In-situ reactive compatibilization of high-density polyethylene （HDPE）/ground tire rubber （GTR） blends by dicumyl peroxide （DCP） and HY-2045 - a kind of thermoplastic phenolic resin without catalyst was inves...In-situ reactive compatibilization of high-density polyethylene （HDPE）/ground tire rubber （GTR） blends by dicumyl peroxide （DCP） and HY-2045 - a kind of thermoplastic phenolic resin without catalyst was investigated by studying the mor-phology, stress and strain behavior, dynamic mechanical properties and crystallization performance of the blends. Scanning e-lectron microscopy （SEM） results show that there are a lot of fibrous materials distributing in the interface, which connects the dispersed phase with the matrix and obtains better interfacial strength for prominent mechanical properties. The addition of compatibilizers results in the decrease of crystallinity of the blends and the disappearance of an obvious yield phenomenon, which was proved by the differential scanning calorimeter （DSC） test and X-ray diffraction （XRD） characterization Although the crystallinity of the blends decreases,the tensile strength and tensile strain of the blends significantly increases, especially for the HDPE/GTR/DCP/HY-2045 blends, which is possibly attributed to the good compatibility of the blends owing to the in-situ interface crosslinking. In addition, it is found that the compatibilizing HDPE/GTR blends shows a higher tan^ peak temperature and a broaden transition peak for GTR phase.展开更多
The influences of hyperbranched polyethylenimine （hPEI）, which possesses many reactive amino end-groups, on the blending properties of bisphenol-A polycarbonate （PC） and amorphous polyamide （aPA） were systematic...The influences of hyperbranched polyethylenimine （hPEI）, which possesses many reactive amino end-groups, on the blending properties of bisphenol-A polycarbonate （PC） and amorphous polyamide （aPA） were systematically investigated. Scanning electron microscopy （SEM） and differential scanning calorimetry （DSC） were used to observe the effect of hPE1 on morphologies of PC and aPA phases in bulk blends. While the interfacial fracture toughness between planar PC and aPA layers with and without hPEI was studied by using augmented double cantilever beam （ADCB） method. Results show that the compatibility in PC/aPA blends can be significantly improved by adding a small amount of hPEI, mainly due to the interchange reactions between the polymers leading to the formation of block copolymers, cross-linked polymers and molecules with other constitutions. The augmented double cantilever beam experiments showed that the reactive process drastically reinforced the interfacial adhesion between planar layers of PC and aPA. However, degradation takes place during annealing at 180℃, which was responsible for the production of small molar mass species of PC.展开更多
Methyl vinyl silicone rubber (MVQ)/polypropylene (PP) thermoplastic vulcanizate (TPV) combines the good melt processability, recyclability and sealing performance as well as biosafety, stain and fluid resistance, and ...Methyl vinyl silicone rubber (MVQ)/polypropylene (PP) thermoplastic vulcanizate (TPV) combines the good melt processability, recyclability and sealing performance as well as biosafety, stain and fluid resistance, and thus it is especially suitable in bio-safety areas and wearable electronic devices, etc. Nevertheless, the compatibility between MVQ and PP phases is poor. A big challenge on the compatibilization of MVQ/PP blends is that neither MVQ nor PP contains any reactive groups. In this study, a dual reactive compatibilizer composed of ethylenemethyl acrylate-glycidyl methacrylate terpolymer (EMA-co-GMA) and maleic anhydride grafted polypropylene (PP-g-MAH) was designed for the compatibilization of MVQ/PP blends. During melt blending, a copolymer compatibilizer at the MVQ/PP interface can be formed because of the in situ reaction between EMA-co-GMA and PP-g-MAH. The thermodynamic predict of its compatibilization effect through calculating the spreading coefficient of the in situ formed copolymer indicates that it can well compatibilize MVQ/PP blends. The experimental results show that under the GMA/MAH molar ratio of 0.5/1, the interface thickness largely increase from 102 nm for non-compatibilized blend to 406 nm, and the average size of MVQ dispersed phase largely decreases from 2.3 µm to 0.36 µm, the Tg of the two phases shifts toward each other, the mixing torque and mechanical properties of the blend are increased, all indicating its good compatibilization effect. This study provides a good compatibilizing method for immiscible MVQ/PP blends with no reactive groups in both components for the preparation of high performance MVQ/PP TPVs.展开更多
Poor interfacial adhesion between biobased thermoplastics and natural fibers is recognized as a major drawback for biocomposites.To be applicable for the large-scale production,a simple method to handle is of importan...Poor interfacial adhesion between biobased thermoplastics and natural fibers is recognized as a major drawback for biocomposites.To be applicable for the large-scale production,a simple method to handle is of importance.This work presented poly(lactic acid)(PLA)reinforced with short-fiber and three reactive agents including anhydride and epoxide groups were selected as compatibilizers.Biocomposites were prepared by one-step meltmixing methods.The influence of reactive agents on mechanical,dynamic mechanical properties and morphology of PLA biocomposites were investigated.Tensile strength and storage modulus of PLA biocomposites incorporated with epoxide-based reactive agent was increased 13.9%and 37.4%compared to non-compatibilized PLA biocomposite,which was higher than adding anhydride-based reactive agent.SEM micrographs and Molau test exhibited an improvement of interfacial fiber-matrix adhesion in the PLA biocomposites incorporated with epoxide-based reactive agent.FTIR revealed the chemical reaction between the fiber and PLA with the presence of epoxide-based reactive agents.展开更多
Astrocytes are the most abundant type of glial cell in the central nervous system.Upon injury and inflammation,astrocytes become reactive and undergo morphological and functional changes.Depending on their phenotypic ...Astrocytes are the most abundant type of glial cell in the central nervous system.Upon injury and inflammation,astrocytes become reactive and undergo morphological and functional changes.Depending on their phenotypic classification as A1 or A2,reactive astrocytes contribute to both neurotoxic and neuroprotective responses,respectively.However,this binary classification does not fully capture the diversity of astrocyte responses observed across different diseases and injuries.Transcriptomic analysis has revealed that reactive astrocytes have a complex landscape of gene expression profiles,which emphasizes the heterogeneous nature of their reactivity.Astrocytes actively participate in regulating central nervous system inflammation by interacting with microglia and other cell types,releasing cytokines,and influencing the immune response.The phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT)signaling pathway is a central player in astrocyte reactivity and impacts various aspects of astrocyte behavior,as evidenced by in silico,in vitro,and in vivo results.In astrocytes,inflammatory cues trigger a cascade of molecular events,where nuclear factor-κB serves as a central mediator of the pro-inflammatory responses.Here,we review the heterogeneity of reactive astrocytes and the molecular mechanisms underlying their activation.We highlight the involvement of various signaling pathways that regulate astrocyte reactivity,including the PI3K/AKT/mammalian target of rapamycin(mTOR),αvβ3 integrin/PI3K/AKT/connexin 43,and Notch/PI3K/AKT pathways.While targeting the inactivation of the PI3K/AKT cellular signaling pathway to control reactive astrocytes and prevent central nervous system damage,evidence suggests that activating this pathway could also yield beneficial outcomes.This dual function of the PI3K/AKT pathway underscores its complexity in astrocyte reactivity and brain function modulation.The review emphasizes the importance of employing astrocyte-exclusive models to understand their functions accurately and these models are essential for clarifying astrocyte behavior.The findings should then be validated using in vivo models to ensure real-life relevance.The review also highlights the significance of PI3K/AKT pathway modulation in preventing central nervous system damage,although further studies are required to fully comprehend its role due to varying factors such as different cell types,astrocyte responses to inflammation,and disease contexts.Specific strategies are clearly necessary to address these variables effectively.展开更多
The penetration-deflagration coupling damage performance of rod-like reactive shaped charge pene-trator(RRSCP)impacting thick steel plates is investigated by theoretical analysis and experiments.A penetration-deflagra...The penetration-deflagration coupling damage performance of rod-like reactive shaped charge pene-trator(RRSCP)impacting thick steel plates is investigated by theoretical analysis and experiments.A penetration-deflagration coupling damage model is developed to predict the penetration depth and cratering diameter.Four type of aluminum-polytetrafluoroethylene-copper(Al-PTFE-Cu)reactive liners with densities of 2.3,2.7,3.5,and 4.5 g·cm^(-3) are selected to conduct the penetration experiments.The comparison results show that model predictions are in good agreement with the experimental data.By comparing the penetration depth and cratering diameter in the inert penetration mode and the penetration-deflagration coupling mode,the influence mechanism that the penetration-induced chemical response is unfavorable to penetration but has an enhanced cratering effect is revealed.From the formation characteristics,penetration effect and penetration-induced chemical reaction be-haviors,the influence of reactive liner density on the penetration-deflagration performance is further analyzed.The results show that increasing the density of reactive liner significantly increases both the kinetic energy and length of the reactive penetrator,meanwhile effectively reduces the weakened effect of penetration-induced chemical response,resulting in an enhanced penetration capability.However,due to the decreased diameter and potential energy content of reactive penetrator,the cratering capa-bility is weakened significantly.展开更多
Honglian type-cytoplasmic male sterility(HL-CMS)is caused by the inter-communication between the nucleus and mitochondria.However,the mechanisms by which sterility genes regulate metabolic alterations and changes in m...Honglian type-cytoplasmic male sterility(HL-CMS)is caused by the inter-communication between the nucleus and mitochondria.However,the mechanisms by which sterility genes regulate metabolic alterations and changes in mitochondrial morphology in the pollen of HL-CMS remain unclear.In this study,we compared the morphological differences between the pollen of the male sterile line YA and the near-isogenic line NIL-Rf6 using hematoxylin-eosin staining and 4ʹ,6-diamidino-2-phenylindole(DAPI)staining.HL-CMS is characterized by gametophytic sterility,where the aborted pollen grains are empty,and the tapetal layer remains intact.Transmission electron microscopy was employed to observe mitochondrial morphological changes at the microspore stage,revealing significant mitochondrial alterations,characterized by the formation of'large spherical mitochondria',occurred at the binucleate stage in the YA line.Additionally,metabolomics analysis revealed decreased levels of metabolites associated with the carbohydrate and flavonoid pathways.Notably,the decrease in flavonoids was found to contribute to an elevation in reactive oxygen species(ROS)levels.Therefore,we propose a model in which rice fertility is modulated by the levels of pollen carbohydrates and flavonoid metabolites,with impaired mitochondrial energy production and reduced flavonoid biosynthesis as the main causes of ROS accumulation and pollen abortion in rice.展开更多
The presence of heavy metals in soil negatively impacts its mechanical properties.Reactive MgO carbonation presents a promising approach to enhance the solidification of Pb-contaminated sandy soils.However,the mechani...The presence of heavy metals in soil negatively impacts its mechanical properties.Reactive MgO carbonation presents a promising approach to enhance the solidification of Pb-contaminated sandy soils.However,the mechanical properties and structural behavior of contaminated soils during carbonation can vary significantly due to differences in soil composition.This study examines the potential application and underlying mechanisms of reactive MgO carbonation in improving the mechanical properties of Pb-contaminated red clay.The findings demonstrate that Pb-contaminated red clay transitions from a plastic to a brittle state following reactive MgO carbonation.After 1 h of treatment,the strength of the red clay exceeded 3 MPa,even at high Pb^(2+)concentrations.The deformation modulus to unconfined compressive strength(UCS)ratio was calculated to be 37.761,with the failure strain primarily ranging from 1.5%to 4.0%.A strength prediction model for the reactive MgO-stabilized Pb-contaminated red clay was proposed,which showed good predictive accuracy.Furthermore,reactive MgO carbonation significantly reduced the Pb leaching concentration in the high-level Pb-contaminated soil to below 0.1 mg/L.Microscopic analysis revealed that an optimal amount of hydrated magnesium carbonates(HMCs)formed a stable and compact structure with the soil particles.However,long-term carbonation causes red clay particles to become sandy,and excessive HMCs can harm the soil structure.Therefore,to maximize the strength improvement while avoiding structural damage,the carbonation time should be controlled to 1 h.展开更多
Considering the uncertainty of grid connection of electric vehicle charging stations and the uncertainty of new energy and residential electricity load,a spatio-temporal decoupling strategy of dynamic reactive power o...Considering the uncertainty of grid connection of electric vehicle charging stations and the uncertainty of new energy and residential electricity load,a spatio-temporal decoupling strategy of dynamic reactive power optimization based on clustering-local relaxation-correction is proposed.Firstly,the k-medoids clustering algorithm is used to divide the reduced power scene into periods.Then,the discrete variables and continuous variables are optimized in the same period of time.Finally,the number of input groups of parallel capacitor banks(CB)in multiple periods is fixed,and then the secondary static reactive power optimization correction is carried out by using the continuous reactive power output device based on the static reactive power compensation device(SVC),the new energy grid-connected inverter,and the electric vehicle charging station.According to the characteristics of the model,a hybrid optimization algorithm with a cross-feedback mechanism is used to solve different types of variables,and an improved artificial hummingbird algorithm based on tent chaotic mapping and adaptive mutation is proposed to improve the solution efficiency.The simulation results show that the proposed decoupling strategy can obtain satisfactory optimization resultswhile strictly guaranteeing the dynamic constraints of discrete variables,and the hybrid algorithm can effectively solve the mixed integer nonlinear optimization problem.展开更多
Alzheimer'sdisease(AD)isaprogressive neurodegenerative disorder characterized by cognitive impairment and distinct neuropathological features,including amyloid-βplaques,neurofibrillary tangles,and reactive astrog...Alzheimer'sdisease(AD)isaprogressive neurodegenerative disorder characterized by cognitive impairment and distinct neuropathological features,including amyloid-βplaques,neurofibrillary tangles,and reactive astrogliosis.Developing effective diagnostic,preventative,and therapeutic strategies for AD necessitates the establishment of animal models that accurately recapitulate the pathophysiological processes of the disease.Existing transgenic mouse models have significantly contributed to understanding AD pathology but often fail to replicate the complexity of human AD.Additionally,these models are limited in their ability to elucidate the interplay among amyloid-βplaques,neurofibrillary tangles,and reactive astrogliosis due to the absence of spatially and temporally specific genetic manipulation.In this study,we introduce a novel AD mouse model(APP/PS1-TauP301L-Adeno mice)designed to rapidly induce pathological symptoms and enhance understanding of AD mechanisms.Neurofibrillary tangles and severe reactive astrogliosis were induced by injecting AAVDJ-EF1a-hTauP301L-EGFP and Adeno-GFAP-GFP viruses into the hippocampi of 5-month-old APP/PS1 mice.Three months post-injection,these mice exhibited pronounced astrogliosis,substantial amyloid-βplaque accumulation,extensiveneurofibrillarytangles,accelerated neuronal loss,elevated astrocytic GABA levels,and significant spatial memory deficits.Notably,these pathological features were less severe in AAVTauP301L-expressing APP/PS1 mice without augmented reactive astrogliosis.These findings indicate an exacerbating role of severe reactive astrogliosis in amyloid-βplaque and neurofibrillary tangle-associated pathology.The APP/PS1-TauP301L-Adeno mouse model provides a valuable tool for advancing therapeutic research aimed at mitigating the progression of AD.展开更多
A high-density tungsten-zirconium-titanium(W-Zr-Ti)reactive alloy was prepared by powder metallurgy.This alloy exhibits high density,high strength,and violent energy release characteristics,resulting in outstanding pe...A high-density tungsten-zirconium-titanium(W-Zr-Ti)reactive alloy was prepared by powder metallurgy.This alloy exhibits high density,high strength,and violent energy release characteristics,resulting in outstanding penetration and ignition abilities.Dynamic impact experiment demonstrated its strain rate hardening effect,and the energetic characteristics were investigated by digital image processing technique and thermal analysis experiment.The results show that W-Zr-Ti reactive alloy performs compressive strength of 2.25 GPa at 5784 s^(-1)strain rate,and its exothermic reaction occurs at about 961 K.Based on the explosion test and shock wave theory,thresholds of enhanced damage effect are less than 35.77 GPa and 5.18×10^(4)kJ/m^(2)for shock pressure and energy,respectively.Furthermore,the transformation of fracture behavior and failure mechanism is revealed,which causes the increase in compressive strength and reaction intensity under dynamic loading.展开更多
Reactive oxygen species(ROS),including singlet oxygen(^(1)O_(2)),hydroxyl radicals(·OH),and superoxide anions(O_(2)^(·-)),are highly reactive molecules that play central roles in many chemical,biological,and...Reactive oxygen species(ROS),including singlet oxygen(^(1)O_(2)),hydroxyl radicals(·OH),and superoxide anions(O_(2)^(·-)),are highly reactive molecules that play central roles in many chemical,biological,and environmental processes due to their strong oxidative power[1].Generating ROS in a controlled manner under mild conditions is essential for achieving selective oxidation reactions.Light-driven methods are especially appealing for this purpose,as they offer precise control over where and when ROS are produced.展开更多
Aiming to solve the problem of large discharge and severe pollution of reactive dyeing wastewater for wool fabrics,peroxodisulfate(SPS)was used for the degradation and recycling of dyeing wastewater containing reactiv...Aiming to solve the problem of large discharge and severe pollution of reactive dyeing wastewater for wool fabrics,peroxodisulfate(SPS)was used for the degradation and recycling of dyeing wastewater containing reactive dye Lanasol Red CE.The process of degrading the reactive dye was determined by using the dye residual rate as the evaluation index.The feasibility of reactive dyeing of wool fabrics using recycled dyeing wastewater was confirmed by measuring the dye uptake,exhaustion and fixation rates,as well as color parameters and fastness of the dyed fabrics.The results showed that the appropriate conditions for degrading Lanasol Red CE were 0.2 g/L SPS,an initial pH value of 3 and 100℃for 30 min.Under these conditions,the dye degradation rate was as high as 93.14%.When the recycled dyeing wastewater was used for dyeing of wool fabrics,the exhaustion rate of Lanasol Red CE exceeded 99%,and the fixation rate was higher than that achieved by the conventional dyeing process.Under the same dyeing conditions,the recycled-dyed fabrics appeared darker.When the number of cycles was fewer than five,the effect on color fastness was not obvious.Although the color fastness to rubbing and washing of the fabrics dyed in the 10th cycle decreased by half a grade and 1 grade,respectively,compared to that of the fabrics dyed with the conventional dyeing process,they still met the production requirements.展开更多
Microwave discharge plasma in liquid(MDPL)is a new type of water purification technology with a high mass transfer efficiency.It is a kind of low-temperature plasma technology.The reactive species produced by the disc...Microwave discharge plasma in liquid(MDPL)is a new type of water purification technology with a high mass transfer efficiency.It is a kind of low-temperature plasma technology.The reactive species produced by the discharge can efficiently act on the pollutants.To clarify the application prospects of MDPL in water treatment,the discharge performance,practical application,and pollutant degradation mechanism of MDPL were studied in this work.The effects of power,conductivity,pH,and Fe^(2+)concentration on the amount of reactive species produced by the discharge were explored.The most common and refractory perfluorinated compounds(perfluorooctanoic acid(PFOA)and perfluorooctane sulfonate(PFOS)in water environments are degraded by MDPL technology.The highest defluorination of PFOA was 98.8% and the highest defluorination of PFOS was 92.7%.The energy consumption efficiency of 50% defluorination(G_(50-F))of PFOA degraded by MDPL is 78.43 mg/kWh,PFOS is 42.19 mg/kWh.The results show that the MDPL technology is more efficient and cleaner for the degradation of perfluorinated compounds.Finally,the reaction path and pollutant degradation mechanisms of MDPL production were analyzed.The results showed that MDPL technology can produce a variety of reactive species and has a good treatment effect for refractory perfluorinated pollutants.展开更多
Particulate matter(PM)can cause adverse health effects by overproducing reactive oxygen species(ROS).Although the ability of PM to induce ROS generation depends on its composi-tion and environmental factors.This study...Particulate matter(PM)can cause adverse health effects by overproducing reactive oxygen species(ROS).Although the ability of PM to induce ROS generation depends on its composi-tion and environmental factors.This study explores how photo-oxidation affects ROS gen-eration from aromatic compounds(ACs,including catechol(CAT),phthalic acid(PA),and 4,4-oxydibenzoic acid(4,4-OBA))and their mixtures with transition metals(TMs,includ-ing Fe(II),Mn(II),and Cu(II))using Fourier-transform infrared(FTIR)and Ultraviolet-visible spectroscopy(UV-Vis).Results showed that photo-oxidation facilitated ROS generation from ACs.CAT-Fe(II)/Cu(II)showed synergistic effects,but 4,4-OBA-Fe(II)/Cu(II)showed antag-onistic effects.ACs-Mn(II)and PA-Fe(II)/Cu(II)exhibited synergistic effects first and then showed antagonistic effects.The different interactions were due to complexation between ACs and TMs.The photo-oxidized ACs-TMs significantly enhanced ROS generation com-pared with ACs-TMs.The study suggested the photo-oxidation mechanism involved that the transfer ofπ-electrons from the ground to an excited state in benzene rings and func-tional groups,leading to the breakage and formation of chemical bonds or easierπ-electron transfer from ACs to TMs.The former could generate ROS directly or produce polymers that promoted ROS generation,while the latter promoted ROS generation by transferringπ-electrons to dissolved oxygen quickly.Our study revealed that both interactions among components and photo-oxidation significantly influenced ROS generation.Future studies should integrate broader atmospheric factors and PM components to fully assess oxidative potential and health impacts.展开更多
BACKGROUND Colon cancer is one of the most common malignancies worldwide,and chemo-therapy is a widely used strategy in colon cancer clinical therapy.Chemotherapy resistance is the main cause of recurrence and progres...BACKGROUND Colon cancer is one of the most common malignancies worldwide,and chemo-therapy is a widely used strategy in colon cancer clinical therapy.Chemotherapy resistance is the main cause of recurrence and progression in colon cancer.Thus,novel drugs for treatment are urgently needed.Tetramethylpyrazine(TMP),a component of the traditional Chinese medicine Chuanxiong Hort,has been proven to exhibit a beneficial effect in tumors.AIM To investigate the potential anticancer activity of TMP in colon cancer and the underlying mechanisms.METHODS Colon cancer cells were incubated with different concentrations of TMP.Cell viability was evaluated by crystal violet staining assay,and cell apoptosis was assessed by flow cytometry.Apoptosis-associated protein expression was measured using Western blot analysis.Intracellular reactive oxygen species(ROS)levels were assessed by flow cytometry using DCF fluorescence intensity.Xeno-grafts were established by the subcutaneous injection of colon cancer cells into nude mice;tumor growth was monitored and intracellular ROS was detected in tumors by malondialdehyde assay.RESULTS TMP induced apoptosis of colon cancer cells via the activation of the mitochon-drial pathway.TMP increased the generation of intracellular ROS and triggered mitochondria-mediated apoptosis in a caspase-dependent manner.CONCLUSION Our study demonstrates that TMP induces the apoptosis of colon cancer cells and increases the generation of intracellular ROS.TMP triggers mitochondria-mediated apoptosis in a caspase-dependent manner.The accumu-lation of intracellular ROS is involved in TMP-induced apoptosis.Our findings suggest that TMP may be a potential therapeutic drug for the treatment of colon cancer.展开更多
Background:Theworld is nowexperiencing many crises and adversities of great impact that pose serious threats to both physical and mental health.Threats to mental health include major depressive disorder,which can be s...Background:Theworld is nowexperiencing many crises and adversities of great impact that pose serious threats to both physical and mental health.Threats to mental health include major depressive disorder,which can be severe and disabling.The current study aimed to identify the prevalence of one type of depressive disorder,reactive depression(RD),and its relationship to demographic and psychological variables.Methods:For this study,RD is defined as an abnormal emotional response to traumatic situations involving mood difficulties.This study created an online self-report reactive depression questionnaire consisting of 23 items distributed across three subscales:1)bad feelings and life attitudes,2)loss of hope and loneliness,and 3)feeling sad and loss of confidence.The questionnaire was administered to a volunteer sample of 362male and female Iraqi university students.Exploratory Factor Analysis(EFA),Confirmatory Factor Analysis(CFA),t-tests,and one-way Analysis of Variance(ANOVA)were used to investigate exploratory and confirmatory factor structures of the questionnaire.Results:Evidence of reactive depression was found in 18.2%of the students.Female students had significantly higher levels of reactive depression than males(female N=205,mean=85.00,SD=11.30;male N=157,mean=76.46,SD=11.51).The high levels of reactive depression identified in these students demonstrate the value of assessing reactive depression in university students.Conclusion:The study underscores that the loss of emotional and psychological security,particularly in the face of traumatic and permanent events such as the death of a loved one,may contribute to the onset and progression of depressive symptoms.Future research should explore the role of specific cultural factors and further validate the reactive depression questionnaire in broader populations.Additionally,there is a need for improvedmental health support in Iraqi universities,particularly for female students,who may face unique challenges.展开更多
Herein, the electrochemical behaviors of Sr on inert W electrode and reactive Zn/Al electrodes were systematically investig-ated in LiCl–KCl–SrCl2molten salts at 773 K using various electrochemical methods. The chem...Herein, the electrochemical behaviors of Sr on inert W electrode and reactive Zn/Al electrodes were systematically investig-ated in LiCl–KCl–SrCl2molten salts at 773 K using various electrochemical methods. The chemical reaction potentials of Li and Sr on re-active Zn/Al electrodes were determined. We observed that Sr could be extracted by decreasing the activity of the deposited metal Sr onthe reactive electrode, although the standard reduction potential of Sr(II)/Sr was more negative than that of Li(I)/Li. The electrochemicalextraction products of Sr on reactive Zn and Al electrodes were Zn13Sr and Al4Sr, respectively, with no codeposition of Li observed.Based on the density functional theory calculations, both Zn13Sr and Al4Sr were identified as stable intermetallic compounds with Zn-/Al-rich phases. In LiCl–KCl molten salt containing 3wt% SrCl2, the coulombic efficiency of Sr in the Zn electrode was ~54%. The depolar-ization values for Sr on Zn and Al electrodes were 0.864 and 0.485 V, respectively, exhibiting a stronger chemical interaction between Znand Sr than between Al and Sr. This study suggests that using reactive electrodes can facilitate extraction of Sr accumulated while elec-trorefining molten salts, thereby enabling the purification and reuse of the salt and decreasing the volume of the nuclear waste.展开更多
Although sonodynamic therapy(SDT)is a promising cancer treatment that induces DNA and macromolecular damage through the generation of reactive oxygen species(ROS),its therapeutic efficacy is limited by local hypoxia a...Although sonodynamic therapy(SDT)is a promising cancer treatment that induces DNA and macromolecular damage through the generation of reactive oxygen species(ROS),its therapeutic efficacy is limited by local hypoxia and ROS defense mechanisms in tumors.This study propose d a novel tumor treatment approach,focusing on ROS-mediated therapy by targ eting the nucleus and depleting glutathione(GSH)levels,which was achieved through a nanoplatform(Pt^(2+)-CDs@PpIX)with integrated functions including GSH detection and depletion,pH-responsive drug release,and nuclear targeting.The Pt^(2+)-CDs@PpIX nanoplatform effectively differentiated normal and cancer cells and also exhibited excellent biocompatibility.Depletion of GSH levels and increased ROS sensitivity of cells significantly improved the effectiveness of SDT,as demonstrated in vitro using Pt^(2+)-CDs@PpIX,which also exhibited significant cellular uptake.Pt^(2+)-CDs@PpIX exerted potent antitumor effects in both two-dimensional and three-dimensional tum or microenvironment models(3 DM-7721).Moreover,in 3 DM-7721 models,hepatoma cells(SMMC-7721)demonstrated significant inhibition of motility,invasion,and colony formation after exposure to Pt^(2+)-CDs@PpIX.Furthermore,intravenous administration of the Pt^(2+)-CDs@PpIX nanoplatform enabled precise and rapid tumor-targeting,followed by ultrasound-triggered therapy,without adverse effects in nude mice.Hence,this nanoplatform provides a promising strategy for designing cancer therapies and delivering nuclear-targeted drugs.展开更多
Reactive oxygen species(ROS)are closely related to cell death,proliferation and inflammation.However,excessive ROS levels may exceed the cellular oxidative capacity and cause irreversible damage.Organisms are often in...Reactive oxygen species(ROS)are closely related to cell death,proliferation and inflammation.However,excessive ROS levels may exceed the cellular oxidative capacity and cause irreversible damage.Organisms are often inadvertently exposed to nanomaterials(NMs).Therefore,elucidating the specific routes of ROS generation induced by NMs is crucial for comprehending the toxicity mechanisms of NMs and regulating their potential applications.This paper provides a comprehensive review of the toxicity mechanisms and applications of NMs from three perspectives:(1)Organelle perspective.Investigating the impact of NMmediated ROS onmitochondria,unravelingmechanisms at the organelle level.(2)NMs’perspective.Exploring the broad applications and biosafety considerations of Nanozymes,a unique class of NMs.(3)Cellular system.Examining the toxic effects and mechanisms of NMs in cells at a holistic cellular level.Expanding on these perspectives,the paper scrutinizes the regulation of Fenton reactions by NMs in organisms.Furthermore,it introduces diseases resulting fromNM-mediated ROS at the organism level.This comprehensive review aims to provide valuable insights for studying NM-mediated mechanisms at both cellular and organism levels,offering considerations for the safe design of nanomaterials.展开更多
文摘In-situ reactive compatibilization of high-density polyethylene （HDPE）/ground tire rubber （GTR） blends by dicumyl peroxide （DCP） and HY-2045 - a kind of thermoplastic phenolic resin without catalyst was investigated by studying the mor-phology, stress and strain behavior, dynamic mechanical properties and crystallization performance of the blends. Scanning e-lectron microscopy （SEM） results show that there are a lot of fibrous materials distributing in the interface, which connects the dispersed phase with the matrix and obtains better interfacial strength for prominent mechanical properties. The addition of compatibilizers results in the decrease of crystallinity of the blends and the disappearance of an obvious yield phenomenon, which was proved by the differential scanning calorimeter （DSC） test and X-ray diffraction （XRD） characterization Although the crystallinity of the blends decreases,the tensile strength and tensile strain of the blends significantly increases, especially for the HDPE/GTR/DCP/HY-2045 blends, which is possibly attributed to the good compatibility of the blends owing to the in-situ interface crosslinking. In addition, it is found that the compatibilizing HDPE/GTR blends shows a higher tan^ peak temperature and a broaden transition peak for GTR phase.
基金financially supported by the National Natural Science Foundation of China(No.21004069)
文摘The influences of hyperbranched polyethylenimine （hPEI）, which possesses many reactive amino end-groups, on the blending properties of bisphenol-A polycarbonate （PC） and amorphous polyamide （aPA） were systematically investigated. Scanning electron microscopy （SEM） and differential scanning calorimetry （DSC） were used to observe the effect of hPE1 on morphologies of PC and aPA phases in bulk blends. While the interfacial fracture toughness between planar PC and aPA layers with and without hPEI was studied by using augmented double cantilever beam （ADCB） method. Results show that the compatibility in PC/aPA blends can be significantly improved by adding a small amount of hPEI, mainly due to the interchange reactions between the polymers leading to the formation of block copolymers, cross-linked polymers and molecules with other constitutions. The augmented double cantilever beam experiments showed that the reactive process drastically reinforced the interfacial adhesion between planar layers of PC and aPA. However, degradation takes place during annealing at 180℃, which was responsible for the production of small molar mass species of PC.
基金supported by the National Natural Science Foundation of China(No.51525301).
文摘Methyl vinyl silicone rubber (MVQ)/polypropylene (PP) thermoplastic vulcanizate (TPV) combines the good melt processability, recyclability and sealing performance as well as biosafety, stain and fluid resistance, and thus it is especially suitable in bio-safety areas and wearable electronic devices, etc. Nevertheless, the compatibility between MVQ and PP phases is poor. A big challenge on the compatibilization of MVQ/PP blends is that neither MVQ nor PP contains any reactive groups. In this study, a dual reactive compatibilizer composed of ethylenemethyl acrylate-glycidyl methacrylate terpolymer (EMA-co-GMA) and maleic anhydride grafted polypropylene (PP-g-MAH) was designed for the compatibilization of MVQ/PP blends. During melt blending, a copolymer compatibilizer at the MVQ/PP interface can be formed because of the in situ reaction between EMA-co-GMA and PP-g-MAH. The thermodynamic predict of its compatibilization effect through calculating the spreading coefficient of the in situ formed copolymer indicates that it can well compatibilize MVQ/PP blends. The experimental results show that under the GMA/MAH molar ratio of 0.5/1, the interface thickness largely increase from 102 nm for non-compatibilized blend to 406 nm, and the average size of MVQ dispersed phase largely decreases from 2.3 µm to 0.36 µm, the Tg of the two phases shifts toward each other, the mixing torque and mechanical properties of the blend are increased, all indicating its good compatibilization effect. This study provides a good compatibilizing method for immiscible MVQ/PP blends with no reactive groups in both components for the preparation of high performance MVQ/PP TPVs.
文摘Poor interfacial adhesion between biobased thermoplastics and natural fibers is recognized as a major drawback for biocomposites.To be applicable for the large-scale production,a simple method to handle is of importance.This work presented poly(lactic acid)(PLA)reinforced with short-fiber and three reactive agents including anhydride and epoxide groups were selected as compatibilizers.Biocomposites were prepared by one-step meltmixing methods.The influence of reactive agents on mechanical,dynamic mechanical properties and morphology of PLA biocomposites were investigated.Tensile strength and storage modulus of PLA biocomposites incorporated with epoxide-based reactive agent was increased 13.9%and 37.4%compared to non-compatibilized PLA biocomposite,which was higher than adding anhydride-based reactive agent.SEM micrographs and Molau test exhibited an improvement of interfacial fiber-matrix adhesion in the PLA biocomposites incorporated with epoxide-based reactive agent.FTIR revealed the chemical reaction between the fiber and PLA with the presence of epoxide-based reactive agents.
基金supported by Fondo Nacional de Desarrollo Científico y Tecnológico(FONDECYT)#1200836,#1210644,and#1240888,and Agencia Nacional de Investigación y Desarrollo(ANID)-FONDAP#15130011(to LL)FONDECYT#3230227(to MFG).
文摘Astrocytes are the most abundant type of glial cell in the central nervous system.Upon injury and inflammation,astrocytes become reactive and undergo morphological and functional changes.Depending on their phenotypic classification as A1 or A2,reactive astrocytes contribute to both neurotoxic and neuroprotective responses,respectively.However,this binary classification does not fully capture the diversity of astrocyte responses observed across different diseases and injuries.Transcriptomic analysis has revealed that reactive astrocytes have a complex landscape of gene expression profiles,which emphasizes the heterogeneous nature of their reactivity.Astrocytes actively participate in regulating central nervous system inflammation by interacting with microglia and other cell types,releasing cytokines,and influencing the immune response.The phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT)signaling pathway is a central player in astrocyte reactivity and impacts various aspects of astrocyte behavior,as evidenced by in silico,in vitro,and in vivo results.In astrocytes,inflammatory cues trigger a cascade of molecular events,where nuclear factor-κB serves as a central mediator of the pro-inflammatory responses.Here,we review the heterogeneity of reactive astrocytes and the molecular mechanisms underlying their activation.We highlight the involvement of various signaling pathways that regulate astrocyte reactivity,including the PI3K/AKT/mammalian target of rapamycin(mTOR),αvβ3 integrin/PI3K/AKT/connexin 43,and Notch/PI3K/AKT pathways.While targeting the inactivation of the PI3K/AKT cellular signaling pathway to control reactive astrocytes and prevent central nervous system damage,evidence suggests that activating this pathway could also yield beneficial outcomes.This dual function of the PI3K/AKT pathway underscores its complexity in astrocyte reactivity and brain function modulation.The review emphasizes the importance of employing astrocyte-exclusive models to understand their functions accurately and these models are essential for clarifying astrocyte behavior.The findings should then be validated using in vivo models to ensure real-life relevance.The review also highlights the significance of PI3K/AKT pathway modulation in preventing central nervous system damage,although further studies are required to fully comprehend its role due to varying factors such as different cell types,astrocyte responses to inflammation,and disease contexts.Specific strategies are clearly necessary to address these variables effectively.
基金supported by the National Natural Science Foundation of China(Grant No.12172052)the Foundation of State Key Laboratory of Explosion Science and Safety Protection(Grant No.QKKT24-02).
文摘The penetration-deflagration coupling damage performance of rod-like reactive shaped charge pene-trator(RRSCP)impacting thick steel plates is investigated by theoretical analysis and experiments.A penetration-deflagration coupling damage model is developed to predict the penetration depth and cratering diameter.Four type of aluminum-polytetrafluoroethylene-copper(Al-PTFE-Cu)reactive liners with densities of 2.3,2.7,3.5,and 4.5 g·cm^(-3) are selected to conduct the penetration experiments.The comparison results show that model predictions are in good agreement with the experimental data.By comparing the penetration depth and cratering diameter in the inert penetration mode and the penetration-deflagration coupling mode,the influence mechanism that the penetration-induced chemical response is unfavorable to penetration but has an enhanced cratering effect is revealed.From the formation characteristics,penetration effect and penetration-induced chemical reaction be-haviors,the influence of reactive liner density on the penetration-deflagration performance is further analyzed.The results show that increasing the density of reactive liner significantly increases both the kinetic energy and length of the reactive penetrator,meanwhile effectively reduces the weakened effect of penetration-induced chemical response,resulting in an enhanced penetration capability.However,due to the decreased diameter and potential energy content of reactive penetrator,the cratering capa-bility is weakened significantly.
基金supported by the National Natural Science Foundation of China(Grant No.32472185)the Key Research and Development Program of Hubei Province,China(Grant No.2022BFE003)the Hubei Agriculture Science and Technology Innovation Center program,and the National Rice Industry Technology System,China(Grant No.CARS-01-07).
文摘Honglian type-cytoplasmic male sterility(HL-CMS)is caused by the inter-communication between the nucleus and mitochondria.However,the mechanisms by which sterility genes regulate metabolic alterations and changes in mitochondrial morphology in the pollen of HL-CMS remain unclear.In this study,we compared the morphological differences between the pollen of the male sterile line YA and the near-isogenic line NIL-Rf6 using hematoxylin-eosin staining and 4ʹ,6-diamidino-2-phenylindole(DAPI)staining.HL-CMS is characterized by gametophytic sterility,where the aborted pollen grains are empty,and the tapetal layer remains intact.Transmission electron microscopy was employed to observe mitochondrial morphological changes at the microspore stage,revealing significant mitochondrial alterations,characterized by the formation of'large spherical mitochondria',occurred at the binucleate stage in the YA line.Additionally,metabolomics analysis revealed decreased levels of metabolites associated with the carbohydrate and flavonoid pathways.Notably,the decrease in flavonoids was found to contribute to an elevation in reactive oxygen species(ROS)levels.Therefore,we propose a model in which rice fertility is modulated by the levels of pollen carbohydrates and flavonoid metabolites,with impaired mitochondrial energy production and reduced flavonoid biosynthesis as the main causes of ROS accumulation and pollen abortion in rice.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFC3707900)the National Natural Science Foundation of China(Grant Nos.42030710 and 42472337).
文摘The presence of heavy metals in soil negatively impacts its mechanical properties.Reactive MgO carbonation presents a promising approach to enhance the solidification of Pb-contaminated sandy soils.However,the mechanical properties and structural behavior of contaminated soils during carbonation can vary significantly due to differences in soil composition.This study examines the potential application and underlying mechanisms of reactive MgO carbonation in improving the mechanical properties of Pb-contaminated red clay.The findings demonstrate that Pb-contaminated red clay transitions from a plastic to a brittle state following reactive MgO carbonation.After 1 h of treatment,the strength of the red clay exceeded 3 MPa,even at high Pb^(2+)concentrations.The deformation modulus to unconfined compressive strength(UCS)ratio was calculated to be 37.761,with the failure strain primarily ranging from 1.5%to 4.0%.A strength prediction model for the reactive MgO-stabilized Pb-contaminated red clay was proposed,which showed good predictive accuracy.Furthermore,reactive MgO carbonation significantly reduced the Pb leaching concentration in the high-level Pb-contaminated soil to below 0.1 mg/L.Microscopic analysis revealed that an optimal amount of hydrated magnesium carbonates(HMCs)formed a stable and compact structure with the soil particles.However,long-term carbonation causes red clay particles to become sandy,and excessive HMCs can harm the soil structure.Therefore,to maximize the strength improvement while avoiding structural damage,the carbonation time should be controlled to 1 h.
基金funded by the“Research and Application Project of Collaborative Optimization Control Technology for Distribution Station Area for High Proportion Distributed PV Consumption(4000-202318079A-1-1-ZN)”of the Headquarters of the State Grid Corporation.
文摘Considering the uncertainty of grid connection of electric vehicle charging stations and the uncertainty of new energy and residential electricity load,a spatio-temporal decoupling strategy of dynamic reactive power optimization based on clustering-local relaxation-correction is proposed.Firstly,the k-medoids clustering algorithm is used to divide the reduced power scene into periods.Then,the discrete variables and continuous variables are optimized in the same period of time.Finally,the number of input groups of parallel capacitor banks(CB)in multiple periods is fixed,and then the secondary static reactive power optimization correction is carried out by using the continuous reactive power output device based on the static reactive power compensation device(SVC),the new energy grid-connected inverter,and the electric vehicle charging station.According to the characteristics of the model,a hybrid optimization algorithm with a cross-feedback mechanism is used to solve different types of variables,and an improved artificial hummingbird algorithm based on tent chaotic mapping and adaptive mutation is proposed to improve the solution efficiency.The simulation results show that the proposed decoupling strategy can obtain satisfactory optimization resultswhile strictly guaranteeing the dynamic constraints of discrete variables,and the hybrid algorithm can effectively solve the mixed integer nonlinear optimization problem.
基金supported by the National Research Foundation of Korea (NRF)funded by the Ministry of Science,ICT&Future Planning (2022R1A2C2006229,2022R1A6A3A01086868)Korea Dementia Research Project through the Korea Dementia Research Center (KDRC)funded by the Ministry of Health&Welfare and Ministry of Science and ICT,Republic of Korea (RS-2024-00345328)KIST Institutional Grant (2E32851)。
文摘Alzheimer'sdisease(AD)isaprogressive neurodegenerative disorder characterized by cognitive impairment and distinct neuropathological features,including amyloid-βplaques,neurofibrillary tangles,and reactive astrogliosis.Developing effective diagnostic,preventative,and therapeutic strategies for AD necessitates the establishment of animal models that accurately recapitulate the pathophysiological processes of the disease.Existing transgenic mouse models have significantly contributed to understanding AD pathology but often fail to replicate the complexity of human AD.Additionally,these models are limited in their ability to elucidate the interplay among amyloid-βplaques,neurofibrillary tangles,and reactive astrogliosis due to the absence of spatially and temporally specific genetic manipulation.In this study,we introduce a novel AD mouse model(APP/PS1-TauP301L-Adeno mice)designed to rapidly induce pathological symptoms and enhance understanding of AD mechanisms.Neurofibrillary tangles and severe reactive astrogliosis were induced by injecting AAVDJ-EF1a-hTauP301L-EGFP and Adeno-GFAP-GFP viruses into the hippocampi of 5-month-old APP/PS1 mice.Three months post-injection,these mice exhibited pronounced astrogliosis,substantial amyloid-βplaque accumulation,extensiveneurofibrillarytangles,accelerated neuronal loss,elevated astrocytic GABA levels,and significant spatial memory deficits.Notably,these pathological features were less severe in AAVTauP301L-expressing APP/PS1 mice without augmented reactive astrogliosis.These findings indicate an exacerbating role of severe reactive astrogliosis in amyloid-βplaque and neurofibrillary tangle-associated pathology.The APP/PS1-TauP301L-Adeno mouse model provides a valuable tool for advancing therapeutic research aimed at mitigating the progression of AD.
基金National Natural Science Foundation of China(12002045)Supported by State Key Laboratory of Explosion Science and Safety Protection,Beijing Institute of Technology(QNKT22-09)。
文摘A high-density tungsten-zirconium-titanium(W-Zr-Ti)reactive alloy was prepared by powder metallurgy.This alloy exhibits high density,high strength,and violent energy release characteristics,resulting in outstanding penetration and ignition abilities.Dynamic impact experiment demonstrated its strain rate hardening effect,and the energetic characteristics were investigated by digital image processing technique and thermal analysis experiment.The results show that W-Zr-Ti reactive alloy performs compressive strength of 2.25 GPa at 5784 s^(-1)strain rate,and its exothermic reaction occurs at about 961 K.Based on the explosion test and shock wave theory,thresholds of enhanced damage effect are less than 35.77 GPa and 5.18×10^(4)kJ/m^(2)for shock pressure and energy,respectively.Furthermore,the transformation of fracture behavior and failure mechanism is revealed,which causes the increase in compressive strength and reaction intensity under dynamic loading.
文摘Reactive oxygen species(ROS),including singlet oxygen(^(1)O_(2)),hydroxyl radicals(·OH),and superoxide anions(O_(2)^(·-)),are highly reactive molecules that play central roles in many chemical,biological,and environmental processes due to their strong oxidative power[1].Generating ROS in a controlled manner under mild conditions is essential for achieving selective oxidation reactions.Light-driven methods are especially appealing for this purpose,as they offer precise control over where and when ROS are produced.
基金Youth Foundation of Hebei Province Department of Education Fund,China(No.QN2023090)Opening Project of Textile Ecological Dyeing and Finishing Key Laboratory of Sichuan Province(Chengdu Textile College),China(No.2024DF-AO2)Innovation and Entrepreneurship Training Program for College Students,China(No.202410082023)。
文摘Aiming to solve the problem of large discharge and severe pollution of reactive dyeing wastewater for wool fabrics,peroxodisulfate(SPS)was used for the degradation and recycling of dyeing wastewater containing reactive dye Lanasol Red CE.The process of degrading the reactive dye was determined by using the dye residual rate as the evaluation index.The feasibility of reactive dyeing of wool fabrics using recycled dyeing wastewater was confirmed by measuring the dye uptake,exhaustion and fixation rates,as well as color parameters and fastness of the dyed fabrics.The results showed that the appropriate conditions for degrading Lanasol Red CE were 0.2 g/L SPS,an initial pH value of 3 and 100℃for 30 min.Under these conditions,the dye degradation rate was as high as 93.14%.When the recycled dyeing wastewater was used for dyeing of wool fabrics,the exhaustion rate of Lanasol Red CE exceeded 99%,and the fixation rate was higher than that achieved by the conventional dyeing process.Under the same dyeing conditions,the recycled-dyed fabrics appeared darker.When the number of cycles was fewer than five,the effect on color fastness was not obvious.Although the color fastness to rubbing and washing of the fabrics dyed in the 10th cycle decreased by half a grade and 1 grade,respectively,compared to that of the fabrics dyed with the conventional dyeing process,they still met the production requirements.
基金supported by National Natural Science Foundation of China(Nos.12475258,12111530008 and 11675031)Major Scientific Research Project of Hebei Transportation Investment Group in 2024([202]155)the support of the Fundamental Research Funds for the Central Universities(No.3132023503)。
文摘Microwave discharge plasma in liquid(MDPL)is a new type of water purification technology with a high mass transfer efficiency.It is a kind of low-temperature plasma technology.The reactive species produced by the discharge can efficiently act on the pollutants.To clarify the application prospects of MDPL in water treatment,the discharge performance,practical application,and pollutant degradation mechanism of MDPL were studied in this work.The effects of power,conductivity,pH,and Fe^(2+)concentration on the amount of reactive species produced by the discharge were explored.The most common and refractory perfluorinated compounds(perfluorooctanoic acid(PFOA)and perfluorooctane sulfonate(PFOS)in water environments are degraded by MDPL technology.The highest defluorination of PFOA was 98.8% and the highest defluorination of PFOS was 92.7%.The energy consumption efficiency of 50% defluorination(G_(50-F))of PFOA degraded by MDPL is 78.43 mg/kWh,PFOS is 42.19 mg/kWh.The results show that the MDPL technology is more efficient and cleaner for the degradation of perfluorinated compounds.Finally,the reaction path and pollutant degradation mechanisms of MDPL production were analyzed.The results showed that MDPL technology can produce a variety of reactive species and has a good treatment effect for refractory perfluorinated pollutants.
基金supported by the Weiqiao-UCAS Special Projects on Low-Carbon Technology Development(No.GYY-DTFZ-2022-007)the Fundamental Research Funds for the Central Universities(No.E0E48927×2)the National Natural Science Foundation of China(No.21677145).
文摘Particulate matter(PM)can cause adverse health effects by overproducing reactive oxygen species(ROS).Although the ability of PM to induce ROS generation depends on its composi-tion and environmental factors.This study explores how photo-oxidation affects ROS gen-eration from aromatic compounds(ACs,including catechol(CAT),phthalic acid(PA),and 4,4-oxydibenzoic acid(4,4-OBA))and their mixtures with transition metals(TMs,includ-ing Fe(II),Mn(II),and Cu(II))using Fourier-transform infrared(FTIR)and Ultraviolet-visible spectroscopy(UV-Vis).Results showed that photo-oxidation facilitated ROS generation from ACs.CAT-Fe(II)/Cu(II)showed synergistic effects,but 4,4-OBA-Fe(II)/Cu(II)showed antag-onistic effects.ACs-Mn(II)and PA-Fe(II)/Cu(II)exhibited synergistic effects first and then showed antagonistic effects.The different interactions were due to complexation between ACs and TMs.The photo-oxidized ACs-TMs significantly enhanced ROS generation com-pared with ACs-TMs.The study suggested the photo-oxidation mechanism involved that the transfer ofπ-electrons from the ground to an excited state in benzene rings and func-tional groups,leading to the breakage and formation of chemical bonds or easierπ-electron transfer from ACs to TMs.The former could generate ROS directly or produce polymers that promoted ROS generation,while the latter promoted ROS generation by transferringπ-electrons to dissolved oxygen quickly.Our study revealed that both interactions among components and photo-oxidation significantly influenced ROS generation.Future studies should integrate broader atmospheric factors and PM components to fully assess oxidative potential and health impacts.
文摘BACKGROUND Colon cancer is one of the most common malignancies worldwide,and chemo-therapy is a widely used strategy in colon cancer clinical therapy.Chemotherapy resistance is the main cause of recurrence and progression in colon cancer.Thus,novel drugs for treatment are urgently needed.Tetramethylpyrazine(TMP),a component of the traditional Chinese medicine Chuanxiong Hort,has been proven to exhibit a beneficial effect in tumors.AIM To investigate the potential anticancer activity of TMP in colon cancer and the underlying mechanisms.METHODS Colon cancer cells were incubated with different concentrations of TMP.Cell viability was evaluated by crystal violet staining assay,and cell apoptosis was assessed by flow cytometry.Apoptosis-associated protein expression was measured using Western blot analysis.Intracellular reactive oxygen species(ROS)levels were assessed by flow cytometry using DCF fluorescence intensity.Xeno-grafts were established by the subcutaneous injection of colon cancer cells into nude mice;tumor growth was monitored and intracellular ROS was detected in tumors by malondialdehyde assay.RESULTS TMP induced apoptosis of colon cancer cells via the activation of the mitochon-drial pathway.TMP increased the generation of intracellular ROS and triggered mitochondria-mediated apoptosis in a caspase-dependent manner.CONCLUSION Our study demonstrates that TMP induces the apoptosis of colon cancer cells and increases the generation of intracellular ROS.TMP triggers mitochondria-mediated apoptosis in a caspase-dependent manner.The accumu-lation of intracellular ROS is involved in TMP-induced apoptosis.Our findings suggest that TMP may be a potential therapeutic drug for the treatment of colon cancer.
文摘Background:Theworld is nowexperiencing many crises and adversities of great impact that pose serious threats to both physical and mental health.Threats to mental health include major depressive disorder,which can be severe and disabling.The current study aimed to identify the prevalence of one type of depressive disorder,reactive depression(RD),and its relationship to demographic and psychological variables.Methods:For this study,RD is defined as an abnormal emotional response to traumatic situations involving mood difficulties.This study created an online self-report reactive depression questionnaire consisting of 23 items distributed across three subscales:1)bad feelings and life attitudes,2)loss of hope and loneliness,and 3)feeling sad and loss of confidence.The questionnaire was administered to a volunteer sample of 362male and female Iraqi university students.Exploratory Factor Analysis(EFA),Confirmatory Factor Analysis(CFA),t-tests,and one-way Analysis of Variance(ANOVA)were used to investigate exploratory and confirmatory factor structures of the questionnaire.Results:Evidence of reactive depression was found in 18.2%of the students.Female students had significantly higher levels of reactive depression than males(female N=205,mean=85.00,SD=11.30;male N=157,mean=76.46,SD=11.51).The high levels of reactive depression identified in these students demonstrate the value of assessing reactive depression in university students.Conclusion:The study underscores that the loss of emotional and psychological security,particularly in the face of traumatic and permanent events such as the death of a loved one,may contribute to the onset and progression of depressive symptoms.Future research should explore the role of specific cultural factors and further validate the reactive depression questionnaire in broader populations.Additionally,there is a need for improvedmental health support in Iraqi universities,particularly for female students,who may face unique challenges.
基金financially supported by the National Postdoctoral Program for Innovative Talents, China (No. BX2021327)the National Natural Science Foundation of China (Nos. 22206194 and U2267222)+1 种基金the Ningbo Natural Science Foundation of China (No. 2023J337)the Yongjiang Talent Introduction Programme, China (No. 2 021A-161-G)。
文摘Herein, the electrochemical behaviors of Sr on inert W electrode and reactive Zn/Al electrodes were systematically investig-ated in LiCl–KCl–SrCl2molten salts at 773 K using various electrochemical methods. The chemical reaction potentials of Li and Sr on re-active Zn/Al electrodes were determined. We observed that Sr could be extracted by decreasing the activity of the deposited metal Sr onthe reactive electrode, although the standard reduction potential of Sr(II)/Sr was more negative than that of Li(I)/Li. The electrochemicalextraction products of Sr on reactive Zn and Al electrodes were Zn13Sr and Al4Sr, respectively, with no codeposition of Li observed.Based on the density functional theory calculations, both Zn13Sr and Al4Sr were identified as stable intermetallic compounds with Zn-/Al-rich phases. In LiCl–KCl molten salt containing 3wt% SrCl2, the coulombic efficiency of Sr in the Zn electrode was ~54%. The depolar-ization values for Sr on Zn and Al electrodes were 0.864 and 0.485 V, respectively, exhibiting a stronger chemical interaction between Znand Sr than between Al and Sr. This study suggests that using reactive electrodes can facilitate extraction of Sr accumulated while elec-trorefining molten salts, thereby enabling the purification and reuse of the salt and decreasing the volume of the nuclear waste.
基金supported by the National Natural Science Foundation of China(No.62031022)the Sha nxi Provincial Basic Research Project(Nos.202103021221006 and 20210302123040)+2 种基金the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(No.2021L044)the Key R&D Program of Shanxi Province(No.202302130501006)the Shanxi‒Zheda Institute of Advanced Materials and Chemical Engineering(No.2022SX-TD026).
文摘Although sonodynamic therapy(SDT)is a promising cancer treatment that induces DNA and macromolecular damage through the generation of reactive oxygen species(ROS),its therapeutic efficacy is limited by local hypoxia and ROS defense mechanisms in tumors.This study propose d a novel tumor treatment approach,focusing on ROS-mediated therapy by targ eting the nucleus and depleting glutathione(GSH)levels,which was achieved through a nanoplatform(Pt^(2+)-CDs@PpIX)with integrated functions including GSH detection and depletion,pH-responsive drug release,and nuclear targeting.The Pt^(2+)-CDs@PpIX nanoplatform effectively differentiated normal and cancer cells and also exhibited excellent biocompatibility.Depletion of GSH levels and increased ROS sensitivity of cells significantly improved the effectiveness of SDT,as demonstrated in vitro using Pt^(2+)-CDs@PpIX,which also exhibited significant cellular uptake.Pt^(2+)-CDs@PpIX exerted potent antitumor effects in both two-dimensional and three-dimensional tum or microenvironment models(3 DM-7721).Moreover,in 3 DM-7721 models,hepatoma cells(SMMC-7721)demonstrated significant inhibition of motility,invasion,and colony formation after exposure to Pt^(2+)-CDs@PpIX.Furthermore,intravenous administration of the Pt^(2+)-CDs@PpIX nanoplatform enabled precise and rapid tumor-targeting,followed by ultrasound-triggered therapy,without adverse effects in nude mice.Hence,this nanoplatform provides a promising strategy for designing cancer therapies and delivering nuclear-targeted drugs.
基金supported by the National Natural Science Foundation of China(No.22176206).
文摘Reactive oxygen species(ROS)are closely related to cell death,proliferation and inflammation.However,excessive ROS levels may exceed the cellular oxidative capacity and cause irreversible damage.Organisms are often inadvertently exposed to nanomaterials(NMs).Therefore,elucidating the specific routes of ROS generation induced by NMs is crucial for comprehending the toxicity mechanisms of NMs and regulating their potential applications.This paper provides a comprehensive review of the toxicity mechanisms and applications of NMs from three perspectives:(1)Organelle perspective.Investigating the impact of NMmediated ROS onmitochondria,unravelingmechanisms at the organelle level.(2)NMs’perspective.Exploring the broad applications and biosafety considerations of Nanozymes,a unique class of NMs.(3)Cellular system.Examining the toxic effects and mechanisms of NMs in cells at a holistic cellular level.Expanding on these perspectives,the paper scrutinizes the regulation of Fenton reactions by NMs in organisms.Furthermore,it introduces diseases resulting fromNM-mediated ROS at the organism level.This comprehensive review aims to provide valuable insights for studying NM-mediated mechanisms at both cellular and organism levels,offering considerations for the safe design of nanomaterials.
