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As an important component of highly heterogeneous exosomes, exosomal microRNAs (miRNAs) have great potential as noninvasive biomarkers for cancer diagnosis. Therefore, a sensitive and simple sensor is the key for its clinical application. Herein, we designed an exponential amplification reaction (EXPAR) to induce the reactivation of the CRISPR-associated protein 9/small guide RNA (Cas9/sgRNA) complex, thus achieving sensitive and visual exosomal miRNAs-21 (miR-21) fluorescence sensing. In this design, we inactivated the sgRNA by hybridizing sgRNA and blocker DNA. Then, we used a trigger DNA to hybridize with miR-21 and produced a lot of activated DNA by EXPAR. Those activated DNA further hybridized with blocker DNA and released the free sgRNA to form the activated Cas9/sgRNA complex. Based on the quick cleavage of activated Cas9/sgRNA complex, the reporter DNA labeled by SYBR Green I was released from the surface of the magnetic nanoparticles (MNPs) into the supernatant, and thus was used to sensitively quantify the miRNAs concentration with a limit of detection of 3 × 103particles/mL. In addition, this fluorescence sensor has also been successfully employed to distinguish healthy people and cancer patients by naked-eye observation of the fluorescence, thus demonstrating its great potential for accurate and point-of-care cancer diagnosis.

Developing novel porous adsorbents for efficient wastewater treatment is significant to the environment protection. Herein, three porous polycalix[n]arenes (n= 4, 6, and 8) which had varying cavity sizes of the macrocycle (Azo-CX4P, Azo-CX6P, and Azo-CX8P) were prepared under mild conditions and tested for their potential application in water purification. Azo-CX8P with a larger cavity size of the macrocycle outperformed Azo-CX4P and Azo-CX6P in screening studies involving a range of organic micropollutants. It was proved that Azo-CX8P was especially efficient in the removal of cationic dyes because of its high negative surface charge. In terms of the adsorption of Rhodamine B with Azo-CX8P, the pseudo-second-order rate constant reaches 5.025 g·mg–1·min–1with the maximum adsorption capacity being 1345 mg·g–1. These values are significantly higher compared with those recorded for most adsorbents. In addition, the easily prepared Azo-CX8P can be reused at least six times without a loss of the adsorption efficiency, demonstrating its potential use in water purification.

This paper mainly studies the benefits of integrated energy services under the modes of independent investment and operation, independent investment and entrusted operation, cooperative investment and operation, and cooperative investment and entrusted operation. It also constructs a corresponding model for benefit evaluation and analysis by means of the subject feature method. This paper selects the integrated energy system of an industrial park in Southwest China as the research object. By analysing the operation modes of three different participating entities, this paper analyses their benefits by combining the cost-benefit model, and concludes that the State Grid Corporation has the greatest benefit under the independent investment and operation mode. The research results of this paper have certain practical guiding significance for the operation mode and benefit maximisation of integrated energy services.

In the context of energy shortage, the concepts of energy revolution and supply-side reform and development require the energy sector, to further promote the energy revolution, strive to promote the transformation of energy production and development, optimise the energy supply structure, improve energy efficiency, build a clean, low-carbon, safe and efficient modern energy system, and maintain national energy security. The current research on the pricing mechanism and estimation model of integrated energy services is not thorough enough. In this paper, we introduce a consistent pricing strategy and analyse the optimal decision and profit situation of manufacturers and retailers within the framework of this pricing strategy. It is found that the differentiated pricing strategy outperforms the unified pricing strategy in most cases for manufacturers and the entire supply chain. When consumers have moderate preferences for the online channel, a manufacturer's choice of a uniform pricing strategy can make it more affordable for manufacturers and suppliers, with less lost profit for the entire chain. In addition, when manufacturers have low pricing power (p< 55), they are more inclined to go for a consistent pricing strategy.

Previous research had validated the machinability of the new machining method of electrical discharge assisted milling (EDAM). However, the EDAM tool has shortcomings, such as its inability to compensate for the electrodes and small discharge area, which restricted further popularization and applications of the method. So, this research introduced a high frequency EDAM (HF-EDAM), based on a novel tool with flexible electrodes. Notably, the material removal mechanism of HF-EDAM under different machining parameters was deeply explored in this study. In particular, the discharge signal, electrode and workpiece surface topographies, cutting force, tool wear, and machined-surface integrity of HF-EDAM were analyzed to find the machining mechanism of HF-EDAM under different machining parameters. At the same time, a two-dimensional cutting force model of HF-EDAM was also established, and a series of experiments showed that the model had good prediction accuracy for cutting forces. Furthermore, the experiments also showed that the HF-EDAM greatly reduced the cutting force and tool wear, and improved the machined-surface integrity as compared to those under CM, respectively. In essence, the excellent machinability of HF-EDAM was verified by experiments and modeling. Hence, HF-EDAM is an effective method for high-quality and efficient machining of titanium alloys, which are difficult to machine.

The design and synthesis of efficient and highly selective UO22+nanotraps still pose difficulties in the field of radionuclide removal. Herein, a stable polyimide covalent organic framework (PI-COF-6) was rationally synthesized for targeted uranium adsorption through the irreversible imidization reaction between nitrogen-rich monomer 5,5′,5″-(1,3,5-triazine-2,4,6-triyl)tris(pyridin-2-amine) (TTPA) and pyromellitic dianhydride (PMDA). The PI-COF-6 showed satisfactory uranium adsorption performance with high capacity (424.5 mg g–1), fast kinetics (98.0% removal rate in 50 min), ultrahigh selectivity among multiple metal ions, excellent stability, and outstanding recyclability. XPS characterization and DFT calculations identified that the uranium adsorption of PI-COF-6 mainly relied on the N–N–O nanotraps which were rationally constructed by pyridine nitrogen in TTPA coupling with the tertiary amine nitrogen and carbonyl oxygen in the imide ring. Moreover, the results of high-resolution U 4f XPS spectroscopy revealed that part of U(VI) was reduced into U(IV). Hence, according to the design of rational nanotraps for targeted radioactive nuclides, highly effective adsorbents for practical application (rare earth mining waste remediation) were successfully achieved.

Extracting uranium from seawater offers opportunities for sustainable nuclear fuel supply, but the task is quite challenging due to the low uranium concentration (∼3 ppb) in seawater. Here, based on the Knoevenagel condensation reaction of aldehyde and acetonitrile groups, a novel stable sp2carbon-linked three-dimensional covalent organic framework (3D COF), TFPM-PDAN-AO was prepared as a porous platform for uranium extraction from seawater. The TFPM-PDAN-AO designed with regular 3D pore channel of 7.12 Å provides a specific channel for uranyl diffusion, which exhibits high selectivity and fast kinetics for uranium adsorption. Meanwhile, the superior stability and optoelectronic properties enable it an excellent porous platform for uranium electroextraction. By applying alternating voltages between −5 and 0 V, uranyl ions can rapidly migrate and enrich into the porous structure of TFPM-PDAN-AO, then inducing the electrodeposition of uranium compounds to form the charge neutral species (Na2O(UO3H2O)x) with an unprecedentedly high adsorption capacity of 4,685 mg g−1. This work not only expands the application prospects of functionalized 3D COFs, but also provides a technical support for the electrodeposition adsorption of uranium from seawater.

Copper-beryllium (UNS C17200) has been shown to be a copper alloy with combined properties of flexibility, wear resistance, and high strength. In this research, a new machining method called high-frequency electrical discharge-assisted milling (HF-EDAM) based on copper-beryllium bundle electrodes was developed for Inconel 718. In particular, the machining results of HF-EDAM under different machining parameters were studied. Notably, the HF-EDAM experiments showed that the copper-beryllium bundle electrodes could not only soften the surface of the workpiece during EDM but also effectively clean the debris generated during the milling process of HF-EDAM. At the same time, due to the flexibility of the copper-beryllium bundle electrode, the surface to be machined could be matched in real-time with the electrode, thereby effectively improving the discharge efficiency. Additionally, compared with conventional milling (CM), HF-EDAM greatly reduced the cutting force, and the machined surface quality after HF-EDAM also effectively improved. Subsequently, the excellent machinability achievable with HF-EDAM based on copper-beryllium bundle electrodes was verified by a combination of experiments and theory in this research, demonstrating HF-EDAM as an effective method for high-quality and efficient machining of Inconel 718.

Robust and antibacterial dental resins are essential for repairing the shape and function of the teeth. However, an ingenious way to achieve a synergistic enhancement of these two properties is still lacking. In this work, guided by molecular dynamics (MD) calculations, a boron nitride nanosheet (BNN)/titanium dioxide (TiO2) nanocomposite system was synthesized and used to modify the dental flow resin to enhance its mechanical and antimicrobial properties. The mechanical and antimicrobial enhancement mechanisms were further explored. The modified resin demonstrated outstanding performance improvement with 88.23%, 58.47%, 82.01%, and 55.06% improvement in compressive strength (CS), microhardness (MH), flexural strength (FS), and elastic modulus (EM), respectively. Moreover, the modified resin could effectively inhibit the growth of Streptococcus mutans(S. mutans) regardless of aging in water and the inhibition rates were more than 90%. In conclusion, the modified resin is expected to be an ideal restorative material for clinical applications.

A major barrier for organizations to act sustainably is the lack of awareness of activities that can improve their sustainability performance while creating business value. To address this, we developed the Green CompassTMmethodology and tool, which helps manufacturers develop improvement plans based on their sustainability maturity level while considering cost and value creation. Manufacturers first assess their environmental sustainability performance across their operations, supply network, and product life cycles at the strategic, tactical, and operational levels. Based on the manufacturers’ costs and value creation goals, the tool helps them prioritize issues relevant to their businesses and guides them in charting their improvement plans. Experts from 13 organizations have reviewed the Green CompassTMmethodology, and 23 organizations, including 14 manufacturers, have used the tool. This paper describes the Green CompassTMmethodology, the findings from an application example, and the analysis of data collected from the manufacturers. We found that most manufacturers actively manage the energy, water, and material impacts from their operations but not their carbon emissions, supply network, and product life cycle impacts. Green CompassTMhas broadened the manufacturers’ understanding of environmental sustainability and developed their in-house capabilities to improve sustainability.

Background and Objective: Taohong Siwu Decoction (TSD) is a classic traditional Chinese medicine (TCM) compound with pharmacological effects such as vasodilation and hypolipidemia. Paeoniflorin (PF) is one of the active ingredients of TSD. The aim of this study was to evaluate the pharmacokinetics of PF in herbal extracts and their purified forms in rats. Method: A sensitive and rapid high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS-MS) method for the determination of PF in rat plasma was developed. Rats were divided into three groups, and given PF solution, water extract of white peony root (WPR), or TSD by gavage. At different predetermined timepoints after gavage, blood was collected from the orbital vein. The pharmacokinetic parameters of PF in the plasma of rats in the three groups was determined. Results: The pharmacokinetic studies showed that the time to reach maximum concentration (Tmax) of PF in the purified forms group was relatively high, while the half-lives (T½) of PF in the TSD and WPR groups were longer. Among the three groups, PF in the purified forms group had the maximum area under the concentration–time curve (AUC0-t= 732.997 µg/L·h) and the largest maximum concentration (Cmax= 313.460 µg/L), which showed a significant difference compared with the TSD group (P&lt; 0.05). Compared with the purified group, the clearance (CLz/F = 86.004 L/h/kg) and the apparent volume of distribution (Vz/F = 254.787 L/kg) of PF in the TSD group increased significantly (P&lt; 0.05). Conclusions: A highly specific, sensitive, and rapid HPLC–MS-MS method was developed and applied for the determination of PF in rat plasma. It was found that TSD and WPR can prolong the action time of paeoniflorin in the body.

The effect of the crystal orientations and precipitates on the corrosion behavior of Al-Cu-Li single crystals was studied by scanning electron microscopy, transmission electron microscopy, optical microscopy, immersion testing in exfoliation corrosion solution, and electrochemical testing. The results show that the corrosion rates of different orientations of the aged Al-Cu-Li alloy increase in the order of (001) < (101) < (111), which are different from those of the as-quenched alloy in the increasing order of (111) < (001) < (101). The precipitation of the T1phase deteriorated the corrosion resistance of the Al-Cu-Li alloy, and the degree of deterioration differed in different crystal plane orientations. The severe localized corrosion of the aged alloy propagates along the crystallography and extends along the {111}Alplane in the form of corrosion bands.

Two new alkaloids (1and 2), named 1,7-dimethoxy-2′-prenyl-1′,9-dihydropyrrolo-carbazole (1) and 1,7-dimethoxy-4′,5′-dimethylcyclopenta-carbazole-1′,3′-dione (2), along with thirteen known alkaloids (3–15) were isolated by means of silica gel, sephadex LH-20, and semi-preparative HPLC from the CHCl3extraction of Corydalis decumbensfor the first time. Their structures were determined by NMR, MS, IR, UV, and related references. Compounds (1–15) were evaluated for their antidepressant activities by measuring inhibition of monoamine neurotransmitter reuptake in vitro. Among them, compounds 1, 2, 4, and 6showed certain antidepressant activities.

Water-and-mud inrush disasters have become a major challenge in underground engineering for the construction of tunnels in sandstone and slate interbedded Presinian strata. Disaster prediction and prevention rely in part on realistic modeling and observation of the disaster process, as well as the identification and examination of the underlying mechanisms. Based on the geological conditions and the historical records of the Xinping Tunnel on the China—Laos Railway, an engineering geological model of the water-and-mud inrush was established. A physical model test that accurately reproduced water-and-mud inrush during tunnel excavation in sandstone and slate interbedded strata was also carried out. Then, testing was conducted that examined the stress and strain, seepage pressure, and high-leakage flow of the surrounding rock. The results indicated that the water-and-mud inrush proceeded through three stages: seepage stage, high-leakage flow stage, and attenuation stage. In essence, the disaster was a catastrophic process, during which the water-resistant stratum was reduced to a critical safety thickness, a water-inrush channel formed, and the water-resistant stratum gradually failed under the influence of excavation unloading and in situ stress—seepage coupling. Parameters such as the stress and strain, seepage pressure, and flow of the surrounding rock had evident stage-related features during water-and-mud inrush, and their variation indicated the formation, development, and evolution of the disaster. As the tunnel face advanced, the trend of the stress—strain curve of the surrounding rock shifted from sluggish to rapid in its speed of increase. The characteristics of strain energy density revealed the erosion and weakening effect of groundwater on the surrounding rock. The seepage pressure and the thickness of the water-resistant stratum had a positive linear relationship, and the flow and thickness a negative linear relationship. There was a pivotal point at which the seepage pressure changed from high to low and the flow shifted from low to high. The thickness of the water-resistant stratum corresponding to the pivotal point was deemed the critical safety thickness.

Kelp (Laminaria japonica) is rich in resources and a variety of active substances. However, its fishy flavor, which is hard to remove, poses challenges to consumer preferences. This study investigated the removal of fishy odor from Saccharomyces cerevisiaeSK1.008 fermented kelp and kelp treated with fermentation combined natural antioxidant soaking through gas chromatography-mass spectrometry (GC-MS), odor activity values (OAVs) and gas chromatography-ion mobility spectrometry (GC-IMS). A total of 79 and 72 substances were identified in kelp using GC-MS and GC-IMS analysis, respectively. There were 16 volatile compounds (VOCs) with OAV>1 which were identified as key contributors to fishy odor, including (E,Z)-2,6-nonadienal, 1-octen-3-one, (E,E)-2,4-octadienal, (E,E)-2,4-decadienal and (E)-2-nonenal et al. The GC-MS analysis revealed that the removal efficiency of unsaturated aldehydes and ketones was 73.3% in kelp treated by fermentation combined soaking. The hierarchical cluster analysis and principal component analysis (PCA) constructed by GC-IMS revealed that the blank kelp, fermented kelp and kelp treated with fermentation combined soaking can be distinguished by volatile compounds. This study provides a reference for establishing a long-term effective deodorization method.

The WE43 magnesium alloy was prepared by squeeze casting, and the influence of squeeze casting parameters on mechanical properties and corrosion resistance was studied and compared with gravity casting. The gravity cast WE43 alloy shows uneven grain size distribution, and some grains even greater than 90 µm. While, the grain size of the squeeze cast WE43 alloy is mainly distributed in 20–50 µm. The Mg12Nd2Y phase morphology changes from large lamellar to strips after squeeze casting, whereas Mg24Y5phase exhibits no obvious change. The yield strength, tensile strength, and elongation of the gravity cast WE43 alloy are 127 MPa, 157 MPa, and 6%, respectively, and 145 MPa, 193 MPa, and 9.1% for squeeze cast alloy. For the squeeze cast WE43 alloy, the average corrosion rate is 0.6056 mm·year−1according to immersion test results, and according to electrochemical measurements, the corrosion current density is 78.13 µA·cm−2, which is better than that of the gravity cast WE43 alloy. Compared with gravity casting, the grains and second phase of the WE43 alloy by squeeze casting are refined, and the mechanical properties and corrosion resistance are improved. This may expand the applications of the WE43 alloy.

Background: The 2000 Centers for Disease Control and Prevention (CDC) growth charts included lambda-mu-sigma (LMS) parameters intended to calculate smoothed percentiles from only the 3rd to the 97th percentile. Objective: The objective was to evaluate different approaches to describing more extreme values of body mass index (BMI)-for-age by using simple functions of the CDC growth charts. Design: Empirical data for the 99th and the 1st percentiles of BMI-for-age were calculated from the data set used to construct the growth charts and were compared with estimates extrapolated from the CDC-supplied LMS parameters and to various functions of other smoothed percentiles. A set of reestimated LMS parameters that incorporated a smoothed 99th percentile were also evaluated. Results: Extreme percentiles extrapolated from the CDC-supplied LMS parameters did not match well to the empirical data for the 99th percentile. A better fit to the empirical data was obtained by using 120% of the smoothed 95th percentile. The empirical first percentile was reasonably well approximated by extrapolations from the LMS values. The reestimated LMS parameters had several drawbacks and no clear advantages. Conclusions: Several approximations can be used to describe extreme high values of BMI-for-age with the use of the CDC growth charts. Extrapolation from the CDC-supplied LMS parameters does not provide a good fit to the empirical 99th percentile values. Simple approximations to high values as percentages of the existing smoothed percentiles have some practical advantages over imputation of very high percentiles. The expression of high BMI values as a percentage of the 95th percentile can provide a flexible approach to describing and tracking heavier children. doi: 10.3945/ajcn.2009.28335.

The aim is to establish a model of nonalcoholic fatty liver disease (NAFLD) caused by feeding with high-fat, high-fructose, and high-cholesterol diet (HFFCD) in golden hamsters, and to investigate the characteristics of the NAFLD model and metabolite changes of liver tissue. Golden hamsters were fed HFFCD or control diets for six weeks. Body weight, abdominal fat index, and liver index was assessed, serum parameters, hepatic histology, and liver metabolites were examined. The results showed that body weight, abdominal fat, and liver index of hamsters were significantly increased in the model group, the level of serum total cholesterol (TC), triglyceride (TG), and low density lipoprotein-cholesterol (LDL-C) were significantly increased in model group as well, and high density lipoprotein-cholesterol (HDL-C) was significantly decreased. In addition, lipid deposition in liver tissue formed fat vacuoles of different sizes. Metabonomics analysis of the liver showed that the metabolic pathways of sphingolipid, glycerophospholipids, and arginine biosynthesis were disordered in the NAFLD model. The modeling method is simple, short time, and uniform. It can simulate the early fatty liver caused by common dietary factors, and provides an ideal model for the study of the initial pathogenesis and therapeutic drugs for NAFLD.

Accurate magnetic field measurement is the key to evaluating the second-order Zeeman effect. The conventional method is to deduce the magnetic field by determining the center frequency of the magnetic-field-sensitive Ramsey fringes. In this Letter, we present a more rigorous theory for this method and demonstrate that the current peak-searching method has a non-negligible sub-Hz or even larger deviation. We introduce an improved method that considers more parameters and a strict formula that can correct the deviation and suppress it to below 0.1 Hz. Corresponding experiments on the ^85Rb atomic fountain demonstrate that this improved method is expected to enhance the precision of magnetic field measurement and improve the atomic fountain clock.

ABSTRACTCisplatin (DDP) therapy is widely used for the treatment of non-small cell lung cancer (NSCLC), but the curative effect is limited by chemoresistance. This study was designed to explore circ_0020123 function in DDP resistance of NSCLCDDP. Expression detection for circ_0020123, microRNA-140-3p (miR-140-3p) and homeobox B5 (HOXB5) was performed by real-time polymerase chain reaction (qRT-PCR). Half inhibitory concentration (IC50) of DDP and cell proliferation was detected by Cell Counting Kit-8 (CCK-8) assay. Colony formation ability was assessed using colony formation assay. Cell migration and invasion were evaluated via transwell assay. Cell apoptosis was examined by flow cytometry. Protein analysis was conducted by Western blot. Dual-luciferase reporter assay was used to affirm target interaction. Circ_0020123 expression was upregulated in DDP-resistant NSCLC cells. DDP resistance was reduced by downregulation of circ_0020123 in NSCLC cells. Circ_0020123 was identified as a miR-140-3p sponge. The effect of si-circ_0020123 on DDP resistance was partly associated with miR-140-3p upregulation. HOXB5 was a downstream target for miR-140-3p. Overexpression of HOXB5 mitigated miR-140-3p-induced inhibition of DDP resistance in NSCLC cells. Circ_0020123 upregulated the level of HOXB5 partly via sponging miR-140-3p. Also, circ_0020123 promoted tumor growth in NSCLC/DDP xenografts by regulating miR-140-3p and HOXB5 levels at least in part. These results revealed that circ_0020123 promoted DDP resistance in NSCLC cells partly by targeting miR-140-3p/HOXB5 axis, indicating that circ_0020123 might be used as a molecular target in DDP treatment for NSCLC.

Coordination complexes with aggregation-induced-emission (AIE) behavior has drawn much attention because of their promising applications. Conventionally, the AIE-active metal–organic complexes are prepared from an AIE-active organic ligand, and the construction of such coordination complexes from aggregation-caused-quenching (ACQ) ligands is still challenging. Herein, we have synthesized two new cyclic trinuclear complexes (CTCs), namely, 1and 2, from copper(I) and silver(I) and a ACQ ligand [4-(3,5-dimethyl-1H-pyrazol-4-yl)benzaldehyde, HL]. (1) exhibited AIE behavior, and the emission intensity is enhanced ∼20 times when it aggregates, which can be attributed to its tight packing and multiple intermolecular hydrogen bonds that restrained the intramolecular rotation, as confirmed by single-crystal X-ray diffraction analysis. On the other hand, (2) displayed ACQ effects, and the emission intensity is decreased ∼5 times when it aggregates. This ACQ behavior of 2is related to its loose packing and free rotation of the ligand in crystals, resulting in nonradiative decay and fluorescence quenching. Interestingly, the CTCs 1and 2both exhibited a good affinity to gold(III) ions, allowing selective detection and sensing of gold ions. More importantly, the 2shows a good limit of detection (3.28 μmol/L) and an ultrafast responsive time (∼2 s). Our studies pave a new route to designing novel AIE-active coordination complexes and further exploring the functionality of CTCs.

Background: The 2000 Centers for Disease Control and Prevention growth charts for the United States include population reference data for body mass index (BMI)-for-age (ages 2-19 y) and weight-for-stature (from 77 to 121 cm). For younger children, either set of reference data could be used. Objective: The objective of this study was to compare BMI-for-age with weight-for-stature. Design: We used data for 4348 children (aged 2-5 y) from the third National Health and Nutrition Examination Survey. Weight-for-stature and BMI-for-age percentiles were calculated for each child. The 10th and 85th percentiles of weight-for-stature at selected ages were also reexpressed as BMI-for-age percentiles. Results: More than 63% of children had lower weight-for-stature than BMI-for-age percentiles. Children were more likely to be classified as [less than or equal to] 10th percentile by weight-for-stature than by BMI-for-age, but less likely to be classified as [greater than or equal to] 85th percentile. Differences in classification by the 2 measures varied with age and stature and were greater for shorter children. The 10th and 85th percentiles of weight-for-stature corresponded to BMI-for-age percentiles from the 3rd to the 21st percentile and from the 74th to the 92nd percentile, respectively, depending on age and stature. Conclusions: Weight-for-stature is easier to use than BMI-for-age. However, BMI-for-age captures changes in the weight-height relation with age and can be used continuously up to the age of 20 y. BMI-for-age is recommended in most situations. BMI-for-age and weight-for-stature will not give identical results and are not interchangeable. Am J Clin Nutr 2002; 75:761-6. KEY WORDS Body weight, body mass index, children, growth charts, health surveys, overweight, underweight, weight-for-stature, third National Health and Nutrition Examination Survey

Electrochemiluminescence (ECL), as an advanced sensing process, can selectively control the generation of excited states by changing the potential. However, most of the existing ECL systems rely on poisonous coreactants to provide radicals for luminescence; although the ECL efficiency was improved, the athematic coreactants will cause unpredictable interference to the accurate analysis of trace targets. Herein, we realized the ECL of nonemitting molecules by performing intramolecular electron transfer in the olefin-linked covalent organic frameworks (COFs), with a high efficiency of 63.7%. Employing internal dissolved oxygen as the coreactant, it is well suitable for the analysis of various complex samples in the environment. Taking nuclear contamination analysis as the goal orientation, we further illustrated a design of a “turn-on” uranyl ion monitoring system integrating fast response, low detection limit, and high selectivity, showing that new ECL-COFs are promising to facilitate environment-related sensing analysis and structure-feature correlation mechanism exploration.

Flavonolignans, for example, silymarin and silybin, have interesting biological activities. For the first time, three new flavonolignans named oenanthenoid A-C (1–3) and nine known flavonolignan derivatives (4–12) were isolated from Oenanthe javanica. Comprehensive spectroscopic data analysis and references were used to identify all of the compounds. The anti inflammatory activities of these isolates (1–12) on RAW264.7 macrophage cells were investigated. Three new compounds (1–3) demonstrated anti inflammatory activity with IC50values ranging from 6.5 ± 0.6 to 14.7 ± 1.6 µM. Furthermore, two compounds (11and 12) demonstrated moderate anti inflammatory activity, with IC50values ranging from 24.1 ± 1.2 to 62.5 ± 1.9 µM.

To investigate the capability of π–π stacking motifs to enable spin–spin coupling, we designed and synthesized three pairs of regio-isomers featuring two radical moieties joined by a [2.2]paracyclophane (CP) unit. By fusing indeno units to CP, two partially stacked fluorene radicals are covalently linked, exhibiting evident antiferromagnetic (AFM) coupling regardless of the orientation of two spins. Remarkably, while possessing high diradical indices of 0.8 and 0.9, the two molecules demonstrate good air stability by virtue of their singlet ground state. Single crystals help unravel the structural basis of their AFM coupling behaviors. When two radical centers are arranged at the pseudometa-positions around CP, the face-to-face stacked phenylene rings intrinsically confer orbital interactions that promote AFM coupling. On the other hand, if two radicals are directed in the pseudopara-orientation, significant orbital overlapping is observed between the radical centers (i.e., C9 of fluorene) and the aromatic carbons laid on the side, rendering AFM coupling between the two spins. In contrast, when two fluorene radicals are tethered to CP via C9 through a single C–C bond, ferromagnetic (FM) coupling is manifested by both diradical isomers featuring pseudometa- and pseudopara-connectivity. With minimal spin distributed on CP and thus limited contribution from π–π stacking, their spin–spin coupling properties are more similar to a pair of nitroxide diradical analogues, in which the two spins are dominantly coupled via through-space interactions. From these results, important conclusions are elucidated such as that although through-space interactions may confer FM coupling, with weakened strength shown by PAH radicals due to their lower polarity, face-to-face stacked π-frameworks tend to induce AFM coupling, because favorable orbital interactions are readily achieved by PAH systems hosting delocalized spins that are capable of adopting varied stacking motifs.

Polymorphism is known to show a significant effect on the crystal packing structures and physical properties of molecular complexes. On the basis of our previous works on the spin-crossover (SCO) complex [Fe(tpa)(NCS)2] (tpa = tris(2-pyridylmethyl)amine), we have prepared the analogous complex [Fe(tpa)(NCSe)2] using a NCSe–coligand and obtained a series of crystalline polymorphs, namely SeI–SeIV, respectively, by controlled synthetic processes. Single-crystal X-ray diffraction studies reveal that these polymorphs show different packing modes and different intermolecular interactions. Various SCO behaviors are thus observed. Moreover, an obvious coligand effect on SCO behaviors is found by a comparison of the present study and the reported complex [Fe(tpa)(NCS)2]. The NCSe–complexes show a critical shift of T1/2values to a higher temperature range and a more gradual transition process in comparison to those for the isostructural complexes using NCS–, indicating a stronger ligand-field strength and a weaker cooperativity for the NCSe–coligand.

Background: Evidence of the association between marital status and cognitive function in Chinese older adults is limited. Aims: To examine the relationship between marital status and cognitive function and to explore the role of gender amongst older adults from three Chinese communities. Methods: A total of 1376 participants aged 60 years or over were included in this cross-sectional study. Cognitive function was assessed using the Chinese version of the mini-mental state examination (MMSE). Marital status and other variables were collected using a standardized questionnaire. Multiple linear regression models were used to examine associations between marital statuses and cognitive function amongst the target population. The moderating role of gender in these potential associations has also been explored. Results: In univariate linear regression models, compared to being married, both being widowed (β[95% CI]: −1.46[−2.78 to − 0.13]) and being single (β[95% CI]: − 4.88[−6.43 to − 3.38]) were associated with lower MMSE scores. After adjustment for confounding factors, the significant association of being widowed with MMSE scores disappeared (β[95% CI: − 0.08[− 1.04 to 0.86]), but the association of being single with MMSE scores still existed (β[95% CI]: − 1.87[− 3.17 to − 0.58]). Furthermore, the association of being single with MMSE scores was statistically significant in men (β[95% CI]: − 5.25[− 7.17 to − 3.33]) but not in women (β[95% CI: 0.88[− 0.87 to 2.64]). Discussion and conclusions: Being single was associated with poorer cognitive function compared with their married counterparts in older Chinese men but not in women. More preventive measurements should be implemented for single men to reduce or delay cognitive decline. This is particularly important in the context of an aging population in China.

Rigid molecular sieving materials work well for small molecules with the complete exclusion of large ones1–3, and molecules with matching physiochemical properties may be separated using dynamic molecular sieving materials4–6. Metal–organic frameworks (MOFs)7–9are known for their precise control of structures and functions on a molecular level10–15. However, the rational design of local flexibility in the MOF framework for dynamic molecular sieving remains difficult and challenging. Here we report a MOF material (JNU-3a) featuring one-dimension channels with embedded molecular pockets opening to propylene (C3H6) and propane (C3H8) at substantially different pressures. The dynamic nature of the pockets is revealed by single-crystal-to-single-crystal transformation upon exposure of JNU-3a to an atmosphere of C3H6or C3H8. Breakthrough experiments demonstrate that JNU-3a can realize high-purity C3H6(≥99.5%) in a single adsorption–desorption cycle from an equimolar C3H6/C3H8mixture over a broad range of flow rates, with a maximum C3H6productivity of 53.5 litres per kilogram. The underlying separation mechanism—orthogonal-array dynamic molecular sieving—enables both large separation capacity and fast adsorption–desorption kinetics. This work presents a next-generation sieving material design that has potential for applications in adsorptive separation.

ABSTRACTDue to the nature of their work, tour leaders need to interact closely with the tour members; thus, the former are often subjected to emotional blackmail by the latter. Therefore, this study investigated the relationship among tour leaders’ perceived emotional blackmail, job frustration, and turnover intention. Licenced tour leaders were chosen as participants of this study and were asked to answer a self-administered survey questionnaire. A total of 355 valid questionnaires were collected at the end of the study period. The results showed that the higher the tour leaders’ perceived blackmail, the higher the job frustration and the turnover intention are. Furthermore, based on the results, job frustration has a positive effect on turnover intention.

Magnetic-sensitive Ramsey fringes are useful for the magnetic field evaluation of atomic fountain clocks. However, broadening mechanisms affect the visibility of the fringes and limit their application for measurement of the magnetic field. The magnetic-induced Rabi broadening, which comes from the magnetic field inhomogeneity in the microwave cavity of fountain clocks and results in the visibility reduction of the fringes, is demonstrated in this paper. Furthermore, an improved method to shorten the Rabi interaction time is proposed to suppress the broadening effect. Experiments are conducted on the rubidium 87 atomic fountain clock to test the broadening mechanism as well as to demonstrate the effectiveness of the improved method to suppress the broadening effect. As a result, we obtain magnetic-sensitive Ramsey fringes and evaluate the average magnetic field. The second-order Zeeman frequency shift also is evaluated with a fractional frequency shift of 1.295×10^−13, and a frequency uncertainty of 3×10^−16.

Lithium-oxygen batteries have a wide application due to their ultra-high theoretical energy density. However, uncontrollable lithium dendrites and highly reactive oxygen species greatly cause the corrosion of lithium anodes and the degradation of the electrolytes. In our work, we introduce 4-Methylbenzenesulfonyl Fluoride (4-MBSF) as a highly efficient film-forming additive. It can form a stable inorganic-organic composite solid electrolyte interfacial layer and inhibit the growth of lithium dendrites to stabilize the lithium anode, thus dramatically enhancing the lives of lithium-oxygen batteries. The sulfonyl fluoride group of 4-MBSF can react with LiOH to form a LiF-rich protective layer on the lithium metal surface, which can improve stripping/deposition stability and ionic conductivity. Besides, the π-conjugation of the benzene ring can improve the flexibility of the SEI layer to accommodate volume changes of the lithium anode during cycling and inhibit the attacks of the reactive oxygen species. The cycle life of lithium-oxygen batteries with 4-MBSF is prolonged to 400 cycles.

This study explores a new method to maximize the visible-light-driven photocatalytic performance of organic–inorganic hybrid polyoxometalates (POMs). Experimental and theoretical investigations of a family of phosphonate-substituted POMs show that modification of grafted organic moieties can be used to tune the electronic structure and photoactivity of the metal oxide component. Unlike fully inorganic polyoxotungstates, these organic–inorganic hybrid species are responsive to visible light and function as photocatalysts (λ > 420 nm) in the decomposition of a model environmental pollutant. The degree of photoactivation is shown to be dependent on the nature of the inductive effect exerted by the covalently grafted substituent groups. This study emphasizes the untapped potential that lies in an orbital engineering approach to hybrid-POM design and helps to underpin the next generation of bespoke, robust, and cost-effective molecular metal oxide photoactive materials and catalysts.

Dental resin composites (DRCs) are commonly used to restore teeth affected by dental caries or defects. These materials must possess excellent properties to withstand the complex oral environment. The objective of this study was to prepare and characterize Boron nitride nanosheets (BNN)/ dimethyl amino hexadecyl methacrylate (DMAHDM) composites (BNN/DMA), and to evaluate them as functional fillers to enhance the mechanical and antimicrobial properties of dental resins. The BNN/DMA composites were successfully prepared under the theoretical guidance of molecular dynamics (MD), and then the physicochemical and morphological characterization of the BNN/DMA composites were carried out by using various test methods, such as FT-IR, XRD, UV–vis spectroscopy, SEM, TEM, and AFM. It was doped into the dental flowable resin in a certain proportion, and the results showed that the flexural strength (FS), elastic modulus (EM), compressive strength (CS), and microhardness (MH) of the modified resin composites were increased by 53.29, 47.8, 97.59, and 37.1%, respectively, with the addition of 0.8 wt % of BNN/DMA composite fillers. It has a good inhibition effect on Streptococcus mutans, with an inhibition rate as high as 90.43%. Furthermore, this effect persists even after one month of aging. In conclusion, the modification of flowable resins with low-concentration BNN/DMA composites favorably integrates the mechanical properties and long-term antimicrobial activity of dental resins. At the same time, they have good biocompatibility and do not affect the aesthetics. The BNN/DMA composite modified flowable resin has the potential to become a new type of antimicrobial dental restorative material.

Over the past years, perylenediimide (PDI)-based polymers have emerged as one of the widely studied polymer acceptors applicable to all-polymer solar cells (PSCs) due to their outstanding photovoltaic properties. Covalently fused PDI units, such as naphthodiperylenetetraimide (NDP), are proven beneficial to increasing the regularity of polymer backbones and enhancing the molecular packing in blend films, thus optimizing the active-layer morphology and improving the device performance. However, most investigated PDI polymers commonly demonstrated low open-circuit voltage (Voc) in solar cells due to their low-lying lowest unoccupied molecular orbital (LUMO), which greatly limited the power-conversion efficiencies (PCEs) of their devices. Herein, we design and synthesize two new polymer acceptors (PTP-TT and PTP-Th) using thiophene-fused dimeric PDI (i.e., PTP) as the key building block. Both polymers exhibit much elevated LUMO levels at ca. −3.8 eV and achieve higher Vocin devices compared with NDP-derived polymers. In particular, PTP-TT exhibits stronger light-absorption ability than PTP-Th and a presumably more planar backbone conformation, which are favorable for molecular packing and charge carrier transport in the active layer. Using PTB7-Th as the donor, PTP-TT-based devices achieve the best PCE of 7.04%, with a Vocof 0.86 V, a short-circuit current density of 14.96 mA/cm2, and a fill factor of 54%. The current results demonstrate that fusing PDIs with a proper electron-rich moiety can synergistically elevate the LUMO level and optimize the backbone regularity of polymer acceptors to obtain desirable efficiencies of PSCs.

Ocular changes are traditionally associated with only a few hepatobiliary diseases. These changes are non-specific and have a low detection rate, limiting their potential use as clinically independent diagnostic features. Therefore, we aimed to engineer deep learning models to establish associations between ocular features and major hepatobiliary diseases and to advance automated screening and identification of hepatobiliary diseases from ocular images.

A unique metal–organic framework (MOF) with tetrazole-padded helical channels has been successfully synthesized in one pot from iron(II) trifluoromethanesulfonate, 4-formylimidazole, hydrazine, and sodium azide under solvothermal conditions and features a rare unhtopology and porous structure for gas adsorption. Transformations of condensation, cycloaddition, and coordination occurred during the synthetic process, in which a 1,5-disubstituted tetrazole ligand was formed in situ.

Bioactivity-guided phytochemical investigation of Cucumis bisexualishas led to the isolation of three new coumarin-aurone heterodimers (1-3), along with six aurone derivatives (4-9) were isolated from C. bisexualisfor the first time. Their structures were determined by their extensive spectroscopic data and comparison with the values reported in the references. All isolated compounds (1-9) were evaluated for their hepatoprotective activities on human L-O2 cells, which compared with positive control of Bifendatatum. Among them, compounds 1, 2, and 7exhibited moderate hepatoprotective activities to promote effects on the proliferation of L-O2 cells.

The hybrid electrode of single-wall carbon nanotubes (SWCNTs)/Cu2O/ZnO nanorods (NRs)/graphene used on the current-response nonenzymatic glucose sensor was investigated herein, regarding the mechanism of the formation of functional channel. The synthesis of the hybrid electrode involved four steps. First, the graphene was grown by chemical vapor deposition (CVD) and then wet-transferred onto indium transparent oxide (ITO) glass. Second, a zinc oxide (ZnO) seed layer was sputtered onto the graphene/ITO glass, and ZnO NRs were gradually grown by the hydrothermal method. Third, the ZnO NRs were clad with cuprous oxide (Cu2O) by the electrochemical method. Fourth, the SWCNTs were dropped onto the Cu2O surface, with a Nafion surfactant. X-ray diffraction spectra, scanning electron microscopy spectra, Raman spectra, cyclic voltammograms, and amperometric response diagrams were used to verify the performance of the device. Results showed that sensitivity increased significantly from 11.2 to 289.8 μA mM–1cm–2, linear range increased significantly from 0.6 to 11.1 mM, and the coefficient of determination (R2) increased from 0.9766 to 0.9923, all by the addition of the SWCNTs/Cu2O functional channel mechanism and without graphene. When the graphene was added to the functional channel electrode, sensitivity increased again from 289.8 to 466.1 μA mM–1cm–2at low concentrations.

The fruit of Hippophae rhamnoidesL. has been used for centuries in Europe and Asia as a food with high nutritional and medicinal values. In this study, a bioactivity-guided phytochemical investigation of H. rhamnoidesL. has resulted in four new dimethylallylated flavonolignans (1–4), four new isopropylpentenone–flavonolignan heterodimers (5–8), two new geranylated flavonolignans (9and 10), and 14 known flavonolignan derivatives (11–24); they were elucidated by their spectrometric and spectroscopic methods, including HR-ESI-MS, NMR, IR, and UV from the fruit of H. rhamnoidesL. for the first time. Among them, compounds 2, 5, 6, 20, and 21showed potent immunosuppressive activities with IC50values from 19.42 ± 3.91 to 48.05 ± 12.56 μM. Meanwhile, compounds 1, 4, 11, 12, and 13showed moderate neuroprotective activities, which increased the cell survival rate from 50.30 ± 4.24% for the model group to 71.63 ± 3.04%, 70.02 ± 4.13%, 61.53 ± 5.93%, 61.08 ± 3.58%, and 65.68 ± 4.88% at 10 μM, respectively. The hypothetical biogenetic pathway and preliminary structure–activity relationship were found and discussed scientifically.

Potentilla anserinaL. is not only a medicinal plant, but also a traditional cuisine. Hence, an acute toxicity study was performed to confirm its safety profile. Forty Kunming mice were randomly divided into two groups: control group and P. anserinaL. extract group. Using the maximum dosage method, the P. anserinaL. extract group was given the maximum dose within 12 h, equivalent to 345.6 g/kg crude drug. The control group was given distilled water. After administration, toxicity symptoms of mice were observed, body weight and food intake were recorded. After 14 days, blood was collected to measure biochemical parameters, autopsy was carried out to observe the changes of organs, and the vital organs were separated, weighed, and preserved for histopathological examination. The results showed that P. anserinaL. extract group had no toxic symptoms. The activity, weight, and diet of mice were normal, and no abnormality was found in organ index, renal function, liver function, anatomical observation, and histopathological examination. Therefore, the maximum oral dosage (345.6 g/kg) of P. anserinaL. was good safety. This study indicated that P. anserinaL. had a large safety range and the clinical application was safe.

Long non-coding RNAs (lncRNAs) have been identified as essential mediators in neurological dysfunction. Our previous study shows that berberine (BBR) hampers the nuclear-to-cytosolic translocation of high-mobility group box 1 (HMGB1) in the process of poststroke inflammation. In this study, we explored the role of lncRNA metastasis‐associated lung adenocarcinoma transcript 1 (Malat1) in the process of BBR-induced inhibition of HMGB1 in ischemic brain. Before the 60-min MCAO surgery, the mice were pretreated with BBR (50 mg· kg−1per day, ig) for 14 days or ICV injected with specific lentiviral vector or shRNA. We showed that MCAO caused marked increase in the expression Malat1 and HMGB1 in the ipsilateral cortex, which was significantly attenuated by pretreatment with BBR. Knockdown of Malat1 attenuated the inflammatory injury after brain ischemia, whereas overexpression of Malat1 exacerbated ischemic brain inflammation. Overexpression of Malat1 also reversed BBR-induced reduction of HMGB1 and proinflammatory cytokines. The above results suggested a potential correlation between Malat1 and stroke inflammation. Based on informatics analysis we predicted that HMGB1 was a direct downstream target of miR-181c-5p, whereas Malat1 acted as a competitive endogenous RNA (ceRNA) for miR-181c-5p targeted the 3′-UTR of HMGB1 to promote inflammation after ischemic stroke. Knockdown of Malat1 significantly decreased HMGB1 level, which could be abrogated by transfection with miR-181c-5p inhibitors. Taken together, our results demonstrate for the first time that Malat1/miR-181c-5p/HMGB1 axis may be a key pathway of BBR-induced antiinflammation effects in stroke, and they may provide a novel avenue for targeted therapy.

As one of the most important elements in the nuclear industry, uranium has both radioactivity and chemical toxicity, which can harm human beings when released into the natural environment. It is difficult for most uranium adsorbents to maintain good stability under strong radiation and acid conditions. Therefore, it is highly desirable to develop a stable adsorbent for the rapid detection and efficient removal of uranium. Herein, we first constructed an amidoxime-functionalized luminescent sp2carbon linked covalent organic framework (TP-COF-AO), which is rich in amidoxime groups, has open 1D channels and an extraordinarily stable framework. Based on these advantages, it can reduce UO22+from 9.25 ppm to below 10 ppb within 10 min and has a high adsorption capacity (436 mg g−1). Meanwhile, the adsorption of UO22+on TP-COF-AO results in rapid fluorescence quenching (within 2 s) with an ultra-low detection limit (8.3 nM), which is well below the maximum contamination standard in drinking water prescribed by the U.S. Environmental Protection Agency (130 nM). Moreover, it also has excellent recyclability that provides possibility for practical applications. This study indicates that the sp2carbon-conjugated COF can be used for the simultaneous detection and adsorption of UO22+with good application prospects in environmental applications.

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