sr2CaCu2O8+δ can also be realized through fluoride gating. Our findings highlight fluoride dielectrics as a pioneering platform for advanced electronic applications and for tailoring emergent electronic states in condensed matter.

10.
Mol Biol Rep ; 51(1): 506, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622341

RESUMEN

BACKGROUND: Atrial Fibrillation (AF), a prevalent arrhythmic condition, is intricately associated with atrial fibrosis, a major pathological contributor. Central to the development of atrial fibrosis is myocardial inflammation. This study focuses on Atrial Natriuretic Peptide (ANP) and its role in mitigating atrial fibrosis, aiming to elucidate the specific mechanisms by which ANP exerts its effects, with an emphasis on fibroblast dynamics. METHODS AND RESULTS: The study involved forty Sprague-Dawley rats, divided into four groups: control, Angiotensin II (Ang II), Ang II + ANP, and ANP only. The administration of 1 µg/kg/min Ang II was given to Ang II and Ang II + ANP groups, while both Ang II + ANP and ANP groups received 0.1 µg/kg/min ANP intravenously for a duration of 14 days. Cardiac fibroblasts were used for in vitro validation of the proposed mechanisms. The study observed that rats in the Ang II and Ang II + ANP groups showed an increase in blood pressure and a decrease in body weight, more pronounced in the Ang II group. Diastolic dysfunction, a characteristic of the Ang II group, was alleviated by ANP. Additionally, ANP significantly reduced Ang II-induced atrial fibrosis, myofibroblast proliferation, collagen overexpression, macrophage infiltration, and the elevated expression of Interleukin 6 (IL-6) and Tenascin-C (TN-C). Transcriptomic sequencing indicated enhanced PI3K/Akt signaling in the Ang II group. Furthermore, in vitro studies showed that ANP, along with the PI3K inhibitor LY294002, effectively reduced PI3K/Akt pathway activation and the expression of TN-C, collagen-I, and collagen-III, which were induced by Ang II. CONCLUSIONS: The study demonstrates ANP's potential in inhibiting myocardial inflammation and reducing atrial fibrosis. Notably, ANP's effect in countering atrial fibrosis seems to be mediated through the suppression of the Ang II-induced PI3K/Akt-Tenascin-C signaling pathway. These insights enhance our understanding of AF pathogenesis and position ANP as a potential therapeutic agent for treating atrial fibrosis.


Asunto(s)
Fibrilación Atrial , Factor Natriurético Atrial , Ratas , Animales , Ratas Sprague-Dawley , Factor Natriurético Atrial/farmacología , Factor Natriurético Atrial/metabolismo , Proteínas Proto-Oncogénicas c-akt , Fosfatidilinositol 3-Quinasas , Tenascina , Fibrilación Atrial/tratamiento farmacológico , Angiotensina II/farmacología , Inflamación/tratamiento farmacológico , Colágeno , Fibrosis
11.
Nano Lett ; 24(18): 5562-5569, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38682815

RESUMEN

Transition metal trichalcogenides (TMTCs) offer remarkable opportunities for tuning electronic states through modifications in chemical composition, temperature, and pressure. Despite considerable interest in TMTCs, there remain significant knowledge gaps concerning the evolution of their electronic properties under compression. In this study, we employ experimental and theoretical approaches to comprehensively explore the high-pressure behavior of the electronic properties of TiS3, a quasi-one-dimensional (Q1D) semiconductor, across various temperature ranges. Through high-pressure electrical resistance and magnetic measurements at elevated pressures, we uncover a distinctive sequence of phase transitions within TiS3, encompassing a transformation from an insulating state at ambient pressure to the emergence of an incipient superconducting state above 70 GPa. Our findings provide compelling evidence that superconductivity at low temperatures of ∼2.9 K is a fundamental characteristic of TiS3, shedding new light on the intriguing high-pressure electronic properties of TiS3 and underscoring the broader implications of our discoveries for TMTCs in general.

12.
ACS Appl Mater Interfaces ; 16(11): 13980-13988, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38446715

RESUMEN

The anisotropic thermal transport properties of low-symmetry two-dimensional materials play an important role in understanding heat dissipation and optimizing thermal management in integrated devices. Examples of efficient energy dissipation and enhanced power sustainability have been demonstrated in nanodevices based on materials with anisotropic thermal transport properties. However, the exploration of materials with high thermal conductivity and strong in-plane anisotropy remains challenging. Herein, we demonstrate the observation of anisotropic in-plane thermal conductivities of few-layer SiP2 based on the micro-Raman thermometry method. For suspended SiP2 nanoflake, the thermal conductivity parallel to P-P chain direction (κ∥b) can reach 131 W m-1 K-1 and perpendicular to P-P chain direction (κ⊥b) is 89 W m-1 K-1 at room temperature, resulting in a significant anisotropic ratio (κ∥b/κ⊥b) of 1.47. Note that such a large anisotropic ratio mainly results from the higher phonon group velocity along the P-P chain direction. We also found that the thermal conductivity can be effectively modulated by increasing the SiP2 thickness, reaching a value as high as 202 W m-1 K-1 (120 W m-1 K-1) for κ∥b (κ⊥b) at 111 nm thickness, which is the highest among layered anisotropic phosphide materials. Notably, the anisotropic ratio always remains at a high level between 1.47 and 1.68, regardless of the variation of SiP2 thickness. Our observation provides a new platform to verify the fundamental theory of thermal transport and a crucial guidance for designing efficient thermal management schemes of anisotropic electronic devices.

13.
Nano Lett ; 23(22): 10282-10289, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37906179

RESUMEN

Quasiparticles consisting of correlated electron(s) and hole(s), such as excitons and trions, play important roles in the optical phenomena of van der Waals semiconductors and serve as unique platforms for studies of many-body physics. Herein, we report a gate-tunable exciton-to-trion transition in pressurized monolayer MoSe2, in which the electronic band structures are modulated continuously within a diamond anvil cell. The emission energies of both the exciton and trion undergo large blueshifts over 90 meV with increasing pressure. Surprisingly, the trion binding energy remains constant at 30 meV, regardless of the applied pressure. Combining ab initio density functional theory calculations and quantum Monte Carlo simulations, we find that the remarkable robustness of the trion binding energy originates from the spatially diffused nature of the trion wave function and the weak correlation between its constituent electron-hole pairs. Our findings shed light on the optical properties of correlated excitonic quasiparticles in low-dimensional materials.

14.
Front Immunol ; 14: 1213008, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37868980

RESUMEN

Rationale and introduction: It is of significance to assess the severity and predict the mortality of patients with connective tissue disease-associated interstitial lung disease (CTD-ILD). In this double-center retrospective study, we developed and validated a radiomics nomogram for clinical management by using the ILD-GAP (gender, age, and pulmonary physiology) index system. Materials and methods: Patients with CTD-ILD were staged using the ILD-GAP index system. A clinical factor model was built by demographics and CT features, and a radiomics signature was developed using radiomics features extracted from CT images. Combined with the radiomics signature and independent clinical factors, a radiomics nomogram was constructed and evaluated by the area under the curve (AUC) from receiver operating characteristic (ROC) analyses. The models were externally validated in dataset 2 to evaluate the model generalization ability using ROC analysis. Results: A total of 245 patients from two clinical centers (dataset 1, n = 202; dataset 2, n = 43) were screened. Pack-years of smoking, traction bronchiectasis, and nine radiomics features were used to build the radiomics nomogram, which showed favorable calibration and discrimination in the training cohort {AUC, 0.887 [95% confidence interval (CI): 0.827-0.940]}, the internal validation cohort [AUC, 0.885 (95% CI: 0.816-0.922)], and the external validation cohort [AUC, 0.85 (95% CI: 0.720-0.919)]. Decision curve analysis demonstrated that the nomogram outperformed the clinical factor model and radiomics signature in terms of clinical usefulness. Conclusion: The CT-based radiomics nomogram showed favorable efficacy in predicting individual ILD-GAP stages.


Asunto(s)
Enfermedades del Tejido Conjuntivo , Enfermedades Pulmonares Intersticiales , Humanos , Estudios Retrospectivos , Enfermedades Pulmonares Intersticiales/diagnóstico por imagen , Enfermedades Pulmonares Intersticiales/etiología , Enfermedades del Tejido Conjuntivo/complicaciones , Enfermedades del Tejido Conjuntivo/diagnóstico por imagen , Área Bajo la Curva , Tomografía Computarizada por Rayos X
15.
Plants (Basel) ; 12(20)2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37896029

RESUMEN

The auxin/indole-3-acetic acid (Aux/IAA) and auxin response factor (ARF) genes are two crucial gene families in the plant auxin signaling pathway. Nonetheless, there is limited knowledge regarding the Aux/IAA and ARF gene families in Populus simonii. In this study, we first identified 33 putative PsIAAs and 35 PsARFs in the Populus simonii genome. Analysis of chromosomal location showed that the PsIAAs and PsARFs were distributed unevenly across 17 chromosomes, with the greatest abundance observed on chromosomes 2. Furthermore, based on the homology of PsIAAs and PsARFs, two phylogenetic trees were constructed, classifying 33 PsIAAs and 35 PsARFs into three subgroups each. Five pairs of PsIAA genes were identified as the outcome of tandem duplication, but no tandem repeat gene pairs were found in the PsARF family. The expression profiling of PsIAAs and PsARFs revealed that several genes exhibited upregulation in different tissues and under various stress conditions, indicating their potential key roles in plant development and stress responses. The variance in expression patterns of specific PsIAAs and PsARFs was corroborated through RT-qPCR analysis. Most importantly, we instituted that the PsIAA7 gene, functioning as a central hub, exhibits interactions with numerous Aux/IAA and ARF proteins. Furthermore, subcellular localization findings indicate that PsIAA7 functions as a protein localized within the nucleus. To conclude, the in-depth analysis provided in this study will contribute significantly to advancing our knowledge of the roles played by PsIAA and PsARF families in both the development of P. simonii tissue and its responses to stress. The insights gained will serve as a valuable asset for further inquiries into the biological functions of these gene families.

16.
Sci Adv ; 9(36): eadf6758, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37683003

RESUMEN

Two-dimensional superconductivity is primarily realized in atomically thin layers through extreme exfoliation, epitaxial growth, or interfacial gating. Apart from their technical challenges, these approaches lack sufficient control over the Fermiology of superconducting systems. Here, we offer a Fermiology-engineering approach, allowing us to desirably tune the coherence length of Cooper pairs and the dimensionality of superconducting states in arsenic phosphides AsxP1-x under hydrostatic pressure. We demonstrate how this turns these compounds into tunable two-dimensional superconductors with a dome-shaped phase diagram even in the bulk limit. This peculiar behavior is shown to result from an unconventional valley-dimensionality locking mechanism, driven by a delicate competition between three-dimensional hole-type and two-dimensional electron-type energy pockets spatially separated in momentum space. The resulting dimensionality crossover is further discussed to be systematically controllable by pressure and stoichiometry tuning. Our findings pave a unique way to realize and control superconducting phases with special pairing and dimensional orders.

17.
Nat Commun ; 14(1): 5568, 2023 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-37689758

RESUMEN

Van der Waals dielectrics are fundamental materials for condensed matter physics and advanced electronic applications. Most dielectrics host isotropic structures in crystalline or amorphous forms, and only a few studies have considered the role of anisotropic crystal symmetry in dielectrics as a delicate way to tune electronic properties of channel materials. Here, we demonstrate a layered anisotropic dielectric, SiP2, with non-symmorphic twofold-rotational C2 symmetry as a gate medium which can break the original threefold-rotational C3 symmetry of MoS2 to achieve unexpected linearly-polarized photoluminescence and anisotropic second harmonic generation at SiP2/MoS2 interfaces. In contrast to the isotropic behavior of pristine MoS2, a large conductance anisotropy with an anisotropy index up to 1000 can be achieved and modulated in SiP2-gated MoS2 transistors. Theoretical calculations reveal that the anisotropic moiré potential at such interfaces is responsible for the giant anisotropic conductance and optical response. Our results provide a strategy for generating exotic functionalities at dielectric/semiconductor interfaces via symmetry engineering.

18.
Mol Biol Rep ; 50(12): 9757-9767, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37676431

RESUMEN

BACKGROUND: Artial fibrosis has been recognized as a typical pathological change in atrial fibrillation. Although present evidence suggests that microRNA-499-5p (miR-499-5p) plays an important role in the development of atrial fibrosis, the specific mechanism is not fully understood. Therefore, this study attempted to assess the influence of miR-499-5p on atrial fibroblasts and explore the potential molecular mechanism. METHODS: Atrial fibroblasts from sprague dawley rat were respectively transfected with miR-499-5p mimic, miR-499-5p negative control and miR-499-5p inhibitor, atrial fibroblasts without any treatment were also established. Cell counting kit-8 assay and transwell assay were used to detect the proliferation and migration of atrial fibroblasts in each group. Expressions of miR-499-5p, TGF-ß1, smad2, α-SMA, collagen-I and TGFß-R1 in mRNA and protein level were subsequently detected via quantitative real-time polymerase chain reaction and western blot. Furthermore, the prediction of the binding sites of miR-499-5p and TGFß-R1 was performed via the bioinformatics online software TargetScan and verified by dual luciferase reporter. RESULTS: By utilizing miR-499-5p-transfected atrial fibroblasts model, expression of miR-499-5p in the miR-499-5p mimic group was upregulated, while it was downregulated in the miR-499-5p inhibitors group. Upregulated miR-499-5p expression led to to a significant decrease in the proliferative and migratory ability of cultured atrial fibroblasts, while downregulated miR-499-5p expression led to a significant increase in the proliferative and migratory ability of cultured atrial fibroblasts. Additionally, upregulated miR-499-5p expression made a significant rise in TGF-ß1-induced mRNA and protein expression of TGF-ß1, TGFß-R1, smad2, α-SMA and collagen-I in atrial fibroblasts. Furthermore, results from the dual luciferase reporter conformed that miR-499-5p may repress TGFß-R1 by binding the 3'UTR of TGFß-R1 directly. CONCLUSIONS: miR-499-5p is able to inhibit the activation of transforming growth factor ß-induced Smad2 signaling and eventually suppressed the proliferation, migration and invasion of atrial fibroblasts and collagen synthesis by targeting TGFß-R1.


Asunto(s)
Fibrilación Atrial , MicroARNs , Receptores de Factores de Crecimiento Transformadores beta , Animales , Ratas , Fibrilación Atrial/genética , Fibrilación Atrial/patología , Proliferación Celular/genética , Colágeno Tipo I/metabolismo , Fibroblastos/metabolismo , Fibrosis , Luciferasas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Ratas Sprague-Dawley , ARN Mensajero/genética , Transducción de Señal/genética , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Proteína Smad2/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/genética , Receptores de Factores de Crecimiento Transformadores beta/metabolismo
19.
Nat Nanotechnol ; 18(8): 867-874, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37322146

RESUMEN

The Berry curvature dipole (BCD) is a key parameter that describes the geometric nature of energy bands in solids. It defines the dipole-like distribution of Berry curvature in the band structure and plays a key role in emergent nonlinear phenomena. The theoretical rationale is that the BCD can be generated at certain symmetry-mismatched van der Waals heterointerfaces even though each material has no BCD in its band structure. However, experimental confirmation of such a BCD induced via breaking of the interfacial symmetry remains elusive. Here we demonstrate a universal strategy for BCD generation and observe BCD-induced gate-tunable spin-polarized photocurrent at WSe2/SiP interfaces. Although the rotational symmetry of each material prohibits the generation of spin photocurrent under normal incidence of light, we surprisingly observe a direction-selective spin photocurrent at the WSe2/SiP heterointerface with a twist angle of 0°, whose amplitude is electrically tunable with the BCD magnitude. Our results highlight a BCD-spin-valley correlation and provide a universal approach for engineering the geometric features of twisted heterointerfaces.

20.
Sci Bull (Beijing) ; 68(10): 990-997, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37100643

RESUMEN

The itinerant ferromagnetism can be induced by a van Hove singularity (VHS) with a divergent density of states at Fermi level. Utilizing the giant magnified dielectric constant εr of SrTiO3(111) substrate with cooling, here we successfully manipulated the VHS in the epitaxial monolayer (ML) 1T-VSe2 film approaching to Fermi level via the large interfacial charge transfer, and thus induced a two-dimensional (2D) itinerant ferromagnetic state below 3.3 K. Combining the direct characterization of the VHS structure via angle-resolved photoemission spectroscopy (ARPES), together with the theoretical analysis, we ascribe the manipulation of VHS to the physical origin of the itinerant ferromagnetic state in ML 1T-VSe2. Therefore, we further demonstrated that the ferromagnetic state in the 2D system can be controlled through manipulating the VHS by engineering the film thickness or replacing the substrate. Our findings clearly evidence that the VHS can serve as an effective manipulating degree of freedom for the itinerant ferromagnetic state, expanding the application potentials of 2D magnets for the next-generation information technology.


Asunto(s)
Asma , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Imanes , Frío
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