Promoting copper catalysts with C60Ethylene glycol, a commodity chemical used as a feedstock and antifreeze agent, is synthesized industrially from dimethyl oxalate (DMO) by hydrogenation over ...precious-metal palladium catalysts at high pressures (typically 20 bars). Copper-chromium catalysts supported on silica as an alternative have required even high pressures. Zheng et al. show the addition of fullerene (C60) onto copper-silica allows DMO hydrogenation to be performed at ambient pressures with high yield (98%) and without deactivation after 1000 hours (see the Perspective by Gravel and Doris). The use of C60 to stabilize electron-deficient copper species that enhance hydrogen adsorption could likely be applied to other hydrogenation reactions catalyzed by copper. —PDS
Ultrasmall black phosphorus quantum dots (BPQDs) serve as the near‐infrared light absorber and charge transfer layer in the photocathode of a bifacial n‐type dye sensitized solar cell. Wideband light ...absorption and ≈20% enhancement in the light‐to‐electron efficiency are accomplished due to the fast carrier transfer and complementary light absorption by the BPQDs demonstrating that BP has large potential in photovoltaics.
Low-temperature photothermal therapy (PTT) systems constructed by integrating organic photothermal agents with other bactericidal components that initiate bacterial apoptosis at low hyperthermia ...possess a promising prospect. However, these multicomponent low-temperature PTT nanoplatforms have drawbacks in terms of the tedious construction process, suboptimal synergy effect of diverse antibacterial therapies, and high laser dose needed, compromising their biosafety in ocular bacterial infection treatment. Herein, a mild PTT nanotherapeutic platform is formulated via the self-assembly of a pH-responsive phenothiazinium dye. These organic nanoparticles with photothermal conversion efficiency up to 84.5% necessitate only an ultralow light dose of 36 J/cm2 to achieve efficient low-temperature photothermal bacterial inhibition at pH 5.5 under 650 nm laser irradiation. In addition, this intelligent mild photothermal nanoplatform undergoes negative to positive charge reversion in acid biofilms, exhibiting good penetration and highly efficient elimination of drug-resistant E. coli biofilms under photoirradiation. Further in vivo animal tests demonstrated efficient bacterial elimination and inflammatory mitigation as well as superior biocompatibility and biosafety of the photothermal nanoparticles in ocular bacterial infection treatment. Overall, this efficient single-component mild PTT system featuring simple construction processes holds great potential for wide application and clinical transformation.
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In this study, a novel bio-based environment-friendly membrane for oil-water separation is made via a facile method of coating agarose hydrogel on fabrics. The membrane can separate a ...range of different oil-water mixtures with >95% separation efficiency, indicating its high oil-water separation ability. Moreover, the membrane can be easily cleaned and maintain its high oil-water separation performance after 10 separation cycles. As the membrane is made of agarose hydrogel and fabrics, it is biocompatible and eco-friendly. Furthermore, since both the agarose and fabrics are commercially available, the facile preparation process can be scaled up for large-scale production of these oil-water separation membranes with low cost, which is of great benefit in solving the oily wastewater problem.
Adsorption plays a critical role in surface and interface processes. Fractional surface coverage and adsorption free energy are two essential parameters of molecular adsorption. However, although ...adsorption at the solid–gas interface has been well‐studied, and some adsorption models were proposed more than a century ago, challenges remain for the experimental investigation of molecular adsorption at the solid–liquid interface. Herein, we report the statistical and quantitative single‐molecule measurement of adsorption at the solid–liquid interface by using the single‐molecule break junction technique. The fractional surface coverage was extracted from the analysis of junction formation probability so that the adsorption free energy could be calculated by referring to the Langmuir isotherm. In the case of three prototypical molecules with terminal methylthio, pyridyl, and amino groups, the adsorption free energies were found to be 32.5, 33.9, and 28.3 kJ mol−1, respectively, which are consistent with DFT calculations.
Surface measurements with depth: A method for measuring adsorption free energy at the solid–liquid interface was developed on the basis of the inherent link between single‐molecule break junction measurements and the surface coverage of the molecule (see picture). The adsorption free energy measured for amino, methylthio, and pyridyl groups on a gold surface was found to agree quantitatively with theoretical results.
Breast cancer (BC) is one of the most common malignancies in women and the leading cause of cancer-related death in women. The newly emerged non-coding RNAs tsRNAs (tRNA-derived small RNAs) play an ...important role in the occurrence and development of BC. The purpose of this study was to comprehensively evaluate the prognostic, diagnostic and clinicopathological roles of tsRNAs in BC. Through literature screening, a total of 13 BC-related tsRNA studies were included in this meta-analysis, all of which passed quality assessment. Prognostic studies showed upregulated tsRNAs to be associated with poor survival outcomes (HR = 1.64, 95%CI 1.51-1.77) and downregulated tsRNAs to be associated with better outcomes (HR = 0.58, 95%CI 0.50-0.68). Results of diagnostic studies showed a combined sensitivity of 72% (95%CI 68-76%) and combined specificity of 64% (95%CI 61-67%); the AUC was 0.72 (95%CI 0.68-0.75) and the DOR 4.62 (95%CI 3.76-5.68). Finally, correlation analysis of clinicopathological features showed that downregulation of tsRNAs correlated significantly with age, TNM stage and lymphatic metastasis. Sensitivity analysis and publication bias showed no significant difference. In conclusion, BC-associated tsRNAs are closely related to the prognosis and clinicopathological features of patients with this disease and can be used to assist in early diagnosis of BC. Therefore, tsRNAs are potential targets for the diagnosis and treatment of BC.
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Thermal-initiation and photo-initiation are widely used for the preparation of hydrogels. But few studies were found to explore the difference between the hydrogel prepared by these ...two methods, especially the surface wettability. In this study, both methods were adopted for the synthesis of SNHM (SiMA-NVP-HEMA-MAA) silicone hydrogels. An interesting phenomenon was found that the surface of silicone hydrogels prepared by thermal polymerization was significantly more hydrophilic than the surface made by photo-initiation polymerization. Surface chemical groups on both hydrogels were characterized by attenuated total reflection Fourier transform infrared (ATR-FTIR) and the results showed no obvious difference. Furthermore, no significant distinction presented in the composition of the surface of the hydrogel either analyzed by X-ray photoelectron spectroscopy (XPS). However, atomic force microscope (AFM) images revealed difference, where the surface prepared by thermal polymerization was covered with nanoscale hills, while the surface by photo polymerization was supplied with a lot of nanoscale pits. The distinct wettabilities caused by different surface morphologies can be explained by Wenzel model and Cassie-Baxter model. This study concluded that the polymerization methods can lead to distinguish surface morphology, so as to surface wettabilities, which should be chosen thoughtfully in future studies.
The Medium‐Energy Electron Detector (MEED), a space weather monitoring instrument on the Fengyun‐3E (FY‐3E) satellite, is introduced in this paper. The MEED utilizes pin‐hole imaging technology on ...low‐orbit satellites for medium‐energy electron detection. Two orthogonal sensor heads enable the MEED to measure electrons from 18 directions simultaneously in the energy range of 30–600 keV (divided into eight exponentially distributed energy channels). The instrument has a ∼12° angular resolution and covers two 180° × 30° fields of view. With the magnetometer onboard the same satellite, the pitch angle distribution of medium‐energy electrons can be obtained with good angular resolution. This paper presents the design principle, ground calibration results, and preliminary on‐orbit test results of the FY‐3E MEED. The on‐orbit test results show that the medium‐energy electron fluxes, geographical distribution, energy spectrum, and pitch angle observed by the MEED are in agreement with the expected results. The MEED provides a new method to observe the low‐orbit energetic electron radiation environment from the FY‐3E satellite. Its successful in‐orbit operation will enable the theoretical study of radiation belts and improve space weather research.
Plain Language Summary
The Medium‐Energy Electron Detector (MEED) is a space weather monitoring instrument onboard the FY‐3E satellite. The MEED utilizes pin‐hole imaging technology on a low‐orbit satellite for medium‐energy electron detection for the first time. The MEED has two orthogonal sensor heads that can measure 30–600 keV electrons from 18 directions simultaneously. With the magnetometer onboard the same satellite, high‐resolution observations of the electron pitch angle distribution can be derived. The ground calibration and the preliminary in‐orbit measurements verify the good performance of the MEED. The MEED data will be of great importance for radiation belt research and space weather applications.
Key Points
The Medium‐Energy Electron Detector (MEED) on the FY3E satellite measures 30–600 keV electrons from 18 directions with two orthogonally‐mounted pin‐hole imaging sensor heads
The first results of the MEED are in agreement with the AE9 model and DEMETER observations
The high‐quality data of MEED will contribute to space physics and space weather research
Herein, a hetero(S,N)‐quintuple 9helicene (SNQ9H) molecule with an azacorannulene core was synthesized, currently representing the highest hetero‐helicene reported in the field of multiple ...nhelicenes. X‐ray crystallography indicated that SNQ9H includes not only a propeller‐shaped conformer SNQ9H‐1, but also an unforeseen quasi‐propeller‐shaped conformer SNQ9H‐2. Different conformers were observed for the first time in multiple n≥9helicenes, likely owing to the doping of heteroatomic sulfurs in the helical skeletons. Remarkably, the ratio of SNQ9H‐1 to SNQ9H‐2 can be regulated in situ by the reaction temperature. Experimental studies on the photophysical and redox properties of SNQ9H and theoretical calculations clearly demonstrated that the electronic structures of SNQ9H depend on their molecular conformations. The strategy of introducing heteroatomic sulfurs into the helical skeleton may be useful in constructing various conformers of higher multiple nhelicenes in the future.
Two conformers of a novel quintuple 9helicene with an azabuckybowl as the core were obtained by the deliberate introduction of sulfur heteroatoms into the helical skeleton. The structure–property relationship of different conformers was investigated through detailed experiment and theoretical calculations. The success of the sulfur‐doped strategy implies the potential of realizing higher multiple nhelicenes with various conformers.
Porcine circovirus type 2 (PCV2) exists widely in swine populations worldwide, and healthy PCV2 virus carriers have enhanced the severity of the infection, which is becoming more difficult to ...control. This study investigated the regulatory effect of Panax notoginseng saponins (PNS) on the oxidative stress and histone acetylation modification induced by PCV2 in vitro and in mice. In vitro, PNS significantly increased the scavenging capacities of superoxide anion radicals (O2•−) and hydroxyl radicals (•OH) and reduced the content of hydrogen peroxide (H2O2) induced by PCV2 in porcine alveolar macrophages (3D4/2). In addition, PNS decreased the protein expression level of histone H4 acetylation (Ac-H4) by increasing the activity of histone deacetylase (HDAC) in PCV2-infected 3D4/2 cells. In vivo, PNS enhanced the scavenging capacities of •OH and O2•− and reduced the content of H2O2 in the spleens of PCV2-infected mice. PNS also reduced the protein expression level of histone H3 acetylation (Ac-H3) by reducing the activity of histone acetylase (HAT) and increasing the activity of HDAC in the spleens of PCV2-infected mice. PCV2 infection activated oxidative stress and histone acetylation in vitro and in mice, but PNS ameliorated this oxidative stress. The research can provide experimental basis for exploring the antioxidant effect and the regulation of histone acetylation of PNS on PCV2-infected 3D4/2 cells and mice in vitro and in vivo, and provide new ideas for the treatment of PCV2 infection.
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