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1.
Adv Mater ; : e2405682, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38877752

ABSTRACT

Assembling ultrathin nanosheets into layered structure represents one promising way to fabricate high-performance nanocomposites. However, how to minimize the internal defects of the layered assemblies to fully exploit the intrinsic mechanical superiority of nanosheets remains challenging. Here, a dual-scale spatially confined strategy for the co-assembly of ultrathin nanosheets with different aspect ratios into a near-perfect layered structure is developed. Large-aspect-ratio (LAR) nanosheets are aligned due to the microscale confined space of a flat microfluidic channel, small-aspect-ratio (SAR) nanosheets are aligned due to the nanoscale confined space between adjacent LAR nanosheets. During this co-assembly process, SAR nanosheets can flatten LAR nanosheets, thus reducing wrinkles and pores of the assemblies. Benefiting from the precise alignment (orientation degree of 90.74%) of different-sized nanosheets, efficient stress transfer between nanosheets and interlayer matrix is achieved, resulting in layered nanocomposites with multiscale mechanical enhancement and superior fatigue durability (100 000 bending cycles). The proposed co-assembly strategy can be used to orderly integrate high-quality nanosheets with different sizes or diverse functions toward high-performance or multifunctional nanocomposites.

2.
J Am Chem Soc ; 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38865282

ABSTRACT

As the dimensionality of materials generally affects their characteristics, thin films composed of low-dimensional nanomaterials, such as nanowires (NWs) or nanoplates, are of great importance in modern engineering. Among various bottom-up film fabrication strategies, interfacial assembly of nanoscale building blocks holds great promise in constructing large-scale aligned thin films, leading to emergent or enhanced collective properties compared to individual building blocks. As for 1D nanostructures, the interfacial self-assembly causes the morphology orientation, effectively achieving anisotropic electrical, thermal, and optical conduction. However, issues such as defects between each nanoscale building block, crystal orientation, and homogeneity constrain the application of ordered films. The precise control of transdimensional synthesis and the formation mechanism from 1D to 2D are rarely reported. To meet this gap, we introduce an interfacial-assembly-induced interfacial synthesis strategy and successfully synthesize quasi-2D nanofilms via the oriented attachment of 1D NWs on the liquid interface. Theoretical sampling and simulation show that NWs on the liquid interface maintain their lowest interaction energy for the ordered crystal plane (110) orientation and then rearrange and attach to the quasi-2D nanofilm. This quasi-2D nanofilm shows enhanced electric conductivity and unique optical properties compared with its corresponding 1D geometry materials. Uncovering these growth pathways of the 1D-to-2D transition provides opportunities for future material design and synthesis at the interface.

3.
Angew Chem Int Ed Engl ; : e202408458, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38872327

ABSTRACT

Constructing structural materials from sustainable raw materials is considered an efficient way to reduce the potential threat posed by plastics. Nevertheless, challenges remain regarding combining excellent mechanical and thermal properties, especially the balance of strength and toughness. Here, we report a 3D nanofiber network interfacial design strategy to strengthen and toughen all-natural structural materials simultaneously. The introduced protonated chitosan at the interface between the surface oxidized 3D nanonetwork of bacterial cellulose forms the interfacial interlocking structure of nanonetworks, achieving a robust physical connection and providing enough physical contact sites for chemical crosslinking. The obtained sustainable structural material successfully integrates excellent mechanical and thermal properties on the nanoscale of cellulose nanofibers, such as light weight, high strength, and superior thermal expansion coefficient. The relationship between structural design and comprehensive mechanical property improvement is analyzed in detail, providing a universal perspective to design sustainable high-performance structural materials from nanoscale building blocks.

4.
J Gastrointest Oncol ; 15(2): 597-611, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38756631

ABSTRACT

Background: As one of the most common diseases in terms of cancer-related mortality worldwide, gastric adenocarcinoma (GA) frequently develops peritoneal metastases (PMs) in advanced stages. Systemic therapy or optimal supportive care are recommended for advanced GA; however, patients frequently develop drug resistance. Surgical resection is not recommended for stage IV patients, and there have been some controversies regarding the role of it in GA patients with PMs. The aim of the study was to preliminarily evaluate the possible effect of surgical treatments on patients with only PMs from GA. Methods: Data were collected from the Surveillance, Epidemiology and End Results (SEER) database (year 2000-2022). A propensity score matching (PSM) was performed to reduce the influence of selection bias and confounding variables on comparisons. Then Cox proportional hazard regression, Kaplan-Meier analysis, and log-rank test were performed to assess the efficacy of surgical treatment in patients with PMs from GA. Results: A total of 399 patients diagnosed with PMs from GA were enrolled for our analysis, of which, 180 (45.1%) patients did not receive surgery and 219 (54.9%) patients received surgery. Multivariate Cox regression analysis before PSM indicated higher rates of overall survival (OS) outcome for patients who had received surgery [hazard ratio (HR) =0.4342, 95% confidence interval (CI): 0.3283-0.5742, P<0.001]. After PSM, a total of 172 patients were enrolled, with 86 in each group. Multivariate Cox analysis showed that surgery was the independent factor reflecting patients' survival (HR =0.4382, 95% CI: 0.3037-0.6324, P<0.001). Subgroup survival analysis revealed that surgery may bring advantages to patients with grades I-IV, stages T1-T4, stage N0, and tumor size less than 71 mm (P<0.05). We also found that the OS of chemotherapy patients who had undergone surgery was better than that of chemotherapy patients who had not undergone surgery (P<0.01). Conclusions: Based on the SEER database, surgery has better OS for patients only with PMs from GA. Patients without lymph node metastasis and those who received chemotherapy before may benefit from surgery. These specific groups of patients may have surgery as an option to improve the prognosis.

5.
Small ; : e2401159, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38716681

ABSTRACT

Defects can introduce atomic structural modulation and tailor performance of materials. Herein, it demonstrates that semiconductor WO3 with inert electrocatalytic behavior can be activated through defect-induced tensile strains. Structural characterizations reveal that when simply treated in Ar/H2 atmosphere, oxygen vacancies will generate in WO3 and cause defective structures. Stacking faults are found in defects, thus modulating electronic structure and transforming electrocatalytic-inert WO3 into highly active electrocatalysts. Density functional theory (DFT) calculations are performed to calculate *H adsorption energies on various WOx surfaces, revealing the oxygen vacancy composition and strain predicted to optimize the catalytic activity of hydrogen evolution reaction (HER). Such defective tungsten oxides can be integrated into commercial proton exchange membrane (PEM) electrolyser with comparable performance toward Pt-based PEM. This work demonstrates defective metal oxides as promising non-noble metal catalysts for commercial PEM green-hydrogen generation.

6.
Adv Mater ; : e2402695, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38742820

ABSTRACT

Flexible supercapacitors can potentially power next-generation flexible electronics. However, the mechanical and electrochemical stability of flexible supercapacitors under different flexible conditions is limited by the weak bonding between adjacent layers, posing a significant hindrance to their practical applicability. Herein, based on the uninterrupted 3D network during the growth of bacterial cellulose (BC), a flexible all-in-one supercapacitor is cultivated through a continuous biosynthesis process. This strategy ensures the continuity of the 3D network of BC throughout the material, thereby forming a continuous electrode-separator-electrode structure. Benefitting from this bioinspired structure, the all-in-one supercapacitor not only achieves a high areal capacitance (3.79 F cm-2) of electrodes but also demonstrates the integration of high tensile strength (2.15 MPa), high shear strength (more than 54.6 kPa), and high bending resistance, indicating a novel pathway toward high-performance flexible power sources.

7.
Nat Commun ; 15(1): 3208, 2024 Apr 13.
Article in English | MEDLINE | ID: mdl-38615045

ABSTRACT

Investigations of one-dimensional segmented heteronanostructures (1D-SHs) have recently attracted much attention due to their potentials for applications resulting from their structure and synergistic effects between compositions and interfaces. Unfortunately, developing a simple, versatile and controlled synthetic method to fabricate 1D-SHs is still a challenge. Here we demonstrate a stress-induced axial ordering mechanism to describe the synthesis of 1D-SHs by a general under-stoichiometric reaction strategy. Using the continuum phase-field simulations, we elaborate a three-stage evolution process of the regular segment alternations. This strategy, accompanied by easy chemical post-transformations, enables to synthesize 25 1D-SHs, including 17 nanowire-nanowire and 8 nanowire-nanotube nanostructures with 13 elements (Ag, Te, Cu, Pt, Pb, Cd, Sb, Se, Bi, Rh, Ir, Ru, Zn) involved. This ordering evolution-driven synthesis will help to investigate the ordering reconstruction and potential applications of 1D-SHs.

8.
Sci Adv ; 10(14): eadl1884, 2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38579002

ABSTRACT

Introducing natural Bouligand structure into synthetics is expected to develop high-performance structural materials. Interfibrous interface is critical to load transfer, and mechanical functionality of bioinspired Bouligand structure yet receives little attention. Here, we propose one kind of hierarchical and reconfigurable interfibrous interface based on moderate orderliness to mechanically reinforce bioinspired Bouligand structure. The interface imparted by moderate alignment of adaptable networked nanofibers hierarchically includes nanofiber interlocking and hydrogen-bonding (HB) network bridging, being expected to facilitate load transfer and structural stability through dynamic adjustment in terms of nanofiber sliding and HB breaking-reforming. As one demonstration, the hierarchical and reconfigurable interfibrous interface is constructed based on moderate alignment of networked bacterial cellulose nanofibers. We show that the resultant bioinspired Bouligand structural material exhibits unusual strengthening and toughening mechanisms dominated by interface-microstructure multiscale coupling. The proposed interfibrous interface enabled by moderate orderliness would provide mechanical insight into the assembly of widely existing networked nanofiber building blocks toward high-performance macroscopic bioinspired structural assemblies.

9.
Small Methods ; 8(4): e2301487, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38651305
10.
Adv Mater ; 36(26): e2309770, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38447017

ABSTRACT

Percutaneous thermotherapy, a minimally invasive operational procedure, is employed in the ablation of deep tumor lesions by means of target-delivering heat. Conventional thermal ablation methods, such as radiofrequency or microwave ablation, to a certain extent, are subjected to extended ablation time as well as biosafety risks of unwanted overheating. Given its effectiveness and safety, percutaneous thermotherapy gains a fresh perspective, thanks to magnetic hyperthermia. In this respect, an injectable- and magnetic-hydrogel-construct-based thermal ablation agent is likely to be a candidate for the aforementioned clinical translation. Adopting a simple and environment-friendly strategy, a magnetic colloidal hydrogel injection is introduced by a binary system comprising super-paramagnetic Fe3O4 nanoparticles and gelatin nanoparticles. The colloidal hydrogel constructs, unlike conventional bulk hydrogel, can be easily extruded through a percutaneous needle and then self-heal in a reversible manner owing to the unique electrostatic cross-linking. The introduction of magnetic building blocks is exhibited with a rapid magnetothermal response to an alternating magnetic field. Such hydrogel injection is capable of generating heat without limitation of deep penetration. The materials achieve outstanding therapeutic results in mouse and rabbit models. These findings constitute a new class of locoregional interventional thermal therapies with minimal collateral damages.


Subject(s)
Carcinoma, Hepatocellular , Colloids , Hydrogels , Liver Neoplasms , Animals , Rabbits , Mice , Hydrogels/chemistry , Liver Neoplasms/therapy , Liver Neoplasms/pathology , Carcinoma, Hepatocellular/therapy , Carcinoma, Hepatocellular/pathology , Colloids/chemistry , Gelatin/chemistry , Humans , Magnetite Nanoparticles/chemistry , Magnetite Nanoparticles/therapeutic use , Hyperthermia, Induced/methods , Cell Line, Tumor , Injections , Magnetic Iron Oxide Nanoparticles/chemistry
11.
ACS Appl Mater Interfaces ; 16(10): 12865-12872, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38416689

ABSTRACT

The commercial capacitor using dielectric biaxially oriented polypropylene (BOPP) can work effectively only at low temperatures (less than 105 °C). Polyphenylene oxide (PPO), with better heat resistance and a higher dielectric constant, is promising for capacitors operating at elevated temperatures, but its charge-discharge efficiency (η) degrades greatly under high fields at 125 °C. Here, SiO2 layers are magnetron sputtered on both sides of the PPO film, forming a composite material of SiO2/PPO/SiO2. Due to the wide bandgap and high Young's modulus of SiO2, the breakdown strength (Eb) of this composite material reaches 552 MV/m at 125 °C (PPO: 534 MV/m), and the discharged energy density (Ue) under Eb improves to 3.5 J/cm3 (PPO: 2.5 J/cm3), with a significantly enhanced η of 89% (PPO: 70%). Furthermore, SiO2/PPO/SiO2 can discharge a Ue of 0.45 J/cm3 with an η of 97% at 125 °C under 200 MV/m (working condition in hybrid electric vehicles) for 20,000 cycles, and this value is higher than the energy density (∼0.39 J/cm3 under 200 MV/m) of BOPP at room temperature. Interestingly, the metalized SiO2/PPO/SiO2 film exhibits valuable self-healing behavior. These results make PPO-based dielectrics promising for high-temperature capacitor applications.

12.
Natl Sci Rev ; 11(3): nwad333, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38333231

ABSTRACT

Polysaccharide-based membranes with excellent mechanical properties are highly desired. However, severe mechanical deterioration under wet conditions limits their biomedical applications. Here, inspired by the structural heterogeneity of strong yet hydrated biological materials, we propose a strategy based on heterogeneous crosslink-and-hydration (HCH) of a molecule/nano dual-scale network to fabricate polysaccharide-based nanocomposites with robust wet mechanical properties. The heterogeneity lies in that the crosslink-and-hydration occurs in the molecule-network while the stress-bearing nanofiber-network remains unaffected. As one demonstration, a membrane assembled by bacterial cellulose nanofiber-network and Ca2+-crosslinked and hydrated sodium alginate molecule-network is designed. Studies show that the crosslinked-and-hydrated molecule-network restricts water invasion and boosts stress transfer of the nanofiber-network by serving as interfibrous bridge. Overall, the molecule-network makes the membrane hydrated and flexible; the nanofiber-network as stress-bearing component provides strength and toughness. The HCH dual-scale network featuring a cooperative effect stimulates the design of advanced biomaterials applied under wet conditions such as guided bone regeneration membranes.

13.
Adv Mater ; 36(23): e2313443, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38414173

ABSTRACT

Biological materials, although composed of meager minerals and biopolymers, often exhibit amazing mechanical properties far beyond their components due to hierarchically ordered structures. Understanding their structure-properties relationships and replicating them into artificial materials would boost the development of bulk structural nanocomposites. Layered microstructure widely exists in biological materials, serving as the fundamental structure in nanosheet-based nacres and nanofiber-based Bouligand tissues, and implying superior mechanical properties. High-efficient and scalable fabrication of bioinspired bulk structural nanocomposites with precise layered microstructure is therefore important yet remains difficult. Here, one straightforward bottom-up film-to-bulk assembly strategy is focused for fabricating bioinspired layered bulk structural nanocomposites. The bottom-up assembly strategy inherently offers a methodology for precise construction of bioinspired layered microstructure in bulk form, availability for fabrication of bioinspired bulk structural nanocomposites with large sizes and complex shapes, possibility for design of multiscale interfaces, feasibility for manipulation of diverse heterogeneities. Not limited to discussing what has been achieved by using the current bottom-up film-to-bulk assembly strategy, it is also envisioned how to promote such an assembly strategy to better benefit the development of bioinspired bulk structural nanocomposites. Compared to other assembly strategies, the highlighted strategy provides great opportunities for creating bioinspired bulk structural nanocomposites on demand.

14.
Nano Lett ; 24(3): 881-889, 2024 Jan 24.
Article in English | MEDLINE | ID: mdl-38198246

ABSTRACT

Cellulose nanofiber (CNF) possesses excellent intrinsic properties, and many CNF-based high-performance structural and functional materials have been developed recently. However, the coordination of the mechanical properties and functionality is still a considerable challenge. Here, a CNF-based structural material is developed by a bioinspired gradient structure design using hollow magnetite nanoparticles and the phosphorylation-modified CNF as building blocks, which simultaneously achieves a superior mechanical performance and electromagnetic wave absorption (EMA) ability. Benefiting from the gradient design, the flexural strength of the structural material reached ∼205 MPa. Meanwhile, gradient design improves impedance matching, contributing to the high EMA ability (-59.5 dB) and wide effective absorption width (5.20 GHz). Besides, a low coefficient of thermal expansion and stable storage modulus was demonstrated as the temperature changes. The excellent mechanical, thermal, and EMA performance exhibited great potential for application in stealth equipment and electromagnetic interference protecting electronic packaging materials.

15.
Adv Mater ; 36(7): e2306451, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37878793

ABSTRACT

All-natural materials derived from cellulose nanofibers (CNFs) are expected to be used to replace engineering plastics and have attracted much attention. However, the lack of crack extension resistance and 3D formability of nanofiber-based structural materials hinders their practical applications. Here, a multiscale interface engineering strategy is reported to construct high-performance cellulose-based materials. The sisal microfibers are surface treated to expose abundant active CNFs with positive charges, thereby enhancing their interfacial combination with the negatively charged CNFs. The robust multiscale dual network enables easy molding of multiscale cellulose-based structural materials into complex 3D special-shaped structures, resulting in nearly twofold and fivefold improvements in toughness and impact resistance compared with those of CNFs-based materials. Moreover, this multiscale interface engineering strategy endows cellulose-based structural materials with better comprehensive performance than petrochemical-based plastics and broadens cellulose's potential for lightweight applications as structural materials with lower environmental effects.

16.
Small ; 20(16): e2306914, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38041488

ABSTRACT

Electrocatalysts with high activity and durability for acidic oxygen evolution reaction (OER) play a crucial role in achieving cost-effective hydrogen production via proton exchange membrane water electrolysis. A novel electrocatalyst, Te-doped RuO2 (Te-RuO2) nanotubes, synthesized using a template-directed process, which significantly enhances the OER performance in acidic media is reported. The Te-RuO2 nanotubes exhibit remarkable OER activity in acidic media, requiring an overpotential of only 171 mV to achieve an anodic current density of 10 mA cm-2. Furthermore, they maintain stable chronopotentiometric performance under 10 mA cm-2 in acidic media for up to 50 h. Based on the experimental results and density functional calculations, this significant improvement in OER performance to the synergistic effect of large specific surface area and modulated electronic structure resulting from the doping of Te cations is attributed.

18.
BMC Neurosci ; 24(1): 64, 2023 12 08.
Article in English | MEDLINE | ID: mdl-38066457

ABSTRACT

BACKGROUND: Decreased eosinophil level is associated with poor outcomes after mechanical thrombectomy in patients with acute ischemic stroke (AIS), but the underlying mechanism of this association is elusive. We aimed to assess the mediation effect of symptomatic intracranial hemorrhage (sICH) on the aforementioned association. METHODS: A total of 328 consecutive AIS patients undergoing mechanical thrombectomy between May 2017 and March 2021 were analyzed. SICH was defined as any evidence of brain hemorrhage on CT scan with neurological deterioration. Regression analysis was used to assess the effect of eosinophils on sICH, and its effect on poor outcome. Mediation analysis was performed to assess the proportion of total effect by sICH on the association between eosinophils and poor outcome. RESULTS: Multivariate analysis revealed an independent association between eosinophil count and sICH after adjusting for potential confounders (odds ratio, 0.00; 95% CI, 0.00-0.01; P = 0.0141), which is consistent with the result of eosinophil count (dichotomous) as a categorical variable (odds ratio, 0.22; 95% CI, 0.11-0.46; P < 0.0001). Eosinophil count was negatively associated with poor outcome (odds ratio, 0.00; 95% CI, 0.00-0.02; P = 0.0021). Mediation analysis revealed that sICH partially mediated the negative relationship between eosinophil count and poor outcome (indirect effect=-0.1896; 95%CI: -0.3654 - -0.03, P < 0.001). CONCLUSION: This study showed an important effect of sICH on the association between eosinophils and poor outcome.


Subject(s)
Brain Ischemia , Ischemic Stroke , Stroke , Humans , Stroke/surgery , Eosinophils , Ischemic Stroke/complications , Brain Ischemia/surgery , Thrombectomy , Intracranial Hemorrhages/complications , Treatment Outcome , Retrospective Studies
19.
Sci Adv ; 9(43): eadi9944, 2023 Oct 27.
Article in English | MEDLINE | ID: mdl-37878702

ABSTRACT

Endowing three-dimensional (3D) displays with flexibility drives innovation in the next-generation wearable and smart electronic technology. Printing circularly polarized luminescence (CPL) materials on stretchable panels gives the chance to build desired flexible stereoscopic displays: CPL provides unusual optical rotation characteristics to achieve the considerable contrast ratio and wide viewing angle. However, the lack of printable, intense circularly polarized optical materials suitable for flexible processing hinders the implementation of flexible 3D devices. Here, we report a controllable and macroscopic production of printable CPL-active photonic paints using a designed confining helical co-assembly strategy, achieving a maximum luminescence dissymmetry factor (glum) value of 1.6. We print customized graphics and meter-long luminous coatings with these paints on a range of substates such as polypropylene, cotton fabric, and polyester fabric. We then demonstrate a flexible textile 3D display panel with two printed sets of pixel arrays based on the orthogonal CPL emission, which lays an efficient framework for future intelligent displays and clothing.

20.
Natl Sci Rev ; 10(11): nwad221, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37818118
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