Ecological stoichiometry provides the possibility for linking microbial dynamics with soil carbon(C),nitrogen(N),and phosphorus(P)metabolisms in response to agricultural nutrient management.To determine the roles of f...Ecological stoichiometry provides the possibility for linking microbial dynamics with soil carbon(C),nitrogen(N),and phosphorus(P)metabolisms in response to agricultural nutrient management.To determine the roles of fertilization and residue return with respect to ecological stoichiometry,we collected soil samples from a 30-year field experiment on residue return(maize straw)at rates of 0,2.5,and 5.0 Mg ha^-1 in combination with 8 fertilization treatments:no fertilizer(F0),N fertilizer,P fertilizer,potassium(K)fertilizer,N and P(NP)fertilizers,N and K(NK)fertilizers,P and K(PK)fertilizers,and N,P,and K(NPK)fertilizers.We measured soil organic C(SOC),total N and P,microbial biomass C,N,and P,water-soluble organic C and N,KMnO4-oxidizabIe C(KMnO4-C),and carbon management index(CMI).Compared with the control(F0 treatment without residue return),fertilization and residue return significantly increased the KMn〇4-C content and CMI.Furthermore,compared with the control,residue return significantly increased the SOC content.Moreover,the NPK treatment with residue return at 5.0 Mg ha^-1 significantly enhanced the C:N,C:P,and N:P ratios in the soil,whereas it significantly decreased the C:N and C:P ratios in soil microbial biomass.Therefore,NPK fertilizer application combined with residue return at 5.0 Mg ha^-1 could enhance the SOC content through the stoichiometric plasticity of microorganisms.Residue return and fertilization increased the soil C pools by directly modifying the microbial stoichiometry of the biomass that was C limited.展开更多
Nb doped MnCe0.2Ox complex oxides catalysts prepared via a homogeneous precipitation method were investigated for synergistic catalytic removal of NOx and chlorobenzene(CB)at low temperatures.The MnNb0.4Ce0.2Ox cataly...Nb doped MnCe0.2Ox complex oxides catalysts prepared via a homogeneous precipitation method were investigated for synergistic catalytic removal of NOx and chlorobenzene(CB)at low temperatures.The MnNb0.4Ce0.2Ox catalyst with a molar ratio of Nb/Mn=0.4 exhibits excellent activity and the NOx and CB removal efficiency reaches 94.5%and 96%at 220℃,respectively.Furthermore,the NOx and CB removal efficiency of MnNb0.4Ce0.2Ox still remains above 80%after injecting 300 ppm SO2 and 7 vol%H2 O for 36 h.In addition,the presence of CB and NOx+NH3 can improve the NOx and CB removal efficiency of MnNb0.4Ce0.2Ox,respectively.The analysis results from N2-BET,Py-IR,H2-TPR and NH3-TPD reveal that the introduction of Nb increases the average pore size,pore volume and surface area,promoted the growth of Lewis acid amount obviously,and enhances redox ability of MnCe0.2Ox at 100-250℃.Moreover,the molecular migration process of NOx,NH3,CB and SO2 in NH3-SCR and CB oxidation reaction over MnNb0.4Ce0.2Ox catalysts were systematically studied.In situ DRIFTS,FT-IR and XPS also confirm that the adsorption of sulfate species and SO2 on the surface of MnNb0.4Ce0.2Ox is inhibited effectively by the introduction of Nb in the presence of SO2 and H2 O.Moreover,Nb additives also enhance the structural stability of MnNb0.4Ce0.2Ox,due to the interactions among Mn,Nb and Ce.The NH3-TPD,H2-TPR and in situ DRIFTS results also confirm that the MnNb0.4Ce0.2Ox still retains abundant acid sites and high redox ability in the presence of SO2 and H2O.In summary,MnNb0.4Ce0.2Ox catalysts represent a promising and effective candidate for controlling NOx and CB at low temperatures.展开更多
Roller ends forced-contact and overmuch roll consumption are the widespread problems in temper rolling process of thin strip for two-stand UCM temper mill. Fully thinking the equipment and technology characteristics o...Roller ends forced-contact and overmuch roll consumption are the widespread problems in temper rolling process of thin strip for two-stand UCM temper mill. Fully thinking the equipment and technology characteristics of UCM temper mill, we took the newly-built 1220 UCM temper mill of Baosteel as the research object in this paper. A model of roller ends forced-contact and a calculation model of flatness for UCM temper mill are established after a great deal of site tracing and theoretical researches. On this basis, an optimal mathematical model of roll shape which is suited for UCM temper mill is developed. Working roll curve is the combination of cosine curve and high order curve. The cosine subentry is used to control edge wave, the high order curve subentry is used to control roller ends forced-contact. Furthermore, the chamfering curve of middle roller end is optimized. Those are the innovations. Through the above-mentioned technology, pressure distribution between rollers caused by the shift of middle roll becomes more homogeneous, pressure peak disappeared, working life of roll is improved effectively as well. Relevant technologies have been used to the practice of 1220 UCM temper mill of Baosteel and have achieved good use effects, which is of further extending application value.展开更多
Background The disease burden of tuberculosis(TB)was heavy in Hainan Province,China,and the information on transmission patterns was limited with few studies.This atudy aims to further explore the epidemiological char...Background The disease burden of tuberculosis(TB)was heavy in Hainan Province,China,and the information on transmission patterns was limited with few studies.This atudy aims to further explore the epidemiological charac-teristics and influencing factors of TB in Hainan Province,and thereby contribute valuable scientific evidences for TB elimination in Hainan Province.Methods The TB notification data in Hainan Province from 2013 to 2022 were collected from the Chinese National Disease Control Information System Tuberculosis Surveillance System,along with socio-economic data.The spatial-temporal and population distributions were analyzed,and spatial autocorrelation analysis was conducted to explore TB notification rate clustering.In addition,the epidemiological characteristics of the cases among in-country migrants were described,and the delay pattern in seeking medical care was investigated.Finally,a geographically and tem-porally weighted regression(GTWR)model was adopted to analyze the relationship between TB notification rate and socio-economic indicators.The tailored control suggestions in different regions for TB elimination was provided by understanding epidemiological characteristics and risk factors obtained by GTWR.Results From 2013 to 2022,64,042 cases of TB were notified in Hainan Province.The estimated annual percent-age change of TB notification rate in Hainan Province from 2013 to 2020 was-6.88%[95%confidence interval(CI):-5.30%,-3.69%],with higher rates in central and southern regions.The majority of patients were males(76.33%)and farmers(67.80%).Cases among in-country migrants primarily originated from Sichuan(369 cases),Heilongjiang(267 cases),Hunan(236 cases),Guangdong(174 cases),and Guangxi(139 cases),accounting for 53%.The majority(98.83%)of TB cases were notified through passive case finding approaches,with delay in seeking care.The GTWR analysis showed that gross domestic product per capita,the number of medical institutions and health personnel per 10,oo0 people were main factors affecting the high TB notification rates in some regions in Hainan Province.Dif-ferent regional tailored measures such as more TB specialized hospitals were proposed based on the characteristics of each region.Conclusions The notification rate of TB in Hainan Province has been declining overall but still remained high in central and southern regions.Particular attention should be paid to the prevalence of TB among males,farmers,and outof-province migrant populations.The notification rate was also influenced by economic development and medical conditions,indicating the need of more TB specialized hospitals,active surveillance and other tailored prevention and control measures to promote the progress of TB elimination in Hainan Province.展开更多
A gold nanoparticle(AuNP)aggregation-induced colorimetric aptasensing method for quantitative detection of sulfadimethoxine(SDM)with a smartphone was developed.AuNPs were complexed with aptamers which protected Au NPs...A gold nanoparticle(AuNP)aggregation-induced colorimetric aptasensing method for quantitative detection of sulfadimethoxine(SDM)with a smartphone was developed.AuNPs were complexed with aptamers which protected Au NPs from aggregating in high-concentration salt solutions.In the presence of SDM,SDM bound with the aptamer on the surface of Au NPs with higher affinity,which competitively desorbed the aptamer from the AuNP surface and resulted in AuNPs aggregation,accompanied with a color change from red to purple-blue.The R,G and B values of images taken by a smartphone camera were analyzed with an app on the smartphone,and were utilized for quantitative analysis of SDM.Under the optimized conditions,the colorimetric aptasensing method using a smartphone showed high sensitivity for SDM,with the limit of detection of 0.023 ppm,lower than the allowed maximum SDM residue limit.This study provides a simple,fast,and easy to read method for on-site quantitative biochemical and cellular analysis.展开更多
Established on the Intel Multi-Core Embedded platform, using 802.11 Wireless Network protocols as the communication medium, combining with Radio Frequency-Communication and Ultrasonic Ranging, imple-ment a mobile term...Established on the Intel Multi-Core Embedded platform, using 802.11 Wireless Network protocols as the communication medium, combining with Radio Frequency-Communication and Ultrasonic Ranging, imple-ment a mobile terminal system in an intellectualized building. It can provide its holder such functions: 1) Accurate Positioning 2) Intelligent Navigation 3) Video Monitoring 4) Wireless Communication. The inno-vative point for this paper is to apply the multi-core computing on the embedded system to promote its com-puting speed and give a real-time performance and apply this system into the indoor environment for the purpose of emergent event or rescuing.展开更多
Roller ends forced-contact and overmuch roll consumption are the widespread problems in temper rolling process of thin strip for two-stand UCM temper mill. Fully thinking the equipment and technology characteristics o...Roller ends forced-contact and overmuch roll consumption are the widespread problems in temper rolling process of thin strip for two-stand UCM temper mill. Fully thinking the equipment and technology characteristics of UCM temper mill, we took the newly-built 1220 UCM temper mill of Baosteel as the research object in this paper. A model of roller ends forced-contact and a calculation model of flatness for UCM temper mill are established after a great deal of site tracing and theoretical researches. On this basis, an optimal mathematical model of roll shape which is suited for UCM temper mill is developed. Working roll curve is the combination of cosine curve and high order curve. The cosine subentry is used to control edge wave, the high order curve subentry is used to control roller ends forced-contact. Furthermore, the chamfering curve of middle roller end is optimized. Those are the innovations. Through the above-mentioned technology, pressure distribution between rollers caused by the shift of middle roll becomes more homogeneous, pressure peak disappeared, working life of roll is improved effectively as well. Relevant technologies have been used to the practice of 1220 UCM temper mill of Baosteel and have achieved good use effects, which is of further extending application value [1].展开更多
Novel strategies for the simultaneous and portable detection of multiple analytes are highly favorable for clinical diagnosis and healthcare.Conventional colorimetric enzyme-linked immunosorbent assay(ELISA)is a widel...Novel strategies for the simultaneous and portable detection of multiple analytes are highly favorable for clinical diagnosis and healthcare.Conventional colorimetric enzyme-linked immunosorbent assay(ELISA)is a widely used laboratory technique for medical diagnostics,quality control,and research applications.However,nonspecific absorption of proteins may lead to a reduction of functional sites,resulting in high background and low sensitivity in ELISA.Herein,we report a simple method of functionalization of poly(methyl methacrylate)(PMMA)with polylysine to be used as the microfluidic microplate substrate for enhanced ELISA,enabling rapid,ultrasensitive,and multiplexed detection of infectious diseases.FTIR and fluorescence microscopy characterization confirmed high amine densities on polylysine-modified PMMA surface,resulting in high detection sensitivity of the colorimetric ELISA on the PMMA microdevice.The ultrasensitive polylysine-modified microplate can immobilize protein within 20 min and results of the assay can be viewed by the naked eye or scanned through a simple desktop scanner for quantitative analysis within 90 min.A sandwich-type immunoassay for the rapid and sensitive detection of immunoglobulin G(IgG),hepatitis B surface antigen(HBsAg),and hepatitis B core antigen(HBcAg)was demonstrated as a proof-of-concept for multiplexed detection.The limits of detection(LOD)of 200.0 pg/mL for IgG,180.0 pg/mL for HBsAg,and 300.0 pg/mL for HBcAg were achieved,without any specialized equipment like a microplate reader.The surface-modified microchip exhibited about 10-fold higher sensitivity than traditional microplates.This surface-modified microplate has tremendous potential as a point-ofcare multiplexed testing platform for many applications ranging from clinical diagnosis to environmental monitoring,particularly in resource-limited settings.展开更多
Conventional colorimetric enzyme-linked immunosorbent assay(ELISA)is a time-consuming laboratory assay that is not very sensitive and consumes a large amount of samples.Herein,the development of a reusable,cost-effect...Conventional colorimetric enzyme-linked immunosorbent assay(ELISA)is a time-consuming laboratory assay that is not very sensitive and consumes a large amount of samples.Herein,the development of a reusable,cost-effective,and eco-friendly poly(methyl methacrylate)(PMMA)/paper hybrid plug-and-play(PnP)device for high-sensitivity immunoassay by analyte enrichment and efficient passing-through washing has been reported.The PMMA device has multiple slots where a pre-patterned paper substrate can be inserted.The sample flows back-and-forth through a low-cost,3D paper substrate within the PMMA channels,thereby enhancing the amount of analyte adsorbed and dramatically increasing the sensitivity while decreasing the assay time.After the enrichment assay,the paper substrate can simply be pulled out of the device,and the results can be qualitatively viewed with the naked eye or scanned through a simple desktop scanner for quantitative analysis.The paper substrate can be replaced with a new substrate so that the device can be reused.The limits of detection(LODs)of 200pg/mL for immunoglobulin G(IgG)and 270 pg/mL for hepatitis B surface antigen(HBsAg)were obtained.This IgG assay is at least 10 times more sensitive than commercial ELISA kits.In addition,the PnP ELISA exhibited a significant increase in the linear dynamic range from 3 orders of magnitude in a common paper-based device to a wide range of six orders of magnitude in the PnP hybrid device.This reusable PnP device has great potential for the low-cost yet high-sensitivity detection of infectious diseases,cancers,and other important biomolecules.展开更多
Aims Soil CO_(2) emission from steppes is affected by soil properties and vegetation in different successional stages.Primary and secondary succession of plants frequently occurred at the meadow steppe in Songnen Plai...Aims Soil CO_(2) emission from steppes is affected by soil properties and vegetation in different successional stages.Primary and secondary succession of plants frequently occurred at the meadow steppe in Songnen Plain,Northeast China,which indicates the large uncer-tainty associated with CO_(2) emission in this environment.This study aims to investigate the temporal variations of soil respiration(Rs)and the effect of plant succession on cumulative soil CO_(2) emission during the growing season.Methods Using a LI-6400 soil CO_(2) flux system,Rs of five vegetation types which represented different stages of plant succession in meadow steppes of Songnen Plain,China,was investigated during the grow-ing seasons of 2011 and 2012.Important Findings Soil temperature(Ts)was the dominant controlling factor of Rs,which could explain~64%of the change in CO_(2) fluxes.The Q10 values of Rs were ranged from 2.0 to 6.7,showing a decreasing trend with the plant successional stages.The cumulative CO_(2) emis-sion increased with the degree of vegetation succession and it aver-aged to 316±6 g C m^(−2)(ranges:74.8±6.7 to 516.5±11.4 g C m^(−2))during the growing season.The magnitude of soil CO_(2) emission during the growing season was positively correlated with above-ground plant biomass,soil organic carbon content and mean soil water content,while negatively linked to mean Ts,pH,electrical conductivity and exchangeable sodium percentages.The results implied that soil CO_(2) emission increased with the development of plant communities toward more advanced stages.Our findings pro-vided valuable information for understanding the variations of CO_(2) emission in the process of vegetation succession.展开更多
Background:A relevant questionnaire that evaluates disease awareness of patients with re-mitted schizophrenia is lacking in China.Objective:The purpose of the current study was to develop a questionnaire suitable for ...Background:A relevant questionnaire that evaluates disease awareness of patients with re-mitted schizophrenia is lacking in China.Objective:The purpose of the current study was to develop a questionnaire suitable for eval-uating the disease knowledge-attitude-practice awareness on the part of patients with remitted schizophrenia,thus providing a reliable tool for evaluating patient knowledge of the disease and self-management ability.Methods:To establish a theoretical framework,the literature was reviewed,experts were con-sulted,a semi-structured interview was conducted,and a questionnaire survey was administered to prepare a questionnaire for disease knowledge-attitude-practice awareness on the part of patients with remitted schizophrenia.Results:Exploratory factor analysis showed that the questionnaire consists of four dimen-sions:etiology awareness;risk factor awareness;treatment awareness;and rehabilitation aware-ness.The four dimensions account for 56.6%of the total variability.Confirmatory factor anal-ysis showed that the fitting indices for the structural equation model are as follows:df=1.187;GFI=0.877;AGFI=0.856;and RMSEA=0.030.The total Cronbach a factor for the questionnaire was 0.878.The Cronbach a for each dimension was 0.59-0.81.Conclusion:The questionnaire for disease knowledge-attitude-practice awareness on the part of patients with remitted schizophrenia has better reliability and validity.展开更多
基金This research was financially supported by the Special Foundation for State Major Basic Research Program of China(No.2016YFC0501202)the Special Foundation for Basic Research Program in Soil of Chinese Academy Sciences(Nos.XDB 15030103 and XDA23070501)+2 种基金the National Natural Science Foundation of China(Nos.41920104008 and 41701332)the Key Laboratory Foundation of Mollisols Agroecology(No.2016ZKHT-05)the 135 Project of Northeast Institute of Geography and Agroecology of Chinese Academy Sciences(No.Y6H2043001).
文摘Ecological stoichiometry provides the possibility for linking microbial dynamics with soil carbon(C),nitrogen(N),and phosphorus(P)metabolisms in response to agricultural nutrient management.To determine the roles of fertilization and residue return with respect to ecological stoichiometry,we collected soil samples from a 30-year field experiment on residue return(maize straw)at rates of 0,2.5,and 5.0 Mg ha^-1 in combination with 8 fertilization treatments:no fertilizer(F0),N fertilizer,P fertilizer,potassium(K)fertilizer,N and P(NP)fertilizers,N and K(NK)fertilizers,P and K(PK)fertilizers,and N,P,and K(NPK)fertilizers.We measured soil organic C(SOC),total N and P,microbial biomass C,N,and P,water-soluble organic C and N,KMnO4-oxidizabIe C(KMnO4-C),and carbon management index(CMI).Compared with the control(F0 treatment without residue return),fertilization and residue return significantly increased the KMn〇4-C content and CMI.Furthermore,compared with the control,residue return significantly increased the SOC content.Moreover,the NPK treatment with residue return at 5.0 Mg ha^-1 significantly enhanced the C:N,C:P,and N:P ratios in the soil,whereas it significantly decreased the C:N and C:P ratios in soil microbial biomass.Therefore,NPK fertilizer application combined with residue return at 5.0 Mg ha^-1 could enhance the SOC content through the stoichiometric plasticity of microorganisms.Residue return and fertilization increased the soil C pools by directly modifying the microbial stoichiometry of the biomass that was C limited.
基金Project supported by the National Natural Science Foundation of China(51902166)the Natural Science Foundation of Jiangsu Province(BK20190786+6 种基金BK20170954)the Key Research and Development Program of Jiangsu Province(BE2018074)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(18KJB430019)the Startup Foundation for Introducing Talent of NUIST(2017r073)the USA NIH/NIAID(R21AI107415)the NSF-PREM program(DMR 1827745)the Philadelphia Foundation。
文摘Nb doped MnCe0.2Ox complex oxides catalysts prepared via a homogeneous precipitation method were investigated for synergistic catalytic removal of NOx and chlorobenzene(CB)at low temperatures.The MnNb0.4Ce0.2Ox catalyst with a molar ratio of Nb/Mn=0.4 exhibits excellent activity and the NOx and CB removal efficiency reaches 94.5%and 96%at 220℃,respectively.Furthermore,the NOx and CB removal efficiency of MnNb0.4Ce0.2Ox still remains above 80%after injecting 300 ppm SO2 and 7 vol%H2 O for 36 h.In addition,the presence of CB and NOx+NH3 can improve the NOx and CB removal efficiency of MnNb0.4Ce0.2Ox,respectively.The analysis results from N2-BET,Py-IR,H2-TPR and NH3-TPD reveal that the introduction of Nb increases the average pore size,pore volume and surface area,promoted the growth of Lewis acid amount obviously,and enhances redox ability of MnCe0.2Ox at 100-250℃.Moreover,the molecular migration process of NOx,NH3,CB and SO2 in NH3-SCR and CB oxidation reaction over MnNb0.4Ce0.2Ox catalysts were systematically studied.In situ DRIFTS,FT-IR and XPS also confirm that the adsorption of sulfate species and SO2 on the surface of MnNb0.4Ce0.2Ox is inhibited effectively by the introduction of Nb in the presence of SO2 and H2 O.Moreover,Nb additives also enhance the structural stability of MnNb0.4Ce0.2Ox,due to the interactions among Mn,Nb and Ce.The NH3-TPD,H2-TPR and in situ DRIFTS results also confirm that the MnNb0.4Ce0.2Ox still retains abundant acid sites and high redox ability in the presence of SO2 and H2O.In summary,MnNb0.4Ce0.2Ox catalysts represent a promising and effective candidate for controlling NOx and CB at low temperatures.
文摘Roller ends forced-contact and overmuch roll consumption are the widespread problems in temper rolling process of thin strip for two-stand UCM temper mill. Fully thinking the equipment and technology characteristics of UCM temper mill, we took the newly-built 1220 UCM temper mill of Baosteel as the research object in this paper. A model of roller ends forced-contact and a calculation model of flatness for UCM temper mill are established after a great deal of site tracing and theoretical researches. On this basis, an optimal mathematical model of roll shape which is suited for UCM temper mill is developed. Working roll curve is the combination of cosine curve and high order curve. The cosine subentry is used to control edge wave, the high order curve subentry is used to control roller ends forced-contact. Furthermore, the chamfering curve of middle roller end is optimized. Those are the innovations. Through the above-mentioned technology, pressure distribution between rollers caused by the shift of middle roll becomes more homogeneous, pressure peak disappeared, working life of roll is improved effectively as well. Relevant technologies have been used to the practice of 1220 UCM temper mill of Baosteel and have achieved good use effects, which is of further extending application value.
文摘Background The disease burden of tuberculosis(TB)was heavy in Hainan Province,China,and the information on transmission patterns was limited with few studies.This atudy aims to further explore the epidemiological charac-teristics and influencing factors of TB in Hainan Province,and thereby contribute valuable scientific evidences for TB elimination in Hainan Province.Methods The TB notification data in Hainan Province from 2013 to 2022 were collected from the Chinese National Disease Control Information System Tuberculosis Surveillance System,along with socio-economic data.The spatial-temporal and population distributions were analyzed,and spatial autocorrelation analysis was conducted to explore TB notification rate clustering.In addition,the epidemiological characteristics of the cases among in-country migrants were described,and the delay pattern in seeking medical care was investigated.Finally,a geographically and tem-porally weighted regression(GTWR)model was adopted to analyze the relationship between TB notification rate and socio-economic indicators.The tailored control suggestions in different regions for TB elimination was provided by understanding epidemiological characteristics and risk factors obtained by GTWR.Results From 2013 to 2022,64,042 cases of TB were notified in Hainan Province.The estimated annual percent-age change of TB notification rate in Hainan Province from 2013 to 2020 was-6.88%[95%confidence interval(CI):-5.30%,-3.69%],with higher rates in central and southern regions.The majority of patients were males(76.33%)and farmers(67.80%).Cases among in-country migrants primarily originated from Sichuan(369 cases),Heilongjiang(267 cases),Hunan(236 cases),Guangdong(174 cases),and Guangxi(139 cases),accounting for 53%.The majority(98.83%)of TB cases were notified through passive case finding approaches,with delay in seeking care.The GTWR analysis showed that gross domestic product per capita,the number of medical institutions and health personnel per 10,oo0 people were main factors affecting the high TB notification rates in some regions in Hainan Province.Dif-ferent regional tailored measures such as more TB specialized hospitals were proposed based on the characteristics of each region.Conclusions The notification rate of TB in Hainan Province has been declining overall but still remained high in central and southern regions.Particular attention should be paid to the prevalence of TB among males,farmers,and outof-province migrant populations.The notification rate was also influenced by economic development and medical conditions,indicating the need of more TB specialized hospitals,active surveillance and other tailored prevention and control measures to promote the progress of TB elimination in Hainan Province.
基金the National Natural Science Foundation of China(Nos.21874098 and 61775157)Program for the Outstanding Innovative Teams of Higher Learning Institutions of Shanxi,Key R&D plan of Shanxi Province(International cooperation)(No.201903D421053)+3 种基金Key R&D Plan of Shanxi Province(high technologies field,No.201903D121158)the U.S.NSF(Nos.IIP2122712 and IIP 2052347)CPRIT(No.RP210165)DOT(No.CARTEEH)。
文摘A gold nanoparticle(AuNP)aggregation-induced colorimetric aptasensing method for quantitative detection of sulfadimethoxine(SDM)with a smartphone was developed.AuNPs were complexed with aptamers which protected Au NPs from aggregating in high-concentration salt solutions.In the presence of SDM,SDM bound with the aptamer on the surface of Au NPs with higher affinity,which competitively desorbed the aptamer from the AuNP surface and resulted in AuNPs aggregation,accompanied with a color change from red to purple-blue.The R,G and B values of images taken by a smartphone camera were analyzed with an app on the smartphone,and were utilized for quantitative analysis of SDM.Under the optimized conditions,the colorimetric aptasensing method using a smartphone showed high sensitivity for SDM,with the limit of detection of 0.023 ppm,lower than the allowed maximum SDM residue limit.This study provides a simple,fast,and easy to read method for on-site quantitative biochemical and cellular analysis.
文摘Established on the Intel Multi-Core Embedded platform, using 802.11 Wireless Network protocols as the communication medium, combining with Radio Frequency-Communication and Ultrasonic Ranging, imple-ment a mobile terminal system in an intellectualized building. It can provide its holder such functions: 1) Accurate Positioning 2) Intelligent Navigation 3) Video Monitoring 4) Wireless Communication. The inno-vative point for this paper is to apply the multi-core computing on the embedded system to promote its com-puting speed and give a real-time performance and apply this system into the indoor environment for the purpose of emergent event or rescuing.
文摘Roller ends forced-contact and overmuch roll consumption are the widespread problems in temper rolling process of thin strip for two-stand UCM temper mill. Fully thinking the equipment and technology characteristics of UCM temper mill, we took the newly-built 1220 UCM temper mill of Baosteel as the research object in this paper. A model of roller ends forced-contact and a calculation model of flatness for UCM temper mill are established after a great deal of site tracing and theoretical researches. On this basis, an optimal mathematical model of roll shape which is suited for UCM temper mill is developed. Working roll curve is the combination of cosine curve and high order curve. The cosine subentry is used to control edge wave, the high order curve subentry is used to control roller ends forced-contact. Furthermore, the chamfering curve of middle roller end is optimized. Those are the innovations. Through the above-mentioned technology, pressure distribution between rollers caused by the shift of middle roll becomes more homogeneous, pressure peak disappeared, working life of roll is improved effectively as well. Relevant technologies have been used to the practice of 1220 UCM temper mill of Baosteel and have achieved good use effects, which is of further extending application value [1].
基金support from NIH/NIAID(R41AI162477)the U.S.NSF(IIP2122712 and CHE2216473)+7 种基金the Cancer Prevention and Research Institute of Texas(CPRIT,RP210165)the TTUHSC-UTEP Joint Seed Grant,and the AAFS Foundation Research Lucas grantthe prior financial support to our research from the NIH/NIAID(R21AI107415)the NIH/NIGMS(SC2GM105584)the NIH/NIMHD RCMI Pilot grant(5G12MD007593-22)the NIH Building Scholar Summer Sabbatical Award,the NSF(IIP1953841,IIP2052347,and DMR1827745)the DOT(CARTEEH)the Philadelphia Foundation,the Medical Center of the Americas Foundation(MCA)。
文摘Novel strategies for the simultaneous and portable detection of multiple analytes are highly favorable for clinical diagnosis and healthcare.Conventional colorimetric enzyme-linked immunosorbent assay(ELISA)is a widely used laboratory technique for medical diagnostics,quality control,and research applications.However,nonspecific absorption of proteins may lead to a reduction of functional sites,resulting in high background and low sensitivity in ELISA.Herein,we report a simple method of functionalization of poly(methyl methacrylate)(PMMA)with polylysine to be used as the microfluidic microplate substrate for enhanced ELISA,enabling rapid,ultrasensitive,and multiplexed detection of infectious diseases.FTIR and fluorescence microscopy characterization confirmed high amine densities on polylysine-modified PMMA surface,resulting in high detection sensitivity of the colorimetric ELISA on the PMMA microdevice.The ultrasensitive polylysine-modified microplate can immobilize protein within 20 min and results of the assay can be viewed by the naked eye or scanned through a simple desktop scanner for quantitative analysis within 90 min.A sandwich-type immunoassay for the rapid and sensitive detection of immunoglobulin G(IgG),hepatitis B surface antigen(HBsAg),and hepatitis B core antigen(HBcAg)was demonstrated as a proof-of-concept for multiplexed detection.The limits of detection(LOD)of 200.0 pg/mL for IgG,180.0 pg/mL for HBsAg,and 300.0 pg/mL for HBcAg were achieved,without any specialized equipment like a microplate reader.The surface-modified microchip exhibited about 10-fold higher sensitivity than traditional microplates.This surface-modified microplate has tremendous potential as a point-ofcare multiplexed testing platform for many applications ranging from clinical diagnosis to environmental monitoring,particularly in resource-limited settings.
基金We would like to acknowledge the financial support from the National Institute of Allergy and Infectious Disease of the NIH(R21AI107415)the U.S.NSF-PREM program(DMR 1827745)+2 种基金the Philadelphia Foundation,and the Medical Center of the Americas Foundation.Financial support from the National Institute of General Medical Sciences of the NIH(SC2GM105584)the NIH RCMI Pilot grant,University of Texas(UT)System for the STARS awardthe University of Texas at El Paso(UTEP)for the IDR Program,Multidisciplinary Research Award Program(MRAP)and URI Program is also greatly acknowledged.
文摘Conventional colorimetric enzyme-linked immunosorbent assay(ELISA)is a time-consuming laboratory assay that is not very sensitive and consumes a large amount of samples.Herein,the development of a reusable,cost-effective,and eco-friendly poly(methyl methacrylate)(PMMA)/paper hybrid plug-and-play(PnP)device for high-sensitivity immunoassay by analyte enrichment and efficient passing-through washing has been reported.The PMMA device has multiple slots where a pre-patterned paper substrate can be inserted.The sample flows back-and-forth through a low-cost,3D paper substrate within the PMMA channels,thereby enhancing the amount of analyte adsorbed and dramatically increasing the sensitivity while decreasing the assay time.After the enrichment assay,the paper substrate can simply be pulled out of the device,and the results can be qualitatively viewed with the naked eye or scanned through a simple desktop scanner for quantitative analysis.The paper substrate can be replaced with a new substrate so that the device can be reused.The limits of detection(LODs)of 200pg/mL for immunoglobulin G(IgG)and 270 pg/mL for hepatitis B surface antigen(HBsAg)were obtained.This IgG assay is at least 10 times more sensitive than commercial ELISA kits.In addition,the PnP ELISA exhibited a significant increase in the linear dynamic range from 3 orders of magnitude in a common paper-based device to a wide range of six orders of magnitude in the PnP hybrid device.This reusable PnP device has great potential for the low-cost yet high-sensitivity detection of infectious diseases,cancers,and other important biomolecules.
基金National Natural Science Foundation of China(31100403,41101207)Special Fund for Agro-scientific Research in the Public Interest,China(201303095-8).
文摘Aims Soil CO_(2) emission from steppes is affected by soil properties and vegetation in different successional stages.Primary and secondary succession of plants frequently occurred at the meadow steppe in Songnen Plain,Northeast China,which indicates the large uncer-tainty associated with CO_(2) emission in this environment.This study aims to investigate the temporal variations of soil respiration(Rs)and the effect of plant succession on cumulative soil CO_(2) emission during the growing season.Methods Using a LI-6400 soil CO_(2) flux system,Rs of five vegetation types which represented different stages of plant succession in meadow steppes of Songnen Plain,China,was investigated during the grow-ing seasons of 2011 and 2012.Important Findings Soil temperature(Ts)was the dominant controlling factor of Rs,which could explain~64%of the change in CO_(2) fluxes.The Q10 values of Rs were ranged from 2.0 to 6.7,showing a decreasing trend with the plant successional stages.The cumulative CO_(2) emis-sion increased with the degree of vegetation succession and it aver-aged to 316±6 g C m^(−2)(ranges:74.8±6.7 to 516.5±11.4 g C m^(−2))during the growing season.The magnitude of soil CO_(2) emission during the growing season was positively correlated with above-ground plant biomass,soil organic carbon content and mean soil water content,while negatively linked to mean Ts,pH,electrical conductivity and exchangeable sodium percentages.The results implied that soil CO_(2) emission increased with the development of plant communities toward more advanced stages.Our findings pro-vided valuable information for understanding the variations of CO_(2) emission in the process of vegetation succession.
基金Supported by the National Natural Science Foundation of China(NSFC 71173065)the Natural Science Foundation of Inner Mongolia Autonomous Region[2013MS1175].
文摘Background:A relevant questionnaire that evaluates disease awareness of patients with re-mitted schizophrenia is lacking in China.Objective:The purpose of the current study was to develop a questionnaire suitable for eval-uating the disease knowledge-attitude-practice awareness on the part of patients with remitted schizophrenia,thus providing a reliable tool for evaluating patient knowledge of the disease and self-management ability.Methods:To establish a theoretical framework,the literature was reviewed,experts were con-sulted,a semi-structured interview was conducted,and a questionnaire survey was administered to prepare a questionnaire for disease knowledge-attitude-practice awareness on the part of patients with remitted schizophrenia.Results:Exploratory factor analysis showed that the questionnaire consists of four dimen-sions:etiology awareness;risk factor awareness;treatment awareness;and rehabilitation aware-ness.The four dimensions account for 56.6%of the total variability.Confirmatory factor anal-ysis showed that the fitting indices for the structural equation model are as follows:df=1.187;GFI=0.877;AGFI=0.856;and RMSEA=0.030.The total Cronbach a factor for the questionnaire was 0.878.The Cronbach a for each dimension was 0.59-0.81.Conclusion:The questionnaire for disease knowledge-attitude-practice awareness on the part of patients with remitted schizophrenia has better reliability and validity.
