Nocardiosis manifests as an opportunistic infection,primarily affecting individuals who are immunocompromised and susceptible to the infection.We present a case study of one patient with nephrotic syndrome and membran...Nocardiosis manifests as an opportunistic infection,primarily affecting individuals who are immunocompromised and susceptible to the infection.We present a case study of one patient with nephrotic syndrome and membranous nephropathy,who underwent treatment with prednisone and cyclosporine in 2016.In early 2017,the patient was diagnosed with a"fungal infection"and discontinued the use of cyclosporine.After one month of anti-infection therapy,a cranial magnetic resonance imaging scan showed multiple abscesses in the right temporal region.The diagnosis of nocardiosis was confirmed based on the presence of metastatic abscess masses,multiple lung and brain lesions,and a positive culture of Nocardia in the drainage.We changed the anti-infection therapy to a combination of trimethoprim-sulfamethoxazole(TMP-SMX),minocycline,and voriconazole.However,the patient experienced a sudden cardiac arrest and subsequently recovered after cardiopulmonary resuscitation.During the five-month follow-up period following the discharge,the patient displayed an enhanced nutritional status and stable renal function.The focal infection ultimately resolved during the subsequent three years.Neuro-infection caused by Nocardia should be considered in immunocompromised patients,and TMP-SMX is the preferred initial therapy;however,because of the high mortality rate,a long-term combination therapy with imipenem,cefotaxime,amikacin,and TMP-SMX is suggested.展开更多
Following the recent report by Dasenbrock-Gammon et al.[Nature 615,244–250(2023)]of near-ambient superconductivity in nitrogendoped lutetium trihydride(LuH_(3-δ)N_(ε)),significant debate has emerged surrounding the...Following the recent report by Dasenbrock-Gammon et al.[Nature 615,244–250(2023)]of near-ambient superconductivity in nitrogendoped lutetium trihydride(LuH_(3-δ)N_(ε)),significant debate has emerged surrounding the composition and interpretation of the observed sharp resistance drop.Here,we meticulously revisit these claims through comprehensive characterization and investigations.We definitively identify the reported material as lutetium dihydride(LuH_(2)),resolving the ambiguity surrounding its composition.Under similar conditions(270–295 K and 1–2 GPa),we replicate the reported sharp decrease in electrical resistance with a 30%success rate,aligning with the observations by Dasenbrock-Gammon et al.However,our extensive investigations reveal this phenomenon to be a novel pressure-induced metal-to-metal transition intrinsic to LuH_(2),distinct from superconductivity.Intriguingly,nitrogen doping exerts minimal impact on this transition.Our work not only elucidates the fundamental properties of LuH_(2)andLuH_(3),but also critically challenges the notion of superconductivity in these lutetium hydride systems.These findings pave the way for future research on lutetium hydride systems,while emphasizing the crucial importance of rigorous verification in claims of ambient-temperature superconductivity.展开更多
A hard problem that hinders the movement of waxy crude oil is wax deposition in oil pipelines.To ensure the safe operation of crude oil pipelines,an accurate model must be developed to predict the rate of wax depositi...A hard problem that hinders the movement of waxy crude oil is wax deposition in oil pipelines.To ensure the safe operation of crude oil pipelines,an accurate model must be developed to predict the rate of wax deposition in crude oil pipelines.Aiming at the shortcomings of the ENN prediction model,which easily falls into the local minimum value and weak generalization ability in the implementation process,an optimized ENN prediction model based on the IRSA is proposed.The validity of the new model was confirmed by the accurate prediction of two sets of experimental data on wax deposition in crude oil pipelines.The two groups of crude oil wax deposition rate case prediction results showed that the average absolute percentage errors of IRSA-ENN prediction models is 0.5476% and 0.7831%,respectively.Additionally,it shows a higher prediction accuracy compared to the ENN prediction model.In fact,the new model established by using the IRSA to optimize ENN can optimize the initial weights and thresholds in the prediction process,which can overcome the shortcomings of the ENN prediction model,such as weak generalization ability and tendency to fall into the local minimum value,so that it has the advantages of strong implementation and high prediction accuracy.展开更多
The lutetium dihydride LuH2is stable at ambient conditions.Here we show that its color undergoes sequential changes from dark blue at ambient pressure to pink at ~2.2 GPa and then to bright red at ~4 GPa upon compress...The lutetium dihydride LuH2is stable at ambient conditions.Here we show that its color undergoes sequential changes from dark blue at ambient pressure to pink at ~2.2 GPa and then to bright red at ~4 GPa upon compression in a diamond anvil cell.Such a pressure-induced color change in LuH2is reversible and it is very similar to that recently reported in the N-doped lutetium hydride [Nature 615,244(2023)].However,our preliminary resistance measurements on LuH2under pressures up to ~7 GPa evidenced no superconductivity down to 1.5 K.展开更多
To clarify the effects of lignin as a biodegradable filler added into the PLA matrix,PLA/lignin composites with or without silane coupling agent ofγ-(2,3-epoxypropoxy)propy trimethoxysilane(KH560)were prepared by a o...To clarify the effects of lignin as a biodegradable filler added into the PLA matrix,PLA/lignin composites with or without silane coupling agent ofγ-(2,3-epoxypropoxy)propy trimethoxysilane(KH560)were prepared by a one-step solvent-free modification method.The effects of KH560 as a compatibilizer on the morphology,chemical structure,crystallization behavior,thermal degradative behavior as well as mechanical strength of the PLA/lignin composites were analyzed in detail.It was found that,after modification by KH560,the fractured surfaces of composites became smooth,suggested sufficient bonding between the lignin and PLA in the composites with KH560 coupling agent molecules.This result further proved by 1H NMR and ATR spectra of the composites that lignin and PLA formed stable chemical bonds with KH560.Due to the toughening effect of KH560,mainly affect the molecular chain mobility,the thermodynamic properties of LG-KH560/PLA composites were all reduced.When compared to the conventional solution modification method of adding silane coupling agents into PLA/lignin,the composites were synthesized via a single-step reactive extrusion modification procedure in this work showed relatively low tensile strength,which mainly because the existence of the free radicals due to coupling agents result in the composite’s deterioration and subsequent weakening of the tensile properties.展开更多
Branch phenotypic traits determine tree crown architecture,which in turn governs leaf display,light interception,and biomass production.Sylleptic and proleptic branches are the obviously different branch phenotypes in...Branch phenotypic traits determine tree crown architecture,which in turn governs leaf display,light interception,and biomass production.Sylleptic and proleptic branches are the obviously different branch phenotypes in the poplar crown.Many studies have focused on the influence of sylleptic branch numbers(SBN)on biomass production,but the research on the influence of proleptic branch phenotypes was only a few.To explore the relationship between proleptic branch traits and biomass generation production in a high-density poplar plantation,we investigated the branch phenotypic traits of three poplar genotypes,all of which have high survival rates in forests(>95%)and significantly different crown architecture and biomass performance in the high-density plantations(1667 stems ha−1).The plantation site was established in 2007.A terrestrial laser scanner was used to measure branch characteristics such as length,angle of origin and termination,and azi-muth angle.A hierarchical cluster analysis performed on branch characteristics showed that SBN,crown depth,and proleptic branch curvature(PBC)were clustered with bio-mass production and leaf area index(LAI).Among all of the monitored traits,PBC played the second most important role in biomass production after SBN and was significantly correlated with SBN,LAI,and biomass production.The positive correlation between PBC and SBN indicated that a larger PBC was associated with more sylleptic branches within the monitored genotypes planted in the high-density plantation,providing greater leaf area and biomass produc-tion.The results of this study will improve the identification of high-production poplar varieties for cultivation in high-density plantations for biofuel production.展开更多
The articular cartilage （AC） can be seen as a biphasic poroelastic material. The cartilage deformation under compression mainly leads to an interstitial fluid flow in the porous solid phase. In this paper, an analyt...The articular cartilage （AC） can be seen as a biphasic poroelastic material. The cartilage deformation under compression mainly leads to an interstitial fluid flow in the porous solid phase. In this paper, an analytical poroelastic model for the AC under laboratorial mechanical testing is developed. The solutions of interstitial fluid pressure and velocity are obtained. The results show the following facts. （i） Both the pressure and fluid velocity amplitudes are proportional to the strain loading amplitude. （ii） Both the amplitudes of pore fluid pressure and velocity in the AC depend more on the loading amplitude than on the frequency. Thus, in order to obtain the considerable fluid stimulus for the AC cell responses, the most effective way is to increase the loading amplitude rather than the frequency. （iii） Both the interstitiM fluid pressure and velocity are strongly affected by permeability variations. This model can be used in experimental tests of the parameters of AC or other poroelastic materials, and in research of mechanotransduction and injury mechanism involved interstitial fluid flow.展开更多
We systematically measure the superconducting(SC)and mixed state properties of high-quality CsV_3 Sb_5 single crystals with T_c-3.5 K.We find that the upper critical field H_(c2)(T)exhibits a large anisotropic ratio o...We systematically measure the superconducting(SC)and mixed state properties of high-quality CsV_3 Sb_5 single crystals with T_c-3.5 K.We find that the upper critical field H_(c2)(T)exhibits a large anisotropic ratio of H_(c2)^(ab)/H_(c2)^c^9 at zero temperature and fitting its temperature dependence requires a minimum two-band effective model.Moreover,the ratio of the lower critical field,H_(c1)^(ab)/H_(c1)^c,is also found to be larger than 1,which indicates that the in-plane energy dispersion is strongly renormalized near Fermi energy.Both H_(c1)(T)and SC diamagnetic signal are found to change little initially below T_c-3.5 K and then to increase abruptly upon cooling to a characteristic temperature of-2.8 K.Furthermore,we identify a two-fold anisotropy of in-plane angular-dependent magnetoresistance in the mixed state.Interestingly,we find that,below the same characteristic T-2.8 K,the orientation of this two-fold anisotropy displays a peculiar twist by an angle of 60°characteristic of the Kagome geometry.Our results suggest an intriguing superconducting state emerging in the complex environment of Kagome lattice,which,at least,is partially driven by electron-electron correlation.展开更多
Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)-induced cytokine storms constitute the primary cause of coronavirus disease 19(COVID-19)progression,severity,criticality,and death.Glucocorticoid and anti-cy...Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)-induced cytokine storms constitute the primary cause of coronavirus disease 19(COVID-19)progression,severity,criticality,and death.Glucocorticoid and anti-cytokine therapies are frequently administered to treat COVID-19,but have limited clinical efficacy in severe and critical cases.Nevertheless,the weaknesses of these treatment modalities have prompted the development of anti-inflammatory therapy against this infection.We found that the broad-spectrum anti-inflammatory agent inosine downregulated proinflammatory interleukin(IL)-6,upregulated anti-inflammatory IL-10,and ameliorated acute inflammatory lung injury caused by multiple infectious agents.Inosine significantly improved survival in mice infected with SARS-CoV-2.It indirectly impeded TANK-binding kinase 1(TBK1)phosphorylation by binding stimulator of interferon genes(STING)and glycogen synthase kinase-3β(GSK3β),inhibited the activation and nuclear translocation of the downstream transcription factors interferon regulatory factor(IRF3)and nuclear factor kappa B(NF-κB),and downregulated IL-6 in the sera and lung tissues of mice infected with lipopolysaccharide(LPS),H1N1,or SARS-CoV-2.Thus,inosine administration is feasible for clinical anti-inflammatory therapy against severe and critical COVID-19.Moreover,targeting TBK1 is a promising strategy for inhibiting cytokine storms and mitigating acute inflammatory lung injury induced by SARS-CoV-2 and other infectious agents.展开更多
Long non-coding RNAs(lncRNAs)are a class of transcripts longer than 200 bp,which have been emerged as essential regulators in numerous biological processes.Black rockfish(Sebastes schlegelii)is an economic fish that w...Long non-coding RNAs(lncRNAs)are a class of transcripts longer than 200 bp,which have been emerged as essential regulators in numerous biological processes.Black rockfish(Sebastes schlegelii)is an economic fish that widely cultured in the coastal areas of China,Japan,and South Korea.With the expansion of aquacultural scale,various pathogens have threatened its industry and reduced its economic values.It has been reported that lncRNA were involved in the immune response and metabolic pathway in teleost,while no study is available on identification and functional analysis of lncRNAs in black rockfish so far.Herein,this study was performed to identify lncRNAs in the intestine of black rockfish after Edwardsiella tarda infection.In our results,a total of 9311 lncRNAs were identified through highthroughput sequencing,and 102 lncRNAs were significantly regulated following challenge,which were predicted to target 3348 mRNAs.Results of Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses of the se target genes showed they were function in catalytic activity,hydrolase activity,defense response and peptidase activity,which involved in metabolic pathways and immune related pathways.In addition,47 lncRNAs and 8 differentially expressed mRNAs(DEmRNAs)showed co-expression at two or more infection time points with metabolism and immunity functions.Moreover,real-time quantitative PCR(qRT-PCR)was performed to verify the reliability of sequencing gene expression analysis results.This research laid the foundation for further investigation of the regulatory roles of lncRNAs in the intestinal immune response of black rockfish.展开更多
The current research of the Q-P and Q-P-T process has been focused on controlling the heating temperature and holding time,or adding alloy elements into the steel to induce precipitation strengthening and improve the ...The current research of the Q-P and Q-P-T process has been focused on controlling the heating temperature and holding time,or adding alloy elements into the steel to induce precipitation strengthening and improve the strength and plasticity of the steel.In this article,based on a quenching-partitioning-tempering(Q-P-T)process combined with a hot deformation technology,a deforming-quenching-partitioning-tempering(D-Q-P-T)process was applied to medium carbon steel.The effect of the heat treatment parameters on the microstructure and mechanical properties of experimental steel under deformation was studied.Through use of a scanning electron microscope(SEM),transmission electron microscopy(TEM)and tensile tests,the optimal heat treatment conditions for realizing high strength and plasticity that meet the safety requirements were obtained.The mechanism for the D-Q-P-T process to improve the strength and plasticity of experimental steel was discussed.A multiphase composite structure of lath martensite and retained austenite was obtained.Compared with the Q-P-T process,use of the D-Q-P-T process can increase the strength of steel by 57.77 MPa and the elongation by 5%.This study proposes a method to improve the strength and plasticity of steel.展开更多
Recently,transition-metal-based kagome metals have aroused much research interest as a novel platform to explore exotic topological quantum phenomena.Here we report on the synthesis,structure,and physical properties o...Recently,transition-metal-based kagome metals have aroused much research interest as a novel platform to explore exotic topological quantum phenomena.Here we report on the synthesis,structure,and physical properties of a bilayer kagome lattice compound V_(3)Sb_(2).The polycrystalline V_(3)Sb_(2) samples were synthesized by conventional solid-state-reaction method in a sealed quartz tube at temperatures below 850℃.Measurements of magnetic susceptibility and resistivity revealed consistently a density-wave-like transition at Tdw≈160 K with a large thermal hysteresis,even though some sample-dependent behaviors were observed presumably due to the different preparation conditions.Upon cooling through Tdw,no strong anomaly in lattice parameters and no indication of symmetry lowering were detected in powder x-ray diffraction measurements.This transition can be suppressed completely by applying hydrostatic pressures of about 1.8 GPa,around which no sign of superconductivity was observed down to 1.5 K.Specific-heat measurements revealed a relatively large Sommerfeld coefficientγ=18.5 mJ·mol^(-1)·K^(-2),confirming the metallic ground state with moderate electronic correlations.Density functional theory calculations indicate that V_(3)Sb_(2) shows a non-trivial topological crystalline property.Thus,our study makes V_(3)Sb_(2) a new candidate of metallic kagome compound to study the interplay between density-wave-order,nontrivial band topology,and possible superconductivity.展开更多
Current induced spin-orbit torque(SOT)switching of magnetization is a promising technology for nonvolatile spintronic memory and logic applications.In this work,we systematically investigated the effect of Ta thicknes...Current induced spin-orbit torque(SOT)switching of magnetization is a promising technology for nonvolatile spintronic memory and logic applications.In this work,we systematically investigated the effect of Ta thickness on the magnetic properties,field-free switching and SOT efficiency in a ferromagnetically coupled Co/Ta/Co Fe B trilayer with perpendicular magnetic anisotropy.We found that both the anisotropy field and coercivity increase with increasing Ta thickness from0.15 nm to 0.4 nm.With further increase of Ta thickness to 0.5 nm,two-step switching is observed,indicating that the two magnetic layers are magnetically decoupled.Measurements of pulse-current induced magnetization switching and harmonic Hall voltages show that the critical switching current density increases while the field-free switching ratio and SOT efficiency decrease with increasing Ta thickness.Both the enhanced spin memory loss and reduced interlayer exchange coupling might be responsible for theβ_(DL)decrease as the Ta spacer thickness increases.The studied structure with the incorporation of a Co Fe B layer is able to realize field-free switching in the strong ferromagnetic coupling region,which may contribute to the further development of magnetic tunnel junctions for better memory applications.展开更多
Influenza viruses are major respiratory pathogens known to infect human and a variety of animals and are widely prevalent worldwide.Genome structure of influenza D virus(IDV)is identical to that of influenza C virus(I...Influenza viruses are major respiratory pathogens known to infect human and a variety of animals and are widely prevalent worldwide.Genome structure of influenza D virus(IDV)is identical to that of influenza C virus(ICV),and phylogenetic analyses suggest that IDV and ICV share a common ancestry and high homology.To date,the prevalence of ICV and IDV in China is unclear,but these viruses represent a potential threat to public health due to cross-species transmission and zoonotic potential.To efficiently monitor ICV and IDV,it is necessary to establish a dual detection method to understand their prevalence and conduct in-depth research.A duplex real-time PCR method for the simultaneous detection of ICV and IDV was developed.TaqMan fluorescent probes and specific primers targeting NP gene of ICV and PB1 gene of IDV were designed.This method exhibited good specificity and sensitivity,and the detection limit reached 1 × 10^(1) copies/pL of plasmid standards of each pathogen.Thirty-one clinical swine samples and 10 clinical cattle samples were analyzed using this method.One positive sample of IDV was detected,and the accuracy of clinical test results was verified by conventional PCR and DNA sequencing.The duplex real-time PCR detection method represents a sensitive and specific tool to detect IG/and IDV,It provides technical support for virus research and clinical diagnosis of ICV and IDV.This information will benefit animal and human health.展开更多
Long-term excessive intake of nitrite(NO_(2)^(-))poses a great threat to human health,needing a simple and fast method to detect NO_(2)-in food.Herein,via a simple and feasible strategy,Mn/Yb/Er triple-doped CeO_(2) n...Long-term excessive intake of nitrite(NO_(2)^(-))poses a great threat to human health,needing a simple and fast method to detect NO_(2)-in food.Herein,via a simple and feasible strategy,Mn/Yb/Er triple-doped CeO_(2) nanozyme(Mn/Yb/Er/CeO_(2))was synthesized for highly sensitive ratiometric detection of nitrite.By doping Mn,Yb,Er into CeO_(2) lattice structure,Mn/Yb/Er/CeO_(2) nanozyme showed enhanced oxidase-like activity,obtaining a higher density of oxygen vacancy and a higher ratio of Ce^(3+)to Ce~(4+)than that of CeO_(2).The 3,3,5,5-tetramethylbenzidine(TMB)can be effectively oxidized by Mn/Yb/Er/CeO_(2) to produce the oxidized TMB(ox TMB),showing a significant absorption signal at 652 nm.Additionally,nitrite can react with ox TMB to produce yellow diazotized ox TMB,which is accompanied by an elevated absorption signal at 445 nm and a decreased absorption signal at 652 nm.Thus,based on the oxidase-mimetic activity of Mn/Yb/Er/CeO_(2) and the diazotization reaction between NO_(2)^(-)and ox TMB,a ratiometric colorimetric assay was established for NO_(2)^(-)detection in food.Furthermore,by integrating Mn/Yb/Er/CeO_(2) with a smartphone,a colorimetric smartphone-sensing platform was successfully fabricated for visualization and quantitative detection of NO_(2)^(-).Notably,this two-detection mode showed excellent sensitivity,selectivity,reliability and practicability in monitoring the NO_(2)^(-)in real samples,impling its great potential for food safety.展开更多
Antimony(Sb) is a toxic metalloid, and its pollution has become a global environmental problem as a result of its extensive use and corresponding Sb-mining activities. The toxicity and mobility of Sb strongly depend o...Antimony(Sb) is a toxic metalloid, and its pollution has become a global environmental problem as a result of its extensive use and corresponding Sb-mining activities. The toxicity and mobility of Sb strongly depend on its chemical speciation. In this review, we summarize the current knowledge on the biogeochemical processes(including emission, distribution,speciation, redox, metabolism and toxicity) that trigger the mobilization and transformation of Sb from pollution sources to the surrounding environment. Natural phenomena such as weathering, biological activity and volcanic activity, together with anthropogenic inputs, are responsible for the emission of Sb into the environment. Sb emitted in the environment can adsorb and undergo redox reactions on organic or inorganic environmental media, thus changing its existing form and exerting toxic effects on the ecosystem. This review is based on a careful and systematic collection of the latest papers during 2010–2017 and our research results, and it illustrates the fate and ecological effects of Sb in the environment.展开更多
基金funded by grants from the National Natural Science Foundation of China(Grant No.81570666)International Society of Nephrology Clinical Research Program(Grant No.18-01-0247)+3 种基金Program of Jiangsu Clinical Research Center(Grant No.BL2014084)Jiangsu Province Key Medical Personnel Project(Grant No.ZDRCA2016002)CKD Anemia Research Foundation from China International Medical Foundation(Grant No.Z-2017-24-2037)Outstanding Young and Middle-aged Talents Support Program of the First Affiliated Hospital of Nanjing Medical University(Jiangsu Province Hospital).
文摘Nocardiosis manifests as an opportunistic infection,primarily affecting individuals who are immunocompromised and susceptible to the infection.We present a case study of one patient with nephrotic syndrome and membranous nephropathy,who underwent treatment with prednisone and cyclosporine in 2016.In early 2017,the patient was diagnosed with a"fungal infection"and discontinued the use of cyclosporine.After one month of anti-infection therapy,a cranial magnetic resonance imaging scan showed multiple abscesses in the right temporal region.The diagnosis of nocardiosis was confirmed based on the presence of metastatic abscess masses,multiple lung and brain lesions,and a positive culture of Nocardia in the drainage.We changed the anti-infection therapy to a combination of trimethoprim-sulfamethoxazole(TMP-SMX),minocycline,and voriconazole.However,the patient experienced a sudden cardiac arrest and subsequently recovered after cardiopulmonary resuscitation.During the five-month follow-up period following the discharge,the patient displayed an enhanced nutritional status and stable renal function.The focal infection ultimately resolved during the subsequent three years.Neuro-infection caused by Nocardia should be considered in immunocompromised patients,and TMP-SMX is the preferred initial therapy;however,because of the high mortality rate,a long-term combination therapy with imipenem,cefotaxime,amikacin,and TMP-SMX is suggested.
基金the National Key Research and Development Program of China(Grant Nos.2022YFA1402301 and 2018YFA0305703)the National Natural Science Foundation of China(Grant No.U2230401)+2 种基金the National Key R&D Program of China(Grant No.2021YFA1400200),the National Natural Science Foundation of China(Grant Nos.12025408 and 11921004)the Strategic Priority Research Program of CAS(Grant No.XDB33000000).
文摘Following the recent report by Dasenbrock-Gammon et al.[Nature 615,244–250(2023)]of near-ambient superconductivity in nitrogendoped lutetium trihydride(LuH_(3-δ)N_(ε)),significant debate has emerged surrounding the composition and interpretation of the observed sharp resistance drop.Here,we meticulously revisit these claims through comprehensive characterization and investigations.We definitively identify the reported material as lutetium dihydride(LuH_(2)),resolving the ambiguity surrounding its composition.Under similar conditions(270–295 K and 1–2 GPa),we replicate the reported sharp decrease in electrical resistance with a 30%success rate,aligning with the observations by Dasenbrock-Gammon et al.However,our extensive investigations reveal this phenomenon to be a novel pressure-induced metal-to-metal transition intrinsic to LuH_(2),distinct from superconductivity.Intriguingly,nitrogen doping exerts minimal impact on this transition.Our work not only elucidates the fundamental properties of LuH_(2)andLuH_(3),but also critically challenges the notion of superconductivity in these lutetium hydride systems.These findings pave the way for future research on lutetium hydride systems,while emphasizing the crucial importance of rigorous verification in claims of ambient-temperature superconductivity.
文摘A hard problem that hinders the movement of waxy crude oil is wax deposition in oil pipelines.To ensure the safe operation of crude oil pipelines,an accurate model must be developed to predict the rate of wax deposition in crude oil pipelines.Aiming at the shortcomings of the ENN prediction model,which easily falls into the local minimum value and weak generalization ability in the implementation process,an optimized ENN prediction model based on the IRSA is proposed.The validity of the new model was confirmed by the accurate prediction of two sets of experimental data on wax deposition in crude oil pipelines.The two groups of crude oil wax deposition rate case prediction results showed that the average absolute percentage errors of IRSA-ENN prediction models is 0.5476% and 0.7831%,respectively.Additionally,it shows a higher prediction accuracy compared to the ENN prediction model.In fact,the new model established by using the IRSA to optimize ENN can optimize the initial weights and thresholds in the prediction process,which can overcome the shortcomings of the ENN prediction model,such as weak generalization ability and tendency to fall into the local minimum value,so that it has the advantages of strong implementation and high prediction accuracy.
基金supported by the National Natural Science Foundation of China (Grant Nos.12025408,11921004,11888101,and 11974029)the Beijing Natural Science Foundation (Grant No.Z190008)+2 种基金the National Key R&D Program of China (Grant Nos.2018YFA0305700 and 2021YFA1400200)the Strategic Priority Research Program of CAS (Grant No.XDB33000000)the CAS Interdisciplinary Innovation Team (Grant No.JCTD-2019-01)。
文摘The lutetium dihydride LuH2is stable at ambient conditions.Here we show that its color undergoes sequential changes from dark blue at ambient pressure to pink at ~2.2 GPa and then to bright red at ~4 GPa upon compression in a diamond anvil cell.Such a pressure-induced color change in LuH2is reversible and it is very similar to that recently reported in the N-doped lutetium hydride [Nature 615,244(2023)].However,our preliminary resistance measurements on LuH2under pressures up to ~7 GPa evidenced no superconductivity down to 1.5 K.
基金funded by the National Key Research and Development Program of China(grant number:2019YFD1101201)the National Natural Science Foundation of China(grant numbers:51773005 and 21905008)the Beijing Natural Science Foundation(grant number:2194071).
文摘To clarify the effects of lignin as a biodegradable filler added into the PLA matrix,PLA/lignin composites with or without silane coupling agent ofγ-(2,3-epoxypropoxy)propy trimethoxysilane(KH560)were prepared by a one-step solvent-free modification method.The effects of KH560 as a compatibilizer on the morphology,chemical structure,crystallization behavior,thermal degradative behavior as well as mechanical strength of the PLA/lignin composites were analyzed in detail.It was found that,after modification by KH560,the fractured surfaces of composites became smooth,suggested sufficient bonding between the lignin and PLA in the composites with KH560 coupling agent molecules.This result further proved by 1H NMR and ATR spectra of the composites that lignin and PLA formed stable chemical bonds with KH560.Due to the toughening effect of KH560,mainly affect the molecular chain mobility,the thermodynamic properties of LG-KH560/PLA composites were all reduced.When compared to the conventional solution modification method of adding silane coupling agents into PLA/lignin,the composites were synthesized via a single-step reactive extrusion modification procedure in this work showed relatively low tensile strength,which mainly because the existence of the free radicals due to coupling agents result in the composite’s deterioration and subsequent weakening of the tensile properties.
基金This work was supported by the National Key Research and Development Program of China(Grant No.2016YFD0600401)the Basic Research Fund of RIF(Grant No.CAFYBB2017ZA001-3)the 12th 5-Year National Science and Technology Support Program(2012BAD01B03).
文摘Branch phenotypic traits determine tree crown architecture,which in turn governs leaf display,light interception,and biomass production.Sylleptic and proleptic branches are the obviously different branch phenotypes in the poplar crown.Many studies have focused on the influence of sylleptic branch numbers(SBN)on biomass production,but the research on the influence of proleptic branch phenotypes was only a few.To explore the relationship between proleptic branch traits and biomass generation production in a high-density poplar plantation,we investigated the branch phenotypic traits of three poplar genotypes,all of which have high survival rates in forests(>95%)and significantly different crown architecture and biomass performance in the high-density plantations(1667 stems ha−1).The plantation site was established in 2007.A terrestrial laser scanner was used to measure branch characteristics such as length,angle of origin and termination,and azi-muth angle.A hierarchical cluster analysis performed on branch characteristics showed that SBN,crown depth,and proleptic branch curvature(PBC)were clustered with bio-mass production and leaf area index(LAI).Among all of the monitored traits,PBC played the second most important role in biomass production after SBN and was significantly correlated with SBN,LAI,and biomass production.The positive correlation between PBC and SBN indicated that a larger PBC was associated with more sylleptic branches within the monitored genotypes planted in the high-density plantation,providing greater leaf area and biomass produc-tion.The results of this study will improve the identification of high-production poplar varieties for cultivation in high-density plantations for biofuel production.
基金Project supported by the National Natural Science Foundation of China(Nos.11632013,11472185,and 11702183)the Natural Science Foundation of Shanxi Province(No.2016021145)+1 种基金the Program for the OIT of Higher Learning Institutions of Shanxi,the State Key Laboratory of Fine Chemicals(No.KF 1511)the Scientific and Technological Innovation Projects of Colleges and Universities in Shanxi Province(No.2017135)
文摘The articular cartilage （AC） can be seen as a biphasic poroelastic material. The cartilage deformation under compression mainly leads to an interstitial fluid flow in the porous solid phase. In this paper, an analytical poroelastic model for the AC under laboratorial mechanical testing is developed. The solutions of interstitial fluid pressure and velocity are obtained. The results show the following facts. （i） Both the pressure and fluid velocity amplitudes are proportional to the strain loading amplitude. （ii） Both the amplitudes of pore fluid pressure and velocity in the AC depend more on the loading amplitude than on the frequency. Thus, in order to obtain the considerable fluid stimulus for the AC cell responses, the most effective way is to increase the loading amplitude rather than the frequency. （iii） Both the interstitiM fluid pressure and velocity are strongly affected by permeability variations. This model can be used in experimental tests of the parameters of AC or other poroelastic materials, and in research of mechanotransduction and injury mechanism involved interstitial fluid flow.
基金Supported by the National Natural Science Foundation of China (Grant Nos.11834016,11888101,12061131005,51771224 and61888102)the National Key Research and Development Projects of China (Grant Nos.2017YFA0303003 and 2018YFA0305800)the Key Research Program and Strategic Priority Research Program of Frontier Sciences of the Chinese Academy of Sciences (Grant Nos.QYZDY-SSW-SLH001,XDB33010200 and XDB25000000)。
文摘We systematically measure the superconducting(SC)and mixed state properties of high-quality CsV_3 Sb_5 single crystals with T_c-3.5 K.We find that the upper critical field H_(c2)(T)exhibits a large anisotropic ratio of H_(c2)^(ab)/H_(c2)^c^9 at zero temperature and fitting its temperature dependence requires a minimum two-band effective model.Moreover,the ratio of the lower critical field,H_(c1)^(ab)/H_(c1)^c,is also found to be larger than 1,which indicates that the in-plane energy dispersion is strongly renormalized near Fermi energy.Both H_(c1)(T)and SC diamagnetic signal are found to change little initially below T_c-3.5 K and then to increase abruptly upon cooling to a characteristic temperature of-2.8 K.Furthermore,we identify a two-fold anisotropy of in-plane angular-dependent magnetoresistance in the mixed state.Interestingly,we find that,below the same characteristic T-2.8 K,the orientation of this two-fold anisotropy displays a peculiar twist by an angle of 60°characteristic of the Kagome geometry.Our results suggest an intriguing superconducting state emerging in the complex environment of Kagome lattice,which,at least,is partially driven by electron-electron correlation.
基金from the Young Elite Scientists Sponsorship Program by CAST(Grant No.:2021-QNRC1-03)the National Key Research and Development Program of China(Grant No.:2020YFC0845400).
文摘Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)-induced cytokine storms constitute the primary cause of coronavirus disease 19(COVID-19)progression,severity,criticality,and death.Glucocorticoid and anti-cytokine therapies are frequently administered to treat COVID-19,but have limited clinical efficacy in severe and critical cases.Nevertheless,the weaknesses of these treatment modalities have prompted the development of anti-inflammatory therapy against this infection.We found that the broad-spectrum anti-inflammatory agent inosine downregulated proinflammatory interleukin(IL)-6,upregulated anti-inflammatory IL-10,and ameliorated acute inflammatory lung injury caused by multiple infectious agents.Inosine significantly improved survival in mice infected with SARS-CoV-2.It indirectly impeded TANK-binding kinase 1(TBK1)phosphorylation by binding stimulator of interferon genes(STING)and glycogen synthase kinase-3β(GSK3β),inhibited the activation and nuclear translocation of the downstream transcription factors interferon regulatory factor(IRF3)and nuclear factor kappa B(NF-κB),and downregulated IL-6 in the sera and lung tissues of mice infected with lipopolysaccharide(LPS),H1N1,or SARS-CoV-2.Thus,inosine administration is feasible for clinical anti-inflammatory therapy against severe and critical COVID-19.Moreover,targeting TBK1 is a promising strategy for inhibiting cytokine storms and mitigating acute inflammatory lung injury induced by SARS-CoV-2 and other infectious agents.
基金Supported by the Young Experts of Taishan Scholars(No.tsqn201909130)the Science and Technology Support Plan for Youth Innovation of Colleges and Universities in Shandong Province(No.2019KJF003)+1 种基金the“First Class Fishery Discipline”Program in Shandong Province,a special talent program“One Matter One Decision(Yi Shi Yi Yi)”Program in Shandong Province,Chinathe Breeding Plan of Shandong Provincial Qingchuang Research Team(2019)。
文摘Long non-coding RNAs(lncRNAs)are a class of transcripts longer than 200 bp,which have been emerged as essential regulators in numerous biological processes.Black rockfish(Sebastes schlegelii)is an economic fish that widely cultured in the coastal areas of China,Japan,and South Korea.With the expansion of aquacultural scale,various pathogens have threatened its industry and reduced its economic values.It has been reported that lncRNA were involved in the immune response and metabolic pathway in teleost,while no study is available on identification and functional analysis of lncRNAs in black rockfish so far.Herein,this study was performed to identify lncRNAs in the intestine of black rockfish after Edwardsiella tarda infection.In our results,a total of 9311 lncRNAs were identified through highthroughput sequencing,and 102 lncRNAs were significantly regulated following challenge,which were predicted to target 3348 mRNAs.Results of Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses of the se target genes showed they were function in catalytic activity,hydrolase activity,defense response and peptidase activity,which involved in metabolic pathways and immune related pathways.In addition,47 lncRNAs and 8 differentially expressed mRNAs(DEmRNAs)showed co-expression at two or more infection time points with metabolism and immunity functions.Moreover,real-time quantitative PCR(qRT-PCR)was performed to verify the reliability of sequencing gene expression analysis results.This research laid the foundation for further investigation of the regulatory roles of lncRNAs in the intestinal immune response of black rockfish.
基金Supported by Regional Joint Funds of National Natural Science Foundation of China(Grant No.U20A20289).
文摘The current research of the Q-P and Q-P-T process has been focused on controlling the heating temperature and holding time,or adding alloy elements into the steel to induce precipitation strengthening and improve the strength and plasticity of the steel.In this article,based on a quenching-partitioning-tempering(Q-P-T)process combined with a hot deformation technology,a deforming-quenching-partitioning-tempering(D-Q-P-T)process was applied to medium carbon steel.The effect of the heat treatment parameters on the microstructure and mechanical properties of experimental steel under deformation was studied.Through use of a scanning electron microscope(SEM),transmission electron microscopy(TEM)and tensile tests,the optimal heat treatment conditions for realizing high strength and plasticity that meet the safety requirements were obtained.The mechanism for the D-Q-P-T process to improve the strength and plasticity of experimental steel was discussed.A multiphase composite structure of lath martensite and retained austenite was obtained.Compared with the Q-P-T process,use of the D-Q-P-T process can increase the strength of steel by 57.77 MPa and the elongation by 5%.This study proposes a method to improve the strength and plasticity of steel.
基金the National Key R&D Program of China(Grant Nos.2018YFA0305700 and 2018YFA0305800)the National Natural Science Foundation of China(Grant Nos.12025408,11874400,11834016,11921004,11888101,and 11904391)+3 种基金the Beijing Natural Science Foundation,China(Grant No.Z190008)the Strategic Priority Research Program and Key Research Program of Frontier Sciences of Chinese Academy of Sciences(CAS)(Grant Nos.XDB25000000,XDB33000000 and QYZDBSSW-SLH013)the CAS Interdisciplinary Innovation Team(Grant No.JCTD-201-01)supported by the U.S.Department of Energy,Office of Science,Basic Energy Sciences,Materials Sciences and Engineering Division。
文摘Recently,transition-metal-based kagome metals have aroused much research interest as a novel platform to explore exotic topological quantum phenomena.Here we report on the synthesis,structure,and physical properties of a bilayer kagome lattice compound V_(3)Sb_(2).The polycrystalline V_(3)Sb_(2) samples were synthesized by conventional solid-state-reaction method in a sealed quartz tube at temperatures below 850℃.Measurements of magnetic susceptibility and resistivity revealed consistently a density-wave-like transition at Tdw≈160 K with a large thermal hysteresis,even though some sample-dependent behaviors were observed presumably due to the different preparation conditions.Upon cooling through Tdw,no strong anomaly in lattice parameters and no indication of symmetry lowering were detected in powder x-ray diffraction measurements.This transition can be suppressed completely by applying hydrostatic pressures of about 1.8 GPa,around which no sign of superconductivity was observed down to 1.5 K.Specific-heat measurements revealed a relatively large Sommerfeld coefficientγ=18.5 mJ·mol^(-1)·K^(-2),confirming the metallic ground state with moderate electronic correlations.Density functional theory calculations indicate that V_(3)Sb_(2) shows a non-trivial topological crystalline property.Thus,our study makes V_(3)Sb_(2) a new candidate of metallic kagome compound to study the interplay between density-wave-order,nontrivial band topology,and possible superconductivity.
基金Project supported by the‘Pioneer’and‘Leading Goose’Research and Development Program of Zhejiang Province,China(Grant No.2022C01053)the National Natural Science Foundation of China(Grant Nos.11874135,12104119+2 种基金12004090)Key Research and Development Program of Zhejiang Province,China(Grant No.2021C01039)Natural Science Foundation of Zhejiang Province,China(Grant Nos.LQ20F040005 and LQ21A050001)。
文摘Current induced spin-orbit torque(SOT)switching of magnetization is a promising technology for nonvolatile spintronic memory and logic applications.In this work,we systematically investigated the effect of Ta thickness on the magnetic properties,field-free switching and SOT efficiency in a ferromagnetically coupled Co/Ta/Co Fe B trilayer with perpendicular magnetic anisotropy.We found that both the anisotropy field and coercivity increase with increasing Ta thickness from0.15 nm to 0.4 nm.With further increase of Ta thickness to 0.5 nm,two-step switching is observed,indicating that the two magnetic layers are magnetically decoupled.Measurements of pulse-current induced magnetization switching and harmonic Hall voltages show that the critical switching current density increases while the field-free switching ratio and SOT efficiency decrease with increasing Ta thickness.Both the enhanced spin memory loss and reduced interlayer exchange coupling might be responsible for theβ_(DL)decrease as the Ta spacer thickness increases.The studied structure with the incorporation of a Co Fe B layer is able to realize field-free switching in the strong ferromagnetic coupling region,which may contribute to the further development of magnetic tunnel junctions for better memory applications.
基金This work was financially supported by the National Key Research and Development Program of China(2017YFD0500101)the Fundamental Research Funds for the Central Universities(Y0201900459).
文摘Influenza viruses are major respiratory pathogens known to infect human and a variety of animals and are widely prevalent worldwide.Genome structure of influenza D virus(IDV)is identical to that of influenza C virus(ICV),and phylogenetic analyses suggest that IDV and ICV share a common ancestry and high homology.To date,the prevalence of ICV and IDV in China is unclear,but these viruses represent a potential threat to public health due to cross-species transmission and zoonotic potential.To efficiently monitor ICV and IDV,it is necessary to establish a dual detection method to understand their prevalence and conduct in-depth research.A duplex real-time PCR method for the simultaneous detection of ICV and IDV was developed.TaqMan fluorescent probes and specific primers targeting NP gene of ICV and PB1 gene of IDV were designed.This method exhibited good specificity and sensitivity,and the detection limit reached 1 × 10^(1) copies/pL of plasmid standards of each pathogen.Thirty-one clinical swine samples and 10 clinical cattle samples were analyzed using this method.One positive sample of IDV was detected,and the accuracy of clinical test results was verified by conventional PCR and DNA sequencing.The duplex real-time PCR detection method represents a sensitive and specific tool to detect IG/and IDV,It provides technical support for virus research and clinical diagnosis of ICV and IDV.This information will benefit animal and human health.
基金supported by the National Natural Science Foundation of China(Nos.22004111 and 21974125)the Tackle Key Problems in Science and Technology Project of Henan Province,China(No.222102310386)+3 种基金China Postdoctoral Science Foundation(No.2020M682327)Henan Postdoctoral Foundation(No.202002009)Program for Innovative Research Team(in Science and Technology)in University of Henan Province(No.22TRTSTHN002)Excellent Youth Foundation of Henan Scientific Committee(No.232300421021)。
文摘Long-term excessive intake of nitrite(NO_(2)^(-))poses a great threat to human health,needing a simple and fast method to detect NO_(2)-in food.Herein,via a simple and feasible strategy,Mn/Yb/Er triple-doped CeO_(2) nanozyme(Mn/Yb/Er/CeO_(2))was synthesized for highly sensitive ratiometric detection of nitrite.By doping Mn,Yb,Er into CeO_(2) lattice structure,Mn/Yb/Er/CeO_(2) nanozyme showed enhanced oxidase-like activity,obtaining a higher density of oxygen vacancy and a higher ratio of Ce^(3+)to Ce~(4+)than that of CeO_(2).The 3,3,5,5-tetramethylbenzidine(TMB)can be effectively oxidized by Mn/Yb/Er/CeO_(2) to produce the oxidized TMB(ox TMB),showing a significant absorption signal at 652 nm.Additionally,nitrite can react with ox TMB to produce yellow diazotized ox TMB,which is accompanied by an elevated absorption signal at 445 nm and a decreased absorption signal at 652 nm.Thus,based on the oxidase-mimetic activity of Mn/Yb/Er/CeO_(2) and the diazotization reaction between NO_(2)^(-)and ox TMB,a ratiometric colorimetric assay was established for NO_(2)^(-)detection in food.Furthermore,by integrating Mn/Yb/Er/CeO_(2) with a smartphone,a colorimetric smartphone-sensing platform was successfully fabricated for visualization and quantitative detection of NO_(2)^(-).Notably,this two-detection mode showed excellent sensitivity,selectivity,reliability and practicability in monitoring the NO_(2)^(-)in real samples,impling its great potential for food safety.
基金supported by the National Natural Science Foundation of China (Nos.21477008,21677014,U1706217)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (No.51721093)the Interdiscipline Research Funds of Beijing Normal University (No.312231103)
文摘Antimony(Sb) is a toxic metalloid, and its pollution has become a global environmental problem as a result of its extensive use and corresponding Sb-mining activities. The toxicity and mobility of Sb strongly depend on its chemical speciation. In this review, we summarize the current knowledge on the biogeochemical processes(including emission, distribution,speciation, redox, metabolism and toxicity) that trigger the mobilization and transformation of Sb from pollution sources to the surrounding environment. Natural phenomena such as weathering, biological activity and volcanic activity, together with anthropogenic inputs, are responsible for the emission of Sb into the environment. Sb emitted in the environment can adsorb and undergo redox reactions on organic or inorganic environmental media, thus changing its existing form and exerting toxic effects on the ecosystem. This review is based on a careful and systematic collection of the latest papers during 2010–2017 and our research results, and it illustrates the fate and ecological effects of Sb in the environment.
