Organophosphorus pesticides(OPPs)in foods pose a serious threat to human health,motivating the development of novel analytical methods for their rapid detection and quantification.A magnetic covalent organic framework...Organophosphorus pesticides(OPPs)in foods pose a serious threat to human health,motivating the development of novel analytical methods for their rapid detection and quantification.A magnetic covalent organic framework(M-COF)adsorbent for the magnetic solid-phase extraction(MSPE)of OPPs from foods was reported.M-COF was synthesized by the Schiff base condensation reaction of 1,3,5-tris(4-aminophenyl)benzene and 4,4-biphenyldicarboxaldehyde on the surface of amino-functionalized magnetic nanoparticles.Density functional theory(DFT)calculations showed that adsorption of OPPs onto the surface of M-COF involved hydrophobic effects,van der Waals interactions,π-πinteractions,halogen-N bonding,and hydrogen bonding.Combined with gas chromatography-mass spectrometry(GC-MS)technology,the MSPE method features low limits of detection for OPPs(0.002-0.015μg/L),good reproducibility(1.45%-6.14%),wide linear detection range(0.01-1μg/L,R≥0.9935),and satisfactory recoveries(87.3%-110.4%).The method was successfully applied for the trace analysis of OPPs in spiked fruit juices.展开更多
The Nano-Micro Letters(2024)16:193,article by Shangguan et al.,entitled“Making the Complicated Simple:A Minimizing Carrier Strategy on Innovative Nanopesticides”(Nano-Micro Lett.https://doi.org/10.1007/s40820-024-01...The Nano-Micro Letters(2024)16:193,article by Shangguan et al.,entitled“Making the Complicated Simple:A Minimizing Carrier Strategy on Innovative Nanopesticides”(Nano-Micro Lett.https://doi.org/10.1007/s40820-024-01413-5),was published online on 14 May,2024,with errors.The structural formulas and captions of the three acyl chlorides in Fig.3A were wrong.They should be as shown below.展开更多
BACKGROUND:Penehyclidine is a newly developed anticholinergic agent.We aimed to investigate the role of penehyclidine in acute organophosphorus pesticide poisoning(OP)patients.METHODS:We searched the Pubmed,Cochrane l...BACKGROUND:Penehyclidine is a newly developed anticholinergic agent.We aimed to investigate the role of penehyclidine in acute organophosphorus pesticide poisoning(OP)patients.METHODS:We searched the Pubmed,Cochrane library,EMBASE,Chinese National Knowledge Infrastructure(CNKI),Chinese Biomedical literature(CBM)and Wanfang databases.Randomized controlled trials(RCTs)recruiting acute OP patients were identifi ed for meta-analysis.Main outcomes included cure rate,mortality rate,time to atropinization,time to 60%normal acetylcholinesterase(AchE)level,rate of intermediate syndrome(IMS)and rate of adverse drug reactions(ADR).RESULTS:Sixteen RCTs involving 1,334 patients were identifi ed.Compared with the atropineor penehyclidine-alone groups,atropine combined with penehyclidine significantly increased the cure rate(penehyclidine+atropine vs.atropine,0.97 vs.0.86,RR 1.13,95%CI[1.07–1.19];penehyclidine+atropine vs.penehyclidine,0.93 vs.0.80,RR 1.08,95%CI[1.01–1.15])and reduced the mortality rate(penehyclidine+atropine vs.atropine,0.015 vs.0.11,RR 0.17,95%CI[0.06–0.49];penehyclidine+atropine vs.penehyclidine,0.13 vs.0.08,RR 0.23,95%CI[0.04–1.28]).Atropine combined with penehyclidine in OP patients also helped reduce the time to atropinization and AchE recovery,the rate of IMS and the rate of ADR.Compared with a single dose of atropine,a single dose of penehyclidine also signifi cantly elevated the cure rate,reduced times to atropinization,AchE recovery,and rate of IMS.CONCLUSION:Atropine combined with penehyclidine benefi ts OP patients by enhancing the cure rate,mortality rate,time to atropinization,AchE recovery,IMS rate,total ADR and duration of hospitalization.Penehyclidine combined with atropine is likely a better initial therapy for OP patients than atropine alone.展开更多
This study established a method for the simultaneous determination of 74 pesticide residues in Panax notoginseng by QuEChERS pretreatment method coupled with GC-MS/MS,and carried out pesticide residue analysis on 20 b...This study established a method for the simultaneous determination of 74 pesticide residues in Panax notoginseng by QuEChERS pretreatment method coupled with GC-MS/MS,and carried out pesticide residue analysis on 20 batches of market samples in China.The samples were extracted with acetonitrile,cleaned up with primary secondary amine(PSA)and octadecylsilane(C18)and determined by GC-MS/MS in multiple reaction monitoring(MRM)mode.Matrix-matched calibration was recommended to combat the matrix effect.A good linearity was observed in the range of 10−500 ng/mL with correlation coefficients≥0.9950.The mean recoveries for most of the pesticides were in the range of 70%−120%with RSD<20%.The limits of detection ranged 0.28–2.00μg/kg,while the limits of quantification were 0.94–6.65μg/kg.Following the application of“top-down”approach,the expanded measurement uncertainty for all the analytes was<30%.The proposed method was successfully applied to determine pesticide residues in 20 market samples in China,where 9 pesticides were detected and quintozene exceeded the criteria domestically and abroad.展开更多
A new method for screening and identification 420 pesticide residues in fruits and vegetables by ultra-performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry(UPLC-Q-TOF/MS)were deve...A new method for screening and identification 420 pesticide residues in fruits and vegetables by ultra-performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry(UPLC-Q-TOF/MS)were developed.The samples were extracted with acetonitrile/acetic acid(99:1,V/V),and clean-up by SinChERS-Nano(single-step,cheap,effective,rugged,safe,nano)column,determined by UPLC-Q-TOF/MS.The accurate mass database and MS/MS database which contains 420 pesticides were established,the automatic retrieval of detection results was carried on according to the accurate mass,retention time,isotope ratio,ion fragment information,and so on.Method verification was performed on leeks samples.The results showed that 420 pesticides had good linearity in the range of 0.1-100μg/L,and the correlation coeffificients(R2)was greater than 0.990.The limits of detections(LODs)and limits of quantifications(LOQs)of 420 pesticides were in range of 0.05-2.0 and 0.1-5.0μg/L,respectively.The average spike recoveries at 3 levels were 70.1%to 119.7%,and the relative standard deviations(RSD)were lower than 20%(n=6).With this method,a survey of pesticide residues was conducted for 110 samples of 10 different fruits and vegetables,which provided scientific data for ensuring pesticide residue safety of the fruits and vegetables consumed daily by the public.This method was simple,sensitive and accurate,and could be used for rapid screening of 420 pesticide residues in fruits and vegetables.展开更多
In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purificatio...In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purification.After modified quick,easy,cheap,effective,rugged,and safe(QuEChERS)extraction,extracts were directly injected to the TLX(TurboFlow Liquid Xcalibur)system and brought to TurboFlow™columns for on-line purification and then transferred to analytical column for further separation and analysis.TurboFlow™columns types,transfer flow rate,and transfer time were optimized.Limits of detection and limits of quantification of the method obtained for 15 pesticide residues were ranged between 0.2–1.0μg/kg and 0.5–2.0μg/kg in Chinese cabbage and cucumber samples.Recoveries of pesticide residues were in range of 75.3%–103.7%.Matrix effects for 15 pesticides were in range of 5.6%–106.6%.The developed method has been successfully used for the determination of 15 pesticide residues in real samples.展开更多
A convenient,cost-effective and fast method using dynamic microwave-assisted extraction and liquid phase microextraction based on the solidification of a floating drop was proposed to analyze organochlorine pesticides...A convenient,cost-effective and fast method using dynamic microwave-assisted extraction and liquid phase microextraction based on the solidification of a floating drop was proposed to analyze organochlorine pesticides in grains including rice,maize and millet.Twelve samples can be processed simultaneously in the method.During the extraction process,10%acetonitrile-water solutions containing 110μL of n-hexadecane were used to extract organochlorine pesticides.Subsequently,1.0 g sodium chloride was placed in the extract,and then centrifuged and cooled.The n-hexadecane drops containing the analytes were solidifi ed and transferred for determination by gas chromatography-electron capture detector without any further filtration or cleaning process.Limits of detection for organochlorine pesticides were 0.97–1.01μg/kg and the RSDs were in the range of 2.6%–8.5%.The developed technology has succeeded in analyzing six real grains samples and the recoveries of the organochlorine pesticides were 72.2%–94.3%.Compared with the published extraction methods,the developed method was used to analyze organochlorine pesticides in grains,being more environmentally friendly,which is suitable for the daily determination of organochlorine pesticides.展开更多
Aptamers as a kind of biological recognition element have shown great potential in monitoring and the rapid quantification of organophosphorus pesticides(OPPs). However, molecules of OPPs are structurally similar and ...Aptamers as a kind of biological recognition element have shown great potential in monitoring and the rapid quantification of organophosphorus pesticides(OPPs). However, molecules of OPPs are structurally similar and original aptamers selected by systematic evolution of ligands by exponential enrichment are usually long-chain bases, which hamper the further application under OPPs-aptamer recognition. The aim of the research was to develop a new strategy to design oligonucleotide sequences for binding OPPs by combination of experimental and molecular modeling methods. 3D models of aptamers binding OPPs were constructed, and binding energy and the most probable binding site for the OPPs were then determined by molecular docking, and the binding sites were further confirmed by the results of 2-AP replaced experiments. Based on the docking results, a new aptamer for detection 4 representative OPPs with only 29 bases was designed by reasonable truncation and mutation of the reported aptamer(named S4-29). The interaction between this new aptamer and OPPs were analyzed by molecular docking, microscale thermophoresis, circular dichroism and fluorometric analysis. The results revealed that the new aptamer exhibit more superior recognition performance to OPPs, which can be promote the monitoring ability of OPPs contaminations in food.展开更多
Objective Pesticides has gain an increasing awareness because of it is becoming a serious environmental problem and come to threaten the health of humanbeing.The effect of five pesticides(zineb,copforce,the mixture of...Objective Pesticides has gain an increasing awareness because of it is becoming a serious environmental problem and come to threaten the health of humanbeing.The effect of five pesticides(zineb,copforce,the mixture of carbendazim and mancozeb,hymexazol)on soil bacteria,fungi,actinomyces,and Five specific enzymes were chosen for investigation(urease,dehydrogenase,invertase,acid phosphates and protease).Methods The enumeration of the soil micro flora was done by the dilution plate method;The enzyme activity was determined by traditional methods.Shannon-Wiener index as well as 16S rRNA-PCR amplification and DGGE fingerprinting was used for detection of shift in microbial community diversity in pesticides contaminated agricultural soil.Results The outcome showed that the microbial diversity was significantly changed after the application of pesticides,the effect of pesticides on microbe had a order from top to bottom:bacteria-actinomyces-fungi.Conclusions Our results indicate that the use of the pesticides hymexazol resulted in an altered soil community structure,in particular for the actinomyces.Invertase was markedly inhibited by hymexazol,zineb,carbendazim and mancozeb and the inhibiting rates were varied between 30.30% and 21.21%;Urease activity was also inhibited significantly by hymexazol,the inhibiting rate was 37.67%;Protease activity was markedly inhibited by zineb and hymexazol,the inhibiting rates were 27.27% and 18.18% respectively;Phosphates activity was inhibited significantly by hymexazol,zineb,carbendazim and mancozeb,the inhibiting rates were range from 22.12%-3.54%;Dehydrogenase activity was not significantly affected by pesticides.Meanwhile,the correlation of all indexes were analyzed,the data suggested that all indexes existed certain correlation.展开更多
Applying the micronucleus technique T.adescanlia paludosa, the mutagenicity of five pesticides, Decis, Sumicid, Cypermethrin, Trichlorphon and Diazinon were tested. The testing results showed that 0.64%, 0.32%, 0.16%,...Applying the micronucleus technique T.adescanlia paludosa, the mutagenicity of five pesticides, Decis, Sumicid, Cypermethrin, Trichlorphon and Diazinon were tested. The testing results showed that 0.64%, 0.32%, 0.16%, 0.08% of Decis, 0.64%, 0.32%, 0. 16%, 0.04% of Trichlorphon and 0.32%, 0.16%, 0.08%, 0.04% of Diazinon all had mutagenicity on Tradescantia paludosa, but Sumicid and Cypermethrin had no such characteristic.展开更多
Background: Malondialdehyde(MDA) is a candidate general marker of oxidative stress(OS). We sought to assess the relation of MDA to Gulf War illness(GWI) and to a variety of exposures.Methods: This is an observational ...Background: Malondialdehyde(MDA) is a candidate general marker of oxidative stress(OS). We sought to assess the relation of MDA to Gulf War illness(GWI) and to a variety of exposures.Methods: This is an observational study involving subjects from Southern California recruited from October 2011 to May 2014. MDA was assessed in 81 participants(41 GWI-cases, 40 controls). General and Gulf-specific exposures were elicited. MDA case–control comparison was restricted to 40 matched pairs. The potential association between MDA and exposures was assessed using regression analyses. Gulf-specific exposures were incorporated into a case-specific model.Results: Plasma MDA was significantly lower in GWI-cases than controls. Composite pesticide and fuel-solvent exposures negatively predicted MDA in the total sample, as well as in the analyses that included either GWI-cases or controls only. Self-reported exposure to organophosphate(OP) nerve gas was a strong predictor for lower MDA level in veterans with GWI.Conclusions: Past pesticide exposures predicted lower MDA in both veterans with GWI and in healthy controls.展开更多
A solid sustained-release energetic material sample,an eruption device and a complete test system were prepared further to analyse the combustion characteristics of solid sustainedrelease energetic materials.The high-...A solid sustained-release energetic material sample,an eruption device and a complete test system were prepared further to analyse the combustion characteristics of solid sustainedrelease energetic materials.The high-temperature heat flux generated by the combustion of the samples from the eruption device was used to penetrate the Q235 target plate.In addition,the meaning and calculation formula of energy density characterising the all-around performance of heat flux were proposed.The numerical simulation of the combustion effect of samples was carried out.According to the data comparison,the numerical simulation results agreed with the experimental results,and the maximum deviation between the two was less than 8.9%.In addition,the structure of the combustion wave and high-temperature jet was proposed and analysed.Based on theoretical analysis,experimental research and numerical simulation,the theoretical burning rate formula of the sample was established.The maximum error between the theoretically calculated mass burning rate and the experimental results was less than 9.8%.Therefore,using the gas-phase steady-state combustion model to study the combustion characteristics of solid sustained-release energetic materials was reasonable.The theoretical burning rate formula also had high accuracy.Therefore,the model could provide scientific and academic guidance for the theoretical research,system design and practical application of solid sustained-release energetic materials in related fields.展开更多
基金supported by Key Research and Development Project of Shandong Province(2021ZDSYS12)National Natural Science Foundation of China(22076086,21777089)+3 种基金Taishan Scholar Program of Shandong Province(ts20190948)Shandong Province Science and Technology Small and Medium Enterprises Innovation Ability Enhancement Project(2023TSGC0689,2023TSGC0055)Natural Science Foundation of Shandong Province(ZR2021MB086,ZR2023QB035)Jinan City University and Institute Innovation Team Project(2021GXRC061,20228045,202333027)。
文摘Organophosphorus pesticides(OPPs)in foods pose a serious threat to human health,motivating the development of novel analytical methods for their rapid detection and quantification.A magnetic covalent organic framework(M-COF)adsorbent for the magnetic solid-phase extraction(MSPE)of OPPs from foods was reported.M-COF was synthesized by the Schiff base condensation reaction of 1,3,5-tris(4-aminophenyl)benzene and 4,4-biphenyldicarboxaldehyde on the surface of amino-functionalized magnetic nanoparticles.Density functional theory(DFT)calculations showed that adsorption of OPPs onto the surface of M-COF involved hydrophobic effects,van der Waals interactions,π-πinteractions,halogen-N bonding,and hydrogen bonding.Combined with gas chromatography-mass spectrometry(GC-MS)technology,the MSPE method features low limits of detection for OPPs(0.002-0.015μg/L),good reproducibility(1.45%-6.14%),wide linear detection range(0.01-1μg/L,R≥0.9935),and satisfactory recoveries(87.3%-110.4%).The method was successfully applied for the trace analysis of OPPs in spiked fruit juices.
文摘The Nano-Micro Letters(2024)16:193,article by Shangguan et al.,entitled“Making the Complicated Simple:A Minimizing Carrier Strategy on Innovative Nanopesticides”(Nano-Micro Lett.https://doi.org/10.1007/s40820-024-01413-5),was published online on 14 May,2024,with errors.The structural formulas and captions of the three acyl chlorides in Fig.3A were wrong.They should be as shown below.
文摘BACKGROUND:Penehyclidine is a newly developed anticholinergic agent.We aimed to investigate the role of penehyclidine in acute organophosphorus pesticide poisoning(OP)patients.METHODS:We searched the Pubmed,Cochrane library,EMBASE,Chinese National Knowledge Infrastructure(CNKI),Chinese Biomedical literature(CBM)and Wanfang databases.Randomized controlled trials(RCTs)recruiting acute OP patients were identifi ed for meta-analysis.Main outcomes included cure rate,mortality rate,time to atropinization,time to 60%normal acetylcholinesterase(AchE)level,rate of intermediate syndrome(IMS)and rate of adverse drug reactions(ADR).RESULTS:Sixteen RCTs involving 1,334 patients were identifi ed.Compared with the atropineor penehyclidine-alone groups,atropine combined with penehyclidine significantly increased the cure rate(penehyclidine+atropine vs.atropine,0.97 vs.0.86,RR 1.13,95%CI[1.07–1.19];penehyclidine+atropine vs.penehyclidine,0.93 vs.0.80,RR 1.08,95%CI[1.01–1.15])and reduced the mortality rate(penehyclidine+atropine vs.atropine,0.015 vs.0.11,RR 0.17,95%CI[0.06–0.49];penehyclidine+atropine vs.penehyclidine,0.13 vs.0.08,RR 0.23,95%CI[0.04–1.28]).Atropine combined with penehyclidine in OP patients also helped reduce the time to atropinization and AchE recovery,the rate of IMS and the rate of ADR.Compared with a single dose of atropine,a single dose of penehyclidine also signifi cantly elevated the cure rate,reduced times to atropinization,AchE recovery,and rate of IMS.CONCLUSION:Atropine combined with penehyclidine benefi ts OP patients by enhancing the cure rate,mortality rate,time to atropinization,AchE recovery,IMS rate,total ADR and duration of hospitalization.Penehyclidine combined with atropine is likely a better initial therapy for OP patients than atropine alone.
基金the National Key Research and Development Plan of China(2017YFC1702500).
文摘This study established a method for the simultaneous determination of 74 pesticide residues in Panax notoginseng by QuEChERS pretreatment method coupled with GC-MS/MS,and carried out pesticide residue analysis on 20 batches of market samples in China.The samples were extracted with acetonitrile,cleaned up with primary secondary amine(PSA)and octadecylsilane(C18)and determined by GC-MS/MS in multiple reaction monitoring(MRM)mode.Matrix-matched calibration was recommended to combat the matrix effect.A good linearity was observed in the range of 10−500 ng/mL with correlation coefficients≥0.9950.The mean recoveries for most of the pesticides were in the range of 70%−120%with RSD<20%.The limits of detection ranged 0.28–2.00μg/kg,while the limits of quantification were 0.94–6.65μg/kg.Following the application of“top-down”approach,the expanded measurement uncertainty for all the analytes was<30%.The proposed method was successfully applied to determine pesticide residues in 20 market samples in China,where 9 pesticides were detected and quintozene exceeded the criteria domestically and abroad.
基金supported by National Key Research and Development Program of China(2018YFC1603400)Special Technical Support Project of State Administration for Market Regulation(2019YJ009).
文摘A new method for screening and identification 420 pesticide residues in fruits and vegetables by ultra-performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry(UPLC-Q-TOF/MS)were developed.The samples were extracted with acetonitrile/acetic acid(99:1,V/V),and clean-up by SinChERS-Nano(single-step,cheap,effective,rugged,safe,nano)column,determined by UPLC-Q-TOF/MS.The accurate mass database and MS/MS database which contains 420 pesticides were established,the automatic retrieval of detection results was carried on according to the accurate mass,retention time,isotope ratio,ion fragment information,and so on.Method verification was performed on leeks samples.The results showed that 420 pesticides had good linearity in the range of 0.1-100μg/L,and the correlation coeffificients(R2)was greater than 0.990.The limits of detections(LODs)and limits of quantifications(LOQs)of 420 pesticides were in range of 0.05-2.0 and 0.1-5.0μg/L,respectively.The average spike recoveries at 3 levels were 70.1%to 119.7%,and the relative standard deviations(RSD)were lower than 20%(n=6).With this method,a survey of pesticide residues was conducted for 110 samples of 10 different fruits and vegetables,which provided scientific data for ensuring pesticide residue safety of the fruits and vegetables consumed daily by the public.This method was simple,sensitive and accurate,and could be used for rapid screening of 420 pesticide residues in fruits and vegetables.
基金National Key Research and Development Program of China(Project No.2018YFC1603400)Science and Technology Program of Hebei Province(Project No.19225503D)Technical Support Project of State Administration for Market Regulation(Project No.2019YJ009).
文摘In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purification.After modified quick,easy,cheap,effective,rugged,and safe(QuEChERS)extraction,extracts were directly injected to the TLX(TurboFlow Liquid Xcalibur)system and brought to TurboFlow™columns for on-line purification and then transferred to analytical column for further separation and analysis.TurboFlow™columns types,transfer flow rate,and transfer time were optimized.Limits of detection and limits of quantification of the method obtained for 15 pesticide residues were ranged between 0.2–1.0μg/kg and 0.5–2.0μg/kg in Chinese cabbage and cucumber samples.Recoveries of pesticide residues were in range of 75.3%–103.7%.Matrix effects for 15 pesticides were in range of 5.6%–106.6%.The developed method has been successfully used for the determination of 15 pesticide residues in real samples.
基金The study was financially supported by the National Science and Technology Support Program of China(Grant No.2013BAD16B08).
文摘A convenient,cost-effective and fast method using dynamic microwave-assisted extraction and liquid phase microextraction based on the solidification of a floating drop was proposed to analyze organochlorine pesticides in grains including rice,maize and millet.Twelve samples can be processed simultaneously in the method.During the extraction process,10%acetonitrile-water solutions containing 110μL of n-hexadecane were used to extract organochlorine pesticides.Subsequently,1.0 g sodium chloride was placed in the extract,and then centrifuged and cooled.The n-hexadecane drops containing the analytes were solidifi ed and transferred for determination by gas chromatography-electron capture detector without any further filtration or cleaning process.Limits of detection for organochlorine pesticides were 0.97–1.01μg/kg and the RSDs were in the range of 2.6%–8.5%.The developed technology has succeeded in analyzing six real grains samples and the recoveries of the organochlorine pesticides were 72.2%–94.3%.Compared with the published extraction methods,the developed method was used to analyze organochlorine pesticides in grains,being more environmentally friendly,which is suitable for the daily determination of organochlorine pesticides.
基金supported by the National Natural Science Foundation of China (31801647)Sichuan Science and Technology Program (2018JY0194,2020YFN0153,2020YFN0151)。
文摘Aptamers as a kind of biological recognition element have shown great potential in monitoring and the rapid quantification of organophosphorus pesticides(OPPs). However, molecules of OPPs are structurally similar and original aptamers selected by systematic evolution of ligands by exponential enrichment are usually long-chain bases, which hamper the further application under OPPs-aptamer recognition. The aim of the research was to develop a new strategy to design oligonucleotide sequences for binding OPPs by combination of experimental and molecular modeling methods. 3D models of aptamers binding OPPs were constructed, and binding energy and the most probable binding site for the OPPs were then determined by molecular docking, and the binding sites were further confirmed by the results of 2-AP replaced experiments. Based on the docking results, a new aptamer for detection 4 representative OPPs with only 29 bases was designed by reasonable truncation and mutation of the reported aptamer(named S4-29). The interaction between this new aptamer and OPPs were analyzed by molecular docking, microscale thermophoresis, circular dichroism and fluorometric analysis. The results revealed that the new aptamer exhibit more superior recognition performance to OPPs, which can be promote the monitoring ability of OPPs contaminations in food.
文摘Objective Pesticides has gain an increasing awareness because of it is becoming a serious environmental problem and come to threaten the health of humanbeing.The effect of five pesticides(zineb,copforce,the mixture of carbendazim and mancozeb,hymexazol)on soil bacteria,fungi,actinomyces,and Five specific enzymes were chosen for investigation(urease,dehydrogenase,invertase,acid phosphates and protease).Methods The enumeration of the soil micro flora was done by the dilution plate method;The enzyme activity was determined by traditional methods.Shannon-Wiener index as well as 16S rRNA-PCR amplification and DGGE fingerprinting was used for detection of shift in microbial community diversity in pesticides contaminated agricultural soil.Results The outcome showed that the microbial diversity was significantly changed after the application of pesticides,the effect of pesticides on microbe had a order from top to bottom:bacteria-actinomyces-fungi.Conclusions Our results indicate that the use of the pesticides hymexazol resulted in an altered soil community structure,in particular for the actinomyces.Invertase was markedly inhibited by hymexazol,zineb,carbendazim and mancozeb and the inhibiting rates were varied between 30.30% and 21.21%;Urease activity was also inhibited significantly by hymexazol,the inhibiting rate was 37.67%;Protease activity was markedly inhibited by zineb and hymexazol,the inhibiting rates were 27.27% and 18.18% respectively;Phosphates activity was inhibited significantly by hymexazol,zineb,carbendazim and mancozeb,the inhibiting rates were range from 22.12%-3.54%;Dehydrogenase activity was not significantly affected by pesticides.Meanwhile,the correlation of all indexes were analyzed,the data suggested that all indexes existed certain correlation.
文摘Applying the micronucleus technique T.adescanlia paludosa, the mutagenicity of five pesticides, Decis, Sumicid, Cypermethrin, Trichlorphon and Diazinon were tested. The testing results showed that 0.64%, 0.32%, 0.16%, 0.08% of Decis, 0.64%, 0.32%, 0. 16%, 0.04% of Trichlorphon and 0.32%, 0.16%, 0.08%, 0.04% of Diazinon all had mutagenicity on Tradescantia paludosa, but Sumicid and Cypermethrin had no such characteristic.
基金funded by the Depar tment of Defense Congressionally Directed Medical Research Program (GW093063)。
文摘Background: Malondialdehyde(MDA) is a candidate general marker of oxidative stress(OS). We sought to assess the relation of MDA to Gulf War illness(GWI) and to a variety of exposures.Methods: This is an observational study involving subjects from Southern California recruited from October 2011 to May 2014. MDA was assessed in 81 participants(41 GWI-cases, 40 controls). General and Gulf-specific exposures were elicited. MDA case–control comparison was restricted to 40 matched pairs. The potential association between MDA and exposures was assessed using regression analyses. Gulf-specific exposures were incorporated into a case-specific model.Results: Plasma MDA was significantly lower in GWI-cases than controls. Composite pesticide and fuel-solvent exposures negatively predicted MDA in the total sample, as well as in the analyses that included either GWI-cases or controls only. Self-reported exposure to organophosphate(OP) nerve gas was a strong predictor for lower MDA level in veterans with GWI.Conclusions: Past pesticide exposures predicted lower MDA in both veterans with GWI and in healthy controls.
文摘A solid sustained-release energetic material sample,an eruption device and a complete test system were prepared further to analyse the combustion characteristics of solid sustainedrelease energetic materials.The high-temperature heat flux generated by the combustion of the samples from the eruption device was used to penetrate the Q235 target plate.In addition,the meaning and calculation formula of energy density characterising the all-around performance of heat flux were proposed.The numerical simulation of the combustion effect of samples was carried out.According to the data comparison,the numerical simulation results agreed with the experimental results,and the maximum deviation between the two was less than 8.9%.In addition,the structure of the combustion wave and high-temperature jet was proposed and analysed.Based on theoretical analysis,experimental research and numerical simulation,the theoretical burning rate formula of the sample was established.The maximum error between the theoretically calculated mass burning rate and the experimental results was less than 9.8%.Therefore,using the gas-phase steady-state combustion model to study the combustion characteristics of solid sustained-release energetic materials was reasonable.The theoretical burning rate formula also had high accuracy.Therefore,the model could provide scientific and academic guidance for the theoretical research,system design and practical application of solid sustained-release energetic materials in related fields.
