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Color centers in silicon carbide (SiC) offer exciting possibilities for quantum information processing. However, the challenge of ionization during optical manipulation leads to charge variations, hampering the efficacy of spin-photon interfaces. Recent research predicted that modified divacancy color centers can stabilize their charge states, resisting photoionization. This study presents a method for precisely creating single divacancy arrays in 4H-SiC using a focused helium ion beam. Photoluminescence tests reveal consistent emission with minimal linewidth fluctuations (∼50 MHz over 3 h). By measuring the ionization rate for different polytypes of divacancies, we found that the modified divacancies are more robust against resonant excitation. Furthermore, angle-resolved photoluminescence excitation spectra unveil two resonant-transition lines with orthogonal polarizations. Enhanced optical and spin characteristics were notably observed in these color centers compared to those generated through carbon-ion and shallow implantation methods, positioning modified divacancies as promising contenders for advancing quantum networking. Divacancy color centers in SiC are promising candidates for a spin-photon interface, but typically show charge-state instability under optical excitation. Here the authors show that modified divacancies created by a focused helium ion beam are robust against photoionization and have promising properties. [ABSTRACT FROM AUTHOR]

Twelve compounds, including eleven bisabolane-type sesquiterpenoids (1 − 11), and one bacillibactin (12) were identified from marine-derived fungus Aspergillus sydowii SCSIO 41041 isolated from Creseis acicula. The chemical structures were elucidated by the basis of spectroscopic evidences, including HRESIMS, NMR and optical rotation. Biologically, all compounds were evaluated for their acetyl cholin-esterase (AChE) enzyme, pancreatic lipase (PL) enzyme, neuraminidase (NA) and phosphodiesterase 4 (PDE4) inhibitory activities. Compound 12 displayed significant inhibitory activity against neuraminidase (NA) with an IC50 value of 24.0 μM, which was equivalent to the positive drug oseltamivir phosphate (IC50 value of 20.0 μM). And the NA inhibitory activity was confirmed by molecular docking analysis. [ABSTRACT FROM AUTHOR]

Context. The origins of lenticular galaxies (S0s) can be classified into two main categories: "minor mergers" in low-density environments (LDEs) and "faded spirals" in high-density environments (HDEs). The transitional phase in the evolution of S0s, namely, star-forming lenticular galaxies (SFS0s), can serve as an important probe for analyzing the complex processes involved in the transformation between different galaxy types and the quenching of star formation (SF). Aims. We attempt to find the impact of different environments on the global properties and spatially resolved quantities of SFS0s. Methods. We selected 71 SFS0s from the SDSS-IV MaNGA Survey, comprising 23 SFS0s in HDEs (SFS0s_HE) and 48 SFS0s in LDEs (SFS0s_LE). We examined the effects of the environment, by studying the global properties, concentration index, and radial profiles of the derived quantities. Results. The varied environments of SFS0s do not lead to any significant difference in global properties (e.g., Sérsic index). By calculating CIHα/cont, we observe that different environments may cause varying concentrations of SF. Specifically, SFS0s_LE, affected by external gas mergers or inflow, exhibit a more centrally concentrated SF (i.e., larger CIHα/cont). This trend is further supported by CISFR, Hα, which only considers the gas disk of the galaxy. This observation is aligned with the observed shrinking of gas disks in galaxies affected by ram-pressure stripping in HDEs. Furthermore, their ΣSFR or resolved sSFR are comparable. On average, SFS0s_LE display significantly higher values for both quantities. Finally, the observed Dn4000 and gas-phase metallicity gradient correspond well to their assumed origins. However, we did not find a significantly lower gas-phase metallicity in SFS0s_LE. Conclusions. We suggest that different environments (i.e., origins) do not have a significant impact on the global properties of SFS0s, but they do indeed affect the distribution of SF. Considering the size of our sample and the unique nature of the galaxy, additional atomic and molecular gas data may provide further details to improve our understanding of these systems. [ABSTRACT FROM AUTHOR]

Acidic stress is a formidable environmental factor that exerts adverse effects on plant growth and development, ultimately leading to a potential reduction in agricultural productivity. A low pH triggers Ca2+ influx across the plasma membrane (PM), eliciting distinct responses under various acidic pH levels. However, the underlying mechanisms by which Arabidopsis plant cells generate stimulus-specific Ca2+ signals in response to acidic stress remain largely unexplored. The experimentally induced stimulus may elicit spikes in cytosolic free Ca2+ concentration ([Ca2+]i) spikes or complex [Ca2+]i oscillations that persist for 20 min over a long-term of 24 h or even several days within the plant cytosol and chloroplast. This study investigated the increase in [Ca2+]i under a gradient of low pH stress ranging from pH 3.0 to 6.0. Notably, the peak of [Ca2+]i elevation was lower at pH 4.0 than at pH 3.0 during the initial 8 h, while other pH levels did not significantly increase [Ca2+]i compared to low acidic stress conditions. Lanthanum chloride (LaCl3) can effectively suppress the influx of [Ca2+]i from the apoplastic to the cytoplasm in plants under acid stress, with no discernible difference in intracellular calcium levels observed in Arabidopsis. Following 8 h of acid treatment in the darkness, the intracellular baseline Ca2+ levels in Arabidopsis were significantly elevated when exposed to low pH stress. A moderately low pH, specifically 4.0, may function as a spatial-temporal input into the circadian clock system. These findings suggest that acid stimulation can exert a continuous influence on intracellular calcium levels, as well as plant growth and development. [ABSTRACT FROM AUTHOR]

This study explores a relationship between the |$\rm {CO}$| luminosity-full width at half-maximum linewidth linear relation (i.e. the |$\rm {CO}$| LFR) and mean galaxy property of the local star-forming galaxy sample in the xCOLDGASS data base, via a mathematical statement. The whole data base galaxies were separated into two subsamples based on their stellar masses and redshifts, being a help to examine the dependence issue of the |$\rm {CO}$| LFR. Selecting the galaxy data with a stringent requirement was also implemented in order to assure the validly of the |$\rm {CO}$| LFR. An algorithm of the linear regression was conducted with the data of the subsample. An assessment about the linear correlation manifested a valid |$\rm {CO}$| LFR occurs in the selected galaxy of the subsample, and the intercept of the |$\rm {CO}$| LFR may be related with the mean galaxy properties such as the molecular gas fraction and galaxy size. For the finding on the intercept of the |$\rm {CO}$| LFR, we aligned that intercept with those galaxy properties via the involvement of a |$\psi$| parameter. On evaluating the |$\psi$| value with our local star-forming galaxy sample, we numerically determined a relationship between the statistical result and the galaxy property in a different stellar mass range. It also shows a possible method on estimating galaxy property. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Staphylococcus aureus is a common pathogenic microorganism in humans and animals. Type II NADH oxidoreductase (NDH-2) is the only NADH:quinone oxidoreductase present in this organism and represents a promising target for the development of anti-staphylococcal drugs. Recently, myricetin, a natural flavonoid from vegetables and fruits, was found to be a potential inhibitor of NDH-2 of S. aureus. The objective of this study was to evaluate the inhibitory properties of myricetin against NDH-2 and its impact on the growth and expression of virulence factors in S. aureus. Results: A screening method was established to identify effective inhibitors of NDH-2, based on heterologously expressed S. aureus NDH-2. Myricetin was found to be an effective inhibitor of NDH-2 with a half maximal inhibitory concentration (IC50) of 2 μM. In silico predictions and enzyme inhibition kinetics further characterized myricetin as a competitive inhibitor of NDH-2 with respect to the substrate menadione (MK). The minimum inhibitory concentrations (MICs) of myricetin against S. aureus strains ranged from 64 to 128 μg/mL. Time–kill assays showed that myricetin was a bactericidal agent against S. aureus. In line with being a competitive inhibitor of the NDH-2 substrate MK, the anti-staphylococcal activity of myricetin was antagonized by MK-4. In addition, myricetin was found to inhibit the gene expression of enterotoxin SeA and reduce the hemolytic activity induced by S. aureus culture on rabbit erythrocytes in a dose-dependent manner. Conclusions: Myricetin was newly discovered to be a competitive inhibitor of S. aureus NDH-2 in relation to the substrate MK. This discovery offers a fresh perspective on the anti-staphylococcal activity of myricetin. [ABSTRACT FROM AUTHOR]

Spirotryprostatin alkaloids, a class of alkaloids with a unique spirocyclic indoledionepiperazine structure, were first extracted from the fermentation broth of Aspergillus fumigatus and have garnered significant attention in the fields of biology and pharmacology. The investigation into the pharmacological potential of this class of alkaloids has unveiled promising applications in drug discovery and development. Notably, certain spirotryprostatin alkaloids have demonstrated remarkable anti-cancer activity, positioning them as potential candidates for anti-tumor drug development. In recent years, organic synthetic chemists have dedicated efforts to devise efficient and viable strategies for the total synthesis of spirotryprostatin alkaloids, aiming to meet the demands within the pharmaceutical domain. The construction of the spiro-C atom within the spirotryprostatin scaffold and the chirality control at the spiro atomic center emerge as pivotal aspects in the synthesis of these compounds. This review categorically delineates the synthesis of spirotryprostatin alkaloids based on the formation mechanism of the spiro-C atom. [ABSTRACT FROM AUTHOR]

When the hydrostatic thrust bearings operate under conditions of high speed and heavy load, the oil film will be strongly sheared and squeezed, which will increase the temperature of the hydrostatic oil film, resulting in uneven deformation of the workbench and tribology in serious cases. The deformation of the friction pair greatly affects the stability of the workbench during operation, and then affects the machining accuracy. Taking the hydrostatic thrust bearings as the research object, the model of hydrostatic thrust bearings was established based on the fluid–thermosolid coupling theory, and the influencing factors of the deformation of the hydrostatic thrust bearings are analyzed using ANSYS Workbench software, and the influencing laws are discussed. Finally, the correctness of the simulation method is verified by experiments. The results show that the larger the lubricating oil viscosity, the greater the deformation of the guide surface and the oil pad. With the increase in the rotation rate, the deformation of the guide surface and the oil pad increases continuously. With the increase in the inlet flow rate, the deformation of the guide surface and the oil pad is continuously reduced. In engineering practice, on the premise of ensuring the bearings capacity, low-viscosity lubricating oil should be used as much as possible, the rotation rate should be lower, or the inlet flow rate should be increased. [ABSTRACT FROM AUTHOR]

Currently, machine learning-based detectors are widely used to handle millions of Android malware, but they often suffer from poor anti-adversarial attack abilities. The research on the adversarial examples generation method of malware is helpful to promote the development of the field of malware detection. The adversarial examples generation technology in the black-box scenario is more in line with the real environment, but the effect is not good compared with the white-box scenario. To solve this problem, this paper proposes a black box malware adversarial examples generation method based on SNGAN, migrating the SNGAN approach to the malware domain from the image domain, adversarial examples are generated by the network of generator and replace detector iterative training, the training process is stabilized by spectral normalization. The proposed method can cheat the machine learning detectors by adding disturbance to the existing malware. Experimental results show that our method can avoid detection effectively from a variety of machine learning classifiers, and the feasibility and portability of the method are verified. [ABSTRACT FROM AUTHOR]

To remediate historically polluted sites before their land-use changes, it is essential to understand the concentration distribution, geochemical fraction, and migratory behavior of As in soil with varied particle sizes for the use of a sieving procedure. This study investigated the amount and percentage of As in soil with different particle sizes (0.25, 0.25–1, and 1–2 mm) as well as its toxicity characteristic in leaching procedure at four previously contaminated sites in the Beijiang River Basin, South China. The results showed that the total As concentration in the collected soils ranged from 70.1 to 402.8 mg/kg, and only a few percent of soil particle samples had As contents below the local risk threshold value of 60 mg/kg. The amorphous hydrous oxide bound, crystalline hydrous oxide bound, and residual fractions (F3–F5) of the geochemical fraction of As in soil of polluted sites accounted for 82.2–95.7% of the total As distribution. However, the concentration of As in non-specifically bound fractions increased with the mass ratio of soil with coarse particle sizes due to the negative correlation of Fe-bearing minerals concentration with the mass ratio of soil with coarse particle size. According to redundancy analysis, soil with coarse particle sizes and non-specifically bound As were mostly responsible for the As concentration in the leachate. These findings confirmed that a sieving process was not suitable for the remediation of soil As at four historically contaminated sites in the Beijiang River Basin due to the high concentration of As in soil and non-negligible environmental risk of labile extractable As in soil with coarse particle size. [ABSTRACT FROM AUTHOR]

Microbes well-adapted to the Arctic Ocean are promising for producing novel compounds, due to their fancy strategies for adaptation and being under-investigated. Two new phenazine alkaloids (1 and 2) and one new phenoxazine (3) were isolated from Nocardiopsis dassonvillei 502F, a strain originally isolated from Arctic deep-sea sediments. AntiSMASH analysis of the genome of Nocardiopsis dassonvillei 502F revealed the presence of 16 putative biosynthetic gene clusters (BGCs), including a phenazine BGC. Most of the isolated compounds were evaluated for their antibacterial, antiallergic, and cytotoxic activities. Among them, compounds 4 and 5 exhibited potent in vitro cytotoxic activities against osteosarcoma cell line 143B with IC50 values 0.16 and 20.0 μM, respectively. Besides, the results of antiallergic activities of compounds 6–8 exhibited inhibitory activities with IC50 values of 10.88 ± 3.05, 38.88 ± 3.29, and 2.44 ± 0.17 μg/mL, respectively (IC50 91.6 μM for the positive control loratadine). [ABSTRACT FROM AUTHOR]

A new furanone analog, (E)-2-(8,9-dihydroxy-6,8-dimethyldec-4-en-2-yl)-met-hylfuran-3(2H)-one (1), together with six known compounds, including two diterpenoids (2 and 3), one butyrolactone (4) and three isocoumarins (5–7), were isolated from a deep-sea fungus, Purpureocillium sp. SCSIO 06693. Among them, compound 1 existed as two tautomeric forms (1a and 1b) differing in configuration of the furan ring. The chemical structures were elucidated by the basis of spectroscopic evidences, including HRESIMS, NMR and optical rotation. Isolated compounds were evaluated for their cytotoxic, antiviral, antibacterial, antioxidant, acetyl cholinesterase (AChE) and pancreatic lipase (PL) enzyme inhibitory activities. Biological evaluation results revealed that compound 4 showed modest antioxidant activity against DPPH with IC50 value of 72.03 μM. In addition, compounds 1–4 exhibited PL enzyme inhibitory activities. [ABSTRACT FROM AUTHOR]

Taking Chinese fir wood from plantation as the research object, three technological parameters including hot-pressing temperature (160, 180, 200 °C), hot-pressing time (20, 30, 40 min) and compression ratio (30%, 40%, 50%) were selected, and the compression densification modification test of Chinese fir was carried out by using the full factor experimental design. Based on the mechanical properties, microscopic morphology and crystallinity of wood, the effects of different processing parameters on wood properties were analyzed, and the densification process parameters of Chinese fir wood were optimized. The results showed that the properties of the densified wood prepared by Chinese fir were better under the technological conditions of hot pressing temperature of 180 °C, compression ratio of 50%, and pressing time of 40 min. The flexural strength, flexural modulus of elasticity, tensile strength, and hardness of the densified Chinese fir were 130.4 MPa, 12 338 MPa, 113.1 MPa and 1 631 N respectively, which increased by 112%, 113%, 44%, and 55% compared to the untreated wood. The scanning electron microscope observation showed that almost all the early wood cells were crushed, and there were regular folds along the direction of the wood ray, while some of the late wood cells were crushed, and most of them kept the original cavity structure. The hardness and elastic modulus of the cell wall of the densified wood were 16.7% and 45.7% higher than that of the untreated wood. The crystallinity of wood after compression treatment increased. The crystallinity of cellulose in the untreated wood and compressed Chinese fir was 46% and 53%, respectively. [ABSTRACT FROM AUTHOR]

This paper uses the principles of polarisation to calculate the Stokes component of the polarisation image. It designs the spatial weighted fusion algorithm, focusing on the research and evaluation of the accuracy and time complexity of the spatial weighted fusion algorithm in the polarisation image fusion processing. The spatial weighted image fusion algorithm is used to fuse the polarisation degree image, the polarisation angle image, and the light intensity image. Finally, the algorithm function is realised through software programming to verify the effect and accuracy of the algorithm. Experimental results show that the spatial weighted fusion algorithm can keep the pixel value of the polarisation source image unchanged, avoid image distortion, artefacts and ringing effects algorithm is stable and efficient, with low time complexity. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (hBN) is a remarkable two-dimensional (2D) material that hosts solid-state spins and has great potential to be used in quantum information applications, including quantum networks. However, in this application, both the optical and spin properties are crucial for single spins but have not yet been discovered simultaneously for hBN spins. Here, we realize an efficient method for arraying and isolating the single defects of hBN and use this method to discover a new spin defect with a high probability of 85%. This single defect exhibits outstanding optical properties and an optically controllable spin, as indicated by the observed significant Rabi oscillation and Hahn echo experiments at room temperature. First principles calculations indicate that complexes of carbon and oxygen dopants may be the origin of the single spin defects. This provides a possibility for further addressing spins that can be optically controlled. Optically active defects in hBN are promising for quantum sensing and information applications, however, coherent control of a single defect has not been achieved so far. By using an efficient method to produce arrays of defects in hBN, Guo et al. isolate a new carbon-related defect and show its coherent control. [ABSTRACT FROM AUTHOR]

We present a sample of 330 blue edge-on low surface brightness galaxies (ELSBGs). To understand the chemical evolution of ELSBGs, we derived the gas-phase abundance and the [ α /Fe] ratio. Compared with star-forming galaxies, ELSBGs show a flatter trend in the mass–metallicity (M *– Z) relation, which suggests that the oxygen abundance enhancement is inefficient. We focused on 77 ELSBGs with H i data and found that the closed-box model cannot explain their gas fraction and metallicity relation, which implies that infall and/or outflow is needed. We derived the [ α /Fe] ratio of normal ELSBG (<109.5 M ⊙) and massive ELSBG (> = 109.5 M ⊙) using single stellar population grids from the MILES stellar library. The mean [ α /Fe] ratios are 0.18 and 0.4 for normal ELSBG and massive ELSBG, respectively. We suggest that the long timescales of star formation and/or metal-rich gas outflow events caused by SNe Ia winds are likely to be responsible for the α -enhancement of massive ELSBGs. [ABSTRACT FROM AUTHOR]

The restoration of mangrove in coastal wetlands of China has been started since the 1990s. However, various pollutants, especially for heavy metals (HMs), contained in wastewater might present a significant risk to mangrove forests during the restoration. In this study, sediments of five typical mangrove wetlands with varying restoration years and management measures in the Greater Bay Area were collected to evaluate the distribution fractions and potential ecological risk of HMs. Cd (0.2–1.6 mg/kg) was found in high concentrations in the exchangeable fraction (37.8–71.5%), whereas Cu (54.2–94.8 mg/kg), Zn (157.6–332.6 mg/kg), Cr (57.7–113.6 mg/kg), Pb (36.5–89.9 mg/kg), and Ni (29.7–69.5 mg/kg) primarily presented in residual fraction (30.8–91.9%). According to the geo-accumulation index (Igeo) analysis, sediment Cd presented a high level of pollution (3 ≤ Igeo ≤ 4), while Zn and Cu were associated with moderately pollution (1 ≤ Igeo ≤ 2). Besides, high ecological risk of Cd was found in sediments of five mangroves, with risk assessment code (RAC) ranging from 45.9 to 84.2. Redundancy analysis revealed that the content of NO3−-N was closely related to that of HMs in sediments and, pH value and NO3−-N concentration affected the distribution of HMs geochemical fractions. High concentration of HMs in QA and NS sampling sites was caused by the formerly pollutants discharge, resulting in these sediments still with a higher HM pollution level after the plant of mangrove for a long period. Fortunately, strict drainage standards for industrial activities in Shenzhen significantly availed for decreasing HMs contents in mangrove sediments. Therefore, future works on mangrove conversion and restoration should be linked to the water purification in the GBA. [ABSTRACT FROM AUTHOR]

A new glyoxylate-containing benzene derivative, methyl 2-(4-hydroxy-3-(3′-methyl-2′-butenyl)phenyl)-2-oxoacetate (1), together with ten known compounds (2–11), were isolated from the marine algicolous fungus, Aspergillus sp. SCSIO 41304. Their planar structures and absolute configurations were elucidated by detailed NMR, MS spectroscopic analysis and comparing with literature data. Compound 1 was isolated as a new fungal secondary metabolite, possessing a methyl glyoxylate moiety R-CO-CO-OCH3, which is rare in natural sources. All the isolated compounds (1–11) were tested for their antibacterial and enzyme inhibitory activities against acetylcholinesterase (AChE) and pancreatic lipase (PL). Among these compounds, aspulvinone H (4) showed moderate inhibition against AChE and PL with IC50 values of 25.95 and 47.06 μM, respectively. Further molecular docking simulation exhibited that compound 4 could well bind to the catalytic pockets of the AChE and PL. [ABSTRACT FROM AUTHOR]

A new indole diketopiperazine alkaloid, named penilline D (1), together with five known indole alkaloid analogues (2–5, 11), two meroterpenoids (6 and 12), and four butenolide derivatives (7–10), were isolated from the Antarctic fungus Penicillium sp. SCSIO 05705. Extensive spectroscopic analysis and electronic circular dichroism (ECD) calculation were used to elucidate the structure of penilline D (1), including its absolute configuration. All isolated compounds (1–12) were evaluated for their cytotoxic, antibacterial and enzyme inhibitory activities against acetylcholinesterase (AChE) and pancreatic lipase (PL). Among them, compound 5 exhibited moderate in vitro cytotoxic activity against the 143B cell line with IC50 value of 12.64 ± 0.78 μM. Compound 6 showed strong inhibitory activity against AChE with IC50 value of 0.36 nM (IC50 18.7 nM for Tacrine), while compounds 6 and 11 showed weak PL enzyme inhibitory activity. Furthermore, an in silico molecular docking study was also performed between 6 and AChE. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We identify and investigate a possible correlation between the |$\rm {[C\,II]} \,158{-}{\mu }m$| luminosity and linewidth in the |$\rm {[C\,II]}$| -detected galaxies. Observationally, the strength of the |$\rm {[C\,II]}\, 158{-}{\mu }m$| emission line is usually stronger than that of the carbon monoxide (CO) emission line and this |$\rm {[C\,II]}$| line has been used as another tracer of the galactic characteristics. Moreover, many |$\rm {[C\,II]}$| -detected galaxies are identified in z  > 4. Motivated by previous studies of the CO luminosity–full width at half-maximum correlation relation (LFR) and the available new |$\rm {[C\,II]}$| measurements, we compile samples of the |$\rm {[C\,II]}$| -detected galaxies in the literature and perform the linear regression analysis. The |$\rm {[C\,II]}$| LFR is confirmed at a robust level. We also demonstrate the possible application of the |$\rm {[C\,II]}$| LFR by utilizing it on the distance measurement of the high- z galaxy. As a result, we extend the cosmic spatial scale beyond the redshift z of 7. With the outcome of the distance measurement, we constrain the cosmology parameters in the Chevallier–Polarski–Linder model, which considers the evolution of dark energy. Consequently, the uncertainties of the w 0 and wa are reduced significantly when the measured distance data of the |$\rm {[C\,II]}$| -detected galaxies are included in the cosmological parameter constraint, exemplifying the potential of using the |$\rm {[C\,II]}$| -detected galaxies as a tracer to constrain the cosmological parameters. [ABSTRACT FROM AUTHOR]

Tannic acid is a kind of plant polyphenol compound, which widely exists in roots, stems and leaves of plants. Hydrolyzed tannic acid has many biological functions, such as anti-diarrhea, anti-oxidation, anti-inflammatory, bacteriostasis, etc. It plays an important role in maintaining animal intestinal health and improving animal growth performance. The paper summarizes the physicochemical properties, biological functions and application of hydrolyzed tannic acid in animal husbandry, to provide reference for its rational application in animal husbandry. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (hBN) has recently been demonstrated to contain optically polarized and detected electron spins that can be utilized for implementing qubits and quantum sensors in nanolayered-devices. Understanding the coherent dynamics of microwave driven spins in hBN is of crucial importance for advancing these emerging new technologies. Here, we demonstrate and study the Rabi oscillation and related phenomena of a negatively charged boron vacancy (V B − ) spin ensemble in hBN. We report on different dynamics of the V B − spins at weak and strong magnetic fields. In the former case the defect behaves like a single electron spin system, while in the latter case it behaves like a multi-spin system exhibiting multiple-frequency dynamical oscillation as beat in the Ramsey fringes. We also carry out theoretical simulations for the spin dynamics of V B − and reveal that the nuclear spins can be driven via the strong electron nuclear coupling existing in V B − center, which can be modulated by the magnetic field and microwave field. Understanding the coherent dynamics of electron and nucleus spins in hBN is crucial for their applications as qubits and quantum sensors. Here the authors report room-temperature coherent manipulation of the negatively charged boron vacancy spins in hBN and study their dynamics under weak and strong magnetic fields. [ABSTRACT FROM AUTHOR]

A new method (electrode induction gas atomization, EIGA) of producing high-speed steel powder was preliminarily studied by a combination of numerical simulation and experiment. Based on COMSOL Multiphysics® software, the effect of various parameters including coil angle, output frequency and power of the electrical source on flux density, induced current, temperature field and phase field was simulated. Meanwhile, the experiment was carried out on the EIGA device to produce high-speed steel powder. The results of FEM simulation indicate that when the coil angle is 30°, there is the highest thermal efficiency on the electrode cone, and the induced current and temperature will increase as the output frequency and power of the electrical source increase. In addition, the powder experimentally obtained by the EIGA method exhibits good particle sphericity regardless of the size, with a median diameter (D50) of 71.4 μm and a low oxygen content of 81 μg/g. The phase composition of the powder is mainly composed of γ-Fe and α-Fe structures and MC-type carbides. Due to the faster cooling rate, a solidification microstructure consists of fine cellular crystals and dendrites, and no coarse eutectic carbide network is observed, also confirmed by EDX elemental mapping. [ABSTRACT FROM AUTHOR]

One new citrinin monomer derivative (1), and two new natural products α-pyrone analogues (2a and 2b), were isolated from the sponge derived fungus Penicillium sp. SCSIO 41302. Their structures were determined by extensive spectroscopic analysis, chiral-phase HPLC analysis, modified Mosher's method, ECD calculations, and X-ray single-crystal diffraction. Bioactivity screening showed that compounds 2b and 8 exhibited obvious inhibitory activities against pancreatic lipase and acetyl cholinesterase with IC50 values of 48.5 and 4.8 μM, respectively, which indicated that different chiral center between enantiomers (2a and 2b) might result in different biological activities (IC50 value against PL for 2a >100 μg/ml). [ABSTRACT FROM AUTHOR]

In this letter, the convolutional implementation of the complex frequency shifted perfectly matched layer (CFS-PML) absorbing boundary condition (ABC) is proposed for the finite-difference time-domain (FDTD) method of solving wave equation. The FDTD solution time-marching formulations of the developed wave-equation convolutional CFS-PML (CPML) ABC are derived. Several numerical experiments are used to verify the capacity of the proposed algorithm. Solution results confirm that the proposed CPML ABC can obtain excellent absorption for both traveling waves and evanescent waves. [ABSTRACT FROM AUTHOR]

Background: The principal objective of this project was to investigate the Epidermal Growth Factor Receptor (EGFR) gene mutation characteristics of lung cancer patients, which can provide a molecular basis for explaining the clinicopathological features, epidemiology and use of targeted therapy in lung cancer patients in the coal-producing areas of East Yunnan. Methodology: We collected 864 pathologically confirmed lung cancer patients' specimens in First People's Hospital of Qujing City of Yunnan Province from September 2016 to September 2021. We thereafter employed Next Generation Sequencing (NGS) technology to detect all exons present in the EGFR gene. Results: The overall mutation frequency of the EGFR gene was 47.22%. The frequency of EGFR gene mutations in the tissue, plasma, and cytology samples were found to be 53.40%, 23.33%, and 62.50%, respectively. Univariate analysis indicated that the coal-producing areas and Fuyuan county origin were significantly associated with relatively low EGFR gene mutation frequency. Female, non-smoking history, adenocarcinoma, non-brain metastasis, and tissue specimens were found to be related to high EGFR gene mutation frequency. Multivariate logistic regression analysis suggested the lung cancer patients in the central area of Qujing City, stage Ia, non-coal-producing areas, non-Fuyuan origin, and non-Xuanwei origin were more likely to develop EGFR gene mutations. The most common mutations were L858R point mutation (33.09%) and exon 19 deletion (19-del) (21.32%). Interestingly, the mutation frequency of G719X (p = 0.001) and G719X + S768I (p = 0.000) in the coal-producing areas were noted to be more significant than those in non-coal-producing regions. Conclusion: This findings of this study might be important in establishing the correlation between routine using NGS for EGFR gene mutation diagnosis and clinical practice in the lung cancer patients. [ABSTRACT FROM AUTHOR]

Spin defects in silicon carbide (SiC) with mature wafer-scale fabrication and micro/nano-processing technologies have recently drawn considerable attention. Although room-temperature single-spin manipulation of colour centres in SiC has been demonstrated, the typically detected contrast is less than 2 |$\%$|⁠ , and the photon count rate is also low. Here, we present the coherent manipulation of single divacancy spins in 4H-SiC with a high readout contrast (⁠|$-30\%$|⁠) and a high photon count rate (150 kilo counts per second) under ambient conditions, which are competitive with the nitrogen-vacancy centres in diamond. Coupling between a single defect spin and a nearby nuclear spin is also observed. We further provide a theoretical explanation for the high readout contrast by analysing the defect levels and decay paths. Since the high readout contrast is of utmost importance in many applications of quantum technologies, this work might open a new territory for SiC-based quantum devices with many advanced properties of the host material. [ABSTRACT FROM AUTHOR]

The catalytic hydrogenolysis of 2,4,6,8,10,12‐hexabenzyl‐2,4,6,8,10,12‐hexaazaisowurtzitane (HBIW) over Pd‐based catalysts in the ternary solvents of acetic anhydride, bromobenzene (PhBr) and N, N'‐dimethylformamide (DMF) was the key step for producing 2,4,6,8,10,12‐hexanitro‐2,4,6,8,10,12‐hexaazaisowurtzitane (HNIW or CL‐20). However, the role of the bromobenzene is still allusive. Herein, Pd/graphite carbon nitride nanosheets (g‐C3N4 NS) was used in the hydrogenolysis of HBIW under the atmospheric pressure, and exhibited a yield of 80 % as well as a faster debenzylation rate than Pd/C. By the virtue of the kinetic study, the effect of the bromide, solvent and proton on the debenzylation rate was investigated and discussed. The bromide worked as a co‐catalyst to promote the desorption of the product of the hydrogenolysis from the surface of the palladium nanoparticle. The observation benefits for elucidating the reaction mechanism and may inspire the design of the novel catalysts for the hydrogenolysis of HBIW. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of autophagy expression levels of different weight‐bearing states and different stages of osteoarthritis in animal models, as well as the corresponding mechanisms. Methods: We used the male Sprague–Dawley (SD) rats (12‐week‐old, SPF) to establish the OA animal models by modified Hulth method, and grouped animal models according to the length of time after surgery and different weight‐bearing areas. RT‐qPCR was carried out for detection of autophagy‐related genes such as Atg7, Atg12, P62, etc. Western blot analysis was used to detect the expression levels of corresponding autophagy‐related proteins such as LC3B, P62, etc. T test was performed for statistical analysis to compare different groups, while the differences were deemed statistically significant with P < 0.05. Transmission electron microscopy was used to observe the autophagosome to demonstrate the level of autophagy expression and the status of the chondrocytes. Results: The results of the RT‐qPCR testing showed that when the weight‐bearing cartilage of the 4‐week group (relatively mild) was compared with that of the 10‐week group (relatively severe), there were statistically significant differences in all the genes tested, in detail: Atg3 (P < 0.01), Atg7 (P < 0.01), Atg12 (P < 0.01), P62 (P < 0.0001). The expression of autophagy‐related mRNA in the 4‐week group is increased compared with that of the 10‐week group. As for the expression of proteins, Western blotting showed that in the comparison between the 4‐ and the 10‐week groups, statistically significant results include Atg12 (P < 0.01) in the non‐weight‐bearing area, with decreased autophagy in the 10‐week group compared with that of the 4‐week group, while expression of LC3B (P < 0.05) protein was significantly higher in the 4‐week group than in the control in the non‐weight‐bearing area. The expression of LC3B (P < 0.0001) and P62 (P < 0.05) in the 10‐week group were higher than that of the control. Transmission electron microscope showed that autophagy in the weight‐bearing area is stronger than that in the non‐weight‐bearing area, and autophagy in the 4‐week group is stronger than in the 10‐week group for the weight‐bearing area. Conclusions: The expression of autophagy varies during different stages of osteoarthritis, in which the autophagy is stronger in the early stage of osteoarthritis, and gradually decreases with the progression of the disease. Autophagy in different weight‐bearing areas may also be different. [ABSTRACT FROM AUTHOR]

A new diketopiperazine, cyclo-(d-8-acetoxyl-Pro-l-Leu) (1), together with eight known compounds (2–9) including three enterotoxins (2–4), four diketopiperazines (5–8) and maltol (9), were isolated from the mangrove derived-soil Streptomyces sp. SCSIO 41400. The planar structures of all compounds were determined from analysis of NMR spectra, MS, optical rotation and comparing with literature data. The absolute configuration of compound 1 was assigned by electronic circular dichroism (ECD). The isolated compounds (1–9) were tested for their acetyl cholinesterase (AChE) and pancreatic lipase (PL) enzyme inhibitory activities. Among them, the new diketopiperazine (1) displayed preferable PL enzyme inhibitory activity with IC50 value of 27.3 μg/mL, while compounds 2, 5 and 6 showed weak PL enzyme inhibitory activity. Further molecular docking simulation exhibited that compound 1 could be well bind with the catalytic pocket of the PL. Besides, compound 9 showed moderate antibacterial activity against Methicillin-resistant Staphylococcus aureus with MIC value of 12.5 μg/mL, which was comparable to that of the positive control ampicillin with MIC value of 3.125 μg/mL. [ABSTRACT FROM AUTHOR]

The causes of water eutrophication and various common remediation methods, such as physical remediation' chemical remediation; bioremediation and compound remediation; were reviewed. The effects of different remediation methods on the treatment of N; P and other pollution factors in eutrophication of water bodies were analyzed; and the advantages and disadvantages of various remediation techniques were summarized. Based on the research progress of water eutrophication remediation technology; it is pointed out that bioremediation and composite remediation should be the main remediation technology, and physical and chemical remediation should be the supplementary remediation technology,and it is suggested that the combination of remediation technology and space technology can more effectively remediation and monitoring of water eutrophication pollution. In addition; remediation technologies such as algae-microbial fuel cells, which only control phosphorus but not nitrogen; have low cost and ideal effect, and are worthy of further study and application. [ABSTRACT FROM AUTHOR]

Experimental and clinical therapies in the field of Alzheimer's disease (AD) have focused on elimination of extracellular amyloid beta aggregates or prevention of cytoplasmic neuronal fibrillary tangles formation, yet these approaches have been generally ineffective. Interruption of nuclear lamina integrity, or laminopathy, is a newly identified concept in AD pathophysiology. Unraveling the molecular players in the induction of nuclear lamina damage may lead to identification of new therapies. Here, using 3xTg and APP/PS1 mouse models of AD, and in vitro model of amyloid beta42 (Aβ42) toxicity in primary neuronal cultures and SH‐SY5Y neuroblastoma cells, we have uncovered a key role for cathepsin L in the induction of nuclear lamina damage. The applicability of our findings to AD pathophysiology was validated in brain autopsy samples from patients. We report that upregulation of cathepsin L is an important process in the induction of nuclear lamina damage, shown by lamin B1 cleavage, and is associated with epigenetic modifications in AD pathophysiology. More importantly, pharmacological targeting and genetic knock out of cathepsin L mitigated Aβ42 induced lamin B1 degradation and downstream structural and molecular changes. Affirming these findings, overexpression of cathepsin L alone was sufficient to induce lamin B1 cleavage. The proteolytic activity of cathepsin L on lamin B1 was confirmed using mass spectrometry. Our research identifies cathepsin L as a newly identified lamin B1 protease and mediator of laminopathy observed in AD. These results uncover a new aspect in the pathophysiology of AD that can be pharmacologically prevented, raising hope for potential therapeutic interventions. [ABSTRACT FROM AUTHOR]

Twelve indole alkaloids, including α-cyclopiazonic acid (CPA) (1), nine 2-oxo indole CPA derivatives (2–10), and two open-ring indole CPA derivatives (11 and 12), were isolated from the fermentation broth of a deep-sea derived fungus Aspergillus sp. SCSIO 41024. Their structures and absolute configurations were elucidated mainly by using extensive NMR spectroscopic, mass spectrometric and single crystal X-ray diffraction analysis. To the best of our knowledge, the crystallographic data of 3 and 7 were firstly reported, and the absolute configuration of 3 was confirmed for the first time by the single crystal X-ray diffraction analysis. Most isolated compounds were tested for their antimicrobial, antitumor and radical scavenging activities. In addition, compounds 1, 2 and 11 showed moderate antioxidative activity against DPPH with IC50 values of 190.1, 31.9, 228.4 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

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To investigate whether miR-124-3p influences cell apoptosis, inflammatory response, and oxidative stress in rats with acute myocardial infarction (AMI) by mediating the SIRT1/FGF21/CREB/PGC1α pathway. A dual-luciferase reporter gene assay was performed to verify the relationship between miR-124-3p and SIRT1. AMI rats were established via coronary artery ligation after injection with agomiR-124-3p, antagomiR-124-3p, and/or SIRT1 siRNA, and triphenyltetrazolium chloride (TTC), HE, and TUNEL stainings were performed. Bio-Plex rat cytokine assays were performed to determine proinflammatory factor levels. qRT-PCR and Western blotting were used to examine the mRNA and protein expression, respectively. The activity levels of antioxidant enzymes in myocardial tissues were also measured. miR-124-3p was confirmed to target SIRT1 in the H9C2 cells. AMI rats exhibited increased miR-124-3p expression and decreased SIRT1 expression in myocardial tissues. HE staining showed a disorganized cell arrangement and inflammatory cell infiltration in the myocardial tissues of the AMI rats, which was more severe in the rats injected with SIRT1 and agomiR-124-3p but was ameliorated in those treated with antagomiR-124-3p. Moreover, the AMI rats in the antagomiR-124-3p group presented with a reduction in infarct area with an increase in antioxidant enzyme activity, Bcl-2 expression, and activation of the FGF21/CREB/PGC1α pathway, as well as a decrease in cell apoptosis rate, Bax and Caspase-3 expression, and levels of proinflammatory factors, effects that were reversed by si-SIRT1. Inhibiting miR-124-3p expression may activate the FGF21/CREB/PGC1α pathway to reduce cell apoptosis, alleviate the inflammatory response, and attenuate oxidative stress in AMI rats by targeting SIRT1. [ABSTRACT FROM AUTHOR]

Winter construction in seasonally frozen soil areas is inevitable. The variation of ambient temperature causes the freeze-thaw of the filling soils and its impact is significant, and whether the countermeasures can be effectively established and adopted is particularly important for the management and control of the construction quality of the project. This paper conducts systematic research based on the winter construction process of the dam core wall of the Lianghekou Hydropower Station, which is the third highest earth-core rockfill dam in the world under construction. The results show that for the construction site in the seasonally frozen soil area, there is a development process of the short-term frozen soils for the filling soils under the environment with low temperature in winter. The soil underwent a high-frequency freeze-thaw process wherein it was frozen at night and completely thawed during the day. During the freezing process, a large number of thin-layered segregated ice developed inside the soil to form a thin-layered or integral cryostructure, which will have an adverse effect on the engineering properties and the quality of the filling soils. And, the field tests demonstrate that the filling compaction degree of the frozen soils is difficult to meet the designed requirements. In order to effectively cope with the adverse effect of the freeze-thaw on the construction quality during the construction process, based on the analysis of the freeze-thaw characteristics of soils and its influence, and the energy exchange process of soils on-site, the principles and methods for establishing the freeze prevention system during the winter construction process are established, and a comprehensive monitoring system suitable for on-site is established in this paper. This research will provide an important reference for the scientific management and efficiency improvement of the winter construction process of the dams in cold regions. [ABSTRACT FROM AUTHOR]

In this paper, a plasmonic photo-assisted electrochemical sensor, Au anchored on two-dimensional (2D) graphitic carbon nitride (g-C3N4)/reduced graphene oxide (rGO) nanosheets (Au/g-C3N4/rGO), was facile fabricated. The morphology and structure of the composite are characterized by transmission electron microscope, X-ray photoelectron spectroscopy, X-ray diffraction and ultraviolet–visible spectrophotometer (UV–Vis). Based on the semiconductor of g-C3N4 and optical properties of surface plasmon resonance for Au, the as-prepared Au/g-C3N4/rGO showed high sensitivity for the detection of trace lead ion [Pb(II)] by differential pulse anodic stripping voltammetry in the presence of visible light illumination. Under optimized conditions, the limit of detection (signal-to-noise ratio (S/N) = 3) Pb(II) detection can be low to 0.1 nmol·L−1. In addition, the interference research and real soil sample detection were measured to confirm the possibility of practical applications. [ABSTRACT FROM AUTHOR]

Immobilization of soil cadmium (Cd) has been the strategy mostly used in remediation of Cd-contaminated arable soil. However, Cd might be remobilized after the immobilization process through the acid-soluble and complexation effects. Development of agronomic management technologies to prevent soil Cd remobilization after the immobilization process was an important pathway to control the food safety of agricultural products in soils with the immobilized Cd. In this study, the ammonia (NH4+-N) and nitrate (NO3−-N) forms with concentrations of 60, 90, and 150 mg-N kg−1 soil were performed for evaluating their effects on Cd remobilization with planted or unplanted treatments and Cd accumulation in tissues of edible amaranth (Liuye). With an initial soil palygorskite-bound fraction Cd concentration of 0.6 mg kg−1, bioavailable Cd in rhizosphere soils and Cd in crop shoots respectively increased from 11.4 to 20.6 μg kg−1 (dry soil weight) and 6.92 to 14.92 mg kg−1 (dry plant weight) in planted NH4+-N treatments, while significantly lower concentrations of bioavailable Cd in rhizosphere soils and Cd in crop tissues were observed with planted NO3−-N treatments. Compared with that of planted NO3−-N treatments, decreasing pH value (i.e., 7.64 to 7.18) induced by root proton efflux during the absorption of NH4+-N, enhancive organic/amino acid (oxalic acid, lactic acid, l-proline, and so on) secretion from roots, and increasing abundance of bacteria distributed in phyla Proteobacteria, Cyanobacteria, and Bacteroidetes with Cd mobilization ability in rhizosphere soils were the main reasons found in this study for the higher Cd remobilization in soils and Cd accumulation in crop under NH4+-N treatments. Moreover, the direct effect of NH4+-N on remobilization of immobilized Cd by upregulating the expression abundances of genes associated with pyruvate metabolism and amino acids metabolism was more significant than that of NO3−-N. In summary, the use of NO3−-N as preferred N fertilizer was more efficient to ensure the food safety of agricultural products than that of NH4+-N in Cd-contaminated arable soil after immobilization process. [ABSTRACT FROM AUTHOR]

In this communication, the recursive convolutional complex frequency shifted perfectly matched layer (CFS-PML) absorbing boundary condition (ABC) is developed for the wave-equation-based meshless method. The numerical results show that the proposed CFS-PML can achieve an excellent absorption performance with the reflections less than −52.5 dB when the six layers of the PML are applied, and less than −57.3 dB when ten layers of the PML are applied (including operations with evanescent waves). The impacts of the CFS-PML parameters, shape parameter, and different node distribution types are also investigated. Such performances allow the use of the wave-equation-based meshless method for solving open problems. [ABSTRACT FROM AUTHOR]

Optically addressable solid-state color center spin qubits have become important platforms for quantum information processing, quantum networks and quantum sensing. The readout of color center spin states with optically detected magnetic resonance (ODMR) technology is traditionally based on Stokes excitation, where the energy of the exciting laser is higher than that of the emission photons. Here, we investigate an unconventional approach using anti-Stokes excitation to detect the ODMR signal of silicon vacancy defect spin in silicon carbide, where the exciting laser has lower energy than the emitted photons. Laser power, microwave power and temperature dependence of the anti-Stokes excited ODMR are systematically studied, in which the behavior of ODMR contrast and linewidth is shown to be similar to that of Stokes excitation. However, the ODMR contrast is several times that of the Stokes excitation. Coherent control of silicon vacancy spin under anti-Stokes excitation is then realized at room temperature. The spin coherence properties are the same as those of Stokes excitation, but with a signal contrast that is around three times greater. To illustrate the enhanced spin readout contrast under anti-Stokes excitation, we also provide a theoretical model. The experiments demonstrate that the current anti-Stokes excitation ODMR approach has promising applications in quantum information processing and quantum sensing. Optically detected magnetic resonance of defect spins typically relies on Stokes excitation, in which the excitation energy is larger than that of the emitted photon. Here, the authors use the opposite regime of anti-Stokes excitation to detect Si vacancy spins in SiC, with a threefold improvement in signal contrast. [ABSTRACT FROM AUTHOR]

Background and aims: Three to 10 minutes of smoking cessation advice by physicians is effective to increase quit rates, but is not routinely practised. We examined the effectiveness of physicians' very brief (approximately 30 sec) smoking cessation intervention on quit rates among Chinese outpatient smokers. Design A pragmatic, open‐label, individually randomized controlled trial. Setting Seventy‐two medical outpatient departments of hospitals and/or community health centers in Guangdong, China. Participants: Chinese adults who were daily cigarette smokers (n = 13 671, 99% males) were invited by their physician to participate during outpatient consultation. Smokers who were receiving smoking cessation treatment or were judged to need specialist treatment for cessation were excluded. Interventions: The intervention group (n = 7015) received a 30‐sec intervention including physician's very brief advice, a leaflet with graphic warnings and a card with contact information of available cessation services. The control group (n = 6656) received a very brief intervention on consuming vegetables and fruit. A total of 3466 participants in the intervention group were further randomized to receive a brief booster advice from trained study personnel via telephone 1 month following their doctor visit. Measurements The primary outcome was self‐reported 7‐day point prevalence abstinence (PPA) in the intervention and control groups at the 12‐month follow‐up. Secondary outcomes included self‐reported 30‐day abstinence and biochemically validated abstinence at 12‐month follow‐up. Findings By intention‐to‐treat, the intervention (versus control) group had greater self‐reported 7‐day abstinence [9.1 versus 7.8%, odds ratio (OR) = 1.14, 95% confidence interval (CI) = 1.03–1.26, P = 0.008] and 30‐day abstinence (8.0 versus 6.9%, OR = 1.14, 95% CI = 1.03–1.27, P = 0.01) at 12‐month follow‐up. The effect size increased when only participants who received the intervention from compliant physicians were included (7‐day PPA, OR = 1.42, 95% CI = 1.11–1.74). The group difference in biochemically validated abstinence was small (0.8 versus 0.8%, OR = 1.00, 95% CI = 0.71–1.42, P = 0.99). Conclusion: A 30‐sec smoking cessation intervention increased self‐reported abstinence among mainly male smokers in China at 12‐month follow‐up (risk difference = 1.3%), and should be feasible to provide in most settings and delivered by all health‐care professionals. [ABSTRACT FROM AUTHOR]

Compact steep-spectrum sources (CSSs) likely represent a population of young radio-loud active galactic nuclei (AGNs) and have been identified as γ-ray-emitting sources. We present a comprehensive analysis of their γ-ray emission observed with Fermi/LAT and establish their broadband spectral energy distributions (SEDs). We derive their jet properties using SED fits with a two-zone leptonic model for radiation from the compact core and the large-scale extended region, and explore the possible signature of a unification picture of jet radiation among subclasses of AGNs. We show that the observed γ-rays of CSSs with significant variability are contributed by the radiation of their compact cores via the inverse-Compton process of the torus photons. The derived power-law distribution index of the radiating electrons is p1 ∼ 1.5–1.8, magnetic field strength is B ∼ 0.15–0.6 G, and Doppler-boosting factor is δ ∼ 2.8–8.9. Assuming that the jet is composed of e± pairs, the compact cores of CSSs are magnetized and have a high radiation efficiency, similar to that of flat-spectrum radio quasars. The γ-ray-emitting CSSs on average have higher Eddington ratio and black hole mass than those non-GeV-detected CSSs, and they follow the correlation between the jet power in units of Eddington luminosity () and Eddington ratio (REdd) with other subclasses of AGNs, , indicating that REdd would be a key physical driver for the unification scheme of AGN jet radiation. [ABSTRACT FROM AUTHOR]

Aims: Uncovering the importance of soil and plant characteristics in driving the legacy effects of nitrogen (N) deposition on plant community nutrient stoichiometry would improve our understanding of plant-soil interaction during restoration of historically N-enriched ecosystems. Methods: Based on a field experiment with the cessation of six-year N addition in a temperate steppe of northern China, we measured concentrations and stoichiometry of N and phosphorus (P) in soils and different plant functional groups, under both mown and unmown conditions. Results: Historical N addition did not affect soil total and available N and P concentrations and stoichiometry, but significantly altered plant community composition. Plant nutrient concentrations and N:P ratios significantly differed among four plant functional groups. The concentrations and stoichiometric ratios of N and P between soils and plants were generally not correlated. The positive legacy effects of N addition on community N:P stoichiometry were caused by the biomass enhancement of tall bunchgrass, the functional group with the highest N:P ratios. Conclusions: Changes in plant community composition instead of soil nutrient status were the main driver for the positive legacy effects of N enrichment on plant community stoichiometry. Given that the recovery of community composition after the cessation of N deposition is generally slow, our findings indicate that the legacy effects of N deposition on soil nutrient cycling would persist in long-term due to the importance of plant-mediated pathway. [ABSTRACT FROM AUTHOR]

A field survey was performed to investigate the metals contamination in the vicinity of tungsten mining areas. Ten sampling sites alongside perennial wind direction were selected for soil collection and heavy metal contents determination, include Cr, Cu, Zn, Pb, As, Cd, and W. Horizontal and vertical distribution characteristics of metals were performed. Geo-accumulation and potential ecological risk of soil samples were discussed for a description of risk assessment. The results showed that the mean concentrations of all metals in soil samples exceeded the background value of Jiangxi background. The heavy metal contents in vertical profiles revealed the surface accumulation of Cd, W, and Pb, while, As increased as soil depth increased. The geo-accumulation index shown the highest pollution level of W and followed by Cd. Single ecological risk factor ( E r i ) figured out that the contamination degree followed the sequence of Cd>As>W>Zn>Pb>Cr>Cu. Furthermore, the potential ecological risk index ( R I) was calculated for risk level assessment, and Cd takes account the most contribution in surface soil, followed by W and As. [ABSTRACT FROM AUTHOR]