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1.
J Chem Inf Model ; 64(9): 3599-3604, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38620066

RESUMEN

Understanding tautomerism and characterizing solvent effects on the dynamic processes pose significant challenges. Using enhanced-sampling molecular dynamics based on state-of-the-art deep learning potentials, we investigated the tautomeric equilibria of glycine in water. We observed that the tautomerism between neutral and zwitterionic glycine can occur through both intramolecular and intermolecular proton transfers. The latter proceeds involving a contact anionic-glycine-hydronium ion pair or separate cationic-glycine-hydroxide ion pair. These pathways with comparable barriers contribute almost equally to the reaction flux.


Asunto(s)
Glicina , Simulación de Dinámica Molecular , Solventes , Agua , Glicina/química , Agua/química , Solventes/química , Isomerismo , Protones , Conformación Molecular
2.
Polymers (Basel) ; 16(7)2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38611245

RESUMEN

The noticeable difference in the coefficient of thermal expansion (CTE) for polytetrafluoroethylene (PTFE) coatings and copper substrates is a major challenge for thermal debonding of the copper-clad laminate (CCL) in high-frequency communications. Theoretically, ceramic fillers with low CTEs in the coating can effectively reduce the gap, and there remains a trade-off between the dispersibility of fillers and the interfacial interactions with the polymeric matrix. Here, we propose a novel approach to prepare a pentafluorobenzoyl chloride (PFBC)-modified polydopamine (PDA) shell on silica particles by using amidation. Such modified particles perform excellent dispersion and exhibit diminished interfacial gaps in the PTFE matrix, which highly reduces CTE to 77 ppm/°C, accounting for only 48.1% of the neat coating. Moreover, the composite exhibits enhanced mechanical strength and toughness, and consequently suppresses thermal debonding in CCL under high-temperature conditions. Therefore, results present a promising potential for its use in the next-generation CCL of high-frequency communication devices.

3.
ACS Appl Mater Interfaces ; 16(11): 14162-14170, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38469738

RESUMEN

High-performance dielectric nanocomposites are promising candidates for thin-film dielectric capacitors for high-power pulse devices. However, the existing nanocomposites suffer from low charge-discharge efficiency (η), which results in severe generation and accumulation of Joule heat and subsequently the failure of the devices. In this work, we report nacre-inspired dielectric nanocomposites with outstanding η, which are enabled by superspreading shear flow-induced highly aligned two-dimensional (2D) nanofillers. Taking boron nitride nanosheets (BNNS) as an example, the highly aligned BNNS in the poly(vinylidene fluoride) (PVDF)-based nanocomposites contributes to a highly efficient Coulomb blockade effect for the injected charge carriers. Therefore, the bioinspired nanocomposites with highly aligned BNNS show significantly reduced dielectric loss (tan δ) (63.3%) and improved η (144.8%), compared to the ones with partially aligned nanosheets fabricated by solution casting. Furthermore, the optimized loading content of BNNS is as low as 3.6 wt %. The resulting nanocomposites exhibit reduced tan δ (0.018) and enhanced Eb (687 kV/mm), η (71%), and Ue (16.74 J/cm3). Our work demonstrates that the realization of high alignment of 2D nanofillers enabled by the superspreading shear flow is a promising way for the development of high-performance dielectric nanocomposites.

4.
Small ; : e2311219, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38263800

RESUMEN

The development of thermally stable separators is a promising approach to address the safety issues of lithium-ion batteries (LIBs) owing to the serious shrinkage of commercial polyolefin separators at elevated temperatures. However, achieving controlled nanopores with a uniform size distribution in thermostable polymeric separators and high electrochemical performance is still a great challenge. In this study, nanoporous polyimide (PI) membranes with excellent thermal stability as high-safety separators is developed for LIBs using a superspreading strategy. The superspreading of polyamic acid solutions enables the generation of thin and uniform liquid layers, facilitating the formation of thin PI membranes with controllable and uniform nanopores with narrow size distribution ranging from 121 ± 5 nm to 86 ± 6 nm. Such nanoporous PI membranes display excellent structural stability at elevated temperatures up to 300 °C for at least 1 h. LIBs assembled with nanoporous PI membranes as separators show high specific capacity and Coulombic efficiency and can work normally after transient treatment at a high temperature (150 °C for 20 min) and high ambient temperature, indicating their promising application as high-safety separators for rechargeable batteries.

5.
ChemSusChem ; : e202301725, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38225682

RESUMEN

Rechargeable aluminum battery (RAB) is expected to be a promising energy storage technique for grid-scale energy storage. However, the development of RABs is seriously plagued by the lack of suitable cathode materials. Herein, we report two p-type conjugated polymers of L-PBPz and C-PBPz with the same building blocks of diphenylphenazine but different linkage patterns of linear and crosslinked structures as the cathode materials for Al dual-ion batteries. Compared to the linear polymer skeleton in L-PBPz, the crosslinked structure endows C-PBPz with amorphous nature and low dihedral angles of the polymer chains, which severally contribute to the fast diffusion of AlCl4 - with large size and the electron transfer during the redox reaction of diphenylphenazine. As a result, C-PBPz delivers a much better rate performance than L-PBPz. The crosslinked structure also leads to a stable cyclability with over 80000 cycles for C-PBPz. Benefiting from the fast kinetics, meanwhile, the C-PBPz cathode could realize a high redox activity of 117 mAh g-1 , corresponding to an areal capacity of 2.30 mAh cm-2 , even under a high mass loading of 19.7 mg cm-2 and a low content of 10 wt% conductive agent. These results might boost the development of polymer cathodes for RABs.

6.
Int J Nurs Pract ; 30(2): e13211, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37798948

RESUMEN

AIM: We aimed to assess the impact of Tai Chi interventions on individuals with essential hypertension and to compare the effects of Tai Chi versus control in this population. BACKGROUND: Tai Chi has been extensively utilized in the prevention of essential hypertension. Nevertheless, there is a lack of consensus regarding its benefits for treating essential hypertension. DESIGN: A systematic review and meta-analysis was conducted. DATA SOURCES: We conducted a systematic literature search of the Medline, Scholar, Elsevier, Wiley Online Library, Chinese Academic Journal (CNKI) and Wanfang databases from January 2003 to August 2023. REVIEW METHODS: Using the methods of the Cochrane Collaboration Handbook, a meta-analysis was conducted to assess the collective impact of Tai Chi exercise in controlling hypertension. The primary outcomes measured included blood pressure and nitric oxide levels. RESULTS: The participants consisted of adults with an average age of 57.1 years who had hypertension (mean ± standard deviation systolic blood pressure at 148.2 ± 12.1 mmHg and diastolic blood pressure at 89.2 ± 8.3 mmHg). Individuals who practiced Tai Chi experienced reductions in systolic blood pressure of 10.6 mmHg, diastolic blood pressure of 4.7 mmHg and an increase in nitric oxide levels. CONCLUSIONS: Tai Chi can be a viable lifestyle intervention for managing hypertension. Greater promotion of Tai Chi by medical professionals could extend these benefits to a larger patient population.


Asunto(s)
Hipertensión , Taichi Chuan , Adulto , Humanos , Persona de Mediana Edad , Taichi Chuan/métodos , Óxido Nítrico , Hipertensión Esencial/terapia , Hipertensión/prevención & control , Presión Sanguínea
7.
Sensors (Basel) ; 23(23)2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38067831

RESUMEN

In recent years, deep convolutional neural networks (CNNs) have made significant progress in single-image super-resolution (SISR) tasks. Despite their good performance, the single-image super-resolution task remains a challenging one due to problems with underutilization of feature information and loss of feature details. In this paper, a multi-scale recursive attention feature fusion network (MSRAFFN) is proposed for this purpose. The network consists of three parts: a shallow feature extraction module, a multi-scale recursive attention feature fusion module, and a reconstruction module. The shallow features of the image are first extracted by the shallow feature extraction module. Then, the feature information at different scales is extracted by the multi-scale recursive attention feature fusion network block (MSRAFFB) to enhance the channel features of the network through the attention mechanism and fully fuse the feature information at different scales in order to improve the network's performance. In addition, the image features at different levels are integrated through cross-layer connections using residual connections. Finally, in the reconstruction module, the upsampling capability of the deconvolution module is used to enlarge the image while extracting its high-frequency information in order to obtain a sharper high-resolution image and achieve a better visual effect. Through extensive experiments on a benchmark dataset, the proposed network model is shown to have better performance than other models in terms of both subjective visual effects and objective evaluation metrics.

8.
Nanomaterials (Basel) ; 13(20)2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37887921

RESUMEN

The distinctive cage-like structure of polyhedral oligomeric silsesquioxane (POSS) materials makes them highly effective fillers in composite membranes for separation applications. However, realizing their full potential in the application often requires specific surface functionalization with various groups. However, this requirement remains challenging owing to the limitations of wet-chemistry approaches, which frequently result in the generation of hazardous chemical by-products. In this paper, a "green" stirring plasma strategy is presented for the functionalization of octa-methyl POSS sub-micron particles into designable oxygen-containing functional groups using a low-pressure oxygen plasma from combined continuous wave and pulsed (CW+P) modes. Plasma from oxygen gas with CW mode offers highly oxygen-reactive species to continuously etch and activate the surface of the POSS. The resulting pulsed plasma assists in grafting more reactive oxygen species onto the active methyl groups of the POSS to form specific oxygen-containing functional groups including hydroxyl and carboxyl. A precise control of nearly one hydroxyl or one carboxyl group at the corner of the cage structure of the POSS is demonstrated, without damaging the core. Therefore, the plasma process discussed in this work is suggested by the authors as controllable fundamental research for the surface functionalization of sub-micron particles, promoting a more environmentally friendly pathway for the preparation of designable fillers.

9.
Heliyon ; 9(10): e20189, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37810800

RESUMEN

Demand response (DR) is one of the most effective and economical methods for power operators to improve network reliability in face of uncertainty and emergencies. In this paper, considering the uncertainty of wind power output and the failure of power system components, a two-stage security-constrained unit commitment (SCUC) model is established by optimizing the real-time pricing mechanism to indirectly adjust the DR. Firstly, the uncertainty of wind power output is modeled based on self-organizing map (SOM), and the component failure of the power system is modeled based on Monte Carlo. Then, a pricing scheme is proposed to stimulate users' electricity consumption behavior. Finally, the marine predator algorithm is used to solve the problem. Simulation results on IEEE-RTS system show that the proposed method can reduce the total operating cost by 10%, effectively stimulate the electricity consumption behavior of users, to improve the peak load shifting and valley filling capacity of the power system.

10.
J Hematol Oncol ; 16(1): 97, 2023 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-37596653

RESUMEN

Adoptive cell therapies (ACTs) have existed for decades. From the initial infusion of tumor-infiltrating lymphocytes to the subsequent specific enhanced T cell receptor (TCR)-T and chimeric antigen receptor (CAR)-T cell therapies, many novel strategies for cancer treatment have been developed. Owing to its promising outcomes, CAR-T cell therapy has revolutionized the field of ACTs, particularly for hematologic malignancies. Despite these advances, CAR-T cell therapy still has limitations in both autologous and allogeneic settings, including practicality and toxicity issues. To overcome these challenges, researchers have focused on the application of CAR engineering technology to other types of immune cell engineering. Consequently, several new cell therapies based on CAR technology have been developed, including CAR-NK, CAR-macrophage, CAR-γδT, and CAR-NKT. In this review, we describe the development, advantages, and possible challenges of the aforementioned ACTs and discuss current strategies aimed at maximizing the therapeutic potential of ACTs. We also provide an overview of the various gene transduction strategies employed in immunotherapy given their importance in immune cell engineering. Furthermore, we discuss the possibility that strategies capable of creating a positive feedback immune circuit, as healthy immune systems do, could address the flaw of a single type of ACT, and thus serve as key players in future cancer immunotherapy.


Asunto(s)
Neoplasias Hematológicas , Receptores Quiméricos de Antígenos , Humanos , Inmunoterapia Adoptiva , Inmunoterapia , Ingeniería Celular
11.
Polymers (Basel) ; 15(13)2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37447551

RESUMEN

Ultrathin hydrogel films composed of cross-linked polymer networks swollen by water, with soft and moisturized features similar to biological tissue, play a vital role in flexible biosensors and wearable electronics. However, achieving efficient and continuous fabrication of such films remains a challenge. Here, we present a microfluidic-based strategy for the continuous fabrication of free-standing ultrathin hydrogel films by using laminar flow, which can be precisely controlled in the micrometer scale. Compared with conventional methods, the microfluidic-based method shows advantages in producing hydrogel films with a high homogeneity as well as maintaining the structural integrity, without the need of supporting substrates and sophisticated equipment. This strategy allows the precise control over the thickness of the hydrogel films ranging from 15 ± 0.2 to 39 ± 0.5 µm, by adjusting the height of the microfluidic channels, with predictable opportunities for scaling up. Therefore, our strategy provides a facile route to produce advanced thin polymer films in a universal, steerable, and scalable manner and will promote the applications of thin polymer films in biosensors and wearable electronics.

12.
Environ Res ; 232: 116311, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37290622

RESUMEN

The organic pollutants in industrial wastewater continuously endanger human health. Therefore, effective treatment of organic pollutants is very urgent. Photocatalytic degradation technology is an excellent solution to remove it. TiO2 photocatalysts are easy to prepare and have high catalytic activity, unfortunately, TiO2 only absorbs ultraviolet light limiting its utilization of visible light. In this study, a facile environmentally friendly synthesis of Ag-coated on micro-wrinkled TiO2-based catalysts in order to extend the absorption of Visible light. Firstly, a fluorinated titanium dioxide precursor was prepared by a one-step solvothermal method, and the precursor was calcined at high temperature in a nitrogen atmosphere to form a carbon dopant, and then a surface silver-deposited carbon/fluorine co-doped TiO2 photocatalyst C/F-Ag-TiO2 was prepared by a hydrothermal method The results showed that the Ag was coated on the wrinkled TiO2 layer and C/F-Ag-TiO2 photocatalyst was synthetized successfully. Benefit from the synergistic effect of doped carbon and fluorine atoms in combination with the quantum size effect of the surface silver nanoparticles, the band gap energy of C/F-Ag-TiO2 (2.56 eV) is obviously lower than anatase (3.2eV). The photocatalyst achieved an impressive degradation rate of 84.2% for Rhodamine B in 4 h, with a degradation rate constant of 0.367 h-1, which was 17 times higher than that of P25 under visible light. Therefore, the C/F-Ag-TiO2 composite is a promising candidate as a highly efficient photocatalyst for environmental remediation.


Asunto(s)
Contaminantes Ambientales , Nanopartículas del Metal , Humanos , Plata , Flúor , Luz , Titanio , Carbono , Catálisis
14.
Chem Commun (Camb) ; 59(41): 6235-6238, 2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37132188

RESUMEN

We report here 4,4-bis(2-ethylhexyl)-4H-silolo[3,2-b:4,5-b']dithiophene (SiDT) as an electron donor to construct a donor-acceptor type conjugated polymer (PSiDT-BTDO) photocatalyst with a narrow band gap by employing dibenzo[b,d]thiophene-S,S-dioxide as an electron acceptor. The resulting polymer PSiDT-BTDO could realize a high hydrogen evolution rate of 72.20 mmol h-1 g-1 under ultraviolet-visible light with a Pt co-catalyst, due to the enhanced hydrophilicity as well as the decreased recombination rate of photo-induced holes/electrons and the dihedral angles of the polymer chains. The high photocatalytic activity of PSiDT-BTDO reveals the promising application of the SiDT donor in designing high-performance organic photocatalysts for hydrogen evolution.

15.
Small Methods ; : e2300221, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37254259

RESUMEN

Directional liquid spreading has an irreplaceable role in applications such as microfluidic devices, disposable biosensors, and point-of-care diagnostics. However, how to achieve directional, rapid, and complete spreading (i.e., superspreading) of liquids without external energy input is a great challenge. Herein, inspired by the peristome surface of Nepenthes pitcher, the directional superspreading of water droplets on hydrogel surfaces with predesigned microchannels by using the synergistic effect of the liquid-like property of hydrogels and the guidance of anisotropic microstructures is reported. Compared with the smooth ones, hydrogel surfaces with isotropic microstructures can facilitate the superspreading of water droplets, which can be realized within 500 ms in the absence of external forces. Furthermore, directional superspreading and the flow of water droplets are realized under the guidance of anisotropic microgrooves. Such a unique spreading behavior can also be observed on the hydrogel surfaces with various shaped microchannels, such as periodic, bent, shunted, divergent, and confluent morphologies, which have potential for the development of open microfluidic platforms for various healthcare-related applications.

16.
Cell Death Dis ; 14(5): 333, 2023 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-37210387

RESUMEN

Unbalanced protein homeostasis (proteostasis) networks are frequently linked to tumorigenesis, making cancer cells more susceptible to treatments that target proteostasis regulators. Proteasome inhibition is the first licensed proteostasis-targeting therapeutic strategy, and has been proven effective in hematological malignancy patients. However, drug resistance almost inevitably develops, pressing for a better understanding of the mechanisms that preserve proteostasis in tumor cells. Here we report that CD317, a tumor-targeting antigen with a unique topology, was upregulated in hematological malignancies and preserved proteostasis and cell viability in response to proteasome inhibitors (PIs). Knocking down CD317 lowered Ca2+ levels in the endoplasmic reticulum (ER), promoting PIs-induced proteostasis failure and cell death. Mechanistically, CD317 interacted with calnexin (CNX), an ER chaperone protein that limits calcium refilling via the Ca2+ pump SERCA, thereby subjecting CNX to RACK1-mediated autophagic degradation. As a result, CD317 decreased the level of CNX protein, coordinating Ca2+ uptake and thus favoring protein folding and quality control in the ER lumen. Our findings reveal a previously unrecognized role of CD317 in proteostasis control and imply that CD317 could be a promising target for resolving PIs resistance in the clinic.


Asunto(s)
Antígeno 2 del Estroma de la Médula Ósea , Inhibidores de Proteasoma , Proteostasis , Humanos , Calnexina/metabolismo , Supervivencia Celular , Chaperonas Moleculares/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Inhibidores de Proteasoma/farmacología , Receptores de Cinasa C Activada/genética , Receptores de Cinasa C Activada/metabolismo , Antígeno 2 del Estroma de la Médula Ósea/genética , Antígeno 2 del Estroma de la Médula Ósea/metabolismo
17.
Chemistry ; 29(39): e202301163, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37093547

RESUMEN

Achieving efficient separation of mono-/multivalent metal ions is essential in various fields, yet it remains a significant challenge. In this work, a metal-organic framework (MOF) array with subnanochannels that exhibit high selectivity and ion permeability in the sieving of mono-/multivalent metal ion was developed. Specifically, we used confined interfacial reaction at room temperature to synthesis the MOF array inside the micrometer through-pores of a polyethylene terephthalate (PET) membrane. The location of the oil/water interface was regulated by adjusting the surface wettability of the PET membrane. By taking advantage of size sieving effect of the subnanochannels of MOF crystals, we were able to effectively separate monovalent metal ions from multivalent metal ions with selectivity reaching up to 3930±373 (e.g., Li+ /Zr4+ ). The fluxes of Li+ ions were observed to be as high as 1.97 mol h-1 m-2 . The MOF array-based membrane with subnanochannels that we have developed exhibits great promise for applications in wastewater treatment, lithium extraction from salt-lake brines, and other related fields.

19.
Adv Sci (Weinh) ; 10(8): e2204544, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36658690

RESUMEN

Dendritic cell (DC) migration is a fundamental step during execution of its adaptive immunity functions. Studying DC migration characteristics is critical for development of DC-dependent allergy treatments, vaccines, and cancer immunotherapies. Here, a microfluidics-based single-cell migration platform is described that enables high-throughput and precise bidirectional cell migration assays. It also allows selective retrieval of cell subpopulations that have different migratory potentials. Using this microfluidic platform, DC migration is investigated in response to different chemoattractants and inhibitors, quantitatively describe DC migration patterns and retrieve DC subpopulations of different migratory potentials for differential gene expression analysis. This platform opens an avenue for precise characterization of cell migration and potential discovery of therapeutic modulators.


Asunto(s)
Inmunidad Adaptativa , Células Dendríticas , Movimiento Celular , Microfluídica , Inmunoterapia
20.
Angew Chem Int Ed Engl ; 62(2): e202215906, 2023 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-36374215

RESUMEN

Biological ion channels penetrated through cell membrane form unique transport pathways for selective ionic conductance. Replicating the success of ion selectivity with mixed matrix membranes (MMMs) will enable new separation technologies but remains challenging. Herein, we report a soft substrate-assisted solution casting method to develop MMMs with penetrating subnanochannels for selective metal ion conduction. The MMMs are composed of penetrating Prussian white (PW) microcubes with subnanochannels in dense polyimide (PI) matrices, achieving selective monovalent metal ion conduction. The ion selectivity of K+ /Mg2+ is up to 14.0, and the ion conductance of K+ can reach 45.5 µS with the testing diameter of 5 mm, which can be further improved by increasing the testing area. Given the diversity of nanoporous materials and polymer matrices, we expect that the MMMs with penetrating subnanochannels could be developed into a versatile nanofluidic platform for various emerging applications.


Asunto(s)
Metales , Nanoporos , Membrana Celular , Iones , Polímeros
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