Construction of Zn-Cu bimetallic metal-organic frameworks for carbon dioxide capture.

Bimetallic metal-organic frameworks (MOFs) have shown more impressive performance in gas adsorption compared with monometallic MOFs. Herein, a Cu-Zn bimetallic metal-organic framework (Zn/Cu-BTC) was synthesized via a one-pot method, and its structure, thermal stability and CO2 adsorption property were investigated and compared with those of corresponding monometallic Cu-BTC and Zn-BTC. The results showed that Zn/Cu-BTC has a specific ortho-octahedral crystal morphology with a unique X-ray diffraction peak, the atomic ratio of Zn to Cu is about 1 : 5, and it remained stable at a temperature up to 490 K. In Zn/Cu-BTC, Cu2+ played a role in increasing the specific surface area and porosity of the MOF and improving the gas adsorption performance. The CO2 adsorption of Zn/Cu-BTC is lower than that of Cu-BTC but much higher than that of Zn-BTC, and CO2 adsorption heat was 30.52 kJ mol-1, which indicated physical adsorption. In addition, Zn/Cu-BTC had higher CO2/N2 adsorption selectivity compared with Zn-BTC and Cu-BTC, with a maximum value of 17. This study can be a reference for the research on improving the adsorption selectivity of gases by constructing bimetallic MOFs.

Preparation of convex edges in fused silica by single pass perforation with a 2D Airy-Gaussian beam.

Following ultrafast laser machining of fused silica, post-processing such as polishing and honing are typically required for edges. In this study, we employed a spatial light modulator (SLM) to generate the 2D Airy-Gaussian beam to prepare the convex edges in fused silica by using a single pass of a picosecond laser. It is found that, if the speed exceeds 5 mm/s, there would be plasma interference which is unfavorable for the separation process. A filament effect was observed when the internal laser peak power exceeds the damage threshold of fused silica. The shape of the convex edges was consistent with the propagation path of the 2D Airy-Gaussian beam inside the fused silica before separation. The inclination angle was 17° and 13°, respectively, on the upper and lower end of the edges. The results of this study provide a new, to our knowledge, method for the preparation of curved structures with different curvatures in transparent materials.

PUF60 promotes cell cycle and lung cancer progression by regulating alternative splicing of CDC25C.

Alternative splicing (AS) has been implicated in cell cycle regulation and cancer, but the underlying mechanisms are poorly understood. The poly(U)-binding splicing factor 60 (PUF60) is essential for embryonic development and is overexpressed in multiple types of cancer. Here, we report that PUF60 promotes mitotic cell cycle and lung cancer progression by controlling AS of the cell division cycle 25C (CDC25C). Systematic analysis of splicing factors deregulated in lung adenocarcinoma (LUAD) identifies that elevated copy number and expression of PUF60 correlate with poor prognosis. PUF60 depletion inhibits LUAD cell-cycle G2/M transition, cell proliferation, and tumor development. Mechanistically, PUF60 knockdown leads to exon skipping enriched in mitotic cell cycle genes, including CDC25C. Exon 3 skipping in the full-length CDC25C results in nonsense-mediated mRNA decay and a decrease of CDC25C protein, thereby inhibiting cell proliferation. This study establishes PUF60 as a cell cycle regulator and an oncogenic splicing factor in lung cancer.

Four-Dimensional Micro/Nanorobots via Laser Photochemical Synthesis towards the Molecular Scale.

Miniaturized four-dimensional (4D) micro/nanorobots denote a forerunning technique associated with interdisciplinary applications, such as in embeddable labs-on-chip, metamaterials, tissue engineering, cell manipulation, and tiny robotics. With emerging smart interactive materials, static micro/nanoscale architectures have upgraded to the fourth dimension, evincing time-dependent shape/property mutation. Molecular-level 4D robotics promises complex sensing, self-adaption, transformation, and responsiveness to stimuli for highly valued functionalities. To precisely control 4D behaviors, current-laser-induced photochemical additive manufacturing, such as digital light projection, stereolithography, and two-photon polymerization, is pursuing high-freeform shape-reconfigurable capacities and high-resolution spatiotemporal programming strategies, which challenge multi-field sciences while offering new opportunities. Herein, this review summarizes the recent development of micro/nano 4D laser photochemical manufacturing, incorporating active materials and shape-programming strategies to provide an envisioning of these miniaturized 4D micro/nanorobots. A comparison with other chemical/physical fabricated micro/nanorobots further explains the advantages and potential usage of laser-synthesized micro/nanorobots.

Monolayer heterojunction interactive hydrogels for high-freedom 4D shape reconfiguration by two-photon polymerization.

Mimicking natural botanical/zoological systems has revolutionarily inspired four-dimensional (4D) hydrogel robotics, interactive actuators/machines, automatic biomedical devices, and self-adaptive photonics. The controllable high-freedom shape reconfiguration holds the key to satisfying the ever-increasing demands. However, miniaturized biocompatible 4D hydrogels remain rigorously stifled due to current approach/material limits. In this research, we spatiotemporally program micro/nano (µ/n) hydrogels through a heterojunction geometric strategy in femtosecond laser direct writing (fsLDW). Polyethylene incorporated N-isopropylacrylamide as programmable interactive materials here. Dynamic chiral torsion, site-specific mutation, anisotropic deformation, selective structural coloration of hydrogel nanowire, and spontaneous self-repairing as reusable µ/n robotics were identified. Hydrogel-materialized monolayer nanowires operate as the most fundamental block at nanometric accuracy to promise high freedom reconfiguration and high force-to-weight ratio/bending curvature under tight topological control. Taking use of this biomimetic fsLDW, we spatiotemporally constructed several in/out-plane self-driven hydrogel grippers, diverse 2D-to-3D transforming from the same monolayer shape, responsive photonic crystal, and self-clenched fists at µ/n scale. Predictably, the geometry-modulable hydrogels would open new access to massively-reproducible robotics, actuators/sensors for microenvironments, or lab-on-chip devices.

High responsivity of VIS-NIR photodetector based on Ag2S/P3HT heterojunction.

Ag2S quantum dot (QD) photodetectors (PDs) have attracted a lot of attention in the field of imaging system and optical communication. However, the current Ag2S PDs mainly works in the near-infrared band, and its detection ability in the visible band remains to be strengthened. In this paper, we used poly(3-hexylthiophene) (P3HT) with high carrier mobility and Ag2S QDs to construct heterojunction PD. Stronger absorption in blends with polymer P3HT compared to single Ag2S QDs. The optical absorption spectra show that the Ag2S/P3HT has strong light absorption peak at 394 and 598 nm. The results show that P3HT significantly enhances the absorption of Ag2S QDs from the visible to near-infrared band. The output characteristics, transfer characteristics and fast switching capability of the device at 405 nm, 532 nm and 808 nm were tested. The device has the responsivity of 6.05 A W-1, 83.72 A W-1and 37.31 A W-1under 405 nm, 532 nm and 808 nm laser irradiation. This work plays an important role in improving the detection performance of Ag2S QDs and broadening its applications in photoelectric devices for weak light and wide spectrum detection.

RBM10 Loss Promotes EGFR-Driven Lung Cancer and Confers Sensitivity to Spliceosome Inhibition.

In lung adenocarcinoma (LUAD), loss-of-function mutations in the splicing factor RBM10 frequently co-occur with oncogenic EGFR mutations. A detailed understanding of the functional consequences and therapeutic impact of RBM10 loss in EGFR-mutant LUAD could help identify more effective treatment strategies. Here, analysis of LUAD data sets indicated that RBM10 mutations are mutually exclusive with mutations in the tumor suppressor gene TP53. In an EGFR-driven LUAD mouse model, lung-specific ablation of either Rbm10 or Trp53 similarly promoted tumor development, leading to overlapping gene expression changes enriched in cancer-related pathways. RBM10 loss induced key RNA splicing changes concordant in mice and LUAD patients. Importantly, RBM10 deficiency conferred high sensitivity to spliceosome inhibition in EGFR-mutated LUAD cells. Combined treatment with spliceosome inhibitor improved the therapeutic efficacy of EGFR tyrosine kinase inhibitor osimertinib and overcame drug resistance, especially in RBM10-deficient LUAD. Together, this study establishes RBM10 as a tumor suppressor akin to p53 and provides a therapeutic strategy of targeting the splicing machinery in EGFR-driven LUAD. SIGNIFICANCE: Loss of the splicing factor RBM10 is mutually exclusive with p53 mutations, promotes tumorigenesis, and enhances the efficacy of spliceosome inhibition in EGFR-driven lung cancer.

RNA splicing alterations in lung cancer pathogenesis and therapy.

RNA splicing alterations are widespread and play critical roles in cancer pathogenesis and therapy. Lung cancer is highly heterogeneous and causes the most cancer-related deaths worldwide. Large-scale multi-omics studies have not only characterized the mutational landscapes but also discovered a plethora of transcriptional and post-transcriptional changes in lung cancer. Such resources have greatly facilitated the development of new diagnostic markers and therapeutic options over the past two decades. Intriguingly, altered RNA splicing has emerged as an important molecular feature and therapeutic target of lung cancer. In this review, we provide a brief overview of splicing dysregulation in lung cancer and summarize the recent progress on key splicing events and splicing factors that contribute to lung cancer pathogenesis. Moreover, we describe the general strategies targeting splicing alterations in lung cancer and highlight the potential of combining splicing modulation with currently approved therapies to combat this deadly disease. This review provides new mechanistic and therapeutic insights into splicing dysregulation in cancer.

Sensitivity influencing factors during pesticide residue detection research via a terahertz metasensor.

Two metamaterial sensors were designed to test three pesticide residues. The influences of the metamaterial structure, the analyte composition and volume on the sensitivity have been studied. The metamaterial field-enhancement ability has an important influence on the sensitivity within the high-concentration range, while the coincidence between the metamaterial resonant frequency and the analyte fingerprint peak plays a dominant role within the low-concentration range. These findings allow us to better understand the process and find a way to improve the sensitivity.

Four-Dimensional Stimuli-Responsive Hydrogels Micro-Structured via Femtosecond Laser Additive Manufacturing.

Rapid fabricating and harnessing stimuli-responsive behaviors of microscale bio-compatible hydrogels are of great interest to the emerging micro-mechanics, drug delivery, artificial scaffolds, nano-robotics, and lab chips. Herein, we demonstrate a novel femtosecond laser additive manufacturing process with smart materials for soft interactive hydrogel micro-machines. Bio-compatible hyaluronic acid methacryloyl was polymerized with hydrophilic diacrylate into an absorbent hydrogel matrix under a tight topological control through a 532 nm green femtosecond laser beam. The proposed hetero-scanning strategy modifies the hierarchical polymeric degrees inside the hydrogel matrix, leading to a controllable surface tension mismatch. Strikingly, these programmable stimuli-responsive matrices mechanized hydrogels into robotic applications at the micro/nanoscale (<300 × 300 × 100 µm3). Reverse high-freedom shape mutations of diversified microstructures were created from simple initial shapes and identified without evident fatigue. We further confirmed the biocompatibility, cell adhesion, and tunable mechanics of the as-prepared hydrogels. Benefiting from the high-efficiency two-photon polymerization (TPP), nanometer feature size (<200 nm), and flexible digitalized modeling technique, many more micro/nanoscale hydrogel robots or machines have become obtainable in respect of future interdisciplinary applications.

Position-guided Fano resonance and amended GaussAmp model for the control of slow light in hybrid graphene-silicon metamaterials.

Position-guided Fano resonance is observed in hybrid graphene-silicon metamaterials. An outstanding application of such resonance is slow-light metadevices. The maximum group delay is 9.73 ps, which corresponds to a group delay in free-space propagation of 2.92 mm. We employ a coupled oscillator model to illustrate anomalous transmission, where the intensity of the Fano peak increases with the Fermi level. Furthermore, we amend the GaussAmp model to serve as a suitable control equation for the group delay. The coefficient of correlation (R2) is as high as 0.99998, while the lowest values of the root-mean-square error and sum of squared errors are respectively 0.00421 and 0.00156. These results indicate that the amended GaussAmp model accurately controls the trend of the group delay. This work not only clarifies the mechanism of Fano resonance generation but also provides a promising platform for dynamically adjustable optical switches and multidimensional information sensors.

Thermomechanical response of copper films irradiated by femtosecond-pulsed lasers with dynamic optical properties.

By taking into account the dynamic thermophysical and optical properties, the ultrafast thermoelastic response of thin copper film irradiated by femtosecond lasers has been researched. The temperature and stress fields of copper film irradiated by femtosecond lasers are analyzed in this work. The simulation results reveal that the degree of thermomechanical response is much underestimated, especially with higher laser fluence and smaller pulse duration. It is necessary to employ dynamic properties in ultrafast thermoelastic simulation for accuracy.

Theoretical study on femtosecond laser optical breakdown threshold in water mediated by aluminum nanoparticle coated with silica.

A strongly coupled finite element model of the optical breakdown during femtosecond laser pulse interaction, with different morphology of aluminum nanoparticles in water, was developed. This model provided new insight into the optical breakdown dependence on the nanoparticles' morphology and assembly. This model was used to theoretically investigate a 300 fs laser pulse interaction with uncoupled and plasmon coupled aluminum coated silica shell nanoparticles. This study revealed how the nanoparticles' one-dimensional assembly affected the optical breakdown threshold of its surrounding mediums. The optical breakdown threshold had much stronger dependence on the optical near-field enhancement than on the nanostructure's extinction cross-section. The maximum electric field that is outside of the aluminum nanoparticles, with 2 nm silica shell and 2 nm gap, was more than 4 times greater to the one inside of the aluminum nanoparticles. For dimer and trimer configuration, the calculated lattice cross-section temperatures at each breakdown threshold were below their melting point. It is suggested that water could be ionized by aluminum/silica (core/shell) nanostructure during femtosecond laser exposures without nanoparticles consumption. This model could increase understanding of the aluminum nanoparticle-mediated optical breakdown in water.

[Preparation of chitosan-encapsulated porous calcium polyphosphate bioceramic].

OBJECTIVE: To investigate the preparation of a chitosan-encapsulated porus calcium polyphosphate (CPP) bioceramic so as to provide a feasible approach to repair of the bone defect. METHODS: The chitosan microspheres were produced by chemical procedures. The CPP bioceramic was made by the following steps: annealing, ball milling, admixing, and calcinating. The chemical method was used to encapsule the calcinated bioceramic by the porus chitosan film. The physicochemical property, biomechanical property, and toxicity of the chitosan-encapsulated porus CPP bioceramic were analyzed. RESULTS: The uniform holes were observed in the CPP bioceramic under a microscope. The diameter of the hole was 100-300 microm. The chitosan microballoons were amber in color. The particles were uniform with a diameter of 200-400 microm, with a poor compressive strength. They could be easily ground by hand. The maximally tolerated dose of the CPP bioceramic leaching liquor given to the Jimpy mice of both sexes was >24 g/kg on average. The compressive strength reached 200 MPa, and the interval porosity was about 60%-80%, which could completely meet with the compressive strength of the bone substitute. CONCLUSION: The chitosan-encapsulated porous CPP bioceramic can be used as a good porous bioceramic scaffold material, which has a good biomechanical property with no acute toxicity, and so may be used as an excellent material for the bone substitute.