目的:基于网络药理学和分子对接技术,探讨经验方归元膏的活性成分防治慢性疲劳综合征(CFS)的潜在机制。方法:从TCMSP数据库、BATMAN数据库筛选归元膏的化学成分和靶点,通过GeneCards、OMIM、DisGenet数据库检索收集CFS靶点,将归元膏作...目的:基于网络药理学和分子对接技术,探讨经验方归元膏的活性成分防治慢性疲劳综合征(CFS)的潜在机制。方法:从TCMSP数据库、BATMAN数据库筛选归元膏的化学成分和靶点,通过GeneCards、OMIM、DisGenet数据库检索收集CFS靶点,将归元膏作用靶点和疾病靶点取交集,使用Cytoscape Version 3.9.1制做药物和疾病靶点韦恩图,运用STRING数据库构建蛋白质与蛋白质相互作用的PPI网络作用图,并通过Cytoscape3.8.2软件中的插件CytoNCA筛选关键靶点,并将交集靶点导入David数据库,利用微生信程序进行基因本体(GO)和京都和基因组百科全书(KEGG)富集分析,并通过Cytoscape3.8.2构建归元膏药物–有效成分–靶点和归元膏药物–成分–靶点–通路网络,最后用AutoDock vinna软件进行分子对接验证。结果:检索出归元膏活性成分有111个,其中quercetin,isoflavanone,poriferasta-7,22E-dien-3beta-ol,hancinol,orchinol等为归元膏防治CFS的关键成分,CFS相关靶点507个,其中IL-6 (白细胞介素-6),TNF (肿瘤坏死因子),STAT3 (信号转导及转录激活因子3),JUN,BCL2 (B细胞淋巴瘤/白血病-2),HIF1A (缺氧诱导因子1α亚单位),AKT1 (AKT丝氨酸/苏氨酸激酶1),CASP3 (caspase-3),MMP9 (基质金属蛋白酶9),NFKB1 (核因子kappa B亚基1)为防治CFS的关键靶点,GO富集分析示生物学过程方面可能通过对凋亡过程的负调控、细胞增殖的正调控、蛋白质磷酸化的正调控、内皮细胞增殖的正调控等,分子功能主要包括酶结合、受体结合、蛋白酶结合等;细胞功能主要包含线粒体、蛋白质复合物、细胞内膜结合的细胞器等。KEGG富集分析一共得到186条信号通路,主要与PI3K-Akt通路、卡波西肉瘤相关疱疹病毒感染、丝裂原活化蛋白激酶信号通路等有关。分子对接结果表明归元膏中的核心作用靶点和主要活性成分具备稳定性的结合活性。结论:归元膏将quercetin、poriferasta-7,22E-dien-3beta-ol、orchinol、isoflavanone等关键活性成分与IL6、TNF、STAT3、JUN、BCL2、HIF1A、AKT1和CASP3等靶点结合,通过对PI3K/Akt、MAPK、NF-κB等多条信号通路的调控,调节了CFS患者的免疫反应、细胞凋亡、代谢紊乱等多个生物学过程。通过激活抗凋亡通路、抑制促炎因子的产生和调节能量代谢,验证了该方多靶点多线路的调控,发挥了多靶点、多通路的协同作用,显著改善了CFS的症状。Objective: Based on network pharmacology and molecular docking technology, this study explores the potential mechanisms of active ingredients in the empirical formula Guiyuan Ointment for the prevention and treatment of chronic fatigue syndrome (CFS). Methods: Chemical components and targets of Guiyuan Ointment were screened from the TCMSP database and BATMAN database. CFS targets were collected through GeneCards, OMIM, and DisGenet databases. The intersection of Guiyuan Ointment’s action targets and disease targets was taken. Cytoscape Version 3.9.1 was used to create a Venn diagram of drug and disease targets. The STRING database was employed to construct a protein-protein interaction (PPI) network diagram, and key targets were screened using the CytoNCA plugin in Cytoscape 3.8.2 software. The intersection targets were imported into the David database, and gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed using the microbioinformatics program. Cytoscape 3.8.2 was used to construct the Guiyuan Ointment drug-effective component-target and drug-component-target-pathway networks. Finally, molecular docking validation was conducted using AutoDock Vina software. Results: A total of 111 active components of Guiyuan Ointment were retrieved, among which quercetin, isoflavanone, poriferasta-7,22E-dien-3beta-ol, hancinol, and orchinol are key components for the prevention and treatment of CFS by Guiyuan Ointment. There are 507 CFS-related targets, with IL-6 (interleukin-6), TNF (tumor necrosis factor), STAT3 (signal transducer and activator of transcription 3), JUN, BCL2 (B-cell lymphoma/leukemia-2), HIF1A (hypoxia-inducible factor 1α subunit), AKT1 (AKT serine/threonine kinase 1), CASP3 (caspase-3), MMP9 (matrix metallopeptidase 9), and NFKB1 (nuclear factor kappa B subunit 1) being key targets for the prevention and treatment of CFS. GO enrichment analysis showed that in terms of biological processes, it may involve negative regulation of apoptosis, positive regulation of cell proliferation, positive regulation of protein phosphorylation, and positive regulation of endothelial cell proliferation, etc. The main molecular functions include enzyme binding, receptor binding, and protease binding, etc. The main cellular functions involve mitochondria, protein complexes, and cell organelles bound to the intracellular membrane, etc. KEGG enrichment analysis yielded a total of 186 signaling pathways, mainly related to the PI3K-Akt pathway, Kaposi’s sarcoma-associated herpesvirus infection, and mitogen-activated protein kinase signaling pathway, etc. The molecular docking results indicated that the core action targets and main active components in Guiyuan Ointment have stable binding activity. Conclusion: Guiyuan Ointment combines key active components such as quercetin, poriferasta-7,22E-dien-3beta-ol, orchinol, and isoflavanone with targets like IL6, TNF, STAT3, JUN, BCL2, HIF1A, AKT1, and CASP3. By regulating multiple signaling pathways such as PI3K/Akt, MAPK, and NF-κB, it modulates various biological processes in CFS patients, including immune response, cell apoptosis, and metabolic disorders. Through activating anti-apoptotic pathways, inhibiting the production of pro-inflammatory factors, and regulating energy metabolism, it verifies the multi-target and multi-pathway regulation of this formula, exerting synergistic effects on multiple targets and pathways, and significantly improving the symptoms of CFS.展开更多
The current dialogue system can be sensitive to the emotions in the user's words,generating an empathetic response to help calm the user's emotions.But in some cases,eliciting empathetic responses may not adeq...The current dialogue system can be sensitive to the emotions in the user's words,generating an empathetic response to help calm the user's emotions.But in some cases,eliciting empathetic responses may not adequately mitigate the adverse effects that the current conversation topic is having on users.The dialogue system will continue the conversation with the user under this uncomfortable topic,which will lead to a worse chat situation or even an impasse.To solve this problem,a dialogue system that can change the topic autonomously according to the user's emotions is proposed in this paper.Specifically,the dialogue system first collects the emotional semantic information of the users and then detects it according to the emotion classification module.Once the detection results show that the user is in a bad mood,the topic change module selects a new topic from the context to shift to and generates a response.This not only helps to calm the user's mood but also move the conversation to a new area,steering the user away from the uncomfortable topic.The experimental results show that the proposed method incurs less cost in terms of content quality,but improves the emotional perception ability.Additionally,it endows the dialogue system with the ability to change the topic,and improves the user's dialogue experience.展开更多
The transition energies of the 1s^(2)2s^(2)S_(1/2)→1s^(2)2p^(2)p_(1/2,3/2)transitions in Li-like Th87+ions were calculated by combining the multi-configuration Dirac-Hartree-Fock(MCDHF)method with the model-quantum e...The transition energies of the 1s^(2)2s^(2)S_(1/2)→1s^(2)2p^(2)p_(1/2,3/2)transitions in Li-like Th87+ions were calculated by combining the multi-configuration Dirac-Hartree-Fock(MCDHF)method with the model-quantum electrodynamics(modelQED)approach.The effects of electron correlation,Breit interaction,and QED effects were analyzed in detail.The isotope shifts,including the mass shifts and field shifts,due to the 2s2S_(1/2)→2p^(2)P_(1/2,3/2)transitions were then calculated using two different methods,namely,the MCDHF method and the finite-field method.The results show that these two methods are in excellent agreement.展开更多
With the continuous improvement of the medical industry’s requirements for the professional capabilities of nursing talents,traditional nursing teaching models can hardly meet the needs of complex nursing work in neu...With the continuous improvement of the medical industry’s requirements for the professional capabilities of nursing talents,traditional nursing teaching models can hardly meet the needs of complex nursing work in neurology.This paper focuses on nursing education for neurology nursing students and explores the construction of the“one-on-one”teaching model,aiming to achieve a paradigm shift in nursing education.By analyzing the current status of neurology nursing education,this paper identifies the problems in traditional teaching models.Combining the advantages of the“one-on-one”teaching model,it elaborates on the construction path of this model from aspects such as the selection and training of teaching instructors,the design of teaching content,the innovation of teaching methods,and the improvement of the teaching evaluation system.The research shows that the“one-on-one”teaching model can significantly enhance nursing students’mastery of professional knowledge,clinical operation skills,communication skills,and emergency response capabilities,as well as strengthen their professional identity and sense of responsibility.It provides an effective way to cultivate high-quality nursing talents who can meet the needs of neurology nursing work and promotes the innovative development of nursing education.展开更多
National Fire codes,mandated by government authorities to tackle technical challenges in fire prevention and control,establish fundamental standards for construction practices.International collaboration in fire prote...National Fire codes,mandated by government authorities to tackle technical challenges in fire prevention and control,establish fundamental standards for construction practices.International collaboration in fire protection technologies has opened avenues for China to access a wealth of documents and codes,which are crucial in crafting regulations and developing a robust,scientific framework for fire code formulation.However,the translation of these codes into Chinese has been inadequate,thereby diminishing the benefits of technological exchange and collaborative learning.This underscores the necessity for comprehensive research into code translation,striving for higher-quality translations guided by established translation theories.In this study,we translated the initial segment of the NFPA 1 Fire Code into Chinese and examined both the source text and target text through the lens of Translation Shift Theory,a concept introduced by Catford.The conclusion culminated in identifying four key shifts across various linguistic levels:lexis,sentences,and groups,to ensure an accurate and precise translation of fire codes.This study offers a through and lucid explanation of how the translator integrates Catford’s theories to solve technical challenges in NFPA 1 Fire Code translation,and establish essential standards for construction translation practices.展开更多
Highly accurate international height reference frames with long-term stability,global consistency,and homogeneity are crucial for monitoring sea level variations,understanding climate change,managing disasters,and sup...Highly accurate international height reference frames with long-term stability,global consistency,and homogeneity are crucial for monitoring sea level variations,understanding climate change,managing disasters,and supporting other applications that benefit scientific research and societal well-being.Currently,there are over 100 local height reference systems worldwide.Unifying these systems is a pivotal step toward constructing international height reference frames.The method introduced in this study-the gravity frequency shift via Satellite Frequency Signal Transfer(SFST)-represents a groundbreaking relativistic geodetic approach,demonstrating its potential to surpass the constraints of conventional techniques.The advent of high-precision optical atomic clocks(OAC)with an accuracy level of 1×10^(-18) has facilitated this method's implementation.The International Association of Geodesy(IAG)has established the International Height Reference System(IHRS)and its practical realization,the International Height Reference Frame(IHRF).Our study focuses on two neighbouring height systems:the China Height System(CHS)and the Nepal Height System(NHS),separated by the Himalayas and the Xizang plateau.We aim to unify these two systems by determining the geopotential and orthometric height differences between their respective height datum stations:the Qingdao Height Datum Station(QHDS)and the Madar Height Datum Station(MHDS)using a simulation experiment with the method mentioned above.Using an OAC with an accuracy of 1×10^(-18),we identified a geopotential difference of-8.348±0.464 m^(2)s^(-2) and an orthometric height difference of 0.786±0.047 m between QHDS and MHDS.These results suggest that the introduced method could unify any two height systems with fewcentimeter-level precision,emphasizing its significance in contributing to the construction of the IHRS/IHRF with today's required precision.In summary,the SFST technique is a novel geodetic method that offers an alternative for height system unification,delivering centimeter-level precision,surpassing traditional methods,and supporting the development of the IHRF.展开更多
The degradation and nonlinear interactions of a two-breather solution of the Mel’nikov equation are analyzed.By modulating the phase shift and limit method,we prove that in different regions near the non-singular bou...The degradation and nonlinear interactions of a two-breather solution of the Mel’nikov equation are analyzed.By modulating the phase shift and limit method,we prove that in different regions near the non-singular boundaries,there are four kinds of solutions with repulsive interaction or attractive interaction in addition to the two-breather solution.They are the interaction solution between soliton and breather,the two-soliton solution,and the two-breather solution with small amplitude,which all exhibit repulsive interactions;and the two-breather solution with small amplitude,which exhibits attractive interaction.Interestingly,a new breather acts as a messenger to transfer energy during the interaction between two breather solutions with small amplitude.展开更多
The phenomenon of verbal-to-nominal shift(hereafter referred to as“V-N shift”)exists in both English and Chinese.It reflects both the universal conceptual metonymic thinking and the principle of linguistic economy.F...The phenomenon of verbal-to-nominal shift(hereafter referred to as“V-N shift”)exists in both English and Chinese.It reflects both the universal conceptual metonymic thinking and the principle of linguistic economy.Focusing on conceptual metonymy theory and combined with the Event Idealized Cognitive Model(ICM),this paper systematically compares the V-N shift phenomenon in English and Chinese.The study shows that English and Chinese V-N shifts share the core cognitive mechanism of“conceptual proximity within the Event ICM”,while significant differences exist in type distribution and usage frequency.This analysis not only helps deepen the understanding of the cognitive logic behind English and Chinese V-N shifts but also provides a new perspective for the study of word-class conversion and the relationship between language and thinking.展开更多
Anthropogenic climate change is altering species distributions globally.While species distributions are expected to shift to higher latitudes and elevations under global warming,empirical evidence on distribution shif...Anthropogenic climate change is altering species distributions globally.While species distributions are expected to shift to higher latitudes and elevations under global warming,empirical evidence on distribution shifts is mixed,and factors mediating the direction and magnitude of range shifts remain unclear.Using a dataset of 132new provincial records for 96 resident bird species from 2000 to 2023,we measured geographic distance,latitudinal shift,and temperature shift from each new record to the historical range for each species to test for poleward shifts.We assessed taxonomic variation in the magnitude of range shifts and used phylogenetic generalized linear mixed models to quantify relationships between species traits and the extent of range shifts.Our results revealed that new records occurred at a mean geographic distance of 420 km from historical ranges,with mean latitudinal shifts of+1.68°(poleward)and temperature shifts of-1.33℃(toward colder climates).The magnitude of geographic range shifts was strongly constrained by phylogenetic relatedness.Habitat breadth,habitat openness,and centroid latitude of historical ranges emerged as significant predictors of range shifts.Our results suggest that resident bird species'geographic ranges in China are shifting poleward,but the magnitude of these shifts is non-random across lineages.Species with broader habitat preferences and those from warmer climates are more likely to shift farther from their historical ranges and toward higher latitudes.This study emphasizes taxonomic variation in species range shifts and highlights the need for species-and site-specific conservation strategies under global warming.展开更多
Gait recognition,a promising biometric technology,relies on analyzing individuals' walking patterns and offers a non-intrusive and convenient approach to identity verification.However,gait recognition accuracy is ...Gait recognition,a promising biometric technology,relies on analyzing individuals' walking patterns and offers a non-intrusive and convenient approach to identity verification.However,gait recognition accuracy is often compromised by external factors such as changes in viewpoint and attire,which present substantial challenges in practical applications.To enhance gait recognition performance under diverse viewpoints and complex conditions,a global-local part-shift network is proposed in this paper.This framework integrates two novel modules:the part-shift feature extractor and the dynamic feature aggregator.The part-shift feature extractor strategically shifts body parts to capture the intrinsic relationships between non-adjacent regions,enriching the recognition process with both global and local spatial features.The dynamic feature aggregator addresses long-range dependency issues by incorporating multi-range temporal modeling,effectively aggregating information across parts and time steps to achieve a more robust recognition outcome.Comprehensive experiments on the CASIA-B dataset demonstrate that the proposed global-local part-shift network delivers superior performance compared with state-of-the-art methods,highlighting its potential for practical deployment.展开更多
We investigate theoretically the effects of chirped laser pulses on high-order harmonic generation(HHG)from solids.We find that the harmonic spectra display redshifts for the driving laser pulses with negative chirp a...We investigate theoretically the effects of chirped laser pulses on high-order harmonic generation(HHG)from solids.We find that the harmonic spectra display redshifts for the driving laser pulses with negative chirp and blueshifts for those with positive chirp,which is due to the change in the instantaneous frequency of the driving laser for different chirped pulses.The analysis of crystal-momentum-resolved(k-resolved)HHG reveals that the frequency shifts are equal for the harmonics generated by different crystal momentum channels.The frequency shifts in the cutoff region are larger than those in the plateau region.With the increase of the absolute value of the chirp parameters,the frequency shifts of HHG become more significant,leading to the shifts from odd-to even-order harmonics.We also demonstrate that the frequency shifts of harmonic spectra are related to the duration of the chirped laser field,but are insensitive to the laser intensity and dephasing time.展开更多
An enhanced understanding of the history of the western Qinling-Dabie orogen is pivotal in reconstructing geological processes of the east Asian mainland.However,less attention has been paid to its early-stage uplift-...An enhanced understanding of the history of the western Qinling-Dabie orogen is pivotal in reconstructing geological processes of the east Asian mainland.However,less attention has been paid to its early-stage uplift-erosion history after closure of surrounding oceanic basins at the mid-Paleozoic.In this study,we undertook a comprehensive study including paleocurrent reconstruction,sandstone petrology,and detrital zircon U-Pb dating on Late Carboniferous to Early Permian successions in the southern Ordos neighboring the northern Qinling-Dabie.New provenance data reveal a significant provenance shift at the Carboniferous-Permian transition.The older Benxi Formation was sourced southerly from the North Qinling Terrane that provided detritus mostly of Neoproterozoic and Early Paleozoic ages.In contrast,Early Permian samples yield age relation dominated by Neoarchean,Paleoproterozoic,Early Paleozoic,and Late Paleozoic age populations,with a significant gap of ca.1600-550 Ma,implying a sediment derivation from the Inner Mongolia Continental Arc.This shift is further verified by paleocurrent transition from south to north then.We suggest that the North Qinling Terrane experienced a significant uplift history from ca.500 Ma and remained as a highland until end-Carboniferous.From Early Permian,the North Qinling Terrane was submerged,covered by widespread deltaic sedimentation there.Northerly source from the Inner Mongolia Continental Arc began to be accumulated in the northern flank of the North Qinling Terrane,before termination approximately along the southern North Qinling Terrane,where shallow-water carbonate shelf sedimentation sustained from Devonian to Triassic.This new finding indicates that uplift of the North Qinling Terrane lasted about 150 Ma after the Proto-Tethys Ocean closure.展开更多
The aggressive nature and high mortality rate of lung cancer underscore the imperative need for early diagnosis of the disease.Thus,aminopeptidase N(APN),a potential biomarker for lung cancer,should be thoroughly inve...The aggressive nature and high mortality rate of lung cancer underscore the imperative need for early diagnosis of the disease.Thus,aminopeptidase N(APN),a potential biomarker for lung cancer,should be thoroughly investigated in this context.This report describes the development of HA-apn,a novel near-infrared fluorescent probe,specifically engineered for the sensitive detection of endogenous APN.Characterized by its high selectivity,straightforward molecular architecture,and suitable optical properties,including a long-wavelength emission at 835 nm and a large Stokes shift of 285 nm,HA-apn had high efficacy in identifying overexpressed APN in tumor cells,which shows its potential in pinpointing malignancies.To further validate its applicability and effectiveness in facilitating the direct and enhanced visualization of pulmonary alterations,an in situ lung cancer mouse model was employed.Notably,HAapn was applied for in vivo imaging of APN activity in the lung cancer mouse model receiving the probe through aerosol inhalation,and rapid and precise diagnostic results were achieved within 30min postadministration.Overall,HA-apn can be applied as an effective,non-intrusive tool for the rapid and accurate detection of pulmonary conditions.展开更多
Marine heatwaves(MHWs),which can exert devastating socioeconomic and ecological impacts,have attracted much public interest in recent years.In this study,we evaluate the sub-seasonal forecast skill of MHWs based on th...Marine heatwaves(MHWs),which can exert devastating socioeconomic and ecological impacts,have attracted much public interest in recent years.In this study,we evaluate the sub-seasonal forecast skill of MHWs based on the Nanjing University of Information Science&Technology Climate Forecast System version 1.1(NUIST CFS1.1)and analyze the related physical processes.Our results show that the model can accurately forecast the occurrence of MHWs on a global scale out to a lead time of 25 days.Notably,even at lead times of 51–55 days,the forecast skill in most tropical regions,as well as in the northeastern and southeastern Pacific,is superior to both random forecasts and persistence forecasts.Accurate predictions of sea level pressure,zonal currents,and mixed-layer depth are important for MHW forecasting.Furthermore,we also conduct forecast skill assessments for two well-documented MHW events.Due to its ability to correctly forecast the changes in heat flux anomalies at a lead time of 25 days,the model can accurately forecast the strong MHW event that occurred in the South China Sea in May–October 2020.However,the forecasting results were less than optimal for the strong MHW event that occurred along the Australian west coast in January–April 2011.Although the model accurately forecasts its occurrence,the forecast of its intensity is poor.Additionally,when the lead time exceeds 10 days,forecasts of the relevant physical processes of this MHW event are also inaccurate.展开更多
Against the backdrop of climate change,the activity of tropical cyclones(TCs)has captured widespread attention.Observational datasets indicate a declining trend in the genesis longitude of western North Pacific(WNP)TC...Against the backdrop of climate change,the activity of tropical cyclones(TCs)has captured widespread attention.Observational datasets indicate a declining trend in the genesis longitude of western North Pacific(WNP)TCs.This study investigates the zonal changes of WNP TCs with CMIP6-HighResMIP models.These models capture the genesis density of WNP TCs fairly well.The results reveal a westward shift in TC genesis longitude.This trend is associated with the significant reduction in the TC frequency over the southeastern WNP.The study also discusses changes in large-scale circulation patterns and the impact of the strengthening Pacific Walker circulation.展开更多
Amid overlapping crises and uncertainties as the world enters an era of turbulence and transformation,the countries of the Global South are swiftly emerging from the periphery of world politics to the forefront of int...Amid overlapping crises and uncertainties as the world enters an era of turbulence and transformation,the countries of the Global South are swiftly emerging from the periphery of world politics to the forefront of international cooperation,playing an increasingly vital role in advancing humanity’s collective progress.展开更多
Potassium(K)is known to enhance the catalytic performance of Fe-based catalysts in the reverse water-gas shift(rWGS)reaction,which is highly relevant during Fischer-Tropsch(FT)synthesis of CO_(2)-H_(2) mixtures.To elu...Potassium(K)is known to enhance the catalytic performance of Fe-based catalysts in the reverse water-gas shift(rWGS)reaction,which is highly relevant during Fischer-Tropsch(FT)synthesis of CO_(2)-H_(2) mixtures.To elucidate the mechanistic role of K promoter,we employed density functional theory(DFT)calculations in conjunction with microkinetic modelling for two representative surface terminations of Hägg carbide(χ-Fe_(5)C_(2)),i.e.,(010)and(510).K_(2)O results in stronger adsorption of CO_(2)and H_(2) on Hägg carbide and promotes C–O bond dissociation of adsorbed CO_(2)by increasing the electron density on Fe atoms close to the promoter oxide.The increased electron density of the surface Fe atoms results in an increased electron-electron repulsion with bonding orbitals of adsorbed CO_(2).Microkinetics simulations predict that K_(2)O increases the CO_(2)conversion during CO_(2)-FT synthesis.K_(2)O also enhances CO adsorption and dissociation,facilitating the formation of methane,used here as a proxy for hydrocarbons formation during CO_(2)-FT synthesis.CO dissociation and O removal via H_(2)O compete as the rate-controlling steps in CO_(2)-FT.展开更多
Agricultural greenhouse gas(GHG)emissions are influenced by a combination of climate,soil and agricultural management practices.Over the past 30 years,approximately 5% of China's cropland has shifted from the sout...Agricultural greenhouse gas(GHG)emissions are influenced by a combination of climate,soil and agricultural management practices.Over the past 30 years,approximately 5% of China's cropland has shifted from the south to the north.This shift has significantly altered the geographical environment,with potential substantial impacts on agricultural GHG emissions.This study used the DeNitrification DeComposition(DNDC)process-based model to simulate GHG emissions(CH_(4)and N_(2)O)from the production of China's 10 major food crops and explored changes in agricultural GHG emissions caused by the spatial shift of cropland in China.Results from the validated DNDC model indicate that total emissions from the major food crop production in China were approximately 343 Tg CO_(2)-eq yr^(-1)with CH_(4)emissions accounting for about 74%.Meanwhile,the spatial shift of cropland from 1990 to 2020 resulted in a 3% decrease in average CH_(4)emissions per unit cropland area and an 8% increase in average N_(2)O emissions per unit cropland area,respectively.The expansion of dryland in the Northwest Arid Region emitted less CH_(4)but significantly more N_(2)O,thereby driving changes in national GHG emissions.This study provides a scientific foundation for the sustainable use of cropland and the formulation of strategies to reduce agricultural GHG emissions.展开更多
Red fluorescent proteins with large Stokes shift(LSS-RFPs)are advantageous for multicolor imaging applications that allow simultaneous visualizations of multiple biological events.But it is difficult to develop LSS-RF...Red fluorescent proteins with large Stokes shift(LSS-RFPs)are advantageous for multicolor imaging applications that allow simultaneous visualizations of multiple biological events.But it is difficult to develop LSS-RFPs by extending the emission wavelength of RFPs to far-red region.Here,we employed Forster resonance energy transfer(FRET)strategy to engineer the far-red fluorescent proteins with large Stokes shift.LSS-m Apple and LSS-mCherry were constructed by fusing HaloTag to m Apple and mCherry,allowing the fluorophore TMSi R to be connected to these RFPs.FRET between RFPs and TMSi R enabled them to apply the excitation of donor RFPs to emit far-red fluorescence of acceptor TMSi R.The Stokes shifts of LSS-m Apple and LSS-mCherry were 97 nm and 75 nm,respectively.The high FRET efficiency of LSS-mCherry(E_(FRET)=83.7%)can greatly reduce the fluorescence from the donor channel,which did not affect co-imaging with mCherry.In addition,LSS-mCherry also showed excellent photostability(t_(1/2)=449.3 s),enabling stable confocal fluorescence imaging for 15 min under continuous strong excitation.Furthermore,LSS-mCherry was applied for fluorescence labeling and imaging of the nucleus,mitochondria,lysosomes,and endoplasmic reticulum in living cells.Finally,we applied LSS-mCherry to perform multi-color bioimaging of 2–4 channels,and there was no obvious crosstalk between these channels.展开更多
文摘目的:基于网络药理学和分子对接技术,探讨经验方归元膏的活性成分防治慢性疲劳综合征(CFS)的潜在机制。方法:从TCMSP数据库、BATMAN数据库筛选归元膏的化学成分和靶点,通过GeneCards、OMIM、DisGenet数据库检索收集CFS靶点,将归元膏作用靶点和疾病靶点取交集,使用Cytoscape Version 3.9.1制做药物和疾病靶点韦恩图,运用STRING数据库构建蛋白质与蛋白质相互作用的PPI网络作用图,并通过Cytoscape3.8.2软件中的插件CytoNCA筛选关键靶点,并将交集靶点导入David数据库,利用微生信程序进行基因本体(GO)和京都和基因组百科全书(KEGG)富集分析,并通过Cytoscape3.8.2构建归元膏药物–有效成分–靶点和归元膏药物–成分–靶点–通路网络,最后用AutoDock vinna软件进行分子对接验证。结果:检索出归元膏活性成分有111个,其中quercetin,isoflavanone,poriferasta-7,22E-dien-3beta-ol,hancinol,orchinol等为归元膏防治CFS的关键成分,CFS相关靶点507个,其中IL-6 (白细胞介素-6),TNF (肿瘤坏死因子),STAT3 (信号转导及转录激活因子3),JUN,BCL2 (B细胞淋巴瘤/白血病-2),HIF1A (缺氧诱导因子1α亚单位),AKT1 (AKT丝氨酸/苏氨酸激酶1),CASP3 (caspase-3),MMP9 (基质金属蛋白酶9),NFKB1 (核因子kappa B亚基1)为防治CFS的关键靶点,GO富集分析示生物学过程方面可能通过对凋亡过程的负调控、细胞增殖的正调控、蛋白质磷酸化的正调控、内皮细胞增殖的正调控等,分子功能主要包括酶结合、受体结合、蛋白酶结合等;细胞功能主要包含线粒体、蛋白质复合物、细胞内膜结合的细胞器等。KEGG富集分析一共得到186条信号通路,主要与PI3K-Akt通路、卡波西肉瘤相关疱疹病毒感染、丝裂原活化蛋白激酶信号通路等有关。分子对接结果表明归元膏中的核心作用靶点和主要活性成分具备稳定性的结合活性。结论:归元膏将quercetin、poriferasta-7,22E-dien-3beta-ol、orchinol、isoflavanone等关键活性成分与IL6、TNF、STAT3、JUN、BCL2、HIF1A、AKT1和CASP3等靶点结合,通过对PI3K/Akt、MAPK、NF-κB等多条信号通路的调控,调节了CFS患者的免疫反应、细胞凋亡、代谢紊乱等多个生物学过程。通过激活抗凋亡通路、抑制促炎因子的产生和调节能量代谢,验证了该方多靶点多线路的调控,发挥了多靶点、多通路的协同作用,显著改善了CFS的症状。Objective: Based on network pharmacology and molecular docking technology, this study explores the potential mechanisms of active ingredients in the empirical formula Guiyuan Ointment for the prevention and treatment of chronic fatigue syndrome (CFS). Methods: Chemical components and targets of Guiyuan Ointment were screened from the TCMSP database and BATMAN database. CFS targets were collected through GeneCards, OMIM, and DisGenet databases. The intersection of Guiyuan Ointment’s action targets and disease targets was taken. Cytoscape Version 3.9.1 was used to create a Venn diagram of drug and disease targets. The STRING database was employed to construct a protein-protein interaction (PPI) network diagram, and key targets were screened using the CytoNCA plugin in Cytoscape 3.8.2 software. The intersection targets were imported into the David database, and gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed using the microbioinformatics program. Cytoscape 3.8.2 was used to construct the Guiyuan Ointment drug-effective component-target and drug-component-target-pathway networks. Finally, molecular docking validation was conducted using AutoDock Vina software. Results: A total of 111 active components of Guiyuan Ointment were retrieved, among which quercetin, isoflavanone, poriferasta-7,22E-dien-3beta-ol, hancinol, and orchinol are key components for the prevention and treatment of CFS by Guiyuan Ointment. There are 507 CFS-related targets, with IL-6 (interleukin-6), TNF (tumor necrosis factor), STAT3 (signal transducer and activator of transcription 3), JUN, BCL2 (B-cell lymphoma/leukemia-2), HIF1A (hypoxia-inducible factor 1α subunit), AKT1 (AKT serine/threonine kinase 1), CASP3 (caspase-3), MMP9 (matrix metallopeptidase 9), and NFKB1 (nuclear factor kappa B subunit 1) being key targets for the prevention and treatment of CFS. GO enrichment analysis showed that in terms of biological processes, it may involve negative regulation of apoptosis, positive regulation of cell proliferation, positive regulation of protein phosphorylation, and positive regulation of endothelial cell proliferation, etc. The main molecular functions include enzyme binding, receptor binding, and protease binding, etc. The main cellular functions involve mitochondria, protein complexes, and cell organelles bound to the intracellular membrane, etc. KEGG enrichment analysis yielded a total of 186 signaling pathways, mainly related to the PI3K-Akt pathway, Kaposi’s sarcoma-associated herpesvirus infection, and mitogen-activated protein kinase signaling pathway, etc. The molecular docking results indicated that the core action targets and main active components in Guiyuan Ointment have stable binding activity. Conclusion: Guiyuan Ointment combines key active components such as quercetin, poriferasta-7,22E-dien-3beta-ol, orchinol, and isoflavanone with targets like IL6, TNF, STAT3, JUN, BCL2, HIF1A, AKT1, and CASP3. By regulating multiple signaling pathways such as PI3K/Akt, MAPK, and NF-κB, it modulates various biological processes in CFS patients, including immune response, cell apoptosis, and metabolic disorders. Through activating anti-apoptotic pathways, inhibiting the production of pro-inflammatory factors, and regulating energy metabolism, it verifies the multi-target and multi-pathway regulation of this formula, exerting synergistic effects on multiple targets and pathways, and significantly improving the symptoms of CFS.
基金Sponsored by Natural Science Foundation of Heilongjiang Provincial(Grant No.LH2023F033)Science and Technology Innovation Talent Project of Harbin(Grant No.2022CXRCCG006).
文摘The current dialogue system can be sensitive to the emotions in the user's words,generating an empathetic response to help calm the user's emotions.But in some cases,eliciting empathetic responses may not adequately mitigate the adverse effects that the current conversation topic is having on users.The dialogue system will continue the conversation with the user under this uncomfortable topic,which will lead to a worse chat situation or even an impasse.To solve this problem,a dialogue system that can change the topic autonomously according to the user's emotions is proposed in this paper.Specifically,the dialogue system first collects the emotional semantic information of the users and then detects it according to the emotion classification module.Once the detection results show that the user is in a bad mood,the topic change module selects a new topic from the context to shift to and generates a response.This not only helps to calm the user's mood but also move the conversation to a new area,steering the user away from the uncomfortable topic.The experimental results show that the proposed method incurs less cost in terms of content quality,but improves the emotional perception ability.Additionally,it endows the dialogue system with the ability to change the topic,and improves the user's dialogue experience.
基金Project supported by the National Key Research and Development Program of China(Grant No.2022YFA1602500)the National Natural Science Foundation of China(Grant Nos.1236040286,12474250,12174316,12464036,and12404306)+1 种基金the Young Teachers Scientific Research Ability Promotion Plan of Northwest Normal University(Grant No.NWNU-LKQN2020-10)the Funds for Innovative Fundamental Research Group Project of Gansu Province(Grant No.20JR5RA541)。
文摘The transition energies of the 1s^(2)2s^(2)S_(1/2)→1s^(2)2p^(2)p_(1/2,3/2)transitions in Li-like Th87+ions were calculated by combining the multi-configuration Dirac-Hartree-Fock(MCDHF)method with the model-quantum electrodynamics(modelQED)approach.The effects of electron correlation,Breit interaction,and QED effects were analyzed in detail.The isotope shifts,including the mass shifts and field shifts,due to the 2s2S_(1/2)→2p^(2)P_(1/2,3/2)transitions were then calculated using two different methods,namely,the MCDHF method and the finite-field method.The results show that these two methods are in excellent agreement.
文摘With the continuous improvement of the medical industry’s requirements for the professional capabilities of nursing talents,traditional nursing teaching models can hardly meet the needs of complex nursing work in neurology.This paper focuses on nursing education for neurology nursing students and explores the construction of the“one-on-one”teaching model,aiming to achieve a paradigm shift in nursing education.By analyzing the current status of neurology nursing education,this paper identifies the problems in traditional teaching models.Combining the advantages of the“one-on-one”teaching model,it elaborates on the construction path of this model from aspects such as the selection and training of teaching instructors,the design of teaching content,the innovation of teaching methods,and the improvement of the teaching evaluation system.The research shows that the“one-on-one”teaching model can significantly enhance nursing students’mastery of professional knowledge,clinical operation skills,communication skills,and emergency response capabilities,as well as strengthen their professional identity and sense of responsibility.It provides an effective way to cultivate high-quality nursing talents who can meet the needs of neurology nursing work and promotes the innovative development of nursing education.
基金Hangzhou Philosophy and Social Science Planning Program(24JD15)。
文摘National Fire codes,mandated by government authorities to tackle technical challenges in fire prevention and control,establish fundamental standards for construction practices.International collaboration in fire protection technologies has opened avenues for China to access a wealth of documents and codes,which are crucial in crafting regulations and developing a robust,scientific framework for fire code formulation.However,the translation of these codes into Chinese has been inadequate,thereby diminishing the benefits of technological exchange and collaborative learning.This underscores the necessity for comprehensive research into code translation,striving for higher-quality translations guided by established translation theories.In this study,we translated the initial segment of the NFPA 1 Fire Code into Chinese and examined both the source text and target text through the lens of Translation Shift Theory,a concept introduced by Catford.The conclusion culminated in identifying four key shifts across various linguistic levels:lexis,sentences,and groups,to ensure an accurate and precise translation of fire codes.This study offers a through and lucid explanation of how the translator integrates Catford’s theories to solve technical challenges in NFPA 1 Fire Code translation,and establish essential standards for construction translation practices.
基金the National Natural Science Foundation of China(NSFC)(Grant Nos.42030105,42274011,42074019,41974034,42204006)。
文摘Highly accurate international height reference frames with long-term stability,global consistency,and homogeneity are crucial for monitoring sea level variations,understanding climate change,managing disasters,and supporting other applications that benefit scientific research and societal well-being.Currently,there are over 100 local height reference systems worldwide.Unifying these systems is a pivotal step toward constructing international height reference frames.The method introduced in this study-the gravity frequency shift via Satellite Frequency Signal Transfer(SFST)-represents a groundbreaking relativistic geodetic approach,demonstrating its potential to surpass the constraints of conventional techniques.The advent of high-precision optical atomic clocks(OAC)with an accuracy level of 1×10^(-18) has facilitated this method's implementation.The International Association of Geodesy(IAG)has established the International Height Reference System(IHRS)and its practical realization,the International Height Reference Frame(IHRF).Our study focuses on two neighbouring height systems:the China Height System(CHS)and the Nepal Height System(NHS),separated by the Himalayas and the Xizang plateau.We aim to unify these two systems by determining the geopotential and orthometric height differences between their respective height datum stations:the Qingdao Height Datum Station(QHDS)and the Madar Height Datum Station(MHDS)using a simulation experiment with the method mentioned above.Using an OAC with an accuracy of 1×10^(-18),we identified a geopotential difference of-8.348±0.464 m^(2)s^(-2) and an orthometric height difference of 0.786±0.047 m between QHDS and MHDS.These results suggest that the introduced method could unify any two height systems with fewcentimeter-level precision,emphasizing its significance in contributing to the construction of the IHRS/IHRF with today's required precision.In summary,the SFST technique is a novel geodetic method that offers an alternative for height system unification,delivering centimeter-level precision,surpassing traditional methods,and supporting the development of the IHRF.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.52171251 and U21062251)Program of Science and Technology Innovation of Dalian(Grant No.2022JJ12GX036).
文摘The degradation and nonlinear interactions of a two-breather solution of the Mel’nikov equation are analyzed.By modulating the phase shift and limit method,we prove that in different regions near the non-singular boundaries,there are four kinds of solutions with repulsive interaction or attractive interaction in addition to the two-breather solution.They are the interaction solution between soliton and breather,the two-soliton solution,and the two-breather solution with small amplitude,which all exhibit repulsive interactions;and the two-breather solution with small amplitude,which exhibits attractive interaction.Interestingly,a new breather acts as a messenger to transfer energy during the interaction between two breather solutions with small amplitude.
文摘The phenomenon of verbal-to-nominal shift(hereafter referred to as“V-N shift”)exists in both English and Chinese.It reflects both the universal conceptual metonymic thinking and the principle of linguistic economy.Focusing on conceptual metonymy theory and combined with the Event Idealized Cognitive Model(ICM),this paper systematically compares the V-N shift phenomenon in English and Chinese.The study shows that English and Chinese V-N shifts share the core cognitive mechanism of“conceptual proximity within the Event ICM”,while significant differences exist in type distribution and usage frequency.This analysis not only helps deepen the understanding of the cognitive logic behind English and Chinese V-N shifts but also provides a new perspective for the study of word-class conversion and the relationship between language and thinking.
基金supported by grants from the National Natural Science Foundation of China(Grant No.32271733)Guangdong Basic and Applied Basic Research Foundation(Grant No.2023A1515011045)+1 种基金Science and Technology Projects in Guangzhou(Grant No.2023A04J0121)SCNU Training Program of Innovation for Undergraduates,China。
文摘Anthropogenic climate change is altering species distributions globally.While species distributions are expected to shift to higher latitudes and elevations under global warming,empirical evidence on distribution shifts is mixed,and factors mediating the direction and magnitude of range shifts remain unclear.Using a dataset of 132new provincial records for 96 resident bird species from 2000 to 2023,we measured geographic distance,latitudinal shift,and temperature shift from each new record to the historical range for each species to test for poleward shifts.We assessed taxonomic variation in the magnitude of range shifts and used phylogenetic generalized linear mixed models to quantify relationships between species traits and the extent of range shifts.Our results revealed that new records occurred at a mean geographic distance of 420 km from historical ranges,with mean latitudinal shifts of+1.68°(poleward)and temperature shifts of-1.33℃(toward colder climates).The magnitude of geographic range shifts was strongly constrained by phylogenetic relatedness.Habitat breadth,habitat openness,and centroid latitude of historical ranges emerged as significant predictors of range shifts.Our results suggest that resident bird species'geographic ranges in China are shifting poleward,but the magnitude of these shifts is non-random across lineages.Species with broader habitat preferences and those from warmer climates are more likely to shift farther from their historical ranges and toward higher latitudes.This study emphasizes taxonomic variation in species range shifts and highlights the need for species-and site-specific conservation strategies under global warming.
文摘Gait recognition,a promising biometric technology,relies on analyzing individuals' walking patterns and offers a non-intrusive and convenient approach to identity verification.However,gait recognition accuracy is often compromised by external factors such as changes in viewpoint and attire,which present substantial challenges in practical applications.To enhance gait recognition performance under diverse viewpoints and complex conditions,a global-local part-shift network is proposed in this paper.This framework integrates two novel modules:the part-shift feature extractor and the dynamic feature aggregator.The part-shift feature extractor strategically shifts body parts to capture the intrinsic relationships between non-adjacent regions,enriching the recognition process with both global and local spatial features.The dynamic feature aggregator addresses long-range dependency issues by incorporating multi-range temporal modeling,effectively aggregating information across parts and time steps to achieve a more robust recognition outcome.Comprehensive experiments on the CASIA-B dataset demonstrate that the proposed global-local part-shift network delivers superior performance compared with state-of-the-art methods,highlighting its potential for practical deployment.
基金Project supported by the Natural Science Foundation of Jilin Province of China(Grant No.20230101014JC)the National Natural Science Foundation of China(Grant No.12374265)。
文摘We investigate theoretically the effects of chirped laser pulses on high-order harmonic generation(HHG)from solids.We find that the harmonic spectra display redshifts for the driving laser pulses with negative chirp and blueshifts for those with positive chirp,which is due to the change in the instantaneous frequency of the driving laser for different chirped pulses.The analysis of crystal-momentum-resolved(k-resolved)HHG reveals that the frequency shifts are equal for the harmonics generated by different crystal momentum channels.The frequency shifts in the cutoff region are larger than those in the plateau region.With the increase of the absolute value of the chirp parameters,the frequency shifts of HHG become more significant,leading to the shifts from odd-to even-order harmonics.We also demonstrate that the frequency shifts of harmonic spectra are related to the duration of the chirped laser field,but are insensitive to the laser intensity and dephasing time.
基金the National Natural Science Foundation of China(Grant Nos:42372253 and 42072260)the Youth Innovation Team of Shaanxi Universitiesthe Science and Technology Project of PetroChina(No.2023ZZ0201).
文摘An enhanced understanding of the history of the western Qinling-Dabie orogen is pivotal in reconstructing geological processes of the east Asian mainland.However,less attention has been paid to its early-stage uplift-erosion history after closure of surrounding oceanic basins at the mid-Paleozoic.In this study,we undertook a comprehensive study including paleocurrent reconstruction,sandstone petrology,and detrital zircon U-Pb dating on Late Carboniferous to Early Permian successions in the southern Ordos neighboring the northern Qinling-Dabie.New provenance data reveal a significant provenance shift at the Carboniferous-Permian transition.The older Benxi Formation was sourced southerly from the North Qinling Terrane that provided detritus mostly of Neoproterozoic and Early Paleozoic ages.In contrast,Early Permian samples yield age relation dominated by Neoarchean,Paleoproterozoic,Early Paleozoic,and Late Paleozoic age populations,with a significant gap of ca.1600-550 Ma,implying a sediment derivation from the Inner Mongolia Continental Arc.This shift is further verified by paleocurrent transition from south to north then.We suggest that the North Qinling Terrane experienced a significant uplift history from ca.500 Ma and remained as a highland until end-Carboniferous.From Early Permian,the North Qinling Terrane was submerged,covered by widespread deltaic sedimentation there.Northerly source from the Inner Mongolia Continental Arc began to be accumulated in the northern flank of the North Qinling Terrane,before termination approximately along the southern North Qinling Terrane,where shallow-water carbonate shelf sedimentation sustained from Devonian to Triassic.This new finding indicates that uplift of the North Qinling Terrane lasted about 150 Ma after the Proto-Tethys Ocean closure.
基金supported by the National Natural Science Foundation of China(Nos.22004046 and 22074052)the Science and Technology Developing Foundation of Jilin Province of China(Nos.20240404044ZP,20230101033JC and 20220505015ZP).
文摘The aggressive nature and high mortality rate of lung cancer underscore the imperative need for early diagnosis of the disease.Thus,aminopeptidase N(APN),a potential biomarker for lung cancer,should be thoroughly investigated in this context.This report describes the development of HA-apn,a novel near-infrared fluorescent probe,specifically engineered for the sensitive detection of endogenous APN.Characterized by its high selectivity,straightforward molecular architecture,and suitable optical properties,including a long-wavelength emission at 835 nm and a large Stokes shift of 285 nm,HA-apn had high efficacy in identifying overexpressed APN in tumor cells,which shows its potential in pinpointing malignancies.To further validate its applicability and effectiveness in facilitating the direct and enhanced visualization of pulmonary alterations,an in situ lung cancer mouse model was employed.Notably,HAapn was applied for in vivo imaging of APN activity in the lung cancer mouse model receiving the probe through aerosol inhalation,and rapid and precise diagnostic results were achieved within 30min postadministration.Overall,HA-apn can be applied as an effective,non-intrusive tool for the rapid and accurate detection of pulmonary conditions.
基金supported by National Natural Science Foundation of China(Grant Nos.42030605 and 42088101)National Key R&D Program of China(Grant No.2020YFA0608004)High Performance Computing of Nanjing University of Information Science&Technology for their support of this work。
文摘Marine heatwaves(MHWs),which can exert devastating socioeconomic and ecological impacts,have attracted much public interest in recent years.In this study,we evaluate the sub-seasonal forecast skill of MHWs based on the Nanjing University of Information Science&Technology Climate Forecast System version 1.1(NUIST CFS1.1)and analyze the related physical processes.Our results show that the model can accurately forecast the occurrence of MHWs on a global scale out to a lead time of 25 days.Notably,even at lead times of 51–55 days,the forecast skill in most tropical regions,as well as in the northeastern and southeastern Pacific,is superior to both random forecasts and persistence forecasts.Accurate predictions of sea level pressure,zonal currents,and mixed-layer depth are important for MHW forecasting.Furthermore,we also conduct forecast skill assessments for two well-documented MHW events.Due to its ability to correctly forecast the changes in heat flux anomalies at a lead time of 25 days,the model can accurately forecast the strong MHW event that occurred in the South China Sea in May–October 2020.However,the forecasting results were less than optimal for the strong MHW event that occurred along the Australian west coast in January–April 2011.Although the model accurately forecasts its occurrence,the forecast of its intensity is poor.Additionally,when the lead time exceeds 10 days,forecasts of the relevant physical processes of this MHW event are also inaccurate.
基金supported by a key project of the National Natural Science Foundation of China[grant number 42192563]。
文摘Against the backdrop of climate change,the activity of tropical cyclones(TCs)has captured widespread attention.Observational datasets indicate a declining trend in the genesis longitude of western North Pacific(WNP)TCs.This study investigates the zonal changes of WNP TCs with CMIP6-HighResMIP models.These models capture the genesis density of WNP TCs fairly well.The results reveal a westward shift in TC genesis longitude.This trend is associated with the significant reduction in the TC frequency over the southeastern WNP.The study also discusses changes in large-scale circulation patterns and the impact of the strengthening Pacific Walker circulation.
文摘Amid overlapping crises and uncertainties as the world enters an era of turbulence and transformation,the countries of the Global South are swiftly emerging from the periphery of world politics to the forefront of international cooperation,playing an increasingly vital role in advancing humanity’s collective progress.
文摘Potassium(K)is known to enhance the catalytic performance of Fe-based catalysts in the reverse water-gas shift(rWGS)reaction,which is highly relevant during Fischer-Tropsch(FT)synthesis of CO_(2)-H_(2) mixtures.To elucidate the mechanistic role of K promoter,we employed density functional theory(DFT)calculations in conjunction with microkinetic modelling for two representative surface terminations of Hägg carbide(χ-Fe_(5)C_(2)),i.e.,(010)and(510).K_(2)O results in stronger adsorption of CO_(2)and H_(2) on Hägg carbide and promotes C–O bond dissociation of adsorbed CO_(2)by increasing the electron density on Fe atoms close to the promoter oxide.The increased electron density of the surface Fe atoms results in an increased electron-electron repulsion with bonding orbitals of adsorbed CO_(2).Microkinetics simulations predict that K_(2)O increases the CO_(2)conversion during CO_(2)-FT synthesis.K_(2)O also enhances CO adsorption and dissociation,facilitating the formation of methane,used here as a proxy for hydrocarbons formation during CO_(2)-FT synthesis.CO dissociation and O removal via H_(2)O compete as the rate-controlling steps in CO_(2)-FT.
基金National Natural Science Foundation of China,No.42361144881,No.42201310The Third Xinjiang Scientific Expedition Program,No.2021xjkk0900。
文摘Agricultural greenhouse gas(GHG)emissions are influenced by a combination of climate,soil and agricultural management practices.Over the past 30 years,approximately 5% of China's cropland has shifted from the south to the north.This shift has significantly altered the geographical environment,with potential substantial impacts on agricultural GHG emissions.This study used the DeNitrification DeComposition(DNDC)process-based model to simulate GHG emissions(CH_(4)and N_(2)O)from the production of China's 10 major food crops and explored changes in agricultural GHG emissions caused by the spatial shift of cropland in China.Results from the validated DNDC model indicate that total emissions from the major food crop production in China were approximately 343 Tg CO_(2)-eq yr^(-1)with CH_(4)emissions accounting for about 74%.Meanwhile,the spatial shift of cropland from 1990 to 2020 resulted in a 3% decrease in average CH_(4)emissions per unit cropland area and an 8% increase in average N_(2)O emissions per unit cropland area,respectively.The expansion of dryland in the Northwest Arid Region emitted less CH_(4)but significantly more N_(2)O,thereby driving changes in national GHG emissions.This study provides a scientific foundation for the sustainable use of cropland and the formulation of strategies to reduce agricultural GHG emissions.
基金supported by the National Natural Science Foundation of China(Nos.22225806,22078314,22278394,22378385)Dalian Institute of Chemical Physics(Nos.DICPI202142,DICPI202436)。
文摘Red fluorescent proteins with large Stokes shift(LSS-RFPs)are advantageous for multicolor imaging applications that allow simultaneous visualizations of multiple biological events.But it is difficult to develop LSS-RFPs by extending the emission wavelength of RFPs to far-red region.Here,we employed Forster resonance energy transfer(FRET)strategy to engineer the far-red fluorescent proteins with large Stokes shift.LSS-m Apple and LSS-mCherry were constructed by fusing HaloTag to m Apple and mCherry,allowing the fluorophore TMSi R to be connected to these RFPs.FRET between RFPs and TMSi R enabled them to apply the excitation of donor RFPs to emit far-red fluorescence of acceptor TMSi R.The Stokes shifts of LSS-m Apple and LSS-mCherry were 97 nm and 75 nm,respectively.The high FRET efficiency of LSS-mCherry(E_(FRET)=83.7%)can greatly reduce the fluorescence from the donor channel,which did not affect co-imaging with mCherry.In addition,LSS-mCherry also showed excellent photostability(t_(1/2)=449.3 s),enabling stable confocal fluorescence imaging for 15 min under continuous strong excitation.Furthermore,LSS-mCherry was applied for fluorescence labeling and imaging of the nucleus,mitochondria,lysosomes,and endoplasmic reticulum in living cells.Finally,we applied LSS-mCherry to perform multi-color bioimaging of 2–4 channels,and there was no obvious crosstalk between these channels.
