The metabolic cycle firstly considered here is composed of a unique initial substrate, six enzymes, and five empty boxes to accommodate the substrates derived from the transformation of the initial substrate. This cyc...The metabolic cycle firstly considered here is composed of a unique initial substrate, six enzymes, and five empty boxes to accommodate the substrates derived from the transformation of the initial substrate. This cycle was considered as a pre-Closed Metabolic Cycle (CMC). Using this model, the influence of changing the kinetic constant values of any enzyme on the substrate concentration was explored. This model was transformed into an open metabolic cycle (OMC) by the input and output of two metabolites catalyzed by two external enzymes. In this case, the relative rates of input and output of metabolites were also examined;it can be concluded that the OMC cycles form delicate and fragile structures which can be theoretically disrupted, making them metabolically unfeasible.展开更多
Sustainable intensification of cultivated land use(SICLU) and large-scale operations(LSO) are widely acknowledged strategies for enhancing agricultural performance.However,the existing literature has faced challenges ...Sustainable intensification of cultivated land use(SICLU) and large-scale operations(LSO) are widely acknowledged strategies for enhancing agricultural performance.However,the existing literature has faced challenges in precisely defining SICLU and constructing comprehensive indicators,which has hindered the exploration of factors influencing LSO within the SICLU framework.To address this gap,we integrated self-efficacy theory into the design of an index framework for evaluating SICLU.We subsequently employed econometric models to analyze the significant factors that impact LSO.Our findings reveal that SICLU can be divided into four key dimensions:intensive management,efficient output,resource conservation,and ecological environment optimization.Furthermore,it is crucial to incorporate belief-based cognitive factors into the index system,as farmers’ understanding of fertilizer and pesticide application significantly influences their willingness to engage in LSO.Moreover,we identify grain market turnover as the most influential factor in promoting LSO,with single-factor contribution rates reaching 70.9% for cultivated land transfer willingness and 62.5% for the total planting areas.Interestingly,unlike irrigation and agricultural machinery inputs,increased labor inputs correspond to larger planting areas for farmers.This trend may be attributed to reduced labor availability because of rural labor migration,whereas the reduction in irrigation and agricultural input is contingent on innovations in production practices and the transfer of cultivated land management rights.Importantly,SICLU dynamically influences LSO,with each index related to SICLU having an optimal range that fosters LSO.These insights offer valuable guidance for policymakers,emphasizing farmers as their central focus,with the adjustment of input and output factors as a means to achieve LSO as the ultimate goal.In conclusion,we propose research avenues for further enriching the SICLU framework to ensure that it aligns with the specific characteristics of regional agricultural development.展开更多
For many years, Chinese students have been noticed to be doing remarkably well in some English tests concerning listening and reading skills,such as TOEFL(USA) and GRE(USA). But in some other English tests which focus...For many years, Chinese students have been noticed to be doing remarkably well in some English tests concerning listening and reading skills,such as TOEFL(USA) and GRE(USA). But in some other English tests which focus more on speaking and writing skills,e.g.TSE (Test of Spoken English, USA),BEC (Business English Certificate, GB) and some real communication situations, they are found to be much less proficient. In the meanwhile, many university graduates, who had already learned English展开更多
A nonlinear damped system with boundary input and output, which also has source term, is studied in this paper. It is proved that under some conditions the system has global solution and blow-up solution.
Four groups of field experiments including foliage dressing with a regular amount of rare earth elements (REEs), soil dressing with a regular amount of REEs, soil dressing with a triple regular amount of REEs and the ...Four groups of field experiments including foliage dressing with a regular amount of rare earth elements (REEs), soil dressing with a regular amount of REEs, soil dressing with a triple regular amount of REEs and the control were carried out in Panggezhuang Village, Daxing County, Beijing, where REE fertilizers are widely applied. The input and output fluxes of all kinds of REEs in the soil and plant system were measured using ICP-MS. The results show that the total amount of REEs carried by rain, snow, irrigation water, composite fertilizer and dust is at a very low level in the control field, which is only about 19.3 g·nm^(-1) per year. The amounts of REE input in the fields with application of extraneous REEs are much higher than that under control. The total amounts of REE input in the fields with foliage dressing and soil dressing are 9.7 and 106 times higher than that under control, respectively. However, the total outputs of REEs via wheat and infiltrated water are quite similar among the four experimental fields. Uptake of wheat is the main way of output and concentrations of REEs in different organs follow a descending order of roots>leaves>stems>crusts>seeds. Based on calculation, the amount of REE output is slightly higher than that of input in the control field, which implies that it is hard for REEs to accumulate in the soils without application of REE fertilizers. In the fields with the application of extraneous REEs, the amount of REEs in soils can increase with the increasing input of REEs. If REE-fertilizers are applied regularly via soil dressing with the ordinary amount, the concentrations of REEs in the surface soils may double in 159 years. The speed of REE accumulation with foliage dressing is much lower than that with soil dressing, and it needs 2008 years to double the concentrations of REEs in surface soils.展开更多
<div style="text-align:justify;"> <span style="font-family:Verdana;">We first recall the sufficient conditions for the existence of a periodic output of a modified Elman neural network ...<div style="text-align:justify;"> <span style="font-family:Verdana;">We first recall the sufficient conditions for the existence of a periodic output of a modified Elman neural network with a periodic input found by using Mawhin’s continuation theorem of coincidence degree theory. Using this result, we obtain sufficient conditions for the existence of a periodic output for an output hidden feedback Elman neural network with a periodic input. Examples illustrating these sufficient conditions are given.</span> </div>展开更多
This paper proposes a new switching scheme of switch fabric, which is named Multicast-enabled Protocol Agnostic Forwarding Engine (M-PAFE). M-PAFE is a central scheduling crossbar-based switch fabric with embedded Com...This paper proposes a new switching scheme of switch fabric, which is named Multicast-enabled Protocol Agnostic Forwarding Engine (M-PAFE). M-PAFE is a central scheduling crossbar-based switch fabric with embedded Combined Input and Output Queue from the queuing view. An extra switching path is dedicated for multicast cell processing in M-PAFE. And the simulation results are provided to evaluate the performance of M-PAFE in comparison with ESLIP, which is a well-known algorithm implemented in Cisco 12000 routers.展开更多
文摘The metabolic cycle firstly considered here is composed of a unique initial substrate, six enzymes, and five empty boxes to accommodate the substrates derived from the transformation of the initial substrate. This cycle was considered as a pre-Closed Metabolic Cycle (CMC). Using this model, the influence of changing the kinetic constant values of any enzyme on the substrate concentration was explored. This model was transformed into an open metabolic cycle (OMC) by the input and output of two metabolites catalyzed by two external enzymes. In this case, the relative rates of input and output of metabolites were also examined;it can be concluded that the OMC cycles form delicate and fragile structures which can be theoretically disrupted, making them metabolically unfeasible.
基金Under the auspices of National Natural Science Foundation of China(No.42071226,41671176)Taishan Scholars Youth Expert Support Plan of Shandong Province(No.TSQN202306183)。
文摘Sustainable intensification of cultivated land use(SICLU) and large-scale operations(LSO) are widely acknowledged strategies for enhancing agricultural performance.However,the existing literature has faced challenges in precisely defining SICLU and constructing comprehensive indicators,which has hindered the exploration of factors influencing LSO within the SICLU framework.To address this gap,we integrated self-efficacy theory into the design of an index framework for evaluating SICLU.We subsequently employed econometric models to analyze the significant factors that impact LSO.Our findings reveal that SICLU can be divided into four key dimensions:intensive management,efficient output,resource conservation,and ecological environment optimization.Furthermore,it is crucial to incorporate belief-based cognitive factors into the index system,as farmers’ understanding of fertilizer and pesticide application significantly influences their willingness to engage in LSO.Moreover,we identify grain market turnover as the most influential factor in promoting LSO,with single-factor contribution rates reaching 70.9% for cultivated land transfer willingness and 62.5% for the total planting areas.Interestingly,unlike irrigation and agricultural machinery inputs,increased labor inputs correspond to larger planting areas for farmers.This trend may be attributed to reduced labor availability because of rural labor migration,whereas the reduction in irrigation and agricultural input is contingent on innovations in production practices and the transfer of cultivated land management rights.Importantly,SICLU dynamically influences LSO,with each index related to SICLU having an optimal range that fosters LSO.These insights offer valuable guidance for policymakers,emphasizing farmers as their central focus,with the adjustment of input and output factors as a means to achieve LSO as the ultimate goal.In conclusion,we propose research avenues for further enriching the SICLU framework to ensure that it aligns with the specific characteristics of regional agricultural development.
文摘For many years, Chinese students have been noticed to be doing remarkably well in some English tests concerning listening and reading skills,such as TOEFL(USA) and GRE(USA). But in some other English tests which focus more on speaking and writing skills,e.g.TSE (Test of Spoken English, USA),BEC (Business English Certificate, GB) and some real communication situations, they are found to be much less proficient. In the meanwhile, many university graduates, who had already learned English
基金Supported by the National Science Foundation of China (60774014)the Science Foundation of Shanxi Province (2007011002)
文摘A nonlinear damped system with boundary input and output, which also has source term, is studied in this paper. It is proved that under some conditions the system has global solution and blow-up solution.
文摘Four groups of field experiments including foliage dressing with a regular amount of rare earth elements (REEs), soil dressing with a regular amount of REEs, soil dressing with a triple regular amount of REEs and the control were carried out in Panggezhuang Village, Daxing County, Beijing, where REE fertilizers are widely applied. The input and output fluxes of all kinds of REEs in the soil and plant system were measured using ICP-MS. The results show that the total amount of REEs carried by rain, snow, irrigation water, composite fertilizer and dust is at a very low level in the control field, which is only about 19.3 g·nm^(-1) per year. The amounts of REE input in the fields with application of extraneous REEs are much higher than that under control. The total amounts of REE input in the fields with foliage dressing and soil dressing are 9.7 and 106 times higher than that under control, respectively. However, the total outputs of REEs via wheat and infiltrated water are quite similar among the four experimental fields. Uptake of wheat is the main way of output and concentrations of REEs in different organs follow a descending order of roots>leaves>stems>crusts>seeds. Based on calculation, the amount of REE output is slightly higher than that of input in the control field, which implies that it is hard for REEs to accumulate in the soils without application of REE fertilizers. In the fields with the application of extraneous REEs, the amount of REEs in soils can increase with the increasing input of REEs. If REE-fertilizers are applied regularly via soil dressing with the ordinary amount, the concentrations of REEs in the surface soils may double in 159 years. The speed of REE accumulation with foliage dressing is much lower than that with soil dressing, and it needs 2008 years to double the concentrations of REEs in surface soils.
文摘<div style="text-align:justify;"> <span style="font-family:Verdana;">We first recall the sufficient conditions for the existence of a periodic output of a modified Elman neural network with a periodic input found by using Mawhin’s continuation theorem of coincidence degree theory. Using this result, we obtain sufficient conditions for the existence of a periodic output for an output hidden feedback Elman neural network with a periodic input. Examples illustrating these sufficient conditions are given.</span> </div>
文摘This paper proposes a new switching scheme of switch fabric, which is named Multicast-enabled Protocol Agnostic Forwarding Engine (M-PAFE). M-PAFE is a central scheduling crossbar-based switch fabric with embedded Combined Input and Output Queue from the queuing view. An extra switching path is dedicated for multicast cell processing in M-PAFE. And the simulation results are provided to evaluate the performance of M-PAFE in comparison with ESLIP, which is a well-known algorithm implemented in Cisco 12000 routers.