Meningeal lymphatic vessels form a relationship between the nervous system and periphery, which is relevant in both health and disease. Meningeal lymphatic vessels not only play a key role in the drainage of brain met...Meningeal lymphatic vessels form a relationship between the nervous system and periphery, which is relevant in both health and disease. Meningeal lymphatic vessels not only play a key role in the drainage of brain metabolites but also contribute to antigen delivery and immune cell activation. The advent of novel genomic technologies has enabled rapid progress in the characterization of myeloid and lymphoid cells and their interactions with meningeal lymphatic vessels within the central nervous system. In this review, we provide an overview of the multifaceted roles of meningeal lymphatic vessels within the context of the central nervous system immune network, highlighting recent discoveries on the immunological niche provided by meningeal lymphatic vessels. Furthermore, we delve into the mechanisms of crosstalk between meningeal lymphatic vessels and immune cells in the central nervous system under both homeostatic conditions and neurodegenerative diseases, discussing how these interactions shape the pathological outcomes. Regulation of meningeal lymphatic vessel function and structure can influence lymphatic drainage, cerebrospinal fluid-borne immune modulators, and immune cell populations in aging and neurodegenerative disorders, thereby playing a key role in shaping meningeal and brain parenchyma immunity.展开更多
The East Asia(or Physospermopsis) clade was recognized in previous molecular phylogenetic investigations into the higher-level relationships of Apiaceae subfamily Apioideae. The composition of this clade, the phylogen...The East Asia(or Physospermopsis) clade was recognized in previous molecular phylogenetic investigations into the higher-level relationships of Apiaceae subfamily Apioideae. The composition of this clade, the phylogenetic relationships among its constituent taxa, and the placement of species previously determined to be problematic have yet to be resolved. Herein, nr DNA ITS sequences were obtained for150 accessions of Apioideae, representing species whose distributions are in East Asia or genera having one or more species included within the East Asia clade. These data, along with published ITS sequences from other Apioideae(for 3678 accessions altogether), were subjected to maximum likelihood and Bayesian inference analyses. The results show that the East Asia clade contains representatives of 11currently recognized genera: Hansenia, Hymenolaena, Keraymonia, Sinolimprichtia, Acronema, Hymenidium, Physospermopsis, Pimpinella, Sinocarum, Tongoloa, and Trachydium. However, the latter seven genera have members falling outside of the East Asia clade, including the generic types of all except Tongoloa. Within the clade, the species comprising these seven genera are widely intermingled, greatly increasing confusion among relationships than previously realized. The problematic species Physospermopsis cuneata is confirmed as falling within the East Asia clade, whereas P. rubrinervis allies with the generic type in tribe Pleurospermeae. Physospermopsis kingdon-wardii is confirmed as a member of the genus Physospermopsis, whereas the generic attributions of P. cuneata and Tongoloa stewardii remain unclear. Two species of Sinocarum(S. filicinum and S. wolffianum) are transferred into the genus Meeboldia. This is the most comprehensive molecular phylogenetic investigation of the East Asia clade to date, and while the results increase systematic understanding of the clade, they also highlight the need for further studies of one of the most taxonomically intractable groups in Apioideae.展开更多
Efficient and convenient treatment of industrial dyeing wastewater is of great significance to guarantee human and animal health.This work presented the enhanced catalytic activity at pH 3.0 of laccase immobilized on ...Efficient and convenient treatment of industrial dyeing wastewater is of great significance to guarantee human and animal health.This work presented the enhanced catalytic activity at pH 3.0 of laccase immobilized on amino-functionalized ZnFe_(2)O_(4) nanoparticles(ZnFe_(2)O_(4)-laccase)and its application for the degradation of textile dyes.Due to the existence of a large number of oxygen vacancies on the surface of the ZnFe_(2)O_(4) nanoparticles,negative ions accumulated on the magnetic carriers,which resulted in a harsh optimal pH value of the ZnFe_(2)O_(4)-laccase.Laccase activity assays revealed that the ZnFe_(2)O_(4)-laccase possessed superior pH and thermal stabilities,excellent reusability,and noticeable organic solvent tolerance.Meanwhile,the ZnFe_(2)O_(4) laccase presented efficient and sustainable degradation of high concentrations of textile dyes.The initial decoloration efficiencies of malachite green(MG),brilliant green(BG),azophloxine,crystal violet(CV),reactive blue 19(RB19),and procion red MX-5B were approximately 99.1%,95.0%,93.3%,87.4%,86.1%,and 85.3%,respectively.After 10 consecutive reuses,the degradation rates of the textile dyes still maintained about 98.2%,92.5%,83.2%,81.5%,79.8%and 65.9%,respectively.The excellent dye degradation properties indicate that the ZnFe_(2)O_(4)-laccase has a technical application in high concentrations of dyestuff treatment.展开更多
The existence of alkali metals in fl ue gases originating from stationary sources can result in catalyst deactivation in the low-temperature selective catalytic reduction(SCR)of nitrogen oxides(NO_(x)).It is widely ac...The existence of alkali metals in fl ue gases originating from stationary sources can result in catalyst deactivation in the low-temperature selective catalytic reduction(SCR)of nitrogen oxides(NO_(x)).It is widely accepted that alkali metal poisoning causes damage to the acidic sites of catalysts.Therefore,in this study,a series of CoMn catalysts doped with heteropolyacids(HPAs)were prepared using the coprecipitation method.Among these,CoMnHPMo exhibited superior catalytic performance for SCR and over 95%NO_(x) conversion at 150-300.Moreover,it exhibited excellent catalytic activity and stability after alkali poisoning,demonstrating outstanding alkali metal resistance.The characterization indicated that HPMo increased the specifi c surface area of the catalyst,which provided abundant adsorption sites for NO_(x) and NH_(3).Comparing catalysts before and after poisoning,CoMnHPMo enhanced its alkali metal resistance by sacrifi cing Brønsted acid sites to protect its Lewis acid sites.In situ DRIFTS was used to study the reaction pathways of the catalysts.The results showed that CoMnHPMo maintained high NH_(3) adsorption capacity after K poisoning and then reacted rapidly with NO intermediates to ensure that the active sites were not covered.Consequently,SCR performance was ensured even after alkali metal poisoning.In sum-mary,this research proposed a simple method for the design of an alkali-resistant NH_(3)-SCR catalyst with high activity at low temperatures.展开更多
Lithium-sulfur(Li-S)batteries with high theoretical energy density are promising advanced energy storage devices.However,shuttling of dissolute lithium polysulfide(LiPSs)and sluggish conversion kinetics impede their a...Lithium-sulfur(Li-S)batteries with high theoretical energy density are promising advanced energy storage devices.However,shuttling of dissolute lithium polysulfide(LiPSs)and sluggish conversion kinetics impede their applications.Herein,single nickel(Ni)atoms on two-dimensional(2D)nitrogen(N)-doped carbon with Ni-N_(4)-O overcoordinated structure(SANi-N_(4)-O/NC)are prepared and firstly used as a sulfur host of Li-S batteries.Due to the efficient polysulfides traps and highly LiPSs conversion effect of SANi-N_(4)-O/NC,the electrochemical performance of Li-S batteries obviously improved.The batteries can well operate even under high sulfur loading(5.8 mg cm^(-2))and lean electrolyte(6.1μL mg^(-1))condition.Meanwhile,density functional theory(DFT)calculations demonstrate that Ni single atom’s active sites decrease the energy barriers of conversion reactions from Li_(2)S_(8)to Li2S due to the strong interaction between SANi-N_(4)-O/NC and LiPSs.Thus,the kinetic conversion of LiPSs was accelerated and the shuttle effect is suppressed on SANi-N_(4)-O/NC host.This study provides a new design strategy for a 2D structure with single-atom overcoordinated active sites to facilitate the fast kinetic conversion of LiPSs for Li-S cathode.展开更多
Spectrum prediction plays an important role for the secondary user(SU)to utilize the shared spectrum resources.However,currently utilized prediction methods are not well applied to spectrum with high burstiness,as par...Spectrum prediction plays an important role for the secondary user(SU)to utilize the shared spectrum resources.However,currently utilized prediction methods are not well applied to spectrum with high burstiness,as parameters of prediction models cannot be adjusted properly.This paper studies the prediction problem of bursty bands.Specifically,we first collect real Wi Fi transmission data in 2.4GHz Industrial,Scientific,Medical(ISM)band which is considered to have bursty characteristics.Feature analysis of the data indicates that the spectrum occupancy law of the data is time-variant,which suggests that the performance of commonly used single prediction model could be restricted.Considering that the match between diverse spectrum states and multiple prediction models may essentially improve the prediction performance,we then propose a deep-reinforcement learning based multilayer perceptron(DRL-MLP)method to address this matching problem.The state space of the method is composed of feature vectors,and each of the vectors contains multi-dimensional feature values.Meanwhile,the action space consists of several multilayer perceptrons(MLPs)that are trained on the basis of multiple classified data sets.We finally conduct experiments with the collected real data and simulations with generated data to verify the performance of the proposed method.The results demonstrate that the proposed method significantly outperforms the stateof-the-art methods in terms of the prediction accuracy.展开更多
Research of spin polarization of magnetic CoFeB thin films is of practical importance in spintronic applications.Here,using a direct characterization technique of spin-resolved photoemission spectroscopy,we obtain the...Research of spin polarization of magnetic CoFeB thin films is of practical importance in spintronic applications.Here,using a direct characterization technique of spin-resolved photoemission spectroscopy,we obtain the surface spin polarization of amorphous Co_(40)Fe_(40)B_(20)thin films with different annealing temperatures from 100℃to 500℃prepared by magnetron sputtering.After high annealing temperature,a quasi-semiconductor state is gradually formed at the CoFeB surface due to the boron diffusion.While the global magnetization remains almost constant,the secondary electrons’spin polarization,average valence band spin polarization and the spin polarization at Fermi level from spin-resolved photoemission spectroscopy show a general trend of decreasing with the increasing annealing temperature above 100℃.These distinct surface properties are attributed to the enhanced Fe-B bonding due to the boron segregation upon surface after annealing as confirmed by x-ray photoelectron spectroscopy and scanning transmission electron microscopy with energy dispersive spectroscopy.Our findings provide insight into the surface spin-resolved electronic structure of the CoFeB thin films,which should be important for development of high-performance magnetic random-access memories.展开更多
In the present study,we prepared nattokinase-loaded self-double-emulsifying drug delivery system(SDEDDS)and investigated its preliminary pharmacodynamics.The type and concentration of oil phase,inner aqueous phase and...In the present study,we prepared nattokinase-loaded self-double-emulsifying drug delivery system(SDEDDS)and investigated its preliminary pharmacodynamics.The type and concentration of oil phase,inner aqueous phase and emulsifier were screened to prepare optimum nattokinase-loaded SDEDDS.Next,the optimum formulations were characterized based on microstructure,volume-weighted mean droplet size,self-emulsifying rate,yield,storage stability,in vitro release and in vivo pharmacodynamics studies.The water/oil/watermultiple emulsions exhibited typicalmultiple structure,with relatively small volumeweighted mean droplet size 6.0±0.7μm and high self-emulsifying ability(self-emulsifying time<2 min).Encapsulation of nattokinase was up to 86.8±8.2%.The cumulative release of nattokinase within 8 h was about 30%,exhibiting a sustained release effect.The pharmacodynamics study indicated that nattokinase-loaded SDEDDS could significantly prolong the whole blood clotting time in mouse and effectively improve the carrageenan-induced tail thrombosis compared with nattokinase solution.Moreover,we showed that SDEDDS could successfully self-emulsify into water/oil/water multiple emulsions upon dilution in dispersion medium with gentle stirring and effectively protect nattokinase activity in gastric environment.Our findings suggested that SDEDDS could be a promising strategy for peptide and protein drugs by oral administration.展开更多
背景与目的自噬相关基因(autophagy related genes,ARGs)可调控溶酶体的降解过程从而诱导细胞发生自噬,参与多种癌症的发生发展,肿瘤组织中ARGs的表达情况在预测患者生存方面具有很大的前景。本研究基于ARGs构建了肺腺癌(lung adenocarc...背景与目的自噬相关基因(autophagy related genes,ARGs)可调控溶酶体的降解过程从而诱导细胞发生自噬,参与多种癌症的发生发展,肿瘤组织中ARGs的表达情况在预测患者生存方面具有很大的前景。本研究基于ARGs构建了肺腺癌(lung adenocarcinoma,LUAD)预后风险评分模型。方法通过GeneCards数据库获得5,786个ARGs。从癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库收集了395个LUAD患者的基因表达谱及临床数据,提取所有ARGs的表达数据,利用R软件筛选差异表达的ARGs。对差异表达的ARGs进行生存分析,筛选有预后价值的ARGs并进行功能富集分析。利用套索(the least absolute shrinkage and selection operator,LASSO)回归和Cox回归模型构建ARGs的预后风险评分模型。绘制受试者工作特征曲线(receiver operating characteristic curve,ROC曲线)得到风险评分的最佳cut-off值,将患者分为高风险评分组和低风险评分组。计算ROC曲线下面积(area under curve,AUC)和绘制Kaplan-Meier生存曲线评估模型性能,并在外部数据集验证。最后利用单因素和多因素Cox回归分析评价模型是否具有独立预后价值,并分析其临床相关性。结果通过生存分析初步筛选了52个与预后相关的ARGs,以此为基础,利用LASSO回归和Cox回归分析构建了由5个ARGs(ADAM12、CAMP、DKK1、STRIP2和TFAP2A)组成的LUAD预后风险评分模型。该模型中,低风险评分组患者的生存时间明显优于高风险评分组(P<0.001),且在训练集(AUCmax=0.78)和两个外部验证集(AUCmax=0.88)中均展现出良好的预测性能。风险评分在单因素和多因素Cox回归分析中与LUAD患者预后显著相关(P<0.001),提示风险评分可作为LUAD潜在的独立预后因素。临床特征相关性分析表明高风险评分与高T分期、高肿瘤分期和发生不良预后密切相关。结论我们构建了一个由5个ARGs组成的LUAD风险评分模型,该模型可为预测LUAD患者预后提供参考,未来或可与恶性肿瘤(tumor node metastasis,TNM)分期联合应用于肺腺癌患者的预后预测。展开更多
TiO2 is the most photoactive material because of its superstrong photooxidizing ability,and TiO2 photocatalysis has been widely applied in sustainable water treatment and environmental remediation.However,poor sunligh...TiO2 is the most photoactive material because of its superstrong photooxidizing ability,and TiO2 photocatalysis has been widely applied in sustainable water treatment and environmental remediation.However,poor sunlight or visible-light harvesting efficiency and fast recombination rate of the photogenerated charge carriers severely limit the practical applications of TiO2.To overcome these problems,the present work demonstrates a facile in-situ co-condensation method combined with hydrothermal treatment to prepare a series of graphitized carbon/TiO2 composite photocatalysts,and anatase TiO2 phase andp-p-conjugated polycyclic aromatic carbon structure are created simultaneously.As-prepared TiO2/C composites exhibit remarkably high visible-light photocatalytic activity in the degradation of aqueous emerging phenolic pollutants,acetaminophen(APAP)and methylparaben(MPB),and apparent rate constant of the TiO2/C composite with carbon doping level of 10.3%for APAP and MPB removal is 7.6 and 2.8 times higher than that of bare TiO2,and 6.2 and 2.6 times higher than that of Degussa P25 TiO2.Based on the results of photoelectrochemical experiments,indirect chemical probe measurements,and ESR spectroscopy,it is verified that doping TiO2 with graphitized carbon is responsible for this enhanced photocatalytic activity,which renders the improved visible-light harvesting ability,the accelerated separation of the photogenerated charge carriers,and enlarged BET surface areas.Through analyzing the intermediates yielded in the photodegradation process,the pathway of visible-light photocatalytic degradation of APAP and MPB over the TiO2/C composite is proposed.展开更多
Background:Gastrointestinal(GI)injury is one of the most common side effects of radiotherapy.However,there is no ideal therapy method except for symptomatic treatment in the clinic.Xuebijing(XBJ)is a traditional Chine...Background:Gastrointestinal(GI)injury is one of the most common side effects of radiotherapy.However,there is no ideal therapy method except for symptomatic treatment in the clinic.Xuebijing(XBJ)is a traditional Chinese medicine,used to treat sepsis by injection.In this study,the protective effects of XBJ on radiation-i nduced intestinal injury(RⅢ)and its mechanism were explored.Methods:The effect of XBJ on survival of irradiated C57BL/6 mice was monitored.Histological changes including the number of crypts and the length of villi were evaluated by H&E.The expression of Lgr5^(+)intestinal stem cells(ISCs),Ki67^(+)cells,villin and lysozymes were examined by immunohistochemistry.The expression of cytokines in the intestinal crypt was detected by RT-PCR.DNA damage and apoptosis rates in the small intestine were also evaluated by immunofluorescence.Results:In the present study,XBJ improved the survival rate of the mice after 8.0and 9.0 Gy total body irradiation(TBI).XBJ attenuated structural damage of the small intestine,maintained regenerative ability and promoted proliferation and differentiation of crypt cells,decreased apoptosis rate and reduced DNA damage in the intestine.Elevation of IL-6 and TNF-α was limited,but IL-1,TNF-β and IL-10 levels were increased in XBJ-treated group after irradiation.The expression of Bax and p53 were decreased after XBJ treatment.Conclusions:Taken together,XBJ provides a protective effect on RⅢby inhibiting inflammation and blocking p53-related apoptosis pathway.展开更多
Objective:In the phase II ALTER-1202(NCT03059797)trial,anlotinib significantly improved progression-free survival(PFS)and overall survival(OS)in patients with advanced small-cell lung cancer(SCLC)who underwent at leas...Objective:In the phase II ALTER-1202(NCT03059797)trial,anlotinib significantly improved progression-free survival(PFS)and overall survival(OS)in patients with advanced small-cell lung cancer(SCLC)who underwent at least 2 previous chemotherapy cycles,when compared with a placebo group.To identify potential factors for predicting efficacy and prognosis with anlotinib treatment,we analyzed hematological indices at baseline and adverse events(AEs)over the course of anlotinib treatment.Methods:Data were collected from March 2017 to April 2019 from a randomized,double-blind,placebo-controlled,multicenter,phase II trial of anlotinib.Eligible patients were randomly assigned 2:1 to receive anlotinib or placebo until disease progression,intolerable toxicity,or withdrawal of consent.The patients received anlotinib(12 mg)or an analogue capsule(placebo)orally once daily for 14 days every 3 weeks.The hematological indices at baseline and AEs that occurred in the initial 2 treatment cycles were recorded.The Kaplan-Meier test and Cox regression model were used to assess survival differences.Results:A total of 82 patients(81 patients with complete data)were randomly assigned to receive anlotinib,with 38 receiving a placebo as a control.Multivariate analysis indicated that an elevated neutrophil to lymphocyte ratio>7.75 and lactate dehydrogenase>254.65 U/L at baseline were independent risk factors for PFS;basal elevated aspartate aminotransferase>26.75 U/L,neuron specific enolase>18.64 ng/mL,and fibrinogen>4.645 g/L were independent risk factors for OS.During treatment,elevatedγglutamyltransferase and hypophosphatemia were independent predictors for a poor PFS,and elevatedγ-glutamyl transferase and hypercholesterolemia were independent factors for OS.Conclusions:Our study preliminarily defined potential factors that affected the PFS and OS at baseline and during anlotinib treatment in patients with advanced SCLC.Our findings provide a basis for screening the dominant population and for dynamic efficacy monitoring with anlotinib therapy.展开更多
基金supported by the National Natural Science Foundation of China, No.82274616the Key Laboratory Project for General Universities in Guangdong Province, No.2019KSYS005Guangdong Province Science and Technology Plan International Cooperation Project, No.2020A0505100052 (all to QW)。
文摘Meningeal lymphatic vessels form a relationship between the nervous system and periphery, which is relevant in both health and disease. Meningeal lymphatic vessels not only play a key role in the drainage of brain metabolites but also contribute to antigen delivery and immune cell activation. The advent of novel genomic technologies has enabled rapid progress in the characterization of myeloid and lymphoid cells and their interactions with meningeal lymphatic vessels within the central nervous system. In this review, we provide an overview of the multifaceted roles of meningeal lymphatic vessels within the context of the central nervous system immune network, highlighting recent discoveries on the immunological niche provided by meningeal lymphatic vessels. Furthermore, we delve into the mechanisms of crosstalk between meningeal lymphatic vessels and immune cells in the central nervous system under both homeostatic conditions and neurodegenerative diseases, discussing how these interactions shape the pathological outcomes. Regulation of meningeal lymphatic vessel function and structure can influence lymphatic drainage, cerebrospinal fluid-borne immune modulators, and immune cell populations in aging and neurodegenerative disorders, thereby playing a key role in shaping meningeal and brain parenchyma immunity.
基金supported by the National Natural Science Foundation of China (no. 31960048 and 31872649)Yunnan Revitalization Talent Support Program (no. YNWRQNBJ-2019-208)+2 种基金the Department of Science and Technology of Yunnan Province (no. 202201AT070118)the Hundred Talents Program of Kunming Medical University (no. 60118260127)the Gaoligong Mountain, Forest Ecosystem, Observation and Research Station of Yunnan Province (no. 202205AM070006)。
文摘The East Asia(or Physospermopsis) clade was recognized in previous molecular phylogenetic investigations into the higher-level relationships of Apiaceae subfamily Apioideae. The composition of this clade, the phylogenetic relationships among its constituent taxa, and the placement of species previously determined to be problematic have yet to be resolved. Herein, nr DNA ITS sequences were obtained for150 accessions of Apioideae, representing species whose distributions are in East Asia or genera having one or more species included within the East Asia clade. These data, along with published ITS sequences from other Apioideae(for 3678 accessions altogether), were subjected to maximum likelihood and Bayesian inference analyses. The results show that the East Asia clade contains representatives of 11currently recognized genera: Hansenia, Hymenolaena, Keraymonia, Sinolimprichtia, Acronema, Hymenidium, Physospermopsis, Pimpinella, Sinocarum, Tongoloa, and Trachydium. However, the latter seven genera have members falling outside of the East Asia clade, including the generic types of all except Tongoloa. Within the clade, the species comprising these seven genera are widely intermingled, greatly increasing confusion among relationships than previously realized. The problematic species Physospermopsis cuneata is confirmed as falling within the East Asia clade, whereas P. rubrinervis allies with the generic type in tribe Pleurospermeae. Physospermopsis kingdon-wardii is confirmed as a member of the genus Physospermopsis, whereas the generic attributions of P. cuneata and Tongoloa stewardii remain unclear. Two species of Sinocarum(S. filicinum and S. wolffianum) are transferred into the genus Meeboldia. This is the most comprehensive molecular phylogenetic investigation of the East Asia clade to date, and while the results increase systematic understanding of the clade, they also highlight the need for further studies of one of the most taxonomically intractable groups in Apioideae.
基金supported by the National Natural Science Foundation of China(21471002)Scientific Research Projects of Universities in Anhui Province(2022AH040135)+1 种基金Natural Science Research Project for Anhui Universities(KJ2021A0509)Anhui Natural Science Foundation(2208085MC83).
文摘Efficient and convenient treatment of industrial dyeing wastewater is of great significance to guarantee human and animal health.This work presented the enhanced catalytic activity at pH 3.0 of laccase immobilized on amino-functionalized ZnFe_(2)O_(4) nanoparticles(ZnFe_(2)O_(4)-laccase)and its application for the degradation of textile dyes.Due to the existence of a large number of oxygen vacancies on the surface of the ZnFe_(2)O_(4) nanoparticles,negative ions accumulated on the magnetic carriers,which resulted in a harsh optimal pH value of the ZnFe_(2)O_(4)-laccase.Laccase activity assays revealed that the ZnFe_(2)O_(4)-laccase possessed superior pH and thermal stabilities,excellent reusability,and noticeable organic solvent tolerance.Meanwhile,the ZnFe_(2)O_(4) laccase presented efficient and sustainable degradation of high concentrations of textile dyes.The initial decoloration efficiencies of malachite green(MG),brilliant green(BG),azophloxine,crystal violet(CV),reactive blue 19(RB19),and procion red MX-5B were approximately 99.1%,95.0%,93.3%,87.4%,86.1%,and 85.3%,respectively.After 10 consecutive reuses,the degradation rates of the textile dyes still maintained about 98.2%,92.5%,83.2%,81.5%,79.8%and 65.9%,respectively.The excellent dye degradation properties indicate that the ZnFe_(2)O_(4)-laccase has a technical application in high concentrations of dyestuff treatment.
基金This work was supported by the National Key R&D Program of China(Nos.2022YFB3504100 and 2022YFB3504102)Natural National Science Foundation of China(No.22276133)+1 种基金Natural National Science Foundation of China(No.U20A20132)Natural National Science Foundation of China(No.52106180).
文摘The existence of alkali metals in fl ue gases originating from stationary sources can result in catalyst deactivation in the low-temperature selective catalytic reduction(SCR)of nitrogen oxides(NO_(x)).It is widely accepted that alkali metal poisoning causes damage to the acidic sites of catalysts.Therefore,in this study,a series of CoMn catalysts doped with heteropolyacids(HPAs)were prepared using the coprecipitation method.Among these,CoMnHPMo exhibited superior catalytic performance for SCR and over 95%NO_(x) conversion at 150-300.Moreover,it exhibited excellent catalytic activity and stability after alkali poisoning,demonstrating outstanding alkali metal resistance.The characterization indicated that HPMo increased the specifi c surface area of the catalyst,which provided abundant adsorption sites for NO_(x) and NH_(3).Comparing catalysts before and after poisoning,CoMnHPMo enhanced its alkali metal resistance by sacrifi cing Brønsted acid sites to protect its Lewis acid sites.In situ DRIFTS was used to study the reaction pathways of the catalysts.The results showed that CoMnHPMo maintained high NH_(3) adsorption capacity after K poisoning and then reacted rapidly with NO intermediates to ensure that the active sites were not covered.Consequently,SCR performance was ensured even after alkali metal poisoning.In sum-mary,this research proposed a simple method for the design of an alkali-resistant NH_(3)-SCR catalyst with high activity at low temperatures.
基金financial support from the National Natural Science Foundation of China(21878270,21878267,21922811,21978258 and 21961160742)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(2019R01006)+3 种基金the Zhejiang Provincial Natural Science Foundation of China(LR19B060002)the Fundamental Research Funds for the Central Universities(2020XZZX002-09)the Startup Foundation for Hundred-Talent Program of Zhejiang Universitythe Zhejiang Key Laboratory of Marine Materials and Protective Technologies(2020K10)。
文摘Lithium-sulfur(Li-S)batteries with high theoretical energy density are promising advanced energy storage devices.However,shuttling of dissolute lithium polysulfide(LiPSs)and sluggish conversion kinetics impede their applications.Herein,single nickel(Ni)atoms on two-dimensional(2D)nitrogen(N)-doped carbon with Ni-N_(4)-O overcoordinated structure(SANi-N_(4)-O/NC)are prepared and firstly used as a sulfur host of Li-S batteries.Due to the efficient polysulfides traps and highly LiPSs conversion effect of SANi-N_(4)-O/NC,the electrochemical performance of Li-S batteries obviously improved.The batteries can well operate even under high sulfur loading(5.8 mg cm^(-2))and lean electrolyte(6.1μL mg^(-1))condition.Meanwhile,density functional theory(DFT)calculations demonstrate that Ni single atom’s active sites decrease the energy barriers of conversion reactions from Li_(2)S_(8)to Li2S due to the strong interaction between SANi-N_(4)-O/NC and LiPSs.Thus,the kinetic conversion of LiPSs was accelerated and the shuttle effect is suppressed on SANi-N_(4)-O/NC host.This study provides a new design strategy for a 2D structure with single-atom overcoordinated active sites to facilitate the fast kinetic conversion of LiPSs for Li-S cathode.
基金supported in part by the China National Key R&D Program(no.2020YF-B1808000)Beijing Natural Science Foundation(No.L192002)+2 种基金in part by the Fundamental Research Funds for the Central Universities(No.328202206)the National Natural Science Foundation of China(No.61971058)in part by"Advanced and sophisticated"discipline construction project of universities in Beijing(No.20210013Z0401)。
文摘Spectrum prediction plays an important role for the secondary user(SU)to utilize the shared spectrum resources.However,currently utilized prediction methods are not well applied to spectrum with high burstiness,as parameters of prediction models cannot be adjusted properly.This paper studies the prediction problem of bursty bands.Specifically,we first collect real Wi Fi transmission data in 2.4GHz Industrial,Scientific,Medical(ISM)band which is considered to have bursty characteristics.Feature analysis of the data indicates that the spectrum occupancy law of the data is time-variant,which suggests that the performance of commonly used single prediction model could be restricted.Considering that the match between diverse spectrum states and multiple prediction models may essentially improve the prediction performance,we then propose a deep-reinforcement learning based multilayer perceptron(DRL-MLP)method to address this matching problem.The state space of the method is composed of feature vectors,and each of the vectors contains multi-dimensional feature values.Meanwhile,the action space consists of several multilayer perceptrons(MLPs)that are trained on the basis of multiple classified data sets.We finally conduct experiments with the collected real data and simulations with generated data to verify the performance of the proposed method.The results demonstrate that the proposed method significantly outperforms the stateof-the-art methods in terms of the prediction accuracy.
基金supported by the National Key Research and Development Program of China(Grant No.2021YFB3601600)the National Natural Science Foundation of China(Grant Nos.12104216,61427812,11774160,51971109,51871236,51771053,U1806219)+1 种基金the Natural Science Foundation of Jiangsu Province of China(Grant Nos.BK20200307,BK20192006,BK20180056)the Fundamental Research Funds for the Central Universities(Grant No.21014380113)。
文摘Research of spin polarization of magnetic CoFeB thin films is of practical importance in spintronic applications.Here,using a direct characterization technique of spin-resolved photoemission spectroscopy,we obtain the surface spin polarization of amorphous Co_(40)Fe_(40)B_(20)thin films with different annealing temperatures from 100℃to 500℃prepared by magnetron sputtering.After high annealing temperature,a quasi-semiconductor state is gradually formed at the CoFeB surface due to the boron diffusion.While the global magnetization remains almost constant,the secondary electrons’spin polarization,average valence band spin polarization and the spin polarization at Fermi level from spin-resolved photoemission spectroscopy show a general trend of decreasing with the increasing annealing temperature above 100℃.These distinct surface properties are attributed to the enhanced Fe-B bonding due to the boron segregation upon surface after annealing as confirmed by x-ray photoelectron spectroscopy and scanning transmission electron microscopy with energy dispersive spectroscopy.Our findings provide insight into the surface spin-resolved electronic structure of the CoFeB thin films,which should be important for development of high-performance magnetic random-access memories.
基金supported by National Natural Science Foundation of China(No.81373338).
文摘In the present study,we prepared nattokinase-loaded self-double-emulsifying drug delivery system(SDEDDS)and investigated its preliminary pharmacodynamics.The type and concentration of oil phase,inner aqueous phase and emulsifier were screened to prepare optimum nattokinase-loaded SDEDDS.Next,the optimum formulations were characterized based on microstructure,volume-weighted mean droplet size,self-emulsifying rate,yield,storage stability,in vitro release and in vivo pharmacodynamics studies.The water/oil/watermultiple emulsions exhibited typicalmultiple structure,with relatively small volumeweighted mean droplet size 6.0±0.7μm and high self-emulsifying ability(self-emulsifying time<2 min).Encapsulation of nattokinase was up to 86.8±8.2%.The cumulative release of nattokinase within 8 h was about 30%,exhibiting a sustained release effect.The pharmacodynamics study indicated that nattokinase-loaded SDEDDS could significantly prolong the whole blood clotting time in mouse and effectively improve the carrageenan-induced tail thrombosis compared with nattokinase solution.Moreover,we showed that SDEDDS could successfully self-emulsify into water/oil/water multiple emulsions upon dilution in dispersion medium with gentle stirring and effectively protect nattokinase activity in gastric environment.Our findings suggested that SDEDDS could be a promising strategy for peptide and protein drugs by oral administration.
文摘背景与目的自噬相关基因(autophagy related genes,ARGs)可调控溶酶体的降解过程从而诱导细胞发生自噬,参与多种癌症的发生发展,肿瘤组织中ARGs的表达情况在预测患者生存方面具有很大的前景。本研究基于ARGs构建了肺腺癌(lung adenocarcinoma,LUAD)预后风险评分模型。方法通过GeneCards数据库获得5,786个ARGs。从癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库收集了395个LUAD患者的基因表达谱及临床数据,提取所有ARGs的表达数据,利用R软件筛选差异表达的ARGs。对差异表达的ARGs进行生存分析,筛选有预后价值的ARGs并进行功能富集分析。利用套索(the least absolute shrinkage and selection operator,LASSO)回归和Cox回归模型构建ARGs的预后风险评分模型。绘制受试者工作特征曲线(receiver operating characteristic curve,ROC曲线)得到风险评分的最佳cut-off值,将患者分为高风险评分组和低风险评分组。计算ROC曲线下面积(area under curve,AUC)和绘制Kaplan-Meier生存曲线评估模型性能,并在外部数据集验证。最后利用单因素和多因素Cox回归分析评价模型是否具有独立预后价值,并分析其临床相关性。结果通过生存分析初步筛选了52个与预后相关的ARGs,以此为基础,利用LASSO回归和Cox回归分析构建了由5个ARGs(ADAM12、CAMP、DKK1、STRIP2和TFAP2A)组成的LUAD预后风险评分模型。该模型中,低风险评分组患者的生存时间明显优于高风险评分组(P<0.001),且在训练集(AUCmax=0.78)和两个外部验证集(AUCmax=0.88)中均展现出良好的预测性能。风险评分在单因素和多因素Cox回归分析中与LUAD患者预后显著相关(P<0.001),提示风险评分可作为LUAD潜在的独立预后因素。临床特征相关性分析表明高风险评分与高T分期、高肿瘤分期和发生不良预后密切相关。结论我们构建了一个由5个ARGs组成的LUAD风险评分模型,该模型可为预测LUAD患者预后提供参考,未来或可与恶性肿瘤(tumor node metastasis,TNM)分期联合应用于肺腺癌患者的预后预测。
文摘TiO2 is the most photoactive material because of its superstrong photooxidizing ability,and TiO2 photocatalysis has been widely applied in sustainable water treatment and environmental remediation.However,poor sunlight or visible-light harvesting efficiency and fast recombination rate of the photogenerated charge carriers severely limit the practical applications of TiO2.To overcome these problems,the present work demonstrates a facile in-situ co-condensation method combined with hydrothermal treatment to prepare a series of graphitized carbon/TiO2 composite photocatalysts,and anatase TiO2 phase andp-p-conjugated polycyclic aromatic carbon structure are created simultaneously.As-prepared TiO2/C composites exhibit remarkably high visible-light photocatalytic activity in the degradation of aqueous emerging phenolic pollutants,acetaminophen(APAP)and methylparaben(MPB),and apparent rate constant of the TiO2/C composite with carbon doping level of 10.3%for APAP and MPB removal is 7.6 and 2.8 times higher than that of bare TiO2,and 6.2 and 2.6 times higher than that of Degussa P25 TiO2.Based on the results of photoelectrochemical experiments,indirect chemical probe measurements,and ESR spectroscopy,it is verified that doping TiO2 with graphitized carbon is responsible for this enhanced photocatalytic activity,which renders the improved visible-light harvesting ability,the accelerated separation of the photogenerated charge carriers,and enlarged BET surface areas.Through analyzing the intermediates yielded in the photodegradation process,the pathway of visible-light photocatalytic degradation of APAP and MPB over the TiO2/C composite is proposed.
基金CAMS Medicine and Health Technology Innovation ProjectGrant/Award Number:2021-I2M-1-060 and 2021-RC310-010+1 种基金National Natural Science Foundation of ChinaGrant/Award Number:81972975。
文摘Background:Gastrointestinal(GI)injury is one of the most common side effects of radiotherapy.However,there is no ideal therapy method except for symptomatic treatment in the clinic.Xuebijing(XBJ)is a traditional Chinese medicine,used to treat sepsis by injection.In this study,the protective effects of XBJ on radiation-i nduced intestinal injury(RⅢ)and its mechanism were explored.Methods:The effect of XBJ on survival of irradiated C57BL/6 mice was monitored.Histological changes including the number of crypts and the length of villi were evaluated by H&E.The expression of Lgr5^(+)intestinal stem cells(ISCs),Ki67^(+)cells,villin and lysozymes were examined by immunohistochemistry.The expression of cytokines in the intestinal crypt was detected by RT-PCR.DNA damage and apoptosis rates in the small intestine were also evaluated by immunofluorescence.Results:In the present study,XBJ improved the survival rate of the mice after 8.0and 9.0 Gy total body irradiation(TBI).XBJ attenuated structural damage of the small intestine,maintained regenerative ability and promoted proliferation and differentiation of crypt cells,decreased apoptosis rate and reduced DNA damage in the intestine.Elevation of IL-6 and TNF-α was limited,but IL-1,TNF-β and IL-10 levels were increased in XBJ-treated group after irradiation.The expression of Bax and p53 were decreased after XBJ treatment.Conclusions:Taken together,XBJ provides a protective effect on RⅢby inhibiting inflammation and blocking p53-related apoptosis pathway.
文摘Objective:In the phase II ALTER-1202(NCT03059797)trial,anlotinib significantly improved progression-free survival(PFS)and overall survival(OS)in patients with advanced small-cell lung cancer(SCLC)who underwent at least 2 previous chemotherapy cycles,when compared with a placebo group.To identify potential factors for predicting efficacy and prognosis with anlotinib treatment,we analyzed hematological indices at baseline and adverse events(AEs)over the course of anlotinib treatment.Methods:Data were collected from March 2017 to April 2019 from a randomized,double-blind,placebo-controlled,multicenter,phase II trial of anlotinib.Eligible patients were randomly assigned 2:1 to receive anlotinib or placebo until disease progression,intolerable toxicity,or withdrawal of consent.The patients received anlotinib(12 mg)or an analogue capsule(placebo)orally once daily for 14 days every 3 weeks.The hematological indices at baseline and AEs that occurred in the initial 2 treatment cycles were recorded.The Kaplan-Meier test and Cox regression model were used to assess survival differences.Results:A total of 82 patients(81 patients with complete data)were randomly assigned to receive anlotinib,with 38 receiving a placebo as a control.Multivariate analysis indicated that an elevated neutrophil to lymphocyte ratio>7.75 and lactate dehydrogenase>254.65 U/L at baseline were independent risk factors for PFS;basal elevated aspartate aminotransferase>26.75 U/L,neuron specific enolase>18.64 ng/mL,and fibrinogen>4.645 g/L were independent risk factors for OS.During treatment,elevatedγglutamyltransferase and hypophosphatemia were independent predictors for a poor PFS,and elevatedγ-glutamyl transferase and hypercholesterolemia were independent factors for OS.Conclusions:Our study preliminarily defined potential factors that affected the PFS and OS at baseline and during anlotinib treatment in patients with advanced SCLC.Our findings provide a basis for screening the dominant population and for dynamic efficacy monitoring with anlotinib therapy.
