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1.
Adv Sci (Weinh) ; : e2403551, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38868953

RESUMO

With the onset of the 5G era, wearable flexible electronic devices have developed rapidly and gradually entered the daily life of people. However, the vast majority of research focuses on the integration of functions and performance improvement, while ignoring electromagnetic hazards caused by devices. Herein, the 3D double conductive networks are constructed through a repetitive vacuum-assisted dip-coating technique to decorate the 2D MXene and 1D silver nanowires on the melamine foam. Benefiting from the unique porous structure and multi-scale interconnected frame, the resultant composite foam exhibited high electrical conductivity, low density, superb electromagnetic interference shielding (48.32 dB), and Joule heating performance (up to 90.8 °C under 0.8 V). Furthermore, a single-electrode triboelectric nanogenerator (TENG) with powerful energy harvesting capability is assembled by combining the composite foam with an ultra-thin Ecoflex film and a polyvinylidene fluoride film. Simultaneously, the foam-based TENG can also be considered a reliable wearable sensor for monitoring activity patterns in different parts of the human body. The versatility and scalable manufacturing of high-performance composite foams will provide new design ideas for the development of next-generation flexible wearable devices.

2.
Carbohydr Polym ; 329: 121777, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38286548

RESUMO

Developing high-performance microwave absorption (MA) materials becomes an urgent concern in the field of electromagnetic protection. Constructing porous framework is an efficient approach to MA owing to the abilities of adjusting impedance matching and providing more reflection and scattering paths for electromagnetic waves. Herein, a cellulose nanofibril (CNF)/honeycomb-like carbon-shell encapsulated FeCoNi@C/carbon nanotube (CNT) composite aerogel was fabricated via a facile freeze-drying method. The super-lightweight composites showed a distinctive gradient structure for reflection and scattering inside aerogel pores, micrometer small pores, and nano-fillers on the pore walls. The composite aerogel showed an ideal minimum reflection loss (RLmin) of -43.6 dB and remarkable adjustable effective absorption bandwidth (EAB) of 12.18 GHz due to good impedance matching, unique gradient porous structure, and synergies of multiple loss mechanisms. Therefore, this work will provide a viable strategy to improve the MA capability of absorbers by taking full advantage of constructing gradient reflection and scattering porous structure.

3.
Int J Biol Macromol ; 258(Pt 1): 128855, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38114002

RESUMO

Conductive hydrogels have received widespread attention in the field of flexible sensors. However, a single network structure inside the hydrogel sensor usually makes it difficult to bear larger mechanical loadings, greatly limiting practical applications. Developing a recoverable conductive hydrogel sensor with high toughness and adaptability is still challenging. Herein, a high-performance polyvinyl alcohol (PVA)-based conductive composite hydrogel was constructed, assisted by green cellulose nanofibrils (CNFs), magnesium chloride (MgCl2), ethylene glycol (EG), and liquid metal (LM). The synergistic effects between CNFs and LM enhanced the network structure inside the recoverable hydrogel. This resulted in an excellent tensile strength of 3.86 MPa with an elongation at break of as high as 918.4 % and compressive strength of 4.04 MPa at 80 % strain. In addition, the conductive network composed of MgCl2 and LM endowed the hydrogel good electrical conductivity. Moreover, it could be used as a flexible strain sensor for various application scenarios, e.g., micro-stress monitoring (water droplet falling) and information encryption transmission of Morse code. Such uniqueness will provide a design strategy for developing a new generation of hydrogel sensors.


Assuntos
Celulose , Álcool de Polivinil , Condutividade Elétrica , Hidrogéis , Metais
4.
J Colloid Interface Sci ; 650(Pt A): 437-445, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37418894

RESUMO

Two-dimensional (2D) MXene has attracted vast attention in electromagnetic wave absorption (EWA), but there remains a contradiction between maintaining impedance matching and enhancing dielectric loss. Herein, the multi-scale architectures of ecoflex/2D MXene (Ti3C2Tx)@zero-dimensional CoNi sphere@one-dimensional carbon nanotube composite elastomers were successfully constructed by simple liquid-phase reduction and thermo-curing method. The binding between the hybrids as fillers and ecoflex as a matrix greatly enhanced the EWA capability of the obtained composite elastomer and improved its mechanical properties. Owing to its good impedance matching, abundant heterostructures, and synergistic electrical and magnetic losses, this elastomer exhibited an excellent minimum reflection loss of -67 dB at 9.46 GHz under a thickness of 2.98 mm. In addition, its ultrabroad effective absorption bandwidth reached 6.07 GHz. This achievement will pave the way for the exploitation of multi-dimensional heterostructures as high-performance electromagnetic absorbers with superior EWA ability.

5.
J Colloid Interface Sci ; 649: 394-402, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37354796

RESUMO

Nowadays, developing high-performance electromagnetic functional materials to eliminate the ever-increasing electromagnetic pollution problem is necessary for the complex electromagnetic environment. However, the materials with high electrical conductivity are prone to secondary electromagnetic pollution due to interface impedance mismatching. Herein, the wheat-like electrically conductive and magnetic silver nanowire@nickle (AgNW@Ni) composites were fabricated via a one-pot in-situ growth method. The electromagnetic properties of the composites could be regulated by adjusting different ratios of precursors, resulting in various morphological features of the nanowire as the core with different Ni shell thicknesses. When the Ag and Ni molar ratio was 1:1.1, the AgNW@Ni composite exhibited the optimal minimum reflection loss (RLmin) of -61.1 dB with an adequate effective absorption bandwidth (EAB) of 4.06 GHz owing to good impedance matching, abundant heterostructures, and synergistic electrical and magnetic losses. Even after three months, it still maintained an acceptable RLmin value of -39.7 dB and similar EAB, demonstrating its long-term operational stability. This unique composite is expected to be applied in more actual electromagnetic protection occasions.

6.
Int J Biol Macromol ; 230: 123117, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36603716

RESUMO

Wearable flexible sensors based on conductive hydrogels have received extensive attention in the fields of electronic skin and smart monitoring. However, conductive hydrogels contain a large amount of water, which greatly affects their performances in harsh environments. It is therefore necessary to prepare hydrogel sensors that are stable at low temperatures. Herein, metal ions (MgCl2) and ethylene glycol (EG) were combined with polyvinyl alcohol (PVA) to obtain a conductive PVA/EG hydrogel with tensile strength and elongation at break of 1.1 MPa and 442.3 %, respectively, which could withstand >6000-fold its own weight. The binary solvent system composed of water and EG contributed to the excellent anti-freezing properties and long-term storage (>1 week), flexibility, and stability of the hydrogel even at -20 °C. The wearable PVA/EG hydrogel as a flexible sensor possessed desirable sensing performances with a competitive GF value of 0.725 and fatigue resistance (50 cycles) when used to monitor various human motions and physiological signals. Overall, this hydrogel sensor shows strong potential for application in the fields of human motion monitoring, written information sensing, and information encryption and transmission.


Assuntos
Temperatura Baixa , Hidrogéis , Humanos , Condutividade Elétrica , Água , Etilenoglicóis
7.
Molecules ; 27(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36558103

RESUMO

Recently, the sustainable utilization of waste resources has become a low-cost and effective strategy to design high-performance functional materials to solve the increasingly serious environmental pollution problem. Herein, the flexible and highly stretchable polyurethane (PU) composite foams assisted by one-dimensional carbon nanotubes (CNTs) and zero-dimensional Fe3O4 were fabricated using waste tire rubbers (WTRs) as reinforcements during a simple self-foaming process. The collaborative introduction of conductive CNTs, magnetic Fe3O4, and WTRs with three-dimensional cross-linked structures enabled the construction of an efficient electronic transmission path and heterointerfaces inside the composite foam. The resulting composite foam possessed a desired minimum reflection loss (RLmin) of −47.43 dB, and also exhibited superior mechanical properties with a tensile strength of >3 MPa and multiple tensile deformation recovery abilities. In addition, increasing the temperature could significantly improve the electromagnetic wave absorption performance of the composite foam. This comprehensive composite foam derived from WTRs has shown a promising development potential for using waste materials to relieve electromagnetic pollution.

8.
J Colloid Interface Sci ; 628(Pt B): 261-270, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35998452

RESUMO

Recently, high-performance functional composites for electromagnetic wave absorption (EWA) with tunable nano/micro-structures have attracted extensive attention. Herein, the flower-like electrically conductive and magnetic cobalt-nickel@carbon (CoNi@C) composites derived from bimetallic metal-organic frameworks (MOFs) were fabricated via solvothermal method and pyrolysis. By adjusting the ratios of different precursors, different morphological features of composites were formed. When the molar ratio of Co and Ni was 1:2, the CoNi@C composites exhibited the optimal minimum reflection loss (RLmin) of -56.89 dB at 6.7 GHz with an effective absorption bandwidth of 4.7 GHz, due to the coordinated dielectric and magnetic loss caused by the electromagnetic properties of each component as well as the interactions between the unique three-dimensional (3D) interfaces of flower-like structures that promoted the absorption and dissipation of composites for microwaves. The composites are expected to become promising candidates as high-efficiency absorbers in the electromagnetic protection field.

9.
Front Aging Neurosci ; 14: 913002, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35721013

RESUMO

Diabetes-associated cognitive decline (DACD), one of the complications of type 2 diabetes (T2DM), correlates significantly with the disorder in glycolipid metabolism, insulin/leptin resistance, and accumulation of ß-amyloid (Aß). Although gut microbiota transplantation (GMT), a novel non-invasive physiotherapy strategy, has been a promising intervention to alleviate the symptoms of T2DM, its protective effect on progressive cognitive decline remains elusive. Here, we transplanted the gut microbiota of healthy or cognitive decline donor rats into ZDF or LZ rats, and integrated microbiomics and metabolomics to evaluate the directional effect of the gut microbiota on the recipient rats. The basal metabolism phenotype changed in ZDF rats instead of in LZ rats. One possible mechanism is that the microbiota and metabolites alter the structure of the intestinal tract, stimulate the brain insulin and leptin signaling pathways, and regulate the deposition of Aß in the brain. It is worth noting that 10 species of genera, such as Parabacteroides, Blautia, and Lactobacillus, can regulate 20 kinds of metabolites, such as propanoic acid, acetic acid, and citramalic acid, and having a significant improvement on the cognitive behavior of ZDF rats. In addition, the correlation analysis indicated the gut microbiota and metabolites are highly associated with host phenotypes affected by GMT. In summary, our study indicates that altering the microbiota-gut-brain axis by reshaping the composition of gut microbiota is a viable strategy that has great potential for improving cognitive function and combatting DACD.

10.
Zhongguo Zhong Yao Za Zhi ; 47(4): 988-1000, 2022 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-35285199

RESUMO

This study explored the mechanism of Shenling Baizhu Powder(SLBZP) in the prevention and treatment of type 2 diabetes from the perspective of flora disorder and chronic inflammation. Fifty rats were randomly divided into normal control group, model control group, low-dose SLBZP group, medium-dose SLBZP group, and high-dose SLBZP group, with 10 rats in each group. The rats of 5 weeks old were administrated by gavage with ultrapure water and different doses of SLBZP decoction. The basic indicators such as body weight and blood glucose were monitored every week, and stool and intestinal contents were collected from the rats of 9 weeks old for 16 S rRNA sequencing and metabolomic analysis. An automatic biochemical analyzer was used to measure the serum biochemical indicators, ELISA to measure serum insulin, and chipsets to measure leptin and inflammatory cytokines. The results showed that SLBZP reduced the body weight as well as blood glucose, glycosylated hemoglobin, and lipid levels. In the rats of 9 weeks, the relative abundance of Anaerostipes, Turicibacter, Bilophila, Ochrobactrum, Acinetobacter, and Prevotella decreased significantly in the model control group, which can be increased in the high-dose SLBZP group; the relative abundance of Psychrobacter, Lactobacillus, Roseburia and Staphylococcus significantly increased in the model control group, which can be down-regulated in the high-dose SLBZP group. The differential metabolites of intestinal flora included 4-hydroxyphenylpyruvic acid, phenylpyruvic acid, octanoic acid, 3-indolepropionic acid, oxoglutaric acid, malonic acid, 3-methyl-2-oxovaleric acid, and methylmalonic acid. Moreover, SLBZP significantly lowered the levels of free insulin, insulin resistance and leptin resistance in rats. The variations in the serum levels of interleukin 1ß(IL-1ß) and monocyte chemoattractant protein-1(MCP-1) showed that SLBZP could alleviate chronic inflammation in rats. In conclusion, SLBZP can regulate intestinal flora and metabolites and relieve chronic inflammation to control obesity and prevent type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inflamação/tratamento farmacológico , Insulina , Pós , Ratos
11.
Am J Transl Res ; 11(9): 5338-5356, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632515

RESUMO

BACKGROUND: Colon cancer, or colorectal cancer (CRC), is a type of cancer that develops from large bowel. Previous data has demonstrated that microRNAs (miRNAs) may be involved in the formation and progression of CRC. The deregulation of miR-708 has been identified in multiple types of cancer. However, to the best of our knowledge, there are no data concerning the expression and role of miR-708 in CRC. METHODS: In this study, RT-PCR and Flow Cytometry were used to examine the expression and role of miR-708 and ZEB1 in proliferation and apoptosis. Transwell was used to examine the role of miR-708 and ZEB1 in invasion and migration. Western blot and qRT-PCR were conducted to determine the alteration of protein and miR-708 levels, respectively. RESULTS: MiR-708 was significantly downregulated in CRC tissues and cell lines. The restoration of the expression of miR-708 suppressed cell proliferation, induced apoptosis, and reduced metastasis in CRC in vitro. Additionally, bioinformatics analysis predicted ZEB1 as a novel target gene of miR-708. Furthermore, ZEB1 was upregulated in CRC, which was negatively correlated with miR-708 expression. Further studies showed that the overexpression of miR-708 and silence of ZEB1 inhibited stage of CRC via inhibiting AKT/mTOR signaling pathway in CRC cells. CONCLUSION: Taken together, these results indicate that miR-708 plays an important role in suppressing the development of CRC by directly targeting ZEB1 through AKT/mTOR signaling pathway, suggesting that miR-708 is a novel, effective therapeutic target for treating patients with CRC.

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