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This study demonstrates a differential absorption lidar (DIAL) for CO2 that integrates both single-photon direct detection and coherent detection. Based on all-fiber 1572â nm wavelength devices, this compact lidar achieves detection of CO2 concentration, wind field, and single photon aerosol backscattering signal. First, by comparing DIAL with VAISALA-GMP343, the concentration deviation between the two devices is less than 5â ppm, proving the accuracy of the DIAL. Second, through the scanning detection experiment in Chaohu Lake, Hefei, not only the CO2 concentration between single-photon detection and coherent detection but also the wind field was obtained, proving the multifunctionality and stability of the DIAL. Benefiting from the advantages of combined the two detection methods, single photon detection offers 3-km CO2 and aerosol backscattering signals; coherent detection offers a 360-m shorter blind zone and wind field. This DIAL can achieve monitoring of CO2 flux and sudden emissions, which can effectively compensate for the shortages of in-situ sensors and spaceborne systems.
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Correction for 'Mixing behavior of p-terphenyl-3,5,3',5'-tetracarboxylic acid with trimesic acid at the solid-liquid interface' by Wei Li et al., Phys. Chem. Chem. Phys., 2021, 23, 25896-25900, https://doi.org/10.1039/D1CP04770A.
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The molecular self-assembly of carboxylic acid molecules on a solid surface plays an important role in understanding the nanoscale-precision construction of functional patterns. In this study, the mixing behavior of p-terphenyl-3,5,3',5'-tetracarboxylic acid (TPTC) and trimesic acid (TMA) on a highly oriented pyrolytic graphite surface was studied by scanning tunneling microscopy (STM). The STM images show how the presence of a small percentage of TPTC molecules adsorbed onto TMA molecules can drastically change the on-surface self-assembly behavior of aromatic tetracarboxylic acid by initiating the nucleation and growth of a different polymorph. Molecular mechanics and density functional theory simulations of the adsorption energy and the additional stabilizing energy, induced by hydrogen bonds during assembly formations, provide insights into the relative stability of different assembled structures. Moreover, STM-based "nanoshaving" was conducted to confirm that the template layer underneath the second layer is indeed a random network.
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Carbon-based supercapacitors have shown great promise for miniaturized electronics and electric vehicles, but are usually limited by their low volumetric performance, which is largely due to the inefficient utilization of carbon pores in charge storage. Herein, we develop a reliable and scalable boric acid templating technique to prepare boron and oxygen co-modified highly-dense yet ultramicroporous carbons (BUMCs). The carbons are featured with high density (up to 1.62 g cm-3), large specific surface area (up to 1050 m2 g-1), narrow pore distribution (0.4-0.6 nm) and exquisite pore surface functionalities (mainly -BC2O, -BCO2, and -COH groups). Consequently, the carbons show exceptionally compact capacitive energy storage. The optimal BUMC-0.5 delivers an outstanding volumetric capacitance of 431 F cm-3 and a high-rate capability in 1 M H2SO4. In particular, an ever-reported high volumetric energy density of 32.6 Wh L-1 can be harvested in an aqueous symmetric supercapacitor. Our results demonstrate that the -BC2O and -BCO2 groups on the ultramicropore walls can facilitate the internal SO42- ion transport, thus leading to an unprecedented high utilization efficiency of ultramicropores for charge storage. This work provides a new paradigm for construction and utilization of dense and ultramicroporous carbons for compact energy storage.
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Background: While nanoplatform-based cancer theranostics have been researched and investigated for many years, enhancing antitumor efficacy and reducing toxic side effects is still an essential problem. Methods: We exploited nanoparticle coordination between ferric (Fe2+) ions and telomerase-targeting hairpin DNA structures to encapsulate doxorubicin (DOX) and fabricated Fe2+-DNA@DOX nanoparticles (BDDF NPs). This work studied the NIR fluorescence imaging and pharmacokinetic studies targeting the ability and biodistribution of BDDF NPs. In vitro and vivo studies investigated the nano formula's toxicity, imaging, and synergistic therapeutic effects. Results: The enhanced permeability and retention (EPR) effect and tumor targeting resulted in prolonged blood circulation times and high tumor accumulation. Significantly, BDDF NPs could reduce DOX-mediated cardiac toxicity by improving the antioxidation ability of cardiomyocytes based on the different telomerase activities and iron dependency in normal and tumor cells. The synergistic treatment efficacy is enhanced through Fe2+-mediated ferroptosis and the ß-catenin/p53 pathway and improved the tumor inhibition rate. Conclusion: Harpin DNA-based nanoplatforms demonstrated prolonged blood circulation, tumor drug accumulation via telomerase-targeting, and synergistic therapy to improve antitumor drug efficacy. Our work sheds new light on nanomaterials for future synergistic chemotherapy.
Assuntos
Doxorrubicina , Telomerase , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Doxorrubicina/administração & dosagem , Animais , Humanos , Telomerase/metabolismo , Linhagem Celular Tumoral , Camundongos , DNA/química , DNA/farmacocinética , DNA/administração & dosagem , Distribuição Tecidual , Nanopartículas/química , Neoplasias/tratamento farmacológico , Ferroptose/efeitos dos fármacos , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/administração & dosagem , Camundongos Endogâmicos BALB C , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinéticaRESUMO
Activin A plays an essential role in ischemic stroke as a well-known neuroprotective factor. We previously reported that Activin A could promote white matter remyelination. However, the exact molecular mechanism of Activin A in neuronal protection post-stroke is still unclear. In this study, the middle cerebral artery occlusion/reperfusion (MCAO/R)-induced ischemic stroke mouse model and oxygen-glucose deprivation/reoxygenation (OGD/R)-treated primary neurons were used to explore the molecular mechanism of Activin A-mediated neuroprotection against ischemic injuries. We found that Activin A significantly inhibits cGAS-STING-mediated excessive autophagy through the PI3K-PKB pathway, but not mTOR-dependent autophagy. Consequently, Activin A protected neurons against OGD/R-induced ischemic injury and improved cell survival in a dose-dependent manner. In addition, Activin A improved neurological functions and reduced infarct size of mice with MCAO/R-induced ischemic stroke by inhibiting autophagy. Furthermore, Activin A depended on ACVR1C receptor to exert neuroprotective effects in 1 h MCAO/R treated mice. Our findings showed that Activin A alleviated neuronal ischemic injury through inhibiting cGAS-STING-mediated excessive autophagy in mice with ischemic stroke, which may suggest a potential therapeutic target for ischemic stroke.