The surfaces of red soils have an apparent amphotenc character, carrying titratable acidity and titratable alkalinity simultaneously. The titratable acidity arises from deprotonation of hydroxyl groups of hydrous oxid...The surfaces of red soils have an apparent amphotenc character, carrying titratable acidity and titratable alkalinity simultaneously. The titratable acidity arises from deprotonation of hydroxyl groups of hydrous oxide-type surfaces and dissociation of weak-acid functional groups of soil organic matter, while the titratable alkalinity is derived from release of hydroxyl groups of hydrous oxide-type surfaces. The titratable acidity and titratable alkalinity mainly depended on the composition and content of iron and aluminum oxides in the soils. The results showed that the titratable acidity and titratable alkalinity were in significantly positive correlation not only with the content of amorphous aluminum oxide(Alo) and iron oxide(Feo) extracted with acid ammonium oxalate solution, free iron ox-ide(Fed) extracted with sodium dithionite-citrate-bicarbonate (DCB) and clays, but also with the zero point of charge (ZPC) of the samples. Organic matter made an important contribution to the titratable acidity. The titratable alkalinity was closely correlated with the amount of fluoride ions adsorbed. The titratable acidity and titratable alkalinity of red soils were influenced by parent materials, being in the order of red soil derived from basalt > that from tuff > that from granite. The titratable acidity and titratable alkalinity were closely related with origination of the variable charges of red soils, and to a certain extent were responsible for variable negative and positive charges of the soils.展开更多
The necessity to saline and sodic waters is sometimes used for irrigating agricultural activities under certain circumstances, but it is important to note that the use of these waters comes with specific consideration...The necessity to saline and sodic waters is sometimes used for irrigating agricultural activities under certain circumstances, but it is important to note that the use of these waters comes with specific considerations and limitations. One way to decrease undesirable effects of sodic waters on the physical and chemical properties of soils is to apply organic and chemical amendments within the soil. This study aimed to assess the effectiveness of saline water on soil acidity, alkalinity and nutrients leaching in sandy loamy soil at Bella flower farm, in Rwamagana District, Rwanda. The water used was from the Muhazi Lake which is classified as Class I (Saline water quality). Column leaching experiments using treated soils were then conducted under saturated conditions. The soil under experimental was first analyzed for its textural classification, soil properties and is classified as sandy loamy soil. The t-test was taken at 1%, 5% and 10% levels of statistical significance compared to control soil. The results indicated that the application of saline water to soils caused an increase in some soil nutrients like increase of Phosphorus (P), Potassium (K<sup>+</sup>), Magnesium (Mg2<sup>+</sup>), Sulphur (S), CN ratio and Sodium (Na<sup>+</sup>) and decreased soil texture, physical and chemical properties and remained soil nutrients. Consequently, the intensive addition of saline water leachates to soil in PVC pipes led to decreased of soil EC through leaching and a raiser Soluble Sodium Percentage (SSP). The rate of saline water application affected the increase accumulation of SAR and Na% in the top soil layers. The study indicated that saline water is an inefficient amendment for sandy soil with saline water irrigation. The study recommends further studies with similar topic with saline water irrigation, as it accentuated the alkalinity levels.展开更多
This investigation was conducted by using alkaline slag and crop straw biochars to reduce acidity of an acidic Ultisol through incubation and pot experiments with lime as a comparison. The soil was amended with differ...This investigation was conducted by using alkaline slag and crop straw biochars to reduce acidity of an acidic Ultisol through incubation and pot experiments with lime as a comparison. The soil was amended with different liming materials: lime(1 g kg-1),alkaline slag(2 and 4 g kg-1), peanut straw biochar(10 and 20 g kg-1), canola straw biochar(10 and 20 g kg-1) and combinations of alkaline slag(2 g kg-1) and biochars(10 g kg-1) in the incubation study. A pot experiment was also conducted to observe the soybean growth responses to the above treatments. The results showed that all the liming materials increased soil p H and decreased soil exchangeable acidity. The higher the rates of alkaline slag, biochars, and alkaline slag combined with biochars, the greater the increase in soil p H and the reduction in soil exchangeable acidity. All the amendments increased the levels of one or more soil exchangeable base cations. The lime treatment increased soil exchangeable Ca2+, the alkaline slag treatment increased exchangeable Ca2+and Mg2+levels, and the biochars and combined applications of alkaline slag with biochars increased soil exchangeable Ca2+, Mg2+and K+and soil available P. The amendments enhanced the uptake of one or more nutrients of N, P, K, Ca and Mg by soybean in the pot experiment. Of the different amendments, the combined application of alkaline slag with crop straw biochars was the best choice for increasing base saturation and reducing soil acidity of the acidic Ultisol. The combined application of alkaline slag with biochars led to the greatest reduction in soil acidity, increased soil Ca, Mg, K and P levels, and enhanced the uptake of Ca, Mg, K and P by soybean plants.展开更多
A pot experiment was catried out to study alleviation of soil acidity and Al toxicity by applying analkaline-stabilised sewage sludge product (biosolids) to an acid clay sandy loam (pH 5.7) and a strongly acidsandy lo...A pot experiment was catried out to study alleviation of soil acidity and Al toxicity by applying analkaline-stabilised sewage sludge product (biosolids) to an acid clay sandy loam (pH 5.7) and a strongly acidsandy loam (pH 4.5). Barley (Hondeum vulgare L. cv. Forrester) was used as a test crop and was grownin the sewage sludge-amended (33.5 t sludge DM ha-1) and unamended soils. The results showed that thealka1ine biosloids increased soil pH from 5.7 to 6.9 for the clay sandy loam and from 4.5 to 6.0 for the sandyloam. The sludge product decreased KCl-extractable Al from 0.1 to 0.0 cmol kg-1 for the former soil andfrom 4.0 to 0.1 cmol kg-1 for the latter soil. As a result, barley plants grew much better and grain yieldincreased greatly in the amended treatments compared with the unamended controls. These observationsindicate that alkaline-stabilised biosolids can be used as a liming material for remedying Al phytotoxicity instrongly acid soils by increasing soil pH and lowering Al bioavailability.展开更多
Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a collector.Flotation experiments showed that MFA produced a stronger in...Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a collector.Flotation experiments showed that MFA produced a stronger inhibition effect on pyrite than on chalcopyrite.The separation of chalcopyrite from pyrite was realized by introducing 150 mg/L MFA at a pulp pH of approximately 8.0.The copper grade,copper recovery,and separation efficiency were 28.03%,84.79%,and 71.66%,respectively.Surface adsorption tests,zeta potential determinations,and localized electrochemical impedance spectroscopy tests showed that more MFA adsorbed on pyrite than on chalcopyrite,which weakened the subsequent interactions between pyrite and the collector.Atomic force microscope imaging further confirmed the adsorption of MFA on pyrite,and X-ray photoelectron spectroscopy results indicated that hydrophilic Fe-based species on the pyrite surfaces increased after exposure of pyrite to MFA,thereby decreasing the floatability of pyrite.展开更多
Chalcopyrite is the main Cu-containing mineral and cannot be separated well from pyrite using traditional xanthate collectors with large amounts of lime depressant, resulting in difficulties of the tailing treatment a...Chalcopyrite is the main Cu-containing mineral and cannot be separated well from pyrite using traditional xanthate collectors with large amounts of lime depressant, resulting in difficulties of the tailing treatment and associated precious metals recovery. Therefore, in this study, the green and odourless ethylenediamine tetramethylenephosphonic acid(EDTMPA) was introduced as a novel chalcopyrite collector. Flotation results from the binary mineral mixture and real ore demonstrated that EDTMPA could realize the selective separation of chalcopyrite from pyrite relative to ethyl xanthate(EX) without any depressants within the wide p H range of 6.0–11.0, and might replace the traditional high-alkaline lime process. Electrochemical and Fourier transform infrared spectra measurements indicated that the difference in adsorption performance of EDTMPA on chalcopyrite and pyrite was larger than that of EX, suggesting a better selectivity for EDTMPA. Density functional theory calculations demonstrated that there were stronger chemical bonds between P—O groups of EDTMPA and the Fe/Cu atoms on chalcopyrite in the form of a stable six-membered ring. Crystal chemistry calculations further revealed that the activity of metal atoms of chalcopyrite was higher than that of pyrite. Therefore, these basic theoretical results and practical application provide a guidance for the industrial application of EDTMPA in chalcopyrite flotation.展开更多
Thermodynamic modeling is still themostwidely usedmethod to characterize aerosol acidity,a critical physicochemical property of atmospheric aerosols.However,it remains unclear whether gas-aerosol partitioning should b...Thermodynamic modeling is still themostwidely usedmethod to characterize aerosol acidity,a critical physicochemical property of atmospheric aerosols.However,it remains unclear whether gas-aerosol partitioning should be incorporated when thermodynamicmodels are employed to estimate the acidity of coarse particles.In this work,field measurements were conducted at a coastal city in northern China across three seasons,and covered wide ranges of temperature,relative humidity and NH_(3) concentrations.We examined the performance of different modes of ISORROPIA-II(a widely used aerosol thermodynamic model)in estimating aerosol acidity of coarse and fine particles.The M0 mode,which incorporates gas-phase data and runs the model in the forward mode,provided reasonable estimation of aerosol acidity for coarse and fine particles.Compared to M0,the M1 mode,which runs the model in the forward mode but does not include gas-phase data,may capture the general trend of aerosol acidity but underestimates pH for both coarse and fine particles;M2,which runs the model in the reverse mode,results in large errors in estimated aerosol pH for both coarse and fine particles and should not be used for aerosol acidity calculations.However,M1 significantly underestimates liquid water contents for both fine and coarse particles,while M2 provides reliable estimation of liquid water contents.In summary,our work highlights the importance of incorporating gas-aerosol partitioning when estimating coarse particle acidity,and thus may help improve our understanding of acidity of coarse particles.展开更多
Nitrate renoxification significantly influences atmospheric nitrogen cycling and global OH budgets.Although numerous nitrite acid(HONO)formation pathways from nitrate photolysis have been widely reported,the influence...Nitrate renoxification significantly influences atmospheric nitrogen cycling and global OH budgets.Although numerous nitrite acid(HONO)formation pathways from nitrate photolysis have been widely reported,the influence of various environmental factors and aerosol properties on reactive nitrogen production remains largely unclear.In this work,we employed NaNO_(3)/humic acid(HA)as a model nitrate photosensitization system to investigate the crucial roles of aerosol acidity,organic fraction,and dissolved oxygen in the production of HONO,NO_(2),and NO_(2)^(-).The presence of HA at 10 mg/L resulted in a remarkable increase in HONO production rates by approximately 2–3 times and NO_(2)^(-) concentration by 3–6 times across a pH range of 5.2 to 2.0.Meanwhile,the molar fraction of gaseous HONO in total N(Ⅲ)production increased from4%to 69%as bulk-phase pH decreased from 5.2 to 2.0.The higher organic fraction(i.e.,20 and 50 mg/L HA concentration)instead inhibited HONO and NO_(2) release.The presence of dissolved oxygen was found to be adverse for reactive nitrogen production.This suggests that the HA photosensitizer promoted the secondary conversion of NO_(2) to HONO mainly via reduced ketyl radical intermediates,while superoxide radical formation might exert a negative effect.Our findings provide comprehensive insights into reactive nitrogen production from photosensitized nitrate photolysis mediated by various external and internal factors,potentially accounting for discrepancies between field observations and model simulations.展开更多
Continuous-flow upgrading of pentaerythritol synthesis technology via base-catalyzed aldol and Cannizzaro reactions of formaldehyde and acetaldehyde faces the challenge of effectively controlling the critical side rea...Continuous-flow upgrading of pentaerythritol synthesis technology via base-catalyzed aldol and Cannizzaro reactions of formaldehyde and acetaldehyde faces the challenge of effectively controlling the critical side reaction of hydroxymethyl acetaldehyde(HA)to the acrolein intermediate.Here,we first identified the forms of industrial formaldehyde as methane diol that easily converts to the alkaline formaldehyde under alkaline(NaOH)environment.The carbonyl group of alkaline formaldehyde induces deprotonation of acetaldehyde instead of the recognized base-hydroxyl group-induced deprotonation,and it needs to overcome only 18.31 kcal·mol^(-1)(1 kcal=4.186 kJ)energy barrier to form key intermediates of HA.The sodium solvation cage formed by NaOH hexa-coordinated formaldehyde effectively inhibits the alkalinity,thus contributing to a high energy barrier(46.21 kcal·mol^(-1))to unwanted acrolein formation.In addition,the solvation cage gradually opens to increase the alkalinity with the consumption of formaldehyde,thus facilitating the subsequent Cannizzaro reaction(to overcome 11.77 kcal·mol^(-1)).In comparison,strong alkalinity promotes the formation of acrolein(36.65 kcal·mol^(-1))to initiate the acetal side reaction,while weak alkalinity reduces the possibility of the Cannizzaro reaction(to overcome 20.44 kcal·mol^(-1)).This theoretically reveals the importance of the segmented feeding of weak and strong bases to successively control the aldol reaction and Cannizzaro reaction,and the combination of Na_(2)CO_(3) or HCOONa with NaOH improves the pentaerythritol yield by 7%to 13%compared to that of NaOH alone(70%yield)within 1 min at a throughput of 155.7 ml·min^(-1).展开更多
High ammonia-nitrogen digestate has become a key bottleneck limiting the anaerobic digestion of organic solid waste.Vacuum ammonia stripping can simultaneously remove and recover ammonia nitrogen,which has attracted a...High ammonia-nitrogen digestate has become a key bottleneck limiting the anaerobic digestion of organic solid waste.Vacuum ammonia stripping can simultaneously remove and recover ammonia nitrogen,which has attracted a lot of attention in recent years.To investigate the parameter effects on the efficiency and mass transfer,five combination conditions(53℃ 15 kPa,60°C 20 kPa,65°C 25 kPa,72°C 35 kPa,and 81°C 50 kPa)were conducted for ammonia stripping of sludge digestate.The results showed that 80%of ammonia nitrogen was stripped in 45 min for all experimental groups,but the ammonia transfer coefficient varied under different conditions,which increased with the rising of boiling point temperature,and reached the maximum value(39.0 mm/hr)at 81°C 50 kPa.The ammonia nitrogen removal efficiency was more than 80%for 30 min vacuum stripping after adjusting the initial pH to above 9.5,and adjustment of the initial alkalinity also affects the pH value of liquid digestate.It was found that pH and alkalinity are the key factors influencing the ammonia nitrogen dissociation and removal efficiency,while temperature and vacuum mainly affect the ammonia nitrogen mass transfer and removal velocity.In terms of the mechanism of vacuum ammonia stripping,it underwent alkalinity destruction,pH enhancement,ammonia nitrogen dissociation,and free ammonia removal.In this study,two-stage experiments of alkalinity destruction and ammonia removal were also carried out,which showed that the two-stage configuration was beneficial for ammonia removal.It provides a theoretical basis and practical technology for the vacuum ammonia stripping from liquid digestate of organic solid waste.展开更多
The presence of residual alkaline compounds in the ultrahigh-nickel layered oxide cathodes(LiNi_(x)Co_(y)Mn_(1−x−y)O_(2),x≥_(0.9))aggravates structural degradation,increases surface reactivity,and promotes slurry gel...The presence of residual alkaline compounds in the ultrahigh-nickel layered oxide cathodes(LiNi_(x)Co_(y)Mn_(1−x−y)O_(2),x≥_(0.9))aggravates structural degradation,increases surface reactivity,and promotes slurry gelation,leading to the capacity decay of batteries with these cathodes and complicating their manufacturing.Traditional approaches for addressing this issue,including direct removal,coverage,and utilization,are complex and require surface regeneration.Herein,we propose neutralizing residual alkaline compounds with 3-thiopheneboronic acid(3-TBA)to improve the performance of LiNi_(0.9)5Co_(0.04)Mn_(0.01)O_(2)(NCM)cathode material,a facile strategy that does not require any post-treatment.The suggested reaction yields a uniform and thin organic-modified layer on the surface of the NCM cathode,improving its chemical stability toward the electrolyte,as demonstrated by multiple characterization methods.The modified NCM cathode exhibited impressive cyclic and rate performances,achieving a capacity retention of 83.34%after 200 cycles at 1.0 C and a specific capacity of 162.00 mAh·g^(−1) at 10.0 C.Most importantly,the proposed approach can efficiently suppress unfavorable phase transitions,severe electrolyte degradation,and CO_(2) gas evolution,improving the application potential of ultrahigh-nickel layered oxide cathode materials.展开更多
Electrocatalytic oxidation of surplus ethylene glycol(EG)to high-value glycolic acid(GA)represents a promising approach for sustainable resource utilization,though critical challenges persist in developing durable ele...Electrocatalytic oxidation of surplus ethylene glycol(EG)to high-value glycolic acid(GA)represents a promising approach for sustainable resource utilization,though critical challenges persist in developing durable electrocatalysts and achieving effective recovery of the free acid product from its salt derivatives in alkaline electrolytes.In this work,a PdNi/NF catalyst was rationally synthesized via a one-step electrodeposition method.Systematic characterization revealed that the electron transfer from Ni to Pd modulates *OH adsorption to accelerate EG oxidation reaction(EGOR)while preventing Pd deactivation through oxidation.The optimized system demonstrated exceptional alkaline performance with a glycolic acid Faraday efficiencyof 95%and a current density of 666 mA·cm^(-2).When implemented in an asymmetric EGOR||HER flowcell configuration where only the cathodic electrolyte contains alkaline,the system demonstrated exceptional operational stability by sustaining 70 mA·cm^(-2) current density at a low cell voltage of 0.9 V in neutral media for over 100 h,with product glycolic acid requiring no further acidification.This investigation provides a practical framework for designing efficientelectrocatalytic systems that simplifiesproduct separation steps.展开更多
Constructing new Brönsted acid sites within zeolitic materials holds paramount importance for the advancement of solid-acid catalysis.Zeo-type germanosilicates,a class of metallosilicates with a neutral framework...Constructing new Brönsted acid sites within zeolitic materials holds paramount importance for the advancement of solid-acid catalysis.Zeo-type germanosilicates,a class of metallosilicates with a neutral framework composed of tetravalent Ge and Si oxygen tetrahedrons,are conventionally considered not to generate Brönsted acid sites.Herein,we disclose an abnormal phenomenon with Ge-rich IWW-type germanosilicate(IWW-A)as an example that Ge-enriched germanosilicates are featured by mild Brönsted acidity.Using the art-of-state density functional theory calculation,19F magic angle spinning nuclear magnetic resonance,microcalorimetric and ammonia infrared mass spectrometry-temperature-programmed desorption characterizations,the nature of germanosilicate's Brönsted acidity has been demonstrated to be closely related to the neighboring framework Ge-hydroxyl pairs.Besides,the contribution of Ge-OH groups to Brönsted acidity and the role of Ge-pair structure for maintaining mild acid strength have been elucidated.In catalytic cracking of n-hexane and methanol-to-olefins reaction,the IWW-A germanosilicate exhibit high light olefins selectivity,good recyclability and low carbon deposition,outperforming the benchmark zeolite catalyst,ZSM-5 aluminosilicate.展开更多
This study explores the adaptation of microbial enzymatic techniques,which were originally developed to eliminate amino impurities in alcoholic beverages,for stabilizing strongly alkaline sodium-based dispersive soils...This study explores the adaptation of microbial enzymatic techniques,which were originally developed to eliminate amino impurities in alcoholic beverages,for stabilizing strongly alkaline sodium-based dispersive soils from check dams.Employing acid urease from Lactobacillus reuteri(L.reuteri)and a control group using soybean-derived urease,this research aimed to modify soil alkalinity through biomineralization.Ultraviolet(UV)mutagenesis optimized L.reuteri strains for biomass and activity.Solution experiments were conducted to assess the effects of pH,temperature,and storage duration on urease activity and to evaluate the calcium carbonate production and crystal morphology of the two ureases under varying calcium ion concentrations.Dispersivity identificationtests and tensile strength evaluations were conducted to analyze the disparities in the modifieddispersive soil treated with the two types of ureases.The results showed that soybean urease should be stored under low-temperature conditions and a neutral pH,whereas acid urease from L.reuteri can be stored at room temperature across a range of pH levels.Both urease treatments effectively reduced soil dispersivity and improved tensile strength significantly(up to 94%and 177%,respectively),with acid urease from L.reuteri resulting in superior soil strengthening and ammonia regulation.These findingssuggest that treating alkaline dispersive soils with acid urease is an efficientand eco-friendly method.展开更多
Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,includi...Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,including cerebrospinal fluid,varies significantly(Figure 1Α;Yung et al.,2014).LPA actually corresponds to a variety of lipid species that include different stereoisomers with either saturated or unsaturated fatty acids bearing likely differentiated biological activities(Figure 1Α;Yung et al.,2014;Hernández-Araiza et al.,2018).展开更多
Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electro...Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts.展开更多
Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’...Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’s disease.In this review,we summarize the changes in short-chain fatty acid levels and the abundance of short-chain fatty acid-producing bacteria in various samples from patients with Parkinson’s disease,highlighting the critical role of gut homeostasis imbalance in the pathogenesis and progression of the disease.Focusing on the nervous system,we discuss the molecular mechanisms by which short-chain fatty acids influence the homeostasis of both the enteric nervous system and the central nervous system.We identify key processes,including the activation of G protein-coupled receptors and the inhibition of histone deacetylases by short-chain fatty acids.Importantly,structural or functional disruptions in the enteric nervous system mediated by these fatty acids may lead to abnormalα-synuclein expression and gastrointestinal dysmotility,which could serve as an initiating event in Parkinson’s disease.Furthermore,we propose that short-chain fatty acids help establish communication between the enteric nervous system and the central nervous system via the vagal nerve,immune circulation,and endocrine signaling.This communication may shed light on their potential role in the transmission ofα-synuclein from the gut to the brain.Finally,we elucidate novel treatment strategies for Parkinson’s disease that target short-chain fatty acids and examine the challenges associated with translating short-chain fatty acid-based therapies into clinical practice.In conclusion,this review emphasizes the pivotal role of short-chain fatty acids in regulating gut-brain axis integrity and their significance in the pathogenesis of Parkinson’s disease from the perspective of the nervous system.Moreover,it highlights the potential value of short-chain fatty acids in early intervention for Parkinson’s disease.Future research into the molecular mechanisms of short-chain fatty acids and their synergistic interactions with other gut metabolites is likely to advance the clinical translation of innovative short-chain fatty acid-based therapies for Parkinson’s disease.展开更多
Objective:To investigate effect of oleanolic acid(OA)on atherosclerosis and its related mechanisms.Methods:Human umbilical vein endothelial cells(HUVECs)were injured by oxidized low-density lipoprotein for 24 h and tr...Objective:To investigate effect of oleanolic acid(OA)on atherosclerosis and its related mechanisms.Methods:Human umbilical vein endothelial cells(HUVECs)were injured by oxidized low-density lipoprotein for 24 h and treated with OA,and the levels of cell proliferation,migration,adhesion,and apoptosis were evaluated by BrdU staining,scratch healing assay,monocyte-endothelial cell adhesion assay and flow cytometry.The mice were fed with a high-fat diet to induce an atherosclerosis model,and treated with OA by gastric gavage.The mice were divided into the control group,the model group,and the OA administration group.The blood lipid and plaque formation in mice were detected.In addition,oxidative stress and mitochondrial structure and function changes in cells and mice were evaluated by transmission electron microscopy,JC-1 fluorescent probe,and Western blotting assays.The expression levels of proteins in the AMPK/Drp1 pathway were examined through Western blot.Results:OA markedly increased cell viability and migration rate of HUVECs,and decreased the adhesion rate of THP-1 cells and the apoptosis rate.OA significantly reduced serum lipid levels,such as total cholesterol and triglyceride,in mice and inhibited plaque formation in the aorta.OA also significantly increased the content of superoxide dismutase and catalase,alleviated mitochondrial damage,such as mitochondrial swelling and mitochondrial cristae reduction,reduced the number of mitochondria,increased adenosine triphosphate content,and significantly reduced p-Drp1(Ser616)/Drp1,MFF and FIS1 levels,increased p-AMPK/AMPK levels,activated AMPK,and then regulated DRP1 activity.Conclusions:OA activates AMPK,which in turn regulates the activity of DRP1 to restore normal mitochondrial dynamics and reduce atherosclerosis.展开更多
Microglia are the resident macrophages of the central nervous system.They act as the first line of defense against pathogens and play essential roles in neuroinflammation and tissue repair after brain insult or in neu...Microglia are the resident macrophages of the central nervous system.They act as the first line of defense against pathogens and play essential roles in neuroinflammation and tissue repair after brain insult or in neurodegenerative and demyelinating diseases(Borst et al.,2021).Together with infiltrating monocyte-derived macrophages,microglia also play a critical role for brain tumor development,since immunosuppressive interactions between tumor cells and tumor-associated microglia and macrophages(TAM)are linked to malignant progression.This mechanism is of particular relevance in glioblastoma(GB),the deadliest form of brain cancer with a median overall survival of less than 15 months(Khan et al.,2023).Therefore,targeting microglia and macrophage activation is a promising strategy for therapeutic interference in brain disease.展开更多
The early developmental period is a critical window during which brain cells mature and contribute to both brain development and later life functions.Gamma-aminobutyric acid(GABA),recognized as a major neurotransmitte...The early developmental period is a critical window during which brain cells mature and contribute to both brain development and later life functions.Gamma-aminobutyric acid(GABA),recognized as a major neurotransmitter,plays a crucial role in coordinating synapse formation,neuronal proliferation,and migration during this time.展开更多
基金Project supported by the National Natural Science Foundation of China.
文摘The surfaces of red soils have an apparent amphotenc character, carrying titratable acidity and titratable alkalinity simultaneously. The titratable acidity arises from deprotonation of hydroxyl groups of hydrous oxide-type surfaces and dissociation of weak-acid functional groups of soil organic matter, while the titratable alkalinity is derived from release of hydroxyl groups of hydrous oxide-type surfaces. The titratable acidity and titratable alkalinity mainly depended on the composition and content of iron and aluminum oxides in the soils. The results showed that the titratable acidity and titratable alkalinity were in significantly positive correlation not only with the content of amorphous aluminum oxide(Alo) and iron oxide(Feo) extracted with acid ammonium oxalate solution, free iron ox-ide(Fed) extracted with sodium dithionite-citrate-bicarbonate (DCB) and clays, but also with the zero point of charge (ZPC) of the samples. Organic matter made an important contribution to the titratable acidity. The titratable alkalinity was closely correlated with the amount of fluoride ions adsorbed. The titratable acidity and titratable alkalinity of red soils were influenced by parent materials, being in the order of red soil derived from basalt > that from tuff > that from granite. The titratable acidity and titratable alkalinity were closely related with origination of the variable charges of red soils, and to a certain extent were responsible for variable negative and positive charges of the soils.
文摘The necessity to saline and sodic waters is sometimes used for irrigating agricultural activities under certain circumstances, but it is important to note that the use of these waters comes with specific considerations and limitations. One way to decrease undesirable effects of sodic waters on the physical and chemical properties of soils is to apply organic and chemical amendments within the soil. This study aimed to assess the effectiveness of saline water on soil acidity, alkalinity and nutrients leaching in sandy loamy soil at Bella flower farm, in Rwamagana District, Rwanda. The water used was from the Muhazi Lake which is classified as Class I (Saline water quality). Column leaching experiments using treated soils were then conducted under saturated conditions. The soil under experimental was first analyzed for its textural classification, soil properties and is classified as sandy loamy soil. The t-test was taken at 1%, 5% and 10% levels of statistical significance compared to control soil. The results indicated that the application of saline water to soils caused an increase in some soil nutrients like increase of Phosphorus (P), Potassium (K<sup>+</sup>), Magnesium (Mg2<sup>+</sup>), Sulphur (S), CN ratio and Sodium (Na<sup>+</sup>) and decreased soil texture, physical and chemical properties and remained soil nutrients. Consequently, the intensive addition of saline water leachates to soil in PVC pipes led to decreased of soil EC through leaching and a raiser Soluble Sodium Percentage (SSP). The rate of saline water application affected the increase accumulation of SAR and Na% in the top soil layers. The study indicated that saline water is an inefficient amendment for sandy soil with saline water irrigation. The study recommends further studies with similar topic with saline water irrigation, as it accentuated the alkalinity levels.
基金Supported by the National Basic Research Program(973 Program)of China(No.2014CB441003)the National Natural Science Foundation of China(No.41271010)
文摘This investigation was conducted by using alkaline slag and crop straw biochars to reduce acidity of an acidic Ultisol through incubation and pot experiments with lime as a comparison. The soil was amended with different liming materials: lime(1 g kg-1),alkaline slag(2 and 4 g kg-1), peanut straw biochar(10 and 20 g kg-1), canola straw biochar(10 and 20 g kg-1) and combinations of alkaline slag(2 g kg-1) and biochars(10 g kg-1) in the incubation study. A pot experiment was also conducted to observe the soybean growth responses to the above treatments. The results showed that all the liming materials increased soil p H and decreased soil exchangeable acidity. The higher the rates of alkaline slag, biochars, and alkaline slag combined with biochars, the greater the increase in soil p H and the reduction in soil exchangeable acidity. All the amendments increased the levels of one or more soil exchangeable base cations. The lime treatment increased soil exchangeable Ca2+, the alkaline slag treatment increased exchangeable Ca2+and Mg2+levels, and the biochars and combined applications of alkaline slag with biochars increased soil exchangeable Ca2+, Mg2+and K+and soil available P. The amendments enhanced the uptake of one or more nutrients of N, P, K, Ca and Mg by soybean in the pot experiment. Of the different amendments, the combined application of alkaline slag with crop straw biochars was the best choice for increasing base saturation and reducing soil acidity of the acidic Ultisol. The combined application of alkaline slag with biochars led to the greatest reduction in soil acidity, increased soil Ca, Mg, K and P levels, and enhanced the uptake of Ca, Mg, K and P by soybean plants.
基金National Natural Science Foundation of China(Nos.49831070 and 40125005)theNational Key Basic Research Support Foundation of China(No.G1999011807) the Jiangsu Provincial Foundation for Young Scientists(No.BQ98050).
文摘A pot experiment was catried out to study alleviation of soil acidity and Al toxicity by applying analkaline-stabilised sewage sludge product (biosolids) to an acid clay sandy loam (pH 5.7) and a strongly acidsandy loam (pH 4.5). Barley (Hondeum vulgare L. cv. Forrester) was used as a test crop and was grownin the sewage sludge-amended (33.5 t sludge DM ha-1) and unamended soils. The results showed that thealka1ine biosloids increased soil pH from 5.7 to 6.9 for the clay sandy loam and from 4.5 to 6.0 for the sandyloam. The sludge product decreased KCl-extractable Al from 0.1 to 0.0 cmol kg-1 for the former soil andfrom 4.0 to 0.1 cmol kg-1 for the latter soil. As a result, barley plants grew much better and grain yieldincreased greatly in the amended treatments compared with the unamended controls. These observationsindicate that alkaline-stabilised biosolids can be used as a liming material for remedying Al phytotoxicity instrongly acid soils by increasing soil pH and lowering Al bioavailability.
基金supported by Fundamental Research Projects of Yunnan Province,China(Nos.202101BE070001-009,202301AU070189).
文摘Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a collector.Flotation experiments showed that MFA produced a stronger inhibition effect on pyrite than on chalcopyrite.The separation of chalcopyrite from pyrite was realized by introducing 150 mg/L MFA at a pulp pH of approximately 8.0.The copper grade,copper recovery,and separation efficiency were 28.03%,84.79%,and 71.66%,respectively.Surface adsorption tests,zeta potential determinations,and localized electrochemical impedance spectroscopy tests showed that more MFA adsorbed on pyrite than on chalcopyrite,which weakened the subsequent interactions between pyrite and the collector.Atomic force microscope imaging further confirmed the adsorption of MFA on pyrite,and X-ray photoelectron spectroscopy results indicated that hydrophilic Fe-based species on the pyrite surfaces increased after exposure of pyrite to MFA,thereby decreasing the floatability of pyrite.
基金financial supports from the Key Program for International S&T Cooperation Projects of China (No. 2021YFE0106800)the National Natural Science Foundation of China (No. U2067201)+3 种基金the Leading Talents of S & T Innovation of Hunan Province, China (No. 2021RC4002)the Science Fund for Distinguished Young Scholars of Hunan Province, China (No. 2020JJ2044)the Key Research and Development Program of Hunan Province, China (No. 2021SK2043)the National 111 Project, China (No. B14034)。
文摘Chalcopyrite is the main Cu-containing mineral and cannot be separated well from pyrite using traditional xanthate collectors with large amounts of lime depressant, resulting in difficulties of the tailing treatment and associated precious metals recovery. Therefore, in this study, the green and odourless ethylenediamine tetramethylenephosphonic acid(EDTMPA) was introduced as a novel chalcopyrite collector. Flotation results from the binary mineral mixture and real ore demonstrated that EDTMPA could realize the selective separation of chalcopyrite from pyrite relative to ethyl xanthate(EX) without any depressants within the wide p H range of 6.0–11.0, and might replace the traditional high-alkaline lime process. Electrochemical and Fourier transform infrared spectra measurements indicated that the difference in adsorption performance of EDTMPA on chalcopyrite and pyrite was larger than that of EX, suggesting a better selectivity for EDTMPA. Density functional theory calculations demonstrated that there were stronger chemical bonds between P—O groups of EDTMPA and the Fe/Cu atoms on chalcopyrite in the form of a stable six-membered ring. Crystal chemistry calculations further revealed that the activity of metal atoms of chalcopyrite was higher than that of pyrite. Therefore, these basic theoretical results and practical application provide a guidance for the industrial application of EDTMPA in chalcopyrite flotation.
基金supported by the National Natural Science Foundation of China (Nos.42022050 and 42277088)the Guangdong Basic and Applied Basic Research Fund Committee (Nos.2021A1515011248 and 2023A1515012010)the Guangdong Foundation for the Program of Science and Technology Research (No.2020B1212060053).
文摘Thermodynamic modeling is still themostwidely usedmethod to characterize aerosol acidity,a critical physicochemical property of atmospheric aerosols.However,it remains unclear whether gas-aerosol partitioning should be incorporated when thermodynamicmodels are employed to estimate the acidity of coarse particles.In this work,field measurements were conducted at a coastal city in northern China across three seasons,and covered wide ranges of temperature,relative humidity and NH_(3) concentrations.We examined the performance of different modes of ISORROPIA-II(a widely used aerosol thermodynamic model)in estimating aerosol acidity of coarse and fine particles.The M0 mode,which incorporates gas-phase data and runs the model in the forward mode,provided reasonable estimation of aerosol acidity for coarse and fine particles.Compared to M0,the M1 mode,which runs the model in the forward mode but does not include gas-phase data,may capture the general trend of aerosol acidity but underestimates pH for both coarse and fine particles;M2,which runs the model in the reverse mode,results in large errors in estimated aerosol pH for both coarse and fine particles and should not be used for aerosol acidity calculations.However,M1 significantly underestimates liquid water contents for both fine and coarse particles,while M2 provides reliable estimation of liquid water contents.In summary,our work highlights the importance of incorporating gas-aerosol partitioning when estimating coarse particle acidity,and thus may help improve our understanding of acidity of coarse particles.
基金supported by the National Key R&D Program of China(No.2022YFC3701102)the National Natural Science Foundation of China(Nos.22376029,22176038,91744205 and 21777025)the Natural Science Foundation of Shanghai City(No.22ZR1404700).
文摘Nitrate renoxification significantly influences atmospheric nitrogen cycling and global OH budgets.Although numerous nitrite acid(HONO)formation pathways from nitrate photolysis have been widely reported,the influence of various environmental factors and aerosol properties on reactive nitrogen production remains largely unclear.In this work,we employed NaNO_(3)/humic acid(HA)as a model nitrate photosensitization system to investigate the crucial roles of aerosol acidity,organic fraction,and dissolved oxygen in the production of HONO,NO_(2),and NO_(2)^(-).The presence of HA at 10 mg/L resulted in a remarkable increase in HONO production rates by approximately 2–3 times and NO_(2)^(-) concentration by 3–6 times across a pH range of 5.2 to 2.0.Meanwhile,the molar fraction of gaseous HONO in total N(Ⅲ)production increased from4%to 69%as bulk-phase pH decreased from 5.2 to 2.0.The higher organic fraction(i.e.,20 and 50 mg/L HA concentration)instead inhibited HONO and NO_(2) release.The presence of dissolved oxygen was found to be adverse for reactive nitrogen production.This suggests that the HA photosensitizer promoted the secondary conversion of NO_(2) to HONO mainly via reduced ketyl radical intermediates,while superoxide radical formation might exert a negative effect.Our findings provide comprehensive insights into reactive nitrogen production from photosensitized nitrate photolysis mediated by various external and internal factors,potentially accounting for discrepancies between field observations and model simulations.
基金funded by the National Natural Science Foundation of China(22478632)Key Scientific and Technological Project of Henan Province(242102321032).
文摘Continuous-flow upgrading of pentaerythritol synthesis technology via base-catalyzed aldol and Cannizzaro reactions of formaldehyde and acetaldehyde faces the challenge of effectively controlling the critical side reaction of hydroxymethyl acetaldehyde(HA)to the acrolein intermediate.Here,we first identified the forms of industrial formaldehyde as methane diol that easily converts to the alkaline formaldehyde under alkaline(NaOH)environment.The carbonyl group of alkaline formaldehyde induces deprotonation of acetaldehyde instead of the recognized base-hydroxyl group-induced deprotonation,and it needs to overcome only 18.31 kcal·mol^(-1)(1 kcal=4.186 kJ)energy barrier to form key intermediates of HA.The sodium solvation cage formed by NaOH hexa-coordinated formaldehyde effectively inhibits the alkalinity,thus contributing to a high energy barrier(46.21 kcal·mol^(-1))to unwanted acrolein formation.In addition,the solvation cage gradually opens to increase the alkalinity with the consumption of formaldehyde,thus facilitating the subsequent Cannizzaro reaction(to overcome 11.77 kcal·mol^(-1)).In comparison,strong alkalinity promotes the formation of acrolein(36.65 kcal·mol^(-1))to initiate the acetal side reaction,while weak alkalinity reduces the possibility of the Cannizzaro reaction(to overcome 20.44 kcal·mol^(-1)).This theoretically reveals the importance of the segmented feeding of weak and strong bases to successively control the aldol reaction and Cannizzaro reaction,and the combination of Na_(2)CO_(3) or HCOONa with NaOH improves the pentaerythritol yield by 7%to 13%compared to that of NaOH alone(70%yield)within 1 min at a throughput of 155.7 ml·min^(-1).
基金supported by the National Key Research and Development Program of China(No.2020YFC1908702)the National Natural Science Foundation of China(No.52131002)+1 种基金the Science and Technology Commission of Shanghai Municipality(No.22dz1209200)China Three Gorges Corporation(No.202403018).
文摘High ammonia-nitrogen digestate has become a key bottleneck limiting the anaerobic digestion of organic solid waste.Vacuum ammonia stripping can simultaneously remove and recover ammonia nitrogen,which has attracted a lot of attention in recent years.To investigate the parameter effects on the efficiency and mass transfer,five combination conditions(53℃ 15 kPa,60°C 20 kPa,65°C 25 kPa,72°C 35 kPa,and 81°C 50 kPa)were conducted for ammonia stripping of sludge digestate.The results showed that 80%of ammonia nitrogen was stripped in 45 min for all experimental groups,but the ammonia transfer coefficient varied under different conditions,which increased with the rising of boiling point temperature,and reached the maximum value(39.0 mm/hr)at 81°C 50 kPa.The ammonia nitrogen removal efficiency was more than 80%for 30 min vacuum stripping after adjusting the initial pH to above 9.5,and adjustment of the initial alkalinity also affects the pH value of liquid digestate.It was found that pH and alkalinity are the key factors influencing the ammonia nitrogen dissociation and removal efficiency,while temperature and vacuum mainly affect the ammonia nitrogen mass transfer and removal velocity.In terms of the mechanism of vacuum ammonia stripping,it underwent alkalinity destruction,pH enhancement,ammonia nitrogen dissociation,and free ammonia removal.In this study,two-stage experiments of alkalinity destruction and ammonia removal were also carried out,which showed that the two-stage configuration was beneficial for ammonia removal.It provides a theoretical basis and practical technology for the vacuum ammonia stripping from liquid digestate of organic solid waste.
基金the Yunnan Fundamental Research Projects(Grant Nos.202501AT070298,202401AU070163,and 202401AT070368)the National Natural Science Foundation of China(Grant No.52162030)+5 种基金the Yunnan Major Scientific and Technological Projects(Grant No.202202AG050003)the Yunnan Engineering Research Center Innovation Ability Construction and Enhancement Projects(Grant No.2023-XMDJ-00617107)the University Service Key Industry Project of Yunnan Province(Grant No.FWCY-ZD2024005)the Yunnan Thousand Talents Program for Young Talents(Grant No.KKS2202052001)the Scientific Research Foundation of Kunming University of Science and Technology(Grant No.20220122)the Analysis and Testing Foundation of Kunming University of Science and Technology(Grant No.2023T20220122).
文摘The presence of residual alkaline compounds in the ultrahigh-nickel layered oxide cathodes(LiNi_(x)Co_(y)Mn_(1−x−y)O_(2),x≥_(0.9))aggravates structural degradation,increases surface reactivity,and promotes slurry gelation,leading to the capacity decay of batteries with these cathodes and complicating their manufacturing.Traditional approaches for addressing this issue,including direct removal,coverage,and utilization,are complex and require surface regeneration.Herein,we propose neutralizing residual alkaline compounds with 3-thiopheneboronic acid(3-TBA)to improve the performance of LiNi_(0.9)5Co_(0.04)Mn_(0.01)O_(2)(NCM)cathode material,a facile strategy that does not require any post-treatment.The suggested reaction yields a uniform and thin organic-modified layer on the surface of the NCM cathode,improving its chemical stability toward the electrolyte,as demonstrated by multiple characterization methods.The modified NCM cathode exhibited impressive cyclic and rate performances,achieving a capacity retention of 83.34%after 200 cycles at 1.0 C and a specific capacity of 162.00 mAh·g^(−1) at 10.0 C.Most importantly,the proposed approach can efficiently suppress unfavorable phase transitions,severe electrolyte degradation,and CO_(2) gas evolution,improving the application potential of ultrahigh-nickel layered oxide cathode materials.
基金financially supported by the National Key Research and Development Program of China(2022YFA1504200)the National Natural Science Foundation of China(22178033 and 22090030)the Fundamental Research Funds for the Central Universities(2024CDJXY010).
文摘Electrocatalytic oxidation of surplus ethylene glycol(EG)to high-value glycolic acid(GA)represents a promising approach for sustainable resource utilization,though critical challenges persist in developing durable electrocatalysts and achieving effective recovery of the free acid product from its salt derivatives in alkaline electrolytes.In this work,a PdNi/NF catalyst was rationally synthesized via a one-step electrodeposition method.Systematic characterization revealed that the electron transfer from Ni to Pd modulates *OH adsorption to accelerate EG oxidation reaction(EGOR)while preventing Pd deactivation through oxidation.The optimized system demonstrated exceptional alkaline performance with a glycolic acid Faraday efficiencyof 95%and a current density of 666 mA·cm^(-2).When implemented in an asymmetric EGOR||HER flowcell configuration where only the cathodic electrolyte contains alkaline,the system demonstrated exceptional operational stability by sustaining 70 mA·cm^(-2) current density at a low cell voltage of 0.9 V in neutral media for over 100 h,with product glycolic acid requiring no further acidification.This investigation provides a practical framework for designing efficientelectrocatalytic systems that simplifiesproduct separation steps.
文摘Constructing new Brönsted acid sites within zeolitic materials holds paramount importance for the advancement of solid-acid catalysis.Zeo-type germanosilicates,a class of metallosilicates with a neutral framework composed of tetravalent Ge and Si oxygen tetrahedrons,are conventionally considered not to generate Brönsted acid sites.Herein,we disclose an abnormal phenomenon with Ge-rich IWW-type germanosilicate(IWW-A)as an example that Ge-enriched germanosilicates are featured by mild Brönsted acidity.Using the art-of-state density functional theory calculation,19F magic angle spinning nuclear magnetic resonance,microcalorimetric and ammonia infrared mass spectrometry-temperature-programmed desorption characterizations,the nature of germanosilicate's Brönsted acidity has been demonstrated to be closely related to the neighboring framework Ge-hydroxyl pairs.Besides,the contribution of Ge-OH groups to Brönsted acidity and the role of Ge-pair structure for maintaining mild acid strength have been elucidated.In catalytic cracking of n-hexane and methanol-to-olefins reaction,the IWW-A germanosilicate exhibit high light olefins selectivity,good recyclability and low carbon deposition,outperforming the benchmark zeolite catalyst,ZSM-5 aluminosilicate.
基金financiallysupported by the National Natural Science Foundation of China(Grant Nos.52079116,52108343,and 51579215).
文摘This study explores the adaptation of microbial enzymatic techniques,which were originally developed to eliminate amino impurities in alcoholic beverages,for stabilizing strongly alkaline sodium-based dispersive soils from check dams.Employing acid urease from Lactobacillus reuteri(L.reuteri)and a control group using soybean-derived urease,this research aimed to modify soil alkalinity through biomineralization.Ultraviolet(UV)mutagenesis optimized L.reuteri strains for biomass and activity.Solution experiments were conducted to assess the effects of pH,temperature,and storage duration on urease activity and to evaluate the calcium carbonate production and crystal morphology of the two ureases under varying calcium ion concentrations.Dispersivity identificationtests and tensile strength evaluations were conducted to analyze the disparities in the modifieddispersive soil treated with the two types of ureases.The results showed that soybean urease should be stored under low-temperature conditions and a neutral pH,whereas acid urease from L.reuteri can be stored at room temperature across a range of pH levels.Both urease treatments effectively reduced soil dispersivity and improved tensile strength significantly(up to 94%and 177%,respectively),with acid urease from L.reuteri resulting in superior soil strengthening and ammonia regulation.These findingssuggest that treating alkaline dispersive soils with acid urease is an efficientand eco-friendly method.
基金supported by the Hellenic Foundation for Research and Innovation,HFRI,“2nd Call for HFRI Research Projects to support Faculty Members&Researchers”Project 02667 to GL.
文摘Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,including cerebrospinal fluid,varies significantly(Figure 1Α;Yung et al.,2014).LPA actually corresponds to a variety of lipid species that include different stereoisomers with either saturated or unsaturated fatty acids bearing likely differentiated biological activities(Figure 1Α;Yung et al.,2014;Hernández-Araiza et al.,2018).
基金the financial support from the National Natural Science Foundation of China(52172110,52472231,52311530113)Shanghai"Science and Technology Innovation Action Plan"intergovernmental international science and technology cooperation project(23520710600)+1 种基金Science and Technology Commission of Shanghai Municipality(22DZ1205600)the Central Guidance on Science and Technology Development Fund of Zhejiang Province(2024ZY01011)。
文摘Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts.
基金supported by the National Key R&D Program of China,No.2021YFC2501200(to PC).
文摘Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’s disease.In this review,we summarize the changes in short-chain fatty acid levels and the abundance of short-chain fatty acid-producing bacteria in various samples from patients with Parkinson’s disease,highlighting the critical role of gut homeostasis imbalance in the pathogenesis and progression of the disease.Focusing on the nervous system,we discuss the molecular mechanisms by which short-chain fatty acids influence the homeostasis of both the enteric nervous system and the central nervous system.We identify key processes,including the activation of G protein-coupled receptors and the inhibition of histone deacetylases by short-chain fatty acids.Importantly,structural or functional disruptions in the enteric nervous system mediated by these fatty acids may lead to abnormalα-synuclein expression and gastrointestinal dysmotility,which could serve as an initiating event in Parkinson’s disease.Furthermore,we propose that short-chain fatty acids help establish communication between the enteric nervous system and the central nervous system via the vagal nerve,immune circulation,and endocrine signaling.This communication may shed light on their potential role in the transmission ofα-synuclein from the gut to the brain.Finally,we elucidate novel treatment strategies for Parkinson’s disease that target short-chain fatty acids and examine the challenges associated with translating short-chain fatty acid-based therapies into clinical practice.In conclusion,this review emphasizes the pivotal role of short-chain fatty acids in regulating gut-brain axis integrity and their significance in the pathogenesis of Parkinson’s disease from the perspective of the nervous system.Moreover,it highlights the potential value of short-chain fatty acids in early intervention for Parkinson’s disease.Future research into the molecular mechanisms of short-chain fatty acids and their synergistic interactions with other gut metabolites is likely to advance the clinical translation of innovative short-chain fatty acid-based therapies for Parkinson’s disease.
文摘Objective:To investigate effect of oleanolic acid(OA)on atherosclerosis and its related mechanisms.Methods:Human umbilical vein endothelial cells(HUVECs)were injured by oxidized low-density lipoprotein for 24 h and treated with OA,and the levels of cell proliferation,migration,adhesion,and apoptosis were evaluated by BrdU staining,scratch healing assay,monocyte-endothelial cell adhesion assay and flow cytometry.The mice were fed with a high-fat diet to induce an atherosclerosis model,and treated with OA by gastric gavage.The mice were divided into the control group,the model group,and the OA administration group.The blood lipid and plaque formation in mice were detected.In addition,oxidative stress and mitochondrial structure and function changes in cells and mice were evaluated by transmission electron microscopy,JC-1 fluorescent probe,and Western blotting assays.The expression levels of proteins in the AMPK/Drp1 pathway were examined through Western blot.Results:OA markedly increased cell viability and migration rate of HUVECs,and decreased the adhesion rate of THP-1 cells and the apoptosis rate.OA significantly reduced serum lipid levels,such as total cholesterol and triglyceride,in mice and inhibited plaque formation in the aorta.OA also significantly increased the content of superoxide dismutase and catalase,alleviated mitochondrial damage,such as mitochondrial swelling and mitochondrial cristae reduction,reduced the number of mitochondria,increased adenosine triphosphate content,and significantly reduced p-Drp1(Ser616)/Drp1,MFF and FIS1 levels,increased p-AMPK/AMPK levels,activated AMPK,and then regulated DRP1 activity.Conclusions:OA activates AMPK,which in turn regulates the activity of DRP1 to restore normal mitochondrial dynamics and reduce atherosclerosis.
基金Deutsche Forschungsgemeinschaft(DFG,German Research Foundation),project numbers 324633948 and 409784463(DFG grants Hi 678/9-3 and Hi 678/10-2,FOR2953)to HHBundesministerium für Bildung und Forschung-BMBF,project number 16LW0463K to HT.
文摘Microglia are the resident macrophages of the central nervous system.They act as the first line of defense against pathogens and play essential roles in neuroinflammation and tissue repair after brain insult or in neurodegenerative and demyelinating diseases(Borst et al.,2021).Together with infiltrating monocyte-derived macrophages,microglia also play a critical role for brain tumor development,since immunosuppressive interactions between tumor cells and tumor-associated microglia and macrophages(TAM)are linked to malignant progression.This mechanism is of particular relevance in glioblastoma(GB),the deadliest form of brain cancer with a median overall survival of less than 15 months(Khan et al.,2023).Therefore,targeting microglia and macrophage activation is a promising strategy for therapeutic interference in brain disease.
基金supported by the Center for Cognition and Sociality,Institute for Basic Science(IBS)(IBS-R001-D2)(to WK).
文摘The early developmental period is a critical window during which brain cells mature and contribute to both brain development and later life functions.Gamma-aminobutyric acid(GABA),recognized as a major neurotransmitter,plays a crucial role in coordinating synapse formation,neuronal proliferation,and migration during this time.