Background:In the Chinese context,the impact of short video applications on the psychological well-being of older adults is contested.While often examined through a pathological lens of addiction,this perspective may ...Background:In the Chinese context,the impact of short video applications on the psychological well-being of older adults is contested.While often examined through a pathological lens of addiction,this perspective may overlook paradoxical,context-dependent positive outcomes.Therefore,the main objective of this study is to challenge the traditional Compensatory Internet Use Theory by proposing and testing a chained mediation model that explores a paradoxical pathway from social support to life satisfaction via problematic social media use.Methods:Data were collected between July and August 2025 via the Credamo online survey platform,yielding 384 valid responses from Chinese older adults aged 60 and above.Key constructs were assessed using the Social Support Rating Scale(SSRS),Bergen Social Media Addiction Scale(BSMAS),Simplified UCLA Loneliness Scale,and Satisfaction with Life Scale(SWLS).A chained mediation model was tested using stepwise regression and non-parametric bootstrapping(5000 resamples),controlling for age,gender,household income,and health status.Results:The analysis revealed a paradoxical pathway,which was clarified by a key statistical suppression effect.Social support significantly and positively predicted problematic usage(β=0.157,p=0.002).After controlling for the suppressor effect of social support,problematic usage in turn negatively predicted social connectedness(β=−0.177,p<0.001).Finally,reduced social connectedness—reflecting a state of solitude—positively predicted life satisfaction(β=−0.227,p<0.001).Conclusion:The findings suggest that for older adults with sufficient offline social support,these resources may serve a“social empowerment”function.This empowerment allows behaviors measured as“problematic usage”to be theoretically reframed as a form of“deep immersive entertainment”.This immersion appears to occur alongside a state of“high-quality solitude”,which ultimately is associated with higher life satisfaction.This study provides a novel,non-pathological theoretical perspective on the consequences of high engagement with emerging social media,offering empirical grounds for non-abstinence-based intervention strategies.展开更多
Crimean-Congo hemorrhagic fever virus(CCHFV)is a highly pathogenic tick-borne virus that causes severe hemorrhagic fever with high mortality rates in humans.No licensed vaccines or efficacious antiviral therapies are ...Crimean-Congo hemorrhagic fever virus(CCHFV)is a highly pathogenic tick-borne virus that causes severe hemorrhagic fever with high mortality rates in humans.No licensed vaccines or efficacious antiviral therapies are currently available.Here,we identified seven heavy chain antibodies targeting CCHFV Gc,which consist of heavy-chain variable domain(VHH)fused to human IgG1 Fc region(VHHFc).These VHH-Fc antibodies exhibited neutralizing activity against both recombinant vesicular stomatitis virus(VSV)-vectored CCHFV pseudoviruses and CCHFV transcriptionand entry-competent virus-like particles(tecVLPs).Among these,N025 achieved the most potent pseudovirus neutralization,while N013 showed remarkable efficacy in tecVLP systems,with IC_(50) values of 22.7 ng/mL and 33.0 ng/mL,respectively.AlphaFold3 structural predictions revealed that all characterized VHH-Fc antibodies target epitopes within Domain Ⅱ of the Gc protein,with partial or complete overlap with the fusion loop region.Alanine scanning mutagenesis confirmed the functional significance of these epitopes,with N013 showing the highest binding energy change(ΔΔG=25.36 kcal/mol)and moderate competition with a known fusion loop-targeting antibody.Sequence conservation analysis across representative CCHFV strains from different genetic lineages demonstrated complete conservation of the N013 and N025 epitopes,suggesting potential for broad-spectrum neutralizing activity.Together,our findings provide a novel strategy for developing CCHFV therapeutics and identify promising antibody candidates that could inform future broad-spectrum antiviral development efforts.展开更多
Spinal cord stimulation （SCS） is a promising technique for treating disorders of consciousness （DOCs）. However, differences in the spatio-temporal responsiveness of the brain under varied SCS parameters remain unc...Spinal cord stimulation （SCS） is a promising technique for treating disorders of consciousness （DOCs）. However, differences in the spatio-temporal responsiveness of the brain under varied SCS parameters remain unclear. In this pilot study, functional near-infrared spectroscopy was used to measure the hemodynamic responses of 10 DOC patients to different SCS frequencies （5 Hz, 10 Hz, 50 Hz, 70 Hz, and 100 Hz）. In the prefrontal cortex, a key area in consciousness circuits, we found significantly increased hemodynamic responses at 70 Hz and 100 Hz, and significantly different hemodynamic responses between 50 Hz and 70 Hz/100 Hz. In addition, the functional connectivity between prefrontal and occipital areas was significantly improved with SCS at 70 Hz. These results demonstrated that SCS modulates the hemodynamic responses and long-range connectivity in a frequency-specific manner （with 70 Hz apparently better）, perhaps by improving the cerebral blood volume and information transmission through the reticular formation-thalamus-cortex pathway.展开更多
A metabonomic approach involving an ultrahigh-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry(UHPLC-FT-ICR-MS)was used to investigate the changes in the endo...A metabonomic approach involving an ultrahigh-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry(UHPLC-FT-ICR-MS)was used to investigate the changes in the endogenous metabolites in the plasma of rats with yeast-induced pyrexia treated with Gegenqinlian decoction(GQLD),aspirin and itraconazole.The differences in the small molecule profiles of treatment using traditional Chinese medicine,etiological treatment and symptomatic treatment were elucidated.Thirty-six plasma metabolites were identified or putatively identified,and the effects of the three medicines on the thirty-six metabolites were studied.Their metabolic pathways indicated that GQLD,aspirin and itraconazole ameliorated the rats with yeast-induced pyrexia predominantly by regulating the metabolisms of phospholipid,sphingolipid,fatty acid oxidation,fatty acid amides,amino acid and glycerolipid in vivo.The pharmacodynamics and metabonomic results showed that the three medicines exhibited the therapeutic effects on pyrexia by regulating the perturbations of multiple metabolisms.The study provided a scientific basis for an in-depth understanding of the therapeutic effects of GQLD,aspirin and itraconazole on rats with yeast-induced pyrexia.展开更多
Neuroimaging has opened new opportunities to study the neural correlates of consciousness, and provided additional information concerning diagnosis, prognosis, and therapeutic interventions in patients with disorders ...Neuroimaging has opened new opportunities to study the neural correlates of consciousness, and provided additional information concerning diagnosis, prognosis, and therapeutic interventions in patients with disorders of consciousness. Here, we aim to review neuroimaging studies in chronic disorders of consciousness from the viewpoint of the brain network, focusing on positron emission tomogra- phy, functional MRI, functional near-infrared spectroscopy, electrophysiology, and diffusion MRI. To accelerate basic research on disorders of consciousness and provide a panoramic view of unconsciousness, we propose that it is urgent to integrate different techniques at various spatiotemporal scales, and to merge fragmented findings into a uniform ＂Brainnetome＂ （Brain-net-ome） research framework.展开更多
This article investigates the performances of different extractive distillation processes intensified with dividing-wall column for separating benzene-isopropanol-water ternary mixtures.All the processes with ethylene...This article investigates the performances of different extractive distillation processes intensified with dividing-wall column for separating benzene-isopropanol-water ternary mixtures.All the processes with ethylene glycol as solvent are optimized with the minimal total annual cost(TAC)as target.In order to get the global optimal solution intelligently,an improved simulated annealing algorithm is adopted,which is programmed in MATLAB and linked to Aspen Plus.The results show that the extractive dividing wall column-solvent(EDWC-S)process consisting of an extractive dividing wall column and a solvent recovery column is the best scheme.It can reduce the TAC by 28.65%and CO_(2) emissions by 32.84% compared to the conventional triple-column extractive distillation process.展开更多
The present investigation reports the chemical composition of the Rhus typhina L.stem identified via mass spectrometry and NMR as gallic acid,1-O-galloyl-β-D-glucose,tryptophan,scopolin,methyl gallate,fustin,querceti...The present investigation reports the chemical composition of the Rhus typhina L.stem identified via mass spectrometry and NMR as gallic acid,1-O-galloyl-β-D-glucose,tryptophan,scopolin,methyl gallate,fustin,quercetin,rutin,and 1,2,3,4,6-penta-O-galloyl-β-D-glucose.The antioxidant properties and the chemical composition contents of the R.typhina L.stem grown in different regions in China were determined.To determine the antioxidant activity,a total phenolic content analysis,2,2-diphenyl-1-picrylhydrazyl radical scavenging activity assay,ferric reducing antioxidant power assay,andβ-carotene linoleic acid model system were conducted.The results showed that the Rhus typhina L.stem possessed high antioxidant capacities due to its high phenolic content.The contents of the nine isolated compounds were determined by UPLC-ESI-MS/MS.The calibration curves of the nine isolated compounds were linear within the concentration range and the average recoveries were high.The result showed that 1-Ogalloyl-β-D-glucose,gallic acid,methyl gallate,and 1,2,3,4,6-penta-O-galloyl-β-D-glucose could be the compounds mainly responsible for the antioxidant capacity of the R.typhina L.stem.This reveals that the R.typhina L.stem is a good source of antioxidants.展开更多
Objective To screen the target genes that are associated with survival of breast cancer(BRCA) and explore their prognostic values and immune correlations with BRCA using multiple databases..Methods The microarray expr...Objective To screen the target genes that are associated with survival of breast cancer(BRCA) and explore their prognostic values and immune correlations with BRCA using multiple databases..Methods The microarray expression datasets of BRCA were downloaded from the Gene Expresssion Omnibus database(GEO) and analyzed to obtain differentially expressed genes(DEGs). Hub genes were obtained by constructing and visualizing the protein-protein interaction network of DEGs. The key gene was determined using R language, STRING, and Cytoscape, and the differential expression of the key gene was verified using external datasets The Cancer Genome Atlas(TCGA) and quantitative real-time PCR(q RT-PCR) for BRCA tissues of 37 patients. The prognostic value and immunological correlation of UBE2C in BRCA were explored using R language, TIMER, and Gene Set Enrichment Analysis(GSEA).Results Of 10 hub genes seleceed from 302 DEGS, UBE2C was identified as the gene associated with BRCA survival. The expression of UBE2C was differentially upregulated in BRCA, as verified by TCGA and q RT-PCR. Prognostic analysis revealed that UBE2C served as an independent prognostic factor. High expression of UBE2C was associated with decreased immune infiltration levels of B cells, CD4+ T cells, CD8+ T cells, macrophages, and myeloid dendritic cells in BRCA tissue. The expression of UBE2C in BRCA showed a significant correlation with immune checkpoints genes PDCD1, CD274, and CTLA4 expressions. There was a positive correlation between the expression of UBE2C and the tumor mutational burden and microsatellite instability. GSEA demonstrated that UBE2C expression significantly enriched 786 immune-related gene sets.Conclusions UBE2C expression in BRCA tissues is closely related to the BRCA immune microenvironment and showes predictive values on the survivals and prognosis of BRCA patients and the effecacy of immunotherapy. UBE2C may be an potential immune-related prognostic biomarker for BRCA.展开更多
We have theoretically and experimentally studied the dispersive signal of the Rydberg atomic electromagneticallyinduced transparency(EIT)Autler–Townes(AT)splitting spectra obtained using amplitude modulation of the m...We have theoretically and experimentally studied the dispersive signal of the Rydberg atomic electromagneticallyinduced transparency(EIT)Autler–Townes(AT)splitting spectra obtained using amplitude modulation of the microwave(MW)electric field.In addition to the two zero-crossing points interval△f_(zeros),the dispersion signal has two positive maxima with an interval defined as the shoulder interval△f_(sho),which is theoretically expected to be used to measure a much weaker MW electric field.The relationship of the MW field strength E_(MW)and△f_(sho)is experimentally studied at the MW frequencies of 31.6 GHz and 9.2 GHz respectively.The results show that△f_(sho)can be used to characterize the much weaker E_(MW)than that of△f_(zeros)and the traditional EIT–AT splitting interval△f_(m);the minimum E_(MW)measured by△f_(sho)is about 30 times smaller than that by△f_(m).As an example,the minimum E_(MW)at 9.2 GHz that can be characterized by△f_(sho)is 0.056 mV/cm,which is the minimum value characterized by the frequency interval using a vapor cell without adding any auxiliary fields.The proposed method can improve the weak limit and sensitivity of E_(MW)measured by the spectral frequency interval,which is important in the direct measurement of weak E_(MW).展开更多
This study aims to improve the performances of the high-pressure water descaling technology used in steel hot rolling processes.In particular,a 2050 mm hot rolling line is considered,and the problem is investigated by...This study aims to improve the performances of the high-pressure water descaling technology used in steel hot rolling processes.In particular,a 2050 mm hot rolling line is considered,and the problem is investigated by means of a fluid–structure interaction(FSI)method by which the descaling effect produced by rolling coils with different section sizes is examined.Assuming a flat fan-shaped nozzle at the entrance of the R1R2 roughing mill,the outflow field characteristics and the velocity distribution curve on the strike line(at a target distance of 30–120 mm)are determined.It is found that the velocity in the center region of the water jet with different target distances is higher than that in the boundary region.As the target distance increases,the velocity of the water jet in the central region decreases.Through comparison with experimental results,it is shown that the simulation model can accurately predict the impact position of the high-pressure water on the impact plate,thereby providing a computational scheme that can be used to optimize the nozzle space layout and improve the slabs’descent effect for different rolling specifications.展开更多
Gases containing sulfur oxides can cause corrosion and failure of bellows used as furnace blowers in high-temperature environments.In order to mitigate this issue,the behavior of an effective blast furnace blower has ...Gases containing sulfur oxides can cause corrosion and failure of bellows used as furnace blowers in high-temperature environments.In order to mitigate this issue,the behavior of an effective blast furnace blower has been examined in detail.Firstly,the Sereda corrosion model has been introduced to simulate the corrosion rate of the related bellows taking into account the effects of temperature and SO_(2) gas;such results have been compared with effective measurements;then,the average gas velocity in the pipeline and the von Mises stress distribution of the inner draft tube have been analyzed using a Fluid-Structure Interaction model.Finally,the semi-closed internal corrosion environment caused by a 5 mm radial gap between the inner draft tube and the bellows has been considered.The gas flow rate in the residential space has been found to be low(0.5 ms–this value leads to a stable semi-closed internal corrosion environment for exhaust gas exchange);water phase in the exhaust gas is prone to accelerate the corrosion rate.On this basis,a bellows with an optimized inner draft tube has proposed,which includes corrosion-resistant honeycomb buffer rings.展开更多
In order to analyze the microscopic theory of viscous-elastic fluid flooding residual oil, the flow equation of polymer solution in the micro pore can be derived by selecting upper-convected Maxwell constitutive equat...In order to analyze the microscopic theory of viscous-elastic fluid flooding residual oil, the flow equation of polymer solution in the micro pore can be derived by selecting upper-convected Maxwell constitutive equation, continuity equation and motion equation. Then, the flow velocity field and stress field can be calculated under the boundary condition, and with the theory of stress tensor, the horizontal stress difference of polymer solution acting on the residual oil can be calculated. The results show that the greater the elasticity of viscous-elastic fluid is, the wider the flow channel is, the greater the horizontal stress difference is. The force acting on residual oil by viscous-elastic fluid can be increased by increasing the concentration of the polymer solution.展开更多
With selecting lower-convected Maxwell constitutive equation, polymer solution flow equation in eccentric annulus is established. And the distribution rule of the force acting on the sucker rod by polymer solution has...With selecting lower-convected Maxwell constitutive equation, polymer solution flow equation in eccentric annulus is established. And the distribution rule of the force acting on the sucker rod by polymer solution has been gained. The result shows the eccentric ratio and the movement velocity of the sucker rod are major influence factors on the radial force. The greater the ratio is, the greater the force of sucker rod is. Then the eccentric wear is easier to appear.展开更多
Nowadays, we are in great lack of the technology theory for the storage and transportation of gas hydrate. Under this condition, after checking out related theory of these, we established the technology roadmap of the...Nowadays, we are in great lack of the technology theory for the storage and transportation of gas hydrate. Under this condition, after checking out related theory of these, we established the technology roadmap of the storage and transportation of gas hydrate by LNG technology. Study has shown that the technology of LNG is more saving than that of pipeline. Then we came out with the new idea of storage and transportation of hydrate by LNG technology.展开更多
基金funded by the Guangxi Philosophy and Social Science Research Project,grant number 24XWC002.
文摘Background:In the Chinese context,the impact of short video applications on the psychological well-being of older adults is contested.While often examined through a pathological lens of addiction,this perspective may overlook paradoxical,context-dependent positive outcomes.Therefore,the main objective of this study is to challenge the traditional Compensatory Internet Use Theory by proposing and testing a chained mediation model that explores a paradoxical pathway from social support to life satisfaction via problematic social media use.Methods:Data were collected between July and August 2025 via the Credamo online survey platform,yielding 384 valid responses from Chinese older adults aged 60 and above.Key constructs were assessed using the Social Support Rating Scale(SSRS),Bergen Social Media Addiction Scale(BSMAS),Simplified UCLA Loneliness Scale,and Satisfaction with Life Scale(SWLS).A chained mediation model was tested using stepwise regression and non-parametric bootstrapping(5000 resamples),controlling for age,gender,household income,and health status.Results:The analysis revealed a paradoxical pathway,which was clarified by a key statistical suppression effect.Social support significantly and positively predicted problematic usage(β=0.157,p=0.002).After controlling for the suppressor effect of social support,problematic usage in turn negatively predicted social connectedness(β=−0.177,p<0.001).Finally,reduced social connectedness—reflecting a state of solitude—positively predicted life satisfaction(β=−0.227,p<0.001).Conclusion:The findings suggest that for older adults with sufficient offline social support,these resources may serve a“social empowerment”function.This empowerment allows behaviors measured as“problematic usage”to be theoretically reframed as a form of“deep immersive entertainment”.This immersion appears to occur alongside a state of“high-quality solitude”,which ultimately is associated with higher life satisfaction.This study provides a novel,non-pathological theoretical perspective on the consequences of high engagement with emerging social media,offering empirical grounds for non-abstinence-based intervention strategies.
基金supported by the National Natural Science Foundation of China(grant no.82522044).
文摘Crimean-Congo hemorrhagic fever virus(CCHFV)is a highly pathogenic tick-borne virus that causes severe hemorrhagic fever with high mortality rates in humans.No licensed vaccines or efficacious antiviral therapies are currently available.Here,we identified seven heavy chain antibodies targeting CCHFV Gc,which consist of heavy-chain variable domain(VHH)fused to human IgG1 Fc region(VHHFc).These VHH-Fc antibodies exhibited neutralizing activity against both recombinant vesicular stomatitis virus(VSV)-vectored CCHFV pseudoviruses and CCHFV transcriptionand entry-competent virus-like particles(tecVLPs).Among these,N025 achieved the most potent pseudovirus neutralization,while N013 showed remarkable efficacy in tecVLP systems,with IC_(50) values of 22.7 ng/mL and 33.0 ng/mL,respectively.AlphaFold3 structural predictions revealed that all characterized VHH-Fc antibodies target epitopes within Domain Ⅱ of the Gc protein,with partial or complete overlap with the fusion loop region.Alanine scanning mutagenesis confirmed the functional significance of these epitopes,with N013 showing the highest binding energy change(ΔΔG=25.36 kcal/mol)and moderate competition with a known fusion loop-targeting antibody.Sequence conservation analysis across representative CCHFV strains from different genetic lineages demonstrated complete conservation of the N013 and N025 epitopes,suggesting potential for broad-spectrum neutralizing activity.Together,our findings provide a novel strategy for developing CCHFV therapeutics and identify promising antibody candidates that could inform future broad-spectrum antiviral development efforts.
基金supported by the National Key Research and Development Program of China (2017YFB1002502)the National Natural Science Foundation of China (81501550, 81600919, and 31771076)+5 种基金the Cross Training (Shipei) Project of High-Caliber Talents in Beijing Municipal Institutions (2017–2018)the Supplementary and Supportive Project for Teachers at Beijing Information Science and Technology University (2018–2020, 5029011103)the School Scientific Research Project at Beijing Information Science and Technology University (1825010) the Beijing Municipal Science and Technology Commission (Z161100000516165) the Shenzhen Peacock Plan (KQTD2015033016104926)the Guangdong Pearl River Talents Plan Innovative and Entrepreneurial Team grant (2016ZT06S220)
文摘Spinal cord stimulation （SCS） is a promising technique for treating disorders of consciousness （DOCs）. However, differences in the spatio-temporal responsiveness of the brain under varied SCS parameters remain unclear. In this pilot study, functional near-infrared spectroscopy was used to measure the hemodynamic responses of 10 DOC patients to different SCS frequencies （5 Hz, 10 Hz, 50 Hz, 70 Hz, and 100 Hz）. In the prefrontal cortex, a key area in consciousness circuits, we found significantly increased hemodynamic responses at 70 Hz and 100 Hz, and significantly different hemodynamic responses between 50 Hz and 70 Hz/100 Hz. In addition, the functional connectivity between prefrontal and occipital areas was significantly improved with SCS at 70 Hz. These results demonstrated that SCS modulates the hemodynamic responses and long-range connectivity in a frequency-specific manner （with 70 Hz apparently better）, perhaps by improving the cerebral blood volume and information transmission through the reticular formation-thalamus-cortex pathway.
基金the Natural Science Foundation of China(NO.81573629)。
文摘A metabonomic approach involving an ultrahigh-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry(UHPLC-FT-ICR-MS)was used to investigate the changes in the endogenous metabolites in the plasma of rats with yeast-induced pyrexia treated with Gegenqinlian decoction(GQLD),aspirin and itraconazole.The differences in the small molecule profiles of treatment using traditional Chinese medicine,etiological treatment and symptomatic treatment were elucidated.Thirty-six plasma metabolites were identified or putatively identified,and the effects of the three medicines on the thirty-six metabolites were studied.Their metabolic pathways indicated that GQLD,aspirin and itraconazole ameliorated the rats with yeast-induced pyrexia predominantly by regulating the metabolisms of phospholipid,sphingolipid,fatty acid oxidation,fatty acid amides,amino acid and glycerolipid in vivo.The pharmacodynamics and metabonomic results showed that the three medicines exhibited the therapeutic effects on pyrexia by regulating the perturbations of multiple metabolisms.The study provided a scientific basis for an in-depth understanding of the therapeutic effects of GQLD,aspirin and itraconazole on rats with yeast-induced pyrexia.
基金supported by the National Natural Science Foundation of China(81471380,31771076,81501550,91432302,31620103905,and 81501179)the Science Frontier Program of the Chinese Academy of Sciences(QYZDJSSW-SMC019)+4 种基金National Key R&D Program of China(2017YFA0105203,2017YFB1002502)Beijing Municipal Science and Technology Commission(Z161100000216152,Z161100000216139,Z171100000117002,and Z161100000516165)the Shenzhen Peacock Plan(KQTD2015033016104926)the Guangdong Pearl River Talents Plan(2016ZT06S220)Youth Innovation Promotion Association,CAS,China
文摘Neuroimaging has opened new opportunities to study the neural correlates of consciousness, and provided additional information concerning diagnosis, prognosis, and therapeutic interventions in patients with disorders of consciousness. Here, we aim to review neuroimaging studies in chronic disorders of consciousness from the viewpoint of the brain network, focusing on positron emission tomogra- phy, functional MRI, functional near-infrared spectroscopy, electrophysiology, and diffusion MRI. To accelerate basic research on disorders of consciousness and provide a panoramic view of unconsciousness, we propose that it is urgent to integrate different techniques at various spatiotemporal scales, and to merge fragmented findings into a uniform ＂Brainnetome＂ （Brain-net-ome） research framework.
基金This work was supported by the National Natural Science Foundation of China (21878178).
文摘This article investigates the performances of different extractive distillation processes intensified with dividing-wall column for separating benzene-isopropanol-water ternary mixtures.All the processes with ethylene glycol as solvent are optimized with the minimal total annual cost(TAC)as target.In order to get the global optimal solution intelligently,an improved simulated annealing algorithm is adopted,which is programmed in MATLAB and linked to Aspen Plus.The results show that the extractive dividing wall column-solvent(EDWC-S)process consisting of an extractive dividing wall column and a solvent recovery column is the best scheme.It can reduce the TAC by 28.65%and CO_(2) emissions by 32.84% compared to the conventional triple-column extractive distillation process.
文摘The present investigation reports the chemical composition of the Rhus typhina L.stem identified via mass spectrometry and NMR as gallic acid,1-O-galloyl-β-D-glucose,tryptophan,scopolin,methyl gallate,fustin,quercetin,rutin,and 1,2,3,4,6-penta-O-galloyl-β-D-glucose.The antioxidant properties and the chemical composition contents of the R.typhina L.stem grown in different regions in China were determined.To determine the antioxidant activity,a total phenolic content analysis,2,2-diphenyl-1-picrylhydrazyl radical scavenging activity assay,ferric reducing antioxidant power assay,andβ-carotene linoleic acid model system were conducted.The results showed that the Rhus typhina L.stem possessed high antioxidant capacities due to its high phenolic content.The contents of the nine isolated compounds were determined by UPLC-ESI-MS/MS.The calibration curves of the nine isolated compounds were linear within the concentration range and the average recoveries were high.The result showed that 1-Ogalloyl-β-D-glucose,gallic acid,methyl gallate,and 1,2,3,4,6-penta-O-galloyl-β-D-glucose could be the compounds mainly responsible for the antioxidant capacity of the R.typhina L.stem.This reveals that the R.typhina L.stem is a good source of antioxidants.
文摘Objective To screen the target genes that are associated with survival of breast cancer(BRCA) and explore their prognostic values and immune correlations with BRCA using multiple databases..Methods The microarray expression datasets of BRCA were downloaded from the Gene Expresssion Omnibus database(GEO) and analyzed to obtain differentially expressed genes(DEGs). Hub genes were obtained by constructing and visualizing the protein-protein interaction network of DEGs. The key gene was determined using R language, STRING, and Cytoscape, and the differential expression of the key gene was verified using external datasets The Cancer Genome Atlas(TCGA) and quantitative real-time PCR(q RT-PCR) for BRCA tissues of 37 patients. The prognostic value and immunological correlation of UBE2C in BRCA were explored using R language, TIMER, and Gene Set Enrichment Analysis(GSEA).Results Of 10 hub genes seleceed from 302 DEGS, UBE2C was identified as the gene associated with BRCA survival. The expression of UBE2C was differentially upregulated in BRCA, as verified by TCGA and q RT-PCR. Prognostic analysis revealed that UBE2C served as an independent prognostic factor. High expression of UBE2C was associated with decreased immune infiltration levels of B cells, CD4+ T cells, CD8+ T cells, macrophages, and myeloid dendritic cells in BRCA tissue. The expression of UBE2C in BRCA showed a significant correlation with immune checkpoints genes PDCD1, CD274, and CTLA4 expressions. There was a positive correlation between the expression of UBE2C and the tumor mutational burden and microsatellite instability. GSEA demonstrated that UBE2C expression significantly enriched 786 immune-related gene sets.Conclusions UBE2C expression in BRCA tissues is closely related to the BRCA immune microenvironment and showes predictive values on the survivals and prognosis of BRCA patients and the effecacy of immunotherapy. UBE2C may be an potential immune-related prognostic biomarker for BRCA.
基金Project supported by Beijing Natural Science Foundation(Grant No.1212014)the National Key Research and Development Program of China(Grant Nos.2017YFA0304900 and 2017YFA0402300)+4 种基金the National Natural Science Foundation of China(Grant Nos.11604334,11604177,and U2031125)the Key Research Program of the Chinese Academy of Sciences(Grant No.XDPB08-3)the Open Research Fund Program of the State Key Laboratory of Low-Dimensional Quantum Physics(Grant No.KF201807)the Fundamental Research Funds for the Central UniversitiesYouth Innovation Promotion Association CAS。
文摘We have theoretically and experimentally studied the dispersive signal of the Rydberg atomic electromagneticallyinduced transparency(EIT)Autler–Townes(AT)splitting spectra obtained using amplitude modulation of the microwave(MW)electric field.In addition to the two zero-crossing points interval△f_(zeros),the dispersion signal has two positive maxima with an interval defined as the shoulder interval△f_(sho),which is theoretically expected to be used to measure a much weaker MW electric field.The relationship of the MW field strength E_(MW)and△f_(sho)is experimentally studied at the MW frequencies of 31.6 GHz and 9.2 GHz respectively.The results show that△f_(sho)can be used to characterize the much weaker E_(MW)than that of△f_(zeros)and the traditional EIT–AT splitting interval△f_(m);the minimum E_(MW)measured by△f_(sho)is about 30 times smaller than that by△f_(m).As an example,the minimum E_(MW)at 9.2 GHz that can be characterized by△f_(sho)is 0.056 mV/cm,which is the minimum value characterized by the frequency interval using a vapor cell without adding any auxiliary fields.The proposed method can improve the weak limit and sensitivity of E_(MW)measured by the spectral frequency interval,which is important in the direct measurement of weak E_(MW).
基金The research was funded by Science and Technology Project of Hebei Education Department(Project Number:QN2022198).Y.C.received the grant.
文摘This study aims to improve the performances of the high-pressure water descaling technology used in steel hot rolling processes.In particular,a 2050 mm hot rolling line is considered,and the problem is investigated by means of a fluid–structure interaction(FSI)method by which the descaling effect produced by rolling coils with different section sizes is examined.Assuming a flat fan-shaped nozzle at the entrance of the R1R2 roughing mill,the outflow field characteristics and the velocity distribution curve on the strike line(at a target distance of 30–120 mm)are determined.It is found that the velocity in the center region of the water jet with different target distances is higher than that in the boundary region.As the target distance increases,the velocity of the water jet in the central region decreases.Through comparison with experimental results,it is shown that the simulation model can accurately predict the impact position of the high-pressure water on the impact plate,thereby providing a computational scheme that can be used to optimize the nozzle space layout and improve the slabs’descent effect for different rolling specifications.
基金funded by Science and Technology Project of Hebei Education Department(Project No.QN2022198).
文摘Gases containing sulfur oxides can cause corrosion and failure of bellows used as furnace blowers in high-temperature environments.In order to mitigate this issue,the behavior of an effective blast furnace blower has been examined in detail.Firstly,the Sereda corrosion model has been introduced to simulate the corrosion rate of the related bellows taking into account the effects of temperature and SO_(2) gas;such results have been compared with effective measurements;then,the average gas velocity in the pipeline and the von Mises stress distribution of the inner draft tube have been analyzed using a Fluid-Structure Interaction model.Finally,the semi-closed internal corrosion environment caused by a 5 mm radial gap between the inner draft tube and the bellows has been considered.The gas flow rate in the residential space has been found to be low(0.5 ms–this value leads to a stable semi-closed internal corrosion environment for exhaust gas exchange);water phase in the exhaust gas is prone to accelerate the corrosion rate.On this basis,a bellows with an optimized inner draft tube has proposed,which includes corrosion-resistant honeycomb buffer rings.
文摘In order to analyze the microscopic theory of viscous-elastic fluid flooding residual oil, the flow equation of polymer solution in the micro pore can be derived by selecting upper-convected Maxwell constitutive equation, continuity equation and motion equation. Then, the flow velocity field and stress field can be calculated under the boundary condition, and with the theory of stress tensor, the horizontal stress difference of polymer solution acting on the residual oil can be calculated. The results show that the greater the elasticity of viscous-elastic fluid is, the wider the flow channel is, the greater the horizontal stress difference is. The force acting on residual oil by viscous-elastic fluid can be increased by increasing the concentration of the polymer solution.
文摘With selecting lower-convected Maxwell constitutive equation, polymer solution flow equation in eccentric annulus is established. And the distribution rule of the force acting on the sucker rod by polymer solution has been gained. The result shows the eccentric ratio and the movement velocity of the sucker rod are major influence factors on the radial force. The greater the ratio is, the greater the force of sucker rod is. Then the eccentric wear is easier to appear.
文摘Nowadays, we are in great lack of the technology theory for the storage and transportation of gas hydrate. Under this condition, after checking out related theory of these, we established the technology roadmap of the storage and transportation of gas hydrate by LNG technology. Study has shown that the technology of LNG is more saving than that of pipeline. Then we came out with the new idea of storage and transportation of hydrate by LNG technology.
