Urbanization and environmental degradation have led to significant declines in water quality and aquatic ecosystem health,highlighting the urgent need for effective restoration efforts.This study applies an integrated...Urbanization and environmental degradation have led to significant declines in water quality and aquatic ecosystem health,highlighting the urgent need for effective restoration efforts.This study applies an integrated analysis approach to estimate the economic value and benefits of improvements in water quality and aquatic ecosystem services resulting from the Ecological Stream Restoration Project.Using survey data analyzed through the choice experiment(CE)method,we assessed respondents’preferences for various ecosystem services,including water-friendly services,ecological functions,water-level control,and water-quality purification.Three empirical analysis models—the Conditional Logit Model(CLM),Nested Logit Model(NL),and Error Component Logit Model(ECL)—were applied,with the ECL model identified as the most suitable for this study.From the physical impact assessment,we derived compensating variations to estimate the annual economic benefits of the project.The estimated annual economic value of water quality improvement due to the Anyangcheon Ecological Stream Restoration Project ranged from approximately KRW 10.54 billion to KRW 21.44 billion,while the economic value of aquatic ecosystem improvement was estimated to range from KRW 6.05 billion to KRW 12.30 billion annually.This study provides analytic framework that can inform future ecological restoration projects and sustainable water management policies.展开更多
This study examines the empirical feasibility of quantitatively integrating environmental value information into Strategic Environmental Assessment(SEA).An analytical framework was established to incorporate environme...This study examines the empirical feasibility of quantitatively integrating environmental value information into Strategic Environmental Assessment(SEA).An analytical framework was established to incorporate environmental cost estimates into the SEA process by utilizing ecosystem service unit values provided by the Environmental Valuation Information System(EVIS),a national platform developed to support the evaluation of policies and projects.The framework was applied to a case study involving a multipurpose rural water development project in South Korea.Ecosystem service losses resulting from the project were quantified using biophysical indicators,such as vegetation biomass,forest area,and hydrological functions,and subsequently monetized through the application of the market price method,replacement cost method,and contingent valuation method.The total annual environmental cost was estimated to be approximately KRW 56.18 billion,with the majority attributable to losses in forest conservation and climate regulation services.These findings demonstrate that quantified environmental data can serve as a robust basis for alternative comparison and site evaluation within SEA.The study provides empirical evidence supporting the advancement of SEA from a predominantly procedural tool focused on environmental protection to a more comprehensive sustainability assessment framework that integrates environmental,economic,and social considerations.Furthermore,the results suggest that EVIS-based quantitative information holds potential for broader application in other national evaluation systems,such as preliminary feasibility studies and regulatory impact assessments.展开更多
The electrocatalytic oxidation of glycerol toward formic acid is one of the most promising pathways for transformation and utilization of glycerol.Herein,a series of well-defined Ni_(n)(SR)_(2n) nanoclusters(n=4,5,6;d...The electrocatalytic oxidation of glycerol toward formic acid is one of the most promising pathways for transformation and utilization of glycerol.Herein,a series of well-defined Ni_(n)(SR)_(2n) nanoclusters(n=4,5,6;denoted as Ni NCs)were prepared for the electrocatalytic glycerol oxidation toward formic acid,in which Ni_(6)-PET-50CV afforded the most excellent electrocatalytic performance with a high formic acid selectivity of 93% and a high glycerol conversion of 86%.This was attributed to the lowest charge transfer impedance and the most rapid reaction kinetics.Combined electrochemical measurements and X-ray absorption fine structure measurements revealed that the structures of Ni NCs remained intact after CV scanning pretreatment and electrocatalysis via forming the Ni–O bond.Additionally,the kinetic studies and in-situ Fourier transformed infrared suggested a sequential oxidation mechanism,in which the main reaction steps of glycerol→glyceraldehyde→glyceric acid were very rapid to produce a high selectivity of formic acid even though the low glycerol conversion.This work presents an opportunity to study Ni NCs for the efficient electrocatalytic oxidation of biomass-derived polyhydroxyl platform molecules to produce value-added carboxylic acids.展开更多
The emergence of cesium lead halide perovskite materials stable at air opened new prospects for the optoelectronic industry.In this work we present an approach to fabricating a flexible green perovskite light-emitting...The emergence of cesium lead halide perovskite materials stable at air opened new prospects for the optoelectronic industry.In this work we present an approach to fabricating a flexible green perovskite light-emitting electrochemical cell(PeLEC)with a CsPbBr_(3)perovskite active layer using a highly-ordered silicon nanowire(Si NW)array as a distributed electrode integrated within a thin polydimethylsiloxane film(PDMS).Numerical simulations reveal that Si NWs-based distributed electrode aids the improvement of carrier injection into the perovskite layer with an increased thickness and,therefore,the enhancement of light-emitting performance.The X-ray diffraction study shows that the perovskite layer synthesized on the PDMS membrane with Si NWs has a similar crystal structure to the ones synthesized on planar Si wafers.We perform a comparative analysis of the light-emitting devices’properties fabricated on rigid silicon substrates and flexible Si NW-based membranes released from substrates.Due to possible potential barriers in a flexible PeLEC between the bottom electrode(made of a network of single-walled carbon nanotube film)and Si NWs,the electroluminescence performance and Ⅰ-V properties of flexible devices deteriorated compared to rigid devices.The developed PeLECs pave the way for further development of inorganic flexible uniformly light-emitting devices with improved properties.展开更多
Olfactory receptors(ORs),the largest vertebrate multigene family,exhibit wide copy number variation among taxa,ranging from~100 to 4000.The ecological importance of smell has been suggested to positively correlate wit...Olfactory receptors(ORs),the largest vertebrate multigene family,exhibit wide copy number variation among taxa,ranging from~100 to 4000.The ecological importance of smell has been suggested to positively correlate with OR gene number,though debate exists on whether the number of total ORs,functional ORs,or the percentage of pseudogenes matters most.While olfaction has been poorly studied in most birds,Turkey Vultures(Cathartes aura)demonstrate keen olfactory ability,capable of foraging using smell alone.In contrast,Black Vultures(Coragyps atratus)have been thought to primarily use vision to locate food.Comparison of the OR genes in these two New World vultures presents an opportunity to examine the dynamics of OR evolution in related avian species that may differ in olfactory abilities.Using a PCR and cloning approach with degenerate primers,we sampled the OR subgenome in Turkey and Black Vultures,as well as Red-tailed Hawks(Buteo jamaicensis)and the distantly related Chicken(Gallus gallus),neither of which are thought to use olfaction extensively.Our results indicate that Turkey Vultures have many more OR genes than Red-tailed Hawks or chickens.Surprisingly,Black Vultures had an intermediate number of OR genes.The number of OR genes we estimated in the Turkey Vulture was much greater than previously reported in studies that used short-read sequencing.Additionally,we found that OR genes from New World vultures and Red-tailed Hawks form clades that were distinct from the clade that included most chicken OR genes,indicating that chickens share few OR orthologs with New World vultures or hawks.As previously observed in other animal groups,pseudogenes appeared throughout all clades and their percentage varied among taxa.These findings suggest the OR gene family is highly dynamic,changing rapidly over evolutionary time,and that taxa may have distinct suites of ORs in their genomes.展开更多
Objectives:The phytochemical investigation of traditional herbal medicines holds significant promise for modern drug discovery,particularly in cancer therapy.This study aimed to evaluate the cytotoxicity,apoptosis ind...Objectives:The phytochemical investigation of traditional herbal medicines holds significant promise for modern drug discovery,particularly in cancer therapy.This study aimed to evaluate the cytotoxicity,apoptosis induction,and immune-modulatory activities of extracts from three herbal medicines with historical use in traditional medicine—Acanthopanax sessiliflorus,Phragmites communis,and Pinus densiflora,as well as their combined extract(GMAS 01/COM),on human lung cancer cells(A549)and normal cell lines,including murine macrophages(RAW 264.7)and human keratinocytes(HaCaT).Methods:Plant extracts were prepared using aqueous extraction,sonication,and rotary evaporation.The total phenolic and flavonoid contents were quantified using the Folin-Ciocalteu and AlCl3 colorimetric methods,respectively.Antioxidant potential was evaluated via 2,2-Diphenyl-1-picrylhydrazyl(DPPH)scavenging and reducing power assays.Cytotoxicity was assessed using an MTT assay,while reactive oxygen species(ROS)generation was quantified using a 2′,7′-Dichlorodihydrofluorescein diacetate(DCFH-DA)assay.Anticancer properties,including colony formation inhibition and migration suppression,were examined using colony formation and wound healing assays.The expression of apoptotic and inflammatory mediators was analysed through qPCR.Results:GMAS 01 selectively induced apoptosis in A549 cells without cytotoxic effects on RAW264.7 and HaCaT cells.Mechanistically,it elevated intracellular ROS and activated the intrinsic mitochondrial apoptotic pathway,evidenced by p53 upregulation,increased Bax,and decreased Bcl-2 expression.GMAS 01 also significantly inhibited colony formation and migration in A549 cells.In RAW264.7 cells,it reduced nitric oxide(NO)production and downregulated iNOS,COX-2,IL-6,and IL-8,indicating strong immunomodulatory activity.Conclusion:GMAS 01 exhibits potent antioxidant,anti-inflammatory,and anticancer effects,likely mediated through ROS-induced mitochondrial apoptosis.However,mechanistic interpretations are limited by the absence of protein-level validation and pathway inhibition studies.Upcoming studies should aim to verify the underlying mechanisms and evaluate their potential for real-world application.展开更多
Neurodegenerative diseases(NDs)such as Alzheimer’s disease(AD),Parkinson’s disease(PD),Huntington’s disease(HD),and amyotrophic lateral sclerosis(ALS)are characterized by progressive neuronal loss,which is closely ...Neurodegenerative diseases(NDs)such as Alzheimer’s disease(AD),Parkinson’s disease(PD),Huntington’s disease(HD),and amyotrophic lateral sclerosis(ALS)are characterized by progressive neuronal loss,which is closely linked to mitochondrial dysfunction.These pathologies involve a complex interplay of genetics,protein misfolding,and cellular stress,culminating in impaired energy metabolism,an increase in reactive oxygen species(ROS),and defective mitochondrial quality control.The accumulation of damaged mitochondria and dysregulation of pathways such as the Integrated Stress Response(ISR)are central to the pathogenesis of these conditions.This review explores the critical relationship between mitochondrial stress and neurodegeneration,highlighting the molecular mechanisms and biomarkers involved.It delves into the multifaceted role of melatonin as a potent neuroprotective agent.Melatonin,a lipophilic indoleamine,is produced both in the pineal gland and locally within mitochondria,where it exerts powerful antioxidant,anti-inflammatory,and anti-apoptotic effects.Its unique ability to neutralize multiple free radicals and its cascade-based antioxidant action make it superior to conventional antioxidants.Its mechanisms of action are discussed,including signaling pathway modulation and enhancement of the brain’s clearance system(the glymphatic system).Despite its potential,melatonin’s low bioavailability and rapid metabolism limit its therapeutic efficacy.In this context,nanopharmacology emerges as a promising strategy.Nanoparticles such as liposomes,polymers,and solid lipids can encapsulate melatonin and protect it from degradation,facilitating its transport across the blood-brain barrier.Preclinical evidence has shown that melatonin-loaded nanoparticles significantly improve cognitive function,reduce oxidative stress,and restore mitochondrial homeostasis in models of AD,PD,and ALS.In conclusion,the synergistic combination of melatonin and nanopharmacology offers a multimodal and highly targeted approach formitigatingmitochondrial dysfunction in NDs.While challenges remain in optimizing the formulation and safety of these nanocarriers,this combination represents a crucial frontier for developing more effective and specific treatments in the future.展开更多
The question is asked whether soils can be regarded as extreme environments with respect to microorganisms. After defining some extreme environments in a general sense, special properties of extreme environments are c...The question is asked whether soils can be regarded as extreme environments with respect to microorganisms. After defining some extreme environments in a general sense, special properties of extreme environments are compared to soil habitats, with special emphasis laid on time frame and localities. In relation to water availability, nutrients and other properties, such places as aggregates can show properties of extreme habitats. These features, which can act at different levels of the system from the community level down to the cellular level, are summarized as stress factors. The latter,where many switches are located leading to different strategies of survival, is described as the most important one. This raises the question of how organisms have adapted to such conditions. The soil system demands a broad spectrum of adaptations and/or adjustments for a highly variable environment.The soil microorganisms'adaptation can thus be seen as the highest kind of flexibility and is more useful than any other special adaptation.展开更多
AIM： To identify multi-detector computed tomography （MDCT） features most predictive of serous cystadenomas （SCAs）, correlating with histopathology, and to study the impact of cyst size and MDCT technique on reade...AIM： To identify multi-detector computed tomography （MDCT） features most predictive of serous cystadenomas （SCAs）, correlating with histopathology, and to study the impact of cyst size and MDCT technique on reader performance. METHODS： The MDCT scans of 164 patients with surgically verified pancreatic cystic lesions were reviewed by two readers to study the predictive value of various morphological features for establishing a diagnosis of SCAs. Accuracy in lesion characterization and reader confidence were correlated with lesion size （≤3 cm or 〉≥3 cm） and scanning protocols （dedicated vs routine）. RESULTS： 28/164 cysts （mean size, 39 mm; range, 8-92 mm） were diagnosed as SCA on pathology. The MDCT features predictive of diagnosis of SCA were microcystic appearance （22/28, 78.6%）, surface Iobulations （25/28, 89.3%） and central scar （9/28, 32.4%）. Stepwise logistic regression analysis showed that only microcystic appearance was significant for CT diagnosis of SCA （P = 0.0001）. The sensitivity, specificity and PPV of central scar and of combined microcystic appearance and Iobulations were 32.4%/100%/100% and 68%/100%/100%, respectively. The reader confidence was higher for lesions 〉 3 cm （P = 0.02） and for MDCT scans performed using thin collimation （1.25-2.5 mm） compared to routine 5 mm collimation exams （P 〉 0.05）. CONCLUSION： Central scar on MDCT is diagnostic of SCA but is seen in only one third of SCAs. Microcystic morphology is the most significant CT feature in diagnosis of SCA. A combination of microcystic appearance and surface Iobulations offers accuracy comparable to central scar with higher sensitivity.展开更多
Magnesium alloys,as a new generation temporary biomaterial,deserve the desirable biocompatibility and biodegradability,and also contribute to the repair of the damaged bone tissues.However,they do not possess the requ...Magnesium alloys,as a new generation temporary biomaterial,deserve the desirable biocompatibility and biodegradability,and also contribute to the repair of the damaged bone tissues.However,they do not possess the required corrosion resistance in human body fluid.Hot mechanical workings,such as extrusion,influence both the mechanical properties and bio-corrosion behavior of magnesium alloys.This review aims to gather information on how the extrusion parameters(extrusion ratio and temperature)influence the bio-corrosion performances of magnesium alloys.Their effects are mainly ascribed to the alteration of extruded alloy microstructure,including final grain size and uniformity of grains,texture,and the size,distribution and volume fraction of the second phases.Dynamic recrystallization and grain refinement during extrusion provide a more homogeneous microstructure and cause the formation of basal texture,resulting in improved strength and corrosion resistance of magnesium alloy.Extrusion temperature and extrusion ratio are reported as the influential factors in the degradation.The reports reveal that the increase in extrusion ratio and/or the reduction in extrusion temperature cause a decrease in the final grain size,leading to intensification of basal texture,in parallel side of the samples with extrusion line,and to lower volume fraction and size of precipitates in magnesium alloys.These all lead to improving the bio-corrosion resistance of the magnesium alloy implants.展开更多
A hydrotreating NiMo/γ-Al2O3 catalyst(12 wt% Mo and 1.1 wt% Ni) was prepared by impregnation of the support with the Anderson-type heteropolyoxomolybdate(NH4)4Ni(OH)6Mo6O18.Before impregnation of the support,it was m...A hydrotreating NiMo/γ-Al2O3 catalyst(12 wt% Mo and 1.1 wt% Ni) was prepared by impregnation of the support with the Anderson-type heteropolyoxomolybdate(NH4)4Ni(OH)6Mo6O18.Before impregnation of the support,it was modified with an aqueous solution of H3BO3,Co(NO3)2,or Ni(NO3)2.The catalysts were investigated using N2 adsorption,O2 chemisorption,X-ray diffraction,UV-Vis spectroscopy,Fourier transform infrared spectroscopy,temperature-programmed reduction,temperature-programmed desorption,and X-ray photoelectron spectroscopy.The addition of Co,Ni,or B influenced the Al2O3 phase composition and gave increased catalytic activity for 1-benzothiophene hydrodesulfurization(HDS).X-ray photoelectron spectroscopy confirmed that the prior loading of Ni,Co or B increased the degree of sulfidation of the NiMo/γ-Al2O3 catalysts.The highest HDS activity was observed with the NiMo/γ-Al2O3 catalyst with prior loaded Ni.展开更多
基金funded by Korea Environmental Industry&Technology Institute(KEITI)through Wetland Ecosystem Value Evaluation and Carbon Absorption Value Promotion Technology Development Project of Korea Ministry of Environment(MOE)(RS-2022-KE002025).
文摘Urbanization and environmental degradation have led to significant declines in water quality and aquatic ecosystem health,highlighting the urgent need for effective restoration efforts.This study applies an integrated analysis approach to estimate the economic value and benefits of improvements in water quality and aquatic ecosystem services resulting from the Ecological Stream Restoration Project.Using survey data analyzed through the choice experiment(CE)method,we assessed respondents’preferences for various ecosystem services,including water-friendly services,ecological functions,water-level control,and water-quality purification.Three empirical analysis models—the Conditional Logit Model(CLM),Nested Logit Model(NL),and Error Component Logit Model(ECL)—were applied,with the ECL model identified as the most suitable for this study.From the physical impact assessment,we derived compensating variations to estimate the annual economic benefits of the project.The estimated annual economic value of water quality improvement due to the Anyangcheon Ecological Stream Restoration Project ranged from approximately KRW 10.54 billion to KRW 21.44 billion,while the economic value of aquatic ecosystem improvement was estimated to range from KRW 6.05 billion to KRW 12.30 billion annually.This study provides analytic framework that can inform future ecological restoration projects and sustainable water management policies.
基金funded by Korea Environmental Industry&Technology Institute(KEITI)through“Development of Aquatic Ecosystem Service Evaluation Indicators and Valuation Technology”of the Korea Ministry of Environment(MOE)(RS-2025-02214985).
文摘This study examines the empirical feasibility of quantitatively integrating environmental value information into Strategic Environmental Assessment(SEA).An analytical framework was established to incorporate environmental cost estimates into the SEA process by utilizing ecosystem service unit values provided by the Environmental Valuation Information System(EVIS),a national platform developed to support the evaluation of policies and projects.The framework was applied to a case study involving a multipurpose rural water development project in South Korea.Ecosystem service losses resulting from the project were quantified using biophysical indicators,such as vegetation biomass,forest area,and hydrological functions,and subsequently monetized through the application of the market price method,replacement cost method,and contingent valuation method.The total annual environmental cost was estimated to be approximately KRW 56.18 billion,with the majority attributable to losses in forest conservation and climate regulation services.These findings demonstrate that quantified environmental data can serve as a robust basis for alternative comparison and site evaluation within SEA.The study provides empirical evidence supporting the advancement of SEA from a predominantly procedural tool focused on environmental protection to a more comprehensive sustainability assessment framework that integrates environmental,economic,and social considerations.Furthermore,the results suggest that EVIS-based quantitative information holds potential for broader application in other national evaluation systems,such as preliminary feasibility studies and regulatory impact assessments.
文摘The electrocatalytic oxidation of glycerol toward formic acid is one of the most promising pathways for transformation and utilization of glycerol.Herein,a series of well-defined Ni_(n)(SR)_(2n) nanoclusters(n=4,5,6;denoted as Ni NCs)were prepared for the electrocatalytic glycerol oxidation toward formic acid,in which Ni_(6)-PET-50CV afforded the most excellent electrocatalytic performance with a high formic acid selectivity of 93% and a high glycerol conversion of 86%.This was attributed to the lowest charge transfer impedance and the most rapid reaction kinetics.Combined electrochemical measurements and X-ray absorption fine structure measurements revealed that the structures of Ni NCs remained intact after CV scanning pretreatment and electrocatalysis via forming the Ni–O bond.Additionally,the kinetic studies and in-situ Fourier transformed infrared suggested a sequential oxidation mechanism,in which the main reaction steps of glycerol→glyceraldehyde→glyceric acid were very rapid to produce a high selectivity of formic acid even though the low glycerol conversion.This work presents an opportunity to study Ni NCs for the efficient electrocatalytic oxidation of biomass-derived polyhydroxyl platform molecules to produce value-added carboxylic acids.
基金the Russian Science Foundation Project No.22-79-10286,https://rscf.ru/project/22-7910286/(synthesis of perovskites, PeLEC fabrication)the Russian Science Foundation Project No.23-79-01151 for NW/PDMS membrane fabrication and PeLEC characterization+1 种基金the Ministry of Science and Higher Education of the Russian Federation (Project. FZSR-2020-0007 within the framework of state task no. 075-03-2020-097/1) for the support of SWCNT synthesisthe Ministry of Science and Higher Education of the Russian Federation (Project FSRM-2022-0007) for NW fabrication
文摘The emergence of cesium lead halide perovskite materials stable at air opened new prospects for the optoelectronic industry.In this work we present an approach to fabricating a flexible green perovskite light-emitting electrochemical cell(PeLEC)with a CsPbBr_(3)perovskite active layer using a highly-ordered silicon nanowire(Si NW)array as a distributed electrode integrated within a thin polydimethylsiloxane film(PDMS).Numerical simulations reveal that Si NWs-based distributed electrode aids the improvement of carrier injection into the perovskite layer with an increased thickness and,therefore,the enhancement of light-emitting performance.The X-ray diffraction study shows that the perovskite layer synthesized on the PDMS membrane with Si NWs has a similar crystal structure to the ones synthesized on planar Si wafers.We perform a comparative analysis of the light-emitting devices’properties fabricated on rigid silicon substrates and flexible Si NW-based membranes released from substrates.Due to possible potential barriers in a flexible PeLEC between the bottom electrode(made of a network of single-walled carbon nanotube film)and Si NWs,the electroluminescence performance and Ⅰ-V properties of flexible devices deteriorated compared to rigid devices.The developed PeLECs pave the way for further development of inorganic flexible uniformly light-emitting devices with improved properties.
基金supported by a grant from the Singer Biology Fund at the University of Florida。
文摘Olfactory receptors(ORs),the largest vertebrate multigene family,exhibit wide copy number variation among taxa,ranging from~100 to 4000.The ecological importance of smell has been suggested to positively correlate with OR gene number,though debate exists on whether the number of total ORs,functional ORs,or the percentage of pseudogenes matters most.While olfaction has been poorly studied in most birds,Turkey Vultures(Cathartes aura)demonstrate keen olfactory ability,capable of foraging using smell alone.In contrast,Black Vultures(Coragyps atratus)have been thought to primarily use vision to locate food.Comparison of the OR genes in these two New World vultures presents an opportunity to examine the dynamics of OR evolution in related avian species that may differ in olfactory abilities.Using a PCR and cloning approach with degenerate primers,we sampled the OR subgenome in Turkey and Black Vultures,as well as Red-tailed Hawks(Buteo jamaicensis)and the distantly related Chicken(Gallus gallus),neither of which are thought to use olfaction extensively.Our results indicate that Turkey Vultures have many more OR genes than Red-tailed Hawks or chickens.Surprisingly,Black Vultures had an intermediate number of OR genes.The number of OR genes we estimated in the Turkey Vulture was much greater than previously reported in studies that used short-read sequencing.Additionally,we found that OR genes from New World vultures and Red-tailed Hawks form clades that were distinct from the clade that included most chicken OR genes,indicating that chickens share few OR orthologs with New World vultures or hawks.As previously observed in other animal groups,pseudogenes appeared throughout all clades and their percentage varied among taxa.These findings suggest the OR gene family is highly dynamic,changing rapidly over evolutionary time,and that taxa may have distinct suites of ORs in their genomes.
文摘Objectives:The phytochemical investigation of traditional herbal medicines holds significant promise for modern drug discovery,particularly in cancer therapy.This study aimed to evaluate the cytotoxicity,apoptosis induction,and immune-modulatory activities of extracts from three herbal medicines with historical use in traditional medicine—Acanthopanax sessiliflorus,Phragmites communis,and Pinus densiflora,as well as their combined extract(GMAS 01/COM),on human lung cancer cells(A549)and normal cell lines,including murine macrophages(RAW 264.7)and human keratinocytes(HaCaT).Methods:Plant extracts were prepared using aqueous extraction,sonication,and rotary evaporation.The total phenolic and flavonoid contents were quantified using the Folin-Ciocalteu and AlCl3 colorimetric methods,respectively.Antioxidant potential was evaluated via 2,2-Diphenyl-1-picrylhydrazyl(DPPH)scavenging and reducing power assays.Cytotoxicity was assessed using an MTT assay,while reactive oxygen species(ROS)generation was quantified using a 2′,7′-Dichlorodihydrofluorescein diacetate(DCFH-DA)assay.Anticancer properties,including colony formation inhibition and migration suppression,were examined using colony formation and wound healing assays.The expression of apoptotic and inflammatory mediators was analysed through qPCR.Results:GMAS 01 selectively induced apoptosis in A549 cells without cytotoxic effects on RAW264.7 and HaCaT cells.Mechanistically,it elevated intracellular ROS and activated the intrinsic mitochondrial apoptotic pathway,evidenced by p53 upregulation,increased Bax,and decreased Bcl-2 expression.GMAS 01 also significantly inhibited colony formation and migration in A549 cells.In RAW264.7 cells,it reduced nitric oxide(NO)production and downregulated iNOS,COX-2,IL-6,and IL-8,indicating strong immunomodulatory activity.Conclusion:GMAS 01 exhibits potent antioxidant,anti-inflammatory,and anticancer effects,likely mediated through ROS-induced mitochondrial apoptosis.However,mechanistic interpretations are limited by the absence of protein-level validation and pathway inhibition studies.Upcoming studies should aim to verify the underlying mechanisms and evaluate their potential for real-world application.
文摘Neurodegenerative diseases(NDs)such as Alzheimer’s disease(AD),Parkinson’s disease(PD),Huntington’s disease(HD),and amyotrophic lateral sclerosis(ALS)are characterized by progressive neuronal loss,which is closely linked to mitochondrial dysfunction.These pathologies involve a complex interplay of genetics,protein misfolding,and cellular stress,culminating in impaired energy metabolism,an increase in reactive oxygen species(ROS),and defective mitochondrial quality control.The accumulation of damaged mitochondria and dysregulation of pathways such as the Integrated Stress Response(ISR)are central to the pathogenesis of these conditions.This review explores the critical relationship between mitochondrial stress and neurodegeneration,highlighting the molecular mechanisms and biomarkers involved.It delves into the multifaceted role of melatonin as a potent neuroprotective agent.Melatonin,a lipophilic indoleamine,is produced both in the pineal gland and locally within mitochondria,where it exerts powerful antioxidant,anti-inflammatory,and anti-apoptotic effects.Its unique ability to neutralize multiple free radicals and its cascade-based antioxidant action make it superior to conventional antioxidants.Its mechanisms of action are discussed,including signaling pathway modulation and enhancement of the brain’s clearance system(the glymphatic system).Despite its potential,melatonin’s low bioavailability and rapid metabolism limit its therapeutic efficacy.In this context,nanopharmacology emerges as a promising strategy.Nanoparticles such as liposomes,polymers,and solid lipids can encapsulate melatonin and protect it from degradation,facilitating its transport across the blood-brain barrier.Preclinical evidence has shown that melatonin-loaded nanoparticles significantly improve cognitive function,reduce oxidative stress,and restore mitochondrial homeostasis in models of AD,PD,and ALS.In conclusion,the synergistic combination of melatonin and nanopharmacology offers a multimodal and highly targeted approach formitigatingmitochondrial dysfunction in NDs.While challenges remain in optimizing the formulation and safety of these nanocarriers,this combination represents a crucial frontier for developing more effective and specific treatments in the future.
文摘The question is asked whether soils can be regarded as extreme environments with respect to microorganisms. After defining some extreme environments in a general sense, special properties of extreme environments are compared to soil habitats, with special emphasis laid on time frame and localities. In relation to water availability, nutrients and other properties, such places as aggregates can show properties of extreme habitats. These features, which can act at different levels of the system from the community level down to the cellular level, are summarized as stress factors. The latter,where many switches are located leading to different strategies of survival, is described as the most important one. This raises the question of how organisms have adapted to such conditions. The soil system demands a broad spectrum of adaptations and/or adjustments for a highly variable environment.The soil microorganisms'adaptation can thus be seen as the highest kind of flexibility and is more useful than any other special adaptation.
文摘AIM： To identify multi-detector computed tomography （MDCT） features most predictive of serous cystadenomas （SCAs）, correlating with histopathology, and to study the impact of cyst size and MDCT technique on reader performance. METHODS： The MDCT scans of 164 patients with surgically verified pancreatic cystic lesions were reviewed by two readers to study the predictive value of various morphological features for establishing a diagnosis of SCAs. Accuracy in lesion characterization and reader confidence were correlated with lesion size （≤3 cm or 〉≥3 cm） and scanning protocols （dedicated vs routine）. RESULTS： 28/164 cysts （mean size, 39 mm; range, 8-92 mm） were diagnosed as SCA on pathology. The MDCT features predictive of diagnosis of SCA were microcystic appearance （22/28, 78.6%）, surface Iobulations （25/28, 89.3%） and central scar （9/28, 32.4%）. Stepwise logistic regression analysis showed that only microcystic appearance was significant for CT diagnosis of SCA （P = 0.0001）. The sensitivity, specificity and PPV of central scar and of combined microcystic appearance and Iobulations were 32.4%/100%/100% and 68%/100%/100%, respectively. The reader confidence was higher for lesions 〉 3 cm （P = 0.02） and for MDCT scans performed using thin collimation （1.25-2.5 mm） compared to routine 5 mm collimation exams （P 〉 0.05）. CONCLUSION： Central scar on MDCT is diagnostic of SCA but is seen in only one third of SCAs. Microcystic morphology is the most significant CT feature in diagnosis of SCA. A combination of microcystic appearance and surface Iobulations offers accuracy comparable to central scar with higher sensitivity.
文摘Magnesium alloys,as a new generation temporary biomaterial,deserve the desirable biocompatibility and biodegradability,and also contribute to the repair of the damaged bone tissues.However,they do not possess the required corrosion resistance in human body fluid.Hot mechanical workings,such as extrusion,influence both the mechanical properties and bio-corrosion behavior of magnesium alloys.This review aims to gather information on how the extrusion parameters(extrusion ratio and temperature)influence the bio-corrosion performances of magnesium alloys.Their effects are mainly ascribed to the alteration of extruded alloy microstructure,including final grain size and uniformity of grains,texture,and the size,distribution and volume fraction of the second phases.Dynamic recrystallization and grain refinement during extrusion provide a more homogeneous microstructure and cause the formation of basal texture,resulting in improved strength and corrosion resistance of magnesium alloy.Extrusion temperature and extrusion ratio are reported as the influential factors in the degradation.The reports reveal that the increase in extrusion ratio and/or the reduction in extrusion temperature cause a decrease in the final grain size,leading to intensification of basal texture,in parallel side of the samples with extrusion line,and to lower volume fraction and size of precipitates in magnesium alloys.These all lead to improving the bio-corrosion resistance of the magnesium alloy implants.
基金supported by the Czech Science Foundation (P106/11/0902)Scientific Cooperation Funds of Bulgarian and Czech Academies
文摘A hydrotreating NiMo/γ-Al2O3 catalyst(12 wt% Mo and 1.1 wt% Ni) was prepared by impregnation of the support with the Anderson-type heteropolyoxomolybdate(NH4)4Ni(OH)6Mo6O18.Before impregnation of the support,it was modified with an aqueous solution of H3BO3,Co(NO3)2,or Ni(NO3)2.The catalysts were investigated using N2 adsorption,O2 chemisorption,X-ray diffraction,UV-Vis spectroscopy,Fourier transform infrared spectroscopy,temperature-programmed reduction,temperature-programmed desorption,and X-ray photoelectron spectroscopy.The addition of Co,Ni,or B influenced the Al2O3 phase composition and gave increased catalytic activity for 1-benzothiophene hydrodesulfurization(HDS).X-ray photoelectron spectroscopy confirmed that the prior loading of Ni,Co or B increased the degree of sulfidation of the NiMo/γ-Al2O3 catalysts.The highest HDS activity was observed with the NiMo/γ-Al2O3 catalyst with prior loaded Ni.
