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A series of novel silane-based hyper-cross-linked porous polymers was prepared through the Friedel-Crafts alkylation reaction of dimethyldiphenylsilane as the monomer and formaldehyde dimethyl acetal as the external cross-linker. The structures of the polymers were confirmed by FTIR and solid-state cross-polarization magic-angle spinning 13C NMR. We investigated the porous polymers with different ratios of dimethyldiphenylsilane to formaldehyde dimethyl acetal. Porous properties were determined by nitrogen, carbon dioxide and hydrogen adsorptions. The results revealed that the porous materials possessed surface areas from 742 to 1205 m2 g−1 with the increasing amount of formaldehyde dimethyl acetal. Moreover, this material exhibited high thermal stabilities, good CO2 capture, and H2 storage capacities. The material was also used as adsorbent for organic dyes in aqueous solution and showed an excellent adsorption capacity of 952 mg g−1 for Congo red dye. These results suggest that the silane-based hyper-cross-linked porous polymers are promising materials for CO2 capture, H2 storage, and water treatment. [ABSTRACT FROM AUTHOR]

In this work, a novel CoO/CoFe 2 O 4 bi-component nanorod coated with S-doped carbon nanospheres shell (CO/CFO@SC Nr) composites have been synthesized through one in-situ polymerization and subsequent annealing treatment. The S-doped carbon shell, special structure and synergistic effect between CoO and CoFe 2 O 4 significantly enhance the electrochemical performance of the CoO/CoFe 2 O 4 anode material. CO/CFO@SC Nr composites present an impressive capacity of 511.3 mAh g −1 after 700 cycles when tested at a high current density of 2000 mA g −1 . In addition, this is the first time that polythiophene is used as sulfur and carbon source to synthesis transition metal oxide (TMO) @S-doped carbon core-shell composites. This work illuminates a new preparation way for fabrication other TMO@S-doped carbon core-shell materials for lithium-ion batteries and other energy storage devices. [ABSTRACT FROM AUTHOR]

The sedimentary rhythm is well developed in the environment which is controlled by strong seasonal climate changing condition. This rhythm is important for sediment core dating purpose. In this study, we examine muddy sediments on the inner continental shelf of the East China Sea that are influenced under seasonal change of the East Asian monsoon. We use Ensemble Empirical Mode Decomposition (EEMD) method to process sediment grain size and X-radiograph negatives grayscale value data in three sediment cores from this area and use the results to analyze the patterns of sedimentary variability and the causes of cyclic variability of the sedimentary process. The variability in the grain size and grayscale values of the core sediments has three components: the high-frequency variability, low-frequency variability and a secular trend. Among these components, the high-frequency component reflects variability on annual time scale can be well recognized, we suggest that the annual variability is derived from seasonal variation in the sediment flux from the Yangtze River to the sea, as well as the East Asian monsoon's impact on the sedimentary dynamics of the East China Sea's inner continental shelf. However, the other variability is hard to identify which cycles there are. This variability may reflect decadal winter monsoon oscillation and human activity of dam construction in the Yangtze River. Each annual variability presents a varve in the sediment sequence, which can be used to determine the sediment deposition rate and accurately date the core sediment. We found that the average deposition rates of the three cores from north to south on the inner shelf were 3.1 cm/yr, 1.0 cm/yr, 0.9 cm/yr, indicating that the Yangtze-derived sediment decreased with the increasing distance from the Yangtze estuary to the shelf. The deposition rate of each core varies over time, and the maximum deposition rate can be 3–5 times greater than the minimum rate. The sediment ages obtained from varve chronology and radiometric dating are fairly consistent on a centennial scale, differing only by 2–5 years. Thus, varve counting is a useful supplementary approach to radiometric age dating for constructing chronologies for core sediment in shelf seas influenced by monsoons. [ABSTRACT FROM AUTHOR]

• A multi-timescale voltage control model is formulated to control different timescale regulators. • The control variables of these regulators are assigned to multiple agents. Through centralized training and decentralized execution, these agents can obtain optimal coordinated control strategy. • A MADRL-based method is proposed to obtain the control strategy, which is based on the MADDPG algorithm and spplies Gumbel-Softmax distribution to solve discrete actions. Nowadays a large number of distributed generators and controllable elements connecting to the distribution network have resulted in higher requirements for voltage control. Existing voltage control methods require a specific physical model and are time-consuming with the complexity increasing. To overcome these challenges, this paper proposes a multi-timescale voltage control scheme using multi-agent deep reinforcement learning (MADRL). Firstly, considering the control requirements of different timescale regulators, a multi-timescale voltage control model is formulated. Then the control variables are assigned to multiple agents, and a MADRL-based voltage control scheme is proposed, which is based on the multi-agent deep deterministic policy gradient (MADDPG) algorithm and applies Gumbel-Softmax distribution to solve discrete actions. Through centralized learning and decentralized execution, this scheme can obtain the optimal coordinated control strategy of multiple regulators adaptively and achieve the effect of distributed control. Finally, case studies are conducted on the modified IEEE-123 bus system, and the performance of the proposed method is compared with the conventional model-based optimal voltage control scheme and other DRL-based methods. The results show that the MADRL-based method possesses better performance than other methods. [ABSTRACT FROM AUTHOR]

In this work, sugarapple-like N-doped TiO 2 @N-doped carbon (NTiO 2 @NC) core-shell spheres have been synthesized with a facile and effective preparation process using polypyrrole (PPy) as carbon and nitrogen sources. Conductive N-doped carbon with slit pores uniformly coated on the TiO 2 spheres surface. Benefiting from the N-doping and carbon shell, NTiO 2 @NC demonstrates superior long-term cycling stability and high-rate performance as anode materials for lithium ion batteries. Even tested at a current density of 5000 mA g −1 , the NTiO 2 @NC composites can deliver a reversible capacity of 232.7 mAh g −1 after 2000 cycles. This new strategy may shed light on preparing metal oxides@NC core-shell composites for Li-ion batteries and other energy storage applications. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable zinc ion batteries (ARZIBs) are environmental-friendly and recyclable batteries, but they still have some problems restricting their practical application, such as poor cycle life-span and high possibility of internal short circuits due to the growth of dendrite. Herein, the electrode by electrodeposited manganese dioxide on the Zn metal has been designed, which can guide uniform deposition of zinc on the electrode, and then greatly extend the service life and improve the long cycling stability of ARZIBs. The modified electrode achieved favorable stability with a 10-fold enhancement in running lifetime (over 3950 h) compared to the pristine Zn electrode at the current density of 0.1 mA cm−2 with 0.1 mAh cm−2, and a 5-fold longer running life than that of bare Zn at 1 mA cm−2 with 1 mAh cm−2. As a result, the electrodeposition technique for Zn metal anode modification is expected to develop inherently safe energy storage systems. [Display omitted] • Manganese dioxide cathode material is used for anodic surface modification. • Ultrathin manganese dioxide layer was prepared by electrochemical deposition. • The zinc anode modified by electrodeposited manganese dioxide has good electrochemical performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • N -doped biomass litchi-shell derived porous carbon was successfully synthesized. • The doping of N element provides more active sites and suppresses shuttle effect. • N -doped porous carbon as a matrix for iodine species can inhibit the self-discharge. • N -LPC/I 2 exhibits the excellent cycling stability for zinc iodine batteries. Zinc-iodine batteries (ZIBs) have attracted widespread attention because of their efficient capacity for ion transport and safety. However, the shuttle effect and physical properties of iodine species tremendously hinder their practical applications. Herein, we report a nitrogen-doped biomass litchi-shell derived porous carbon (marked as N -LPC) as the iodine host for ZIBs. The porous-rich structure of N -LPC is favorable for iodine loading and electron/ion transfers. Furthermore, the doping of heteroatomic nitrogen provides abundant anchoring sites to achieve strong interaction with iodine, thus the self-discharge can be suppressed effectively. Accordingly, the N -LPC/I 2 composite cathode exhibits a specific capacity of 127 mAh/g at 100 mA g−1, as well as excellent rate capability and cycle stability. This study provides a strategy for discovering the cost-effective carbonaceous iodine host material. [ABSTRACT FROM AUTHOR]

False detection of SARS-CoV-2 is detrimental to epidemic prevention and control. The scalar nature of the detected signal and the imperfect target recognition property of developed methods are the root causes of generating false signals. Here, we reported a collaborative system of CRISPR-Cas13a coupling with the stabilized graphene field-effect transistor, providing high-intensity vector signals for detecting SARS-CoV-2. In this collaborative system, SARS-CoV-2 RNA generates a "big subtraction" signal with a right-shifted feature, whereas any untargets cause the left-shifted characteristic signal. Thus, the false detection of SARS-CoV-2 is eliminated. High sensitivity with 0.15 copies/μL was obtained. In addition, the wide concerned instability of the graphene field-effect transistor for biosensing in solution environment was solved by the hydrophobic treatment to its substrate, which should be a milestone in advancing it's engineering application. This collaborative system characterized by the high-intensity vector signal and amazing stability significantly advances the accurate SARS-CoV-2 detection from the aspect of signal nature. [ABSTRACT FROM AUTHOR]

Poly(catechol-diethylenetriamine- p -phenylenediamine) (PCEA1) and Poly(catechol-diethylenetriamine-melamine) (PCEA2), two kinds of similar chelating adsorbents with analogous structures, were used for the comparative study on Cr(VI) removal from aqueous solution. Many methods were employed to characterize these adsorbents, including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and energy dispersive spectrometer (EDS). Batch experiments were carried out to investigate the adsorption performance of Cr(VI), such as pH value, adsorbent dosage, initial concentration, contact time and temperature. Furthermore, adsorption isotherm, intra-particle diffusion, kinetics and thermodynamics were studied completely and systematically. XPS technique confirmed that the reduction from toxic Cr(VI) to nontoxic Cr(III) existed in the adsorption process. After that, the removal of Cr(VI) in simulative wastewater caused by both adsorbents was nicely fitted with the Langmuir isotherm model and pseudo-second-order kinetic model. The maximum adsorption values of the PCEA1 and PCEA2 were 200 mg/g and 175.4 mg/g, respectively. The intra-particle diffusion study further demonstrated that adsorption processes all had two portions. The negative ΔG and positive ΔH indicated that the adsorption was spontaneous and endothermic. Tests on Cr(VI) removal indicated the potential applicability of the two adsorbents with a similar adsorption mechanism. [ABSTRACT FROM AUTHOR]

The "shuttle effect", tardy reaction kinetics and volume change of sulfur cathode limit the wide application of Li-S batteries (LSBs). In this work, a composite of flower-like CoOOH decorating hierarchical porous carbon (CoOOH-HPC) was successfully synthesized and utilized as a sulfur host for LSBs. SEM and TEM images exhibited that the flower-like CoOOH formed by nanosheets was uniformly dispersed on the hierarchical porous carbon which was constructed by carbon spheres and nanotubes. Nitrogen adsorption/desorption isotherm and pore size distribution revealed that the ultrahigh specific surface area and suitable uniform mesopores of the CoOOH-HPC. Benefitting from the perfect combination of CoOOH and HPC, the CoOOH-HPC/S electrode delivered satisfactory electrochemical performance. It remained a discharge capacity of 550.9 mA h g−1 after 270 cycles at 0.5 C, with a low capacity decay rate of 0.017 % per cycle and a stable coulombic efficiency (over 96 %). Besides, the CoOOH-HPC/S electrode with a high sulfur loading of 2.8 mg cm−2 can demonstrate a discharge capacity of 357.91 mA h g−1 after 500 cycles, with the capacity decay rate of 0.08 % per cycle. This work provided a new method for preparing a variety of metal-based compound decorative hierarchical porous carbon composites, which can be used in LSBs and other energy storage and conversion devices. [Display omitted] • A composite sulphur host of CoOOH decorating hierarchical porous carbon (CoOOH-HPC) was synthesized. • The CoOOH-HPC exhibits ultrahigh specific surface area and suitable pore volume. • The perfect structure facilitates wetting of electrolyte and diffusion of electron/Li+ in solid phase • The CoOOH can adsorb the lithium polysulfide through chemical adsorption and accelerate the conversion of the lithium polysulfide to Li 2 S [ABSTRACT FROM AUTHOR]

Li 3 V 2 (PO 4 ) 3 (LVP) nanoparticles were first prepared via a simple sol-gel route, then deposited on graphene oxide nanosheets, and finally a composite of LVP/reduced graphene oxide (LVP/G) was obtained after heat treatment. Scanning electron microscope and transmission electron microscope images demonstrate that LVP nanoparticles are homogenously enwrapped into graphene nanosheets or anchored onto the surface of graphene nanosheets. Compared with pure LVP, LVP/G nanocomposites exhibited better electrochemical performance (118.4 mAhg −1 at 1C, and 112.1 mAhg −1 at 2C after 100 cycles) and higher cycling stability (97% capacity retention after 100 cycles at 1C, and 89.5% after 500 cycles at 20C) as cathode materials for Li ion batteries. The enhanced performance can be attributed to the presence of graphene nanosheets among LVP nanoparticles. Electrochemical impedance spectroscopy indicates that graphene nanosheets significantly improve the electrical conductivity of LVP. The as-prepared LVP/G nanocomposites with superior cycling performance at high-rate have potential applications as cathode materials in Li ion batteries. [ABSTRACT FROM AUTHOR]

The practical application of aqueous zinc-iodine (Zn-I 2) battery is mainly hindered by the limited electrical conductivity, sluggish kinetics and severe shuttle effect. In this regard, herein, we designed a biomass-derived hierarchically porous carbon (marked as BC HP) as an iodine host material for high-performance Zn-I 2 battery. The hierarchically porous structure of BC HP is favourable for iodine confinements, electrolyte permeation as well as electron/ion transfers. As a result, the I-BC HP electrode exhibits superior electrochemical performance. A high discharge capacity of 100 mAh g−1 is still retained for over 150 cycles at a current density of 100 mA g−1. Our study provides an economical and effective scheme for the significant improvement of Zn-I 2 battery performance. [Display omitted] • Biomass-derived hierarchically porous carbon was prepared using gingko as precursor. • Porous carbon shows a high specific surface area of 1176 m2 g−1. • The outstanding cycling stability and high coulombic efficiency are obtained. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multi-functional electrocatalyst of CoOOH/hollow carbon sphere (PHCS) was synthesized. • DFT calculation confirms the catalytic performance of CoOOH for Li 2 S x conversion. • DFT calculation certificates the promotion of CoOOH on OER reaction kinetic. • The CoOOH-PHCS cathode delivers satisfactory lithium storage performance. • The CoOOH-PHCS demonstrates excellent OER and ORR activity in the alkaline electrolyte. Materials with excellent electrocatalytic properties play an important role in the field of electrochemistry. In this work, a multi-function electrocatalyst of cobalt oxyhydroxide decorating homogeneous porous hollow carbon sphere (CoOOH-PHCS) was designed and fabricated. The CoOOH-PHCS can not only be used as an electrocatalyst to inhibit the shuttle effect in Li-S batteries (LSBs), but also can effectively accelerate the reaction kinetics in oxygen reduction/evolution reactions (ORR/OER). Meanwhile, density functional theory (DFT) calculations were performed to investigate the electrocatalytic activity of the CoOOH-PHCS. Benefiting from the synergy effect of CoOOH and PHCS, the CoOOH-HPC/S electrode exhibits a low capacity decay of 0.04% per cycle in 450 cycles at 1C. Meanwhile, the CoOOH-PHCS demonstrates excellent OER and ORR activity in the alkaline electrolyte. This work explores and reveals the application potential of CoOOH in electrocatalytic field. [ABSTRACT FROM AUTHOR]

In this work, a composite of cobalt metal nanoparticles/three-dimensional carbon/reduced graphene oxide (Co-3DC-rGO) was synthesized using corn husk, ZIF-67, and graphene oxide as precursors. The Co-3DC-rGO was used to modify commercial PP to prepare the Co-3DC-rGO/PP separator. The performance of Co-3DC-rGO/PP separator was evaluated in lithium-sulfur batteries (LSBs). SEM images exhibited that a three-dimensional carbon (3DC) skeleton was obtained by corn husk transformation, and the ZIF-67-derived cobalt-decorated carbon dodecahedrons were homogeneously filled into the hierarchical pores of the 3DC structure. TEM images displayed that Co metal nanoparticles can escape from ZIF-67 and scatter on the rGO nano-sheets and 3DC skeleton. Benefitting from the synergy effects of the 3D carbon skeleton, rGO, and Co metal nanoparticles, the electrochemical performance of LSBs with Co-3DC-rGO/PP separator is better than LSBs with commercial PP separator. When tested at 1C, the LSB with Co-3DC-rGO/PP separator presents a high stable reversible capacity of 516.3 mA h g−1 after 500 cycles. This research provides new ideas for the preparation of LSBs separator. [Display omitted] • Co/3D carbon/rGO decorated PP separator was prepared and used in Li-S batteries. • Co/3D carbon/rGO can inhibit the shuttle of lithium polysulfides to the Li anode. • Co/3D carbon/rGO accelerate the conversion of lithium polysulfides to Li2S. • The Li-S battery with Co/3DC/rGO/PP separator delivers excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

• VS 4 nanosheets has been successfully synthesized. • The special nanosheets structure facilitates wetting of electrolyte. • The nanosheets structure is conducive to the diffusion of electron/Na+ in solid phase • The nanosheets VS 4 electrode delivers excellent sodium storage performance. VS 4 with a high theoretical specific capacity is considered as a potential anode material for sodium-ion batteries. In this work, VS 4 nanosheets was firstly synthesized through a simple solvothermal method using N-methyl pyrrolidone (NMP) as the solvent. The unique nanosheets structure is beneficial to the transmission of Na+/electrons and the wetting of electrolyte. Benefiting from the special structure, the prepared VS 4 exhibits satisfactory sodium storage performance, especially the cycle stability at a high current density (534 mA h g-1 after 500 cycles at 1 A g-1) and excellent coulomb efficiency (about 100% since the second cycle). Most importantly, this work provides a feasible and simple method for preparing transition metal sulfides nanosheets, which can be used in energy storage devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Plum blossom-like CoSe 2 /N-doped carbon nanotubes S host was synthesized. • DFT calculation confirms the catalytic performance of CoSe 2 for Li 2 S x conversion. • The plum blossom-like structure is beneficial to the diffusion of electron/Li+. • DFT calculation confirms the chemical adsorption of CoSe 2 to Li 2 S x. • The CoSe 2 /hNCTs/S cathode delivers satisfactory lithium storage performance. Lithium-sulfur batteries (LSBs) have attracted wide attention as one of the most potential secondary batteries in the next generation. However, the low sulfur utilization, serious "shuttle effect", and large volume expansion of the sulfur cathode restrict the performance of LSBs. Here, CoSe 2 decorated hollow N-doped carbon nanotubes (CoSe 2 /hNCTs) were synthesized firstly, and then the CoSe 2 /hNCTs were used as a sulfur host to prepare a multifunctional CoSe 2 /hNCTs/S cathode. DFT calculations confirm that the CoSe 2 not only efficiently adsorbs lithium polysulfides (LiPSs), but also exhibits good catalytic performance for the conversion of LiPSs. SEM and TEM images indicate that the CoSe 2 uniformly disperses on the surface of the polypyrrole nanotube-derived hNCTs, like plum blossoms. The hNCTs with a morphology of plum blossom branches provide a high conductive network and prohibit large volume expansion during the electrochemical process. And the plum petal-like CoSe 2 on the hNCTs surface acts as a catalyst and an efficient polysulfides trap. The CoSe 2 /hNCTs/S cathode delivers a satisfactory lithium storage performance, which presents reversible capacities of 1156 and 640 mA h g−1 at 0.5 and 5C, respectively. Simultaneously, the cathode demonstrates excellent cycle stability with a slow capacity decay rate of 0.069% per cycle in 1000 cycles at 1C rate. This work provides a new idea for constructing composites of transition metal selenides and carbon materials, promoting the practical applications of LSBs. [ABSTRACT FROM AUTHOR]

The crystal density and Mohs hardness of zinc cadmium thiocyanate (ZCTC), ZnCd(SCN)4 have been measured at room temperature. The specific heat of the crystal is 699.5 J mol-1 K-1 at 300 K. The thermal expansion coefficient (TEC) along the a and c axes, respectively, is interpreted on the basis of crystal structure. The thermal decomposition process is characterized by thermogravimetry analysis and differential scanning calorimetry (TGA/DSC). The intermediates and final products of the thermal decomposition were identified by X-ray powder diffraction at room temperature. The high-temperature effect in air on the optical transmission of the crystal was also studied. [Copyright &y& Elsevier]

[Display omitted] • Three mineralization stages existed in sulfide deposits in Tianzuo field. • Sulfide in Tianzuo field is enriched in Fe, Co and Ba but depleted in Cu, Zn and Ni. • Transform fault and episodic hydrothermal event lead to heavy δ34S value. • Pb in sulfide is sourced from leaching of basalts and peridotites by seawater. A newly confirmed hydrothermal sulfide ore hosted by ultramafic rocks was identified in the Tianzuo field on the Southwest Indian Ridge. In this study, detailed mineralogy, geochemistry, and stable isotope analyses were carried out to assess the source origin and mineralization of the Tianzuo field sulfide deposits. The mineralogical examination indicates that the massive sulfides recovered from the seafloor in this area exhibit multi-stage deposition features with four distinct mineralization stages. In terms of geochemistry, the deposit is characterized by high Fe (31.57–44.59 wt%), Co (up to 2400 ppm), and Ba contents (up to 47.89 ppm), and relatively low Cu + Zn (0.17–7.25 wt%) and Ni contents (3.74–30.6 ppm). These results somewhat different from the features of massive sulfides of the ultramafic-hosted ridge in the Atlantic Ocean. The elevated Ba and Co contents presumably reflect a contribution of deep gabbroic intrusions that, together with serpentinization, drove the high-temperature (~335 °C) hydrothermal vent activity in the Tianzuo field. The Co distribution is influenced by high-temperature and high-gradient conditions apart from the basement rock. In contrast, the depletion of Ni suggests that most of the Ni-rich sulfides are concentrated in the deep stockwork mineralization, whereas the low Cu + Zn content indicates a partial influence of the depleted mantle. With regard to isotopic composition, the sulfide in the Tianzuo field shows relatively heavy in situ S isotopic values, which implies that the widely developed transform faults and episodic hydrothermal events allowed cold seawater to repeatedly rinse the entire plumbing system. In comparison, the bulk Pb isotopic composition indicates that Pb in these sulfide deposits is mainly derived from the leaching of basalts and peridotites by seawater. By integrating all of the evidence, we demonstrate that, apart from the basement rock composition, the pervasive transform faults and multistage hydrothermal activity are important factors that affect the composition of the Tianzuo field sulfide. [ABSTRACT FROM AUTHOR]

Cold seep carbonate represents a faithful record of the ancient methane seepage and provides a nonnegligible contribution to the global carbon reservoir. On the western slope of the Northern Okinawa Trough (NOT), a recent seafloor visualized survey has discovered widespread crust of cold seep carbonate. Here we study mineralogy and geochemistry of these authigenic carbonate to investigate source origin and reconstruct its growth history. Mineralogically, the carbonate crusts are mainly composed of micritic aragonite, with botryoidal aragonite, framboidal pyrite, and microcrystalline authigenic gypsum. Petrographic characteristic unambiguously indicates that this carbonate precipitates in relatively open systems due to a considerable rate of sulfate-dependent anaerobic oxidation of methane (AOM). Regarding geochemistry, strongly 13C-depleted carbon isotope values (as low as −56.1‰, V-PDB) demonstrate that the carbon in the carbonate crusts is mainly derived from biogenic methane coupled with AOM. In contrast, the δ18O enrichment (up to +2.7‰, V-PDB) suggests that the fluid flow from which carbonate precipitated is sourced from dissociation of underlying natural gas hydrates. The U–Th ages of authigenic carbonates fall in the timescale of 22.8–55.7 ka BP, consistent with the period of sea-level lowstand in the late Pleistocene. Overall, several lines of evidence of this study indicate that extensive methane was released by gas hydrate decomposition during sea level fall, consequently resulting in the precipitations of carbonate crust in the NOT. Furthermore, the obviously episodic methane seepages led to the constant accretion from the interior to the exterior within the preformed crust, ultimately inducing the carbonate blocks, slabs and crusts to be exposed on the seafloor. The existence of large-scale carbonate crusts represents a good trapper of the later released carbon especially the isotopically light methane from the deep. • Aragonite is the dominated mineral phase in carbonate crust of Okinawa Trough. • Carbonate is sourced from gas hydrate and carbon mainly from biogenic methane. • U–Th age of carbonate crust is within the periods of sea-level lowstand. [ABSTRACT FROM AUTHOR]

Herein, we demonstrate an effective strategy to prepare N and P co-doped carbon nanotubes (NPC) using pyrrole monomer and phytic acid as precursors. Importantly, density functional theory (DFT) and pseudocapacitance contribution calculations certify that the electron mobility and electrochemical kinetics of the carbon nanotubes are enhanced by P-doping. Furthermore, the co-effect of the special hollow nanotubes structure and dual N, P doping endows the NPC with excellent rate performance and long-term cycling stability when it is used as an anode material for sodium ion batteries. Even tested at a high current density of 5000 mA g−1, a high reversible capacity of 180.3 mA h g−1 can be obtained after 3000 cycles for the NPC electrode. • N, P dual-doped carbon nanotubes (NPC) have been successfully synthesized. • DFT calculation is employed to study the electron mobility of the NPC. • The NPC electrode delivers excellent rate performance and long-term cycling stability. [ABSTRACT FROM AUTHOR]

The sluggish redox reaction kinetics and "shuttle effect" of lithium polysulfides (LPSs) impede the advancement of high-performance lithium-sulfur batteries (LSBs). Transition metal phosphides exhibit distinctive polarity, metallic properties, and tunable electron configuration, thereby demonstrating enhanced adsorption and electrocatalytic capabilities towards LPSs. Consequently, they are regarded as exceptional sulfur hosts for LSBs. Moreover, the introduction of a heterogeneous structure can enhance reaction kinetics and expedite the transport of electrons/ions. In this study, a composite of hollow CoP-FeP cubes with heterostructure modified carbon nanotube (CoFeP-CNTs) was fabricated and utilized as sulfur host in advanced LSBs. The presence of carbon nanotubes (CNTs) facilitates enhanced electron and Li + transport. Meanwhile, the active sites within the heterogeneous interface of CoP-FeP suppress the "shuttle effect" and enhance the conversion kinetics of LPSs. Therefore, the CoFeP-CNTs/S electrode exhibited exceptional cycling stability and demonstrated a capacity attenuation of merely 0.051 % per cycle over 600 cycles at 1C. This study presents a highly effective tactic for synthesizing dual-acting transition metal phosphides with heterostructure, which will play a pivotal role in advancing the development of efficient LSBs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

This study aimed to investigate the mechanism of the effect of TREM2 on cognitive function in autistic mice. TREM2 overexpression and knockdown viruses were given to autism spectrum disorder (ASD) mice and BV2 microglia cell line. To assess cognitive performance, all groups of mice took part in the open field, new object recognition, Morris water maze, and three-box social experiments. Double immunofluorescence labeling demonstrated co-localization of LC3II and NeuN. Proteins from the PI3K/Akt/mTOR pathway were identified. In vivo, behavior studies revealed that TREM2 could successfully improve ASD mice's social interaction and cognitive performance. Besides, we discovered that TREM2 could increase autophagy in ASD mice. In vitro, overexpressing TREM2 reduced the expression of PI3K/AKT/mTOR pathway proteins, whereas knocking down TREM2 increased the expression of PI3K/AKT/mTOR pathway proteins. In conclusion, TREM2 could inhibit PI3K/Akt/mTOR signaling pathway, enhance autophagy, and improve the social communication ability and cognitive function of ASD mice.

Background: N 6 -methyladenosine (m 6 A) is a common modification in RNA, crucial for various cellular functions and associated with human diseases. Quantification of m 6 A at single-base resolution is of great significance for exploring its biological roles and related disease research. However, existing analysis techniques, such as polymerase chain reaction (PCR) or loop-mediated isothermal amplification (LAMP), face challenges like the requirement for thermal cycling or intricate primer design. Therefore, it is urgent to establish a simple, non-thermal cycling and highly sensitive assay for m 6 A., Results: Leveraging the inhibitory effect of m 6 A on primer elongation and uncomplicated feature of the isothermal exponential amplification reaction (IEXPAR), we have developed an extension-based IEXPAR (E-IEXPAR). This approach requires just a single extension primer and one template, simplifying the design process in comparison to the more complex primer requirements of the LAMP methods. The reactions are conducted at constant temperatures, therby elimiating the use of thermal cycling that needed in PCR methods. By combining IEXPAR with an extension reaction, E-IEXPAR can identify m 6 A in RNA concentrations as low as 4 fM. We have also introduced a new analytical model to process E-IEXPAR results, which can aid to minimize the impact of unmodified adenine (A) on m 6 A measurements, enabling accurate m 6 A quantification in small mixed samples and cellular RNA specimens., Significance and Novelty: E-IEXPAR streamlines m 6 A detection by eliminating the need for intricate primer design and thermal cycling, which are common in current analytical methods. Its utilization of an extension reaction for the initial identification of m 6 A, coupled with a novel calculation model tailored to E-IEXPAR outcomes, ensures accurate m 6 A selectivity in mixed samples. As a result, E-IEXPAR offers a reliable, straightforward, and potentially economical approach for specifically assaying m 6 A in both biological function studies and clinical research., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The Ledong Sea Area is located on the southwest side of Hainan Island. In recent years, with the development of industrialization and urbanization, the problem of heavy metals in marine sediments has gradually become a global problem, and research on this topic is of great significance for nearshore environmental protection and coastal management. This paper analysed the heavy metal content of 97 surface sediments in the Ledong Sea, indicating unpolluted to moderately polluted and low to moderate risk. Cu, Zn, Hg, Pb, Cr, and Cd are highly correlated, with similar origins, and originate from rivers carrying industrial wastewater, domestic sewage, and weathered material from the parent rocks, which are subsequently redistributed under the action of ocean dynamics. The distribution of Hg is mainly influenced by feed and biological metabolites during the farming process. As originates from rivers carrying large amounts of agricultural pesticide and fertilizer residues., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Background: Non-small cell lung cancer (NSCLC) is a type of lung cancer that occurs in the cells of the respiratory tract, and its development is influenced by the regulation of circular RNAs (circRNAs). However, the role of circRNA carboxypeptidase A4 (circCPA4) in the progression of NSCLC and the underlying mechanism remain relatively clear., Methods: The study utilized both real-time quantitative polymerase chain reaction (RT-qPCR) and western blot techniques to evaluate the levels of circCPA4, microRNA-145-5p (miR-145-5p), alanine, serine, or cysteine-preferring transporter 2 (ASCT2). To assess cell proliferation, cell counting kit-8 (CCK8) and 5-ethynyl-2'-deoxyuridine (EdU) assays were performed. Apoptosis was determined using flow cytometry, while cell migration and invasive capacity were evaluated through transwell and wound-healing assays. Intracellular levels of glutamine, glutamate, and α-KG were measured using specific kits. The relationship between miR-145-5p and circCPA4 or ASCT2 was confirmed using dual-luciferase reporter assay and RNA immunoprecipitation assay., Results: CircCPA4 and ASCT2 RNA levels were elevated, while miR-145-5p was downregulated in both NSCLC tissues and cells. Depletion of circCPA4 significantly inhibited NSCLC cell proliferation, migration, invasion, and intracellular levels of glutamine, glutamate, and α-KG, and promoted apoptosis. Moreover, circCPA4 knockdown delayed tumor growth in vivo. Furthermore, circCPA4 was found to bind to miR-145-5p, thereby regulating the progression of NSCLC in vitro. ASCT2 was also identified as a downstream target of miR-145-5p, and its upregulation rescued the effects of miR-145-5p overexpression on NSCLC cell processes., Conclusion: CircCPA4 knockdown inhibited tumor property of NSCLC cells by modulating the miR-145-5p/ASCT2 axis., (© 2024 The Authors. Thoracic Cancer published by John Wiley & Sons Australia, Ltd.)

Background: Autism spectrum disorder (ASD) encompasses a diverse range of neurodevelopmental disorders, but the precise underlying pathogenesis remains elusive. This study aim to explore the potential mechanism of TREM2 in regulating microglia function in ASD., Materials and Methods: The offspring rat model of ASD was established through prenatal exposure to valproic acid (VPA), and the behavioral symptoms of the ASD model were observed. On postnatal day (PND) 7 and PND 28, the effects of prenatally exposure to VPA on synaptic development and microglia phenotype of offspring rats were observed. Primary microglia were cultured in vitro. Lentivirus and adenovirus were utilized to interfere with TREM2 and overexpress TREM2., Results: Prenatally VPA exposure induced offspring rats to show typical ASD core symptoms, which led to abnormal expression of synapse-related proteins in the prefrontal cortex of offspring rats, changed the phenotype of microglia in offspring rats, promoted the polarization of microglia to pro-inflammatory type, and increased inflammatory response. The experimental results in vitro showed that overexpression of TREM2 could increase the expression of Gephyrin, decrease the content of CD86 protein and increase the content of CD206 protein. In addition, after the expression of TREM2 was interfered, the content of p-P38 MAPK protein increased and the content of p-ELK-1 protein decreased., Conclusion: The protective influence of TREM2 on the VPA-induced ASD model is attributed to its inhibition of the P38 MAPK pathway, this protective effect may be achieved by promoting the polarization of microglia to anti-inflammatory phenotype and improving the neuronal synaptic development., (© 2024. The Author(s).)

We developed a method for quantifying N 6 -methyladenosine at one-nucleotide resolution based on double blocking gap-filling-ligation and cascade isothermal amplification. This proposed method can detect as low as 1 fM target RNA, achieving selectivity up to approximately 100-fold between m 6 A and A, and has been successfully applied to the analysis of m 6 A at specific sites in cell samples.

The target-dependent endonuclease activity (also known as the trans -cleavage activity) of CRISPR-Cas systems has stimulated great interest in the development of nascent sensing strategies for nucleic acid diagnostics. Despite many attempts, the majority of the sensitive CRISPR-Cas diagnostics strategies mainly rely on nucleic acid preamplification, which generally needs complex probes/primers designs, multiple experimental steps, and a longer testing time, as well as introducing the risk of false-positive results. In this work, we propose the CRISPR-Cas-Driven Single Micromotor (Cas-DSM), which can directly detect the nucleic acid targets at a single-molecule level with high specificity. We have demonstrated that the Cas-DSM is a reliable and practical method for the quantitative detection of DNA/RNA in various complex clinical samples as well as in individual cells without any preamplification processes. Due to the excellent features of the CRISPR/Cas system, including constant temperature, simple design, high specificity, and flexible programmability, the Cas-DSM could serve as a simple and universal platform for nucleic acid detection. More importantly, this work will provide a breakthrough for the development of next-generation amplification-free CRISPR/Cas sensing toolboxes.

Oxidative stress contributes to the pathogenesis of various neurodegenerative diseases and induction of the Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) pathway is a validated neuroprotective strategy. Synthetically-derived samples of members of the ribisin class of natural product together with a range of analogues were evaluated for their neuroprotective capacities. Four of the twenty-four compounds tested were found to strongly stimulate antioxidant response element-dependent transcriptional activity in human-derived SH-SY5Y cells. Further, in rat pheochromocytoma PC12 cells and mouse brain cortical cultures these compounds upregulated levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream target gene products, namely heme oxygenase (HO-1) and NAD(P)H quinone reductase 1 (NQO1). Functionally speaking, the compounds conferred protection in these cell models challenged with H 2 O 2 . In silico molecular modeling suggests that certain of the ribisins can dock in the Nrf2-binding Kelch domain in Keap1, while cysteine labeling by biotinylated iodoacetamide suggest that cysteine residues within Keap1 react with the ribisins. It is thus proposed that the most active compounds exert their neuroprotective activities by targeting Keap1, thereby activating Nrf2 and so increasing transactivation of Nrf2-responsive genes that encode for detoxifying and antioxidant enzymes., (© 2022 Wiley-VCH GmbH.)

Objective: To analyze variants of TSC1 and TSC2 genes in a Chinese patient with tuberous sclerosis complex (TSC)., Methods: Peripheral blood samples were collected from the patient and her parents with informed consent. Following extraction of genomic DNA, potential variants of the TSC1 and TSC2 genes was detected by using targeted capture next-generation sequencing (NGS) and Sanger sequencing., Results: The patient was found to harbor a de novo mosaicism variant c.3295_3298delG (Val1100CysfsTer3) of the TSC2 gene, with the proportion of the mutant allele determined as 13.4%, which was confirmed by Sanger sequencing. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the c.3295_3298delG (Val1100CysfsTer3) variant was predicted to be pathogenic (PVS1+PS2+PM2)., Conclusion: The mosaicism heterozygous variant of c.3295_3298delG of the TSC2 gene, as detected by both NGS and Sanger sequencing, probably underlay the TSC2 in this patient.

N 6 -Methyladenosine (m 6 A) is the most frequent post-transcriptional modification in RNA, and it plays a critical role in biological processes. The functions of m 6 A remain largely unexplored due to a lack of highly sensitive methods to quantitatively determine the m 6 A modification fraction at a precise location. Here, we first reveal that T3 DNA ligase has significant selectivity towards the m 6 A modification. On the basis of the new finding, we establish an ultrasensitive quantitation assay for accurately determining m 6 A at one-nucleotide resolution in RNA. With the proposed assay, as low as 4 fM RNA containing m 6 A can be determined and the selectivity is up to 54.1-fold to discriminate m 6 A against unmodified adenosine (A). The sensitivity has been improved about 10 6 -fold so the proposed method can be successfully employed to accurately determine m 6 A in real biological samples, even in low abundance RNA.

Introduction: Cervical cancer is the second leading cause of cancer morbidity and mortality for women around the world. Long non-coding RNAs (lncRNAs) have been investigated as a new class of regulators of cellular processes, such as cell growth, apoptosis, and carcinogenesis. Although downregulation of lncRNA GAS5 in several cancers has been studied, its role in cervical cancer remains unknown. The aim of this study is to investigate the expression, clinical significance and biological role in cervical cancer., Methods: Expression of GAS5 was analyzed in cervical cancer tissues by quantitative Real-time PCR (qRT-PCR). And its association with overall survival of patients was analyzed by statistical analysis. Small interfering RNA (siRNA) was used to suppress GAS5 expression in cervical cancer cells. In vitro assays were performed to further explore the biological functions of GAS5 in cervical cancer., Results: We found that GAS5 expression was markedly downregulated in cervical cancer tissues than in corresponding adjacent normal tissues. Decreased GAS5 expression was significantly correlated with FIGO stage, vascular invasion and lymph node metastasis. Moreover, cervical cancer patients with GAS5 lower expression have shown significantly poorer overall survival than those with higher GAS5 expression. And GAS5 expression was an independent prognostic marker of overall survival in a multivariate analysis. In vitro assays our data indicated that knockdown of GAS5 promoted cell proliferation, migration, and invasion., Conclusions: Our study presents that lncRNA GAS5 is a novel molecule involved in cervical cancer progression, which provide a potential prognostic biomarker and therapeutic target.