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1.
Zhongguo Zhen Jiu ; 44(7): 740-8, 2024 Jul 12.
Artigo em Chinês | MEDLINE | ID: mdl-38986585

RESUMO

OBJECTIVE: To observe the clinical effect of "brain-gut coherence" method of acupuncture on cerebral ischemic stroke (CIS) and explore its action mechanism. METHODS: A total of 82 patients with CIS were randomly divided into an observation group (41 cases, 3 cases dropped out, 2 cases discontinued) and a control group (41 cases, 4 cases dropped out, 2 cases excluded). The conventional basic treatment was administered in the two groups. Additionally, in the observation group, "brain-gut coherence" method of acupuncture was delivered. The stimulating points included the parietal and temporal anterior oblique line on the affected side, Zhongwan (CV 12), Guanyuan (CV 4), and bilateral Tianshu (ST 25), Zusanli (ST 36), Shangjuxu (ST 37) and Xiajuxu (ST 39). In the control group, the routine acupuncture was operated at Baihui (GV 20), Yintang (GV 24+), bilateral Fengchi (GB 20) and Zusanli (ST 36), and Hegu (LI 4), Jianyu (LI 15), Quchi (LI 11), Waiguan (TE 5), Futu (ST 32), Sanyinjiao (SP 6) and Taichong (LR 3) on the affected side. Acupuncture stimulation lasted 30 min each time, once daily, and for 5 days a week. The intervention for 4 weeks was required. The scores of Fugl-Meyer assessment scale (FMA), Berg balance scale (BBS) and the modified Barthel index (MBI), as well as the score of gastrointestinal symptoms were compared before and after treatment in the two groups. The neutrophil count (NUE) and the content of the serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) were detected before and after treatment in the two groups. Using 16S rRNA gene sequencing, the structure and relative abundance of intestinal microflora was detected before and after treatment; and with the enzyme linked immunosorbent assay (ELISA) adopted, the levels of intestinal fatty acid-binding protein (iFABP), D-lactate (D-LA), lipopolysaccharide (LPS), lipopolysaccharide binding protein (LBP), tumor necrosis factor-α(TNF-α), interleukin (IL)-1ß and IL-6 in the serum were detected before and after treatment in the two groups. RESULTS: After treatment, the scores of FMA, BBS and MBI were increased (P<0.05), and the scores of gastrointestinal symptoms were decreased (P<0.05) compared with those before treatment in the two groups. Compared with the control group, the scores of FMA, BBS and MBI were higher (P<0.05) and the score of gastrointestinal symptoms was lower (P<0.05) in the observation group after treatment. NEU and the content of serum NT-proBNP were reduced in the two groups (P<0.05), and the content of serum NT-proBNP in the observation group was lower than that of the control group (P<0.05) after treatment. Chao1, Ace, Sobs and Shannon indexes were increased after treatment compared with those before treatment in the two groups (P<0.05); and these indexes in the observation group were higher when compared with the control group (P<0.05). After treatment, the relative abundance of Bacteroidaceae, Enterobacteriaceae, Oscillospiraceae, Streptococcaceae and Sutterellaceae was reduced in comparison with that before treatment in the two groups (P<0.05); and the relative abundance of these microflora was lower in the observation group when compared with the control group (P<0.05). After treatment, the relative abundance of Lachnospiraceae, Ruminococcaceae, Bifidobacteriaceae and Coriobacteriaceae was increased in comparison with that before treatment in the two groups (P<0.05); and the relative abundance of these microflora was elevated in the observation group when compared with the control group (P<0.05). After treatment, the levels of iFABP, D-LA, LPS, LBP, TNF-α, IL-1ß and IL-6 were reduced when compared with those before treatment in the two groups (P<0.05), and these levels of the observation group were lower than those of the control group (P<0.05). CONCLUSION: "Brain-gut coherence" method of acupuncture can improve the motor function and gastrointestinal function of the patients with cerebral ischemic stroke, which may be related to modulating the structure of intestinal microflora, alleviating inflammatory reactions and accelerating the intestinal barrier repair.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Microbioma Gastrointestinal , AVC Isquêmico , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Idoso , AVC Isquêmico/terapia , AVC Isquêmico/fisiopatologia , Encéfalo/fisiopatologia , Adulto , Resultado do Tratamento , Atividade Motora , Interleucina-6/sangue , Fator de Necrose Tumoral alfa/sangue
2.
Polymers (Basel) ; 16(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-39000664

RESUMO

Developing biodegradable polyurethane (PU) materials as an alternative to non-degradable petroleum-based PU is a crucial and challenging task. This study utilized lactide as the starting material to synthesize polylactide polyols (PLA-OH). PLA-based polyurethanes (PLA-PUs) were successfully synthesized by introducing PLA-OH into the PU molecular chain. A higher content of PLA-OH in the soft segments resulted in a substantial improvement in the mechanical attributes of the PLA-PUs. This study found that the addition of PLA-OH content significantly improved the tensile stress of the PU from 5.35 MPa to 37.15 MPa and increased the maximum elongation to 820.8%. Additionally, the modulus and toughness of the resulting PLA-PU were also significantly improved with increasing PLA-OH content. Specifically, the PLA-PU with 40% PLA-OH exhibited a high modulus of 33.45 MPa and a toughness of 147.18 MJ m-3. PLA-PU films can be degraded to carbon dioxide and water after 6 months in the soil. This highlights the potential of synthesizing PLA-PU using biomass-renewable polylactide, which is important in green and sustainable chemistry.

3.
Nat Commun ; 15(1): 5632, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965276

RESUMO

The power conversion efficiency of perovskite solar cells continues to increase. However, defects in perovskite materials are detrimental to their carrier dynamics and structural stability, ultimately limiting the photovoltaic characteristics and stability of perovskite solar cells. Herein, we report that 6H polytype perovskite effectively engineers defects at the interface with cubic polytype FAPbI3, which facilitates radiative recombination and improves the stability of the polycrystalline film. We particularly show the detrimental effects of shallow-level defect that originates from the formation of the most dominant iodide vacancy (VI+) in FAPbI3. Furthermore, additional surface passivation on top of the hetero-polytypic perovskite film results in an ultra-long carrier lifetime exceeding 18 µs, affords power conversion efficiencies of 24.13% for perovskite solar cells, 21.92% (certified power conversion efficiency: 21.44%) for a module, and long-term stability. The hetero-polytypic perovskite configuration may be considered as close to the ideal polycrystalline structure in terms of charge carrier dynamics and stability.

4.
Nanoscale ; 16(25): 12248-12257, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38847572

RESUMO

The tensile brittleness of ceramic nanofibrous materials makes them unable to withstand the relatively large fracture strain, greatly limiting their applications in extreme environments such as high or ultra-low temperatures. Herein, highly stretchable and elastic ceramic nanofibrous membranes composed of titanium dioxide/silicon dioxide (TiO2/SiO2) bicomponent spiral crimped Janus fibers were designed and synthesized via conjugate electrospinning combined with calcination treatment. Owing to the opposite charges attached, the two fibers assembled side by side to form a Janus structure. Interestingly, radial shrinkage differences existed on the two sides of the TiO2/SiO2 composite nanofibers, constructing a helical crimp structure along the fiber axis. The special configuration effectively improves the stretchability of TiO2/SiO2 ceramic nanofibrous membranes, with up to 70.59% elongation at break, excellent resilience at 20% tensile strain and plastic deformation of only 3.48% after 100 cycles. Additionally, the relatively fluffy ceramic membranes constructed from spiral crimped Janus fibers delivered a lower thermal conductivity of 0.0317 W m-1 K-1, attributed to the increased internal still air content. This work not only reveals the attractive tensile mechanism of ceramic membranes arising from the highly curly nanofibers, but also proposes an effective strategy to make the ceramic materials withstand the complex dynamic strain in extreme temperature environments (from -196 °C to 1300 °C).

5.
Waste Manag ; 186: 55-63, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38861772

RESUMO

Metal smelting and combustion of solid fuels produce significant quantities of waste slag, leading to issues such as land occupation and environmental pollution. Understanding and controlling the microscale crystallization phenomena of these slags during thermal treatment is crucial for transforming waste slags into materials suitable for carbon capture or glass ceramics. Previous research has primarily focused on macroscopic crystallization behaviors, significantly advancing the utilization of waste slags in cement clinker production. However, macroscopic results are inadequate for precisely controlling the microscale crystallization behaviors of waste slags. Here, we employed the single hot thermocouple technique to visually explore crystal growth modes, shapes, sizes, numbers, and translational rates of the crystal growth front in a representative blast furnace slag under various isothermal temperatures. The results revealed that crystals exhibited five modes as the isothermal temperature gradually increased, including equiaxed, equiaxed & columnar, columnar, columnar & planar, and planar. Moreover, the translational rate of the crystal growth front increased from 0.011 µm·s-1 to 43.7 µm·s-1 with an increase in the isothermal temperature. Simultaneously, the number of crystals decreased from around 104 to 100 µm-2. On this basis, correlations between microscale crystallization behaviors and isothermal temperature were established to fill the current gap.


Assuntos
Cristalização , Gerenciamento de Resíduos/métodos , Resíduos Industriais/análise
6.
Adv Mater ; : e2406055, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829267

RESUMO

Elastic aerogels can dissipate aerodynamic forces and thermal stresses by reversible slipping or deforming to avoid sudden failure caused by stress concentration, making them the most promising candidates for thermal protection in aerospace applications. However, existing elastic aerogels face difficulties achieving reliable protection above 1500 °C in aerobic environments due to their poor thermomechanical stability and significantly increased thermal conductivity at elevated temperatures. Here, a multiphase sequence and multiscale structural engineering strategy is proposed to synthesize mullite-carbon hybrid nanofibrous aerogels. The heterogeneous symbiotic effect between components simultaneously inhibits ceramic crystalline coarsening and carbon thermal etching, thus ensuring the thermal stability of the nanofiber building blocks. Efficient load transfer and high interfacial thermal resistance at crystalline-amorphous phase boundaries on the microscopic scale, coupled with mesoscale lamellar cellular and locally closed-pore structures, achieve rapid stress dissipation and thermal energy attenuation in aerogels. This robust thermal protection material system is compatible with ultralight density (30 mg cm-3), reversible compression strain of 60%, extraordinary thermomechanical stability (up to 1600 °C in oxidative environments), and ultralow thermal conductivity (50.58 mW m-1 K-1 at 300 °C), offering new options and possibilities to cope with the harsh operating environments faced by space exploration.

7.
Adv Mater ; : e2401299, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38837520

RESUMO

Thermal insulation under extreme conditions requires the materials to be capable of withstanding complex thermo-mechanical stress, significant gradient temperature transition, and high-frequency thermal shock. The excellent structural and functional properties of ceramic aerogels make them attractive for thermal insulation. However, in extremely high-temperature environments (above 1500 °C), they typically exhibit limited insulation capacity and thermo-mechanical stability, which may lead to catastrophic accidents, and this problem is never effectively addressed. Here, a novel ceramic meta-aerogel constructed from a crosslinked nanofiber network using a reaction electrospinning strategy, which ensures excellent thermo-mechanical stability and superinsulation under extreme conditions, is designed. The ceramic meta-aerogel has an ultralow thermal conductivity of 0.027 W m-1 k-1, and the cold surface temperature is only 303 °C in a 1700 °C high-temperature environment. After undergoing a significant gradient temperature transition from liquid nitrogen to 1700 °C flame burning, the ceramic meta-aerogel can still withstand thousands of shears, flexures, compressions, and other complex forms of mechanical action without structural collapse. This work provides a new insight for developing ceramic aerogels that can be used for a long period in extremely high-temperature environments.

8.
Adv Mater ; : e2403223, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896500

RESUMO

Incorporating passive radiative cooling and heating into personal thermal management has attracted tremendous attention. However, most current thermal management materials are usually monofunctional with a narrow temperature regulation range, and lack breathability, softness, and stretchability, resulting in a poor wearer experience and limited application scenarios. Herein, a breathable dual-mode leather-like nanotextile (LNT) with asymmetrical wrinkle photonic microstructures and Janus wettability for highly efficient personal thermal management is developed via a one-step electrospinning technique. The LNT is synthesized by self-bonding a hydrophilic cooling layer with welding fiber networks onto a hydrophobic photothermal layer, constructing bilayer wrinkle structures that offer remarkable optical properties, a wetting gradient, and unique textures. The resultant LNT exhibits efficient cooling capacity (22.0 °C) and heating capacity (22.1 °C) under sunlight, expanding the thermal management zone (28.3 °C wider than typical textiles). Additionally, it possesses favorable breathability, softness, stretchability, and sweat-wicking capability. Actual wearing tests demonstrate that the LNT can provide a comfortable microenvironment for the human body (1.6-8.0 °C cooler and 1.0-7.1 °C warmer than typical textiles) in changing weather conditions. Such a wearable dual-mode LNT presents great potential for personal thermal comfort and opens up new possibilities for all-weather smart clothing.

9.
Heliyon ; 10(11): e31195, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38832279

RESUMO

Penthorum chinense Pursh (P. chinense), a functional food, has been applied to protect the liver against alcohol-related fatty liver disease (ALD) for a long history in China. This study was designed to evaluate the ameliorative activity of the polyphenolic fraction in P. chinense (PGF) depending on the relief of ALD. The ALD mouse model was established by exposing the mice to a Lieber-DeCarli alcohol liquid diet. We found that PGF administration significantly ameliorated alcohol-induced liver injury, steatosis, oxidative stress, and inflammation in mice. Furthermore, alcohol-increased levels of the critical hepatic lipid synthesis proteins sterol regulatory element binding transcription factor (SREBP-1) and diacylglycerol o-acyltransferase 2 (DGAT2) were attenuated by PGF. Similarly, PGF inhibited the expression of the lipid transport protein very low-density lipoprotein receptor (VLDLR). Interestingly, PGF restored alcohol-inhibited expression of carnitine palmitoyltransferase 1 (CPT1) and peroxisome proliferator-activated receptor alpha (PPARα), essential fatty acid ß-oxidation proteins. Mechanistic studies revealed that PGF protects against alcohol-induced hepatocyte injury and lipid deposition via the SIRT1/AMPK signaling pathway. In sum, this research clearly demonstrated the protective effects of PGF against ALD, which was mediated by activating SIRT1/AMPK pathways in hepatocytes. We provide a new theoretical basis for using P. chinense as a functional food in ALD.

10.
ACS Nano ; 18(26): 16895-16904, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38906832

RESUMO

Particulate matter (PM) pollution has posed a serious threat to public health, especially the global spread of infectious diseases. Most existing air filtration materials are still subjected to a compromise between removal efficiency and air permeability on account of their stacking bulk structures. Here, we proposed a self-polarized assembly technique to create two-dimensional piezoelectric nanofibrous webs (PNWs) directly from polymer solutions. The strategy involves droplets deforming into ultrathin liquid films by inertial flow, liquid films evolving into web-like architectures by instantaneous phase inversion, and enhanced dipole alignment by cluster electrostatics. The assembled continuous webs exhibit integrated structural superiorities of nanoscale diameters (∼20 nm) of the internal fibers and through pores (∼100 nm). Combined with the wind-driven electrostatic property derived from the enhanced piezoelectricity, the PNW filter shows high efficiency (99.48%) and low air resistance (34 Pa) against PM0.3 as well as high transparency (84%), superlight weight (0.7 g m-2), and long-term stable service life. This creation of such versatile nanomaterials may offer insight into the design and upgrading of high-performance filters.

11.
Adv Mater ; 36(28): e2310619, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38718249

RESUMO

The orthogonal structure of the widely used hole transporting material (HTM) 2,2',7,7'-tetrakis(N, N-di-p-methoxyphenylamino)-9,9'-spirobifluorene (Spiro-OMeTAD) imparts isotropic conductivity and excellent film-forming capability. However, inherently weak intra- and inter-molecular π-π interactions result in low intrinsic hole mobility. Herein, a novel HTM, termed FTPE-ST, with a twist conjugated dibenzo(g,p)chrysene core and coplanar 3,4-ethylenedioxythiophene (EDOT) as extended donor units, is designed to enhance π-π interactions, without compromising on solubility. The three-dimensional (3D) configuration provides the material multi-direction charge transport as well as excellent solubility even in 2-methylanisole, and its large conjugated backbone endows the HTM with a high hole mobility. Moreover, the sulfur donors in EDOT units coordinate with lead ions on the perovskite surface, leading to stronger interfacial interactions and the suppression of defects at the perovskite/HTM interface. As a result, perovskite solar cells (PSCs) employing FTPE-ST achieve a champion power conversion efficiency (PCE) of 25.21% with excellent long-time stability, one of the highest PCEs for non-spiro HTMs in n-i-p PSCs. In addition, the excellent film-forming capacity of the HTM enables the fabrication of FTPE-ST-based large-scale PSCs (1.0 cm2) and modules (29.0 cm2), which achieve PCEs of 24.21% (certificated 24.17%) and 21.27%, respectively.

12.
Chem Sci ; 15(17): 6488-6499, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38699260

RESUMO

In recent years, castration-resistant prostate cancer (CRPC) has profoundly impacted the lives of many men, and early diagnosis of medication and illness is crucial. Therefore, a highly efficient detection method for CRPC biomarkers and curing drugs is required. However, the complex and diverse structures of CRPC drugs pose significant challenges for their detection and differentiation. Lanthanide metal-organic frameworks (Ln-MOFs) show great potential for sensing applications due to their intense and characteristic luminescence. In this work, a series of new bimetallic Ln-MOFs (EuxTb1-x-MOF) based luminescent sensor arrays have been developed to identify CRPC drugs, including in mixtures, via principal component analysis (PCA) and hierarchical cluster analysis (HCA) methods. These Ln-MOFs are built with a highly conjugated H2L linker (H2L = 5-(4-(triazole-1-yl)phenyl)isophthalic acid) and exhibit robust strong luminescence emissions (mainly located at 543 and 614 nm) and high energy transfer efficiencies. More specifically, Eu0.096Tb0.904-MOF (MOF 3) has demonstrated good sensing performances for CRPC curing drugs in real human serum samples. Furthermore, the curing drug hydroxyflutamide has been combined with MOF 3, to construct a robust composite sensing platform MOF 3@hydroxyflutamide for highly efficient detection of CRPC biomarkers such as the androgen receptor (AR) and prostate-specific antigen (PSA). Finally, luminescence lifetime measurements, zeta potential measurements, and density functional theory (DFT) calculations were performed to gain insights into the sensing mechanism.

13.
ACS Nano ; 18(21): 13818-13828, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38748457

RESUMO

Ion transport efficiency, the key to determining the cycling stability and rate capability of all-solid-state lithium metal batteries (ASSLMBs), is constrained by ionic conductivity and Li+-migration ability across the multicomponent phases and interfaces in ASSLMBs. Here, we report a robust strategy for the large-scale fabrication of a practical solid electrolyte composite with high-throughput linear Li+-transport channels by compositing an all-trans block copolymer PVDF-b-PTFE matrix with ferroelectric BaTiO3-TiO2 nanofiber films. The electrolyte shows a sustainable electromechanical-coupled deformability that enables the rapid dissociation of anions with Li+ to create more movable Li+ ions and spontaneously transform the battery internal strain into Li+-ion migration kinetic energy. The ceramic framework homogenizes the interfacial potential with electrodes, endowing the electrolyte with a high conductivity of 0.782 mS·cm-1 and stable ion transport ability in ASSLMBs at room temperature. The batteries of LiFePO4/Li can stably cycle 1000 times at 0.5 C with a high capacity retention of 96.1%, and Ah-grade pouch or high-voltage Li(Ni0.8Mn0.1Co0.1)O2/Li batteries also exhibit excellent rate capability and cycling performance.

14.
ACS Nano ; 18(19): 12341-12354, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38695772

RESUMO

The patch with a superlubricated surface shows great potential for the prevention of postoperative adhesion during soft tissue repair. However, the existing patches suffer from the destruction of topography during superlubrication coating and lack of pro-healing capability. Herein, we demonstrate a facile and versatile strategy to develop a Janus nanofibrous patch (J-NFP) with antiadhesion and reactive oxygen species (ROS) scavenging functions. Specifically, sequential electrospinning is performed with initiators and CeO2 nanoparticles (CeNPs) embedded on the different sides, followed by subsurface-initiated atom transfer radical polymerization for grafting zwitterionic polymer brushes, introducing superlubricated skin on the surface of single nanofibers. The poly(sulfobetaine methacrylate) brush-grafted patch retains fibrous topography and shows a coefficient of friction of around 0.12, which is reduced by 77% compared with the pristine fibrous patch. Additionally, a significant reduction in protein, platelet, bacteria, and cell adhesion is observed. More importantly, the CeNPs-embedded patch enables ROS scavenging as well as inhibits pro-inflammatory cytokine secretion and promotes anti-inflammatory cytokine levels. Furthermore, the J-NFP can inhibit tissue adhesion and promote repair of both rat skin wounds and intrauterine injuries. The present strategy for developing the Janus patch exhibits enormous prospects for facilitating soft tissue repair.


Assuntos
Nanofibras , Animais , Ratos , Nanofibras/química , Cicatrização/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Pele/efeitos dos fármacos , Pele/patologia , Aderências Teciduais/prevenção & controle , Ratos Sprague-Dawley , Adesão Celular/efeitos dos fármacos , Cério/química , Cério/farmacologia , Propriedades de Superfície , Camundongos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia
15.
J Ethnopharmacol ; 330: 118227, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-38685364

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Androgenic alopecia (AGA) is the most prevalent form of hair loss in clinical practice and affects the physical and psychological well-being of adolescents. Paeonia lactiflora Pallas (PL), which is widely used in traditional Chinese medicine, enhances blood function and promotes hair growth, and ellagic acid (EA), a polyphenol in PL extract, shows strong antioxidant, anti-aging, and anti-inflammatory properties and also plays a role in the treatment of various skin conditions. However, its role and mechanism of action in AGA remain unclear. AIM OF THE STUDY: To determine whether EA can rescue slow hair regeneration by regulating dihydrotestosterone (DHT)-induced ferroptosis in AGA mice and clarify the effect of EA on DHT-induced ferroptosis in dermal papilla cells (DPCs). MATERIALS AND METHODS: Male C57BL/6 mice were used to establish a DHT-induced AGA mouse model, whereas DPCs were used to establish a DHT-induced cellular model. Thereafter, we investigated the therapeutic mechanism of action of EA via immunofluorescence, western blot analysis, immunohistochemistry, electron microscopy, and molecular docking. RESULTS: EA stimulated hair regeneration in mice and reversed DHT-induced increases in iron content, lipid peroxidation, and DHT-induced mitochondrial dysfunction by activating the Wnt/ß-catenin signaling pathway. Further, ß-catenin knockdown suppressed the inhibitory effect of EA on DHT-induced ferroptosis in DPCs. CONCLUSION: EA inhibits DHT-induced ferroptosis and promotes hair regrowth in mice by activating the Wnt/ß-catenin signaling pathway. Thus, it has potential for use as a treatment option for AGA.


Assuntos
Alopecia , Di-Hidrotestosterona , Ácido Elágico , Cabelo , Regeneração , Via de Sinalização Wnt , Animais , Masculino , Camundongos , Alopecia/tratamento farmacológico , Alopecia/induzido quimicamente , beta Catenina/metabolismo , Di-Hidrotestosterona/farmacologia , Ácido Elágico/farmacologia , Ferroptose/efeitos dos fármacos , Cabelo/efeitos dos fármacos , Cabelo/crescimento & desenvolvimento , Camundongos Endogâmicos C57BL , Regeneração/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos
16.
Polymers (Basel) ; 16(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38675079

RESUMO

Ever-increasing electromagnetic pollution largely affects human health, sensitive electronic equipment, and even military security, but current strategies used for developing functional attenuation materials cannot be achieved in a facile and cost-effective way. Here, a unique core-shell-like composite was successfully synthesized by a simple chemical approach and a rapid microwave-assisted carbonization process. The obtained composites show exceptional electromagnetic wave absorption (EMWA) properties, including a wide effective absorption band (EAB) of 4.64 GHz and a minimum reflection loss (RLmin) of -26 dB at 1.6 mm. The excellent performance can be attributed to the synergistic effects of conductive loss, dielectric loss, magnetic loss, and multiple reflection loss within the graphene-based core-shell-like composite. This work demonstrates a convenient, rapid, eco-friendly, and cost-effective method for synthesizing high-performance microwave absorption materials (MAMs).

17.
Adv Sci (Weinh) ; 11(21): e2309111, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38501909

RESUMO

Nickel oxide (NiOx)-based inverted perovskite solar cells stand as promising candidates for advancing perovskite photovoltaics towards commercialization, leveraging their remarkable stability, scalability, and cost-effectiveness. However, the interfacial redox reaction between high-valence Ni4+ and perovskite, alongside the facile conversion of iodide in perovskite into I2, significantly deteriorates the performance and reproducibility of NiOx-based perovskite photovoltaics. Here, potassium borohydride (KBH4) is introduced as a dual-action reductant, which effectively avoids the Ni4+/perovskite interface reaction and mitigates the iodide-to-I2 oxidation within perovskite film. This synergistic redox modulation significantly suppresses nonradiative recombination and increases the carrier lifetime. As a result, an impressive power conversion efficiency of 24.17% for NiOx-based perovskite solar cells is achieved, and a record efficiency of 20.2% for NiOx-based perovskite solar modules fabricated under ambient conditions. Notably, when evaluated using the ISOS-L-2 standard protocol, the module retains 94% of its initial efficiency after 2000 h of continuous illumination under maximum power point at 65 °C in ambient air.

18.
Adv Mater ; 36(25): e2313720, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38489784

RESUMO

The unsatisfactory properties of ceramic aerogels when subjected to thermal shock, such as strength degradation and structural collapse, render them unsuitable for use at large thermal gradients or prolonged exposure to extreme temperatures. Here, a building-envelope-inspired design for fabricating a thermomechanically robust all-fiber ceramic meta-aerogel with interlocked fibrous interfaces and an interwoven cellular structure in the orthogonal directions is presented, which is achieved through a two-stage physical and chemical process. Inspired by the reinforced concrete building envelope, a solid foundation composed of fibrous frames is constructed and enhanced through supramolecular in situ self-assembly to achieve high compressibility, retaining over 90% of maximum stress under a considerable compressive strain of 50% for 10 000 cycles, and showing temperature-invariance when compressed at 60% strain within the range of -100 to 500 °C. As a result of its distinct response to oscillation tolerance coupled with elastic recovery, the all-fiber ceramic meta-aerogel exhibits exceptional suitability for thermal shock resistance and infrared camouflage performance in cold (-196 °C) and hot (1300 °C) fields. This study provides an opportunity for developing ceramic aerogels for effective thermal management under extreme conditions.

19.
Nature ; 628(8007): 299-305, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38438066

RESUMO

Perovskite solar cells (PSCs) are among the most promising photovoltaic technologies owing to their exceptional optoelectronic properties1,2. However, the lower efficiency, poor stability and reproducibility issues of large-area PSCs compared with laboratory-scale PSCs are notable drawbacks that hinder their commercialization3. Here we report a synergistic dopant-additive combination strategy using methylammonium chloride (MACl) as the dopant and a Lewis-basic ionic-liquid additive, 1,3-bis(cyanomethyl)imidazolium chloride ([Bcmim]Cl). This strategy effectively inhibits the degradation of the perovskite precursor solution (PPS), suppresses the aggregation of MACl and results in phase-homogeneous and stable perovskite films with high crystallinity and fewer defects. This approach enabled the fabrication of perovskite solar modules (PSMs) that achieved a certified efficiency of 23.30% and ultimately stabilized at 22.97% over a 27.22-cm2 aperture area, marking the highest certified PSM performance. Furthermore, the PSMs showed long-term operational stability, maintaining 94.66% of the initial efficiency after 1,000 h under continuous one-sun illumination at room temperature. The interaction between [Bcmim]Cl and MACl was extensively studied to unravel the mechanism leading to an enhancement of device properties. Our approach holds substantial promise for bridging the benchtop-to-rooftop gap and advancing the production and commercialization of large-area perovskite photovoltaics.

20.
Angew Chem Int Ed Engl ; 63(18): e202320152, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38437457

RESUMO

Dopant-free hole transporting materials (HTMs) is significant to the stability of perovskite solar cells (PSCs). Here, we developed a novel star-shape arylamine HTM, termed Py-DB, with a pyrene core and carbon-carbon double bonds as the bridge units. Compared to the reference HTM (termed Py-C), the extension of the planar conjugation backbone endows Py-DB with typical intermolecular π-π stacking interactions and excellent solubility, resulting in improved hole mobility and film morphology. In addition, the lower HOMO energy level of the Py-DB HTM provides efficient hole extraction with reduced energy loss at the perovskite/HTM interface. Consequently, an impressive power conversion efficiency (PCE) of 24.33 % was achieved for dopant-free Py-DB-based PSCs, which is the highest PCE for dopant-free small molecular HTMs in n-i-p configured PSCs. The dopant-free Py-DB-based device also exhibits improved long-term stability, retaining over 90 % of its initial efficiency after 1000 h exposure to 25 % humidity at 60 °C. These findings provide valuable insights and approaches for the further development of dopant-free HTMs for efficient and reliable PSCs.

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