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Modifying separator with metal oxides has been considered as a strong strategy to inhibit the shuttling of soluble polysulfide in the lithium-sulfur battery (Li-S battery). Manganese dioxide (MnO2), one kind of transition metal oxide, is widely applied to decorate the PP (Polypropylene) separator. However, the fabrication by physical coating is always multistep and complicated. Here, we design a simple and fast method to chemically decorate separator. Based on the oxidizing property of acidic KMnO4 solution, the PP separator was oxidized and an ultrathin self-assembled MnO2 layer was directly constructed on one side of separator, by immersing in acidic KMnO4 solution for only 1 h. The self-assembled MnO2 layer has the synergistic effect of adsorption and catalytic conversion on polysulfides, which can effectively inhibit the shuttle effect. It can also help battery to maintain excellent electrochemical kinetics in the electrochemical cycle and maintain the effective recycling of active substances. As a result, the shuttling of polysulfide is greatly prohibited by this novel functional separator, and cycling stability is outstandingly improved, with a low-capacity decaying of 0.058% after 500 cycles at 0.5C. The rapid and simple modification method proposed in this study has a certain reference value for the future large-scale application of lithium-sulfur battery.

As a secondary Li-ion battery with high energy density, lithium-sulfur (Li-S) batteries possess high potential development prospects. One of the important ingredients to improve the safety and energy density in Li-S batteries is the solid-state electrolyte. However, the poor ionic conductivity largely limits its application for the commercial market. At present, the gel electrolyte prepared by combining the electrolyte or ionic liquid with the all-solid electrolyte is an effective method to solve the low ion conductivity of the solid electrolyte. We present a cross-linked gel polymer electrolyte with fluoroethylene carbonate (FEC) as a solid electrolyte interface (SEI) film formed for Li-S quasi-solid-state batteries, which can be simply synthesized without initiators. This gel polymer electrolyte with FEC as an additive (GPE@FEC) possesses high ionic conductivity (0.830 × 10-3 S/cm at 25 °C and 1.577 × 10-3 S/cm at 85 °C) and extremely high Li-ion transference number (tLi+ = 0.674). In addition, the strong ability toward anchoring polysulfides resulting in the high electrochemical performance of Li-S batteries was confirmed in GPE@FEC by the diffusion experiment, X-ray photoelectron spectroscopy analysis (XPS), and scanning electron microscopy (SEM) mapping of the S element. Such a high ion conductivity (IC) gel polymer electrolyte enables a competitive specific capacity of 940 mAh/g at 0.2C and supreme cycling performance for 180 cycles at 0.5C, which is far beyond that of conventional poly(ethylene oxide)-based quasi-solid-state Li-S batteries.

Li-rich Mn-based cathodes have attracted much attention due to their high capacity stemming from anion redox above 4.5 V. However, the continuous activation of Li2MnO3 in Li-rich Mn-based materials, which correlates with O2 release and TM migration, is usually unfavorable to structural stability. Herein, based on a gas-solid interface reaction, we tackle this continuous activation phenomenon by restricting the capacity release of Li2MnO3 via NH4HCO3 treatment in the Li1.2Ni0.36Mn0.44O2 cathode. After modification, oxygen vacancies associated with the spinel phase are introduced on the surface. The 4 mol % NH4HCO3-modified material's capacity starts at 182 mAh g-1 at 1 C instead of increasing from 173 to 186 mAh g-1 for 25 cycles in the pristine material. Meanwhile, it also exhibits an excellent capacity retention of 93.24% after 200 cycles (at 1 C), with a small voltage decay rate of 1.19 mV cycle-1.

Amplification pretargeting has the potential to increase the tracer's accumulation in the tumor. This study aimed to develop a three-step amplification pretargeting strategy in nuclear medicine with a polymer conjugated with multiple copies of peptide nuclear acid (PNA). In this study, the tracer 18 F-labeled complementary PNA (18 F-cPNA) was prepared by click-chemistry with high radiochemical purity (>99%) and great stability in vitro. The PAMMA dendrimer generation 4 (G4) was conjugated with multiple copies of PNAs. The average number of PNA groups in the G4-PNA conjugate was determined by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and the accessibility to the 18 F-cPNA was identified by size-exclusion high-performance liquid chromatography (SE-HPLC). There were approximately 11.7 of 64 carboxyl groups modified with PNAs, of which more than 99% were accessible to 18 F-cPNA. 18 F-cPNA was added to a mixture of CC49-cPNA and G4-PNA, and the complex exhibited a single peak on high-performance liquid chromatography (HPLC) as evidence of complete hybridization between 18 F-cPNA and CC49-cPNA/G4-PNA. The LS174T tumor cells were incubated with CC49-cPNA followed by G4-PNA as an amplification platform before 18 F-cPNA was added to hybridize with CC49-cPNA/G4-PNA. Compared with conventional pretargeting without G4-PNA, the radioactivity signal was amplified about four times, which demonstrated that the dendrimer-PNA conjugate plays a crucial role in signal amplification.

Soil salinisation is an important factor limiting the cultivation and distribution of Prunus mume. Therefore, identifying the regulation mechanism of salt tolerance of P. mume will promote its cultivation and molecular breeding. In this study, the garden tree species P. mume ‘Meiren’ was investigated, with a soil NaCl content (w/w) of 0.3%. Photosynthetic gas exchange parameters, relative electrical conductivity, malondialdehyde, osmoregulation substances, and antioxidant enzyme activity were measured in the early (3d), middle (10d), and late (30d) stages of stress. Salt treatment was applied for 0 h, 6 h, 24 h, and 72 h; following this, the gene library was constructed from the leaves. The results showed that the CBL-CIPK, mitogen-activated protein kinase, calcium-dependent protein kinase, and abscisic acid signalling pathways were involved in salt stress signal transduction of P. mume. Furthermore, bHLH, WRPK, ERF, and MYB were identified as potential key transcription factor families of salt tolerance in P. mume. Combined with determined physiological responses, the results showed that early salt stress inhibited the activities of RuBisCO, chlorophyll synthase, glutamyl tRNA reductase, divinyl reductase, and magnesium chelatase; resultantly, this led to a reduction in the photosynthetic rate. Also, it was found that P5CS, SS, LEA, and dehydrin regulated the synthesis of proline, soluble sugar, and macromolecular protein to alleviate osmotic stress. POD gene plays an important role in scavenging reactive oxygen species due to its regulation of POD activity. The findings of this research reveal the internal mechanism of the physiological response and provide a foundation for the construction of a genetic regulatory network in response to salt stress in P. mume.

The continuous growth of the solid-electrolyte interface (SEI) and material crushing are the fundamental issues that hinder the application of Ge anodes in lithium-ion batteries. Solving Ge deformation crushing during discharge/charge cycles is challenging using conventional carbon coating modification methods. Due to the chemical stability and high melting point of carbon (3500 °C), Ge/carbon hybridization at the atomic level is challenging. By selecting a suitable carbon source and introducing an active medium, we have achieved the Ge/carbon doping at the atom-level, and this Ge/carbon anode shows excellent electrochemical performance. The reversible capacity is maintained at 1127 mAh g-1 after 1000 cycles (2 A g-1 (2-71 cycles), 4 A g-1 (72-1000 cycles)) with a retention of 84 % compared to the second cycle. The thickness of the SEI is only 17.4 nm after 1000 cycles. The excellent electrochemical performance and stable SEI fully reflect the application potential of this material.

Binders have been confirmed to play a significant role in improving the cycling performance of Si anode. Some of natural biogum binders are exploited and related progresses are also achieved. However, the distinction of characteristics among different biogum binders as well as corresponding mechanisms and principles still remain to be elucidated. In this study, gum arabic (GA), guar gum (GG), and xanthan gum (XG) are selected for comparison. The highest initial Coulombic efficiency (ICE) of 90.4% is obtained with GA owing to diverse multiple interactions with Si nanoparticles to form a homogeneous covering that could protect Si core against being exposed to electrolyte and generating SEI film, as well as strong covalent network to suppress the isolation of Si, while plastic damage occurs during repeated volume change of Si because of irreversible bonding nature. By contrast, hydrogen bonding between polar –OH groups with self-healing nature provides Si anodes with GG and XG better cycling stability, while the optimized capacity of 1323 mAh g−1 after 100 cycles is retained with GG due to the extra ability to transfer Li+. This study provides the design and selection principles for binders applied in Si anodes of lithium-ion batteries.

A binder is an important component in lithium-ion batteries and plays a significant role in maintaining the properties of active substances. Most studies in the field of binders have only focussed on physical properties such as bonding performance. Here, a polyacrylic acid-modified binder was designed and adapted to Li[Ni0.8Co0.1Mn0.1]O2, which enhanced the electrochemical stability of Li[Ni0.8Co0.1Mn0.1]O2 from 30.2 to 66.6% (300 cycles at 1 C). We for the first time discovered that this was caused by a chemical reaction between polyacrylic acid and the residual lithium on the surface during the cycling, which formed a lithium propionic acid coating layer and maintained the stability of the layered structure.

Nickel-rich layered transition metal oxides are considered as promising cathode candidates to construct next-generation lithium-ion batteries to satisfy the demands of electrical vehicles, because of the high energy density, low cost, and environment friendliness. However, some problems related to rate capability, structure stability, and safety still hamper their commercial application. In this Review, beginning with the relationships between the physicochemical properties and electrochemical performance, the underlying mechanisms of the capacity/voltage fade and the unstable structure of Ni-rich cathodes are deeply analyzed. Furthermore, the recent research progress of Ni-rich oxide cathode materials through element doping, surface modification, and structure tuning are summarized. Finally, this review concludes by discussing new insights to expand the field of Ni-rich oxides and promote practical applications.

Phenyl-1,2-benzoselenazol-3(2H)-one (ebselen) is a classical mimic of glutathione peroxidase (GPx). Thioredoxin interaction endows ebselen attractive biological functions, such as antioxidation and anti-infection, as well as versatile therapeutic usage. Accordingly, application of ebselen analogues in biosensing, chemical labeling, imaging analysis, disease pathology, drug development, clinical treatment, etc. have been widely developed, in which mercaptans, reactive oxygen species, reactive sulfur species, peptides, and proteins were involved. Herein, focusing on the application of ebselen-agents in biochemistry, we have made a systematic summary and comprehensive review. First, we summarized both the classical and the innovative methods for preparing ebselen-agents to present the synthetic strategies. Then we discussed the full functional applicability of ebselen analogues in three fields of biochemical analysis including the fluorescence sensing and bioimaging, derivatization for high throughput fluorescence analysis, and the labeling gents for proteomics. Finally, we discussed the current challenges and perspectives for ebselen-agents as analytical tools in biological research. By presenting the multifunctional applicability of ebselen, we hope this review could appeal researchers to design the ebselen-related biomaterials for biochemical analysis.

Motivated by attributes including environmental hazards and resource value, the recycling of the spent graphite has aroused increasing attention. Meanwhile, a silicon/graphite composite has been considered as a promising high-capacity anode for lithium-ion batteries. However, uniform dispersion and outperformed stability of silicon (Si) particles in the graphite matrix still remain a great challenge. Current solutions mainly focus on the design of Si nanostructures and the overall architecture of the silicon/graphite composite, while little attention has been paid to the graphite matrix. Herein, the Si/spent graphite (Si/SG) composite was prepared based on the recycling of SG. The SG was in situ modified during the battery cycling process and formed unique physicochemical properties. By spontaneously tuning the zeta potential, the electrostatic force integrated the Si nanoparticles within the SG matrix to restrain the volume strain upon lithiation/delithiation. Besides, defect-enriched and exfoliated SG can effectively enhance the electric conductivity, facilitating the electrochemical kinetics in the electrodes. What is more, the oxygen-containing functional groups on the SG could adjust the solid electrolyte interphase (SEI) component by generating more organic components to improve the mechanical toughness of the SEI layer. Consequently, the Si/SG composite electrode delivers a high initial discharge capacity of 1321.8 mA h g−1 at 0.05 A g−1 and stable cycle life with a capacity retention of 69% at 1 A g−1 after 400 cycles. The proposed composite may provide some guidelines for improving the interface stability of the Si/graphite anode and simultaneously the high-value application of spent graphite.

Recycling and reusing spent graphite have become urgent tasks, with massive numbers of lithium-ion batteries (LIBs) from hybrid electric vehicles (HEVs)/electric vehicles (EVs) retired every year. Meanwhile, interlayer designs based on carbon materials have attracted widespread attention to suppress the polysulfide shuttle effect in high-energy-density lithium–sulfur (Li–S) batteries. Nevertheless, designing simple and low-cost carbon-derived interlayers still remains a great challenge. Spent graphite possesses a porous structure, defects, and polar functional groups that were formed in situ, which can significantly confine polysulfides through a combination of physical and chemical adsorption. Meanwhile, transition metals introduced due to the dissolution of cathode active materials can also anchor polysulfides via S–TM bonding, as well as improving electrical conductivity and boosting polysulfide conversion kinetics. Herein, spent graphite recycled from waste LIBs was employed for the first time as a functional interlayer for Li–S batteries based on its intrinsic properties. The spent-graphite-derived interlayer exhibited remarkably enhanced trapping and catalytic performance toward polysulfides. A high discharge capacity of 968 mA h g−1 with a low decay rate of 0.08% per cycle over 500 cycles at 1 C can be obtained. The present work not only provides a promising strategy for the design of interlayers, but it also shows a high-value application of spent graphite.

Sodium-ion batteries (SIBs) have shown promising prospects for complementarity to lithium-ion batteries (LIBs) in the field of grid-scale energy storage. After a decade of continuous fundamental research on SIBs, it's becoming increasingly urgent to advance the commercialization. For SIB anode materials, hard carbon is the most mature and currently the only material likely to be commercialized, but it is still far away from large-scale industrialization. Herein, we carry out a comprehensive overview of the current state of the art in terms of three main aspects. Firstly, a fundamental understanding of the microstructure and sodium storage mechanism of hard carbon is introduced, which can be categorized into three different processes: capacitive adsorption, nanopore filling, and intercalation in carbon interlayers. Then, based on an in-depth understanding of the sodium storage mechanism, optimization methods in terms of increasing the specific capacity, rate performance, initial coulombic efficiency (ICE), and long-cycling stability are comprehensively summarized and analyzed. Finally, potential methods and associated benefits for the design of carbon structures and the solid electrolyte interface (SEI) are discussed, hoping to provide useful guidelines for future research and commercialization.

Ni-rich lithium nickel cobalt aluminum oxide (NCA) cathodes, as one of the most promising candidates for the extended electric vehicle applications, have been widely recognized and attracted global...

Interactions between microorganisms and clay minerals influence the transport and cycling of metal contaminants in both marine and terrestrial environments. The present study was conducted to quantify the adsorption of dissolved cadmium, Cd(II), under seawater-like conditions to the marine cyanobacterium Synechococcus sp. PCC 7002, three common clay minerals (kaolinite, montmorillonite and illite), as well as cell-clay aggregates. We show here that the Synechococcus-only experiments removed the most Cd above pH 5.5, followed in decreasing order by aggregates of 50% cells:50% individual clays, aggregates of cells and all 3 clays, and individual clays. Electron microscope imaging showed that clays associated in a tangential edge-on orientation to the cells in Synechococcus-clay mineral aggregates. A non-electrostatic surface complexation modeling approach was used to fit Cd adsorption onto Synechococcus cells and individual clay minerals. The resulting Cd binding constants were then used in consort with surface functional group pKa values and site concentrations to accurately predict the extent of Cd adsorption onto the Synechococcus-clay mineral aggregates using the component additivity (CA) approach. We observed that the addition of cyanobacterial cells to clay mineral suspensions led to significantly larger mean aggregate sizes of clay minerals, enhancing the clay sedimentation rate. Although specifically focused on Cd, our study indicates that the ratio of bacterial plankton to clay minerals is an important determinant in terms of understanding the rate with which metals are transferred from the water column to the seafloor.

Energy storage devices are indispensable for supporting human activities; thus, producing sustainable environmental energy is a current focus of attention. Lithium–sulfur batteries (Li–S batteries)...

Au(I)-catalyzed selective reactions of Et- and tBu-substituted propiolates (1a and 1a′) with 1,2-benzisoxazole(2a) provide a new strategy for purposefully access to desired bioactive heterocycles. ...

Lithium-rich cathode oxides exhibit extraordinary specific capacities that are mainly ascribed to the accumulated redox reactions of anions and cations at high operating potentials. However, rapid ...

The Ni-rich cathodes are considered as the next generation candidate cathode material of lithium-ion batteries due to the high-energy–density and environmentally friendly. Unfortunately, the cathodes are up against severe structure instability at the repeated charge/discharge process, resulting in the attenuation of voltage and capacity. Herein, we proposed a novel strategy with uniform Al and Ti cations co-doping of LiNi0.8Co0.1Mn0.1O2 cathode. The modification strategy not only stabilizes the vulnerable layered structure but also mitigate voltage/capacity attenuation at different cutoff voltages. As a result, the modified cathode with trace content of Al and Ti cations co-doping can broaden the lithium ions diffusion channels, mitigate the structural collapse, and unfavorable phase transformation to some extent. Specifically, the modified sample exhibits remarkable enhanced electrochemical performance in discharge capacity and voltage retention of 76.75%, 98.78% at 1 C after 200 cycles. Even though at elevated voltage, the modified sample shows improved cycle life with a capacity retention of 70.93% after 200 cycles.

The increased application of layered oxide (LiCoO2) lithium ion batteries (LIBs) for electronic products will result in lots of spent layered cathodes in the near future. Furthermore, the explorati...

A palladium(II)-catalyzed direct 2-arylation of indoles by tetraarylstannanes with oxygen (balloon) as the oxidant at room temperature has been developed. Various tetraarylstannanes can be employed as aryl sources for 2-arylation of indoles in up to 89% yield, providing a practical and efficient catalytic protocol for accessing 2-arylindoles.

Purpose Long non-coding RNAs (lncRNAs) have been reported to be involved in a variety of cancers, including glioma. However, the exact role and underlying mechanism of lncRNA AGAP2 antisense RNA 1 (AGAP2-AS1) in glioma have not yet been fully elucidated. Methods The expression levels of AGAP2-AS1, microRNA-628-5p (miR-628-5p) and pleiotrophin (PTN) were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation, apoptosis, migration and invasion were detected by Cell Counting Kit-8 (CCK-8) assay, flow cytometry, transwell assay, respectively. Western blot assay was used to detect the protein level of PTN. The interaction between miR-628-5p and AGAP2-AS1 or PTN was predicted by bioinformatics software and confirmed by the dual-luciferase reporter and RNA Immunoprecipitation (RIP) assays. Murine xenograft model was established to confirm the role of AGAP2-AS1 in glioma progression in vivo. Results AGAP2-AS1 expression was upregulated in glioma tissues and cells. Knockdown of AGAP2-AS1 inhibited the proliferation, migration and invasion, but facilitated apoptosis in glioma cells. Moreover, AGAP2-AS1 could directly bind to miR-628-5p and its overexpression reversed the anti-tumor effect of miR-628-5p restoration on the progression of glioma cells. In addition, miR-628-5p directly targeted PTN and its inhibition abolished the inhibitory effect of PTN knockdown on the progression of glioma cells. Furthermore, AGAP2-AS1 functioned as a competing endogenous RNA (ceRNA) by sponging miR-628-5p to modulate PTN expression. Besides, AGAP2-AS1 depletion reduced tumor growth by upregulating miR-628-5p and downregulating PTN. Conclusion AGAP2-AS1 knockdown suppressed cell proliferation, migration and invasion but promoted cell apoptosis in glioma cells by regulating miR-628-5p/PTN axis, providing novel avenues for treatment of glioma.

Biological functions of chondroitin sulfate, including anti-oxidation and anti-inflammation, are associated with its molecular weight. This study aimed to evaluate the correlation between antioxidant activity and molecular weights of chondroitin sulfate derived from bovine nasal cartilage (BCS). BCS extracted by compound enzymatic method was further purified via DEAE-cellulose column separation to obtain BCS-II (129.4 kDa), which was further degraded by H2O2-Vc to obtain four subfractions: BCS-II-1 (92.7 kDa), BCS-II-2 (54.1 kDa), BCS-II-3 (26.3 kDa), and BCS-II-4 (19.7 kDa). Changes in the physicochemical properties of BCS-II before and after degradation were compared via FT-IR, NMR and monosaccharide composition analysis. Finally, antioxidant activities of BCS-II and its subfractions BCS-II-1–4 were compared. Our results showed that the H2O2-Vc system did not disrupt the primary functional group of BCS-II, with no significant change in sulfate content between BCS-II and its degraded fractions; however, uronic acid levels increased in degraded fractions when compared with BCS-II. In vitro, BCS-II-4 displayed the lowest molecular weight and had the strongest antioxidant activity. Therefore, the antioxidant activity of chondroitin sulfate in vitro is robustly associated with its molecular weight, and low-molecular-weight chondroitin sulfate can be used as an antioxidant in the food and pharmaceutical industries and other sectors.

Iridium-catalyzed oxidative o-alkenylation of benzylamines with acrylates was enabled by the directing group pentafluorobenzoyl (PFB). Density functional theory calculations were performed to explore the detailed reaction mechanism. The calculated results reveal that N-deprotonation prior to C–H activation is favored over direct C–H activation. Moreover, C–H activation is reversible and not the rate-determining step, which has been supported by the experimental observation. The regio- and stereoselectivity of ethyl acrylate insertion are controlled by the steric effect and the carbon atom with a larger orbital coefficient of the π* antibonding orbital in the nucleophilic attack, respectively. The migratory insertion of ethyl acrylate is computationally found to be rate-determining for the whole catalytic cycle. Finally, the seven-membered ring intermediate IM11 undergoes a sequential N-protonation and β-H elimination with the assistance of AcOH, rather than β-H elimination and reductive elimination proposed experimentally, to afford the o-alkenylated product. IM11 is unable to directly cyclize through C–N reductive elimination because both sp3-hybridized N and C atoms are unfavorable for N–C reductive elimination. The origin of the directing group PFB preventing the product and intermediates undergoing aza-Michael addition has been explained.

The Ni(0)-catalyzed coupling of benzimidazole with 1,1-disubstituted allenes represents a new strategy for achieving controllable C–H allylations, alkenylations and dienylations. To understand the detailed mechanisms and origins of the switchable selectivities, density functional theory (DFT) calculations were conducted. The results using a tBu-substituted allene demonstrate that the formation of the allylated product involves a Ni-catalyzed C–H activation mechanism through ligand-to-ligand-hydrogen transfer (LLHT) under base-free conditions. In contrast, a Ni/NaOtBu co-promoted C–H activation mechanism is newly proposed in the presence of NaOtBu, which is remarkably different from the previously reported literature. The novel mechanism emphasizes that NaOtBu abstracts the Ni-activated heterocyclic (ipso-C)H atom followed by turnover limiting Ni slippage, and subsequently the allylated product is generated after alkene insertion and protonation. The strong electrostatic attraction between Ni and heterocyclic ipso-C in the Ni slippage pre-intermediate is critical for facilitating the Ni slippage. Once formed, the allylated product, assisted by NaOtBu, further evolves into a more stable alkenylated isomer. Employing a (tert-butyldimethylsilyl)-ether substituted allene as the substrate, the NaOtBu-induced chemoselectivity for dienylation vs. alkenylation was also probed and it was found that the O(tBu)–H⋯O(Si) hydrogen bonding interaction in the C–O(Si) cleavage pre-intermediate remarkably weakens the adjacent C–O(Si) σ-bond, thereby resulting in an exclusive C–O(Si) cleaved dienylation product. Further theoretical predictions suggest that the chemoselectivity might be reversed by replacing tBu in NaOtBu by the withdrawing C(CF3)3 group.

Metal sulfides with high capacity have been considered as candidates for efficient sodium-ion storage. However, their undesirable rate capability and fast capacity fading hinder their commercial applications. Herein, we prepared a platelet-like CuS material with twin crystals. The edges of the platelet are composed of single crystal structures, and the interior of platelet contains twin crystal structures. Due to its structural and compositional advantages, this platelet-like CuS material with twin crystal structures manifests superior rate performance (420 mA h g−1 at 0.05 A g−1 and 277 mA h g−1 at 5 A g−1) and excellent cycling stability without capacity decay after around 500 cycles at 2 A g−1.

Background: DNA sensors are innate immune receptors that detect intracellular endogenous or exogenous DNA. They are critical to trigger immune response against DNA viral and intracellular bacterial infection, and are involved in inflammatory diseases and tumorigenesis. Recent accumulating evidences indicated that DNA sensors are also crucial for controlling the development of colorectal cancer (CRC). However, a systematic study on the expression profile of DNA sensors in CRC and their clinical significance are still lacking. Methods: We investigated the expression profile of DNA sensors in CRC and their clinical significance by taking advantage of clinical CRC samples, mouse AOM/DSS treatment model, and Oncomine ® bioinformatics platform. Results: Our study identified that the expression of DNA sensors, including AIM2, DAI, as well as inflammasome molecules ASC/IL-18, TLR9 and adaptor MyD88, and DDX60 decreased in human CRC, whereas the expression of DHX9, DHX36, and DDX41 significantly increased. Among them, the expression of AIM2/ASC/IL-18, MyD88, DAI, DHX36, and DDX60 were associated with cancer stages. In addition, we also performed correlation analysis between DNA sensors and their main signaling molecules to explore the possible mechanisms. The results showed that there were positive correlations between AIM2 and ASC/IL-18, DHX9 and MAVS, and TLR9 and MyD88 expression. In addition, the gene expression patterns of some DNA sensors were confirmed by Western-blot analysis. Conclusions: Our study revealed that the expression of multiple DNA sensors was deregulated in CRC and might be involved in tumor development. More importantly, the study identified that, among all these DNA sensors, AIM2, DAI, and DDX60 could be potentially critical for diagnosis, prognosis, and therapy of CRC and deserve further investigation.

In practice, high fidelity fluorescence imaging in vivo faces many issues, for example: (1) the fluorescence background of the probe is bleached by the wide intensity scale of fluorescence microscopy, displaying an inherent false negative background (FNB); and (2) the dosage of the probe has to be increased to achieve sufficient intensity for in vivo imaging, causing a vicious cycle that exacerbates the FNB. Herein, we constructed a fluorophore (F)–electron donor (D)–electron regulator (R) system, and thereby developed a dual modulation strategy for the de novo design of high fidelity probes. Using cross-talk modulation, the probe allows: (1) enhanced ESET (excited state electron transfer) from F to D, which minimizes the inherent FNB based on synergistic PET (photo induced electron transfer); and (2) the inhibition of PET and weakening of ESET from F to D to maximize the reporting intensity to further reduce the FNB, which is additionally enhanced by an overdose of the probe. To test the implementation, we constructed a 7-hydroxy-2-oxo-2H-chromene-3-carbaldehyde (HPC) series of probes, with HPC (F) as the fluorophore, 2-hydrazinylpyridine, which was screened as an electronically adjustable donor (D), and electronic regulators (R). In particular, HPC-7 and HPC-8 provided cell/zebrafish imaging with negligible background even using the rather low fluorescence scale of microscopy (a region for revealing hidden background). Interestingly, with the specificity of HPC for reporting zinc, we achieved probe HPC-5, which possesses both an ultralow inherent FNB and optimal reporting intensity for tissue and in vivo imaging, enabling the in vivo imaging of zinc in mice for the first time. Under this high-fidelity mode, the fluorescence monitoring of zinc ions during the development of liver cancer in mice was successfully performed. We envision that the dual modulation strategy with the F–D–R system could provide a useful concept for the de novo design of practical probes., We engineered a cross-talk electron transfer strategy using an F–D–A system to reduce the false negative background for high fidelity imaging in vivo.

In order to determine trace impurities in the nuclear grade UF4, an analysis method based on the standard addition and 103Rh internal standardization techniques combined with ICP-MS has been established. The examination tests, including comparison with the quantity of trace impurities assigned in a certified reference uranium oxide and determination of the standard addition recovery, were performed to validate the accuracy and precision of the method. Total 42 trace impurity elements from Li to Bi were determined, with the method detection limit for the 42 impurities were found in the range of 0.0004–0.072 μg g−1. The recoveries were varied from 92% to 111%, and the relative deviations for most of the impurity elements were less than 10%. The method has been verified to meet the requirements of quality control for the UF4 and will be used in the molten salt reactor.

A novel efficient photoelectrochemical (PEC) sensor was assembled for curcumin (Cur) detection using 2-mercaptoacetic acid (TGA)-capped CdTe nanoparticles and nickel tetra-amined phthalocyanine-linked graphene oxide (TGA-CdTe@NiTAPc-Gr). The TGA-CdTe nanoparticles could be firmly immobilized on the thin film structure of NiTAPc-Gr in a hydrogen-bonded manner, thus producing the proposed PEC sensor with a high photoelectrochemical activity of TGA-CdTe nanoparticles and excellent stability of NiTAPc-Gr. The TGA-CdTe@NiTAPc-Gr thin film showed a stronger blue light absorption property than the individual precursors, and this resulted in the sensitive detection of Cur ranging from 0.25–100 μM with a detection limit of 12.50 nM. In addition, the PEC sensor exhibited a high sensitivity and selectivity and quite good reproducibility. Thus, it shows potential for Cur detection in real samples.

The mechanism of ruthenium-catalyzed [4 + 1] annulation of benzamide and propargyl alcohol has been investigated by density functional theory calculations. The reaction undergoes N–H and C–H deprotonations by a concerted metalation-deprotonation mechanism to afford a 5-membered ruthenacyclic species, which then undergoes ring expansion by alkyne insertion to deliver a 7-membered ring intermediate. Our study focused on how the successive hydrogen migrations take place that remains unclear. The 1,2-proton migration and 1,3-proton transfer from O to C are successively finished by using acetate anion as a shuttle (a stepwise process). In contrast to the experimental proposal that the reaction experiences a Ru(II)–Ru(0)–Ru(II) transformation, our study unveiled a Ru(II)–Ru(IV)–Ru(II) transformation in the reaction. In addition, our calculations suggested that the EtO–N bond cleavage rather than the C–H activation is likely to be the rate-determining step for the entire reaction, which is not in contradiction w...

Three kinds of Cu-Sn alloy anodes with different current collectors for lithium ion batteries had been directly prepared by cost-effective and easy to scale-up electro-deposition method. Both the self-standing electrode and the electrode with polypyrrole (PPy) current collector had effects on enhancing the cycle stability and increasing the gravimetric energy density. However, due to the poor conductivity of PPy and the low crystallinity structure of Cu-Sn alloy layer, the high rate performance of Cu-Sn alloy electrode with PPy current collector was unsatisfactory, while the self-standing electrode not only greatly increased the cycle stability and energy density of the whole electrode to a large extent, but also exhibited superior high-current cycle performance. Even cycled at a current density of 6 A g−1 after 700 cycles, the self-standing electrode could still maintain a specific capacity of 332 mA h g−1, which illustrated the potential application prospect of self-standing electrode with higher energy density and power density.

The unexpected oxyamination reaction of O, ω-unsaturated alkoxyamines was found experimentally. The mechanistic issues were studied by DFT calculations. It is suggested that the reaction undergoes [3 + 2] cyclic addition, O N bond cleavage, C N reductive elimination, and the Rh N unit protonation, generating the product and regenerating the active catalyst. The nitrene Rh(V) species containing a Rh C bond rather than a Rh O bond was suggested to be involved in the reaction mechanism. Why the substrate A with X = O but not X = C undergoes oxyamination reaction was rationalized based on the suggested reaction mechanism.

Thermochemical cycles have been predominantly used for energy transformation from heat to stored chemical free energy in the form of hydrogen. The thermochemical cycle based on uranium (UTC), proposed by Oak Ridge National Laboratory, has been considered as a better alternative compared to other thermochemical cycles mainly due to its safety and high efficiency. UTC process includes three steps, in which only the first step is unique. Hydrogen production apparatus with hectogram reactants was designed in this study. The results showed that high yield hydrogen was obtained, which was determined by drainage method. The results also indicated that the chemical conversion rate of hydrogen production was in direct proportion to the mass of Na2CO3, while the solid product was Na2UO4, instead of Na2U2O7. Nevertheless the thermochemical cycle used for hydrogen generation can be closed, and chemical compounds used in these processes can also be recycled. So the cycle with Na2UO4 as its first reaction product has an advantage over the proposed UTC process, attributed to the fast reaction rate and high hydrogen yield in the first reaction step. Keywords: Thermochemical cycle, Hydrogen production, Uranium, Sodium urinate, Energy

Herein, nonstoichiometric structured tin-based anodes for lithium-ion batteries were directly prepared by a simple and traditional electrodeposition method. These tin-based anodes show high electrode capacity, excellent rate performance, and superior stable cycling stability, which delivers an outstanding reversible capacity of 728 mAh g–1 at the current density of 100 mA g–1 after 400 cycles. When cycled at the current density of 6 A g–1 for 250 cycles, the capacity of the tin-based anode was kept at about 300 mAh g–1. The tin-based anode with its nonstoichiometric structure can effectively overcome the volume expansion, stabilize the electrode structure, and enhance the cyclic stability through structural reconstruction. By improving the traditional preparation method, the excellent electrochemical anode can be obtained, which may greatly promote the commercial application of alloy mechanism anode materials in lithium-ion batteries.

Chromium (Cr) is one of the most severe heavy metal contaminants in soil, and it seriously threatens ecosystems and human health through the food chain. It is fundamental to collect toxicity data of Cr before developing soil quality criteria/standards in order to efficiently prevent health risks. In this work, the short-term toxic effects of Cr(VI) and Cr(III) on the root growth of eleven terrestrial plants were investigated. The corresponding fifth percentile hazardous concentrations (HC5) by the best fitting species sensitivity distribution (SSD) curves based on the tenth percentile effect concentrations (EC10) were determined to be 0.60 and 4.51 mg/kg for Cr (VI) and Cr (III), respectively. Compared to the screening level values worldwide, the HC5 values in this study were higher for Cr(VI) and lower for Cr(III) to some extent. The results provide useful toxicity data for deriving national or local soil quality criteria for trivalent and hexavalent Cr.

The gold(iii)-catalyzed annulations of alkynes with anthranils were evaluated using DFT calculations. A unified rationale for the Br-migration on α-imino gold(iii)-carbene was proposed, from which an unprecedented "N-donation/abstraction substitution" mechanism was established using the substituted anthranils, while direct C-H nucleophilic attack was involved with the unsubstituted anthranils. The controlling factors guiding the site-selectivity were uncovered. These computational studies provide insight for developing new α-imino gold(iii)-carbene mediated reactions.

To evaluate the effects of astragaloside on the proliferation, invasion, migration and apoptosis of nonsmall cell lung cancer A549 cells and phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin pathway. After A549 cells were treated with 0, 10, 20, 40, 60, 80 and 100 μmol/l astragaloside for 24 h, the survival rate was measured by methyl thiazolyl tetrazolium assay and the half maximal inhibitory concentration was calculated. Astragaloside at half maximal inhibitory concentration was added. Cell invasion, migration and apoptosis were detected by transwell assay, wound healing assay and flow cytometry, respectively. The effects of astragaloside on the expressions of phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin pathway-related proteins were detected by western blotting. After different concentrations of astragaloside were added, cell proliferation declined with increasing concentration. Half maximal inhibitory concentration against A549 cell proliferation was 32.2 μmol/l. Compared with blank control group; cell proliferation; invasion and migration were significantly weakened, while apoptosis was enhanced in astragaloside group. The expressions of phosphorylation of phosphatidylinositol 3-kinase, phosphorylation of protein kinase B and phosphorylation of mechanistic target of rapamycin proteins in astragaloside group were significantly lower than those in blank control group. Astragaloside inhibits the proliferation, invasion and migration, and promotes the apoptosis of nonsmall cell lung cancer A549 cells dose-dependently. Inhibiting phosphorylation of phosphatidylinositol 3-kinase, phosphorylation of protein kinase B and phosphorylation of mechanistic target of rapamycin expressions in the phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin pathway may be one of the mechanisms of astragaloside.