Essentially clearing the structure-activity relationship between iron carbide catalysts involving multiple active centers to understand the reaction mechanism of CO hydrogenation conversion process is still a great ch...Essentially clearing the structure-activity relationship between iron carbide catalysts involving multiple active centers to understand the reaction mechanism of CO hydrogenation conversion process is still a great challenge.Here,two main micro-environment factors,namely electronic properties and geometrical effects were found to have an integrated effect on the mechanism of CO hydrogenation conversion,involving active sites on multiple crystal phases.The Bader charge of the surface Fe atoms on the active sites had a guiding effect on the CO activation pathway,while the spatial configuration of the active sites greatly affected the energy barriers of CO activation.Although the defective surfaces were more conducive to CO activation,the defective sites were not the only sites to dissociate CO,as CO always tended to dissociate in a wider area.This synergistic effect of the micro-environment also occurred during the CO conversion process.Surface C atoms on relatively flat configurations were more likely to form methane,while the electronic properties of the active sites could effectively describe the C-C coupling process,as well as distinguish the coupling mechanisms.展开更多
Background:Recurrent implantation failure(RIF)is a difficult problem with a multifaceted cause.Recent studies have demonstrated that stimulator of interferon genes-induced immune-related genes(STIRGs)are associated wi...Background:Recurrent implantation failure(RIF)is a difficult problem with a multifaceted cause.Recent studies have demonstrated that stimulator of interferon genes-induced immune-related genes(STIRGs)are associated with immune disorders that may affect the endometrial immune micro-environment.However,the effect of STRIGs on RIF remains unknown.Methods:Training(GSE111974)and validation(GSE106602)cohorts were acquired from the Gene Expression Omnibus database.STIRGs were extracted from the Molecular Signatures Database and relevant studies.Consensus clustering analysis was used to identify RIF molecular subtypes.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment and immune infiltration analyses were performed between RIF subtypes.Drug-related potential therapeutic target genes were discovered.Results:Two distinct molecular subtypes were discovered in both the training and validation groups according to STIRGs.In subtype C2,there was a notable decrease in the presence of different types of immune cells,such as natural killer cells and macrophages.Furthermore,the examination of Gene Ontology and Kyoto Encyclopedia of Genes and Genomes indicated a decrease in numerous immune-related biological processes within subtype C2.Finally,nine hub genes(CXCR4,POU5F1,PPARG,TLR2,EGFR,CSF1,BCL2A1,BTK,and SRGN)were identified as potential therapeutic targets for RIF.Conclusion:Based on STIRGs,we identified a new molecular subtype with significantly reduced immune infiltration in RIF.Nine genes might be potential therapeutic targets for RIF.展开更多
Surface functionalization of Cu-based catalysts has demonstrated promising potential for enhancing the electrochemical CO_(2)reduction reaction(CO_(2)RR)toward multi-carbon(C2+)products,primarily by suppressing the pa...Surface functionalization of Cu-based catalysts has demonstrated promising potential for enhancing the electrochemical CO_(2)reduction reaction(CO_(2)RR)toward multi-carbon(C2+)products,primarily by suppressing the parasitic hydrogen evolution reaction and facilitating a localized CO_(2)/CO concentration at the electrode.Building upon this approach,we developed surface-functionalized catalysts with exceptional activity and selectivity for electrocatalytic CO_(2)RR to C_(2+)in a neutral electrolyte.Employing CuO nanoparticles coated with hexaethynylbenzene organic molecules(HEB-CuO NPs),a remarkable C_(2+)Faradaic efficiency of nearly 90%was achieved at an unprecedented current density of 300 mA cm^(-2),and a high FE(>80%)was maintained at a wide range of current densities(100-600 mA cm^(-2))in neutral environments using a flow cell.Furthermore,in a membrane electrode assembly(MEA)electrolyzer,86.14%FEC2+was achieved at a partial current density of 387.6 mA cm^(-2)while maintaining continuous operation for over 50 h at a current density of 200 mA cm^(-2).In-situ spectroscopy studies and molecular dynamics simulations reveal that reducing the coverage of coordinated K⋅H2O water increased the probability of intermediate reactants(CO)interacting with the surface,thereby promoting efficient C-C coupling and enhancing the yield of C_(2+)products.This advancement offers significant potential for optimizing local micro-environments for sustainable and highly efficient C_(2+)production.展开更多
The irrigation method used in winter wheat fields affects micro-environment factors, such as relative humidity(RH) within canopy, soil temperature, topsoil bulk density, soil matric potential, and soil nutrients, an...The irrigation method used in winter wheat fields affects micro-environment factors, such as relative humidity(RH) within canopy, soil temperature, topsoil bulk density, soil matric potential, and soil nutrients, and these changes may affect plant root growth.An experiment was carried out to explore the effects of irrigation method on micro-environments and root distribution in a winter wheat field in the 2007–2008 and 2008–2009 growing seasons.The results showed that border irrigation(BI), sprinkler irrigation(SI), and surface drip irrigation(SDI) had no significant effects on soil temperature.Topsoil bulk density, RH within the canopy, soil available N distribution, and soil matric potential were significantly affected by the three treatments.The change in soil matric potential was the key reason for the altered root profile distribution patterns.Additionally, more fine roots were produced in the BI treatment when soil water content was low and topsoil bulk density was high.Root growth was most stimulated in the top soil layers and inhibited in the deep layers in the SDI treatment, followed by SI and BI, which was due to the different water application frequencies.As a result, the root profile distribution differed, depending on the irrigation method used.The root distribution pattern changes could be described by the power level variation in the exponential function.A good knowledge of root distribution patterns is important when attempting to model water and nutrient movements and when studying soil-plant interactions.展开更多
The integrated lipopeptide(RVA)/gene complexes are fabricated with bi-directional regulation on tumor cells and micro-environment.After self-assembling and target coating modification,the poly(γ-glutamic acid)(γ-PGA...The integrated lipopeptide(RVA)/gene complexes are fabricated with bi-directional regulation on tumor cells and micro-environment.After self-assembling and target coating modification,the poly(γ-glutamic acid)(γ-PGA)/RVA nano-vectors can sequentially respond to pH&redox stimuli,and guarantee efficient therapeutic gene delivery and control release of all-trans retinoic acid.The design provides a facile but promising strategy to treat refractory cancers.展开更多
A three-dimensional (3D) mathematical model of tumour growth at the avascular phase and vessel remodelling in host tissues is proposed with emphasis on the study of the interactions of tumour growth and hypoxic micr...A three-dimensional (3D) mathematical model of tumour growth at the avascular phase and vessel remodelling in host tissues is proposed with emphasis on the study of the interactions of tumour growth and hypoxic micro-environment in host tissues. The hybrid based model includes the continuum part, such as the distributions of oxygen and vascular endothelial growth factors (VEGFs), and the discrete part of tumour cells (TCs) and blood vessel networks. The simulation shows the dynamic process of avascular tumour growth from a fewinitial cells to an equilibrium state with varied vessel networks. After a phase of rapidly increasing numbers of the TCs, more and more host vessels collapse due to the stress caused by the growing tumour. In addition, the consumption of oxygen expands with the enlarged tumour region. The study also discusses the effects of certain factors on tumour growth, including the density and configuration of pre- existing vessel networks and the blood oxygen content. The model enables us to examine the relationship between early tumour growth and hypoxic micro-environment in host tissues, which can be useful for further applications, such as tumour metastasis and the initialization of tumour angiogenesis.展开更多
Three kinds of packaging bags composited with barrier film and moisture absorbents were designed in order to find out how to create an internal micro-environment with low O2content and relative humidity( RH). Peanuts ...Three kinds of packaging bags composited with barrier film and moisture absorbents were designed in order to find out how to create an internal micro-environment with low O2content and relative humidity( RH). Peanuts with different moisture contents were filled into packaging bags and stored in an environmental chamber for a certain period of time. An RH recorder was sealed in each bag and the RH inside the bag was recorded. The moisture contents of peanuts before and after storage were measured as well.It is found that peanuts with moisture content of 13% can reduce O2content inside the bag by the aerobic respiration,achieving the self modified atmosphere packaging( MAP) effect. A microenvironment with lower RH can be created by using super-absorbent fiber( SAF) or mineral bag as the moisture absorbent. The moisture contents of peanuts stored in the bags with SAF and mineral bag as moisture absorbent decreased from 13% to 10. 5%and 11. 3%,respectively. SAF is a promising material of packaging bags composited with barrier film,in which a low RH and high CO2content can be created.展开更多
The wax palm (Ceroxylon echinulatum) and palm heart (Prestoea acuminata) are key elements in Andean natural forests. This ecosystem is threatened by deforestation and habitat degradation, thus, it is vital to explore ...The wax palm (Ceroxylon echinulatum) and palm heart (Prestoea acuminata) are key elements in Andean natural forests. This ecosystem is threatened by deforestation and habitat degradation, thus, it is vital to explore the impact of anthropogenic activities on the ecological structure and preferences of these species in order to develop proper conservation strategies. Fifty-seven 400 m2 plots were established in two forest areas, a disturbed forest (n = 30 plots) and an undisturbed forest (n = 27 plots) in the Ecuadorean Andes. Nine micro-environmental variables and the number of individuals of C. echinulatum and P. acuminata in five size classes were recorded in each plot. Logistic regression models helped identify environmental variables that influence the establishment of the species. Results showed that different micro-environmental variables determined the presence of different size classes. Both species were benefitted by the environmental conditions of the disturbed forest. Light availability was important for the establishment of both species, especially for the canopy species (C. echinulatum). This palm was negatively affected by the variable “fallen wood”, while P. acuminata was negatively affected mainly by the steepness of the terrain. The environmental variables for the successful establishment of the studied species that were identified by this study provide clues for the sustainable management of C. echinulatum and P. acuminata in Andean forests.展开更多
Micro-environmental restriction effects to yeast cell growth obtained within Ca-alginate microbeads are considered. It is complex phenomenon influenced by: (1) relaxation of expanded polymer network around the cellula...Micro-environmental restriction effects to yeast cell growth obtained within Ca-alginate microbeads are considered. It is complex phenomenon influenced by: (1) relaxation of expanded polymer network around the cellular clusters, (2) forces generated by cell growth inside the beads and (3) interactions between solvent, network parts and cells. The resulting effects are measured experimentally by estimating volume of microbeads and yeast cell concentration as function of time of cultivation. Comparative analysis of dynamics of cell growth and increase of microbead volume through four regimes indicates that reversible and irreversible local structural changes of Ca-alginate hydrogel induces micro-environmental restrictions to cell growth. The mechanism of restrictions includes both mechanical and electrostatic effects.展开更多
A small English class can be called as a micro-environment for English study. In this small micro-environment, the relationship between teachers and students is subtle. How to achieve the good interaction and create a...A small English class can be called as a micro-environment for English study. In this small micro-environment, the relationship between teachers and students is subtle. How to achieve the good interaction and create a good micro-environment in English class between teachers and students is very important for developing students' learning ability. This thesis is based on Rogers' humanistic teaching theory, which uses questionnaires, inteview and comparative analysis to analyze the current situation of micro-environment in college English learning. It discusses the construction of micro-environment in college English learning based on Rogers' humanistic teaching theory and the ways to construct it from software conditions (roles of teachers and students, relationship between teachers and students, the classroom atmosphere) and hardware conditions(teaching resources, a classroom).展开更多
Essentially developing and regulating the unique electronic property of iron carbide catalysts involving multi-metal promoters to understand the structure–activity relationship of the CO_(2)activation process is stil...Essentially developing and regulating the unique electronic property of iron carbide catalysts involving multi-metal promoters to understand the structure–activity relationship of the CO_(2)activation process is still a great challenge.Here,metals and transition metals were introduced as strategies for electronic structure regulation to theoretically understand the underlying nature of CO_(2)adsorption and activation behaviors over Fe_(3)C catalysts.The distinctive micro-environment on the Fe_(3)C surface made it more conducive to CO_(2)adsorption and activation compared to other Fe-based catalysts,which could be further enhanced by the addition of multi-metal promotors.The electronic properties of promoters well explained their influence on CO_(2)adsorption behavior,while the binding energy of promoters had a good linear relationship with the CO_(2)activation barrier.Specifically,there existed a distance effect by the doped multi-metals.When the doped metals were adjacent to each other,it would be more beneficial for CO_(2)dissociation,and when they were far away from each other,it facilitated CO_(2)adsorption.Moreover,Mn atom is a good choice for forming dual-atom catalysts,which could significantly increase the adsorption stability of CO_(2)and facilitate the direct dissociation of CO_(2).展开更多
Elucidation the relationship between electrode potentials and heterogeneous electrocatalytic reactions has attracted widespread attention.Herein we construct the well-defined Mn single-atom(MnSA)catalyst with four N-c...Elucidation the relationship between electrode potentials and heterogeneous electrocatalytic reactions has attracted widespread attention.Herein we construct the well-defined Mn single-atom(MnSA)catalyst with four N-coordination through a simple thermal pyrolysis preparation method to investigate the electrode potential micro-environments effect on carbon dioxide reduction reactions(CO_(2)RR)and oxygen reduction reactions(ORR).MnSA catalysts generate higher CO production Faradaic efficiency of exceeding 90%at-0.9 V for CO_(2)RR and higher H_(2)O_(2)yield from 0.1 to 0.6 V with excellent ORR activity.Density functional theory(DFT)calculations based on constant potential models were performed to study the mechanism of MnSA on CO_(2)RR.The thermodynamic energy barrier of CO_(2)RR is lowest at-0.9 V vs.reversible hydrogen electrode(RHE).Similar DFT calculations on the H_(2)O_(2)yield of ORR showed that the H_(2)O_(2)yield at 0.2 V was higher.This study provides a reasonable explanation for the role of electrode potential micro-environments.展开更多
The human gastrointestinal tract accommodates an entire micro-environment for divergent physiologic processes,the dysbiosis of this micro-ecology has a strong inter-action with the pathogenesis of inflammatory bowel d...The human gastrointestinal tract accommodates an entire micro-environment for divergent physiologic processes,the dysbiosis of this micro-ecology has a strong inter-action with the pathogenesis of inflammatory bowel disease(IBD).In the past few years,with the advances in the understanding of microbiome,its metabolites and further application of next generation sequencing,analysis of dynamic alteration of gut micro-environment was realized,which provides numerous information beyond simple microbiota structure or metabolites differences under chronic colitis status.The subsequent intervention strategies targeting the modulation of intestinal micro-environment have been explored as a potential therapy.In this review,we will summarize the recent knowledge about multi-dimensional dysbiosis,the inter-action between fungus and bacteria under inflamed mucosa,and the clinical application of probiotics and fecal microbiota transplantation as a promising therapeutic approach in IBD.展开更多
Background:Schistosomiasis japonica is a chronic parasitic disease that seriously harms people's health.Oncomelonia hupensis is the only intermediate host of Schistosoma japonicum.Jhe micro-environmental factors s...Background:Schistosomiasis japonica is a chronic parasitic disease that seriously harms people's health.Oncomelonia hupensis is the only intermediate host of Schistosoma japonicum.Jhe micro-environmental factors surrounding the snail have a great impact on the survival,growth and reproduction of 0.hupensis,but there are few relevant systematic analyses until the present.This scoping review aims to identify and summarize the micro-environmental factors that greatly affect 0.hupensis,and to find gaps in research thus to provide directions for future in-depth studies.展开更多
Porous carbon spheres with an internal gridded hollow structure and microporous shell have always been attractive as carbon hosts for electrochemical energy storage. Such carbon hosts can limit active species loss and...Porous carbon spheres with an internal gridded hollow structure and microporous shell have always been attractive as carbon hosts for electrochemical energy storage. Such carbon hosts can limit active species loss and enhance electronic conductivity throughout the entire framework. Herein, a synthesis approach of internal gridded hollow carbon spheres is developed from solid polymer spheres rather than originally gridded polymer spheres under a controlled pyrolysis micro-environment. The crucial point of this approach is the fabrication of a silica fence around solid polymer spheres, under which the free escaping of the pyrolysis gas will be partly impeded, thus offering a reconstitution opportunity for an internal structure of solid polymer spheres. As a result, the interior of carbon spheres is sculptured into a gridded hollow structure with microporous skin. Furthermore, the size and density of carbon-bridge grids can be modulated by altering the crosslinking degree of polymer spheres and varying pyrolysis conditions. Such gridded hollow carbon spheres show good performance as sulfur hosts for Li-S battery.展开更多
Under the extremely cold climatic condition,crops have to survive severe heat stress conditions,even if they are being kept in greenhouses.In the winter and spring of North China,the air and soil temperature is low in...Under the extremely cold climatic condition,crops have to survive severe heat stress conditions,even if they are being kept in greenhouses.In the winter and spring of North China,the air and soil temperature is low inside the greenhouse,and when using a traditional heating system,the energy consumption is high.This paper reports on a study of different design solutions for a root zone heating system based on a kind of low temperature radiation material.Root zone heating systems offer increasing crop quality and productivity.A novel type of heat preservation and root zone heating system was applied in greenhouse seedling.And through multiple experiments,the effect of the root zone heating system on the ambient environment and seedbed surface was studied,and the heat preservation effect and heating uniformity were discussed.Results show that single-layer film covering on the root zone heating system can make the average temperature at night increase 1°C.And the average seedbed surface and substrate temperature can increase 11.3°C and 5.2°C,respectively.In conclusion,the root zone heating system can effectively improve the environmental temperature of seedling and the uniformity of heating is high,which provides a strong guarantee for high-quality seedling cultivation.展开更多
Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord injury.Microglia and astrocytes play key roles in the spinal cord injury micro-e...Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord injury.Microglia and astrocytes play key roles in the spinal cord injury micro-environment and share a close interaction.However,the mechanisms involved remain unclear.In this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming phenotypes.The expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord injury.In vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between them.We further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling pathway.This,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling pathways.In vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function recovery.Overall,Gas6 may play a role in the treatment of spinal cord injury.It can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord.展开更多
This editorial aimed to consolidate current evidence on the role of major endogenous modulators—nitric oxide(NO),prostaglandins(PGs),thromboxanes(TXs),and endothelins(ETs)in the lung carcinogenesis,their receptor-spe...This editorial aimed to consolidate current evidence on the role of major endogenous modulators—nitric oxide(NO),prostaglandins(PGs),thromboxanes(TXs),and endothelins(ETs)in the lung carcinogenesis,their receptor-specific actions,compensatory feedback mechanisms,and their role in tumor immune evasion and angiogenesis.We searched PubMed and Google Scholar with free-text and MeSH combinations of terms including"lung cancer","nitric oxide","inducible NOS","COX-2","prostaglandin E2","thromboxane A2","endothelin","angiogenesis",and"immunosuppression".We examined English-language publications for mechanistic data,preclinical models,and clinical correlates,and synthesized findings from both animal and human tissue studies.We highlight here the dual,concentration-dependent actions of NO,PG-E2's immunosup-pressive and pro-angiogenic actions via E-Prostanoid(EP2/EP4)receptors,thromboxane A2's pro-metastatic functions by thromboxane receptor signaling and interaction with platelet-tumor interaction,and the underappreciated roles of ETs.We also point to gaps in the existing literature on the differential roles of other prostanoid subtypes(e.g.,PGI2,PGD2),hypoxia-inducible factor-1α's role in regulation of inflammatory cascades,and clinical significance of compensatory upregulation of TX synthase following cycloxygenase-2 inhibition.These obse-rvations underscore the potential need for receptor-targeted therapies,biomarker-guided patient stratification,and improved translational models to inform the development of personalized anti-inflammatory interventions in lung cancer.展开更多
基金supported by the Research Fund for National Key Research and Development Program of China(2022YFA1503804,2021YFA1501403)the Natural Science Foundation of China(22208094,21922803,92034301,22008066 and 21776077)+2 种基金the China Postdoctoral Science Foundation(BX20190116)the Innovation Program of Shanghai Municipal Education Commission(17ZR1407300)the Program of Shanghai Academic/Technology Research Leader(21XD1421000).
文摘Essentially clearing the structure-activity relationship between iron carbide catalysts involving multiple active centers to understand the reaction mechanism of CO hydrogenation conversion process is still a great challenge.Here,two main micro-environment factors,namely electronic properties and geometrical effects were found to have an integrated effect on the mechanism of CO hydrogenation conversion,involving active sites on multiple crystal phases.The Bader charge of the surface Fe atoms on the active sites had a guiding effect on the CO activation pathway,while the spatial configuration of the active sites greatly affected the energy barriers of CO activation.Although the defective surfaces were more conducive to CO activation,the defective sites were not the only sites to dissociate CO,as CO always tended to dissociate in a wider area.This synergistic effect of the micro-environment also occurred during the CO conversion process.Surface C atoms on relatively flat configurations were more likely to form methane,while the electronic properties of the active sites could effectively describe the C-C coupling process,as well as distinguish the coupling mechanisms.
文摘Background:Recurrent implantation failure(RIF)is a difficult problem with a multifaceted cause.Recent studies have demonstrated that stimulator of interferon genes-induced immune-related genes(STIRGs)are associated with immune disorders that may affect the endometrial immune micro-environment.However,the effect of STRIGs on RIF remains unknown.Methods:Training(GSE111974)and validation(GSE106602)cohorts were acquired from the Gene Expression Omnibus database.STIRGs were extracted from the Molecular Signatures Database and relevant studies.Consensus clustering analysis was used to identify RIF molecular subtypes.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment and immune infiltration analyses were performed between RIF subtypes.Drug-related potential therapeutic target genes were discovered.Results:Two distinct molecular subtypes were discovered in both the training and validation groups according to STIRGs.In subtype C2,there was a notable decrease in the presence of different types of immune cells,such as natural killer cells and macrophages.Furthermore,the examination of Gene Ontology and Kyoto Encyclopedia of Genes and Genomes indicated a decrease in numerous immune-related biological processes within subtype C2.Finally,nine hub genes(CXCR4,POU5F1,PPARG,TLR2,EGFR,CSF1,BCL2A1,BTK,and SRGN)were identified as potential therapeutic targets for RIF.Conclusion:Based on STIRGs,we identified a new molecular subtype with significantly reduced immune infiltration in RIF.Nine genes might be potential therapeutic targets for RIF.
基金supported by the National Natural Science Foundation of China(22101182)the Shenzhen Science and Technology Program(Nos.JCYJ20210324095202006,JCYJ20220531095813031,and JCYJ20230807140700001)Guangdong Basic and Applied Basic Research Foundation(2022A1515010318).
文摘Surface functionalization of Cu-based catalysts has demonstrated promising potential for enhancing the electrochemical CO_(2)reduction reaction(CO_(2)RR)toward multi-carbon(C2+)products,primarily by suppressing the parasitic hydrogen evolution reaction and facilitating a localized CO_(2)/CO concentration at the electrode.Building upon this approach,we developed surface-functionalized catalysts with exceptional activity and selectivity for electrocatalytic CO_(2)RR to C_(2+)in a neutral electrolyte.Employing CuO nanoparticles coated with hexaethynylbenzene organic molecules(HEB-CuO NPs),a remarkable C_(2+)Faradaic efficiency of nearly 90%was achieved at an unprecedented current density of 300 mA cm^(-2),and a high FE(>80%)was maintained at a wide range of current densities(100-600 mA cm^(-2))in neutral environments using a flow cell.Furthermore,in a membrane electrode assembly(MEA)electrolyzer,86.14%FEC2+was achieved at a partial current density of 387.6 mA cm^(-2)while maintaining continuous operation for over 50 h at a current density of 200 mA cm^(-2).In-situ spectroscopy studies and molecular dynamics simulations reveal that reducing the coverage of coordinated K⋅H2O water increased the probability of intermediate reactants(CO)interacting with the surface,thereby promoting efficient C-C coupling and enhancing the yield of C_(2+)products.This advancement offers significant potential for optimizing local micro-environments for sustainable and highly efficient C_(2+)production.
基金the National Natural Science Foundation of China(51109214,31101074 and 51309211)the National Key Technology Research and Development Program of China(2011BAD32B)the Basic Scientific Research Foundation of National Non-Profit Scientific Institute of China(BSRF201303)
文摘The irrigation method used in winter wheat fields affects micro-environment factors, such as relative humidity(RH) within canopy, soil temperature, topsoil bulk density, soil matric potential, and soil nutrients, and these changes may affect plant root growth.An experiment was carried out to explore the effects of irrigation method on micro-environments and root distribution in a winter wheat field in the 2007–2008 and 2008–2009 growing seasons.The results showed that border irrigation(BI), sprinkler irrigation(SI), and surface drip irrigation(SDI) had no significant effects on soil temperature.Topsoil bulk density, RH within the canopy, soil available N distribution, and soil matric potential were significantly affected by the three treatments.The change in soil matric potential was the key reason for the altered root profile distribution patterns.Additionally, more fine roots were produced in the BI treatment when soil water content was low and topsoil bulk density was high.Root growth was most stimulated in the top soil layers and inhibited in the deep layers in the SDI treatment, followed by SI and BI, which was due to the different water application frequencies.As a result, the root profile distribution differed, depending on the irrigation method used.The root distribution pattern changes could be described by the power level variation in the exponential function.A good knowledge of root distribution patterns is important when attempting to model water and nutrient movements and when studying soil-plant interactions.
基金financially supported by National Natural Science Foundation of China(NSFC,Nos.81873921 and 51903174)Sino-German Cooperation Group Project(No.GZ1512)+2 种基金China Postdoctoral Science Foundation(No.2021M702772)Chengdu Science and Technology Program(No.2020-GH02-00007-HZ)Sichuan University Postdoctoral Interdisciplinary Innovation Startup Foundation and the Fundamental Research Funds for Central Universities(No.2021SCU12070)。
文摘The integrated lipopeptide(RVA)/gene complexes are fabricated with bi-directional regulation on tumor cells and micro-environment.After self-assembling and target coating modification,the poly(γ-glutamic acid)(γ-PGA)/RVA nano-vectors can sequentially respond to pH&redox stimuli,and guarantee efficient therapeutic gene delivery and control release of all-trans retinoic acid.The design provides a facile but promising strategy to treat refractory cancers.
基金supported by the National 973 Basic Research Program of China(No.2013CB733800)the National Natural Science Foundation of China(Nos.11272091 and 11102113)
文摘A three-dimensional (3D) mathematical model of tumour growth at the avascular phase and vessel remodelling in host tissues is proposed with emphasis on the study of the interactions of tumour growth and hypoxic micro-environment in host tissues. The hybrid based model includes the continuum part, such as the distributions of oxygen and vascular endothelial growth factors (VEGFs), and the discrete part of tumour cells (TCs) and blood vessel networks. The simulation shows the dynamic process of avascular tumour growth from a fewinitial cells to an equilibrium state with varied vessel networks. After a phase of rapidly increasing numbers of the TCs, more and more host vessels collapse due to the stress caused by the growing tumour. In addition, the consumption of oxygen expands with the enlarged tumour region. The study also discusses the effects of certain factors on tumour growth, including the density and configuration of pre- existing vessel networks and the blood oxygen content. The model enables us to examine the relationship between early tumour growth and hypoxic micro-environment in host tissues, which can be useful for further applications, such as tumour metastasis and the initialization of tumour angiogenesis.
文摘Three kinds of packaging bags composited with barrier film and moisture absorbents were designed in order to find out how to create an internal micro-environment with low O2content and relative humidity( RH). Peanuts with different moisture contents were filled into packaging bags and stored in an environmental chamber for a certain period of time. An RH recorder was sealed in each bag and the RH inside the bag was recorded. The moisture contents of peanuts before and after storage were measured as well.It is found that peanuts with moisture content of 13% can reduce O2content inside the bag by the aerobic respiration,achieving the self modified atmosphere packaging( MAP) effect. A microenvironment with lower RH can be created by using super-absorbent fiber( SAF) or mineral bag as the moisture absorbent. The moisture contents of peanuts stored in the bags with SAF and mineral bag as moisture absorbent decreased from 13% to 10. 5%and 11. 3%,respectively. SAF is a promising material of packaging bags composited with barrier film,in which a low RH and high CO2content can be created.
文摘The wax palm (Ceroxylon echinulatum) and palm heart (Prestoea acuminata) are key elements in Andean natural forests. This ecosystem is threatened by deforestation and habitat degradation, thus, it is vital to explore the impact of anthropogenic activities on the ecological structure and preferences of these species in order to develop proper conservation strategies. Fifty-seven 400 m2 plots were established in two forest areas, a disturbed forest (n = 30 plots) and an undisturbed forest (n = 27 plots) in the Ecuadorean Andes. Nine micro-environmental variables and the number of individuals of C. echinulatum and P. acuminata in five size classes were recorded in each plot. Logistic regression models helped identify environmental variables that influence the establishment of the species. Results showed that different micro-environmental variables determined the presence of different size classes. Both species were benefitted by the environmental conditions of the disturbed forest. Light availability was important for the establishment of both species, especially for the canopy species (C. echinulatum). This palm was negatively affected by the variable “fallen wood”, while P. acuminata was negatively affected mainly by the steepness of the terrain. The environmental variables for the successful establishment of the studied species that were identified by this study provide clues for the sustainable management of C. echinulatum and P. acuminata in Andean forests.
文摘Micro-environmental restriction effects to yeast cell growth obtained within Ca-alginate microbeads are considered. It is complex phenomenon influenced by: (1) relaxation of expanded polymer network around the cellular clusters, (2) forces generated by cell growth inside the beads and (3) interactions between solvent, network parts and cells. The resulting effects are measured experimentally by estimating volume of microbeads and yeast cell concentration as function of time of cultivation. Comparative analysis of dynamics of cell growth and increase of microbead volume through four regimes indicates that reversible and irreversible local structural changes of Ca-alginate hydrogel induces micro-environmental restrictions to cell growth. The mechanism of restrictions includes both mechanical and electrostatic effects.
文摘A small English class can be called as a micro-environment for English study. In this small micro-environment, the relationship between teachers and students is subtle. How to achieve the good interaction and create a good micro-environment in English class between teachers and students is very important for developing students' learning ability. This thesis is based on Rogers' humanistic teaching theory, which uses questionnaires, inteview and comparative analysis to analyze the current situation of micro-environment in college English learning. It discusses the construction of micro-environment in college English learning based on Rogers' humanistic teaching theory and the ways to construct it from software conditions (roles of teachers and students, relationship between teachers and students, the classroom atmosphere) and hardware conditions(teaching resources, a classroom).
基金supported by the Research Fund for National Key Research and Development Program of China(Nos.2021YFA1501403 and 2021YFB3500903)the National Natural Science Foundation of China(Nos.22208094,21922803,92034301,22008066,and 21776077)+2 种基金the China Postdoctoral Science Foundation(No.BX20190116)the Innovation Program of Shanghai Municipal Education Commission(No.17ZR1407300)the Program of Shanghai Academic/Technology Research Leader(No.21XD1421000).
文摘Essentially developing and regulating the unique electronic property of iron carbide catalysts involving multi-metal promoters to understand the structure–activity relationship of the CO_(2)activation process is still a great challenge.Here,metals and transition metals were introduced as strategies for electronic structure regulation to theoretically understand the underlying nature of CO_(2)adsorption and activation behaviors over Fe_(3)C catalysts.The distinctive micro-environment on the Fe_(3)C surface made it more conducive to CO_(2)adsorption and activation compared to other Fe-based catalysts,which could be further enhanced by the addition of multi-metal promotors.The electronic properties of promoters well explained their influence on CO_(2)adsorption behavior,while the binding energy of promoters had a good linear relationship with the CO_(2)activation barrier.Specifically,there existed a distance effect by the doped multi-metals.When the doped metals were adjacent to each other,it would be more beneficial for CO_(2)dissociation,and when they were far away from each other,it facilitated CO_(2)adsorption.Moreover,Mn atom is a good choice for forming dual-atom catalysts,which could significantly increase the adsorption stability of CO_(2)and facilitate the direct dissociation of CO_(2).
基金supported by the National Natural Science Foundation of China(Nos.52073214 and 22075211)Guangxi Natural Science Fund for Distinguished Young Scholars(No.2024GXNSFFA010008).
文摘Elucidation the relationship between electrode potentials and heterogeneous electrocatalytic reactions has attracted widespread attention.Herein we construct the well-defined Mn single-atom(MnSA)catalyst with four N-coordination through a simple thermal pyrolysis preparation method to investigate the electrode potential micro-environments effect on carbon dioxide reduction reactions(CO_(2)RR)and oxygen reduction reactions(ORR).MnSA catalysts generate higher CO production Faradaic efficiency of exceeding 90%at-0.9 V for CO_(2)RR and higher H_(2)O_(2)yield from 0.1 to 0.6 V with excellent ORR activity.Density functional theory(DFT)calculations based on constant potential models were performed to study the mechanism of MnSA on CO_(2)RR.The thermodynamic energy barrier of CO_(2)RR is lowest at-0.9 V vs.reversible hydrogen electrode(RHE).Similar DFT calculations on the H_(2)O_(2)yield of ORR showed that the H_(2)O_(2)yield at 0.2 V was higher.This study provides a reasonable explanation for the role of electrode potential micro-environments.
基金supported by a grant from the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(No.2016-12M-3-001).
文摘The human gastrointestinal tract accommodates an entire micro-environment for divergent physiologic processes,the dysbiosis of this micro-ecology has a strong inter-action with the pathogenesis of inflammatory bowel disease(IBD).In the past few years,with the advances in the understanding of microbiome,its metabolites and further application of next generation sequencing,analysis of dynamic alteration of gut micro-environment was realized,which provides numerous information beyond simple microbiota structure or metabolites differences under chronic colitis status.The subsequent intervention strategies targeting the modulation of intestinal micro-environment have been explored as a potential therapy.In this review,we will summarize the recent knowledge about multi-dimensional dysbiosis,the inter-action between fungus and bacteria under inflamed mucosa,and the clinical application of probiotics and fecal microbiota transplantation as a promising therapeutic approach in IBD.
文摘Background:Schistosomiasis japonica is a chronic parasitic disease that seriously harms people's health.Oncomelonia hupensis is the only intermediate host of Schistosoma japonicum.Jhe micro-environmental factors surrounding the snail have a great impact on the survival,growth and reproduction of 0.hupensis,but there are few relevant systematic analyses until the present.This scoping review aims to identify and summarize the micro-environmental factors that greatly affect 0.hupensis,and to find gaps in research thus to provide directions for future in-depth studies.
基金The authors are grateful to the financial support by the National Natural Science Foundation of China(Nos.21776041 and 21875028)Cheung Kong Scholars Programme of China(No.T2015036).
文摘Porous carbon spheres with an internal gridded hollow structure and microporous shell have always been attractive as carbon hosts for electrochemical energy storage. Such carbon hosts can limit active species loss and enhance electronic conductivity throughout the entire framework. Herein, a synthesis approach of internal gridded hollow carbon spheres is developed from solid polymer spheres rather than originally gridded polymer spheres under a controlled pyrolysis micro-environment. The crucial point of this approach is the fabrication of a silica fence around solid polymer spheres, under which the free escaping of the pyrolysis gas will be partly impeded, thus offering a reconstitution opportunity for an internal structure of solid polymer spheres. As a result, the interior of carbon spheres is sculptured into a gridded hollow structure with microporous skin. Furthermore, the size and density of carbon-bridge grids can be modulated by altering the crosslinking degree of polymer spheres and varying pyrolysis conditions. Such gridded hollow carbon spheres show good performance as sulfur hosts for Li-S battery.
基金This work was financially supported by the National Key Research and Development Program of China(Grant No.2017YFD0701500)and the Hebei Province Key Research and Development Program(Grant No.19227214D).
文摘Under the extremely cold climatic condition,crops have to survive severe heat stress conditions,even if they are being kept in greenhouses.In the winter and spring of North China,the air and soil temperature is low inside the greenhouse,and when using a traditional heating system,the energy consumption is high.This paper reports on a study of different design solutions for a root zone heating system based on a kind of low temperature radiation material.Root zone heating systems offer increasing crop quality and productivity.A novel type of heat preservation and root zone heating system was applied in greenhouse seedling.And through multiple experiments,the effect of the root zone heating system on the ambient environment and seedbed surface was studied,and the heat preservation effect and heating uniformity were discussed.Results show that single-layer film covering on the root zone heating system can make the average temperature at night increase 1°C.And the average seedbed surface and substrate temperature can increase 11.3°C and 5.2°C,respectively.In conclusion,the root zone heating system can effectively improve the environmental temperature of seedling and the uniformity of heating is high,which provides a strong guarantee for high-quality seedling cultivation.
基金supported by the National Natural Science Foundation of China, Nos.81971151 (to YW), 82102528 (to XL), 82102583 (to LW)the Natural Science Foundation of Guangdong Province, China, Nos.2020A1515010265 (to YW), 2020A1515110679 (to XL), and 2021A1515010358 (to XL)
文摘Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord injury.Microglia and astrocytes play key roles in the spinal cord injury micro-environment and share a close interaction.However,the mechanisms involved remain unclear.In this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming phenotypes.The expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord injury.In vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between them.We further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling pathway.This,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling pathways.In vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function recovery.Overall,Gas6 may play a role in the treatment of spinal cord injury.It can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord.
文摘This editorial aimed to consolidate current evidence on the role of major endogenous modulators—nitric oxide(NO),prostaglandins(PGs),thromboxanes(TXs),and endothelins(ETs)in the lung carcinogenesis,their receptor-specific actions,compensatory feedback mechanisms,and their role in tumor immune evasion and angiogenesis.We searched PubMed and Google Scholar with free-text and MeSH combinations of terms including"lung cancer","nitric oxide","inducible NOS","COX-2","prostaglandin E2","thromboxane A2","endothelin","angiogenesis",and"immunosuppression".We examined English-language publications for mechanistic data,preclinical models,and clinical correlates,and synthesized findings from both animal and human tissue studies.We highlight here the dual,concentration-dependent actions of NO,PG-E2's immunosup-pressive and pro-angiogenic actions via E-Prostanoid(EP2/EP4)receptors,thromboxane A2's pro-metastatic functions by thromboxane receptor signaling and interaction with platelet-tumor interaction,and the underappreciated roles of ETs.We also point to gaps in the existing literature on the differential roles of other prostanoid subtypes(e.g.,PGI2,PGD2),hypoxia-inducible factor-1α's role in regulation of inflammatory cascades,and clinical significance of compensatory upregulation of TX synthase following cycloxygenase-2 inhibition.These obse-rvations underscore the potential need for receptor-targeted therapies,biomarker-guided patient stratification,and improved translational models to inform the development of personalized anti-inflammatory interventions in lung cancer.