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1.
Adv Mater ; : e2405009, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39104281

RESUMO

The development of superconducting materials has attracted significant attention not only for their improved performance, such as high transition temperature (TC), but also for the exploration of their underlying physical mechanisms. Recently, considerable efforts have been focused on interfaces of materials, a distinct category capable of inducing superconductivity at non-superconducting material interfaces or augmenting the TC at the interface between a superconducting material and a non-superconducting material. Here, two distinct types of interfaces along with their unique characteristics are reviewed: interfacial superconductivity and interface-enhanced superconductivity, with a focus on the crucial factors and potential mechanisms responsible for enhancing superconducting performance. A series of materials systems is discussed, encompassing both historical developments and recent progress from the perspectives of technical innovations and the exploration of new material classes. The overarching goal is to illuminate pathways toward achieving high TC, expanding the potential of superconducting parameters across interfaces, and propelling superconductivity research toward practical, high-temperature applications.

2.
Nat Commun ; 15(1): 6630, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103337

RESUMO

Unfavourable conditions, such as prolonged drought and high salinity, pose a threat to the survival and agricultural yield of plants. The phytohormone ABA plays a key role in the regulation of plant stress adaptation and is often maintained at high levels for extended periods. While much is known about ABA signal perception and activation in the early signalling stage, the molecular mechanism underlying desensitization of ABA signalling remains largely unknown. Here we demonstrate that in the endoplasmic reticulum (ER)-Golgi network, the key regulators of ABA signalling, SnRK2.2/2.3, undergo N-glycosylation, which promotes their redistribution from the nucleus to the peroxisomes in Arabidopsis roots and influences the transcriptional response in the nucleus during prolonged ABA signalling. On the peroxisomal membrane, SnRK2s can interact with glucose-6-phosphate (G6P)/phosphate translocator 1 (GPT1) to maintain NADPH homeostasis through increased activity of the peroxisomal oxidative pentose phosphate pathway (OPPP). The resulting maintenance of NADPH is essential for the modulation of hydrogen peroxide (H2O2) accumulation, thereby relieving ABA-induced root growth inhibition. The subcellular dynamics of SnRK2s, mediated by N-glycosylation suggest that ABA responses transition from transcriptional regulation in the nucleus to metabolic processes in the peroxisomes, aiding plants in adapting to long-term environmental stress.


Assuntos
Ácido Abscísico , Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , NADP , Peroxissomos , Proteínas Serina-Treonina Quinases , Transdução de Sinais , Arabidopsis/metabolismo , Arabidopsis/genética , Peroxissomos/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Glicosilação , Ácido Abscísico/metabolismo , NADP/metabolismo , Peróxido de Hidrogênio/metabolismo , Retículo Endoplasmático/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Núcleo Celular/metabolismo , Complexo de Golgi/metabolismo , Via de Pentose Fosfato , Reguladores de Crescimento de Plantas/metabolismo
3.
Cereb Cortex ; 34(8)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39123310

RESUMO

Structural covariance networks and causal effects within can provide critical information on gray matter reorganization and disease-related hierarchical changes. Based on the T1WI data of 43 classical trigeminal neuralgia patients and 45 controls, we constructed morphological similarity networks of cortical thickness, sulcal depth, fractal dimension, and gyrification index. Moreover, causal structural covariance network analyses were conducted in regions with morphological abnormalities or altered nodal properties, respectively. We found that patients showed reduced sulcal depth, gyrification index, and fractal dimension, especially in the salience network and the default mode network. Additionally, the integration of the fractal dimension and sulcal depth networks was significantly reduced, accompanied by decreased nodal efficiency of the bilateral temporal poles, and right pericalcarine cortex within the sulcal depth network. Negative causal effects existed from the left insula to the right caudal anterior cingulate cortex in the gyrification index map, also from bilateral temporal poles to right pericalcarine cortex within the sulcal depth network. Collectively, patients exhibited impaired integrity of the covariance networks in addition to the abnormal gray matter morphology in the salience network and default mode network. Furthermore, the patients may experience progressive impairment in the salience network and from the limbic system to the sensory system in network topology, respectively.


Assuntos
Córtex Cerebral , Imageamento por Ressonância Magnética , Neuralgia do Trigêmeo , Humanos , Neuralgia do Trigêmeo/patologia , Neuralgia do Trigêmeo/diagnóstico por imagem , Neuralgia do Trigêmeo/fisiopatologia , Feminino , Masculino , Pessoa de Meia-Idade , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Idoso , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/patologia , Adulto , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Mapeamento Encefálico
4.
Angew Chem Int Ed Engl ; : e202412350, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39152766

RESUMO

Zero-dimensional (0D) hybrid metal halides have been emerged as room-temperature phosphorescence (RTP) materials, but synchronous optimization of multiple phosphorescence performance in one structural platform remains less resolved, and stable RTP activity in aqueous medium is also unrealized due to serious instability toward water and oxygen. Herein, we demonstrated a photophysical tuning strategy in a new 0D hybrid zinc halide family of (BTPP)2ZnX4 (BTPP = benzyltriphenylphosphonium, X = Cl and Br). Infrequently, the delicate combination of organic and inorganic species enables this family to display multiple ultralong green afterglow and efficient self-trapped exciton (STE) associated cyan phosphorescence. Compared with inert luminescence of [BTPP]+ cation, incorporation of anionic [ZnX4]2- effectively enhance the spin-orbit coupling effect, which significantly boosts the photoluminescence quantum yield (PLQY) up to 30.66% and 54.62% for afterglow and phosphorescence, respectively. Synchronously, the corresponding luminescence lifetime extend to 143.94 ms and 0.308 µs surpassing the indiscernible phosphorescence of [BTPP]X salt. More importantly, this halide family presents robust RTP emission with nearly unattenuated PLQY in water and harsh condition (acid and basic aqueous solution) over half a year. The highly efficient integrated afterglow and STE phosphorescence as well as ultrahigh aqueous state RTP realize multiple anti-counterfeiting applications in wide chemical environments.

5.
Sensors (Basel) ; 24(15)2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39123914

RESUMO

Ethanol sensors have found extensive applications across various industries, including the chemical, environmental, transportation, and healthcare sectors. With increasing demands for enhanced performance and reduced energy consumption, there is a growing need for developing new ethanol sensors. Micro-electromechanical system (MEMS) devices offer promising prospects in gas sensor applications due to their compact size, low power requirements, and seamless integration capabilities. In this study, SnO2-TiO2 nanocomposites with varying molar ratios of SnO2 and TiO2 were synthesized via ball milling and then printed on MEMS chips for ethanol sensing using electrohydrodynamic (EHD) printing. The study indicates that the two metal oxides dispersed evenly, resulting in a well-formed gas-sensitive film. The SnO2-TiO2 composite exhibits the best performance at a molar ratio of 1:1, with a response value of 25.6 to 50 ppm ethanol at 288 °C. This value is 7.2 times and 1.8 times higher than that of single SnO2 and TiO2 gas sensors, respectively. The enhanced gas sensitivity can be attributed to the increased surface reactive oxygen species and optimized material resistance resulting from the chemical and electronic effects of the composite.

6.
Adv Mater ; : e2402053, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148282

RESUMO

Reducing non-radiative recombination and addressing band alignment mismatches at interfaces remain major challenges in achieving high-performance wide-bandgap perovskite solar cells. This study proposes the self-organization of a thin two-dimensional (2D) perovskite BA2PbBr4 layer beneath a wide-bandgap three-dimensional (3D) perovskite Cs0.17FA0.83Pb(I0.6Br0.4)3, forming a 2D/3D bilayer structure on a tin oxide (SnO2) layer. This process is driven by interactions between the oxygen vacancies on the SnO2 surface and hydrogen atoms of the n-butylammonium cation, aiding the self-assembly of the BA2PbBr4 2D layer. The 2D perovskite acts as a tunneling layer between SnO2 and the 3D perovskite, neutralizing the energy level mismatch and reducing non-radiative recombination. This results in high power conversion efficiencies of 21.54% and 19.16% for wide-bandgap perovskite solar cells with bandgaps of 1.7 and 1.8 eV, with open-circuit voltages over 1.3 V under 1-Sun illumination. Furthermore, an impressive efficiency of over 43% is achieved under indoor conditions, specifically under 200 lux white light-emitting diode light, yielding an output voltage exceeding 1 V. The device also demonstrates enhanced stability, lasting up to 1,200 hours.

7.
Adv Mater ; : e2404734, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39081101

RESUMO

The van der Waals (vdW) interface provides two important degrees of freedom-twist and slip-to tune interlayer structures and inspire unique physics. However, constructing diversified high-quality slip stackings (i.e., lattice orientations between layers are parallel with only interlayer sliding) is more challenging than twisted stackings due to angstrom-scale structural discrepancies between different slip stackings, sparsity of thermodynamically stable candidates and insufficient mechanism understanding. Here, using transition metal dichalcogenide (TMD) homobilayers as a model system, this work theoretically elucidates that vdW materials with low lattice symmetry and weak interlayer coupling allow the creation of multifarious thermodynamically advantageous slip stackings, and experimentally achieves 13 and 9 slip stackings in 1T″-ReS2 and 1T″-ReSe2 bilayers via direct growth, which are systematically revealed by atomic-resolution scanning transmission electron microscopy (STEM), angle-resolved polarization Raman spectroscopy, and second harmonic generation (SHG) measurements. This work also develops modulation strategies to switch the stacking via grain boundaries (GBs) and to expand the slip stacking library from thermodynamic to kinetically favored structures via in situ thermal treatment. Finally, density functional theory (DFT) calculations suggest a prominent dependence of the pressure-induced electronic band structure transition on stacking configurations. These studies unveil a unique vdW epitaxy and offer a viable means for manipulating interlayer atomic registries.

8.
ACS Chem Neurosci ; 15(15): 2719-2728, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39066700

RESUMO

Amyloid-ß (Aß) aggregates are recognized as initiators of Alzheimer's disease, and their interaction with the nervous system contributes to the progression of neurodegeneration. Herein, we investigated the frequency at which neuropeptides interact with Aß and affect the aggregation kinetics and cytotoxicity of Aß. To this end, we established a native mass spectrometry (MS)-centric workflow for screening Aß-interacting neuropeptides, and six out of 12 neuropeptides formed noncovalent complexes with Aß species in the MS gas phase. Thioflavin-T fluorescence assays and gel separation indicated that leptin and cerebellin decreased Aß aggregation, whereas kisspeptin increased this process. In addition, leptin and cerebellin attenuated Aß-induced cytotoxicity, which was independent of the influence of metal ions. Leptin can chelate copper from copper-bound Aß species, reducing the cytotoxicity caused by the aggregation of Aß and metal ion complexes. Overall, our study demonstrated that neuropeptides frequently interact with Aß and revealed that leptin and cerebellin are potential inhibitors of Aß aggregation, providing great insight into understanding the molecular mechanism of Aß interacting with the nervous system and facilitating drug development.


Assuntos
Peptídeos beta-Amiloides , Espectrometria de Massas , Neuropeptídeos , Peptídeos beta-Amiloides/metabolismo , Espectrometria de Massas/métodos , Humanos , Neuropeptídeos/metabolismo , Cobre/metabolismo , Leptina/metabolismo , Doença de Alzheimer/metabolismo , Animais
10.
Biomed Pharmacother ; 177: 116989, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38959609

RESUMO

The mitochondrial unfolded protein response (UPRmt) is a cytoprotective response in response to cellular stress that is activated in response to mitochondrial stress to maintain intra-protein homeostasis, thereby protecting the cell from a variety of stimuli. The activation of this response has been linked to cardiovascular diseases. Here, we reviewed the current understanding of UPRmt and discussed its specific molecular mechanism, mainly in mammals, as well as addressing its protective role against cardiovascular diseases, so as to provide direction for further research on UPRmt and therapies targeting cardiovascular diseases in the future.


Assuntos
Doenças Cardiovasculares , Mitocôndrias , Resposta a Proteínas não Dobradas , Resposta a Proteínas não Dobradas/fisiologia , Humanos , Animais , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/metabolismo , Mitocôndrias/metabolismo , Transdução de Sinais
11.
bioRxiv ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38948765

RESUMO

Modification of RNA with N6-methyladenosine (m6A) has gained attention in recent years as a general mechanism of gene regulation. In the liver, m6A, along with its associated machinery, has been studied as a potential biomarker of disease and cancer, with impacts on metabolism, cell cycle regulation, and pro-cancer state signaling. However these observational data have yet to be causally examined in vivo. For example, neither perturbation of the key m6A writers Mettl3 and Mettl14, nor the m6A readers Ythdf1 and Ythdf2 have been thoroughly mechanistically characterized in vivo as they have been in vitro. To understand the functions of these machineries, we developed mouse models and found that deleting Mettl14 led to progressive liver injury characterized by nuclear heterotypia, with changes in mRNA splicing, processing and export leading to increases in mRNA surveillance and recycling.

12.
J Mater Chem B ; 12(33): 8033-8047, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39045831

RESUMO

Biomineralization is a natural process in which organisms regulate the growth of inorganic minerals to form biominerals with unique layered structures, such as bones and teeth, primarily composed of calcium and phosphorus. Tooth decay significantly impacts our daily lives, and the key to tooth regeneration lies in restoring teeth through biomimetic approaches, utilizing mineralization strategies or materials that mimic natural processes. This review delves into the types, properties, and transformations of calcium and phosphorus minerals, followed by an exploration of the mechanisms behind physiological and pathological mineralization in living organisms. It summarizes the mechanisms and commonalities of biomineralization and discusses the advancements in dental biomineralization research, guided by insights into calcium and phosphorus mineral biomineralization. This review concludes by addressing the current challenges and future directions in the field of dental biomimetic mineralization.


Assuntos
Biomineralização , Cálcio , Fósforo , Dente , Humanos , Fósforo/química , Cálcio/metabolismo , Dente/química , Animais
13.
Asian J Androl ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39075793

RESUMO

ABSTRACT: This study assessed the feasibility of testis tissue cryopreservation (TTC) for fertility preservation in prepubescent boys with cryptorchidism. From January 2014 to December 2022, the University Hospital of Copenhagen (Rigshospitalet, Copenhagen, Denmark) implemented TTC for 56 boys with cryptorchidism to preserve their reproductive potential. Testis tissue samples were collected during orchiopexy (32 cases) or at subsequent follow-up procedures (24 cases), necessitated by an increased risk of infertility as indicated by hormonal assessments and/or findings from initial surgical biopsies. Testis samples were procured for TTC and pathological analysis. The cohort had an average age of 1.3 (range: 0.3-3.8) years at the time of orchiopexy, with 91.1% presenting bilateral cryptorchidism. The study revealed a median germ cell count of 0.39 (range: 0-2.88) per seminiferous tubule, with germ cells detected in 98.0% of the bilateral biopsies and 100% of the unilateral, indicating a substantial potential for fertility in these immature tissues. A dark spermatogonia (Ad) was detected in 37 out of 56 patients evaluated, with a median Ad spermatogonia count of 0.027 (range: 0.002-0.158) per seminiferous tubule. A total of 30.2% of the samples lacked Ad spermatogonia, indicative of potential gonadotrophin insufficiency. The median hormone levels measured were as follows: follicle-stimulating hormone (FSH) at 0.69 (range: 0.16-2.5) U l-1, luteinizing hormone (LH) at 0.21 (range: 0.05-3.86) U l-1, and inhibin B at 126 (range: 17-300) pg ml-1. Despite early orchiopexy, 20%-25% of boys with cryptorchidism remain at risk for future infertility, substantiating the necessity of TTC as a precaution. The study highlights the need for refined predictive techniques to identify boys at higher risk of future infertility.

14.
Int J Legal Med ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38858273

RESUMO

Monozygotic (MZ) twins cannot be distinguished using conventional forensic STR typing because they present identical STR genotypings. However, MZ twins do not always live in the same environment and often have different dietary and other lifestyle habits. Metabolic profiles are deyermined by individual characteristics and are also influenced by the environment in which they live. Therefore, they are potential markers capable of identifying MZ twins. Moreover, the production of proteins varies from organism to organism and is influenced by both the physiological state of the body and the external environment. Hence, we used metabolomics and proteomics to identify metabolites and proteins in peripheral blood to discriminate MZ twins. We identified 1749 known metabolites and 622 proteins in proteomic analysis. The metabolic profiles of four pairs of MZ twins revealed minor differences in intra-MZ twins and major differences in inter-MZ twins. Each pair of MZ twins exhibited distinct characteristics, and four metabolites-methyl picolinate, acesulfame, paraxanthine, and phenylbenzimidazole sulfonic acid-were observed in all four MZ twin pairs. These four differential exogenous metabolites conincidently show that the different external environments and life styles can be well distinguished by metabolites, considering that twins do not all have the same eating habits and living environments. Moreover, MZ twins showed different protein profiles in serum but not in whole blood. Thus, our results indicate that differential metabolites provide potential biomarkers for the personal identification of MZ twins in forensic medicine.

15.
Anal Chem ; 96(22): 8845, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38832809
16.
Int J Nanomedicine ; 19: 5879-5893, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895145

RESUMO

Introduction: Persistent endodontic infections (PEIs) mediated by bacterial biofilm mainly cause persistent periapical inflammation, resulting in recurrent periapical abscesses and progressive bone destruction. However, conventional root canal disinfectants are highly damaging to the tooth and periodontal tissue and ineffective in treating persistent root canal infections. Antimicrobial materials that are biocompatible with apical tissues and can eliminate PEIs-associated bacteria are urgently needed. Methods: Here, ε-poly (L-lysine) derived carbon quantum dots (PL-CQDs) are fabricated using pyrolysis to remove PEIs-associated bacterial biofilms. Results: Due to their ultra-small size, high positive charge, and active reactive oxygen species (ROS) generation capacity, PL-CQDs exhibit highly effective antibacterial activity against Enterococcus faecalis (E. faecalis), which is greatly dependent on PL-CQDs concentrations. 100 µg/mL PL-CQDs could kill E. faecalis in 5 min. Importantly, PL-CQDs effectively achieved a reduction of biofilms in the isolated teeth model, disrupting the dense structure of biofilms. PL-CQDs have acceptable cytocompatibility and hemocompatibility in vitro and good biosafety in vivo. Discussion: Thus, PL-CQDs provide a new strategy for treating E. faecalis-associated PEIs.


Assuntos
Biofilmes , Carbono , Enterococcus faecalis , Infecções por Bactérias Gram-Positivas , Polilisina , Pontos Quânticos , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/fisiologia , Pontos Quânticos/química , Biofilmes/efeitos dos fármacos , Polilisina/química , Polilisina/farmacologia , Carbono/química , Carbono/farmacologia , Animais , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/microbiologia , Antibacterianos/farmacologia , Antibacterianos/química , Humanos , Espécies Reativas de Oxigênio/metabolismo , Camundongos
17.
Adv Mater ; : e2404658, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38923073

RESUMO

Catalysts play a crucial role in water electrolysis by reducing the energy barriers for hydrogen and oxygen evolution reactions (HER and OER). Research aims to enhance the intrinsic activities of potential catalysts through material selection, microstructure design, and various engineering techniques. However, the energy consumption of catalysts has often been overlooked due to the intricate interplay among catalyst microstructure, dimensionality, catalyst-electrolyte-gas dynamics, surface chemistry, electron transport within electrodes, and electron transfer among electrode components. Efficient catalyst development for high-current-density applications is essential to meet the increasing demand for green hydrogen. This involves transforming catalysts with high intrinsic activities into electrodes capable of sustaining high current densities. This review focuses on current improvement strategies of mass exchange, charge transfer, and reducing electrode resistance to decrease energy consumption. It aims to bridge the gap between laboratory-developed, highly efficient catalysts and industrial applications regarding catalyst structural design, surface chemistry, and catalyst-electrode interplay, outlining the development roadmap of hierarchically structured electrode-based water electrolysis for minimizing energy loss in electrocatalysts for water splitting.

18.
ACS Nano ; 18(22): 14312-14326, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38767151

RESUMO

Periodontitis, a prevalent chronic inflammatory disease worldwide, is triggered by periodontopathogenic bacteria, resulting in the progressive destruction of periodontal tissue, particularly the alveolar bone. To effectively address periodontitis, this study proposed a nanoformulation known as CuS@MSN-SCS. This formulation involves coating citrate-grafted copper sulfide (CuS) nanoparticles with mesoporous silica (MSNs), followed by surface modification using amino groups and sulfated chitosan (SCS) through electrostatic interactions. The objective of this formulation is to achieve efficient bacteria removal by inducing ROS signaling pathways mediated by Cu2+ ions. Additionally, it aims to promote alveolar bone regeneration through Cu2+-induced pro-angiogenesis and SCS-mediated bone regeneration. As anticipated, by regulating the surface charges, the negatively charged CuS nanoparticles capped with sodium citrate were successfully coated with MSNs, and the subsequent introduction of amine groups using (3-aminopropyl)triethoxysilane was followed by the incorporation of SCS through electrostatic interactions, resulting in the formation of CuS@MSN-SCS. The developed nanoformulation was verified to not only significantly exacerbate the oxidative stress of Fusobacterium nucleatum, thereby suppressing bacteria growth and biofilm formation in vitro, but also effectively alleviate the inflammatory response and promote alveolar bone regeneration without evident biotoxicity in an in vivo rat periodontitis model. These findings contribute to the therapeutic effect on periodontitis. Overall, this study successfully developed a nanoformulation for combating bacteria and facilitating alveolar bone regeneration, demonstrating the promising potential for clinical treatment of periodontitis.


Assuntos
Antibacterianos , Regeneração Óssea , Quitosana , Cobre , Fusobacterium nucleatum , Nanopartículas , Periodontite , Quitosana/química , Quitosana/farmacologia , Periodontite/tratamento farmacológico , Periodontite/microbiologia , Periodontite/terapia , Periodontite/patologia , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Regeneração Óssea/efeitos dos fármacos , Ratos , Cobre/química , Cobre/farmacologia , Fusobacterium nucleatum/efeitos dos fármacos , Nanopartículas/química , Ratos Sprague-Dawley , Masculino , Sulfatos/química , Sulfatos/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Testes de Sensibilidade Microbiana
19.
ACS Appl Mater Interfaces ; 16(22): 28980-28990, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38768264

RESUMO

Freestanding single-crystalline SrTiO3 membranes, as high-κ dielectrics, hold significant promise as the gate dielectric in two-dimensional (2D) flexible electronics. Nevertheless, the mechanical properties of the SrTiO3 membranes, such as elasticity, remain a critical piece of the puzzle to adequately address the viability of their applications in flexible devices. Here, we report statistical analysis on plane-strain effective Young's modulus of large-area SrTiO3 membranes (5 × 5 mm2) over a series of thicknesses (from 6.5 to 32.2 nm), taking advantage of a highly efficient buckling-based method, which reveals its evident thickness-dependent behavior ranging from 46.01 to 227.17 GPa. Based on microscopic and theoretical results, we elucidate these thickness-dependent behaviors and statistical data deviation with a bilayer model, which consists of a surface layer and a bulk-like layer. The analytical results show that the ∼3.1 nm surface layer has a significant elastic softening compared to the bulk-like layer, while the extracted modulus of the bulk-like layer shows a variation of ∼40 GPa. This variation is considered as a combined contribution from oxygen deficiency presenting in SrTiO3 membranes, and the alignment between applied strain and the crystal orientation. Upon comparison of the extracted elastic properties and electrostatic control capability to those of other typical gate dielectrics, the superior performance of single-crystalline SrTiO3 membranes has been revealed in the context of flexible gate dielectrics, indicating the significant potential of their application in high-performance flexible 2D electronics.

20.
Neuroscience ; 549: 138-144, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38734302

RESUMO

Postoperative stroke is a challenging and potentially devastating complication after elective carotid endarterectomy (CEA). We previously demonstrated that transmembrane protein 166 (TMEM166) levels were directly related to neuronal damage after cerebral ischemia-reperfusion injury in rats. In this subsequent clinical study, we aimed to evaluate the prognostic value of TMEM166 in patients suffering from post-CEA strokes. Thirty-five patients undergoing uncomplicated elective CEA and 8 patients who suffered ischemic strokes after CEA were recruited. We evaluated the protein level and expression of TMEM166 in patients diagnosed with postoperative strokes and compared it to those in patients who underwent uncomplicated elective CEA. Blood samples and carotid artery plaques were collected and analyzed. High expressions of TMEM166 were detected by immunofluorescence staining and Western Blot in carotid artery plaques of all patients who underwent CEA. Furthermore, circulating TMEM166 concentrations were statistically higher in post-CEA stroke patients than in patients allocated to the control group. Mean plasma concentrations of inflammatory markers, including interleukin 6 (IL-6) and C-reactive protein (CRP), were also elevated in patients with postoperative strokes. Therefore, based on these findings, we hypothesize that elevated TMEM166 levels, accompanied by a strong inflammatory response, serve as a useful biomarker for risk assessment of postoperative stroke following CEA.


Assuntos
Endarterectomia das Carótidas , Proteínas de Membrana , Complicações Pós-Operatórias , Acidente Vascular Cerebral , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas/efeitos adversos , Interleucina-6/sangue , Interleucina-6/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso , Complicações Pós-Operatórias/metabolismo , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/sangue
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