Chemical warfare agents(CWAs)remain a persistent hazard in many parts of the world,necessitating a deeper exploration of their chemical and physical characteristics and reactions under diverse conditions.Diisopropyl m...Chemical warfare agents(CWAs)remain a persistent hazard in many parts of the world,necessitating a deeper exploration of their chemical and physical characteristics and reactions under diverse conditions.Diisopropyl methylphosphonate(DIMP),a commonly used CWA surrogate,is widely studied to enhance our understanding of CWA behavior.The prevailing thermal decomposition model for DIMP,developed approximately 25 years ago,is based on data collected in nitrogen atmospheres at temperatures ranging from 700 K to 800 K.Despite its limitations,this model continues to serve as a foundation for research across various thermal and reactive environments,including combustion studies.Our recent experiments have extended the scope of decomposition analysis by examining DIMP in both nitrogen and zero air across a lower temperature range of 175??C to 250??C.Infrared spectroscopy results under nitrogen align well with the established model;however,we observed that catalytic effects,stemming from decomposition byproducts and interactions with stainless steel surfaces,alter the reaction kinetics.In zero air environments,we observed a novel infrared absorption band.Spectral fitting suggests this band may represent a combination of propanal and acetone,while GCMS analysis points to vinyl formate and acetone as possible constituents.Although the precise identity of these new products remains unresolved,our findings clearly indicate that the existing decomposition model cannot be reliably extended to lower temperatures or non-nitrogen environments without further revisions.展开更多
During a toxicological test using diisopropyl methylphosphonate (DIMP) on mallards, an anaesthesia-like response was noted after oral dosing. In order to further elucidate these effects, arterial blood pressures were ...During a toxicological test using diisopropyl methylphosphonate (DIMP) on mallards, an anaesthesia-like response was noted after oral dosing. In order to further elucidate these effects, arterial blood pressures were determined both pre-and post-dosing on adit male and female mallards by cannulation of the left carotid artery. A significant decrease in systolic, diastolic, and mean blood pressure was noted after the oral administration of DIMP. There was no significant difference in response between males and females. During the first 30 min after dosing, systolic pressure fell from an average of 158 mmHg, to 94 mmHg, diastolic decreased from 127 mmHg to 63 mmHg, and mean blood pressure dropped from 138 mmHg to 75 mmHg. However, there was no significant effect on pulse pressure, heart rate, or respiratory rate. These results are compared to physiological data cited in the literature for various CNS-acting drugs on mallards.展开更多
Microbial degradation of methylphosphonate(MPn)is an important pathway contributing to the‘methane paradox’in the oxic ocean.Vibrio spp.are suggested to participate in this process.However,little is known about the ...Microbial degradation of methylphosphonate(MPn)is an important pathway contributing to the‘methane paradox’in the oxic ocean.Vibrio spp.are suggested to participate in this process.However,little is known about the molecular basis,phy-logenetic breadth and catabolic efficiency of methane production in Vibrio species.Here,18 Vibrionales strains known to be effective in MPn demethylation were obtained.The most effective strains,i.e.,Vibrio gallaecicus HW2-07 and HW2-08,can convert 70%-80%of amended MPn into methane in 5 days.Estimations based on quantitative PCR determination indicated that Vibrio spp.were influential contributors to marine methane production.Genes flanking the common phn genes suggested a divergent gene arrangement and grouped the phn operons into nine types.This was consistent with the phylogeny of phnJ and phnL.The phn operons of cluster I and II were identified frequently in Vibrio isolates and were common in coastal seas and the open ocean.Addition of MPn increased expression of the phn genes,as well as an unexpected gene that encodes an acyltransferase(act),which frequently occurred in cluster I-IV operons.This study provided experimental evidence and theo-retical support for a further understanding that Vibrio spp.may play important roles in aerobic marine methane production.展开更多
The process of neurite outgrowth and branching is a crucial aspect of neuronal development and regeneration.Axons and dendrites,sometimes referred to as neurites,are extensions of a neuron's cellular body that are...The process of neurite outgrowth and branching is a crucial aspect of neuronal development and regeneration.Axons and dendrites,sometimes referred to as neurites,are extensions of a neuron's cellular body that are used to start networks.Here we explored the effects of diethyl(3,4-dihydroxyphenethylamino)(quinolin-4-yl)methylphosphonate(DDQ)on neurite developmental features in HT22 neuronal cells.In this work,we examined the protective effects of DDQ on neuronal processes and synaptic outgrowth in differentiated HT22cells expressing mutant Tau(mTau)cDNA.To investigate DDQ chara cteristics,cell viability,biochemical,molecular,western blotting,and immunocytochemistry were used.Neurite outgrowth is evaluated through the segmentation and measurement of neural processes.These neural processes can be seen and measured with a fluorescence microscope by manually tracing and measuring the length of the neurite growth.These neuronal processes can be observed and quantified with a fluorescent microscope by manually tracing and measuring the length of the neuronal HT22.DDQ-treated mTau-HT22 cells(HT22 cells transfected with cDNA mutant Tau)were seen to display increased levels of synaptophysin,MAP-2,andβ-tubulin.Additionally,we confirmed and noted reduced levels of both total and p-Tau,as well as elevated levels of microtubule-associated protein 2,β-tubulin,synaptophysin,vesicular acetylcholine transporter,and the mitochondrial biogenesis protein-pe roxisome prolife rator-activated receptor-gamma coactivator-1α.In mTa u-expressed HT22 neurons,we observed DDQ enhanced the neurite characteristics and improved neurite development through increased synaptic outgrowth.Our findings conclude that mTa u-HT22(Alzheimer's disease)cells treated with DDQ have functional neurite developmental chara cteristics.The key finding is that,in mTa u-HT22 cells,DDQ preserves neuronal structure and may even enhance nerve development function with mTa u inhibition.展开更多
Accurate detection of dimethyl methylphosphonate(DMMP),a simulant for chemical warfare agents,is vital for both public safety and military defense.However,conventional detection methods suffer from low selectivity,owi...Accurate detection of dimethyl methylphosphonate(DMMP),a simulant for chemical warfare agents,is vital for both public safety and military defense.However,conventional detection methods suffer from low selectivity,owing to interference from structurally similar compounds.In this study,we present a highly sensitive and selective gas sensor utilizing a solid-mounted film bulk acoustic resonator based on carbon nanotubes functionalized with hexafluoroisopropanol(HFiP)to enhance DMMP detection.This approach leverages the strong hydrogen bonding between HFiP and DMMP molecules to significantly improve the sensor’s adsorption capacity and selectivity.To further refine selectivity and at the same time solve the cross-sensitivity problem of sensitive membranes,we introduce a virtual sensor array design,generated by modulating the input power to the resonator,which enables the sensor to operate in multiple response modes across varying vibrational amplitudes.These multimodal responses are subjected to linear discriminant analysis,allowing precise differentiation of DMMP from other volatile organic compounds such as tributyl phosphate and dimethyl phthalate.Our results demonstrate superior performance in terms of both sensitivity and selectivity,offering a robust solution for detecting low-concentration DMMP in complex environments.展开更多
The optimum conditions for extraction-chromatography using di-(l-methylheptyl) methylphosphonate resin to separate indium(Ⅲ) from its coexisting metal ions were studied. A procedure for extraction- chromatographic se...The optimum conditions for extraction-chromatography using di-(l-methylheptyl) methylphosphonate resin to separate indium(Ⅲ) from its coexisting metal ions were studied. A procedure for extraction- chromatographic separation and spectrophotometric determination of indium has been developed. This proce- dure gives more clear-cut separation and higher accuracy and reproducibility than ordinarily used separation by solvent extraction with butyl acetate. Besides, it can be used to separate and determine cadmium simultaneously.展开更多
The destruction of methylphosphonic acid （MPA）, a final product by hydrolysis/neutralization of organophosphorus agents such as sarin and VX （O-ethyl S-[2-（diisopropylamino）ethyl] methylphosphonothionate）, was i...The destruction of methylphosphonic acid （MPA）, a final product by hydrolysis/neutralization of organophosphorus agents such as sarin and VX （O-ethyl S-[2-（diisopropylamino）ethyl] methylphosphonothionate）, was investigated in a a bench-scale, continuous concentric vertical double wall reactor under supercritical water oxidation condition. The experiments were conducted at a temperature range of 450–600°C and a fixed pressure of 25 MPa. Hydrogen peroxide was used as an oxidant. The destruction efficiency （DE） was monitored by analyzing total organic carbon （TOC） and MPA concentrations using ion chromatography on the liquid effluent samples. The results showed that the DE of MPA up to 99.999% was achieved at a reaction temperature of 600°C, oxygen concentration of 113% storichiometric requirement, and reactor residence time of 8 sec. On the basis of the data derived from experiments, a global kinetic rate equation for the DE of MPA and DE of TOC were developed by nonlinear regression analysis. The model predictions agreed well with the experimental data.展开更多
The global warming potential of methane(CH_4) is about 30 times stronger than that of carbon dioxide(CO2) over a century timescale. Methane emission is hypothesized to have contributed to global climate change events ...The global warming potential of methane(CH_4) is about 30 times stronger than that of carbon dioxide(CO2) over a century timescale. Methane emission is hypothesized to have contributed to global climate change events and mass extinctions during Earth's history. Therefore, the study of CH_4 production processes is critically important to the understanding of global climate change. It has been a dogma that biogenic CH_4 detectable in the oceans originates exclusively from the anaerobic metabolic activity of methanogenic archaea in hypoxic and anoxic environments, despite reports that many oxic surface and near-surface waters of the world's oceans are CH_4-supersaturated, thereby rendering net sea-to-air emissions of CH_4. The phenomenon of CH_4 production in oxic marine waters is referred to as the "ocean methane paradox". Although still not totally resolved, recent studies have generated several hypotheses regarding the sources of CH_4 production in oxic seawater. This review will summarize our current understanding of the importance of CH_4 in the global climate and analyze the biological processes and their underpinning mechanisms that lead to the production of CH_4 in oxic seawater environments. We will also tentatively explore the relationships of these microbial metabolic processes with global changes in climate and environment.展开更多
基金sponsored by the Department of Defense,Defense Threat Reduction Agency under the Materials Science in Extreme Environments University Research Alliance,HDTRA1-20-2-0001。
文摘Chemical warfare agents(CWAs)remain a persistent hazard in many parts of the world,necessitating a deeper exploration of their chemical and physical characteristics and reactions under diverse conditions.Diisopropyl methylphosphonate(DIMP),a commonly used CWA surrogate,is widely studied to enhance our understanding of CWA behavior.The prevailing thermal decomposition model for DIMP,developed approximately 25 years ago,is based on data collected in nitrogen atmospheres at temperatures ranging from 700 K to 800 K.Despite its limitations,this model continues to serve as a foundation for research across various thermal and reactive environments,including combustion studies.Our recent experiments have extended the scope of decomposition analysis by examining DIMP in both nitrogen and zero air across a lower temperature range of 175??C to 250??C.Infrared spectroscopy results under nitrogen align well with the established model;however,we observed that catalytic effects,stemming from decomposition byproducts and interactions with stainless steel surfaces,alter the reaction kinetics.In zero air environments,we observed a novel infrared absorption band.Spectral fitting suggests this band may represent a combination of propanal and acetone,while GCMS analysis points to vinyl formate and acetone as possible constituents.Although the precise identity of these new products remains unresolved,our findings clearly indicate that the existing decomposition model cannot be reliably extended to lower temperatures or non-nitrogen environments without further revisions.
文摘During a toxicological test using diisopropyl methylphosphonate (DIMP) on mallards, an anaesthesia-like response was noted after oral dosing. In order to further elucidate these effects, arterial blood pressures were determined both pre-and post-dosing on adit male and female mallards by cannulation of the left carotid artery. A significant decrease in systolic, diastolic, and mean blood pressure was noted after the oral administration of DIMP. There was no significant difference in response between males and females. During the first 30 min after dosing, systolic pressure fell from an average of 158 mmHg, to 94 mmHg, diastolic decreased from 127 mmHg to 63 mmHg, and mean blood pressure dropped from 138 mmHg to 75 mmHg. However, there was no significant effect on pulse pressure, heart rate, or respiratory rate. These results are compared to physiological data cited in the literature for various CNS-acting drugs on mallards.
基金funded by the National Natural Science Foundation of China(41730530 and 42206088)the National Key Research and Devel-opment Program of China(2018YFE0124100)+1 种基金the Fundamental Research Funds for the Central Universities(202172002)the China Postdoctoral Science Foundation(2022M722977).
文摘Microbial degradation of methylphosphonate(MPn)is an important pathway contributing to the‘methane paradox’in the oxic ocean.Vibrio spp.are suggested to participate in this process.However,little is known about the molecular basis,phy-logenetic breadth and catabolic efficiency of methane production in Vibrio species.Here,18 Vibrionales strains known to be effective in MPn demethylation were obtained.The most effective strains,i.e.,Vibrio gallaecicus HW2-07 and HW2-08,can convert 70%-80%of amended MPn into methane in 5 days.Estimations based on quantitative PCR determination indicated that Vibrio spp.were influential contributors to marine methane production.Genes flanking the common phn genes suggested a divergent gene arrangement and grouped the phn operons into nine types.This was consistent with the phylogeny of phnJ and phnL.The phn operons of cluster I and II were identified frequently in Vibrio isolates and were common in coastal seas and the open ocean.Addition of MPn increased expression of the phn genes,as well as an unexpected gene that encodes an acyltransferase(act),which frequently occurred in cluster I-IV operons.This study provided experimental evidence and theo-retical support for a further understanding that Vibrio spp.may play important roles in aerobic marine methane production.
基金supported by NIH grants AG079264(to PHR)and AG071560(to APR)。
文摘The process of neurite outgrowth and branching is a crucial aspect of neuronal development and regeneration.Axons and dendrites,sometimes referred to as neurites,are extensions of a neuron's cellular body that are used to start networks.Here we explored the effects of diethyl(3,4-dihydroxyphenethylamino)(quinolin-4-yl)methylphosphonate(DDQ)on neurite developmental features in HT22 neuronal cells.In this work,we examined the protective effects of DDQ on neuronal processes and synaptic outgrowth in differentiated HT22cells expressing mutant Tau(mTau)cDNA.To investigate DDQ chara cteristics,cell viability,biochemical,molecular,western blotting,and immunocytochemistry were used.Neurite outgrowth is evaluated through the segmentation and measurement of neural processes.These neural processes can be seen and measured with a fluorescence microscope by manually tracing and measuring the length of the neurite growth.These neuronal processes can be observed and quantified with a fluorescent microscope by manually tracing and measuring the length of the neuronal HT22.DDQ-treated mTau-HT22 cells(HT22 cells transfected with cDNA mutant Tau)were seen to display increased levels of synaptophysin,MAP-2,andβ-tubulin.Additionally,we confirmed and noted reduced levels of both total and p-Tau,as well as elevated levels of microtubule-associated protein 2,β-tubulin,synaptophysin,vesicular acetylcholine transporter,and the mitochondrial biogenesis protein-pe roxisome prolife rator-activated receptor-gamma coactivator-1α.In mTa u-expressed HT22 neurons,we observed DDQ enhanced the neurite characteristics and improved neurite development through increased synaptic outgrowth.Our findings conclude that mTa u-HT22(Alzheimer's disease)cells treated with DDQ have functional neurite developmental chara cteristics.The key finding is that,in mTa u-HT22 cells,DDQ preserves neuronal structure and may even enhance nerve development function with mTa u inhibition.
基金supported by the State Key Laboratory of Pathogens and Biosecurity(Grant No.SKLPBS2240).
文摘Accurate detection of dimethyl methylphosphonate(DMMP),a simulant for chemical warfare agents,is vital for both public safety and military defense.However,conventional detection methods suffer from low selectivity,owing to interference from structurally similar compounds.In this study,we present a highly sensitive and selective gas sensor utilizing a solid-mounted film bulk acoustic resonator based on carbon nanotubes functionalized with hexafluoroisopropanol(HFiP)to enhance DMMP detection.This approach leverages the strong hydrogen bonding between HFiP and DMMP molecules to significantly improve the sensor’s adsorption capacity and selectivity.To further refine selectivity and at the same time solve the cross-sensitivity problem of sensitive membranes,we introduce a virtual sensor array design,generated by modulating the input power to the resonator,which enables the sensor to operate in multiple response modes across varying vibrational amplitudes.These multimodal responses are subjected to linear discriminant analysis,allowing precise differentiation of DMMP from other volatile organic compounds such as tributyl phosphate and dimethyl phthalate.Our results demonstrate superior performance in terms of both sensitivity and selectivity,offering a robust solution for detecting low-concentration DMMP in complex environments.
文摘The optimum conditions for extraction-chromatography using di-(l-methylheptyl) methylphosphonate resin to separate indium(Ⅲ) from its coexisting metal ions were studied. A procedure for extraction- chromatographic separation and spectrophotometric determination of indium has been developed. This proce- dure gives more clear-cut separation and higher accuracy and reproducibility than ordinarily used separation by solvent extraction with butyl acetate. Besides, it can be used to separate and determine cadmium simultaneously.
基金supported by Agency for Defense Development,Korea and Korea Institute of Scienceand Technology
文摘The destruction of methylphosphonic acid （MPA）, a final product by hydrolysis/neutralization of organophosphorus agents such as sarin and VX （O-ethyl S-[2-（diisopropylamino）ethyl] methylphosphonothionate）, was investigated in a a bench-scale, continuous concentric vertical double wall reactor under supercritical water oxidation condition. The experiments were conducted at a temperature range of 450–600°C and a fixed pressure of 25 MPa. Hydrogen peroxide was used as an oxidant. The destruction efficiency （DE） was monitored by analyzing total organic carbon （TOC） and MPA concentrations using ion chromatography on the liquid effluent samples. The results showed that the DE of MPA up to 99.999% was achieved at a reaction temperature of 600°C, oxygen concentration of 113% storichiometric requirement, and reactor residence time of 8 sec. On the basis of the data derived from experiments, a global kinetic rate equation for the DE of MPA and DE of TOC were developed by nonlinear regression analysis. The model predictions agreed well with the experimental data.
基金supported by the National Key Research and Development Program of China (Grant No. 2016YFA0601303)the Chinese State Oceanic Administration (SOA) (Grant No. GASI-03-01-02-05)+1 种基金the National Natural Science Foundation of China (Grant Nos. 41676122, 91328209 & 91428308)the China National Offshore Oil Corporation (Grant Nos. CNOOC-KJ125FZDXM00TJ0012014 & CNOOC-KJ125FZDXM00ZJ001-2014)
文摘The global warming potential of methane(CH_4) is about 30 times stronger than that of carbon dioxide(CO2) over a century timescale. Methane emission is hypothesized to have contributed to global climate change events and mass extinctions during Earth's history. Therefore, the study of CH_4 production processes is critically important to the understanding of global climate change. It has been a dogma that biogenic CH_4 detectable in the oceans originates exclusively from the anaerobic metabolic activity of methanogenic archaea in hypoxic and anoxic environments, despite reports that many oxic surface and near-surface waters of the world's oceans are CH_4-supersaturated, thereby rendering net sea-to-air emissions of CH_4. The phenomenon of CH_4 production in oxic marine waters is referred to as the "ocean methane paradox". Although still not totally resolved, recent studies have generated several hypotheses regarding the sources of CH_4 production in oxic seawater. This review will summarize our current understanding of the importance of CH_4 in the global climate and analyze the biological processes and their underpinning mechanisms that lead to the production of CH_4 in oxic seawater environments. We will also tentatively explore the relationships of these microbial metabolic processes with global changes in climate and environment.
