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1.
Nano Lett ; 24(13): 3937-3944, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38526847

RESUMEN

Integrating high-κ dielectrics with a small equivalent oxide thickness (EOT) with two-dimensional (2D) semiconductors for low-power consumption van der Waals (vdW) heterostructure electronics remains challenging in meeting both interface quality and dielectric property requirements. Here, we demonstrate the integration of ultrathin amorphous HfOx sandwiched within vdW heterostructures by the selective thermal oxidation of HfSe2 precursors. The self-cleaning process ensures a high-quality interface with a low interface state density of 1011-1012 cm-2 eV-1. The synthesized HfOx displays excellent dielectric properties with an EOT of ∼1.5 nm, i.e., a high κ of ∼16, an ultralow leakage current of 10-6 A/cm2, and an impressively high breakdown field of 9.5 MV/cm. This facilitates low-power consumption vdW heterostructure MoS2 transistors, demonstrating steep switching with a low subthreshold swing of 61 mV/decade. This one-step integration of high-κ dielectrics into vdW sandwich heterostructures holds immense potential for developing low-power consumption 2D electronics while meeting comprehensive dielectric requirements.

2.
Mol Ther Nucleic Acids ; 35(1): 102146, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38444701

RESUMEN

Osteogenesis imperfecta (OI) is a rare genetic disease characterized by bone fragility and bone formation. Sclerostin could negatively regulate bone formation by antagonizing the Wnt signal pathway, whereas it imposes severe cardiac ischemic events in clinic. Our team has screened an aptamer that could promote bone anabolic potential without cardiovascular risk. However, the affinity of the aptamer is lower and needs to be improved. In the study, hydrophobic quinoline molecule with unique orientations (seven subtypes) were incorporated into key sites of a bone anabolic aptamer against sclerostin to form a modified aptamer library. Among all the quinoline modifications, 5-quinoline modification could shape the molecular recognition of modified aptamers to sclerostin to facilitate enhancing its binding to sclerostin toward the highest affinity by interacting with newly participated binding sites in sclerostin. Further, 5-quinoline modification could facilitate the modified aptamer attenuating the suppressed effect of the transfected sclerostin on both Wnt signaling and bone formation marker expression levels in vitro, promoting bone anabolism in OI mice (Col1a2+/G610C). The proposed quinoline-oriented modification strategy could shape the molecular recognition of modified aptamers to proteins to facilitate enhancing its binding affinity and therapeutic potency.

3.
Nano Lett ; 24(3): 975-982, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38189647

RESUMEN

Ferroelectric memristors hold immense promise for advanced memory and neuromorphic computing. However, they face limitations due to low readout current density in conventional designs with low-conductive ferroelectric channels, especially at the nanoscale. Here, we report a ferroelectric-mediated memristor utilizing a 2D MoS2 nanoribbon channel with an ultrascaled cross-sectional area of <1000 nm2, defined by a ferroelectric BaTiO3 nanoribbon stacked on top. Strikingly, the Schottky barrier at the MoS2 contact can be effectively tuned by the charge transfers coupled with quasi-zero-dimensional polarization charges formed at the two ends of the nanoribbon, which results in distinctive resistance switching accompanied by multiple negative differential resistance showing the high-current density of >104 A/cm2. The associated space charges in BaTiO3 are minimized to ∼3.7% of the polarization charges, preserving nonvolatile polarization. This achievement establishes ferroelectric-mediated nanoscale semiconductor memristors with high readout current density as promising candidates for memory and highly energy-efficient in-memory computing applications.

4.
Diabetes Obes Metab ; 26(4): 1443-1453, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38240050

RESUMEN

AIM: To assess the sex- and time-specific causal effects of obesity-related anthropometric traits on glycaemic traits. MATERIALS AND METHODS: We used univariate and multivariate Mendelian randomization to assess the causal associations of anthropometric traits (gestational variables, birth weight, childhood body mass index [BMI], BMI, waist-to-hip ratio [WHR], BMI-adjusted WHR [WHRadj BMI]) with fasting glucose and insulin in Europeans from the Early Growth Genetics Consortium (n ≤ 298 142), the UK Biobank, the Genetic Investigation of Anthropometric Traits Consortium (n ≤ 697 734; females: n ≤ 434 794; males: n ≤ 374 754) and the Meta-Analyses of Glucose and Insulin-related traits Consortium (n ≤ 151 188; females: n ≤ 73 089; males: n ≤ 67 506), adjusting for maternal genetic effects, smoking, alcohol consumption, and age at menarche. RESULTS: We observed a null association for gestational variables, a negative association for birth weight, and positive associations for childhood BMI and adult traits (BMI, WHR, and WHRadj BMI). In female participants, increased birth weight causally decreased fasting insulin (betaIVW , -0.07, 95% confidence interval [CI] -0.11 to -0.03; p = 1.92 × 10-3 ), but not glucose levels, which was annulled by adjusting for age at menarche. In male participants, increased birth weight causally decreased fasting glucose (betainverse-variance-weighted (IVW) , -0.07, 95% CI -0.11 to -0.03; p = 3.22 × 10-4 ), but not insulin levels. In time-specific analyses, independent effects of birth weight were absent in female participants, and were more pronounced in male participants. Independent effects of childhood BMI were attenuated in both sexes; independent effects of adult traits differed by sex. CONCLUSIONS: Our findings provide evidence for causal and independent effects of sex- and time-specific anthropometric traits on glycaemic variables, and highlight the importance of considering multiple obesity exposures at different time points in the life course.


Asunto(s)
Análisis de la Aleatorización Mendeliana , Obesidad , Adulto , Humanos , Masculino , Femenino , Peso al Nacer/genética , Obesidad/epidemiología , Obesidad/genética , Obesidad/complicaciones , Índice de Masa Corporal , Insulina/genética , Glucosa , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple
5.
Small ; 20(5): e2306428, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37759404

RESUMEN

Silicon (Si) is considered a promising commercial material for the next-generation of high-energy density lithium-ion battery (LIB) due to its high theoretical capacity. However, the severe volume changes and the poor conductivity hinder the practical application of Si anode. Herein, a novel core-shell heterostructure, Si as the core and V3 O4 @C as the shell (Si@V3 O4 @C), is proposed by a facile solvothermal reaction. Theoretical simulations have shown that the in-situ-formed V3 O4 layer facilitates the rapid Li+ diffusion and lowers the energy barrier of Li transport from the carbon shell to the inner core. The 3D network structure constructed by amorphous carbon can effectively improve electronic conductivity and structural stability. Benefiting from the rationally designed structure, the optimized Si@V3 O4 @C electrode exhibits an excellent cycling stability of 1061.1 mAh g-1 at 0.5 A g-1 over 700 cycles (capacity retention of 70.0%) with an average Coulombic efficiency of 99.3%. In addition, the Si@V3 O4 @C||LiFePO4 full cell shows a superior capacity retention of 78.7% after 130 cycles at 0.5 C. This study opens a novel way for designing high-performance silicon anode for advanced LIBs.

6.
J Affect Disord ; 348: 152-159, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38158048

RESUMEN

BACKGROUND: Depression is associated with both environmental tobacco smoke (ETS) and inflammation. However, whether systemic inflammation mediates the ETS-depression relationship is unclear. METHODS: We analyzed 19,612 participants from the 2009-2018 National Health and Nutrition Examination Survey (representing approximately 206,284,711 USA individuals), utilizing data of depressive symptoms (assessed by Patient Health Questionnaire-9), blood cotinine level (an ETS biomarker), dietary inflammatory index (DII, assessed by 24-h dietary recall) and inflammation, represented by immune-inflammation index (SII) and systemic inflammation response index (SIRI). RESULTS: Weighted multivariable logistic regression showed that a higher blood cotinine level is significantly associated with a higher depressive symptoms risk (OR = 1.79, 1.35-2.38). After adjusting for covariates, the effect in smokers (OR = 1.220, 95 % CI: 1.140-1.309) is larger than that in non-smokers (OR = 1.150, 95 % CI: 1.009-1.318). Compared to the lowest level, depressive symptoms risks in participants with the highest level of SII, SIRI and DII are 19 % (OR = 1.19, 1.05-1.35), 15 % (OR = 1.15, 1.01-1.31) and 88 % (OR = 1.88, 1.48-2.39) higher, respectively. Weighted linear regression demonstrated positive correlations of SII (ß = 0.004, 0.001-0.006), SIRI (ß = 0.009, 0.005-0.012) and DII (ß = 0.213, 0.187-0.240) with blood cotinine level. Restricted cubic splines model showed a linear dose-response relationship between blood cotinine and depressive symptoms (Pnon-linear = 0.410), with decreasing risk for lower DII. And SII and SIRI respectively mediate 0.21 % and 0.1 % of the association between blood cotinine and depressive symptoms. LIMITATION: Cross-sectional design, and lack of medication data for depression. CONCLUSIONS: Positive association of ETS (blood cotinine) with depressive symptoms risk is partly mediated by systemic inflammation, and anti-inflammatory diet could be beneficial.


Asunto(s)
Contaminación por Humo de Tabaco , Humanos , Contaminación por Humo de Tabaco/efectos adversos , Encuestas Nutricionales , Estudios Transversales , Depresión/epidemiología , Cotinina/análisis , Inflamación/epidemiología
7.
Small ; : e2306034, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38126675

RESUMEN

It is a huge challenge to explore how charge traps affect the electric breakdown of polymer-based dielectric composites. In this paper, alkane and aromatic molecules with different substituents are investigated according to DFT theoretical method. The combination of strong electron-withdrawing groups and aromatic rings can establish high electron affinity molecules. 4'-Nitro-4-dimethylaminoazobenzene (NAABZ) with a vertical electron affinity of 1.39 eV and a dipole moment of 10.15 D is introduced into polystyrene (PSt) to analyze the influence of charge traps on electric properties. Marcus charge transfer theory is applied to calculate the charge transfer rate between PSt and NAABZ. The nature of charge traps is elaborated from a dynamic perspective. The enhanced breakdown mechanism of polymers-based composites stems from the constraint of carrier mobility caused by the change in transfer rate. But the electrophile nature of high electron affinity filler can decrease the potential barriers at the metal-polymer interface. Simultaneously, the relationship between the electron affinity of fillers and the breakdown strength of polymer-based composites is nonlinear because of the presence of the inversion region. Based on the deep understanding of the molecular trap, this work provides the theoretical calculation for the design and development of high-performance polymer dielectrics.

8.
J Imaging ; 9(11)2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37998098

RESUMEN

To digital grade the staining color fastness of fabrics after rubbing, an automatic grading method based on spectral reconstruction technology and BP neural network was proposed. Firstly, the modeling samples are prepared by rubbing the fabrics according to the ISO standard of 105-X12. Then, to comply with visual rating standards for color fastness, the modeling samples are professionally graded to obtain the visual rating result. After that, a digital camera is used to capture digital images of the modeling samples inside a closed and uniform lighting box, and the color data values of the modeling samples are obtained through spectral reconstruction technology. Finally, the color fastness prediction model for rubbing was constructed using the modeling samples data and BP neural network. The color fastness level of the testing samples was predicted using the prediction model, and the prediction results were compared with the existing color difference conversion method and gray scale difference method based on the five-fold cross-validation strategy. Experiments show that the prediction model of fabric color fastness can be better constructed using the BP neural network. The overall performance of the method is better than the color difference conversion method and the gray scale difference method. It can be seen that the digital rating method of fabric staining color fastness to rubbing based on spectral reconstruction and BP neural network has high consistency with the visual evaluation, which will help for the automatic color fastness grading.

9.
Biomater Res ; 27(1): 86, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37715230

RESUMEN

Currently, the clinical treatment of critical bone defects attributed to various causes remains a great challenge, and repairing these defects with synthetic bone substitutes is the most common strategy. In general, tissue engineering materials that mimic the structural, mechanical and biological properties of natural bone have been extensively applied to fill bone defects and promote in situ bone regeneration. Hydrogels with extracellular matrix (ECM)-like properties are common tissue engineering materials, among which methacrylate-based gelatin (GelMA) hydrogels are widely used because of their tunable mechanical properties, excellent photocrosslinking capability and good biocompatibility. Owing to their lack of osteogenic activity, however, GelMA hydrogels are combined with other types of materials with osteogenic activities to improve the osteogenic capability of the current composites. There are three main aspects to consider when enhancing the bone regenerative performance of composite materials: osteoconductivity, vascularization and osteoinduction. Bioceramics, bioglass, biomimetic scaffolds, inorganic ions, bionic periosteum, growth factors and two-dimensional (2D) nanomaterials have been applied in various combinations to achieve enhanced osteogenic and bone regeneration activities. Three-dimensional (3D)-bioprinted scaffolds are a popular research topic in bone tissue engineering (BTE), and printed and customized scaffolds are suitable for restoring large irregular bone defects due to their shape and structural tunability, enhanced mechanical properties, and good biocompatibility. Herein, the recent progress in research on GelMA-based composite hydrogel scaffolds as multifunctional platforms for restoring critical bone defects in plastic or orthopedic clinics is systematically reviewed and summarized. These strategies pave the way for the design of biomimetic bone substitutes for effective bone reconstruction with good biosafety. This review provides novel insights into the development and current trends of research on GelMA-based hydrogels as effective bone tissue engineering (BTE) scaffolds for correcting bone defects, and these contents are summarized and emphasized from various perspectives (osteoconductivity, vascularization, osteoinduction and 3D-bioprinting). In addition, advantages and deficiencies of GelMA-based bone substitutes used for bone regeneration are put forward, and corresponding improvement measures are presented prior to their clinical application in near future (created with BioRender.com).

10.
ACS Appl Mater Interfaces ; 15(35): 41828-41838, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37632445

RESUMEN

Polymer dielectrics are crucial for use in electrostatic capacitors, owing to their high voltage resistance, high energy storage density, and ultrahigh reliability. Furthermore, high-temperature-resistant polymer dielectrics are applied in various emerging fields. Herein, poly(ether imide) (PEI)-based polymer dielectrics prepared by adding a low loading of dimethylimidazolium cobalt (ZIF-67) with a narrow bandgaps are investigated. The results show that the composites exhibit considerably increased Young's modulus, suppressed conductivity loss, and improved breakdown strength compared with pure PEI. Consequently, a stable energy storage performance is realized for ZIF-67/PEI composites. Particularly, at 150 °C, 1 wt % ZIF-67/PEI composite affords an excellent energy storage density of 4.59 J/cm3 with a discharge energy efficiency of 80.6%, exhibiting a considerable increase compared with the values obtained for PEI (2.58 J/cm3 with a discharge energy efficiency of 68.8%). The results of this study reveal a feasible pathway to design polymer dielectrics with the potential for use in capacitive applications in harsh environments.

11.
Micromachines (Basel) ; 14(4)2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37421120

RESUMEN

In this paper, the transient breakdown voltage (TrBV) of a silicon-on-insulator (SOI) laterally diffused metal-oxide-semiconductor (LDMOS) device was increased by introducing a step P-type doping buried layer (SPBL) below the buried oxide (BOX). Device simulation software MEDICI 0.13.2 was used to investigate the electrical characteristics of the new devices. When the device was turned off, the SPBL could enhance the reduced surface field (RESURF) effect and modulate the lateral electric field in the drift region to ensure that the surface electric field was evenly distributed, thus increasing the lateral breakdown voltage (BVlat). The enhancement of the RESURF effect while maintaining a high doping concentration in the drift region (Nd) in the SPBL SOI LDMOS resulted in a reduction in the substrate doping concentration (Psub) and an expansion of the substrate depletion layer. Therefore, the SPBL both improved the vertical breakdown voltage (BVver) and suppressed an increase in the specific on-resistance (Ron,sp). The results of simulations showed a 14.46% higher TrBV and a 46.25% lower Ron,sp for the SPBL SOI LDMOS compared to those of the SOI LDMOS. As the SPBL optimized the vertical electric field at the drain, the turn-off non-breakdown time (Tnonbv) of the SPBL SOI LDMOS was 65.64% longer than that of the SOI LDMOS. The SPBL SOI LDMOS also demonstrated that TrBV was 10% higher, Ron,sp was 37.74% lower, and Tnonbv was 10% longer than those of the double RESURF SOI LDMOS.

12.
Org Lett ; 25(19): 3492-3496, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37158621

RESUMEN

Photoinduced homolysis of NiII-carbon and -heteroatom bonds has been well studied for carbon-heteroatom couplings, but homolysis of the NiII-P bond is still undisclosed. Herein, we describe the homolysis of NiII-P bonds via ligand to metal charge transfer to access active nickel(I) complexes and phosphorus-centered radicals under visible-light irradiation for C-P couplings of diaryl phosphine oxides with aryl bromides. Experimental studies demonstrated that visible light enabled homolysis of the NiII-P bond and the NiI/NiIII self-sustained cycle was involved in C-P bond formation. Furthermore, homolysis of the NiII-P bond can be applied to the hydrophosphination of [1.1.1]propellane in single-nickel photocatalysis.

13.
ACS Appl Mater Interfaces ; 15(20): 24470-24482, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37170766

RESUMEN

Developing new polymer dielectrics with superior dielectric and energy storage properties is urgent to meet the demand for electronic devices in the field of microminiaturization or harsh environments. In this paper, two dipolar glass polymers based on polynorbornene main chain and flexible/rigid cyano side chain were synthesized by ring opening metathesis polymerization method: polymer PCEMT with flexible side chains and polymer PCPMT with rigid side chains. The backbone is built from two rigid five-membered rings, which not only avoids the narrow band gap caused by π-π conjugation of traditional aromatic main chains, but also maintains high thermal stability and high glass transition temperature (Tg). The introduced polar cyano groups on the side chain gave high dielectric constants (εr) for both polymers, where the εr of PCEMT and PCPMT reached 7.9 and 4.6 at room temperature and 1 kHz, respectively. Due to high polarization and high breakdown strength, the PCPMT obtains a maximum discharge energy density (Ud) of 4.47 J/cm3 at room temperature, which is 1.61 and 1.57 times of biaxially oriented polypropylene and polyimide (Kapton). The supernal Tg of 229 °C makes the energy storage performance of PCPMT almost unaffected at 100 °C. The charge-discharge efficiency (η) always keeps over 90% and an Ud of 5.2 J/cm3 at 480 MV/m is achieved, which is much better than Kapton (Ud = 1.77 J/cm3, η = 42.5%) under the same conditions. This work provides a new idea for preparing the high-performance polymer dielectrics via introducing rigid polar side chains.

14.
Psychol Med ; 53(16): 7627-7635, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37218628

RESUMEN

BACKGROUND: Observational studies suggest a correlation between post-traumatic stress disorder (PTSD) and gastrointestinal tract (GIT) disorders. However, the genetic overlap, causal relationships, and underlining mechanisms between PTSD and GIT disorders were absent. METHODS: We obtained genome-wide association study statistics for PTSD (23 212 cases, 151 447 controls), peptic ulcer disease (PUD; 16 666 cases, 439 661 controls), gastroesophageal reflux disease (GORD; 54 854 cases, 401 473 controls), PUD and/or GORD and/or medications (PGM; 90 175 cases, 366 152 controls), irritable bowel syndrome (IBS; 28 518 cases, 426 803 controls), and inflammatory bowel disease (IBD; 7045 cases, 449 282 controls). We quantified genetic correlations, identified pleiotropic loci, and performed multi-marker analysis of genomic annotation, fast gene-based association analysis, transcriptome-wide association study analysis, and bidirectional Mendelian randomization analysis. RESULTS: PTSD globally correlates with PUD (rg = 0.526, p = 9.355 × 10-7), GORD (rg = 0.398, p = 5.223 × 10-9), PGM (rg = 0.524, p = 1.251 × 10-15), and IBS (rg = 0.419, p = 8.825 × 10-6). Cross-trait meta-analyses identify seven genome-wide significant loci between PTSD and PGM (rs13107325, rs1632855, rs1800628, rs2188100, rs3129953, rs6973700, and rs73154693); three between PTSD and GORD (rs13107325, rs1632855, and rs3132450); one between PTSD and IBS/IBD (rs4937872 and rs114969413, respectively). Proximal pleiotropic genes are mainly enriched in immune response regulatory pathways, and in brain, digestive, and immune systems. Gene-level analyses identify five candidates: ABT1, BTN3A2, HIST1H3J, ZKSCAN4, and ZKSCAN8. We found significant causal effects of GORD, PGM, IBS, and IBD on PTSD. We observed no reverse causality of PTSD with GIT disorders, except for GORD. CONCLUSIONS: PTSD and GIT disorders share common genetic architectures. Our work offers insights into the biological mechanisms, and provides genetic basis for translational research studies.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Síndrome del Colon Irritable , Trastornos por Estrés Postraumático , Humanos , Trastornos por Estrés Postraumático/genética , Síndrome del Colon Irritable/genética , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Polimorfismo de Nucleótido Simple
15.
Adv Sci (Weinh) ; 10(18): e2300792, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37083243

RESUMEN

Electrostatic capacitors attract great interest in energy storage fields due to their advantages of high power-density, fast charge/discharge speed, and great reliability. Intensive efforts have been placed on the development of high-energy-density of capacitors. Herein, a novel supercapacitor with Hf0.2 Zr0.8 O2 /xAl2 O3 /Hf0.2 Zr0.8 O2 (HAHx) is designed to improve the breakdown strength (Eb ) through optimizing Al2 O3 (AO) film thickness. Low-temperature annealing is first proposed to enhance the polarization difference (Pm -Pr ) due to the formation of dispersed polar nanoregions, which is called "superparaelectric-like" similar to previous super-paraelectric behavior of perovskite structures. As results, both large Eb and Pm -Pr values are obtained, leading to an ultrahigh energy storage density of 87.66 J cm-3 with a high efficiency of 68.6%, as well as a reliable endurance of 107 cycles. This work provides a feasible pathway to improve both the polarization difference and breakdown strength of HfO2 -based films by the combination of insulation insertion layer and low-temperature annealing. The proposed strategy can contribute to the realization of high-performance electrostatic supercapacitors with excellent microsystem compatibility.


Asunto(s)
Frío , Reproducibilidad de los Resultados , Electricidad Estática , Fenómenos Físicos
16.
Bioact Mater ; 25: 594-614, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37056253

RESUMEN

Currently, implant-associated bacterial infections account for most hospital-acquired infections in patients suffering from bone fractures or defects. Poor osseointegration and aggravated osteolysis remain great challenges for the success of implants in infectious scenarios. Consequently, developing an effective surface modification strategy for implants is urgently needed. Here, a novel nanoplatform (GO/Ga) consisting of graphene oxide (GO) and gallium nanoparticles (GaNPs) was reported, followed by investigations of its in vitro antibacterial activity and potential bacterium inactivation mechanisms, cytocompatibility and regulatory actions on osteoblastogenesis and osteoclastogenesis. In addition, the possible molecular mechanisms underlying the regulatory effects of GO/Ga nanocomposites on osteoblast differentiation and osteoclast formation were clarified. Moreover, an in vivo infectious microenvironment was established in a rat model of implant-related femoral osteomyelitis to determine the therapeutic efficacy and biosafety of GO/Ga nanocomposites. Our results indicate that GO/Ga nanocomposites with excellent antibacterial potency have evident osteogenic potential and inhibitory effects on osteoclast differentiation by modulating the BMP/Smad, MAPK and NF-κB signaling pathways. The in vivo experiments revealed that the administration of GO/Ga nanocomposites significantly inhibited bone infections, reduced osteolysis, promoted osseointegration located in implant-bone interfaces, and resulted in satisfactory biocompatibility. In summary, this synergistic therapeutic system could accelerate the bone healing process in implant-associated infections and can significantly guide the future surface modification of implants used in bacteria-infected environments.

17.
Front Cell Dev Biol ; 11: 1091809, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36910146

RESUMEN

Nucleic acid aptamers are ssDNA or ssRNA fragments that specifically recognize targets. However, the pharmacodynamic properties of natural aptamers consisting of 4 naturally occurring nucleosides (A, G, C, T/U) are generally restricted for inferior binding affinity than the cognate antibodies. The development of high-affinity modification strategies has attracted extensive attention in aptamer applications. Chemically modified aptamers with stable three-dimensional shapes can tightly interact with the target proteins via enhanced non-covalent bonding, possibly resulting in hundreds of affinity enhancements. This review overviewed high-affinity modification strategies used in aptamers, including nucleobase modifications, fluorine modifications (2'-fluoro nucleic acid, 2'-fluoro arabino nucleic acid, 2',2'-difluoro nucleic acid), structural alteration modifications (locked nucleic acid, unlocked nucleic acid), phosphate modifications (phosphorothioates, phosphorodithioates), and extended alphabets. The review emphasized how these high-affinity modifications function in effect as the interactions with target proteins, thereby refining the pharmacodynamic properties of aptamers.

18.
Environ Sci Pollut Res Int ; 30(22): 63272-63288, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36961639

RESUMEN

The environment is the foundation for human existence, and the digital economy has exacerbated the impact of human beings on the environment. Based on data of 31 provinces in China from 2011 to 2020, we used the spatial Durbin model to research the impact of the digital economy on the environment and its spatiotemporal characteristics. We found that the digital economy has a significant positive impact on the environmental effects of the region, and also has a positive spatial overflow. This conclusion still holds after robustness test and endogenous treatment (changing the space weight matrix, applying the instrumental variables, and two-stage least-squares method). Second, we found that environmental effects of the digital economy have a time lag, and the lag decreases gradually over time. Third, we used geographically and temporally weighted regression model and K-means clustering, which shows that digital economy has a strong effect on the environment in western region. The western region may need to increase digital infrastructure construction to achieve better environmental effects. In addition, China needs to upgrade its industrial structure as soon as possible, accelerate technological innovation, and advocate a green lifestyle, so as to realize the coordinated development of human beings and nature.


Asunto(s)
Clima , Industrias , Humanos , China , Análisis por Conglomerados , Desarrollo Económico , Ciudades
19.
Small ; 19(26): e2300510, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36929673

RESUMEN

It is urgent to develop high-temperature dielectrics with high energy density and high energy efficiency for next-generation capacitor demands. Metal-organic frameworks (MOFs) have been widely used due to their structural diversity and functionally adaptable properties. Doping of metal nodes in MOFs is an effective strategy to change the band gap and band edge positions of the original MOFs, which helps to improve their ability to bind charges as traps. In this work, the incorporation of ultralow loading (<1.5 wt%) of novel bimetallic MOFs (ZIF 8-67) into the polyetherimide (PEI) polymer matrix is exhibited. With the addition of ZIF 8-67, the breakdown strength and energy storage capacity of ZIF 8-67/PEI nanocomposites are significantly improved, especially at high temperatures (200 °C). For example, the energy densitiy of the 0.5 wt% ZIF 8-67/PEI nanocomposite is up to 2.96 J cm-3 , with an efficiency (η) > 90% at 150 °C. At 200 °C, the discharge energy density of 0.25 wt% ZIF 8-67/PEI nanocomposites can still reach 1.84 J cm-3 with a η > 90%, which is nine times higher than that of pure PEI (0.21 J cm-3 ) under the same conditions, and it is the largest improvement compared with the previous reports.

20.
ACS Appl Mater Interfaces ; 15(3): 4166-4174, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36648025

RESUMEN

As one of the promising anode materials, silicon has attracted much attention due to its high theoretical specific capacity (∼3579 mAh g-1) and suitable lithium alloying voltage (0.1-0.4 V). Nevertheless, the enormous volume expansion (∼300%) in the process of lithium alloying has a great negative effect on its cyclic stability, which seriously restricts the large-scale industrial preparation of silicon anodes. Herein, we design a facile synthesis strategy combining vanadium doping and carbon coating to prepare a silicon-based composite (V-Si@C). The prepared V-Si@C composite does not merely show improved conductivity but also improved electrochemical kinetics, attributed to the enlarged lattice spacing by V doping. Additionally, the superiority of this doping strategy accompanied by microstructure change is embodied in the relieved volume changes during the repeated charging/discharging process. Notably, the initial capacity of the advanced V-Si@C electrode is 904 mAh g-1 (1 A g-1) and still holds at 1216 mAh g-1 even after 600 cycles, showing superior electrochemical performance. This study offers an alternative direction for the large-scale preparation of high-performance silicon-based anodes.

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