Near-infrared light-responsive hydrogel actuator with complex deformations and remote precise control is fabricated from the natural bamboo. The resulting biomimetic bamboo/PNIPAM hydrogel actuator ...can be precisely designed to perform a variety of simulations.
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•Biomimetic actuators based on anisotropic natural bamboo were prepared.•Nigrosine was first used to fabricate light-responsive hydrogel actuator.•The actuator exhibits outstanding programmability and remote-control performance.•The actuator can move freely on the water surface based on Marangoni effect.
Near-infrared light-responsive hydrogels are one of the most important soft biomimetic actuators owing to their accuracy, remote control performance, and permeability. However, the complex deformations and materials of hydrogel actuators are still a serious challenge. Herein, we have developed a novel composite hydrogel actuator by combining natural bamboo sheet and nigrosine/poly(N-isopropylacrylamide) (PNIPAM) composite hydrogel. The high-efficient photothermal conversion of the nigrosine/PNIPAM composite hydrogel sheet generates light-responsive actuation that is remotely controllable. Furthermore, the bamboo sheet with fiber-oriented structure can be cut at different angles, which facilitates programmable 3D complex deformations in the actuator. Accordingly, we have designed a series of biomimetic actuating devices, including simulations of butterfly antenna, Dendrobium, smart switch, and even a multi-step deformational biomimetic claw. In addition, we also explored a biomimetic insect with precisely-controlled fast movements on the water surface based on Marangoni effect. This work provides a simple but general strategy for fabricating biomimetic actuators and will inspire new designs for intelligent soft actuators.
Colon adenocarcinoma (COAD) is one of the diseases with the highest morbidity and mortality in the world. At present, immunotherapy has become a valuable method for the treatment of COAD. Tumor ...mutational burden (TMB) is considered to be the most common biomarker for predicting immunotherapy. According to reports, the mutation rate of COAD ranks third. However, whether these gene mutations are related to TMB and immune response is still unknown. Here, COAD somatic mutation data were downloaded from The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) databases. Bioinformatics methods were used to study the relationships among gene mutations, COAD survival prognosis, and tumor immune response. A total of 22 of the top 40 mutations in TCGA and ICGC databases were the same. Among them, the
USH2A
mutation was associated with high TMB and poor clinical prognosis. According to Gene Set Enrichment Analysis (GSEA) and the CIBERSORT algorithm, we determined that the
USH2A
mutation upregulates signaling pathways involved in the immune system and the antitumor immune response. In cases with a
USH2A
mutation, the immune score and MSI score of TCGA samples increased, the expression of immune checkpoint genes decreased significantly, and the TIDE score decreased significantly. Dependent on the presence or absence of a
USH2A
mutation, TCGA COAD samples were analyzed for differentially expressed genes, 522 of which were identified. Using a univariate Cox analysis and LASSO COX analysis of these differential genes, a prediction model was established, which established significant differences in the infiltration of immune cells, immune checkpoint gene expression, immune score, MSI score, TMB, and TIDE in patients in high- and low-risk groups. In conclusion, mutation of
USH2A
is frequent in COAD and is related to an increase in TMB and the antitumor immunity. The differential genes screened by
USH2A
mutation allowed the construction of a risk model for predicting the survival and prognosis of cancer patients, in addition to providing new ideas for COAD immunotherapy.
•PPy-coated P(NIPAM-ABP) electrospun nanofiber can provide high strength.•PPy-coating by in situ polymerization can provide high light-responsive.•The actuator owns ultrafast deformation and rapid ...recovery.•The actuator can realize various 3D programmable complex deformations.•We have explored new biomimetic devices based on the advantages of the actuator.
Intelligent hydrogels are promising for biomimetic actuators, but acquiring actuations with both high speed and powerful force is still extremely difficult. Herein, a new robust polypyrrole (PPy)-coated copoly(isopropylacrylamide-4-benzoylphenyl acrylate) P(NIPAM-ABP) electrospun light-responsive hydrogel is explored. The (PPy)-coated P(NIPAM-ABP) hydrogel can be obtained via in-situ polymerization of pyrroles on the nanofiber-oriented electrospun P(NIPAM-ABP) hydrogel. Compared with original P(NIPAM-ABP) hydrogel, this PPy-coated P(NIPAM-ABP) hydrogel can integrate highly-enhanced mechanical strength (from 1.21 to 5.12 MPa of tensile strength) and ultrahigh-efficiency of photothermal conversion together. In addition, the orientation of P(NIPAM-ABP) nanofibers can still maintain well for programmable complex deformations. Consequently, the as-prepared robust bi-hydrogel actuator with ultrafast and complex deformations has been achieved, through bonding the PPy-P(NIPAM-ABP) hydrogel membrane with a polyethylene glycol diacrylate-cellulose nanofiber (PEGDA-CNF) composite hydrogel membrane via interfacial ultraviolet (UV) polymerization of PEGDA monomers. Several light-responsive biomimetic actuating devices have been achieved, which owning powerful force (can grab up 100 times of self-weight), rapid speed (1285.71°/s of folding) or precisely programmable complex deformations. Furthermore, two biomimetic devices with synergistic functions of the three advantages above have been explored, which can mimic the child’s sit-up and the starfish’s continuous crawling movement respectively. This work provides a robust remotely-controlled light-responsive hydrogel actuator with powerful force, ultrafast speed and programmable complex actuations, which will inspire the design and fabrication of novel soft biomimetic actuating materials and systems.
The design and synthesis of two semiconducting bis (4-ethynyl-bridging 1, 8-naphthalimide) bolaamphiphiles (BENI-COO
and BENI-NH
) to fabricate supramolecular metal-insulator-semiconductor (MIS) ...nanostructures for biomimetic hydrogen evolution under visible light irradiation is presented. A H
evolution rate of ca. 3.12 mmol g
⋅h
and an apparent quantum efficiency (AQE) of ca. 1.63 % at 400 nm were achieved over the BENI-COO
-NH
-Ni MIS photosystem prepared by electrostatic self-assembly of BENI-COO
with the opposite-charged DuBois-Ni catalysts. The hot electrons of photoexcited BENI-COO
nanofibers were tunneled to the molecular Ni collectors across a salt bridge and an alkyl region of 2.2-2.5 nm length at a rate of 6.10×10
s
, which is five times larger than the BENI-NH
nanoribbons (1.17×10
s
). The electric field benefited significantly the electron tunneling dynamics and compensated the charge-separated states insufficient in the BENI-COO
nanofibers.
The design and synthesis of two semiconducting bis (4‐ethynyl‐bridging 1, 8‐naphthalimide) bolaamphiphiles (BENI‐COO− and BENI‐NH3+) to fabricate supramolecular metal–insulator–semiconductor (MIS) ...nanostructures for biomimetic hydrogen evolution under visible light irradiation is presented. A H2 evolution rate of ca. 3.12 mmol g−1⋅h−1 and an apparent quantum efficiency (AQE) of ca. 1.63 % at 400 nm were achieved over the BENI‐COO−‐NH3+‐Ni MIS photosystem prepared by electrostatic self‐assembly of BENI‐COO− with the opposite‐charged DuBois‐Ni catalysts. The hot electrons of photoexcited BENI‐COO− nanofibers were tunneled to the molecular Ni collectors across a salt bridge and an alkyl region of 2.2–2.5 nm length at a rate of 6.10×108 s−1, which is five times larger than the BENI‐NH3+ nanoribbons (1.17×108 s−1). The electric field benefited significantly the electron tunneling dynamics and compensated the charge‐separated states insufficient in the BENI‐COO− nanofibers.
Two charged organic semiconductors based on naphthalimide bolaamphiphiles were designed to fabricate metal–insulator–semiconductor (MIS) photosystems with opposite‐charged DuBois nickel catalysts for biomimetic H2 evolution. The photoinduced charge carriers can be efficiently separated and tunneled to the Ni collectors across salt bridges and alkyl regions to reduce protons to H2, mediated by the intermolecular electrostatic field.
We report a facile approach which used common polymer materials to assemble a new type of B/N co-doped carbon materials through one-step carbonization from waterborne polyurethane (WPU), phenolic ...resin (PF) and graphene oxide (GO). During the process of synthetic WPU and WPU/PF/GO composite (WPGC), the nitrogen content was up-regulated by the addition large quantity of melamine. Moreover, nitrogen heteroatom had successfully added into the WPGC due to repetitive urethane bond (–NHCOO) from WPU as nitrogen-enriched carbon. Furthermore, the B–N bonds were decreased by ferric catalyst treatment and many micropores and small mesopores were formed from the boric acid and washing treatments. The WPGC/Fe/B as supercapacitor electrode exhibited a high specific capacitance of 340.5 F g
−1
at 0.5 A g
−1
, well rate performance, superior cycling stability, with the surface area, and pore volume (670.2 m
2
g
−1
and 0.3458 cm
3
g
−1
). More remarkably, since the WPGC/Fe/B electrode showed high capability, the fabricated symmetric supercapacitor exhibited a good power density (8.58 Wh kg
−1
at 492 W kg
−1
) and indicated outstanding cycle stability (90.56% capacitance retention after 5000 cycles at 5 A g
−1
) in 6 M KOH electrolyte. The work will develop a novel method to synthesize carbon-based electrode for applications in supercapacitors.
Unmanned aerial vehicles (UAVs) operating as airborne base stations (UAV-BSs) provide efficient on-demand services to ground users. UAV-BSs are inherently flexible and mobile, allowing them to be ...strategically deployed based on ground user distribution and quality of service requirements, including coverage rate, system lifecycle, and user fairness. Owing to the limited battery capacity and coverage range of the UAVs, managing them to extend their operational lifecycle, ensure service fairness, and maintain a specific real-time coverage rate is challenging. Therefore, a multi-objective optimization problem with constrained Pareto dominance is formulated. Subsequently, a novel assisted deep reinforcement learning model is developed to maximize the minimum remaining energy while simultaneously considering user fairness and coverage-rate requirements. The particle swarm optimization algorithm is adopted to assist multi-agent cooperative deep reinforcement learning. Finally, the simulation results show that the proposed model outperforms the other popular methods in terms of user fairness, system lifecycle, coverage rate, and energy efficiency in the context of multi-objective, multi-agent cooperative coverage control deployment.
Genome instability is a hallmark of cancer, and the function of lncRNAs in regulating genomic stability has been gradually characterized. However, the prognostic value of lncRNAs related to genetic ...instability has not been found in breast cancer. Here we constructed a genetic instability-related lncRNA model including U62317.4, SEMA3B-AS1, MAPT-AS1, AC115837.2, LINC01269, AL645608.7, and GACAT2. This model can evaluate the risk and predict the survival outcomes of patients. Further analysis showed that the differentially expressed genes between the high- and low-risk groups were enriched in immunity and cornified envelope formation pathways. In addition, M2 macrophages infiltrated more obviously in the high-risk group. In summary, lncRNAs related to genetic instability may influence the development of breast cancer through immune infiltration and keratinization. This study provides a wider insight into breast cancer development and treatment.
Dielectric elastomer (DE) actuators have been shown to have promising applications as soft electromechanical transducers in many emerging technologies. The DE actuators, which are capable of large ...actuation strain over a wide range of excitation frequencies, are highly desirable. Here, the first single‐component DE of a triblock copolymer with attractive electromechanical performance is reported. Symmetric poly(styrene‐b‐butyl acrylate‐b‐styrene) (SBAS) is designed and synthesized. The SBAS actuator exhibits about 100% static actuation area strain and excellent dynamic performance, as evidenced by a wide half bandwidth of 300 Hz and a very high specific power of 1.2 W g–1 within the excitation frequency range of 300–800 Hz.
Well‐designed polystyrene‐poly(n‐butyl acrylate)‐polystyrene triblock copolymer (SBAS) shows attractive electromechanical performance. Driven by an external electric field, the SBAS actuator shows about 100% static actuation area strain and excellent dynamic performance with a wide half bandwidth of 300 Hz and very high specific power of 1.2 W g–1 within the excitation frequency range 300–800 Hz.
Abstract
This study aims to investigate the hybrid effects of carbon nanotubes (CNTs) and steel fiber (SF) on dynamic mechanical behavior of ultra-high performance concrete (UHPC) under the ...high-speed dynamic loading effects. The functionalized CNTs content varied from 0.0% to 0.20%, and SF volume content was added from 0.5% to 2.0%. The UHPC specimens were tested at strain rates ranging from about 60 s-1 to 240 s-1 using the split Hopkinson pressure bar. The dynamic behavior of specimens was evaluated in terms of stress–strain relationships, energy absorption capacity and failure patterns. Test results show that dynamic compressive properties of UHPC are strongly sensitive to strain rates. The individual addition of CNTs obviously improves the dynamic performance of plain UHPC, and there exists an optimal CNTs content of about 0.10% to achieve better improvement effects. The dynamic increase factor (DIF) is almost unrelated to CNTs content but closely correlated to strain rate variations, which can be well described by a modified empirical formula. Furthermore, it is found that the hybrid CNTs and SF display more significant reinforcing effects on dynamic properties of UHPC, as the UHPC specimen with 0.10% CNTs and 2.0% SF exhibits the highest dynamic compressive strength and toughness. Meanwhile, UHPC reinforced by hybrid fibers is less sensitive to high strain rates compared to plain UHPC. From microscopic observations, it is reasonably believed CNTs and SF exert synergistic reinforcing effects on UHPC matrix in view of their respective characteristics, which are more significant in improving the interfacial transition zone (ITZ) structure between SF and the surrounding matrix. This work promotes a fundamental understanding for the reinforcing effects of CNTs on UHPC, and provides an effective strategy to reinforce UHPC from multiscale perspectives.
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