Sulfate attack-induced expansion of cement-treated aggregates in seasonally frozen regions is a well-known issue which causes continuous expansion in railway subgrades,and particularly in high-speed railways.According...Sulfate attack-induced expansion of cement-treated aggregates in seasonally frozen regions is a well-known issue which causes continuous expansion in railway subgrades,and particularly in high-speed railways.Accordingly,we investigated the influence of material proportions,the number of freeze-thaw(FT)cycles,and temperature gradients on the expansion mechanism of sulfate attack on cement-treated aggregates subjected to FT cycles.The conditions,laws,and dominant factors causing the expansion of aggregates were analyzed through swelling tests.The results indicate that under FT cycles,3%content cement-treated graded macadam only experiences slight deformation.The maximum strain of graded macadam attacked by 1%sodium sulfate content in each FT cycle is significantly larger than that of 3%content cement-treated graded macadam attacked by 1%sodium sulfate content.Using scanning electron microscopy,needle-like crystals were observed during sulfate attack of cement-treated graded macadam.Through quantitative analysis,we determined the recoverable and unrecoverable deformations of graded macadam under FT cycles.For graded macadam under sulfate attack,the expansion is mainly induced by periodic frost heave and salt expansion,as well as salt migration.For cement-treated graded macadam under sulfate attack,the expansion is mainly induced by chemical attack and salt migration.This study can serve as a reference for future research on the mechanics of sulfate attack on cement-treated aggregates that experience FT cycles,and provide theoretical support for methods that remediate the expansion induced by sulfate attack.展开更多
Lithium (Li) metal batteries (LMBs) featuring ultrahigh energy densities are expected as ones of the mostprominent devices for future energy storage applications. Nevertheless, the practical application of LMBs is sti...Lithium (Li) metal batteries (LMBs) featuring ultrahigh energy densities are expected as ones of the mostprominent devices for future energy storage applications. Nevertheless, the practical application of LMBs is stillplagued by the poor interfacial stability of Li metal anode. Inorganic-rich interlayer derived from anion decom-positionin advanced liquid electrolytes is demonstrated as an efficient approach to stabilize the Li metal anode,however, is electrolyte-dependent with limited application conditions due to inappropriate electrolyte properties.Herein, an efficient structuration strategy is proposed to fabricate an electrolyte-independent and sustainedinorganic-rich layer, by embedding a type of functional anion aggregates consisting of selected anions ionicallybonded to polymerized cation clusters. The anion aggregates can progressively release anions to react with Liþand form key components boosting the structural stability and Liþ transfer ability of the artificial layer uponcycling. This self-reinforcing working mechanism endows the artificial layer with a sustained inorganic-richnature and promising Li protective ability during long-term cycling, while the electrolyte-independent propertyenables its applications in LMBs using conventional low concentration electrolytes and all-solid-state LMBs withsignificantly enhanced performances. This strategy establishes an alternative designing route of Li protectivelayers for reliable LMBs.展开更多
The publisher regrets to inform that in the article of Advanced Powder Materials 4(2025)100261,the published Figs.3 and 5 belong to the initially submitted version,which should be replaced by the final version.The dif...The publisher regrets to inform that in the article of Advanced Powder Materials 4(2025)100261,the published Figs.3 and 5 belong to the initially submitted version,which should be replaced by the final version.The differences between the initial and final versions of these figures are described below.展开更多
The degradation performance of pervious concrete containing TiO_(2)/LDHs-loaded recycled aggregates for NO gas was analyzed using a gas phase catalytic degradation test device,simulating different environmental condit...The degradation performance of pervious concrete containing TiO_(2)/LDHs-loaded recycled aggregates for NO gas was analyzed using a gas phase catalytic degradation test device,simulating different environmental conditions such as load,ambient temperature,and illumination intensity,which provides theoretical support for practical engineering.The experimental results indicate that when the ambient temperature is controlled at 25℃and the illumination intensity is 30 W/m^(2),the sample prepared by soaking recycled aggregates in a 0.8%TiO_(2)/LDHs suspension exhibits the highest photocatalytic degradation rate for NO gas,reaching 72.54%.Further investigation on the influence of environmental temperature reveals that,at 25℃,the maximum photocatalytic degradation rate for NO gas is 72.9%.Moreover,at an illumination intensity of 40 W/m^(2),the maximum photocatalytic degradation rate for NO gas is 87.08%.Additionally,after three repeated photocatalytic tests,the sample demonstrates good stability,with a photocatalytic degradation rate of 58%.The nitrogen content in the eluent obtained from soaking the sample was determined to be 0.0022 mol/L,with a recovery rate of 80%.The adsorption experiment demonstrates that the sample exhibits a favorable adsorption effect on nitrate ions,reaching a maximum of 56.8%.展开更多
The agro-pastoral ecotone epitomizes the ecologically fragile semi-arid zone,where the soil microbiomes play a pivotal role in regulating its multifunctionality.However,whether and how changes in soil structure and or...The agro-pastoral ecotone epitomizes the ecologically fragile semi-arid zone,where the soil microbiomes play a pivotal role in regulating its multifunctionality.However,whether and how changes in soil structure and organic matter composition under different land uses affect microbial community structure remain unclear.Here,land-use types in the agro-pastoral ecotone,including shrubland(BF),artificial grassland(ArG),abandoned grassland(AbG),and maize farmland(MA),were chosen to explore the response relationships between soil microbial communities and the aggregates and dissolved organic matter(DOM)composition.The results showed that compared to MA,the macroaggregates in BF,AbG,and ArG were increased by 123.0,92.79,and 63.71%,respectively,while MA soil had the greatest abundance of<100μm particles.The higher aromatic carbon with high aromaticity and molecular weight in BF soil DOM contributed to its highest mineral-associated organic carbon level(12.61 g kg^(-1)),while MA soil organic carbon had highly efficient decomposition due to its high content of aliphatic and carboxy carbon,so it is prone to loss from the active carbon pools.The transition in land use from shrubland to grassland and farmland has facilitated the conversion of stable aromatic carbon to unstable carboxy carbon.The taxonomic analysis revealed that soil bacterial and fungal communities in the four land uses were dominated by Proteobacteria,Actinobacteriota,Chloroflexi,and Ascomycota.More taxonomic groups from phylum to family were enriched in BF soil.The DOM components and organic carbon are crucial variables shaping the composition of soil bacterial communities,jointly explaining 61.66% of the variance,while aggregates are important variables driving the composition of fungal communities,with an explanation rate of 20.49%.Our results suggest that DOM components and aggregates impact the soil microbial structure;and the transition in land use from agricultural land to grassland and shrubland in the agro-pastoral ecotone enhances aggregate stability,carbon sequestration potential,and microbial diversity.展开更多
Global climate change exerts profound effects on snow cover,with consequential impacts on microbial activities and the stability of soil organic carbon(SOC)within aggregates.Northern peatlands are significant carbon r...Global climate change exerts profound effects on snow cover,with consequential impacts on microbial activities and the stability of soil organic carbon(SOC)within aggregates.Northern peatlands are significant carbon reservoirs,playing a critical role in mitigating climate change.However,the effects of snow variations on microbial-mediated SOC stability within aggregates in peatlands remain inadequately understood.Here,an in-situ field experiment manipulating snow conditions(i.e.,snow removal and snow cover)was conducted to investigate how snow variations affect soil microbial community and the associated SOC stability within soil aggregates(>2,0.25-2,and<0.25 mm)in a peatland of Northeast China.The results showed that snow removal significantly increased the SOC content and stability within aggregates.Compared to the soils with snow cover,snow removal resulted in decreased soil average temperatures in the topsoil(0-30 cm depth)and subsoil(30-60 cm depth)(by 1.48 and 1.34°C,respectively)and increased freeze-thaw cycles(by 11 cycles),consequently decreasing the stability of aggregates in the topsoil and subsoil(by 23.68%and 6.85%,respectively).Furthermore,more recalcitrant carbon and enhanced SOC stability were present in microaggregates(<0.25 mm)at two soil depths.Moreover,reductions in bacterial diversity and network stability were observed in response to snow removal.Structural equation modeling analysis demonstrated that snow removal indirectly promoted(P<0.01)SOC stability by regulating carbon to nitrogen(C:N)ratio within aggregates.Overall,our study suggested that microaggregate protection and an appropriate C:N ratio enhanced carbon sequestration in response to climate change.展开更多
Microporous MgO–MgAl_(2)O_(4)refractory aggregates were prepared using calcined MgO powder andα-Al_(2)O_(3)micro-powder as raw materials.The influence ofα-Al_(2)O_(3)micro-powder addition on the microstructures and...Microporous MgO–MgAl_(2)O_(4)refractory aggregates were prepared using calcined MgO powder andα-Al_(2)O_(3)micro-powder as raw materials.The influence ofα-Al_(2)O_(3)micro-powder addition on the microstructures and properties of the aggregates was investigated.The results indicated that the addition ofα-Al_(2)O_(3)micro-powder to MgO powder not only promoted more pores in the MgO powder to being enclosed,but also caused the pores among the MgO powder to become micronano scale by the formation of continuous microporous MgAl_(2)O_(4)bonding layers,which reduced the thermal conductivity of the aggregates.Furthermore,the microporous MgAl_(2)O_(4)can induce crack deflection and generate crack branching when subjected to thermal shock,thus improving the thermal shock resistance of the microporous aggregates.The sample with 12.1 wt.%α-Al_(2)O_(3)micro-powder addition exhibited the best comprehensive properties,with a bulk density of 3.44 g/cm^(3),a median pore size of 120.7 nm,a high flexural strength of 82.7 MPa,a high retention rate of flexural strength of 87.7%,and a thermal conductivity of 8.4 W/(m K)at 800°C.Compared to commercial fused magnesia and sintered magnesia,the thermal conductivity decreased by 47.2%and 18.4%at 800°C,respectively.展开更多
食源性蛋白淀粉样纤维化聚集具有独特的结构特性,蚕豆11S蛋白(fava bean 11S protein,FP)作为一种可持续蛋白资源,表现出巨大的潜力。该研究探究了蚕豆11S蛋白淀粉样纤维化聚集(fibrotic aggregation of 11S protein in fava bean,FPF)...食源性蛋白淀粉样纤维化聚集具有独特的结构特性,蚕豆11S蛋白(fava bean 11S protein,FP)作为一种可持续蛋白资源,表现出巨大的潜力。该研究探究了蚕豆11S蛋白淀粉样纤维化聚集(fibrotic aggregation of 11S protein in fava bean,FPF)在形成过程中的动态演变,包括其结构表征和功能特性。6 g/100 mL的FP通过酸热处理(pH 2,85℃)不同时间(0~24 h)后得到FPF。处理后的样品通过硫黄素T、荧光、二酪氨酸、透射电子显微镜、傅里叶红外光谱等进行结构表征,结果表明FP先在酸热过程中水解成多肽,再自组装成富含β-折叠结构的FPF(由0 h的34.44%增加到24 h的45.89%)。通过起泡性、乳化性和凝胶特性等对FPF功能特性进行表征,与FP相比,反应24 h后的FPF具有更好的起泡性、乳化性和凝胶特性。此外,FPF在体外细胞实验中没有表现出细胞毒性。研究结果为FPF的形成规律提供了理论支撑。展开更多
[Objective]The research aimed to provide scientific reference for reasonable utilization of polyacrylamide(PAM).[Method]After PAM treatment,the soil aggregates were classified through dry sieve analysis and the adsorp...[Objective]The research aimed to provide scientific reference for reasonable utilization of polyacrylamide(PAM).[Method]After PAM treatment,the soil aggregates were classified through dry sieve analysis and the adsorption capacity and desorption capacity of all soil aggregates to phosphorus at different phosphorus concentrations were analyzed.[Result] The phosphorus adsorption and desorption of soil sample treated by PAM declined. The amount of phosphorus adsorption increased with the increase of phosphorus concentration and this increase was fast in low phosphorus concentration area but slow in high phosphorus concentration area.At different phosphorus concentrations,adsorption showed a へ shape changing trend.The phosphorus adsorption was related to phosphorus concentration and the 2-3 mm aggregate had the highest desorption rate while 0.1-0.25 mm aggregate and 0.45-1 mm aggregate had lowest desorption rate.[Conclusion]The PAM treatment generated significant influence on phosphorus adsorption and analytic features of aggregate in all size fractions.展开更多
Protein aggregates,mitochondrial import stress and neurodegenerative disorders:A salient hallmark of several neurodegenerative diseases,including Parkinson’s disease,is the abundance of protein aggregates(Goiran et a...Protein aggregates,mitochondrial import stress and neurodegenerative disorders:A salient hallmark of several neurodegenerative diseases,including Parkinson’s disease,is the abundance of protein aggregates(Goiran et al.,2022).This molecular event is believed to lead to activation of stress pathways ultimately resulting in cellular dysfunction(Eldeeb et al.,2022).Accordingly,many lines of research investigations focused on dampening the formation of protein aggregates or augmenting the clearance of protein aggregates as a potential therapeutic strategy to counteract the progression of neurodegenerative diseases,albeit with little success(Costa-Mattioli and Walter,2020).Cell stress cues such as the accumulation of protein aggregates lead to the activation of stress response pathways that aid cells in responding to the damage.Despite the notion that the transient activation of these pathways helps cells cope with stressors,persistent activation can induce unwanted apoptosis of cells and reduce overall tissue strength as well as lead to an accumulation of aggregation-prone proteins(Hetz and Papa,2018).Mutations in proteins involved in stress signaling termination can cause conditions like ataxia and early-onset dementia(Conroy et al.,2014).Therefore,it is crucial for stress response signaling to be turned off once conditions have improved.Nevertheless,the mechanisms by which cells silence these signals are still elusive.展开更多
Autophagy is well-known for delivering cargo materials to lysosomes for proteolytic digestion.Recently,autophagy has emerged as a key mechanism in unconventional protein secretion(UPS).This perspective introduces unco...Autophagy is well-known for delivering cargo materials to lysosomes for proteolytic digestion.Recently,autophagy has emerged as a key mechanism in unconventional protein secretion(UPS).This perspective introduces unconventional secretion pathways,focusing on secretory autophagy and its role in secreting protein aggregates associated with neurodegenerative disorders.We also explore additional neuronal functions of secretory autophagy beyond the release of protein aggregates.We propose autophagosomes as transport organelles that deliver cargo material directly from the endoplasmatic reticulum(ER)to the plasma membrane rather than solely to lysosomes.展开更多
Neuroinflammation is a key process in the pathogenesis of various neurodegenerative diseases,such as multiple sclerosis(MS),Alzheimer's disease,and traumatic brain injury.Even for disorders historically unrelated ...Neuroinflammation is a key process in the pathogenesis of various neurodegenerative diseases,such as multiple sclerosis(MS),Alzheimer's disease,and traumatic brain injury.Even for disorders historically unrelated to neuroinflammation,such as Alzheimer's disease,it is now shown to precede pathological protein aggregations.展开更多
[Objective] This study was conducted to investigate the effects of tradition-al fertilization and formula fertilization by soil testing on the chemical forms of nitro-gen in dark brown soil and its distribution in dif...[Objective] This study was conducted to investigate the effects of tradition-al fertilization and formula fertilization by soil testing on the chemical forms of nitro-gen in dark brown soil and its distribution in different aggregates. [Method] A physi-co-chemistry method was adopted in a comparative study on the chemical forms of nitrogen and their distribution in different-sized aggregates of dark brown soil under traditional fertilization and formula fertilization by soil testing respectively. [Result] Compared with traditional fertilization in spring and autumn, the formula fertilization by soil testing averagely decreased, the total nitrogen in soil by 23.2% in spring and by 20% in autumn in the soil layer of 0-20 cm, by 48.8% in the layer of 20-40 cm. Ammonium nitrogen was so sensitive to the methods of fertilization that the content of ammonium nitrogen was reduced much more under formula fertitization by soil testing in autumn than under traditional fertilization. Nitrogen in soil under traditional fertilization pattern was mainly distributed in the aggregates of 0-0.25 and 0.5-1 mm, while in formula fertilization by soil testing it was mainly distributed in the aggregates of 0.25-0.5 and 0-0.25 mm. [Conclusion] The study proved that for-mula fertilization by soil testing helped to reduce the risk of nitrogen pol ution and had huge effects on the chemical forms and distribution of nitrogen in different ag-gregates in dark brown soil.展开更多
To investigate migration and evolution rules of coarse aggregates in the static compaction process, an algorithm of generating digital coarse aggregates that can reflect real morphology（ such as shape, size and fract...To investigate migration and evolution rules of coarse aggregates in the static compaction process, an algorithm of generating digital coarse aggregates that can reflect real morphology（ such as shape, size and fracture surface） of aggregate particles, is represented by polyhedral particles based on the discrete element method（ DEM）. A digital specimen comprised of aggregates and air voids is developed. In addition,a static compaction model consisting of a digital specimen and three plates is constructed and a series of evaluation indices such as mean contact force σMCF, wall stress in direction of zcoordinate σWSZZ, porosity and coordination numbers are presented to investigate the motion rules of coarse aggregates at different compaction displacements of 7. 5, 15 and 30 mm. The three-dimensional static compaction model is also verified with laboratory measurements. The results indicate that the compaction displacements are positively related to σMCF and σWSZZ, which increase gradually with the increase in iterative steps. When the compaction proceeds, the digital specimen porosity decreases, but the coordination number increases. The variation ranges of these four indices are different at different compaction displacements. This study provides a method to analyze the compaction mechanism of particle materials such as asphalt mixture and graded broken stone.展开更多
基金National Natural Science Foundation of China(Nos.42171130 and 42301158)Pilot Project of China’s Strength in Transportation for the Central Research Institute(No.QG2021-1-4-7)National Key Technology Research and Development Program of the Ministry of Science and Technology of China(No.2021YFB2601200).
文摘Sulfate attack-induced expansion of cement-treated aggregates in seasonally frozen regions is a well-known issue which causes continuous expansion in railway subgrades,and particularly in high-speed railways.Accordingly,we investigated the influence of material proportions,the number of freeze-thaw(FT)cycles,and temperature gradients on the expansion mechanism of sulfate attack on cement-treated aggregates subjected to FT cycles.The conditions,laws,and dominant factors causing the expansion of aggregates were analyzed through swelling tests.The results indicate that under FT cycles,3%content cement-treated graded macadam only experiences slight deformation.The maximum strain of graded macadam attacked by 1%sodium sulfate content in each FT cycle is significantly larger than that of 3%content cement-treated graded macadam attacked by 1%sodium sulfate content.Using scanning electron microscopy,needle-like crystals were observed during sulfate attack of cement-treated graded macadam.Through quantitative analysis,we determined the recoverable and unrecoverable deformations of graded macadam under FT cycles.For graded macadam under sulfate attack,the expansion is mainly induced by periodic frost heave and salt expansion,as well as salt migration.For cement-treated graded macadam under sulfate attack,the expansion is mainly induced by chemical attack and salt migration.This study can serve as a reference for future research on the mechanics of sulfate attack on cement-treated aggregates that experience FT cycles,and provide theoretical support for methods that remediate the expansion induced by sulfate attack.
基金supported by the Research Fund of Jianghan Univer-sity(2024JCYJ02)the Graduate Scientific Research Foundation of Jianghan University(KYCXJJ202428)+1 种基金the Excellent Discipline Cultiva-tion Project funded by Jianghan University(2023XKZ013)the Na-tional Natural Science Foundation of China(Grant No.22179052).
文摘Lithium (Li) metal batteries (LMBs) featuring ultrahigh energy densities are expected as ones of the mostprominent devices for future energy storage applications. Nevertheless, the practical application of LMBs is stillplagued by the poor interfacial stability of Li metal anode. Inorganic-rich interlayer derived from anion decom-positionin advanced liquid electrolytes is demonstrated as an efficient approach to stabilize the Li metal anode,however, is electrolyte-dependent with limited application conditions due to inappropriate electrolyte properties.Herein, an efficient structuration strategy is proposed to fabricate an electrolyte-independent and sustainedinorganic-rich layer, by embedding a type of functional anion aggregates consisting of selected anions ionicallybonded to polymerized cation clusters. The anion aggregates can progressively release anions to react with Liþand form key components boosting the structural stability and Liþ transfer ability of the artificial layer uponcycling. This self-reinforcing working mechanism endows the artificial layer with a sustained inorganic-richnature and promising Li protective ability during long-term cycling, while the electrolyte-independent propertyenables its applications in LMBs using conventional low concentration electrolytes and all-solid-state LMBs withsignificantly enhanced performances. This strategy establishes an alternative designing route of Li protectivelayers for reliable LMBs.
文摘The publisher regrets to inform that in the article of Advanced Powder Materials 4(2025)100261,the published Figs.3 and 5 belong to the initially submitted version,which should be replaced by the final version.The differences between the initial and final versions of these figures are described below.
基金Funded by the National Natural Science Foundation of China(No.52478281)the Natural Science Foundation of Zhejiang Province(No.LZ22E080003)the Science and Technology Project of Zhejiang Provincial Department of Transport(No.202225)。
文摘The degradation performance of pervious concrete containing TiO_(2)/LDHs-loaded recycled aggregates for NO gas was analyzed using a gas phase catalytic degradation test device,simulating different environmental conditions such as load,ambient temperature,and illumination intensity,which provides theoretical support for practical engineering.The experimental results indicate that when the ambient temperature is controlled at 25℃and the illumination intensity is 30 W/m^(2),the sample prepared by soaking recycled aggregates in a 0.8%TiO_(2)/LDHs suspension exhibits the highest photocatalytic degradation rate for NO gas,reaching 72.54%.Further investigation on the influence of environmental temperature reveals that,at 25℃,the maximum photocatalytic degradation rate for NO gas is 72.9%.Moreover,at an illumination intensity of 40 W/m^(2),the maximum photocatalytic degradation rate for NO gas is 87.08%.Additionally,after three repeated photocatalytic tests,the sample demonstrates good stability,with a photocatalytic degradation rate of 58%.The nitrogen content in the eluent obtained from soaking the sample was determined to be 0.0022 mol/L,with a recovery rate of 80%.The adsorption experiment demonstrates that the sample exhibits a favorable adsorption effect on nitrate ions,reaching a maximum of 56.8%.
基金funded by the Inner Mongolia Local Science and Technology Development Fund Projects,China(2021GG0393)。
文摘The agro-pastoral ecotone epitomizes the ecologically fragile semi-arid zone,where the soil microbiomes play a pivotal role in regulating its multifunctionality.However,whether and how changes in soil structure and organic matter composition under different land uses affect microbial community structure remain unclear.Here,land-use types in the agro-pastoral ecotone,including shrubland(BF),artificial grassland(ArG),abandoned grassland(AbG),and maize farmland(MA),were chosen to explore the response relationships between soil microbial communities and the aggregates and dissolved organic matter(DOM)composition.The results showed that compared to MA,the macroaggregates in BF,AbG,and ArG were increased by 123.0,92.79,and 63.71%,respectively,while MA soil had the greatest abundance of<100μm particles.The higher aromatic carbon with high aromaticity and molecular weight in BF soil DOM contributed to its highest mineral-associated organic carbon level(12.61 g kg^(-1)),while MA soil organic carbon had highly efficient decomposition due to its high content of aliphatic and carboxy carbon,so it is prone to loss from the active carbon pools.The transition in land use from shrubland to grassland and farmland has facilitated the conversion of stable aromatic carbon to unstable carboxy carbon.The taxonomic analysis revealed that soil bacterial and fungal communities in the four land uses were dominated by Proteobacteria,Actinobacteriota,Chloroflexi,and Ascomycota.More taxonomic groups from phylum to family were enriched in BF soil.The DOM components and organic carbon are crucial variables shaping the composition of soil bacterial communities,jointly explaining 61.66% of the variance,while aggregates are important variables driving the composition of fungal communities,with an explanation rate of 20.49%.Our results suggest that DOM components and aggregates impact the soil microbial structure;and the transition in land use from agricultural land to grassland and shrubland in the agro-pastoral ecotone enhances aggregate stability,carbon sequestration potential,and microbial diversity.
基金supported by the National Natural Science Foundation of China(Nos.42222102,41971136,and 42171107)the Jilin Provincial Department of Science and Technology,China(No.20230508089RC)the Professional Association of the Alliance of International Science Organizations(No.ANSO-PA-2020-14).
文摘Global climate change exerts profound effects on snow cover,with consequential impacts on microbial activities and the stability of soil organic carbon(SOC)within aggregates.Northern peatlands are significant carbon reservoirs,playing a critical role in mitigating climate change.However,the effects of snow variations on microbial-mediated SOC stability within aggregates in peatlands remain inadequately understood.Here,an in-situ field experiment manipulating snow conditions(i.e.,snow removal and snow cover)was conducted to investigate how snow variations affect soil microbial community and the associated SOC stability within soil aggregates(>2,0.25-2,and<0.25 mm)in a peatland of Northeast China.The results showed that snow removal significantly increased the SOC content and stability within aggregates.Compared to the soils with snow cover,snow removal resulted in decreased soil average temperatures in the topsoil(0-30 cm depth)and subsoil(30-60 cm depth)(by 1.48 and 1.34°C,respectively)and increased freeze-thaw cycles(by 11 cycles),consequently decreasing the stability of aggregates in the topsoil and subsoil(by 23.68%and 6.85%,respectively).Furthermore,more recalcitrant carbon and enhanced SOC stability were present in microaggregates(<0.25 mm)at two soil depths.Moreover,reductions in bacterial diversity and network stability were observed in response to snow removal.Structural equation modeling analysis demonstrated that snow removal indirectly promoted(P<0.01)SOC stability by regulating carbon to nitrogen(C:N)ratio within aggregates.Overall,our study suggested that microaggregate protection and an appropriate C:N ratio enhanced carbon sequestration in response to climate change.
基金financially supported by the Key Projects of the National Natural Science Foundation of China(No.U21A2058)the Innovation Group Project of Natural Science Foundation of Hubei Province(2025AFA016).
文摘Microporous MgO–MgAl_(2)O_(4)refractory aggregates were prepared using calcined MgO powder andα-Al_(2)O_(3)micro-powder as raw materials.The influence ofα-Al_(2)O_(3)micro-powder addition on the microstructures and properties of the aggregates was investigated.The results indicated that the addition ofα-Al_(2)O_(3)micro-powder to MgO powder not only promoted more pores in the MgO powder to being enclosed,but also caused the pores among the MgO powder to become micronano scale by the formation of continuous microporous MgAl_(2)O_(4)bonding layers,which reduced the thermal conductivity of the aggregates.Furthermore,the microporous MgAl_(2)O_(4)can induce crack deflection and generate crack branching when subjected to thermal shock,thus improving the thermal shock resistance of the microporous aggregates.The sample with 12.1 wt.%α-Al_(2)O_(3)micro-powder addition exhibited the best comprehensive properties,with a bulk density of 3.44 g/cm^(3),a median pore size of 120.7 nm,a high flexural strength of 82.7 MPa,a high retention rate of flexural strength of 87.7%,and a thermal conductivity of 8.4 W/(m K)at 800°C.Compared to commercial fused magnesia and sintered magnesia,the thermal conductivity decreased by 47.2%and 18.4%at 800°C,respectively.
文摘[Objective]The research aimed to provide scientific reference for reasonable utilization of polyacrylamide(PAM).[Method]After PAM treatment,the soil aggregates were classified through dry sieve analysis and the adsorption capacity and desorption capacity of all soil aggregates to phosphorus at different phosphorus concentrations were analyzed.[Result] The phosphorus adsorption and desorption of soil sample treated by PAM declined. The amount of phosphorus adsorption increased with the increase of phosphorus concentration and this increase was fast in low phosphorus concentration area but slow in high phosphorus concentration area.At different phosphorus concentrations,adsorption showed a へ shape changing trend.The phosphorus adsorption was related to phosphorus concentration and the 2-3 mm aggregate had the highest desorption rate while 0.1-0.25 mm aggregate and 0.45-1 mm aggregate had lowest desorption rate.[Conclusion]The PAM treatment generated significant influence on phosphorus adsorption and analytic features of aggregate in all size fractions.
文摘Protein aggregates,mitochondrial import stress and neurodegenerative disorders:A salient hallmark of several neurodegenerative diseases,including Parkinson’s disease,is the abundance of protein aggregates(Goiran et al.,2022).This molecular event is believed to lead to activation of stress pathways ultimately resulting in cellular dysfunction(Eldeeb et al.,2022).Accordingly,many lines of research investigations focused on dampening the formation of protein aggregates or augmenting the clearance of protein aggregates as a potential therapeutic strategy to counteract the progression of neurodegenerative diseases,albeit with little success(Costa-Mattioli and Walter,2020).Cell stress cues such as the accumulation of protein aggregates lead to the activation of stress response pathways that aid cells in responding to the damage.Despite the notion that the transient activation of these pathways helps cells cope with stressors,persistent activation can induce unwanted apoptosis of cells and reduce overall tissue strength as well as lead to an accumulation of aggregation-prone proteins(Hetz and Papa,2018).Mutations in proteins involved in stress signaling termination can cause conditions like ataxia and early-onset dementia(Conroy et al.,2014).Therefore,it is crucial for stress response signaling to be turned off once conditions have improved.Nevertheless,the mechanisms by which cells silence these signals are still elusive.
基金supported by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)grant LU 2347/3-1(to PL).
文摘Autophagy is well-known for delivering cargo materials to lysosomes for proteolytic digestion.Recently,autophagy has emerged as a key mechanism in unconventional protein secretion(UPS).This perspective introduces unconventional secretion pathways,focusing on secretory autophagy and its role in secreting protein aggregates associated with neurodegenerative disorders.We also explore additional neuronal functions of secretory autophagy beyond the release of protein aggregates.We propose autophagosomes as transport organelles that deliver cargo material directly from the endoplasmatic reticulum(ER)to the plasma membrane rather than solely to lysosomes.
基金supported by FWO(Fonds voor Wetenschappelijk Onderzoek),grant number G07562NFWO(to BB)。
文摘Neuroinflammation is a key process in the pathogenesis of various neurodegenerative diseases,such as multiple sclerosis(MS),Alzheimer's disease,and traumatic brain injury.Even for disorders historically unrelated to neuroinflammation,such as Alzheimer's disease,it is now shown to precede pathological protein aggregations.
文摘[Objective] This study was conducted to investigate the effects of tradition-al fertilization and formula fertilization by soil testing on the chemical forms of nitro-gen in dark brown soil and its distribution in different aggregates. [Method] A physi-co-chemistry method was adopted in a comparative study on the chemical forms of nitrogen and their distribution in different-sized aggregates of dark brown soil under traditional fertilization and formula fertilization by soil testing respectively. [Result] Compared with traditional fertilization in spring and autumn, the formula fertilization by soil testing averagely decreased, the total nitrogen in soil by 23.2% in spring and by 20% in autumn in the soil layer of 0-20 cm, by 48.8% in the layer of 20-40 cm. Ammonium nitrogen was so sensitive to the methods of fertilization that the content of ammonium nitrogen was reduced much more under formula fertitization by soil testing in autumn than under traditional fertilization. Nitrogen in soil under traditional fertilization pattern was mainly distributed in the aggregates of 0-0.25 and 0.5-1 mm, while in formula fertilization by soil testing it was mainly distributed in the aggregates of 0.25-0.5 and 0-0.25 mm. [Conclusion] The study proved that for-mula fertilization by soil testing helped to reduce the risk of nitrogen pol ution and had huge effects on the chemical forms and distribution of nitrogen in different ag-gregates in dark brown soil.
基金The National Natural Science Foundation of China(No.51108081)
文摘To investigate migration and evolution rules of coarse aggregates in the static compaction process, an algorithm of generating digital coarse aggregates that can reflect real morphology（ such as shape, size and fracture surface） of aggregate particles, is represented by polyhedral particles based on the discrete element method（ DEM）. A digital specimen comprised of aggregates and air voids is developed. In addition,a static compaction model consisting of a digital specimen and three plates is constructed and a series of evaluation indices such as mean contact force σMCF, wall stress in direction of zcoordinate σWSZZ, porosity and coordination numbers are presented to investigate the motion rules of coarse aggregates at different compaction displacements of 7. 5, 15 and 30 mm. The three-dimensional static compaction model is also verified with laboratory measurements. The results indicate that the compaction displacements are positively related to σMCF and σWSZZ, which increase gradually with the increase in iterative steps. When the compaction proceeds, the digital specimen porosity decreases, but the coordination number increases. The variation ranges of these four indices are different at different compaction displacements. This study provides a method to analyze the compaction mechanism of particle materials such as asphalt mixture and graded broken stone.
