Located in northwest Beijing, Zhongguancun is often referred to as China＇s very own Silicon Valley. However, the current reputation of this neighborhood as a hub of advanced Chinese technology contrasts sharply with...Located in northwest Beijing, Zhongguancun is often referred to as China＇s very own Silicon Valley. However, the current reputation of this neighborhood as a hub of advanced Chinese technology contrasts sharply with its traditional cliched image. Only a few years ago, this place was one of the largest wholesale markets for electronic products. The way Zhongg-uancun was able to transi tion toward innovation by attracting startups continues to surprise visitors, whether Chinese or foreigners.展开更多
Based on the Regional Specialized Meteorological Center(RSMC)Tokyo-Typhoon Center best-track data and the NCEP-NCAR reanalysis dataset,extratropical transitioning(ET)tropical cyclones(ETCs)over the western North Pacif...Based on the Regional Specialized Meteorological Center(RSMC)Tokyo-Typhoon Center best-track data and the NCEP-NCAR reanalysis dataset,extratropical transitioning(ET)tropical cyclones(ETCs)over the western North Pacific(WNP)during 1951–2021 are classified into six clusters using the fuzzy c-means clustering method(FCM)according to their track patterns.The characteristics of the six hard-clustered ETCs with the highest membership coefficient are shown.Most tropical cyclones(TCs)that were assigned to clusters C2,C5,and C6 made landfall over eastern Asian countries,which severely threatened these regions.Among landfalling TCs,93.2%completed their ET after landfall,whereas 39.8%of ETCs completed their transition within one day.The frequency of ETCs over the WNP has decreased in the past four decades,wherein cluster C5 demonstrated a significant decrease on both interannual and interdecadal timescales with the expansion and intensification of the western Pacific subtropical high(WPSH).This large-scale circulation pattern is favorable for C2 and causes it to become the dominant track pattern,owning to it containing the largest number of intensifying ETCs among the six clusters,a number that has increased insignificantly over the past four decades.The surface roughness variation and three-dimensional background circulation led to C5 containing the maximum number of landfalling TCs and a minimum number of intensifying ETCs.Our results will facilitate a better understanding of the spatiotemporal distributions of ET events and associated environment background fields,which will benefit the effective monitoring of these events over the WNP.展开更多
This paper presents the views of 623 informal and formal small,medium,and micro enterprises(SMMEs)operating in the Gauteng Province of South Africa.The objective of the study was to identify challenges and benefits th...This paper presents the views of 623 informal and formal small,medium,and micro enterprises(SMMEs)operating in the Gauteng Province of South Africa.The objective of the study was to identify challenges and benefits that are experienced by SMMEs during and after the registration process leading to the transition from informal to formal business,the level of awareness by the SMMEs of the registration information,and the procedures in addition to the potential factors that inspire or discourage informal and prospective business registration.The reason for including both informal and formal SMMEs in the survey was to compare the perceptions of these groups of businesses regarding the triggers and/or barriers to register as a formal business.The results show that for both informal and formal businesses,the liability of paying taxes was a major challenge while improved workers’health and safety accrued as a major benefit.Own research emerged as the main source of access to business registration information and procedure.The costs involved in registration were highlighted as one of the major factors discouraging registration but the prospects of expanding the customer base and the ability to achieve a higher turnover as some of the main inspiring factors.The study recommends the development of policies that provide an enabling environment for sustainable enterprises but also to implement measures that improve productivity through access to finance,skills,infrastructure,markets,and technology transfers.展开更多
Original reference:iEnergy,3(1):46-58,2024 Grid-tie voltage source converters(VSCs)can operate in three distinct modes:AC-dominant,DC-dominant,and balanced,depending on the placement of the stiff voltage sources,as sh...Original reference:iEnergy,3(1):46-58,2024 Grid-tie voltage source converters(VSCs)can operate in three distinct modes:AC-dominant,DC-dominant,and balanced,depending on the placement of the stiff voltage sources,as shown in Figure 1.The distinct operation modes of VSCs typically require different synchronization control techniques.For instance,the grid-following(GFL)control,which utilizes a phase-locked loop to track the AC grid phase and frequency,can be employed for VSCs operating in the AC-dominant mode and the balanced mode.On the other hand,the grid-forming(GFM)control is uti-lized for VSCs operating in the DC-dominant mode and the bal-anced mode.Therefore,neither GFM control nor GFL control can serve as a universal synchronization control technique for VSCs to operate in all of the three modes.While the combination of the GFL VSCs and the GFM VSCs can handle applications that require the VSCs to operate in all of the three modes,effectively accommodating and coordinating the heterogeneous GFL and GFM VSCs remains challenging for power systems.展开更多
Original reference:iEnergy,2(2):93-99,2023 Droplet-based triboelectric nanogenerator(D-TENG)using liquid-solid contact electrification has been widely studied for harvesting raindrop energy and ocean energy due to its...Original reference:iEnergy,2(2):93-99,2023 Droplet-based triboelectric nanogenerator(D-TENG)using liquid-solid contact electrification has been widely studied for harvesting raindrop energy and ocean energy due to its unique ability to effectively reduce friction between solids and improve durability.In 2020,a new-generation D-TENG with a“transistor-like”struc-ture was proposed,which first achieved ultra-high instantaneous power output(50 W/m2).Subsequently,D-TENG has been rapidly developed and is widely used in ocean wave energy power gener-ation and liquid-solid triboelectric power generation.Currently,although we have excellent D-TENGs to harvest energy from a single water droplet,but if multiple D-TENGs are simply connected in parallel for a large area usage,the output power of the whole power generation module will drop significantly due to the mutual influence between different individual generation units,which severely limits their applications in practice.Therefore,finding a reasonable topology to relieve the inherent constraints of D-TENGs is of great significance for realizing the large-scale rain-drop energy harvesting.展开更多
Human pluripotent stem cells provide an inexhaustible model to study human embryogenesis in vitro.Recent studies have provided diverse models to generate human blastoids by self-organization of different pluripotent s...Human pluripotent stem cells provide an inexhaustible model to study human embryogenesis in vitro.Recent studies have provided diverse models to generate human blastoids by self-organization of different pluripotent stem cells or somatic reprogramming intermediates.However,whether blastoids can be generated from other cell types or whether they can recapitulate postimplantation development in vitro is unknown.Here,we develop a strategy to generate human blastoids from heterogeneous intermediates with epiblast,trophectoderm,and primitive endoderm signatures of the primed-to-naïve conversion process,which resemble natural blastocysts in morphological architecture,composition of cell lineages,transcriptome,and lineage differentiation potential.In addition,these blastoids reflect many features of human peri-implantation and pregastrulation development when further cultured in an in vitro 3D culture system.In summary,our study provides an alternative strategy to generate human blastoids and offers insights into human early embryogenesis by modeling peri-and postimplantation development in vitro.展开更多
Over the next 20 years,China's urban rail transit(hereinafter referred to as'urban rail')will face large-scalerenovation of existing line facilities and equipment,with more than 1000 km of renovated lines ...Over the next 20 years,China's urban rail transit(hereinafter referred to as'urban rail')will face large-scalerenovation of existing line facilities and equipment,with more than 1000 km of renovated lines to be added eachyear.In 2024,the China Association of Metros issued the Guiding Opinions on the Renovation of Existing UrbanRail Transit Lines in China,providing guiding opinions on norms,standards,and implementation approaches forthe renovation of existing lines in the coming period.In the practical work of renovating existing urban rail lines,it is necessary to continuously explore and refine relevant theoretical methods in line with industry developmenttrends and urban development requirements.The following are the author's recent reflections on theoreticalinnovation in this field.展开更多
Electrochemical water splitting represents a sustainable technology for hydrogen(H_(2))production.However,its large-scale implementation is hindered by the high overpotentials required for both the cathodic hydrogen e...Electrochemical water splitting represents a sustainable technology for hydrogen(H_(2))production.However,its large-scale implementation is hindered by the high overpotentials required for both the cathodic hydrogen evolution reaction(HER)and the anodic oxygen evolution reaction(OER).Transition metal-based catalysts have garnered significant research interest as promising alternatives to noble-metal catalysts,owing to their low cost,tunable composition,and noble-metal-like catalytic activity.Nevertheless,systematic reviews on their application as bifunctional catalysts for overall water splitting(OWS)are still limited.This review comprehensively outlines the principal categories of bifunctional transition metal electrocatalysts derived from electrospun nanofibers(NFs),including metals,oxides,phosphides,sulfides,and carbides.Key strategies for enhancing their catalytic performance are systematically summarized,such as heterointerface engineering,heteroatom doping,metal-nonmetal-metal bridging architectures,and single-atom site design.Finally,current challenges and future research directions are discussed,aiming to provide insightful perspectives for the rational design of high-performance electrocatalysts for OWS.展开更多
Dynamic thermal mechanical analysis was used to evaluate the viscoelasticity of asphalt.The parameters included the energy storage modulus(E),the loss modulus(E'),and the loss tangent(tanδ).The impact of three ki...Dynamic thermal mechanical analysis was used to evaluate the viscoelasticity of asphalt.The parameters included the energy storage modulus(E),the loss modulus(E'),and the loss tangent(tanδ).The impact of three kinds of particles containing CaCO_(3)with different size and structure on the mechanical properties was also measured.The addition of limestone increases the glass transition temperature,while nanoCaCO_(3)@SiO_(2)decreases the glass transition temperature.Nano-CaCO_(3)has a negligible effect on the glass transition temperature.The particle size of the limestone is 0.075 mm,which is a material at the micrometer level.During the heating process,it hinders the molecular movement and makes the material harder.Thus the glass transition temperature is relatively high.展开更多
Silicosis is one of the most serious and prevalent occupational diseases globally,characterized by typical silicotic nodules and fibrosis.Recent studies suggest that the perinodular zone of the lung shares certain cha...Silicosis is one of the most serious and prevalent occupational diseases globally,characterized by typical silicotic nodules and fibrosis.Recent studies suggest that the perinodular zone of the lung shares certain characteristics with the nodules themselves.In this study,a silicotic rat model was established via a single intratracheal in-stillation of a 50 mg/mL silica suspension.Pulmonary anatomical and pathological examinations revealed that silica deposition induced severe alterations in both the nodular and perinodular tissues.Subsequently,pseudo-targeted metabolomics analysis revealed that abnormally elevated ornithine levels were closely associated with the progression of silicosis,from normal to perinodular and finally to nodular tissues.Immunofluorescent stain-ing demonstrated that,in addition to M2 macrophages,silica exposure increased the protein levels of ARG1 in epithelial cells,a finding further confirmed by in vitro experiments using A549 and BEAS-2B cells.Moreover,accumulated ornithine induced epithelial-mesenchymal transition in vitro,increased extracellular matrix expres-sion in NIH 3T3 fibroblasts,and enhanced TGF-β1 levels in RAW264.7 cells.Co-exposure to ornithine and silica significantly induced the aberrant expression of fibrosis-associated proteins compared to silica exposure alone,characterized by increased levels of FN and𝛼-SMA,as well as decreased E-cad expression.These findings sug-gest that silica exposure up-regulates ARG1 in various cells,leading to ornithine accumulation,which in turn accelerates the progression of fibrosis.展开更多
The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them w...The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them was not a typical exhibition hall,but a building shaped like a gleaming stainless-steel cooking pot.展开更多
Crushing waste coral concrete into recycled aggregates to create recycled coral aggregate concrete(RCAC)contributes to sustainable construction development on offshore islands and reefs.To investigate the impact of re...Crushing waste coral concrete into recycled aggregates to create recycled coral aggregate concrete(RCAC)contributes to sustainable construction development on offshore islands and reefs.To investigate the impact of recycled coral aggregate on concrete properties,this study performed a comprehensive analysis of the physical properties of recycled coral aggregate and the basic mechanical properties and microstructure of RCAC.The test results indicate that,compared to coral debris,the crushing index of recycled coral aggregate was reduced by 9.4%,while porosity decreased by 33.5%.Furthermore,RCAC retained the early strength characteristics of coral concrete,with compressive strength and flexural strength exhibiting a notable increase as the water-cement ratio decreased.Under identical conditions,the compressive strength and flexural strength of RCAC were 12.7% and 2.5% higher than coral concrete's,respectively,with porosity correspondingly reduced from 3.13% to 5.11%.This enhancement could be attributed to the new mortar filling the recycled coral aggregate.Scanning electron microscopy(SEM)analysis revealed three distinct interface transition zones within RCAC,with the‘new mortar-old mortar’interface identified as the weakest.The above findings provided a reference for the sustainable use of coral concrete in constructing offshore islands.展开更多
To elucidate the dispersion and explosion characteristics of multi-metal powder and liquid composite fuel formulations,high-energy metal powders(aluminum(Al),boron(B),and magnesium hydride(MgH_(2)))are incorporated in...To elucidate the dispersion and explosion characteristics of multi-metal powder and liquid composite fuel formulations,high-energy metal powders(aluminum(Al),boron(B),and magnesium hydride(MgH_(2)))are incorporated into a liquid fuel primarily composed of diethyl ether(DEE)and isopropyl nitrate(IPN).The explosion characteristics of different solid-liquid fuel-air-explosive(FAE)under unconfined conditions are investigated using a high-speed camera,infrared thermal imaging,and a pressure measurement system.Results demonstrate that high-energy metal powders significantly enhance detonation energy dissipation,with aluminum exhibiting the most pronounced effect.Fuel 5#(45.4 wt%DEE,9.2 wt%IPN,29.5 wt%Al,9.1 wt%B,6.8 wt%MgH_(2))exhibits superior explosion performance,achieving higher values of overpressure,impulse,and thermal radiation damage during the detonation stage compared to other fuels.However,Fuel 5#also displays faster decay rates,attributed to accelerated heat release rates induced by B and MgH_(2)powders.This study reveals that different metal powders in solid-liquid FAE exhibit distinct enhancements in explosion performance,providing critical insights for optimizing composite fuel design.展开更多
This study examined the role of green energy development in mitigating climate change and fostering sustainable development in Central Asia including Kazakhstan,Uzbekistan,Kyrgyzstan,Tajikistan,and Turkmenistan.The re...This study examined the role of green energy development in mitigating climate change and fostering sustainable development in Central Asia including Kazakhstan,Uzbekistan,Kyrgyzstan,Tajikistan,and Turkmenistan.The region has substantial untapped potential in solar energy,wind energy,hydropower energy,as well as biomass and bioenergy,positioning it strategically for renewable energy deployment.The result demonstrated that integrating renewable energy can reduce greenhouse gas emissions,improve air quality,enhance energy security,and support rural development.Case studies from Kazakhstan,Uzbekistan,Kyrgyzstan,and Tajikistan showed measurable environmental and economic benefits.However,the large-scale use of renewable energy still faces numerous barriers,including outdated infrastructure,fragmented regulatory frameworks,limited investment,and shortages of technical expertise.Overcoming these obstacles requires institutional reform,stronger regional cooperation,and increasing engagement from international financial institutions and private investors.Modernizing grids,deploying storage systems,and investing in education,research,and innovation are critical for building human capacity in renewable energy sector.Accelerating the renewable energy transition is essential for Central Asia to meet climate goals,enhance environmental resilience,and ensure long-term socioeconomic development through innovation,investment,and regional collaboration.展开更多
Can the sharing economy contribute to urban sustainability?This study explores this question using the staggered entry of bike-sharing platforms across Chinese cities as a quasi-natural experiment.Drawing on 2015-2017...Can the sharing economy contribute to urban sustainability?This study explores this question using the staggered entry of bike-sharing platforms across Chinese cities as a quasi-natural experiment.Drawing on 2015-2017 city characteristics panel data and monthly CO_(2) emission records,we employ a staggered difference-in-differences(DID)model to assess the impact of bike-sharing on per capita urban CO_(2) emissions.The results show that bike-sharing platforms significantly cut emissions by replacing high-carbon transport and boosting public adoption of shared bikes.This effect is more potent in cities with less stringent environmental enforcement,more advanced digital economies,greater technological innovation,and where two platforms jointly entered.By elucidating the mechanisms underlying bike-sharing’s carbon-reduction potential,this study highlights its role in urban sustainability.It offers policy insights for leveraging shared mobility to reduce city carbon emissions.展开更多
The thermal decomposition characteristic of ammonium perchlorate(AP)represents a critical factor in determining the performance of solid propellants,which has aroused significant interest on the structure and performa...The thermal decomposition characteristic of ammonium perchlorate(AP)represents a critical factor in determining the performance of solid propellants,which has aroused significant interest on the structure and performance improvement of kinds of catalysts.In this study,bimetallic metal-organic frameworks(MOFs),such as CuCo-BTC(BTC=1,3,5-Benzenetricarboxylic acid,H_(3)BTC),CuNi-BTC,and CoNi-BTC,were synthesized by solvothermal(ST)and spray-drying(SD)methods,and then calcined at 400℃for 2 h to form metal oxides.The catalysts as well as their catalytic effects for AP decomposition were characterized by FTIR,XRD,SEM,XPS,TG,DSC,TG-IR,EIS,CV,and LSV.It was found that the rapid coordination of metal ions with ligands during spray drying may lead to catalytic structural defects,promoting the exposure of reactive active sites and increasing the catalytic active region.The results showed that the addition of 2 wt%binary transition metal oxides(BTMOs)as catalysts significantly reduced the high-temperature decomposition(HTD)temperature of AP and enhanced its heat release.Of particular significance is the observation that SD-CoNiO_(x),prepared by spray-drying,reduced the decomposition temperature of AP from 413.26℃(pure AP)to 306℃and enhanced the heat release from 256.79 J/g(pure AP)to 1496.82 J/g,while concomitantly reducing the activation energy by 42%.By analysing the gaseous products during the decomposition of AP+SD-CoNiO_(x)and AP+ST-CoNiO_(x),it was found that SD-CoNiO_(x)could significantly increase the content of high-valent nitrogen oxides during the AP decomposition reaction,which indicates that the BTMOs prepared by spray-drying in the reaction system are more conducive to accelerating the electron transfer in the thermal decomposition process of AP,and can provide a high concentration of reactive oxygen species that oxidize AP to high-valent nitrogen oxide-containing compounds.The present study shows that the structure selectivity of the spray-drying technique influences surfactant molecular arrangement on catalyst surfaces,resulting in their ability to promote higher electron transfer during the catalytic process.Therefore,BTMOs prepared by spray drying method have higher potential for application.展开更多
AIM:To determine whether paeonol(Pae),a naturally occurring phenolic compound,can serve as an effective pharmacological inhibitor of posterior capsular opacification(PCO).METHODS:A rat model of cataract surgery—induc...AIM:To determine whether paeonol(Pae),a naturally occurring phenolic compound,can serve as an effective pharmacological inhibitor of posterior capsular opacification(PCO).METHODS:A rat model of cataract surgery—induced PCO was established,and Pae was administered via anterior chamber injection to evaluate its preventive effect on capsular opacification and fibrotic remodeling.Histological and immunohistochemical analyses were performed to assess epithelial-mesenchymal transition(EMT)—related changes in lens epithelial cells(LECs).Ex vivo lens capsule cultures were employed to examine the expression of Vimentin and Zonula Occludens-1(ZO-1)by immunofluorescence and immunohistochemistry.In the human LEC line SRA01/04,EMT marker expression at both mRNA and protein levels was analyzed following transforming growth factor beta 2(TGF-β2)stimulation,with Pae treatment.Western blotting and immunofluorescence were used to investigate the effect of Pae on TGF-β/Smad signaling and AMP-activated protein kinase(AMPK)activation.Molecular docking was performed to predict Pae–AMPK binding,and rescue experiments with AMPK inhibition were conducted to validate the mechanistic pathway.RESULTS:Pae significantly reduced capsular opacification and fibrotic remodeling in the rat PCO model compared with controls.In LECs,Pae markedly suppressed TGF-β2–induced EMT,evidenced by decreased expression of mesenchymal markers,such as Vimentin,Fibronectin,Collagen 1A1,α-SMA and preserved epithelial junctional protein ZO-1.Mechanistically,Pae was predicted to directly interact with the catalytic pocket of AMPK,which was experimentally confirmed by enhanced AMPK phosphorylation and nuclear translocation(P<0.05).This activation disrupted canonical TGF-β/Smad signaling,leading to suppression of EMT.Rescue experiments using AMPK inhibition abrogated the anti-EMT effect of Pae,further validating the AMPK-dependent mechanism.CONCLUSION:Pae exerts a potent inhibitory effect on PCO formation by blocking EMT of LECs through direct activation of AMPK and subsequent disruption of TGF-β/Smad signaling.展开更多
High-pressure electrides,characterized by the presence of interstitial quasi-atoms(ISQs),possess unique electronic structures and physical properties,such as diverse dimensions of electride states exhibiting different...High-pressure electrides,characterized by the presence of interstitial quasi-atoms(ISQs),possess unique electronic structures and physical properties,such as diverse dimensions of electride states exhibiting different superconductivity,which has attracted significant attention.Here,we report a new electron-deficient type of electride Li_(4)Al and identify its phase transition progress with pressurization,where the internal driving force behind phase transitions,bonding characteristics,and superconducting behaviors have been revealed based on first-principles density functional theory.Through analysis of the bonding properties of electride Li_(4)Al,we demonstrate that the ISQs exhibiting increasingly covalent characteristics between Al ions play a critical role in driving the phase transition.Our electron–phonon coupling calculations indicate that all phases exhibit superconducting behaviors.Importantly,we prove that the ISQs behave as free electrons and demonstrate that the factor governing T_(c) is primarily derived from Li-p-hybridized electronic states with ISQ compositions.These electronic states are scattered by low-frequency phonons arising from mixed vibrations of Li and Al affected by ISQs to enhance electron–phonon coupling.Our study largely expands the research scope of electrides,provides new insight for understanding phase transitions,and elucidates the effects of ISQs on superconducting behavior.展开更多
Oral squamous cell carcinoma(OSCC)is typified by extensive stromal fibrosis and an immunosuppressive microenvironment,both of which impede effective responses to immune checkpoint blockade.In this study,we identify pr...Oral squamous cell carcinoma(OSCC)is typified by extensive stromal fibrosis and an immunosuppressive microenvironment,both of which impede effective responses to immune checkpoint blockade.In this study,we identify prolyl 3-hydroxylase family member 4(P3H4)as a critical mediator of extracellular matrix(ECM)remodeling,epithelial-mesenchymal transition(EMT),and the exclusion of cytotoxic CD8+T lymphocytes.Elevated P3H4 expression correlates with unfavorable clinical outcomes and resistance to immunotherapy.Genetic ablation of P3H4 significantly attenuates tumor progression and promotes CD8^(+)T cell infiltration.To pharmacologically target P3H4,we engineered a liposomal formulation of 1,4-dihydrophenanthroline-2,5-dicarboxylic acid(1,4-DPCA),a small-molecule prolyl hydroxylase inhibitor.This nanomedicine,designated Lipo-1,4-DPCA,effectively downregulates P3H4 expression,mitigates tumor-associated fibrosis,reprograms the immune microenvironment,and elicits robust anti-tumor responses in vivo.Collectively,our findings establish P3H4 as a promising therapeutic target and highlight Lipo-1,4-DPCA as a dualfunctional nanotherapeutic candidate capable of enhancing the efficacy of immunotherapy in OSCC.展开更多
Rapid regional population shifts and spatial polarization have heightened pressure on cultivated land—a critical resource demanding urgent attention amid ongoing urban-rural transition.This study selects Jiangsu prov...Rapid regional population shifts and spatial polarization have heightened pressure on cultivated land—a critical resource demanding urgent attention amid ongoing urban-rural transition.This study selects Jiangsu province,a national leader in both economic and agricultural development,as a case area to construct a multidimensional framework for assessing the recessive morphological characteristics of multifunctional cultivated land use.We examine temporal dynamics,spatial heterogeneity,and propose an integrated zoning strategy based on empirical analysis.The results reveal that:(1)The recessive morphology index shows a consistent upward trend,with structural breaks in 2007 and 2013,and a spatial shift from“higher in the east and lower in the west”to“higher in the south and lower in the north.”(2)Coordination among sub-dimensions of the index has steadily improved.(3)The index is expected to continue rising in the next decade,though at a slower pace.(4)To promote coordinated multidimensional land-use development,we recommend a policy framework that reinforces existing strengths,addresses weaknesses,and adapts zoning schemes to current spatial conditions.This research offers new insights into multifunctional cultivated land systems and underscores their role in enhancing human well-being,securing food supply,and supporting sustainable urban-rural integration.展开更多
文摘Located in northwest Beijing, Zhongguancun is often referred to as China＇s very own Silicon Valley. However, the current reputation of this neighborhood as a hub of advanced Chinese technology contrasts sharply with its traditional cliched image. Only a few years ago, this place was one of the largest wholesale markets for electronic products. The way Zhongg-uancun was able to transi tion toward innovation by attracting startups continues to surprise visitors, whether Chinese or foreigners.
基金supported by the National Natural Science Foundation of China(Grant Nos.42075053 and 41975128)。
文摘Based on the Regional Specialized Meteorological Center(RSMC)Tokyo-Typhoon Center best-track data and the NCEP-NCAR reanalysis dataset,extratropical transitioning(ET)tropical cyclones(ETCs)over the western North Pacific(WNP)during 1951–2021 are classified into six clusters using the fuzzy c-means clustering method(FCM)according to their track patterns.The characteristics of the six hard-clustered ETCs with the highest membership coefficient are shown.Most tropical cyclones(TCs)that were assigned to clusters C2,C5,and C6 made landfall over eastern Asian countries,which severely threatened these regions.Among landfalling TCs,93.2%completed their ET after landfall,whereas 39.8%of ETCs completed their transition within one day.The frequency of ETCs over the WNP has decreased in the past four decades,wherein cluster C5 demonstrated a significant decrease on both interannual and interdecadal timescales with the expansion and intensification of the western Pacific subtropical high(WPSH).This large-scale circulation pattern is favorable for C2 and causes it to become the dominant track pattern,owning to it containing the largest number of intensifying ETCs among the six clusters,a number that has increased insignificantly over the past four decades.The surface roughness variation and three-dimensional background circulation led to C5 containing the maximum number of landfalling TCs and a minimum number of intensifying ETCs.Our results will facilitate a better understanding of the spatiotemporal distributions of ET events and associated environment background fields,which will benefit the effective monitoring of these events over the WNP.
文摘This paper presents the views of 623 informal and formal small,medium,and micro enterprises(SMMEs)operating in the Gauteng Province of South Africa.The objective of the study was to identify challenges and benefits that are experienced by SMMEs during and after the registration process leading to the transition from informal to formal business,the level of awareness by the SMMEs of the registration information,and the procedures in addition to the potential factors that inspire or discourage informal and prospective business registration.The reason for including both informal and formal SMMEs in the survey was to compare the perceptions of these groups of businesses regarding the triggers and/or barriers to register as a formal business.The results show that for both informal and formal businesses,the liability of paying taxes was a major challenge while improved workers’health and safety accrued as a major benefit.Own research emerged as the main source of access to business registration information and procedure.The costs involved in registration were highlighted as one of the major factors discouraging registration but the prospects of expanding the customer base and the ability to achieve a higher turnover as some of the main inspiring factors.The study recommends the development of policies that provide an enabling environment for sustainable enterprises but also to implement measures that improve productivity through access to finance,skills,infrastructure,markets,and technology transfers.
文摘Original reference:iEnergy,3(1):46-58,2024 Grid-tie voltage source converters(VSCs)can operate in three distinct modes:AC-dominant,DC-dominant,and balanced,depending on the placement of the stiff voltage sources,as shown in Figure 1.The distinct operation modes of VSCs typically require different synchronization control techniques.For instance,the grid-following(GFL)control,which utilizes a phase-locked loop to track the AC grid phase and frequency,can be employed for VSCs operating in the AC-dominant mode and the balanced mode.On the other hand,the grid-forming(GFM)control is uti-lized for VSCs operating in the DC-dominant mode and the bal-anced mode.Therefore,neither GFM control nor GFL control can serve as a universal synchronization control technique for VSCs to operate in all of the three modes.While the combination of the GFL VSCs and the GFM VSCs can handle applications that require the VSCs to operate in all of the three modes,effectively accommodating and coordinating the heterogeneous GFL and GFM VSCs remains challenging for power systems.
文摘Original reference:iEnergy,2(2):93-99,2023 Droplet-based triboelectric nanogenerator(D-TENG)using liquid-solid contact electrification has been widely studied for harvesting raindrop energy and ocean energy due to its unique ability to effectively reduce friction between solids and improve durability.In 2020,a new-generation D-TENG with a“transistor-like”struc-ture was proposed,which first achieved ultra-high instantaneous power output(50 W/m2).Subsequently,D-TENG has been rapidly developed and is widely used in ocean wave energy power gener-ation and liquid-solid triboelectric power generation.Currently,although we have excellent D-TENGs to harvest energy from a single water droplet,but if multiple D-TENGs are simply connected in parallel for a large area usage,the output power of the whole power generation module will drop significantly due to the mutual influence between different individual generation units,which severely limits their applications in practice.Therefore,finding a reasonable topology to relieve the inherent constraints of D-TENGs is of great significance for realizing the large-scale rain-drop energy harvesting.
基金the Ministry of Science and Technology of China(Nos.2021YFA1102000,2021YFC2700300,2019YFA0110000,and 2018YFA0108900)the National Natural Science Foundation of China(NSFC)(Nos.31721003,32022024,32270850,32100633,31871486,32070652,and 81630035)the Science and Technology Commission of Shanghai Municipality(Nos.19JC1415300 and 21JC1405500).
文摘Human pluripotent stem cells provide an inexhaustible model to study human embryogenesis in vitro.Recent studies have provided diverse models to generate human blastoids by self-organization of different pluripotent stem cells or somatic reprogramming intermediates.However,whether blastoids can be generated from other cell types or whether they can recapitulate postimplantation development in vitro is unknown.Here,we develop a strategy to generate human blastoids from heterogeneous intermediates with epiblast,trophectoderm,and primitive endoderm signatures of the primed-to-naïve conversion process,which resemble natural blastocysts in morphological architecture,composition of cell lineages,transcriptome,and lineage differentiation potential.In addition,these blastoids reflect many features of human peri-implantation and pregastrulation development when further cultured in an in vitro 3D culture system.In summary,our study provides an alternative strategy to generate human blastoids and offers insights into human early embryogenesis by modeling peri-and postimplantation development in vitro.
文摘Over the next 20 years,China's urban rail transit(hereinafter referred to as'urban rail')will face large-scalerenovation of existing line facilities and equipment,with more than 1000 km of renovated lines to be added eachyear.In 2024,the China Association of Metros issued the Guiding Opinions on the Renovation of Existing UrbanRail Transit Lines in China,providing guiding opinions on norms,standards,and implementation approaches forthe renovation of existing lines in the coming period.In the practical work of renovating existing urban rail lines,it is necessary to continuously explore and refine relevant theoretical methods in line with industry developmenttrends and urban development requirements.The following are the author's recent reflections on theoreticalinnovation in this field.
基金Supported by the National Natural Science Foundation of China(No.52273056)the Science and Technology Development Program of Jilin Province,China(No.YDZJ202501ZYTS305)。
文摘Electrochemical water splitting represents a sustainable technology for hydrogen(H_(2))production.However,its large-scale implementation is hindered by the high overpotentials required for both the cathodic hydrogen evolution reaction(HER)and the anodic oxygen evolution reaction(OER).Transition metal-based catalysts have garnered significant research interest as promising alternatives to noble-metal catalysts,owing to their low cost,tunable composition,and noble-metal-like catalytic activity.Nevertheless,systematic reviews on their application as bifunctional catalysts for overall water splitting(OWS)are still limited.This review comprehensively outlines the principal categories of bifunctional transition metal electrocatalysts derived from electrospun nanofibers(NFs),including metals,oxides,phosphides,sulfides,and carbides.Key strategies for enhancing their catalytic performance are systematically summarized,such as heterointerface engineering,heteroatom doping,metal-nonmetal-metal bridging architectures,and single-atom site design.Finally,current challenges and future research directions are discussed,aiming to provide insightful perspectives for the rational design of high-performance electrocatalysts for OWS.
基金Funded by National Natural Science Foundation of China(No.52472033)。
文摘Dynamic thermal mechanical analysis was used to evaluate the viscoelasticity of asphalt.The parameters included the energy storage modulus(E),the loss modulus(E'),and the loss tangent(tanδ).The impact of three kinds of particles containing CaCO_(3)with different size and structure on the mechanical properties was also measured.The addition of limestone increases the glass transition temperature,while nanoCaCO_(3)@SiO_(2)decreases the glass transition temperature.Nano-CaCO_(3)has a negligible effect on the glass transition temperature.The particle size of the limestone is 0.075 mm,which is a material at the micrometer level.During the heating process,it hinders the molecular movement and makes the material harder.Thus the glass transition temperature is relatively high.
基金supported by the National Natural Science Foundation of China(No.81973466)the National Administration of Traditional Chinese Medicine Youth Qihuang Scholars Support Project,and the Program of Graduate Innovation Research in Shanxi Province(No.2023KY019).
文摘Silicosis is one of the most serious and prevalent occupational diseases globally,characterized by typical silicotic nodules and fibrosis.Recent studies suggest that the perinodular zone of the lung shares certain characteristics with the nodules themselves.In this study,a silicotic rat model was established via a single intratracheal in-stillation of a 50 mg/mL silica suspension.Pulmonary anatomical and pathological examinations revealed that silica deposition induced severe alterations in both the nodular and perinodular tissues.Subsequently,pseudo-targeted metabolomics analysis revealed that abnormally elevated ornithine levels were closely associated with the progression of silicosis,from normal to perinodular and finally to nodular tissues.Immunofluorescent stain-ing demonstrated that,in addition to M2 macrophages,silica exposure increased the protein levels of ARG1 in epithelial cells,a finding further confirmed by in vitro experiments using A549 and BEAS-2B cells.Moreover,accumulated ornithine induced epithelial-mesenchymal transition in vitro,increased extracellular matrix expres-sion in NIH 3T3 fibroblasts,and enhanced TGF-β1 levels in RAW264.7 cells.Co-exposure to ornithine and silica significantly induced the aberrant expression of fibrosis-associated proteins compared to silica exposure alone,characterized by increased levels of FN and𝛼-SMA,as well as decreased E-cad expression.These findings sug-gest that silica exposure up-regulates ARG1 in various cells,leading to ornithine accumulation,which in turn accelerates the progression of fibrosis.
文摘The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them was not a typical exhibition hall,but a building shaped like a gleaming stainless-steel cooking pot.
基金Funded by Natural Science Foundation of Guangxi(No.2025GXNSFBA069565)Guangxi Science and Technology Program(No.AD25069101)Guangxi Bagui Scholars Fund。
文摘Crushing waste coral concrete into recycled aggregates to create recycled coral aggregate concrete(RCAC)contributes to sustainable construction development on offshore islands and reefs.To investigate the impact of recycled coral aggregate on concrete properties,this study performed a comprehensive analysis of the physical properties of recycled coral aggregate and the basic mechanical properties and microstructure of RCAC.The test results indicate that,compared to coral debris,the crushing index of recycled coral aggregate was reduced by 9.4%,while porosity decreased by 33.5%.Furthermore,RCAC retained the early strength characteristics of coral concrete,with compressive strength and flexural strength exhibiting a notable increase as the water-cement ratio decreased.Under identical conditions,the compressive strength and flexural strength of RCAC were 12.7% and 2.5% higher than coral concrete's,respectively,with porosity correspondingly reduced from 3.13% to 5.11%.This enhancement could be attributed to the new mortar filling the recycled coral aggregate.Scanning electron microscopy(SEM)analysis revealed three distinct interface transition zones within RCAC,with the‘new mortar-old mortar’interface identified as the weakest.The above findings provided a reference for the sustainable use of coral concrete in constructing offshore islands.
基金supported by the National Natural Science Foundation of China(Grant No.12402432)Natural Science Foundation of Jiangsu Province of China(Grant No.BK20230936)Graduate Education and Teaching Reform Project of Nanjing University of Science and Technology(Grant No.KT2024_C14)。
文摘To elucidate the dispersion and explosion characteristics of multi-metal powder and liquid composite fuel formulations,high-energy metal powders(aluminum(Al),boron(B),and magnesium hydride(MgH_(2)))are incorporated into a liquid fuel primarily composed of diethyl ether(DEE)and isopropyl nitrate(IPN).The explosion characteristics of different solid-liquid fuel-air-explosive(FAE)under unconfined conditions are investigated using a high-speed camera,infrared thermal imaging,and a pressure measurement system.Results demonstrate that high-energy metal powders significantly enhance detonation energy dissipation,with aluminum exhibiting the most pronounced effect.Fuel 5#(45.4 wt%DEE,9.2 wt%IPN,29.5 wt%Al,9.1 wt%B,6.8 wt%MgH_(2))exhibits superior explosion performance,achieving higher values of overpressure,impulse,and thermal radiation damage during the detonation stage compared to other fuels.However,Fuel 5#also displays faster decay rates,attributed to accelerated heat release rates induced by B and MgH_(2)powders.This study reveals that different metal powders in solid-liquid FAE exhibit distinct enhancements in explosion performance,providing critical insights for optimizing composite fuel design.
文摘This study examined the role of green energy development in mitigating climate change and fostering sustainable development in Central Asia including Kazakhstan,Uzbekistan,Kyrgyzstan,Tajikistan,and Turkmenistan.The region has substantial untapped potential in solar energy,wind energy,hydropower energy,as well as biomass and bioenergy,positioning it strategically for renewable energy deployment.The result demonstrated that integrating renewable energy can reduce greenhouse gas emissions,improve air quality,enhance energy security,and support rural development.Case studies from Kazakhstan,Uzbekistan,Kyrgyzstan,and Tajikistan showed measurable environmental and economic benefits.However,the large-scale use of renewable energy still faces numerous barriers,including outdated infrastructure,fragmented regulatory frameworks,limited investment,and shortages of technical expertise.Overcoming these obstacles requires institutional reform,stronger regional cooperation,and increasing engagement from international financial institutions and private investors.Modernizing grids,deploying storage systems,and investing in education,research,and innovation are critical for building human capacity in renewable energy sector.Accelerating the renewable energy transition is essential for Central Asia to meet climate goals,enhance environmental resilience,and ensure long-term socioeconomic development through innovation,investment,and regional collaboration.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant No.72372048)the“Young Top-Notch Talent”Cultivation Program of Hubei Province.
文摘Can the sharing economy contribute to urban sustainability?This study explores this question using the staggered entry of bike-sharing platforms across Chinese cities as a quasi-natural experiment.Drawing on 2015-2017 city characteristics panel data and monthly CO_(2) emission records,we employ a staggered difference-in-differences(DID)model to assess the impact of bike-sharing on per capita urban CO_(2) emissions.The results show that bike-sharing platforms significantly cut emissions by replacing high-carbon transport and boosting public adoption of shared bikes.This effect is more potent in cities with less stringent environmental enforcement,more advanced digital economies,greater technological innovation,and where two platforms jointly entered.By elucidating the mechanisms underlying bike-sharing’s carbon-reduction potential,this study highlights its role in urban sustainability.It offers policy insights for leveraging shared mobility to reduce city carbon emissions.
基金supported by the National Natural ScienceFoundation of China(Grant No.52203332)。
文摘The thermal decomposition characteristic of ammonium perchlorate(AP)represents a critical factor in determining the performance of solid propellants,which has aroused significant interest on the structure and performance improvement of kinds of catalysts.In this study,bimetallic metal-organic frameworks(MOFs),such as CuCo-BTC(BTC=1,3,5-Benzenetricarboxylic acid,H_(3)BTC),CuNi-BTC,and CoNi-BTC,were synthesized by solvothermal(ST)and spray-drying(SD)methods,and then calcined at 400℃for 2 h to form metal oxides.The catalysts as well as their catalytic effects for AP decomposition were characterized by FTIR,XRD,SEM,XPS,TG,DSC,TG-IR,EIS,CV,and LSV.It was found that the rapid coordination of metal ions with ligands during spray drying may lead to catalytic structural defects,promoting the exposure of reactive active sites and increasing the catalytic active region.The results showed that the addition of 2 wt%binary transition metal oxides(BTMOs)as catalysts significantly reduced the high-temperature decomposition(HTD)temperature of AP and enhanced its heat release.Of particular significance is the observation that SD-CoNiO_(x),prepared by spray-drying,reduced the decomposition temperature of AP from 413.26℃(pure AP)to 306℃and enhanced the heat release from 256.79 J/g(pure AP)to 1496.82 J/g,while concomitantly reducing the activation energy by 42%.By analysing the gaseous products during the decomposition of AP+SD-CoNiO_(x)and AP+ST-CoNiO_(x),it was found that SD-CoNiO_(x)could significantly increase the content of high-valent nitrogen oxides during the AP decomposition reaction,which indicates that the BTMOs prepared by spray-drying in the reaction system are more conducive to accelerating the electron transfer in the thermal decomposition process of AP,and can provide a high concentration of reactive oxygen species that oxidize AP to high-valent nitrogen oxide-containing compounds.The present study shows that the structure selectivity of the spray-drying technique influences surfactant molecular arrangement on catalyst surfaces,resulting in their ability to promote higher electron transfer during the catalytic process.Therefore,BTMOs prepared by spray drying method have higher potential for application.
基金Supported by the Projects of Medical and Health Technology Development Program in Shandong Province(No.202107021009)Shandong Provincial Traditional Chinese Medicine Science and Technology Project(No.M-2023118).
文摘AIM:To determine whether paeonol(Pae),a naturally occurring phenolic compound,can serve as an effective pharmacological inhibitor of posterior capsular opacification(PCO).METHODS:A rat model of cataract surgery—induced PCO was established,and Pae was administered via anterior chamber injection to evaluate its preventive effect on capsular opacification and fibrotic remodeling.Histological and immunohistochemical analyses were performed to assess epithelial-mesenchymal transition(EMT)—related changes in lens epithelial cells(LECs).Ex vivo lens capsule cultures were employed to examine the expression of Vimentin and Zonula Occludens-1(ZO-1)by immunofluorescence and immunohistochemistry.In the human LEC line SRA01/04,EMT marker expression at both mRNA and protein levels was analyzed following transforming growth factor beta 2(TGF-β2)stimulation,with Pae treatment.Western blotting and immunofluorescence were used to investigate the effect of Pae on TGF-β/Smad signaling and AMP-activated protein kinase(AMPK)activation.Molecular docking was performed to predict Pae–AMPK binding,and rescue experiments with AMPK inhibition were conducted to validate the mechanistic pathway.RESULTS:Pae significantly reduced capsular opacification and fibrotic remodeling in the rat PCO model compared with controls.In LECs,Pae markedly suppressed TGF-β2–induced EMT,evidenced by decreased expression of mesenchymal markers,such as Vimentin,Fibronectin,Collagen 1A1,α-SMA and preserved epithelial junctional protein ZO-1.Mechanistically,Pae was predicted to directly interact with the catalytic pocket of AMPK,which was experimentally confirmed by enhanced AMPK phosphorylation and nuclear translocation(P<0.05).This activation disrupted canonical TGF-β/Smad signaling,leading to suppression of EMT.Rescue experiments using AMPK inhibition abrogated the anti-EMT effect of Pae,further validating the AMPK-dependent mechanism.CONCLUSION:Pae exerts a potent inhibitory effect on PCO formation by blocking EMT of LECs through direct activation of AMPK and subsequent disruption of TGF-β/Smad signaling.
基金supported by the National Key Research and Development Program of China (Grant Nos.2023YFA1406200 and 2022YFA-1405500)the National Natural Science Foundation of China (Grant Nos.12304021 and 52072188)+3 种基金Zhejiang Provincial Natural Science Foundation of China (Grant Nos.LQ23A040004 and MS26A040028)Natural Science Foundation of Ningbo (Grant Nos.2022J091 and ZX2025001430)the Program for Science and Technology Innovation Team in Zhejiang (Grant No.2021R01004)the Program for Changjiang Scholars and Innovative Research Team in University (Grant No.IRT_15R23)。
文摘High-pressure electrides,characterized by the presence of interstitial quasi-atoms(ISQs),possess unique electronic structures and physical properties,such as diverse dimensions of electride states exhibiting different superconductivity,which has attracted significant attention.Here,we report a new electron-deficient type of electride Li_(4)Al and identify its phase transition progress with pressurization,where the internal driving force behind phase transitions,bonding characteristics,and superconducting behaviors have been revealed based on first-principles density functional theory.Through analysis of the bonding properties of electride Li_(4)Al,we demonstrate that the ISQs exhibiting increasingly covalent characteristics between Al ions play a critical role in driving the phase transition.Our electron–phonon coupling calculations indicate that all phases exhibit superconducting behaviors.Importantly,we prove that the ISQs behave as free electrons and demonstrate that the factor governing T_(c) is primarily derived from Li-p-hybridized electronic states with ISQ compositions.These electronic states are scattered by low-frequency phonons arising from mixed vibrations of Li and Al affected by ISQs to enhance electron–phonon coupling.Our study largely expands the research scope of electrides,provides new insight for understanding phase transitions,and elucidates the effects of ISQs on superconducting behavior.
基金supported by grants from the National Natural Science Foundation of China(Nos.82501207,81700993,52403312,and 82571151)Postdoctoral Fellowship Program of CPSF(No.GZC20251219)+1 种基金the Beijing Nova Program(No.20250484855)the Beijing Natural Science Foundation(No.L252168).
文摘Oral squamous cell carcinoma(OSCC)is typified by extensive stromal fibrosis and an immunosuppressive microenvironment,both of which impede effective responses to immune checkpoint blockade.In this study,we identify prolyl 3-hydroxylase family member 4(P3H4)as a critical mediator of extracellular matrix(ECM)remodeling,epithelial-mesenchymal transition(EMT),and the exclusion of cytotoxic CD8+T lymphocytes.Elevated P3H4 expression correlates with unfavorable clinical outcomes and resistance to immunotherapy.Genetic ablation of P3H4 significantly attenuates tumor progression and promotes CD8^(+)T cell infiltration.To pharmacologically target P3H4,we engineered a liposomal formulation of 1,4-dihydrophenanthroline-2,5-dicarboxylic acid(1,4-DPCA),a small-molecule prolyl hydroxylase inhibitor.This nanomedicine,designated Lipo-1,4-DPCA,effectively downregulates P3H4 expression,mitigates tumor-associated fibrosis,reprograms the immune microenvironment,and elicits robust anti-tumor responses in vivo.Collectively,our findings establish P3H4 as a promising therapeutic target and highlight Lipo-1,4-DPCA as a dualfunctional nanotherapeutic candidate capable of enhancing the efficacy of immunotherapy in OSCC.
基金National Natural Science Foundation of China,No.42101252。
文摘Rapid regional population shifts and spatial polarization have heightened pressure on cultivated land—a critical resource demanding urgent attention amid ongoing urban-rural transition.This study selects Jiangsu province,a national leader in both economic and agricultural development,as a case area to construct a multidimensional framework for assessing the recessive morphological characteristics of multifunctional cultivated land use.We examine temporal dynamics,spatial heterogeneity,and propose an integrated zoning strategy based on empirical analysis.The results reveal that:(1)The recessive morphology index shows a consistent upward trend,with structural breaks in 2007 and 2013,and a spatial shift from“higher in the east and lower in the west”to“higher in the south and lower in the north.”(2)Coordination among sub-dimensions of the index has steadily improved.(3)The index is expected to continue rising in the next decade,though at a slower pace.(4)To promote coordinated multidimensional land-use development,we recommend a policy framework that reinforces existing strengths,addresses weaknesses,and adapts zoning schemes to current spatial conditions.This research offers new insights into multifunctional cultivated land systems and underscores their role in enhancing human well-being,securing food supply,and supporting sustainable urban-rural integration.
