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A simple one-step approach that only uses commercially available small-molecule reagents was developed for the construction of metal-organic framework (MOF)@polymer core-shell composite particles. Here, the MOF particles were incorporated into a typical reversible addition-fragmentation chain-transfer (RAFT) polymerization solution containing a solvent, a chain-transfer agent, an initiator, and a monomer mixture with at least one hydrogen-bond-donating monomer such as 2-hydroxyethyl methacrylate or acrylic acid. The elongation of polymer chains during polymerization gradually increases MOF/polymer interfacial interaction and eventually results in the adsorption of a random copolymer onto the MOF surface through hydrogen-bond cross-linking and MOF/polymer interfacial interaction. The continuous growth of the polymer leads to a uniform polymer coating on the MOF. Benefiting from the tacky polymer surface, these well-defined MOF@polymer composite particles can be further assembled into highly ordered monolayer composite thin films either alone or with an additional polymer matrix through the Langmuir-Blodgett technique.

Cisplatin is a chemotherapeutic agent widely employed in the treatment of various solid tumors. However, its use is often restricted by acute kidney injury (AKI) which is the dose-limiting adverse effect of cisplatin. While numerous studies aiming to alleviate the AKI have been conducted, there are no effective remedies in clinical practice. In this paper, a targeted metabolomics study was performed to reveal the potential relationship between tryptophan metabolism and cisplatin-induced AKI. A chemical derivatization integrated liquid chromatography coupled tandem mass spectrometry (LC-MS/MS) approach was utilized to quantify 29 metabolites in the tryptophan pathway in rat kidney medulla and cortex after cisplatin administration. Results showed that tryptophan metabolism was remarkably disturbed both in the medulla and cortex after cisplatin administration. We also found that the tryptophan pathway in the medulla was more sensitive to cisplatin exposure compared with the cortex. Among these metabolites, indoxyl sulfate was focused for further study because it accumulated most significantly in the kidney cortex and medulla in a dose-dependent manner. A function verification study proved that chlormethiazole, a widely used CYP2E1 inhibitor, could reduce the production of indoxyl sulfate in the liver and attenuate cisplatin-induced AKI in rats. In conclusion, our study depicted the tryptophan pathway in cisplatin-induced AKI for the first time and demonstrated tryptophan metabolism is closely associated with the renal toxicity caused by cisplatin, which can be of great use for the discovery of renal toxicity attenuating remedies.

The signal of phytoplankton responses to climate-related forcing can be obscured by the heterogeneity of shelf seascapes, making them difficult to detect from fragmented observations. In this study, a physical–biological model was applied to the Northwest Atlantic Shelf to capture the seasonality of phytoplankton. The difference in phytoplankton seasonality between the Mid-Atlantic Bight (MAB) and the Gulf of Maine (GoM) is a result of the interplay between nutrients and temperature: In the MAB, relatively high temperature in the cold season and longer oligotrophic environment in the warm season contribute to an earlier winter bloom and a later fall bloom; in the GoM, low temperature and strong mixing limit phytoplankton growth from late fall to early spring, resulting in a later spring bloom and an earlier fall bloom. Although the temperature difference between the GoM and the MAB might decrease in the future, stratification and surface nutrient regimes in these two regions will remain different owing to distinct thermohaline structures and deep-water intrusion. The spatial heterogeneity of phytoplankton dynamics affects pelagic and benthic production through connections with zooplankton and benthic–pelagic coupling.

The present study aims to investigate the influences of potassium (K) supply and harvest time on selected growth, physiology and quality factors of Ephedra sinica Stapf (ESS). A field plot experiment was conducted under 10 levels of K supply (K1–K10, 0–538.3 kg ha−1). ESS was sampled randomly with uniform distribution locations of each plot on August 27 (H1), September 15 (H2), October 6 (H3), and October 27 (H4) in 2018. The late-harvested ESS had low SPAD value, peroxidase activity, cell membrane permeability, and high 10 cm stem weight, phenylalanine ammonia-lyase activity, free proline, ephedrine, total alkaloids, or flavonoids contents. The fertilizer dose of 59.8–239.3 kg ha−1 (K2-K5) increased the 10 cm stem weight, stem or root fresh and dry weights, the SPAD value, free proline content, peroxidase activity, reduced the root activity. The ephedrine, pseudoephedrine, total alkaloids, and flavonoids contents increased with the increase of K supply before K7 (358.9 kg ha−1). The harvest time influenced the increase of these quality factors resulting from one unit of K application. The harvested E. sinica in H3 increased the ephedrine content 85.97%, pseudoephedrine 21.53%, total alkaloids 38.02%, and total flavonoids 66.43%, compared with their average values of H1. The dose of 239.3 kg ha−1 (K5) reduced the ephedrine content 14.99%, pseudoephedrine 8.07%, total alkaloids 16.4%, and total flavonoids 28.71%, compared with K7, however increased the stem fresh and dry weight 163.21% and 125.70%, respectively. The late-harvested ESS had high contents of quality factors and good quality. The K dose of 239.3 kg ha−1 was appropriate for cultivated ESS high yield and quality accumulation.

The defects including halide vacancies and uncoordinated Pb in perovskite films caused by the cracking of Pb–I bonds in the thermal annealing process are responsible for the degradation of the photovoltaic performance and long-term stability of perovskite solar cells (PSCs). Passivation of halide vacancies and uncoordinated Pb defects and construction of high quality perovskite films are vital to promote carrier lifetime and reduce non-radiative recombination losses. Herein, we develop a facile and broadly applicable surface passivation strategy for various compositional perovskite films, in which cadmium bromide (CdBr2) is selected and adopted to passivate the halide vacancies and uncoordinated Pb defects of the perovskite films owing to the stronger bond energies of Cd–I and Pb–Br than that of Pb–I. CdBr2 modification is found to be able to prolong carrier lifetime and decrease defect amount together with improving film quality of the typical compositional perovskites i.e. MAPbI3, Cs0.15FA0.85PbI3 and CsPbI2Br, as evidenced by spectral and photoelectrochemical measurements. As a result, the photovoltaic performance and ambient, photo and thermal stability of perovskite devices are greatly promoted, with a high efficiency of 16.05% achieved by the CdBr2-modified PSCs with the architecture of ITO/SnO2/MAPbI3/carbon, exceeding the previous highest PCE record for carbon-based MAPbI3 PSCs.

We firstly establish a facile one-step ring-closure methodology to obtain a novel macrocyclic tellurocarbonate (MTe) series. The well-defined poly(telluride-carbonate)s (PTe) were developed by one-pot organocatalytic ring-opening polymerization (ROP) of MTe. This work furnishes a strategy for utilizing heterotellurium macrocarbonates as feedstocks in polymer synthesis of degradable tellurium-containing materials.

An atomic-level picture of molecular and bulk processes, such as chemical bonding and charge transfer, necessitates an understanding of the dynamical evolution of these systems. On the ultrafast timescales associated with nuclear and electronic motion, the temporal behaviour of a system is often interrogated in a 'pump-probe' scheme. Here, an initial 'pump' pulse triggers dynamics through photoexcitation, and after a carefully controlled delay a 'probe' pulse initiates projection of the instantaneous state of the evolving system onto an informative measurable quantity, such as electron binding energy. In this paper, we apply spectral ghost imaging to a pump-probe time-resolved experiment at an X-ray free-electron laser (XFEL) facility, where the observable is spectral absorption in the X-ray regime. By exploiting the correlation present in the shot-to-shot fluctuations in the incoming X-ray pulses and measured electron kinetic energies, we show that spectral ghost imaging can be applied to time-resolved pump-probe measurements. In the experiment presented, interpretation of the measurement is simplified because spectral ghost imaging separates the overlapping contributions to the photoelectron spectrum from the pump and probe pulse.

Nitrite oxidation is the primary pathway that generates nitrate in engineered systems. However, little is known about the role of a novel nitrite-oxidizing bacteria (NOB) genus Candidatus Nitrotoga in activated sludge systems. To elucidate key factors that impact NOB community composition, laboratory-scale sequencing batch reactors (SBRs) were designed and operated under the same conditions as real wastewater treatment plants to achieve considerable nitrogen removal and similar community; then, different conditions including temperature (T), dissolved oxygen (DO), free nitrous acid (FNA), and free ammonia (FA) were applied. The 16S rRNA gene-based PCR and sequence analysis illustrated that Ca. Nitrotoga were abundant even at ambient temperature, thus further challenging the previous conception of them being solely cold-adapted. Ca. Nitrotoga are less competitive than Nitrospira during oxygen deficiency, indicating its lower affinity to dissolved oxygen. Ca. Nitrotoga are the dominant nitrite oxidizers under regular exposure to FNA and FA due to their relatively higher resistance than other NOB toward these two effective biocides. Therefore, this study demonstrates that Ca. Nitrotoga can play an important role in biological nitrogen removal and also highlights the need for multiple strategies for NOB suppression for the next-generation, shortcut nitrogen removal.

In order to sustainably transform N2 to ammonia (NRR) using electrocatalysts under mild ambient condition, it is urgent to design and develop non-nobel metal nanocatalysts that are inexpensive and suitable for mass-production. Herein, a calcium metalate catalyst CaCoOx with oxygen vacancies was synthesized and used as an electrocatalyst for NRR for the first time, whose morphology can be controlled by the calcination temperature and the heating rate. Under the optimal conditions, the CaCoOx catalyst achieved the yield of nitrogen conversion to ammonia of 16.25 µg·h−1·mgcat−1 at the potential of −0.3 V relative to the reversible hydrogen electrode (RHE) with a Faraday efficiency of 20.51%. The electrocatalyst showed good stability even after 12 times recyclability under environmental conditions and neutral electrolyte. Later, the electrocatalytic nitrogen reduction performance of CaFeOx, CaNiOx, CaCuOx was investigated. These earth-rich transition metals also exhibited certain NRR electrocatalytic capabilities, which provided a door for further development of inexpensive and easily available transition metal as nitrogen reduction electrocatalysts.

It has been hypothesized that vanadium (V) isotopes have the potential to track sedimentary redox conditions due to multiple valence states occurring in nature, which might induce variable V isotope fractionation as a function of sedimentary redox state. These characteristica could make V isotopes a useful paleo-redox proxy. However, in order to understand the mechanisms driving V isotope fractionation, it is crucial to build a framework for the depositional and post-depositional controls on sedimentary V isotope records from a diverse set of sedimentary environments. This study, for the first time, investigates the V isotope variations of modern marine sediments deposited under a range of redox environments. Our results document that changes in local redox conditions impart a significant isotopic fractionation from seawater as recorded in the local sedimentary V isotopic signature. Importantly, there is a significant difference between the V isotope composition of sediments deposited in the open ocean setting with oxygen-deficient bottom waters compared to less reducing environments, whereby oxic sediments (benthic oxygen contents > 10 μΜ) exhibit Δoxic = −1.1 ± 0.3‰ and anoxic sediments exhibit Δanoxic = −0.7 ± 0.2‰. Combined with previous studies on seawater particulate and sediment pore fluid analysis, our results indicate that V is mainly delivered and enriched in anoxic sediments through settling particulates. Authigenic V isotope compositions in marine sediments are likely controlled by isotope fractionation between V species bound to particulates and dissolved in seawater, which likely varies with the speciation and adsorption properties of V that are strongly controlled by local redox conditions. In addition, the euxinic Cariaco Basin sediments exhibit distinctive Δeuxinic = −0.4 ± 0.2‰, which is likely influenced by the relationship between the seawater V removal rate and the seawater renewal rate. Our results highlight the direct link between authigenic marine sedimentary V isotope compositions and the overlying local redox conditions. This investigation of V isotopes in modern marine environments provides an initial framework for the utilization of V isotopes to reconstruct ancient redox fluctuations, which has the potential to track subtle redox variations of local oxygen-deficient to low oxygen environments.

Mineral nutrients play important roles in the growth and metabolism of Ephedra intermedia, and are affected by soil factors. Fifteen elements were measured from wild E. intermedia as well as their growing soils using inductively coupled plasma mass spectroscopy to investigate the influences and characteristics of herb elements. The pH, cation exchange capacity, humus and soil mechanical composition were also determined in rhizosphere soils. Results showed that E. intermedia stems contained high N, low P concentrations in macronutrients and high Fe in micronutrients, and enriched N, S, Cl, P and Sr from soils. The 15 herb elements were affected by one or more soil factors, and K, P, Zn, Fe and Mn were important soil elements that influenced the mineral accumulation of E. intermedia. This study was useful for the artificial cultivation of wild E. intermedia.

Background Improving the quality attributes and nutritional profiles of functional foods has been a major focus of research in recent years. Enzymatic modification of food molecules can be used to enhance their functional performance in foods. Laccase, peroxidase, and tyrosinase can catalyze the oxidation of proteins, polysaccharides, and polyphenols, and have great application potential in the construction of food colloids. Scope and approach This review summarizes and compares the catalytic mechanisms of laccase, peroxidase, and tyrosinase for the modification of food molecules and their applications in colloidal systems, as well as highlighting the advantages of combining different oxidases. Key findings and conclusions Laccase, peroxidase and tyrosinase catalyze the oxidation of food molecules in two steps. The first step involves an enzymatic reaction to generate free radicals or quinones; the second step involves a non-enzymatic reaction of free radicals or quinones with other molecules. Enzymes mainly play a role in initiating reactions in the whole process, which generally requires the participation of phenolic substances. In addition, polysaccharides and proteins containing phenolic groups can also be directly cross-linked. Peroxidase seems to have the most extensive catalytic substrates among the three oxidases reviewed. The cross-linking of food molecules induced by these oxidases helps to improve the formation and stability of colloidal systems, such as emulsions, nanoparticles, and microgels, thereby enhancing their potential for encapsulating, protecting, and delivering bioactive compounds. Employing a combination of different oxidases in food colloids can overcome the limitations of single oxidase and improve the functionality of the overall system.

Awareness concerning the degradation of groundwater quality and their exacerbating adverse effects due to salinization processes is gaining traction, raising for adequate understanding of the distribution, sources, genesis, and environmental concerns of salinity in groundwater. Saline groundwater is widely distributed all over the world, with an area of 24 million km2 (16% of the total land area on earth) and 1.1 billion people living in the affected areas, especially the arid/semi-arid areas in developing countries. These large-scale groundwater salinization problems are sourced from two major ways: natural and anthropogenic. The natural sources are diversified from connate saline groundwater, seawater intrusion, evaporation, dissolution of soluble salts, membrane filtration process to geothermal origin. The anthropogenic sources include irrigation return flow, road deicing salts, industrial and agricultural wastewater, and gas and oil production activities. The integrated approach of geochemical tracers and multiple isotopes (δ18OH2O, δ2HH2O, δ11B, δ36Cl, δ34Ssulfate, 87Sr/86Sr, and δ7Li) is proved to be useful in the constraints of the origin and transport of solutes in groundwater. Groundwater salinization is often associated with high levels of some toxic elements like arsenic, fluoride, selenium, and boron. Four "triggers" lead to this association: salt effect, competing adsorption, microbial processes, and cation exchange.

In practice, seismic intensity is evaluated in accordance with a macroseismic-intensity scale recognized in the field of seismic engineering globally. The application of different seismic-intensity scales to evaluate the seismic damage of a specific structure due to an earthquake yields diverse results. On this basis, this study compared a few extensively used macroseismic-intensity scales. The results can be used as a reference to develop an international intensity scale. According to empirical structural-damage survey data from the Wenchuan earthquake (Mw = 8.0) that occurred on 12 May 2008 in China, the European Macroseismic Scale (EMS)-98, Medvedev, Sponheuer, and Karnik (MSK)-81, and Chinese Seismic Intensity Scale (CSIS)-08 intensity scales were utilized to evaluate the resulting damage. This study carried out a vulnerability analysis of typical structures, established vulnerability seismic-damage matrices, and mapped out vulnerability curves under different intensities. Our objective is to demonstrate that the use of multiple intensity scales can lead to very different intensity levels. The differences in the damage of typical structures under different intensity levels were obtained from an evaluation using the three aforementioned intensity scales. As a result, a calculation model of the mean damage index is proposed herein. Ultimately, this article conducted an analysis on the failure characteristics of typical structures in an earthquake and provided effective measures to improve seismic performance for future reference.

In order to investigate the protective effects of Rhodiola crenulata extract on Alzheimer's disease, a brain metabolomics study in rats was conducted by high performance liquid chromatography coupled with Fourier transform ion cyclotron resonance mass spectrometry. Rat model was constructed by bilateral hippocampal injection of amyloid-β peptide and immunohistochemistry was performed to evaluate the pharmacological effect of Rhodiola crenulata extract. Multivariate statistical analysis was used to discover potential biomarkers in rat brain and related metabolic pathways analysis was conducted to elucidate the action mechanism of Rhodiola crenulata extract. As a result, a total of 19 metabolites contributing to Alzheimer's disease progress were identified and nine of them were restored to the normal levels after drug administration. Pathway analysis revealed that the protective effects of Rhodiola crenulata extract are related to the regulation of glutathione metabolism and arachidonic acid metabolism in rat brain. In conclusion, this work demonstrates that the developed metabolomics method is useful to investigate the protective effects of Rhodiola crenulata extract against Alzheimer's disease. These outcomes may further provide reliable evidence to illuminate the intervention mechanism of other traditional Chinese medicines on Alzheimer's disease.

To meet increasing demands, tea plantations are rapidly expanding in China. Although the emissions of nitrous oxide ( N2O ) and nitric oxide (NO) from tea plantations may be substantially influenced by soil pH reduction and intensive nitrogen fertilization, process model-based studies on this issue are still rare. In this study, the process-oriented biogeochemical model, Catchment Nutrient Management Model – DeNitrification-DeComposition (CNMM-DNDC), was modified by adding tea-growth-related processes that may induce a soil pH reduction. Using a dataset for intensively managed tea plantations at a subtropical site, the performances of the original and modified models for simulating the emissions of both gases subject to different fertilization alternatives and stand ages were evaluated. Compared with the observations in the early stage of a tea plantation, the original and modified models showed comparable performances for simulating the daily gas fluxes (with a Nash–Sutcliffe index (NSI) of 0.10 versus 0.18 for N2O and 0.32 versus 0.33 for NO), annual emissions (with an NSI of 0.81 versus 0.94 for N2O and 0.92 versus 0.94 for NO) and annual direct emission factors (EF d s). For the modified model, the observations and simulations demonstrated that the short-term replacement of urea with oil cake stimulated N2O emissions by ∼62 % and ∼36 % and mitigated NO emissions by ∼25 % and ∼14 %, respectively. The model simulations resulted in a positive dependence of EF d s of either gas on nitrogen doses, implicating the importance of model-based quantification of this key parameter for inventory purposes. In addition, the modified model with pH-related scientific processes showed overall inhibitory effects on the gases' emissions in the middle to late stages during a full tea plant lifetime. In conclusion, the modified CNMM-DNDC exhibits the potential for quantifying N2O and NO emissions from tea plantations under various conditions. Nevertheless, wider validation is still required for simulation of long-term soil pH variations and emissions of both gases from tea plantations.

Thyroid cancer is the most important malignant tumor reported in human populations where, its treatment remains undeveloped. Fisetin, a plant flavonoid exhibits several pharmacological properties like antioxidant, anti-inflammatory, and anticancer function. In the existing study, we assessed fisetin mediated cytotoxic effects and action potential of fisetin on cell proliferation in TPC-1 human cancer cells. Also, examined the apoptosis in TPC-1 cells by reactive oxygen species (ROS) generation, the mitochondrial membrane potential (MMP) and apoptotic morphological changes through AO/EtBr staining. Additionally, we analyzed the effects of fisetin through ELISA analysis to evaluate the caspases expression and studied JAK 1 and STAT3 signaling molecule in TPC1 cells. Our results demonstrated that fisetin stimulated apoptosis, which confirmed through reduced cell viability, improved ROS generation, altered MMP and cell cycle phases in TPC-1 cells. Further, the fisetin up-regulated the expression of caspase (3, 8, and 9) expressions in TPC-1 cells. Also, we observed the fisetin down-regulated the JAK 1 and STAT3 expression in TPC1 cells. Thus, the fisetin induced apoptosis in TPC-1 cells by the induction of oxidative damage and enhanced caspases expression by down-regulating JAK 1 and STAT3 signaling molecules. Hence, the fisetin would be considered as a beneficial therapeutic agent for the thyroid cancer treatment.

Permeation accompanying droplet spreading is a well-known phenomenon in additive manufacturing, for example in inkjet printing and coating, where the extremely dynamic evolution of the free surface influences printing accuracy and uniformity. It is exceedingly difficult to track the permeation interface and dynamically deformed surface by experimental methods alone. In the work reported here, we adopted a meshless computational method to investigate the dynamic behavior of the permeable fluid passing through a T-shaped junction to elucidate the permeation phenomenon. Four permeation modes—retraction, suspension or capture (SOC), asymmetric transverse penetration (ATP), and symmetrical transverse penetration (STP)—have been studied under different forces and wettability. Regime maps between the Weber number and the wetting conditions are presented to reveal the mechanisms of the permeation modes and the transitions from one to another. The retraction pattern that dominates the permeation behavior on a hydrophobic substrate is already well known (and called the Cassie–Baxter state). For the hydrophilic condition, the permeation pattern is determined by the ratio of the inertia force to the capillary force. The SOC, ATP, and STP modes emerge sequentially as the inertia force rises. The ATP mode occurs when the maximal amplitude of the meniscus interface reaches the bottom wall, and the STP mode depends on the inertia force overcoming the capillary force. These two permeation mechanisms result in different tendencies of mode transition. A porous model of arrayed T-junctions is also presented to investigate the combined process of permeation and spreading. It is found that various combinations of permeation modes during droplet spreading play an important role in the permeation dynamics, and that inhibition of transverse creeping enhances the spreading on a highly porous substrate.

Ornithine decarboxylase (ODC) plays an important role in various biological processes; however, its role in plant secondary metabolism, especially in the biosynthesis of tropane alkaloids (TAs) suc...

Planar perovskite solar cells (PSCs) have the potential to compete with mesoporous PSCs due to their comparable power conversion efficiency (PCE) and their preparation, which can be achieved via similar processes to those of flexible or tandem PSCs. However, the severe current–voltage hysteresis that occurs in PSCs is still a big issue, attributable to trap-induced charge recombination and ion migration. Herein, we develop a universal strategy combining interface (PMMA:C60) and grain boundary (PTABr) engineering to effectively eliminate the hysteresis of planar PSCs by finely tuning the electron transport layer/perovskite interface and perovskite film morphology (grain size and grain boundary). Microstructure and spectral characterization, density functional theory (DFT) calculations and photoelectric measurements reveal that this ingenious combination of the two engineering approaches effectively reduces the trap sites and enlarges the perovskite grain size, leading to negligible hysteresis and high performance PSCs based on various compositional perovskites including MAPbI3, Cs0.15FA0.85PbI3 and Cs0.15FA0.75MA0.1PbI3, with power conversion efficiencies (PCEs) of 18.99%, 19.82%, 21.41% and extra-low hysteresis indices of 0.011, 0.007, 0.005, respectively. This work demonstrates a universal strategy by which to fabricate high efficiency and negligible hysteresis PSCs regardless of perovskite composition.

We report here a new technique for the identification and visualization of functional domains in stratified metal–organic frameworks (MOFs). The technique, namely, gold diffusion enabled domain identification, utilizes the diffusion of Au nanoparticles within MOF cavities to track and selectively stain the more Au-philic domain in an MOF particle thereby allowing direct observation of domains, determination of domain sequences, and, in certain cases, domain boundaries under transmission electron microscopy. This method is an excellent tool for studying MOF materials with complex domain hierarchy., We report a new technique for the identification and visualization of functional domains in stratified metal−organic frameworks.

Gene promoter hypermethylation is a vital step in tumorigenesis. This paper set out to explore the use of polymerase chain reaction - surface-enhanced Raman spectroscopy (PCR-SERS) for the detection of gene methylation levels, with a focus on cancer diagnosis. Methods: PCR with methylation independent primers were used on DNA samples to amplify target genes regardless of their methylation states. SERS was used on the obtained PCR products to generate spectra that contained peak changes belonging to CG and AT base pairs. Multiple linear regression (MLR) was then used to deconvolute the SERS spectra so that the CG/AT ratios of the sample could be obtained. These MLR results were used to calculate methylation levels of the target genes. For protocol verification, three sets of seven reference DNA solutions with known methylation levels (0%, 1%, 5%, 25%, 50%, 75%, and 100%) were analysed. Clinically, blood plasma samples were taken from 48 non-small-cell lung cancer (NSCLC) patients and 51 healthy controls. The methylation levels of the genes p16, MGMT, and RASSF1 were determined for each patient using this method. Results: Verification experiment on the mixtures with known methylation levels resulted in an error of less than 6% from the actual levels. When applied to our clinical samples, the frequency of methylation in at least one of the three target genes among the NSCLC patients was 87.5%, but this percentage decreased to 11.8% for the control group. The methylation levels of p16 were found to be significantly higher in NSCLC patients with more pack-years smoked (p=0.04), later cancer stages (p=0.03), and cancer types of squamous cell and large cell versus adenocarcinoma (p=0.03). Prediction accuracy of 88% was achieved from classification and regression trees (CART) based on methylation levels and states, respectively. Conclusion: This research showed that the PCR-SERS protocol could quantitatively measure the methylation levels of genes in plasma. The methylation levels of the genes p16, MGMT, and RASSF1 were higher in NSCLC patients than in controls.

Co-infection of maize chlorotic mottle virus (MCMV) with a virus in the Potyviridae family, such as sugarcane mosaic virus, usually leads to maize lethal necrosis (MLN). Over the past decade, MCMV/MLN has emerged in many countries/regions of the world and resulted in serious yield loss in maize production. Although partial functions of some MCMV-encoded proteins have been identified, the host factors related to MCMV replication are poorly understood. Here, we show that maize peroxisomes can form aggregated bodies in MCMV-infected leaf cells. The dsRNA binding-dependent fluorescence complementation assay indicated that the aggregated peroxisomes in maize served as the major replication site of MCMV. In addition, our results revealed that all the three maize catalases were present mostly in peroxisomes in the presence or absence of MCMV. Furthermore, we determined that inhibition of catalase activity or induction of reactive oxygen species (ROS) in maize protoplasts significantly reduced the accumulation of MCMV RNA. In summary, this research reveals the replication site of MCMV and an important role of maize catalases in supporting virus replication. Our results are conducive to understanding the pathogenesis of MCMV and identifying targets for resistance breeding or gene regulation strategies.

Nanozymes are one of the ideal alternatives to natural enzymes for various applications. The rational design of nanozymes with improved catalytic activity stimulates increasing attention to address the low activity of current nanozymes. Here, we reported a general strategy to fabricate the Co-based homobimetallic hollow nanocages (HNCs) (C-CoM-HNC, M = Ni, Mn, Cu, and Zn) by ion-assistant solvothermal reaction and subsequent low-temperature calcination from metal-organic frameworks. The C-CoM-HNCs are featured with HNCs composed of interlaced nanosheets with homogeneous bimetallic oxide dispersion. The hierarchical structure and secondary metallic doping endow the C-CoM-HNC highly active sites. In particular, the Cu-doped C-CoCu-HNCs nanostructures exhibit superior performances over the other C-CoM-HNC as both the oxidase mimicking and peroxymonosulfate (PMS) activator. A sensitive bioassay for acetylcholinesterase (AChE) was established based on the excellent oxidase-like activity of C-CoCu-HNC, offering a linear detection range from 0.0001 to 1 mU/mL with an ultralow detection limit of 0.1 mU/L. As the PMS activator, the C-CoCu-HNC was applied for targeted organic pollutant (rhodamine B, RhB) degradation. A highly efficient RhB degradation was realized, along with good adaptability in a wide pH range and good reusability during the eight-cycle run. The results suggest that C-CoCu-HNC holds a practical potential for clinical diagnostics and pollution removal. Further density functional theory calculation reveals that Cu doping leads to a tighter connection and more negative adsorption energy for O2/PMS, as well as an upshifted d-band center in the C-CoCu-HNCs nanostructures. These changes facilitated the adsorption of O2/PMS on the C-CoCu-HNC surface for dissociation. This work not only offers a promising multifunctional nanozyme catalyst for clinical diagnostics and pollution removal but also gives some clues for the further development of novel nanozymes with high catalytic activities.

The amorphous I/Au composite nanoflms were prepared by low vacuum direct current sputtering (LVDCS) method. The optimized preparation technologies contain growth pressure, time, gaseous environment and annealing conditions. The maximum fuorescence emission (λemmax) of I/Au nanoflms was observed at wavelength of 375 nm, and the intensity of fuorescence emission peak of annealed I/Au flms was smaller than that of unannealed one due to fewer amorphous Au nanoparticles, caused by annealing treatment. In the UV-Vis absorption spectra, the intensity of UV-Vis absorption peak of annealed I/ Au nanoflms is larger than that of the unannealed one. This work also developed a new way to grow I/Au composite fuorescent thin flms.

There are still a number of challenges to be addressed for the harmonic vibro-impacting drilling technology to become the norm in the industry. The change mechanism of energy response of rock under harmonic vibro-impacting is one of the problems that needs to be solved, which is also an indispensable part of the rock-breaking mechanism of the technology. Thus, this study focuses on the modelling of energy response of rock under harmonic vibro-impacting. Modelling of energy response of rock with and without damping under harmonic vibro-impacting is undertaken and the corresponding equations of energy dissipation are presented in this study. Subsequently, the results of numerical calculation are given and the effects of natural frequency of rock, impacting frequency, impacting force and other parameters of energy response of rock are analyzed. Finally, a practical case is given to demonstrate the rock-breaking effect under harmonic vibro-impacting drilling. The results show that energy response of rock with damping decays regularly over time in the harmonic form under harmonic vibro-impacting. Also, it increases with the increase of natural frequency and mass of rock, impacting frequency and force, and is not affected by the stiffness of the rock. In addition, the penetration rate in practice has been greatly improved under harmonic vibro-impacting. Based on the analysis undertaken, the variation mechanism of energy response of rock under harmonic vibro-impacting was found and the rock-breaking effect of the technology was verified. The study on the modelling of energy response of rock under harmonic vibro-impacting can provide a theoretical basis for applying harmonic vibro-impacting drilling technology.

The quality of medicinal plants is closely related to the ecological factors in growing locations, and the curative ingredients and biopotency reflect their quality. This study determined the active ingredient concentrations (tenuifolin, polygalaxanthone III, 3,6′-disinapoyl sucrose, sibiricose A5, sibiricose A6 and sibiricaxanthone B) and biopotency (intelligence, tranquilisation and expectorant) of Polygala tenuifolia Willd. from the main cultivation regions of China. Moreover, this study discussed how 36 ecological factors (e.g. climate and soil condition) influenced these ingredients and their biopotency. The relationship between ecological factors and quality factors was analyzed step by step using correlation analysis, principal component analysis and path analysis. Nine ecological factors: annual mean temperature, annual sunshine duration, soil pH, Cl, Sr, Ca, S, B and exchangeable K concentration were considered as key factors that influenced the quality of cultivated P. tenuifolia. This study provided a novel approach for the quality evaluation of P. tenuifolia and a rational pattern for exploring the complex relationship between ecological factors and P. tenuifolia quality.

Shale gas plays an important role in energy transformation. The sustainable development of the shale gas industry is a prerequisite for achieving an efficient, green, and long-term use of shale gas resources. This paper uses the WSR (Wuli-Shili-Renli) methodology to determine a comprehensive indicator system for assessing the sustainability of the shale gas industry. Game theory was used to combine two objective weighting methods and determine the comprehensive weight. The sustainability of the shale gas industry was evaluated based on the fuzzy matter-element extension theory. The results of the evaluation show that the overall sustainable development of China’s shale gas industry is relatively poor. Shale gas industry in most regions is in a critically sustainable state (The critically sustainable state indicates the sustainability of the shale gas industry in general. The industry as a whole has the basic conditions for sustainable development in the short term; however, efficiency needs to be further improved to avoid the risk of degradation.) and is susceptible to degradation due to environmental changes. The shale gas industry in a few other regions is in an unsustainable state and cannot achieve an efficient and green development of shale gas. This paper evaluated the sustainability of the shale gas industry from a unique perspective. It is expected that the results of this research will contribute to the formulation of sustainable development strategies and further promote the green development of the shale gas industry.

The development of room temperature NH3 sensors with flexible substrate can fulfill the future demands of high NH3 sensing performance under the premise of lower energy consumption and safety circumstance in wearable electronics field. The polyaniline and a serious of WO3 hollow spheres@ polyaniline hybrid were successfully synthesized via a combined route of simple hydrothermal method and in-situ chemical oxidative polymerization. The room temperature NH3 sensors were fabricated by assembling WO3 hollow spheres@ polyaniline hybrid on flexible polyethylene terephthalate (PET) films. The NH3 sensing properties of the fabricated devices demonstrated that the device utilizing 10 mol% WO3 hollow spheres@ polyaniline (PAWHs 10) hybrid exhibited the best sensing performance to 100 ppm NH3 (response value at 25) at 20 °C. Moreover, the PAWHs10 hybrid sensor also achieved excellent NH3 selectivity, ppb-level detection limit (1.67–500 ppb NH3), and good response/recovery rates (136 s/130 s) at 20 °C. The enhanced sensing performance of incorporation of polyaniline and WO3 hollow spheres was mainly attributed to the hollow structure of WO3 and the formation of p-n heterojunction between PANI and WO3 hollow spheres.

Developing photocatalysts capable of organic oxidations enables the generation of value-added products from biomass feedstocks through visible light irradiation. Through a series of nonaqueous phot...

In this work, we developed a high-response mixed potential type yttria stabilized zirconia (YSZ) based planar gas sensing device utilizing CoTiO3 sensing electrode (SE) prepared via a facile sol-gel method to sensitively detect NO2 at an operating temperature of 650 °C. The present gas sensor coupled with 1200 ℃-sintered CoTiO3-SE exhibited high responses to NO2 in the concentration range of 500 ppb-200 ppm, as the value of the response was 130 mV to 100 ppm NO2. A linear relationship was observed between the ΔV of the sensor and the logarithmic scale of the NO2 concentration, which the sensitivity was 60 mV/decade. In addition, the sensor also displayed good reproducibility, the maximum response change of 5.4% and 16% in different coexisting gases and 98% high relative humidity, and response decrease of 6.9%–100 ppm NO2 after high temperature test for 20 days. Moreover, the sensing mechanism of sensor, which was based on mixed potential model, was confirmed using polarization curve measurements in air and different concentrations of NO2.

Ti3C2T x MXene with an organ-like structure was synthesized from Ti3AlC2 (MAX phase) through the typical hydrofluoric (HF) acid etching method. Ti3C2T x MXene was further alkaline-treated with a sodium hydroxide solution to obtain alkalized Ti3C2T x. Room-temperature planar-type gas- and humidity-sensing devices were also fabricated by utilizing Ti3C2T x MXene and alkalized Ti3C2T x sensing material based on the dip coating method, respectively. The intercalation of the alkali metal ion (Na+) and the increase of the surface terminal oxygen-fluorine ratio ([O]/[F]) in Ti3C2T x can effectively improve humidity- and gas-sensing properties at room temperature. The developed alkalized Ti3C2T x sensor exhibited excellent humidity-sensing characteristics (approximately 60 times response signal change) in the relative humidity (RH) with a range of 11-95% and considerable NH3 sensing performance (28.87% response value to 100 ppm of NH3) at room temperature. The improvement of NH3 and humidity-sensing properties indicated that alkalized Ti3C2T x has great potential in chemical sensors, especially in NH3 and humidity sensors.

Urea accounts for over half of the global ammonia volatilization from synthetic nitrogen fertilization. Process-oriented models, such as the widely applied DeNitrification DeComposition 9.5 version (DNDC95), are expected to predict ammonia volatilization from agricultural urea applications under various conditions. However, compared to the wind-tunnel ammonia observations of a nationwide, seven-site/ten-case network in the United Kingdom, the DNDC95 greatly underestimated the ammonia volatilization from winter cereal fields applied with urea at a constant dose. The model was revised in this study mainly through (i) newly parameterizing the effects of clay fraction, plant standings and canopy wetting on ammonia release from the soil solution, and (ii) re-calibrating the parameters of the urea hydrolysis function and the original parameterizations of wind, soil temperature and moisture effects on ammonia volatilization using the observations in one case of the network. Next, the performances of the revised model (DNDC95_NH3) in simulating grain yield, full crop nitrogen uptake, cumulative ammonia volatilization (CAV) and daily ammonia fluxes were evaluated using the observations of these variables in the other nine network cases. The DNDC95_NH3 performed considerably better than the DNDC95. Particularly, the slopes of the zero-intercept regression for the observations versus simulations decreased from 1.97 to 0.86 and 1.65 to 0.75 for the CAV and daily ammonia fluxes, respectively. In addition, the number of the cases with significant discrepancies between simulated and observed CAV was reduced from six of the nine network cases to only two. The simulations by the revised model for these two cases showed a significant underestimation and an extremely large overestimation, respectively. However, reasons especially for the significant overestimation still remain unclear. Future studies still need to diagnose and solve the other existing problems so as to further improve the model's performance.

Simulation of ammonia (NH3) volatilization by process-oriented biogeochemical models, such as the widely used DeNitrification DeComposition (DNDC), is an imperative need to identify the best management strategies that can improve nitrogen use efficiency in crop production while alleviating environmental pollution. However, scarce validation has been impeding the applicability of the DNDC for this purpose. Using the micrometeorological or wind tunnel-based observations of NH3 volatilization in 44 cases with at seven nationwide field sites in China, which were cultivated with summer maize and winter wheat in calcareous soils and applied with synthetic fertilizers, the DNDC was tested, modified, and evaluated in this study. The following major modifications were made in the model source codes. Primarily, pedo-transfer functions were introduced into the model to provide three soil hydraulic parameters that are required to simulate soil moisture. Then, the temperature effect on ammonium bicarbonate decomposition, which was originally missing, was parameterized. Finally, the effect of soil texture on ammonia volatilization from the liquid phase was re-parameterized while an adaption factor was set. Seven typical cases were involved in the model modifications and the other 37 independent cases were used for the modified model evaluation. Compared to the original model, the modified DNDC performed better. For instance, it showed a higher index of agreement of 0.77 versus 0.38, a higher modeling efficiency (Nash-Sutcliffe index) of 0.19 versus −0.52, and a greater determination coefficient (R2) of 0.35 (p

The synthesis of ionic liquids (ILs), based on the trimethyl-isobuty-ammonium cation, (N111i4)+, and, respectively, the bis(trifluoromethylsulfonyl)imide (TFSI), (fluorosulfonyl) (trifluoromethylsulfonyl)imide (FTFSI), and bis(fluorosulfonyl)imide (FSI) anions is herein reported. The NMR validation of the N111i4Br precursor as well as the ionic liquids is shown. The thermal properties were investigated via variable-temperature, coupled with mass spectroscopy, and isothermal thermo-gravimetrical analyses, and long-thermal tests. The TFSI-based IL exhibits a melting point of 29.93 °C, which is found to be shifted down to −0.12 and −14.32 °C for the FSI- and FTFSI-based samples, respectively. Additionally, the TFSI- and FTFSI-based samples are able to keep in super cooled state for more than one year. The investigated N111i4-based ionic liquids display an electrochemical stability window exceeding 5.5 V.

Currently, 2D layered materials-derived 0D quantum dots can be applied in many fields due to their fantastic properties. In our work, we initially prepared WTe2QDs and combined them with NiSe/C nanowires (WTe2 QDs-doped NiSe/C) by electrospinning method and high temperature selenization process. The WTe2QDs-doped NiSe/C composite structures were flexible and free-standing, which can be used as electrode directly assembled into Li-ion battery. It displays a great reversible lithium storage ability (with ∼620 mAh g−1 at the current density of 1 A/g over 500 cycles) and good rate capability. Our cyclic voltammetry characterization reveals the redox reaction behavior and structural change of the WTe2QDs-doped NiSe/C nanowires in charge and discharge process.

In this work, the highly selective and stable mixed potential type stabilized zirconia (YSZ) based gas sensor using Cd2V2O7 sensing electrode (SE) synthesized via simple coprecipitation method was fabricated and developed for effective detection of NH3 at 650 °C. The as-prepared Cd2V2O7 sensing material was characterized by X-ray diffraction (XRD), Raman spectrum, X-ray photoelectron spectroscopy (XPS) and Field-emission scanning electron microscopy (FESEM). The results of gas sensing measurement indicated that the sensor attached with Cd2V2O7- SE displayed the response value of −68 mV and rapid response rate of 5 s to 100 ppm NH3 at 650 °C. The present device also exhibited the low detection limit of 1 ppm and the piecewise sensitivities of −6 and −66 mV/decade to NH3 in the concentration ranges of 1–10 ppm and 10–200 ppm, respectively. Moreover, the fabricated sensor showed good reproducibility, excellent selectivity, stability to oxygen concentration, relative humidity and 30 days continuous aging of high temperature at 650 °C. And the complex impedance and polarization curves were performed to explain the selectivity and verify the sensing mechanism involving mixed potential model.

Frequency diverse array (FDA)-multiple-input and multiple-output (MIMO) radar can form angle-distance 2D beam pattern, which has good anti-jamming ability. This paper proposes a towed jamming suppression method based on FDA-MIMO radar. The minimum variance spectral estimation (MVSE) algorithm is used to accurately locate the target and the jamming location, and then the target and the jamming are identified based on the difference in Doppler frequency. Finally, the minimum variance distortionless response (MVDR) adaptive beamforming algorithm suppresses jamming. In addition, this paper selects the square frequency increment instead of the commonly used linear frequency increment, so that the beam has a better range resolution to obtain a better anti-jamming effect. The simulation results prove the effectiveness of the method proposed in this paper.

Background A local coronavirus disease 2019 (COVID-19) case confirmed on June 11, 2020 triggered an outbreak in Beijing, China after 56 consecutive days without a newly confirmed case. Non-pharmaceutical interventions (NPIs) were used to contain the source in Xinfadi (XFD) market. To rapidly control the outbreak, both traditional and newly introduced NPIs including large-scale management of high-risk populations and expanded severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) PCR-based screening in the general population were conducted in Beijing. We aimed to assess the effectiveness of the response to the COVID-19 outbreak in Beijing’s XFD market and inform future response efforts of resurgence across regions. Methods A modified susceptible–exposed–infectious–recovered (SEIR) model was developed and applied to evaluate a range of different scenarios from the public health perspective. Two outcomes were measured: magnitude of transmission (i.e., number of cases in the outbreak) and endpoint of transmission (i.e., date of containment). The outcomes of scenario evaluations were presented relative to the reality case (i.e., 368 cases in 34 days) with 95% Confidence Interval (CI). Results Our results indicated that a 3 to 14 day delay in the identification of XFD as the infection source and initiation of NPIs would have caused a 3 to 28-fold increase in total case number (31–77 day delay in containment). A failure to implement the quarantine scheme employed in the XFD outbreak for defined key population would have caused a fivefold greater number of cases (73 day delay in containment). Similarly, failure to implement the quarantine plan executed in the XFD outbreak for close contacts would have caused twofold greater transmission (44 day delay in containment). Finally, failure to implement expanded nucleic acid screening in the general population would have yielded 1.6-fold greater transmission and a 32 day delay to containment. Conclusions This study informs new evidence that in form the selection of NPI to use as countermeasures in response to a COVID-19 outbreak and optimal timing of their implementation. The evidence provided by this study should inform responses to future outbreaks of COVID-19 and future infectious disease outbreak preparedness efforts in China and elsewhere. Graphical abstract

A kind of novel three-dimensionally ordered macroporous molecularly imprinted microspheres (3DMIMs) had been developed for selective recognition and separation of quinine based on the combination of colloidal crystal templating method and molecular imprinting technique. The 3DMIMs were derived from the spherical silica colloidal crystal involving a four-step templating process including infiltration of imprinted precursors, sealing of polyethylene glycol, initiation polymerization, as well as final removal of the colloidal crystal and imprinting template. The resulted 3DMIMs consisted of a three-dimensional, highly ordered and interconnected macroporous arrays with nanoscale thickness of polymer wall, in which numerous imprinted cavities were obtained. The kinetic and isothermal adsorption behavior of the 3DMIMs were investigated in detail. The results showed the 3DMIMs had a rapider mass transfer process, higher adsorption capacities and recognition specificity toward quinine compared with the traditional bulk imprinted polymers. In addition, the 3DMIMs exhibited obvious high permeability and low backpressure at high flow rate as column packing. Extraction experiments showed that the 3DMIMs could effectively separate quinine and its diastereoisomer, quinidine, directly from crude cinchona bark extract with a satisfactory selectivity and elution recovery.

Herein, we reported the design and fabrication of polyoxometalates coupling metal-organic framework (POM@MOF) hybrids derived hierarchical hollow Mo/Co bimetal oxides nanocages (Mo/Co HHBONs) for the peroxymonosulfate (PMS) activation to degrade levofloxacin (Lev). The Mo/Co HHBONs are hollow nanocages with high specific-surface areas and hierarchical micropores, mesopores, and macropores. In addition to compositional modulation, polyoxometalate (H3PMo12O40·nH2O) exhibited striking effect on the textural properties of Mo/Co HHBONs. The Mo/Co HHBONs had outstanding catalytic activity with first order-kinetics that were 6 − 10 times higher those previously reported. They exhibited good adaptability over a pH range of 3 − 11, as well as excellent universality and reusability. By altering the surface porosity, electronic structure, and oxygen vacancies of Co3O4, hetero-metal Mo doping induced Mo/Co HHBONs significantly promote the generation of reactive oxygen species, including •OH, SO4•−, O2•−, and 1O2. Density functional theory indicated that Mo/Co HHBONs had better adsorption, enhanced electron-transfer abilities, and a longer O-O bond length than did Co3O4, for improved catalytic reactivity. This research provides a new strategy to design the POM@MOF hybrids derived hierarchical hollow nanocages with highly PMS activating capacity for the removal of antibiotics and other refractory contaminants.

We report the demonstration of optical compression of an electron beam and the production of controllable trains of femtosecond, soft x-ray pulses with the Linac Coherent Light Source (LCLS) free-electron laser (FEL). This is achieved by enhanced self-amplified spontaneous emission with a 2 μm laser and a dechirper device. Optical compression was achieved by modulating the energy of an electron beam with the laser and then compressing with a chicane, resulting in high current spikes on the beam which we observe to lase. A dechirper was then used to selectively control the lasing region of the electron beam. Field autocorrelation measurements indicate a train of pulses, and we find that the number of pulses within the train can be controlled (from 1 to 5 pulses) by varying the dechirper position and undulator taper. These results are a step toward attosecond spectroscopy with x-ray FELs as well as future FEL schemes relying on optical compression of an electron beam.

Clusteroluminescence is a phenomenon whereby the aggregation or clustering of non-conjugated electron-rich units leads to the emission of light at long wavelengths. This phenomenon was first discovered in poly(amido amine) (PAMAM) dendrimers. In recent years, clusteroluminescence has attracted growing research interest and its photophysical properties and mechanism have been thoroughly studied. In this review, we first briefly introduce the development of different types of clusteroluminogens. Then we highlight recent developments in clusteroluminescence, including mechanistic studies, the disclosure of room-temperature phosphorescence, and the extension of emission to the longer-wavelength region. Lastly, we demonstrate a few applications in various fields. With advantages such as being earth-abundant, biocompatible and biodegradable, clusteroluminogens are envisioned to be commonplace in the future.

The electrocaloric effect (ECE) in dielectrics is characterized by the isothermal entropy change ΔS and adiabatic temperature change ΔT induced by changes of external electric fields. The Maxwell relation, which relates changes of polarization P with temperature T (pyroelectric coefficient) under a fixed electric field E to ΔS for finite intervals in E, provides a convenient way to deduce the ECE from polarization data P(T, E). Hence, this method, known as the indirect method, is widely used in ECE studies in ferroelectrics. Here, we first present the thermodynamic consideration for the Maxwell relation. We then use the indirect method and P(T, E) from bipolar and unipolar polarization curves to deduce the ECE in the normal ferroelectric phase of a P(VDF-TrFE) copolymer. The deduced ECE using the P(T, E) from bipolar polarization curves exhibits a giant negative ECE. In contrast, the directly measured ECE in the same polymer shows the weak and normal ECE. We discuss the constraints of the indirect method and its relation to the polarization–electric field curves measured in practical ferroelectric materials.

The possibility of suddenly ionized molecules undergoing extremely fast electron hole (or hole) dynamics prior to significant structural change was first recognized more than 20 years ago and termed charge migration. The accurate probing of ultrafast electron hole dynamics requires measurements that have both sufficient temporal resolution and can detect the localization of a specific hole within the molecule. We report an investigation of the dynamics of inner valence hole states in isopropanol where we use an x-ray pump-x-ray probe experiment, with site and state-specific probing of a transient hole state localized near the oxygen atom in the molecule, together with an ab initio theoretical treatment. We record the signature of transient hole dynamics and make the first tentative observation of dynamics driven by frustrated Auger-Meitner transitions. We verify that the effective hole lifetime is consistent with our theoretical prediction. This state-specific measurement paves the way to widespread application for observations of transient hole dynamics localized in space and time in molecules and thus to charge transfer phenomena that are fundamental in chemical and material physics. (Less)

There are more and more researches on joint relation extraction, however, the current popular joint extraction method has more or less limitations, either the training time is too long or the effect is not very good. In this paper, we propose an end-to-end relation extraction model, without using handcraft features, and propose a novel graph convolutional neural network based on entity attention mechanism which can perform better feature extraction on tree nodes. In addition, for preserving relevant information on the dependency tree to the greatest extent, we use a path-centric pruning strategy to remove irrelevant content, it makes the model more robust. Our model consists of five parts: Bert layer for vector representation, BiGRU layer, CRF layer for sequence labeling, GCN layer and Predict layer. To evaluate our method, we conduct experiments on the public dataset NYT and ACE05. Our model achieve the state of the art on the task of entity and relation extraction.

Direct observation of nanoparticle adsorption to the water-oil interface captures early attachment and jamming., Electrostatic interactions between nanoparticles (NPs) and functionalized ligands lead to the formation of NP surfactants (NPSs) that assemble at the water-oil interface and form jammed structures. To understand the interfacial behavior of NPSs, it is necessary to understand the mechanism by which the NPSs attach to the interface and how this attachment depends on the areal coverage of the interface. Through direct observation with high spatial and temporal resolution, using laser scanning confocal microscopy and in situ atomic force microscopy (AFM), we observe that early-stage attachment of NPs to the interface is diffusion limited and with increasing areal density of the NPSs, further attachment requires cooperative displacement of the previously assembled NPSs both laterally and vertically. The unprecedented detail provided by in situ AFM reveals the complex mechanism of attachment and the deeply nonequilibrium nature of the assembly.

X-ray photoelectron spectroscopy (XPS) measures the binding energy of core-level electrons, which are well-localised to specific atomic sites in a molecular system, providing valuable information on the local chemical environment. The technique relies on measuring the photoelectron spectrum upon x-ray photoionisation, and the resolution is often limited by the bandwidth of the ionising x-ray pulse. This is particularly problematic for time-resolved XPS, where the desired time resolution enforces a fundamental lower limit on the bandwidth of the x-ray source. In this work, we report a novel correlation analysis which exploits the correlation between the x-ray and photoelectron spectra to improve the resolution of XPS measurements. We show that with this correlation-based spectral-domain ghost imaging method we can achieve sub-bandwidth resolution in XPS measurements. This analysis method enables XPS for sources with large bandwidth or spectral jitter, previously considered unfeasible for XPS measurements.

Author Posting. © American Geophysical Union, 2020. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 125(11), (2020): e2019JC015851, doi:10.1029/2019JC015851.

Reservoirs are regarded as hotspots of nitrogen transformation and potential sources of nitrous oxide (N2O). However, it remains unclear how the hydrological conditions due to dam construction control the processes of nitrogen transformation in reservoir waters. To address this issue, we examined the spatial-temporal characteristics of nitrate concentrations, δ15N-NO3-, δ18O-NO3-, δ18O-H2O, relative water column stability (RWCS), and related environmental factors in a subtropical eutrophic reservoir (Hongfeng Reservoir, HFR), Southwest China. We found that denitrification was the most important nitrogen transformation process in the HFR and that higher denitrification intensity was associated with increased RWCS in summer, which suggested hydrological control of the denitrification process. In contrast, low RWCS conditions favored the nitrification process in the HFR in winter. Additionally, dissolved oxygen (DO; p