Nitrogen(N)priming is a microbially mediated biochemical process as affected by different incorporation practices.However,little information is known about the microbial mechanisms driving the response of N priming to...Nitrogen(N)priming is a microbially mediated biochemical process as affected by different incorporation practices.However,little information is known about the microbial mechanisms driving the response of N priming to co-operation of Chinese milk vetch(CMV,Astragalus sinicus L.)and different rates of chemical fertilizers in paddy soils in South China.Here,an anaerobic incubation experiment was conducted to study N priming effects(PE)and their relationships with soil microbial functional genes after CMV incorporation alone(M),co-incorporation of CMV with 100%(normal dosage)chemical fertilizers(MC100),and co-incorporation of CMV with 80% chemical fertilizers(MC80).Co-incorporation of CMV and chemical fertilizers enhanced the short-time scale(the first 20 d of incubation)positive PE of N,while no significant differences existed among the three treatments on day 60 or 90 of incubation(P>0.05).Compared with the M treatment,gross priming effect(GPE)in the MC100 and MC80 treatments significantly increased by 34.0% and 31.3%,respectively,and net priming effect(NPE)increased by 47.7% and 47.8%,respectively,during the first 20 d of incubation(P<0.05).This was likely attributed to soil nutrient availability and added substrate quality.The MC100 and MC80 treatments increased the gdhA gene abundance by 5.0% and 9.8%,increased the gdh2 gene abundance by 12.7% and 45.7%,and increased the nasB gene abundance by 9.5% and 41.4%,respectively,in comparison with the M treatment on day 20 of incubation.Correlation analyses indicated that soil microbial functional genes involved in N mineralization(gdhA and gdh2),assimilatory nitrate reduction(nasB),and nitrification(amoB)were significantly correlated with N priming under different incorporation practices during the incubation period(P<0.05).Thus,co-incorporation of CMV and chemical fertilizers can regulate soil microbial community functional gene structure,which may accelerate mineralization and assimilatory nitrate reduction and inhibit nitrification,thereby increasing the short-term positive PE of N in the present study.展开更多
BACKGROUND： Dyslexic children exhibit reading ability unmatched to age, although they possess normal intelligence and are well educated. OBJECTIVE： To examine the performance of dyslexic children in Chinese charac...BACKGROUND： Dyslexic children exhibit reading ability unmatched to age, although they possess normal intelligence and are well educated. OBJECTIVE： To examine the performance of dyslexic children in Chinese characters visual recognition tasks and to investigate the relationship between priming effect in character recognition and dyslexia. DESIGN, TIME AND SETTING： A case-control study was performed at the Department of Children and Adolescent Health and Maternal Care, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology between March and June 2007. PARTICIPANTS： A total of 75 primary school students in grades 3 and 5 were selected from two primary schools in Wuhan City, Hubei province, China, and were assigned to three groups. （1） Reading disability （RD, n = 25）; （2） chronological age （CA） group （n = 25 normal readers that were intelligence quotient and age-matched to the RD group）; （3） reading level （RL） group （n = 25 normal readers that were intelligence quotient and RL-matched to the RD group）. All children were right-handed and had normal or corrected-to-normal vision. METHODS： Recognition of target characters was performed in each child using a masked prime paradigm. Recognition speed and accuracy of graphic, phonological, and semantic characters were examined. Simultaneously, data, with respect to response time for each target character and error rate, were recorded to calculate facilitation values （unrelated RT-related RT）. MAIN OUTCOME MEASURES： Response time, facilitation, and error rate in Chinese character recognition task were calculated. RESULTS： The baseline-adjusted facilitation of graphic, phonological, and semantic priming for dyslexic children was -0.010, -0.010, and 0.001, respectively. Dyslexic children displayed inhibition in graphic and phonological prime conditions. Facilitations under the three prime conditions were 0.026, 0.026, and 0.022 for the CA group. In the RL group, results were 0.062, 0.058, and 0.031 respectively. The differences of baseline-adjusted facilitation across the three groups were significant [F （2, 216） = 17.91, P 〈 0.01 ], whereas the main effect of prime condition IF （2, 216） = 0.49, P 〉 0.05] and the interaction of group x prime condition [F （4, 216） = 0.91, P 〉 0.05] were not significant. The error rate under the three prime conditions was 0.066, 0.077, and 0.079 for the RD group. As for the CA group, the results were 0.057, 0.071, and 0.074 accordingly, and in the RL group, the results were 0.119, 0.111, and 0.121, respectively. The difference of error rate across the three groups was significant （F = 6.61, P = 0.002）. The error rate was significantly greater in the RL group, compared with the CA and RD groups, while no significant difference existed between the RD and CA groups. CONCLUSION： Dyslexic children were slower to recognize target characters than normal readers, and did not exhibit significant prime effects in graphic and phonological primer condition. These results suggested that dyslexic children exhibited general deficits in phonological and graphic processing, and presented a different pattern in character recognition. These results could be interpreted by parallel-distributed processing models.展开更多
In terrestrial ecosystems,deep soils(below 30 cm)are major organic carbon(C)pools.The labile carbon input could alter soil organic carbon(SOC)mineralization,resulting in priming effect(PE),which could be modified by n...In terrestrial ecosystems,deep soils(below 30 cm)are major organic carbon(C)pools.The labile carbon input could alter soil organic carbon(SOC)mineralization,resulting in priming effect(PE),which could be modified by nitrogen(N)availability,however,the underlying mechanism is unclear for deep soils,which complicates the prediction of deep soil C cycling in response to N deposition.A series of N applications with ^(13)C labeled glucose was set to investigate the effect of labile C and N on deep SOC mineralization.Microbial biomass,functional community,metabolic efficiency and enzyme activities were examined for their effects on SOC mineralization and PE.During incubation,glucose addition promoted SOC mineralization,resulting in positive PE.The magnitude of PE decreased significantly with increasing N.The N-regulated PE was not dependent on extracellular enzyme activities but was positively correlated with carbon use efficiency and negatively with metabolic quotient.Higher N levels resulted in higher microbial biomass and SOC-derived microbial biomass than lower N levels.These results suggest that the decline in the PE under high N availability was mainly controlled by higher microbial metabolic efficiency which allocated more C for growth.Structural equation modelling also revealed that microbial metabolic efficiency rather than enzyme activities was the main factor regulating the PE.The negative effect of additional N suggests that future N deposition could promote soil C sequestration.展开更多
The priming effect(PE)induced by biochar provides a basis for evaluating its carbon(C)sequestration potential in soils.A 60 days’laboratory incubation was conducted,which involved the amendment of biochar(1%of soil m...The priming effect(PE)induced by biochar provides a basis for evaluating its carbon(C)sequestration potential in soils.A 60 days’laboratory incubation was conducted,which involved the amendment of biochar(1%of soil mass)produced from rice straw at 300℃(B300)and 500℃(B500)to young(Y)and old(O)poplar plantation soils,with the aim of studying the responses of biochar-induced PEs to poplar plantation ages.This incubation included six treatments:Y+CK(control),Y+B300,Y+B500,O+CK,O+B300,and O+B500.Carbon dioxide(CO_(2))emissions were significantly increased(p<0.05)in the B300 amended soils,while it was decreased in the B500 amended soils compared to the CK.The primed CO_(2) emissions were 2.35 times higher in the Y+B300 than the O+B300 treatments,which was measured to be 18.6 and 5.56 mg C·kg^(-1) with relative PEs of 12.4%and 3.35%,respectively.However,there was little difference between the primed CO_(2) emissions in Y+B500 and O+B500 treatments,which were measured to be-24.9 and-29.6 mg·C·kg^(-1) with relative PEs of-16.6%and-17.8%,respectively.Dissolved organic carbon(DOC)was significantly lower in the young poplar plantation soil than that in the old poplar plantation soil regardless of biochar amendment throughout the incubation,indicating greater C-limit of soil microorganisms in the young poplar plantation soil.Using ^(13)C isotope tracing,neither B300 nor B500 decreased native soil-derived DOC,which indicated that the negative B500-induced PEs were not due to a reduction in the availability of native soil-derived C.In conclusion,the response of biochar-induced PEs to poplar plantation age depends on biochar types while soil available C indirectly affects biochar-induced PEs.Further studies should focus on how the interactive effects between soil C availability and microbial community impacts biochar-induced PEs.展开更多
Most cherry orchards in China have low organic carbon content,though carbon is very important for plant growth.The changes in soil carbon and bacterial diversity were determined after different amounts of 12C-glucose ...Most cherry orchards in China have low organic carbon content,though carbon is very important for plant growth.The changes in soil carbon and bacterial diversity were determined after different amounts of 12C-glucose were added to the rhizosphere of Cerasus sachalinensis.Soil bacteria diversity was measured using high throughput sequencing,and bacteria containing 13C-glucose were identified using DNA-SIP methods.The results demonstrated that soil microbial biomass carbon(MBC)content and the soil respiratory rate were increased at 3 and 7 days after adding glucose.The soil organic carbon(SOC)content was decreased on the 7th day in the treatment where the added glucose-C was equivalent to the MBC content.SOC content was decreased on the 15th day after adding glucose-C equivalent to five times that of the soil MBC.Compared to the controls,the relative abundance of taxa at the phylum level displayed no significant change in the treatments with glucose-C added as 10%and equal amount of soil MBC 3–30 days after treatment.However,the relative abundance of Proteobacteria increased significantly in the treatment with the addition of glucose-C equivalent to five times of soil MBC.The main changes were observed in the bacteria in several genera including A4,Flavisolibacter,Aquicella,and Candidatus Solibacter.DNA-SIP results indicated that the relative abundance of the Proteobacteria and Pseudomonas was the highest;these were the primary bacteria phylum and genus,respectively,from day 3 to day 15.In conclusion,the changing pattern demonstrated that with the addition of more glucose,the range of the bacterial communities changed more.Proteobacteria and Pseudomonas may be the bacteria promoting priming effect.展开更多
This study examined the influence of semantic and phonological priming on L2 speech planning,as well as the difference between native and non-native speakers of English in terms of lemma activation.Two potential expla...This study examined the influence of semantic and phonological priming on L2 speech planning,as well as the difference between native and non-native speakers of English in terms of lemma activation.Two potential explanations for the contrast between the performance of L2 speakers and native controls were considered.The first of which was that L2 speakers’ phonological forms are activated before selection of syntactic frame occurred,whereas the reverse is true for native speakers.The second explanation posits that the organisation of the speech production procedure is fundamentally similar in native and L2 speakers,and the disparity in performance arises from difference in the levels of activation of stored items.The results of the present experiment suggest that lemma selection is indeed what drives syntactic frame selection.However,lemmas in L2 speakers can be primed through a chain of connections demonstrated as:L2 phonological form →L1 phonological form → L1 lemma.展开更多
It is not clear whether a shape memory effect （SME） can be realized by stress-induced α＇ martensite in metastable austenitic stainless steels although the stress-induced ε martensite in these materials can result...It is not clear whether a shape memory effect （SME） can be realized by stress-induced α＇ martensite in metastable austenitic stainless steels although the stress-induced ε martensite in these materials can result in the SME. To clarify this problem, the relationship between the shape recovery and the reverse transformation of the stress-induced ε and α＇ martensite in a 304 stainless steel was investigated. The results show that the stress-induced α＇ martensite can result in the SME when heating above 773 K. After deformation at 77 K and step heating or directly holding at 1073 K, two-stage shape recoveries below 440 K and above 773 K can be obtained due to the reverse transformation of the stress-induced ε martensite and α＇ martensite, respectively. After deformation at room temperature, the α＇ martensite produced can result in the SME only when directly holding at 1073 K. The intrusion of more dislocations before the formation of the α＇ martensite at room temperature than at 77 K is the reason that the α＇ martensite induced at room temperature cannot result in the SME in the case of slow heating. The recovered strains resulting from the stress-induced ε and α＇ martensite are proportional to the amounts of their reverse transformation, respectively.展开更多
基金supported by the Youth Talent Program of Fujian Academy of Agricultural Sciences,China(No.YC2019006)the External Cooperation Program of Fujian Academy of Agricultural Sciences,China(No.DWHZ-2022-20)+5 种基金the Foundation of Fujian Academy of Agricultural Sciences,China(No.CXTD2021012-2)the Special Fund of Fundamental Scientific Research at Nonprofit Research Institutions in Fujian,China(No.2022R1025001)the Special Fund of Fundamental Scientific Research at Nonprofit Research Institutions in Fujian,China(No.2022R1025001)the Natural Science Foundation of Fujian Province,China(No.2020J011358)the Modern Agro-Industry Technology Research System-Green Manure,China(No.CARS-22-G-01)“5511”Collaborative Innovation Engineering,China(No.XTCXGC2021009)。
文摘Nitrogen(N)priming is a microbially mediated biochemical process as affected by different incorporation practices.However,little information is known about the microbial mechanisms driving the response of N priming to co-operation of Chinese milk vetch(CMV,Astragalus sinicus L.)and different rates of chemical fertilizers in paddy soils in South China.Here,an anaerobic incubation experiment was conducted to study N priming effects(PE)and their relationships with soil microbial functional genes after CMV incorporation alone(M),co-incorporation of CMV with 100%(normal dosage)chemical fertilizers(MC100),and co-incorporation of CMV with 80% chemical fertilizers(MC80).Co-incorporation of CMV and chemical fertilizers enhanced the short-time scale(the first 20 d of incubation)positive PE of N,while no significant differences existed among the three treatments on day 60 or 90 of incubation(P>0.05).Compared with the M treatment,gross priming effect(GPE)in the MC100 and MC80 treatments significantly increased by 34.0% and 31.3%,respectively,and net priming effect(NPE)increased by 47.7% and 47.8%,respectively,during the first 20 d of incubation(P<0.05).This was likely attributed to soil nutrient availability and added substrate quality.The MC100 and MC80 treatments increased the gdhA gene abundance by 5.0% and 9.8%,increased the gdh2 gene abundance by 12.7% and 45.7%,and increased the nasB gene abundance by 9.5% and 41.4%,respectively,in comparison with the M treatment on day 20 of incubation.Correlation analyses indicated that soil microbial functional genes involved in N mineralization(gdhA and gdh2),assimilatory nitrate reduction(nasB),and nitrification(amoB)were significantly correlated with N priming under different incorporation practices during the incubation period(P<0.05).Thus,co-incorporation of CMV and chemical fertilizers can regulate soil microbial community functional gene structure,which may accelerate mineralization and assimilatory nitrate reduction and inhibit nitrification,thereby increasing the short-term positive PE of N in the present study.
基金the National Natural Science Foundation of China,No.30872132
文摘BACKGROUND： Dyslexic children exhibit reading ability unmatched to age, although they possess normal intelligence and are well educated. OBJECTIVE： To examine the performance of dyslexic children in Chinese characters visual recognition tasks and to investigate the relationship between priming effect in character recognition and dyslexia. DESIGN, TIME AND SETTING： A case-control study was performed at the Department of Children and Adolescent Health and Maternal Care, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology between March and June 2007. PARTICIPANTS： A total of 75 primary school students in grades 3 and 5 were selected from two primary schools in Wuhan City, Hubei province, China, and were assigned to three groups. （1） Reading disability （RD, n = 25）; （2） chronological age （CA） group （n = 25 normal readers that were intelligence quotient and age-matched to the RD group）; （3） reading level （RL） group （n = 25 normal readers that were intelligence quotient and RL-matched to the RD group）. All children were right-handed and had normal or corrected-to-normal vision. METHODS： Recognition of target characters was performed in each child using a masked prime paradigm. Recognition speed and accuracy of graphic, phonological, and semantic characters were examined. Simultaneously, data, with respect to response time for each target character and error rate, were recorded to calculate facilitation values （unrelated RT-related RT）. MAIN OUTCOME MEASURES： Response time, facilitation, and error rate in Chinese character recognition task were calculated. RESULTS： The baseline-adjusted facilitation of graphic, phonological, and semantic priming for dyslexic children was -0.010, -0.010, and 0.001, respectively. Dyslexic children displayed inhibition in graphic and phonological prime conditions. Facilitations under the three prime conditions were 0.026, 0.026, and 0.022 for the CA group. In the RL group, results were 0.062, 0.058, and 0.031 respectively. The differences of baseline-adjusted facilitation across the three groups were significant [F （2, 216） = 17.91, P 〈 0.01 ], whereas the main effect of prime condition IF （2, 216） = 0.49, P 〉 0.05] and the interaction of group x prime condition [F （4, 216） = 0.91, P 〉 0.05] were not significant. The error rate under the three prime conditions was 0.066, 0.077, and 0.079 for the RD group. As for the CA group, the results were 0.057, 0.071, and 0.074 accordingly, and in the RL group, the results were 0.119, 0.111, and 0.121, respectively. The difference of error rate across the three groups was significant （F = 6.61, P = 0.002）. The error rate was significantly greater in the RL group, compared with the CA and RD groups, while no significant difference existed between the RD and CA groups. CONCLUSION： Dyslexic children were slower to recognize target characters than normal readers, and did not exhibit significant prime effects in graphic and phonological primer condition. These results suggested that dyslexic children exhibited general deficits in phonological and graphic processing, and presented a different pattern in character recognition. These results could be interpreted by parallel-distributed processing models.
基金supported by the Natural Science Foundation of China(Grant numbers 31870465,31600377,31700462).
文摘In terrestrial ecosystems,deep soils(below 30 cm)are major organic carbon(C)pools.The labile carbon input could alter soil organic carbon(SOC)mineralization,resulting in priming effect(PE),which could be modified by nitrogen(N)availability,however,the underlying mechanism is unclear for deep soils,which complicates the prediction of deep soil C cycling in response to N deposition.A series of N applications with ^(13)C labeled glucose was set to investigate the effect of labile C and N on deep SOC mineralization.Microbial biomass,functional community,metabolic efficiency and enzyme activities were examined for their effects on SOC mineralization and PE.During incubation,glucose addition promoted SOC mineralization,resulting in positive PE.The magnitude of PE decreased significantly with increasing N.The N-regulated PE was not dependent on extracellular enzyme activities but was positively correlated with carbon use efficiency and negatively with metabolic quotient.Higher N levels resulted in higher microbial biomass and SOC-derived microbial biomass than lower N levels.These results suggest that the decline in the PE under high N availability was mainly controlled by higher microbial metabolic efficiency which allocated more C for growth.Structural equation modelling also revealed that microbial metabolic efficiency rather than enzyme activities was the main factor regulating the PE.The negative effect of additional N suggests that future N deposition could promote soil C sequestration.
基金This work was supported by National Priority Research and Development Program of China(2016YFD0600204)National Natural Science Foundation of China(41701264)+2 种基金Natural Science Foundation of Jiangsu Province,China(BK20170931)Natural Science Research Program(16KJB210005)Overseas Training Program and Priority Academic Program Development Funds(PAPD)of Jiangsu Higher Education Institutions.
文摘The priming effect(PE)induced by biochar provides a basis for evaluating its carbon(C)sequestration potential in soils.A 60 days’laboratory incubation was conducted,which involved the amendment of biochar(1%of soil mass)produced from rice straw at 300℃(B300)and 500℃(B500)to young(Y)and old(O)poplar plantation soils,with the aim of studying the responses of biochar-induced PEs to poplar plantation ages.This incubation included six treatments:Y+CK(control),Y+B300,Y+B500,O+CK,O+B300,and O+B500.Carbon dioxide(CO_(2))emissions were significantly increased(p<0.05)in the B300 amended soils,while it was decreased in the B500 amended soils compared to the CK.The primed CO_(2) emissions were 2.35 times higher in the Y+B300 than the O+B300 treatments,which was measured to be 18.6 and 5.56 mg C·kg^(-1) with relative PEs of 12.4%and 3.35%,respectively.However,there was little difference between the primed CO_(2) emissions in Y+B500 and O+B500 treatments,which were measured to be-24.9 and-29.6 mg·C·kg^(-1) with relative PEs of-16.6%and-17.8%,respectively.Dissolved organic carbon(DOC)was significantly lower in the young poplar plantation soil than that in the old poplar plantation soil regardless of biochar amendment throughout the incubation,indicating greater C-limit of soil microorganisms in the young poplar plantation soil.Using ^(13)C isotope tracing,neither B300 nor B500 decreased native soil-derived DOC,which indicated that the negative B500-induced PEs were not due to a reduction in the availability of native soil-derived C.In conclusion,the response of biochar-induced PEs to poplar plantation age depends on biochar types while soil available C indirectly affects biochar-induced PEs.Further studies should focus on how the interactive effects between soil C availability and microbial community impacts biochar-induced PEs.
基金This work was supported by the National Natural Science Foundation(Grant Nos.30871688,30900967,and 31572077)Liaoning Provincial Natural Science Foundation of China(Grant No.201602665)the High Level and Innovative Talents Program of Shenyang(Grant No.RC170201).
文摘Most cherry orchards in China have low organic carbon content,though carbon is very important for plant growth.The changes in soil carbon and bacterial diversity were determined after different amounts of 12C-glucose were added to the rhizosphere of Cerasus sachalinensis.Soil bacteria diversity was measured using high throughput sequencing,and bacteria containing 13C-glucose were identified using DNA-SIP methods.The results demonstrated that soil microbial biomass carbon(MBC)content and the soil respiratory rate were increased at 3 and 7 days after adding glucose.The soil organic carbon(SOC)content was decreased on the 7th day in the treatment where the added glucose-C was equivalent to the MBC content.SOC content was decreased on the 15th day after adding glucose-C equivalent to five times that of the soil MBC.Compared to the controls,the relative abundance of taxa at the phylum level displayed no significant change in the treatments with glucose-C added as 10%and equal amount of soil MBC 3–30 days after treatment.However,the relative abundance of Proteobacteria increased significantly in the treatment with the addition of glucose-C equivalent to five times of soil MBC.The main changes were observed in the bacteria in several genera including A4,Flavisolibacter,Aquicella,and Candidatus Solibacter.DNA-SIP results indicated that the relative abundance of the Proteobacteria and Pseudomonas was the highest;these were the primary bacteria phylum and genus,respectively,from day 3 to day 15.In conclusion,the changing pattern demonstrated that with the addition of more glucose,the range of the bacterial communities changed more.Proteobacteria and Pseudomonas may be the bacteria promoting priming effect.
文摘This study examined the influence of semantic and phonological priming on L2 speech planning,as well as the difference between native and non-native speakers of English in terms of lemma activation.Two potential explanations for the contrast between the performance of L2 speakers and native controls were considered.The first of which was that L2 speakers’ phonological forms are activated before selection of syntactic frame occurred,whereas the reverse is true for native speakers.The second explanation posits that the organisation of the speech production procedure is fundamentally similar in native and L2 speakers,and the disparity in performance arises from difference in the levels of activation of stored items.The results of the present experiment suggest that lemma selection is indeed what drives syntactic frame selection.However,lemmas in L2 speakers can be primed through a chain of connections demonstrated as:L2 phonological form →L1 phonological form → L1 lemma.
基金supported by the National Natural Science Foundation of China(Nos.51271128 and 51671138)
文摘It is not clear whether a shape memory effect （SME） can be realized by stress-induced α＇ martensite in metastable austenitic stainless steels although the stress-induced ε martensite in these materials can result in the SME. To clarify this problem, the relationship between the shape recovery and the reverse transformation of the stress-induced ε and α＇ martensite in a 304 stainless steel was investigated. The results show that the stress-induced α＇ martensite can result in the SME when heating above 773 K. After deformation at 77 K and step heating or directly holding at 1073 K, two-stage shape recoveries below 440 K and above 773 K can be obtained due to the reverse transformation of the stress-induced ε martensite and α＇ martensite, respectively. After deformation at room temperature, the α＇ martensite produced can result in the SME only when directly holding at 1073 K. The intrusion of more dislocations before the formation of the α＇ martensite at room temperature than at 77 K is the reason that the α＇ martensite induced at room temperature cannot result in the SME in the case of slow heating. The recovered strains resulting from the stress-induced ε and α＇ martensite are proportional to the amounts of their reverse transformation, respectively.
