Pressure-Tuned Intrinsic Anomalous Hall Conductivity in Kagome Magnets RV_(6)Sn_(6)(R=Gd,Tb)

Exploration of exotic phenomena in magnetic topological systems is at the frontier of condensed matter physics,holding a significant promise for applications in topological spintronics.However,complex magnetic structures carrying nontrivial topological properties hinder its progresses.Here,we investigate the pressure effect on the novel topological kagome magnets GdV_(6)Sn_(6) and TbV_(6)Sn_(6) to dig out the interplay between magnetic Gd/Tb layers and nonmagnetic V-based kagome sublattice.The pressure-tuned magnetic transition temperature Tm in both the compounds exhibit a turning point at the critical pressure P_(c),accompanied with a sign reversal in anomalous Hall effect(AHE).The separation of intrinsic and extrinsic contributions using the Tian-Ye-Jin scaling model suggests that the intrinsic mechanism originating from the electronic Berry curvature holds the priority in the competition with extrinsic mechanism in AHE.The above-mentioned findings can be attributed to the combined effect of pressure-tuned band topology and magnetic interaction in segregated layers.Our results provide a practical route to design and manipulate the intrinsic AHE in magnetic topological materials.

Bacterial droplet-based single-cell RNA-seq reveals antibiotic-associated heterogeneous cellular states

We introduce BacDrop, a highly scalable technology for bacterial single-cell RNA sequencing that has overcome manychallenges hindering the development of scRNA-seq in bacteria. BacDrop can be applied to thousands to millions of cells fromboth gram-negative and gram-positive species. It features universal ribosomal RNA depletion and combinatorial barcodes thatenable multiplexing and massively parallel sequencing. We applied BacDrop to study Klebsiella pneumoniae clinical isolates andto elucidate their heterogeneous responses to antibiotic stress. In an unperturbed population presumed to be homogeneous, wefound within-population heterogeneity largely driven by the expression of mobile genetic elements that promote the evolution ofantibiotic resistance. Under antibiotic perturbation, BacDrop revealed transcriptionally distinct subpopulations associated withdifferent phenotypic outcomes including antibiotic persistence. BacDrop thus can capture cellular states that cannot be detectedby bulk RNA-seq, which will unlock new microbiological insights into bacterial responses to perturbations and larger bacterialcommunities such as the microbiome.

Perovskite/organic tandem solar cells

In recent years,the power conversion efficiency(PCE)for single-junction perovskite solar cells(PSCs)[1,2]has reached 25.7%,approaching the Shockley-Queisser limit(S-Q limit).Further enhancing efficiency is challenging.Tandem solar cells offer an effective way to further increase the efficiency beyond S-Q limit.Currently,perovskite/silicon tandem solar cells(TSCs)[3−5]have achieved a PCE of 31.3%[6].However,the complicated preparation processes and high cost hinder their commercialization application.In contrast,thin-film perovskite/organic TSCs have the advantages of solution processability,low cost,and flexibility,making them to be promising candidates for the next-generation photovoltaic technology.

Mechanical pressing method for making high-quality perovskite single crystals

Halide perovskites show excellent photovoltaic properties[1−4].However,the preparation of high-quality perovskite crystals remains a great challenge,which limits their applications.Perovskite materials applied to photodetectors mainly include polycrystalline thin films and single crystals.Traditional solution methods are used to prepare polycrystalline thin films,and the films are full of defects such as voids and grain boundaries[5−7].Compared to polycrystalline thin films,perovskite single crystals possess high crystallinity and low defect density[8−10].Photodetectors based on perovskite single crystals exhibit excellent performance[11].However,the size limitation of single crystals hinders their application in photodetectors[12].

On the Factors Hindering Chinese College Students＇ English Reading and Possible Strategies

Chinese college students reading in a foreign language seem to read with less understanding and at a considerably slower speed. The factors that hinder Chinese college students' English reading were analyzed at the lexical level, the syntactic level,and the discourse level. And then, several reading strategies were recommended to overcome such reading difficulties.

SYNTHESIS AND CHARACTERIZATION OF NEW STABILIZERS WITH OPTIMAL MOLECULAR WEIGHT

Over 2 x 10(8) tons of polymers are produced every year, and a large portion of polymers faces the degradation problem. There are many effective methods to protect polymers against degradation and the addition of stabilizers to polymer remains the most convenient and effective way of enhancing polymer life and performance. In this article, a series of effective stabilizers with optimal molecular weight (MW), including common, monomeric and polymeric stabilizers (antioxidant and light stabilizer) were synthesized using isocyanation, controlled isocyanation, hydrosilylation, epoxide addition, macroreaction of stabilizing functional compounds and polymerization of monomeric stabilizers. The structure and performance of these new stabilizers were characterized by using IR, NMR, MS, UV-spectra, XPS and elemental analysis. The current development of stabilizer synthesis was also reviewed.

COPOLYMERIZATION OF PROPYLENE WITH HINDERED PIPERIDINE MONOMER OVER A HIGH ACTIVITY SUPPORTED ZIEGLER-NATTA CATALYST

Copolymerization of propylene and hindered piperidine monomers was carried out over a high activity supported Ziegler-Natta catalyst, using Al(C2H5)(3) as cocatalyst. Factors which affect the copolymerization were studied, The copolymers exhibited high light stability without adding extra light stabilizers. A self-stabilized polypropylene was prepared.

Sphingosine-1-phosphate hinders the osteogenic differentiation of dental pulp stem cells in association with AKT signaling pathways

Sphingosine-1-phosphate(S1P)is an important lipid mediator that regulates a diverse range of intracellular cell signaling pathways that are relevant to tissue engineering and regenerative medicine.However,the precise function of S1P in dental pulp stem cells(DPSCs)and its osteogenic differentiation remains unclear.We here investigated the function of S1P/S1P receptor(S1PR)-mediated cellular signaling in the osteogenic differentiation of DPSCs and clarified the fundamental signaling pathway.Our results showed that S1P-treated DPSCs exhibited a low rate of differentiation toward the osteogenic phenotype in association with a marked reduction in osteogenesis-related gene expression and AKT activation.Of note,both S1PR1/S1PR3 and S1PR2 agonists significantly downregulated the expression of osteogenic genes and suppressed AKT activation,resulting in an attenuated osteogenic capacity of DPSCs.Most importantly,an AKT activator completely abrogated the S1P-mediated downregulation of osteoblastic markers and partially prevented S1P-mediated attenuation effects during osteogenesis.Intriguingly,the pro-inflammatory TNF-αcytokine promoted the infiltration of macrophages toward DPSCs and induced S1P production in both DPSCs and macrophages.Our findings indicate that the elevation of S1P under inflammatory conditions suppresses the osteogenic capacity of the DPSCs responsible for regenerative endodontics.

SYNTHESIS OF NOVEL BI-FUNCTIONAL COPOLYMER BEARING STERICALLY HINDERED PHENOL AND HINDERED AMINE GROUPS VIA RING-OPENING METATHESIS POLYMERIZATION

Norbornene derivatives exo,endo-2-[2-(3,5-di-tert-butyl-4-hydroxyphenoxy)-acetoxy]methyl-5-norbornene(M1) and 3,3,5,5-tetramethyl-4-piperidinyl 5-norbornene-exo,endo-2-carboxylate(M2)were synthesized and polymerized by RuCl_2(=CHPh)(PCy_3)_2 to prepare a novel kind of bi-functional polymer bearing sterically hindered phenol(SHP)and hindered amine(HLAS)groups via ring-opening metathesis polymerization(ROMP).The resulting copolymers were characterized by gel permeation chromatography(GPC),~1H-NMR and differen...

Embracing the era of neuromorphic computing

In recent years,deep learning has made tremendous achievements in computer vision,natural language processing,man-machine games and so on,where artificial intelligence can reach or go beyond the level of human beings.However,behind so many glories,some serious challenges exist in the bottom hardware,hindering the further development of Artificial Intelligence.

Chrysanthemum CmWRKY53 negatively regulates the resistance of chrysanthemum to the aphid Macrosiphoniella sanborni

Chrysanthemum is frequently attacked by aphids,which greatly hinders the growth and ornamental value of this plant species.WRKY transcription factors play an important role in the response to biotic stresses such as pathogen and insect stresses.Here,chrysanthemum CmWRKY53 was cloned,and its expression was induced by aphid infestation.To verify the role of CmWRKY53 in resistance to aphids,CmWRKY53 transgenic chrysanthemum was generated.CmWRKY53 was found to mediate the susceptibility of chrysanthemum to aphids.The expression levels of secondary metabolite biosynthesis genes,such as peroxidase-and polyphenol oxidase-encoding genes,decreased in CmWRKY53-overexpressing(CmWRKY53-Oe)plants but dramatically increased in chimeric dominant repressor(CmWRKY53-SRDX)plants,suggesting that CmWRKY53 contributes to the susceptibility of chrysanthemum to aphids,possibly due to its role in the regulation of secondary metabolites.

Corrosion Mechanism of E-glass of Chemical Resistance Glass Fiber in Acid Environment

The corrosion of ECR glass fiber was investigated by the analysis methods of weight loss ratio under different acids and at various durations.Weight loss,leaching of cations,and surface composition of ECR glass fiber were analyzed.The corrosion mechanism of ECR glass fiber in acid environment was also discussed.The experimental results showed that the corrosion degree of ECR glass fiber in different acids obeyed the order： HNO3〉H2SO4〉HCl.The acid effects on corrosion of ECR glass fiberis were totally different.Hydrochloric acid mainly destroyed the network structure of [AlO4],while sulfuric acid and nitric acid mainly destroyed the structure of [SiO4].The acid resistance of ECR glass fiber is much better than that of E glass fiber due to the generation of intermediate product silicic acid gel Si（OH）4 during ion exchange.It can adhere to the glass surface to form a thin film and hinder the proceeding of corrosion.

Importance of genetic data from type specimens:The questionable type locality of southern white-cheeked gibbon,Nomascus siki(Delacour,1951)

DEAR EDITOR,Many historical descriptions of new species have included vague or inaccurate information about the type locality.This can lead to confusion in the study of the species and their geographic distributions,thereby hindering conservation efforts.One such example is the southern white-cheeked gibbon(Nomascus siki(Delacour,1951)).The type locality is given as Thua Luu in central Vietnam,which is located within the range of another crested gibbon species(N.annamensis)and more than 200 km south of the known range of N.siki.To investigate the problematic type locality of N.siki,we sequenced the mitochondrial genome of the holotype and compared its cytochrome b gene sequence to those of other georeferenced crested gibbon samples.

SYNTHESIS AND LIGHTFASTNESS PROPERTIES OF DYES CONTAINING HINDERED PIPERIDINE RESIDUES AS INTERNAL STABILIZING GROUPS

The representative azo and anthraquinone dyes containing an insulated hindered piperidinegroup were synthesized.The effect of these pendent groups on lightfastness properties of the dyeswas studied,both in ethyl acetate solution and on cellulose acetate and polyester films.The differ-ent trend of fading rates of azo dyes and anthraquinone dyes in solution and on substrates suggestsdifferent fading mechanisms operating in each case.

Chromosome-level genome assembly of the Chinese longsnout catfish Leiocassis longirostris

The Chinese longsnout catfish(Leiocassis longirostris Günther)is one of the most economically important freshwater fish in China.As wild populations have declined sharply in recent years,it is also a valuable model for research on sexual dimorphism,comparative biology,and conservation.However,the current lack of high-quality chromosome-level genome information for the species hinders the advancement of comparative genomic analysis and evolutionary studies.Therefore,we constructed the first high-quality chromosomelevel reference genome for L.longirostris.The total genome was 703.19 Mb,with 389 contigs and contig N50 length of 4.29 Mb.Using high-throughput chromosome conformation capture(Hi-C)data,the genome sequences(685.53 Mb)were scaffolded into 26 chromosomes ranging from 17.36 to 43.97 Mb,resulting in a chromosomal anchoring rate for the genome of 97.44%.In total,23708 protein-coding genes were identified in the genome.Phylogenetic analysis indicated that L.longirostris and its closest related species P.fulvidraco diverged approximately 26.6 million years ago.This highquality reference genome of L.longirostris should pave the way for future genomic comparisons and evolutionary research.

EFFECTS OF MOLECULE AGGREGATION STATE OF HINDERED PHENOL ON DYNAMIC MECHANICAL PROPERTIES OF CHLORINATED POLYETHYLENE

Hindered phenol compound 3,9-bis{1,1-dimethyl-2[β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl}- 2,4,8,10-tetraoxaspiro[5,5]-undecane (AO-80) is a polymorphous material with different physical structures. The initial AO- 80 is highly crystalline, whereas AO-80 obtained by cooling from its molten state is an amorphous material. Annealing treatment below the melting point of AO-80 results in structural development. The mixture of chlorinated polyethylene (CPE) and vitrified AO-80 particles exhibits a dramatic change in the dynamic mechanical properties during heat treatment at 130'C. This change can be attributed to the decomposition of the vitrified AO-80 particles and the hybridization of two constituents. The vitrified AO-80 particles can crystallize again in a CPE matrix by annealing at 100'C, but this crystal is different from that of the initial AO-80 in its microstructure. In addition, the incorporation of CPE chains caused a dramatic increase in the modulus. As a result, the AO-80 crystal particles that contain some CPE chains act as multifunctional cross- links and the CPE/AO-80 hybrid was found to be a new type of elastomer.

Effect of Photostablizers on Surface Color and Mechanical Property of Wood-flour/HDPE Composites after Weathering

The effects of photostabilizers of ultraviolet absorbers （UVA）, hindered amine light stabilizer （HALS） and pigment on surface color change and mechanical properties of weathered wood-flour/ polyethylene （HDPE） composites were investigated. After being added UVA with high UV absorbance, the WPC exhibites better ability to resist color fading and mechanical property loss. High molecular weight HALS is found to be the most effective in controlling long term fading and yellowing changes. Pigments cover the composites for remaining the original color after weathering regardless of less contribution to mechanical property. Addition of photostabilizer and pigment together show great synergism in decreasing color fading and flexural property loss.

Effects of the Molybdenum Oxide/Metal Anode Interfaces on Inverted Polymer Solar Cells

Inverted polymer solar cells with molybdenum oxide(MoO_(3))as an anode buffer layer and different metals(Al or Ag)as anodes are studied.It is found that the inverted cell with a top Ag anode demonstrates enhanced charge collection and higher power conversion efficiency(PCE)compared to the cell with a top Al anode.An 18%increment of PCE is obtained by replacing Al with Ag as the top anode.Further studies show that an interfacial dipole pointing from MoO_(3) to Al is formed at MoO_(3)/Al interfaces due to electron transfer from Al to MoO_(3) while this phenomenon cannot be observed at MoO_(3)/Ag interfaces.It is speculated that the electric field at the MoO_(3)/Al interface would hinder hole extraction,and hence reduce the short-circuit current.

Perovskite films for X-ray detection

X-ray detection is widely used in research[1−3],product in-spection[4],nuclear station,and medical imaging.Si[5],α-Se[6],PbI2[7],and CdZnTe[8]are conventional semiconductors,and some problems limit their applications.For instance,Si andα-Se have low stopping power for X-ray[8],which hinders their application in high-energy range over 50 keV.Moreover,the complicated preparation,high operating voltage,and high fab-rication cost of these materials are the negative issues.