Neighboring sp-Hybridized Carbon Participated Molecular Oxygen Activation on the Interface of Sub-nanocluster CuO/Graphdiyne.

Activation of O2 is a crucial step in oxidation processes. Here, the concept of sp-hybridized C≡C triple bonds as an electron donor is adopted to develop highly active and stable catalysts for molecular oxygen activation. We demonstrate that the neighboring sp-hybridized C and Cu sites on the interface of the sub-nanocluster CuO/graphdiyne are the key structures to effectively modulate the O2 activation process in the bridging adsorption mode. The as-prepared sub-nanocluster CuO/graphdiyne catalyst exhibited the highest CO oxidation activity and readily converted 50% CO at around 133 °C, which is 34 and 94 °C lower than that for CuO/graphene and CuO/active carbon catalysts, respectively. In situ diffused reflectance infrared Fourier transform spectroscopy and density functional theory calculation results proved that the neighboring sp-hybridized C is more favorable to promote the rapid dissociation of carbonate than sp2-hybridized C without overcoming any energy barrier. The gaseous CO directly reacts with the active molecular oxygen and tends to proceed through the E-R mechanism with a relatively low energy barrier (0.20 eV). This work revealed that sp-hybridized C of graphdiyne-based materials could effectively improve the O2 activation efficiency, which could facilitate the low-temperature oxidation processes.

[Preparation and effect against cervical cancer invasion in vitro of harmine-loaded photosensitive liposomes].

Despite the development of HPV vaccines and screening programs, cervical cancer is still a serious threat to women's health. Early-stage cervical cancer is mainly treated by surgery. However, considering the serious complications after surgery, hyperthermia is recommended to enhance the effect of chemotherapy, retain the integrity of cervix, improve the treatment effect, which provides a therapeutic basis for the early treatment of cervical cancer. The photosensitive liposomes containing harmine and dye IR-780 were prepared by thin-film dispersion method and separated by Sephadex G-50 dextran gel column. The preparation conditions were optimized as the mass ratio of phospholipid to cholesterol membrane material being 8∶1 and that of drug to lipid being 1∶20. The results of HPLC showed that the encapsulation efficiency of harmine was 55.6%±0.18%. The prepared photosensitive liposomes were round and evenly distributed under transmission electron microscope, with the particle size of(125.2±0.62) nm determined by Marvin particle size analyzer and the Zeta potential of(-2.55±0.76) mV. Additionally, the photosensitive liposomes had the photothermal conversion efficiency, an important property of photothermal agent, of 27.1%±0.86%. The photosensitive liposomes stored at 4 ℃ showed stable encapsulation efficiency in the first 14 days without flocculation. The sulforhodamine B(SRB) assay was employed to determine the inhibitory effect of the liposomes on the proliferation of HeLa cells under near-infrared(NIR) irradiation or not, which showcased stronger inhibitory effect under NIR irradiation. The results of Transwell assay indicated that the prepared liposomes significantly inhibited the invasion and migration of HeLa cells in vitro. The findings of this study provide a basis for the treatment of cervical cancer with harmine.

Interfacial sp C-O-Mo Hybridization Originated High-Current Density Hydrogen Evolution.

High-current density (≥1 A cm-2) is a critical factor for large-scale industrial application of water-splitting electrocatalysts, especially seawater-splitting. However, it still remains a great challenge to reach high-current density due to the lack of active and stable intrinsic catalytic active sites in catalysts. Herein, we report an original three-dimensional self-supporting graphdiyne/molybdenum oxide (GDY/MoO3) material for efficient hydrogen evolution reaction via a rational design of "sp C-O-Mo hybridization" on the interface. The "sp C-O-Mo hybridization" creates new intrinsic catalytic active sites (nonoxygen vacancy sites) and increases the amount of active sites (eight times higher than pure MoO3). The "sp C-O-Mo hybridization" facilitates charge transfer and boosts the dissociation process of H2O molecules, leading to outstanding HER activity with high-current density (>1.2 A cm-2) in alkaline electrolyte and a decent activity and stability in natural seawater. Our results show that high-current density electrocatalysts can be achieved by interfacial chemical bond engineering, three-dimensional structure design, and hydrophilicity optimization.

Engineering the Nucleophilic Active Oxygen Species in CuTiOx for Efficient Low-Temperature Propene Combustion.

Industrialization has resulted in the rapid increase of volatile organic compound (VOC) emissions, which have caused serious issues to human health and the environment. In this study, an extensive Cu incorporating TiO2 induced nucleophilic oxygen structure was constructed in the CuTiOx catalyst, which exhibited superior low-temperature catalytic activity for C3H6 combustion. Thorough structural, surface characterization and density functional theory (DFT) calculations revealed that the Cu-O-Ti hybridization induced nucleophilic oxygen initiates C3H6 combustion by abstracting the C-H bond. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) results indicated that incorporated copper species acted as the major adsorbent site for the propene molecule. In combination of the DRIFTS and DFT results, the promotion effect of the nucleophilic O on the C-H bond abstraction and CO2 formation pathway was proposed. The surface doping induced nucleophilic oxygen as strong Brønsted basic sites for low-temperature propene combustion exemplified an efficient strategy for rational design of next-generation environmental catalysts.

Nanostructured MoO3 for Efficient Energy and Environmental Catalysis.

This paper mainly focuses on the application of nanostructured MoO3 materials in both energy and environmental catalysis fields. MoO3 has wide tunability in bandgap, a unique semiconducting structure, and multiple valence states. Due to the natural advantage, it can be used as a high-activity metal oxide catalyst, can serve as an excellent support material, and provide opportunities to replace noble metal catalysts, thus having broad application prospects in catalysis. Herein, we comprehensively summarize the crystal structure and properties of nanostructured MoO3 and highlight the recent significant research advancements in energy and environmental catalysis. Several current challenges and perspective research directions based on nanostructured MoO3 are also discussed.

Synthesis of 4-trifluoromethyl 2-pyrones and pyridones through the Brønsted base-catalyzed Pechmann-type reaction with cyclic 1,3-diones.

An efficient method for the synthesis of 4-trifluoromethyl 2-pyrones through the Brønsted base-catalyzed Pechmann-type reaction of cyclic 1,3-diones with ethyl 4,4,4-trifluoroacetoacetate is described. In the presence of 2-dimethylamino pyridine (2-DMAP) as a catalyst, the resulting 4-trifluoromethyl 2-pyrones are formed in good to excellent yields. Additionally, the reaction also provides 4-trifluoromethyl 2-pyridones by using the easily available NH4OAc as a source of NH3.

Dynamic Self-Assembly Adhesion of a Paraquat Droplet on a Pillar[5]arene Surface.

The adhesion of herbicide droplets on leaf surfaces plays an important role in the herbicide's adsorption by crops. How to control the adhesive binding which occurs through dynamic self-assembly between the macroscopic droplet and the surface is a challenging task. We introduce a host onto surfaces that controls the binding of guests in the paraquat droplets. The pillar[5]arene-functional surface showed the selective binding of paraquat droplets via the host-guest interaction. The work is promising for improving the efficiency of herbicides.

Cu2+ ion responsive solvent-free quantum dots.

Three quantum dots (QDs) nanofluids modified with different lengths of PEG chainsare synthesized, and the property-structure relationship of QDs nanofluids is established, to achieve QDs nanofluids with tunable fluidic or optical performance. Notably, the proposed QDs nanofluids demonstrate a selective response towards Cu(2+)-based on both fluorescence and contact angle.

A photoresponsive wettability switch based on a dimethylamino calix[4]arene.

A photoreversible switch based on a photoresponsive host-guest system consisting of dimethylamino calix[4]arene L and 4-(phenylazo)benzoic acid (O) is reported. The host L exhibited selective binding and release of O on UV and visible irradiation at 450 and 365 nm, respectively. Moreover, the photoresponsive host-guest complex was applied as a photocontrolled wettability switch on a functional micro/nanostructured silicon surface, and is thus promising for applications in sensors and microfluidic devices.

Application of the PBL Model Based on Deep Learning in Physical Education Classroom Integrating Production and Education.

This study aims to arouse students' interest in physical education (PE) in response to President Xi Jinping's call to strengthen students' physical quality because cultural courses occupy PE classes. Problem-based learning (PBL) is introduced, and a new teaching method of PE is proposed based on the convolutional neural network (CNN) in deep learning (DL). This method is employed to teach the experimental subjects in solid ball throwing. The students' interest, learning ability, and physical quality in the solid ball are investigated by a questionnaire survey. The questionnaire survey shows that the students' academic performance in solid ball throwing is improved, and their problem-solving ability, group cooperation ability, and theory learning ability are improved. Their time on a 1000-meter long run is shortened, and their body flexibility is improved. Therefore, it is believed that this new teaching method based on DL plays a significant role in improving students' physical quality.

Systems Pharmacology-Based Dissection of Anti-Cancer Mechanism of Traditional Chinese Herb Saussurea involucrata.

Cancer has the highest mortality in humans worldwide, and the development of effective drugs remains a key issue. Traditional Chinese medicine Saussurea involucrata (SI) exhibits a series of effects, such as anti-cancer, but the action mechanisms are still unclear. Here, systems pharmacology was applied to reveal its anti-cancer mechanism. First, we screened the active compounds of SI. Then, the compound-target network, target-disease network, and target-pathway network were constructed. DAVID was applied for GOBP analysis and KEGG pathway enrichment analysis on cancer-related targets. Seven potential compounds and 187 targets were identified. The target-disease classification network showed that compounds mainly regulated proteins related to cancer, nervous system diseases, and cardiovascular system diseases. Also, SI anti-tumor effect mainly associated with the regulation of NO production, angiogenesis, MAPK, and PKB from GOBP enrichment. Additionally, KEGG pathway enrichment indicated that targets involved in anti-inflammatory action, inhibiting angiogenesis and anti-proliferation or inducing apoptosis. Experimental validation showed that four active compounds could inhibit cell proliferation and promote apoptosis in A549 (except for kaempferol), PC-3, and C6 cells. This study not only provides experimental evidence for further research on SI in cancer treatment but also promotes the development of potential drugs of SI in modern medicine.

Transcriptome and Co-expression Network Analyses Reveal Differential Gene Expression and Pathways in Response to Severe Drought Stress in Peanut (Arachis hypogaea L.).

Drought is one of the major abiotic stress factors limiting peanut production. It causes the loss of pod yield during the pod formation stage. Here, one previously identified drought-tolerant cultivar, "L422" of peanut, was stressed by drought (35 ± 5%) at pod formation stage for 5, 7, and 9 days. To analyze the drought effects on peanut, we conducted physiological and transcriptome analysis in leaves under well-watered (CK1, CK2, and CK3) and drought-stress conditions (T1, T2, and T3). By transcriptome analysis, 3,586, 6,730, and 8,054 differentially expressed genes (DEGs) were identified in "L422" at 5 days (CK1 vs T1), 7 days (CK2 vs T2), and 9 days (CK3 vs T3) of drought stress, respectively, and 2,846 genes were common DEGs among the three-time points. Furthermore, the result of weighted gene co-expression network analysis (WGCNA) revealed one significant module that was closely correlated between drought stress and physiological data. A total of 1,313 significantly up-/down-regulated genes, including 61 transcription factors, were identified in the module at three-time points throughout the drought stress stage. Additionally, six vital metabolic pathways, namely, "MAPK signaling pathway-plant," "flavonoid biosynthesis," "starch and sucrose metabolism," "phenylpropanoid biosynthesis," "glutathione metabolism," and "plant hormone signal transduction" were enriched in "L422" under severe drought stress. Nine genes responding to drought tolerance were selected for quantitative real-time PCR (qRT-PCR) verification and the results agreed with transcriptional profile data, which reveals the reliability and accuracy of transcriptome data. Taken together, these findings could lead to a better understanding of drought tolerance and facilitate the breeding of drought-resistant peanut cultivars.

Elucidating the Nature of the Cu(I) Active Site in CuO/TiO2 for Excellent Low-Temperature CO Oxidation.

Stabilized Cu+ species have been widely considered as catalytic active sites in composite copper catalysts for catalytic reactions with industrial importance. However, few examples comprehensively explicated the origin of stabilized Cu+ in a low-cost and widely investigated CuO/TiO2 system. In this study, mass producible CuO/TiO2 catalysts with interface-stabilized Cu+ were prepared, which showed excellent low-temperature CO oxidation activity. A thorough characterization and theoretical calculations proved that the strong charge-transfer effect and Ti-O-Cu hybridization in Ti-doped CuO(111) at the CuO/TiO2 interface contributed to the formation and stabilization of Cu+ species. The CO molecule adsorbed on Cu+ and reacted directly with Ti doping-promoted active lattice oxygen via a Mars-van Krevelen mechanism, leading to the enhanced low-temperature activity.

[Effect of paidu baoshen pill in retarding the progression of chronic renal failure].

OBJECTIVE: To assess the impact of Paidu Baoshen Pill (PBP, modified Dahuang Zhechong Pill), in retarding the procession of chronic renal failure (CRF) of stage II-III. METHODS: The 283 patients of CRF stage II-III were randomly assigned to two groups, 151 patients in the treatment group treated with oral administration of PBP 3 g twice a day, and 132 patients in the control group with oxidative amylase aldehyde enveloped capsule 5-10 capsules thrice a day after meal. The course for both groups was 2 months, and the changes after 1 or 2 courses treatment in scoring of quality of life (QOL) and clinical symptoms, also in laboratory indexes including serum levels of creatinine (Cr), urea nitrogen (UN), and intrinsic creatinine clearance rate were observed. RESULTS: The total effective rate was 70. 86% (107/151 cases) in the treatment group and 44.70% (59/132 cases) in the control group, showing significant difference between them (X2 = 18.69, P < 0.01). Significant differences between groups were also shown in comparisons of scores of QOL and clinical symptoms after treatment. Inter-group comparison showed no difference in all the three indexes detected before treatment, but they did show statistical significance respectively after 1 and 2 courses of treatment (P < 0.05 and P < 0.01). CONCLUSION: PBP could effectively retard the progression of chronic renal failure and significantly improve the QOL of patients.

Molecular O2 Activation over Cu(I)-Mediated C≡N Bond for Low-Temperature CO Oxidation.

The activation of molecular oxygen (O2) is extremely crucial in heterogeneous oxidations for various industrial applications. Here, a charge-transfer complex CuTCNQ nanowire (CuTCNQ NW) array grown on the copper foam was first reported to show CO catalytic oxidation activity at a temperature below 200 °C with the activated O2 as an oxidant. The molecular O2 was energetically activated over the Cu(I)-mediated C≡N bond with a lower energy of -1.167 eV and preferentially reduced to •O2- through one-electron transfer during the activation process by density functional theory calculations and electron paramagnetic resonance. The theoretical calculations indicated that the CO molecule was oxidized by the activated O2 on the CuTCNQ NW surface via the Eley-Rideal mechanism, which had been further confirmed by in situ diffuse reflectance infrared Fourier transform spectra. These results indicated that the local C≡N bond electron-state engineering could effectively improve the molecular O2 activation efficiency, which facilitates the low-temperature CO catalytic oxidation. The findings reported here enhance our understanding on the molecular oxygen activation pathway over metal-organic nanocatalysts and provide a new avenue for rational design of novel low-cost, organic-based heterogeneous catalysts.

Coordinating Etk/Bmx activation and VEGF upregulation to promote cell survival and proliferation.

Etk/Bmx, a member of the Tec family of non-receptor tyrosine kinase, is characterized by an N-terminal PH domain and has recently been shown to be involved in the regulation of various cellular processes, including proliferation, differentiation, motility and apoptosis. Since VEGF and the activation of its signaling pathway have been implicated in modulating a variety of biological responses, we characterized the role of Etk-dependent signaling pathways involved in the upregulation of VEGF expression, and explored the functional implications of this enhancement in sustaining cell proliferation and survival. Using Northern and Western analyses, transient transfections, and pharmacological agents, we demonstrate that Etk activation alone is sufficient to transcriptionally induce VEGF expression, independent of the previously identified hypoxia response element (HRE), in both Pa-4 epithelial and TR-BBB endothelial cells under normoxia. In addition, Etk utilizes both MEK/ERK and PI3-K/Pak1 signaling pathways in concert to activate VEGF transcription. Functionally, Etk activation elicits a profound stimulatory effect on TR-BBB cell proliferation and formation of capillary-like networks in Matrigel containing reduced levels of growth factors. Finally, antisense oligonucleotides against either endogenous VEGF or Etk abrogate the proliferation of Etk-activated TR-BBB cells, and exogenous VEGF treatment stimulates endogenous Etk tyrosine phosphorylation in HUVECs. Taken together, these results indicate that VEGF is both an Etk downstream target gene and an Etk upstream activator, constituting a reciprocal Etk-VEGF autoregulatory loop. These findings, to our knowledge, are the first delineation of a network of positive feedforward signaling pathways that converge on the Etk-VEGF axis, causally associating Etk-mediation of VEGF induction with enhanced cellular processes in both epithelial and endothelial cells.

Electrospun polystyrene/graphene nanofiber film as a novel adsorbent of thin film microextraction for extraction of aldehydes in human exhaled breath condensates.

In the current study, we introduced a novel polystyrene/graphene (PS/G) composite nanofiber film for thin film microextraction (TFME) for the first time. The PS/G nanofiber film was fabricated on the surface of filter paper by a facile electrospinning method. The morphology and extraction performance of the resultant composite film were investigated systematically. The PS/G nanofiber film exhibited porous fibrous structure, large surface area and strong hydrophobicity. A new thin film microextraction-high performance liquid chromatography (TFME-HPLC) method was developed for the determination of six aldehydes in human exhaled breath condensates. The method showed high enrichment efficiency and fast analysis speed. Under the optimal conditions, the linear ranges of the analytes were in the range of 0.02-30 µmol L(-1) with correlation coefficients above 0.9938, and the recoveries were between 79.8% and 105.6% with the relative standard deviation values lower than 16.3% (n=5). The limits of quantification of six aldehydes ranged from 13.8 to 64.6 nmol L(-1). The established method was successfully applied for the quantification of aldehyde metabolites in exhaled breath condensates of lung cancer patients and healthy people. Taken together, the TFME-HPLC method provides a simple, rapid, sensitive, cost-effective, non-invasion approach for the analysis of linear aliphatic aldehydes in human exhaled breath condensates.

Cation-induced pesticide binding and release by a functionalized calix[4]arene molecular host.

Ion-controlled switchable progress is very important in many biological behaviors. Here, we reported K(+)-controlled switch, this switch system exhibited excellent carbaryl (G) binding/release by fluorescent (FL), ultraviolet-visible (UV) spectrums and (1)H NMR spectroscopy. More importantly, the K(+)-controlled G binding/release switch based on C4C5 not only in the solution, but also on the surface, promising for the application for the pesticide controlled release.

Fluorinated hyperbranched polyurethane electrospun nanofibrous membrane: fluorine-enriching surface and superhydrophobic state with high adhesion to water.

The fluorination of hyperbranched polyurethane (HPU) was achieved by atom transfer radical grafting polymerization (ATRgP) of dodecafluoroheptyl methacrylate that was initiated from 2-bromoisobutyryl bromide-modified end groups of HPU. The nanofibrous membrane of fluorinated HPU was prepared by electrospinning. The structure of fluorinated HPU was characterized by Fourier-transform infrared spectroscopy (FTIR) and (1)H nuclear magnetic resonance spectrum (1H NMR). The surface of nanofibrous membrane was investigated with scanning electron microscope (SEM), atomic force microscope (AFM), X-ray photoelectron spectroscopy (XPS) and water contact angle (WCA) analysis, respectively. The results suggested that compared with the reported linear fluorine-containing polyurethane materials, rather high fluorine content up to 29.14% was achieved on the surface of fluorinated HPU nanofibrous membrane. Meanwhile, a superhydrophobic surface (WCA 159.7°) with high adhesion to water was successfully fabricated via a convenient electrospinning process. The prepared material is promising for the application in microfluidic devices.

Protein adsorption and cell adhesion controlled by the surface chemistry of binary perfluoroalkyl/oligo(ethylene glycol) self-assembled monolayers.

This work reports a study of protein adsorption and cell adhesion on binary self-assembled monolayers (SAMs) of alkanethiols with terminal perfluoroalkyl (PFA) and oligo(ethylene glycol) (OEG) chains in varying ratios. The surface chemistry of the SAMs was characterized by contact angle measurement, grazing angle infrared spectroscopy (GIR), X-ray photoelectron spectroscopy, and the effect on protein adsorption was investigated by surface plasmon resonance, GIR, and immunosorbent assay. Hela cell adhesion on these surfaces was also studied by fluorescence microscopy. Results reveal that, compared to OEG, PFA tended to be a higher fraction of the composition in SAM than in the assembly solution. More interestingly, the nearly 38% PFA SAM had a strong antifouling property whereas the 74% PFA SAM showed a high adsorption capacity to protein and cell. The binary PFA/OEG SAMs were favorable for maintaining the fibrinogen conformation, hence its high activity. The findings may have important implications for constructing PFA-containing surfaces with the distinct properties that is highly resistant or highly favorable toward protein adsorption and cell adhesion.