Objective:To predict and analyze the potential Q-markers of Chuanxiong Chatiao Prescription,and the pharmacokinetic properties of pulvis and pills in vivo were studied,which provided a basis for the rational evaluatio...Objective:To predict and analyze the potential Q-markers of Chuanxiong Chatiao Prescription,and the pharmacokinetic properties of pulvis and pills in vivo were studied,which provided a basis for the rational evaluation of the phenomenon of“Different Dosage Forms of the Same Prescription”.Methods and Material:Q-markers analysis of Chuanxiong Chatiao Prescription based on the“Five Principles”(traceability and transmissibility,specificity,effectiveness,prescription compatibility and testability).The content determination method of Q-markers in Chuanxiong Chatiao Prescription was established by UPLC,and the content difference of Q-markers in the two dosage forms ware determined and compared.The Q-markers in rabbit plasma was determined by LC-MS/MS method,and the pharmacokinetic parameters of Q-markers in pulvis and pills were analyzed.Results:A total of 16 potential Q-markers from the“Five Principles”were used,nine components of tetramethylprazine,ferulic acid,glycyrrhizin,glycyrrhizic acid,luteolin,cimicifugoside,senkyunolideⅠ,isoimperatorin,nodakenin were identified as Q-markers of Chuanxiong Chatiao Presciption.The content of tetramethylprazine and other components in the pulvis form was found to be significantly higher than that in the pills,while the content of senkyunolideⅠwas lower than that in the pills,which may be related to the preparation process of the dosage form and the physicochemical properties of the components.Compared with pulvis,the Tmax and t_(1/2)of ferulic acid and other components in pills were significantly prolonged.To a certain extent,it can explain the classical theory of traditional Chinese medicine“Components in pulvis release quickly and take effect in fast-acting manner,while in pills release slowly and take effect in slow-acting”.Meanwhile,the Cmax and AUC0-t of tetramethylprazine and other components in pills were higher than those in pulvis,which showed unexpected pharmacokinetic characteristics,indicating the complexity of compounding and the importance of dosage form design.Conclusions:A method for the determination of Q-markers content was established by UPLC,which provide reference for the quality control of Chuanxiong Chatiao Prescription.In vivo studies have found the pharmacokinetic parameters indicate the absorption and distribution characteristics of pulvis and pills.However,it is also found that the release behavior of different components not only affected by the dosage form but also closely related to their own physical and chemical properties.展开更多
In the context of global emission reduction, the low-carbon sustainable development of the construction industry has become an important research content. With the vigorous development of new industrial technologies, ...In the context of global emission reduction, the low-carbon sustainable development of the construction industry has become an important research content. With the vigorous development of new industrial technologies, the application of prefabrication technology to buildings had become a mainstream. However, the research on the role of prefabricated technology in reducing building carbon emissions was not yet comprehensive, and the research on the relationship between prefabricated structure types and carbon emissions in the construction stage was not yet thorough. Guided by life cycle assessment (LCA), this paper used the scenario analysis method to set different working conditions for five different structural systems, and used SimaPro software to evaluate the carbon emissions of prefabricated buildings in order to clarify the carbon emissions of prefabricated buildings under different structural systems, and explore their impact mechanisms in depth. Finally, take the existing buildings in China as an empirical study, the results showed that: 1) The carbon emissions produced by the four common prefabricated structural systems were almost the same. Different structures had different requirements for the combination of components. The carbon emissions of individual buildings would be superimposed according to the carbon emission characteristics of various individual components to form the final total carbon emissions. 2) When the building structure system requires more combinations of components, the greater the amount of transportation invested in the transportation process, the more carbon emissions would be caused. In the calculation of all individual building construction stages, the carbon emissions generated by tower cranes almost exceed the sum of the carbon emissions of all mobile machinery. 3) Prefabricated shear wall structures and prefabricated frame-shear wall structures require a large amount of hoisting of prefabricated shear walls, so the carbon emissions of their mechanical equipment were also the highest.展开更多
[Objective] The aim was to study on effects of inorganic sodium salt in soil on concentration of zinc ion in different patterns. [Method] Tessier sequential extraction was used to study on effects of inorganic sodium ...[Objective] The aim was to study on effects of inorganic sodium salt in soil on concentration of zinc ion in different patterns. [Method] Tessier sequential extraction was used to study on effects of inorganic sodium salts (in different species and different concentrations) on concentration of zinc ion in different patterns. [Result] Different inorganic sodium salts had different effects on zinc form. Content of ex- changeable Zn would reduce if Na2CO3 or Na2SO4 was added and the content would increase if NaCI was added. Content of carbonate zinc, which was significantly influ- enced by Na2SO4, would increase if NaCI or Na2SO4 was added, and would decrease if Na2CO3 was added. For Zn bound to Fe-Mn oxides and organic matters, and residual Zn, the contents would decrease if NaCI or Na2SO4 was added and the decrease showed much more significantly if high concentration sodium salts were added. In addition, content of Zn bound to Fe-Mn oxides decreased if Na2CO3 was added. If low concentration Na2CO3 was added, Zn bound to organic matters and residual would increase in content but would lower if high concentration one was added. [Conclusion] The research provided references for measurement of heavy metal ion content in soil in different places.展开更多
Inorganic carbon forms and their influencing factors, mutual transformation and contribution to carbon cycling in the Jiaozhou Bay sediments were discussed. The results show that inorganic carbon in sediments could be...Inorganic carbon forms and their influencing factors, mutual transformation and contribution to carbon cycling in the Jiaozhou Bay sediments were discussed. The results show that inorganic carbon in sediments could be divided into five forms: NaCl form, NH3-H20 form, NaOH form, NH20H-HCl form and HCI form. Thereinto, NH2OH.HCl form and HCl form account for more than 70% of total inorganic carbon. There was close relationship among every form of inorganic carbon and their correlativity was clearly different with different sedimentary environment except the similar strong positive correlation among NH-OH-HCl form, HCl form and total inorganic carbon in all regions of the Jiaozhou Bay. All forms of inorganic carbon were influenced by organic carbon, pH, Eh, Es, nitrogen and phosphorus in sediments, but their influence had different characteristics in different regions. Every form of inorganic carbon transformed into each other continuously during early diagenesis of sediments and the common phenomenon was that NaCl form, NH3-H2O form, NaOH form and NH2OH-HCl form might transform into steady HCl form. NaCl form, NH3-H2O form, NaOH form and NH2OH-HCl form could participate in carbon recycle and they are potential carbon source; HCl form may be buried for a long time in sediments, and it may be one of the final resting places of atmospheric C02. Inorganic carbon which entered into sediments was about 4.98× 1010 g in the Jiaozhou Bay every year, in which about 1.47×1010 g of inorganic carbon might be buried for a long time and about 3.51 × 1010 g of inorganic carbon might return into seawater and take part in carbon recycling.展开更多
Iron in seawater is an essential trace metal for phytoplankton that plays an important role in the marine carbon cycle. But most studies focused on oceanic iron fertilization in high nutrient low chlorophyll (HNLC) ...Iron in seawater is an essential trace metal for phytoplankton that plays an important role in the marine carbon cycle. But most studies focused on oceanic iron fertilization in high nutrient low chlorophyll (HNLC) seawaters. A study of inorganic carbon (IC) forms and its influencing factors was presented in Liaodong Gulf sediments, and especially the influence of iron was discussed in detail. Inorganic carbon in Liaodong Gulf sediments was divided into five forms: NaCl, NH3·H2O, NaOH, NH2OH·HCl and HCl. The concentration of NaCl and NaOH forms were similar and they only occupied the minority of total inorganic carbon (TIC). However, NH3 ·H2O, NH2OH · HCl and HCl forms were the principal forms of TIC and accounted for more than 80% of TIC. Especially, the percentage of NH3·H2O form was much higher than that in the Changjiang River Estuary and Jiaozhou Bay sediments. All forms of inorganic carbon were influenced by organic carbon, pore water, iron, pH, redox potential (Eh) and sulfur potential(Es) in sediments, moreover, the influences had different characteristics for different IC forms. However, the redox reactions of iron affected mainly active IC forms. Iron had little effect on NH2OH· HCl and HCl forms of IC which were influenced mainly by pH. Iron had a stronger influence on NaCl, NaOH and NH3· H2O forms of IC ; the influence of Fe^2+ was higher than Fe^3+ and its effect on NH3 ·H2O form was stronger than on NaCl and NaOH forms.展开更多
Objectives: To determine the effective dosage and formulation of agkistrodon in collagen-induced arthritis(CIA) rats. Methods: CIA was induced by injection of collagen in complete/incomplete Freund's adjuvant. Ag...Objectives: To determine the effective dosage and formulation of agkistrodon in collagen-induced arthritis(CIA) rats. Methods: CIA was induced by injection of collagen in complete/incomplete Freund's adjuvant. Agkistrodon decoction, agkistrodon powder, and agkistrodon wine were administered daily starting from the onset of arthritis. Paw swelling degree was measured by using a volume-measuring instrument every 7 days after primary immunization. Arthritis index was measured and calculated using the "five scoring method" every 7 days. The levels of serum interleukin-1β(IL-1β) and type Ⅱ collagen Ig G antibodies were detected by enzyme-linked immunosorbent assay. Finally, all ankles were removed, and X-ray radiography was performed with In-vivo Imaging System FX. Samples were counterstained with hematoxylin and eosin for analysis. Results: Among the various dosage formulations of agkistrodon, high-dose powder, which was equivalent to an amount of 6 g/day in adults, showed better effects on the inhibition of joint swelling and reduction of arthritis index score. The relatively low levels of serum IL-1 and anti-type Ⅱ collagen Ig G antibodies, as well as the X-ray radiography and pathology results, further proved the superiority of the high-dose powder over the other formulations. The effect of decoction on inhibiting joint swelling was inversely proportional to the dosage. Other effects, such as reduction of arthritis index score and the levels of serum IL-1 and anti-type Ⅱ collagen Ig G antibodies, were directly proportional to the dosage. While the use of large dose agkistrodon wine led to negative effects. Conclusions: These data highlight the potential function of high-dose agkistrodon powder, which was equivalent to an amount of 6 g/day in adults. The powder can quickly relieve the symptoms of rheumatoid arthritis and prevent aggravation of disease, especially during the early period.展开更多
This paper presents equations for estimating limiting stand density for Z undulata plantations grown in hot desert areas of Raj asthan State in India. Five different stand level basal area projection models, belonging...This paper presents equations for estimating limiting stand density for Z undulata plantations grown in hot desert areas of Raj asthan State in India. Five different stand level basal area projection models, belonging to the path invariant algebraic difference form of a non-linear growth function, were also tested and compared. These models can be used to predict future basal area as a function of stand variables like dominant height and stem number per hectare and are necessary for reviewing different silvicultural treatment options. Data from 22 sample plots were used for modelling. An all possible growth intervals data structure was used. Both, qualitative and quantitative criteria were used to compare alternative models. The Akaike's information criteria differ- ence statistic was used to analyze the predictive ability of the models. Results show that the model proposed by Hui and Gadow performed best and hence this model is recommended for use in predicting basal area development in 12 undulata plantations in the study area. The data used were not from thinned stands, and hence the models may be less accurate when used for predictions when natural mortality is very significant.展开更多
Benzoic acid as a source of proton is widely used in the technology of manufacture of proton exchanged ( PE) waveguide .But the diffusing speed of proton is too fast to make the waveguide stable in the pure benzoic ac...Benzoic acid as a source of proton is widely used in the technology of manufacture of proton exchanged ( PE) waveguide .But the diffusing speed of proton is too fast to make the waveguide stable in the pure benzoic acid. The characteristic of waveguide is improved with mixture of benzoic acid and lithium benzoate .展开更多
Aims To explore the pattern of the leaf functional traits of shrub species along a latitudinal gradient in eastern China and determine the driv-ing factors of leaf trait variation at a large scale.Methods We investiga...Aims To explore the pattern of the leaf functional traits of shrub species along a latitudinal gradient in eastern China and determine the driv-ing factors of leaf trait variation at a large scale.Methods We investigated the leaf thickness(LT),leaf area(LA),specific leaf area(SLA)and leaf dry mass content(LDMC)of 185 shrub species from 13 sites across eastern China.The trends of these four-leaf traits were ana-lyzed with respect to latitude,and the differences between different life forms(e.g.,evergreen and deciduous)and habitats(e.g.,understory and typical)were compared.We quantified the effects of the plant life forms and environmental factors on the leaf traits via mixed-model analyses.Important Findings The LT and LA decreased,whilst and the LDMC increased,as the latitude increased,and significant differences in these traits were observed between the different plant life forms.The LT and LA were smaller,whereas the SLA and LDMC were larger in decidu-ous shrubs than in evergreen shrubs.Among the different habitats,the LA and SLA were larger,while the LDMC was smaller in under-story shrubs than in typical shrub species.These results indicate that typical shrub species are better adapted to drier environments,as indicated by a reduced LT and increased LDMC.Furthermore,general linear models showed that variations in the four-leaf traits with respect to latitude were mainly caused by a shift in plant life forms.展开更多
In this paper, we present an explicit and computable lower bound for the first eigenvalue of birth-death processes with killing. This estimate is qualitatively sharp for birth-death processes without killing. We also ...In this paper, we present an explicit and computable lower bound for the first eigenvalue of birth-death processes with killing. This estimate is qualitatively sharp for birth-death processes without killing. We also establish an approximation procedure for the first eigenvalue of the birth-death process with killing by an increasing principal eigenvalue sequence of some birth-death processes without killing. Some applications of our results are illustrated by many examples.展开更多
基金supported by Chinese Medicine Pharmaceutical Key Discipline of Shaanxi province(No.303061107)National key Research and Development plan(No.2018-YFC1706904)+1 种基金Discipline Innovation team Project of Shaanxi University of Chinese Medicine(No.2019-YL11)Shaanxi Province Key subject of pharmacy engineering of Shaanxi Provincial Traditional Chinese Medicine administration(No.2017001).
文摘Objective:To predict and analyze the potential Q-markers of Chuanxiong Chatiao Prescription,and the pharmacokinetic properties of pulvis and pills in vivo were studied,which provided a basis for the rational evaluation of the phenomenon of“Different Dosage Forms of the Same Prescription”.Methods and Material:Q-markers analysis of Chuanxiong Chatiao Prescription based on the“Five Principles”(traceability and transmissibility,specificity,effectiveness,prescription compatibility and testability).The content determination method of Q-markers in Chuanxiong Chatiao Prescription was established by UPLC,and the content difference of Q-markers in the two dosage forms ware determined and compared.The Q-markers in rabbit plasma was determined by LC-MS/MS method,and the pharmacokinetic parameters of Q-markers in pulvis and pills were analyzed.Results:A total of 16 potential Q-markers from the“Five Principles”were used,nine components of tetramethylprazine,ferulic acid,glycyrrhizin,glycyrrhizic acid,luteolin,cimicifugoside,senkyunolideⅠ,isoimperatorin,nodakenin were identified as Q-markers of Chuanxiong Chatiao Presciption.The content of tetramethylprazine and other components in the pulvis form was found to be significantly higher than that in the pills,while the content of senkyunolideⅠwas lower than that in the pills,which may be related to the preparation process of the dosage form and the physicochemical properties of the components.Compared with pulvis,the Tmax and t_(1/2)of ferulic acid and other components in pills were significantly prolonged.To a certain extent,it can explain the classical theory of traditional Chinese medicine“Components in pulvis release quickly and take effect in fast-acting manner,while in pills release slowly and take effect in slow-acting”.Meanwhile,the Cmax and AUC0-t of tetramethylprazine and other components in pills were higher than those in pulvis,which showed unexpected pharmacokinetic characteristics,indicating the complexity of compounding and the importance of dosage form design.Conclusions:A method for the determination of Q-markers content was established by UPLC,which provide reference for the quality control of Chuanxiong Chatiao Prescription.In vivo studies have found the pharmacokinetic parameters indicate the absorption and distribution characteristics of pulvis and pills.However,it is also found that the release behavior of different components not only affected by the dosage form but also closely related to their own physical and chemical properties.
文摘In the context of global emission reduction, the low-carbon sustainable development of the construction industry has become an important research content. With the vigorous development of new industrial technologies, the application of prefabrication technology to buildings had become a mainstream. However, the research on the role of prefabricated technology in reducing building carbon emissions was not yet comprehensive, and the research on the relationship between prefabricated structure types and carbon emissions in the construction stage was not yet thorough. Guided by life cycle assessment (LCA), this paper used the scenario analysis method to set different working conditions for five different structural systems, and used SimaPro software to evaluate the carbon emissions of prefabricated buildings in order to clarify the carbon emissions of prefabricated buildings under different structural systems, and explore their impact mechanisms in depth. Finally, take the existing buildings in China as an empirical study, the results showed that: 1) The carbon emissions produced by the four common prefabricated structural systems were almost the same. Different structures had different requirements for the combination of components. The carbon emissions of individual buildings would be superimposed according to the carbon emission characteristics of various individual components to form the final total carbon emissions. 2) When the building structure system requires more combinations of components, the greater the amount of transportation invested in the transportation process, the more carbon emissions would be caused. In the calculation of all individual building construction stages, the carbon emissions generated by tower cranes almost exceed the sum of the carbon emissions of all mobile machinery. 3) Prefabricated shear wall structures and prefabricated frame-shear wall structures require a large amount of hoisting of prefabricated shear walls, so the carbon emissions of their mechanical equipment were also the highest.
基金Supported by National Natural Science Foundation of China (40973078)Tianjin Normal University Project (5RL083)~~
文摘[Objective] The aim was to study on effects of inorganic sodium salt in soil on concentration of zinc ion in different patterns. [Method] Tessier sequential extraction was used to study on effects of inorganic sodium salts (in different species and different concentrations) on concentration of zinc ion in different patterns. [Result] Different inorganic sodium salts had different effects on zinc form. Content of ex- changeable Zn would reduce if Na2CO3 or Na2SO4 was added and the content would increase if NaCI was added. Content of carbonate zinc, which was significantly influ- enced by Na2SO4, would increase if NaCI or Na2SO4 was added, and would decrease if Na2CO3 was added. For Zn bound to Fe-Mn oxides and organic matters, and residual Zn, the contents would decrease if NaCI or Na2SO4 was added and the decrease showed much more significantly if high concentration sodium salts were added. In addition, content of Zn bound to Fe-Mn oxides decreased if Na2CO3 was added. If low concentration Na2CO3 was added, Zn bound to organic matters and residual would increase in content but would lower if high concentration one was added. [Conclusion] The research provided references for measurement of heavy metal ion content in soil in different places.
基金The opening foundation of the Key Laboratory of Marine Sedimentology & Environmental Geology,SOA under contract No. MASEG200606Creative Research Groups by NSFC under contract No.40821004+1 种基金the National Key Project for Basic Research of China under contract No. 2007CB407305the "100 Talents Project" of the Chinese Academy of Sciences
文摘Inorganic carbon forms and their influencing factors, mutual transformation and contribution to carbon cycling in the Jiaozhou Bay sediments were discussed. The results show that inorganic carbon in sediments could be divided into five forms: NaCl form, NH3-H20 form, NaOH form, NH20H-HCl form and HCI form. Thereinto, NH2OH.HCl form and HCl form account for more than 70% of total inorganic carbon. There was close relationship among every form of inorganic carbon and their correlativity was clearly different with different sedimentary environment except the similar strong positive correlation among NH-OH-HCl form, HCl form and total inorganic carbon in all regions of the Jiaozhou Bay. All forms of inorganic carbon were influenced by organic carbon, pH, Eh, Es, nitrogen and phosphorus in sediments, but their influence had different characteristics in different regions. Every form of inorganic carbon transformed into each other continuously during early diagenesis of sediments and the common phenomenon was that NaCl form, NH3-H2O form, NaOH form and NH2OH-HCl form might transform into steady HCl form. NaCl form, NH3-H2O form, NaOH form and NH2OH-HCl form could participate in carbon recycle and they are potential carbon source; HCl form may be buried for a long time in sediments, and it may be one of the final resting places of atmospheric C02. Inorganic carbon which entered into sediments was about 4.98× 1010 g in the Jiaozhou Bay every year, in which about 1.47×1010 g of inorganic carbon might be buried for a long time and about 3.51 × 1010 g of inorganic carbon might return into seawater and take part in carbon recycling.
文摘Iron in seawater is an essential trace metal for phytoplankton that plays an important role in the marine carbon cycle. But most studies focused on oceanic iron fertilization in high nutrient low chlorophyll (HNLC) seawaters. A study of inorganic carbon (IC) forms and its influencing factors was presented in Liaodong Gulf sediments, and especially the influence of iron was discussed in detail. Inorganic carbon in Liaodong Gulf sediments was divided into five forms: NaCl, NH3·H2O, NaOH, NH2OH·HCl and HCl. The concentration of NaCl and NaOH forms were similar and they only occupied the minority of total inorganic carbon (TIC). However, NH3 ·H2O, NH2OH · HCl and HCl forms were the principal forms of TIC and accounted for more than 80% of TIC. Especially, the percentage of NH3·H2O form was much higher than that in the Changjiang River Estuary and Jiaozhou Bay sediments. All forms of inorganic carbon were influenced by organic carbon, pore water, iron, pH, redox potential (Eh) and sulfur potential(Es) in sediments, moreover, the influences had different characteristics for different IC forms. However, the redox reactions of iron affected mainly active IC forms. Iron had little effect on NH2OH· HCl and HCl forms of IC which were influenced mainly by pH. Iron had a stronger influence on NaCl, NaOH and NH3· H2O forms of IC ; the influence of Fe^2+ was higher than Fe^3+ and its effect on NH3 ·H2O form was stronger than on NaCl and NaOH forms.
基金Supported by the Traditional Chinese Medicine Scientific Research Fund of Zhejiang Province,China(No.2013ZA063 and No.2012ZB062)the Key Scientific and Technological Innovation Team Plan of Zhejiang Province,China(No.2009R50042-002)the Third Level of 151 Talents Project of Zhejiang Province,China
文摘Objectives: To determine the effective dosage and formulation of agkistrodon in collagen-induced arthritis(CIA) rats. Methods: CIA was induced by injection of collagen in complete/incomplete Freund's adjuvant. Agkistrodon decoction, agkistrodon powder, and agkistrodon wine were administered daily starting from the onset of arthritis. Paw swelling degree was measured by using a volume-measuring instrument every 7 days after primary immunization. Arthritis index was measured and calculated using the "five scoring method" every 7 days. The levels of serum interleukin-1β(IL-1β) and type Ⅱ collagen Ig G antibodies were detected by enzyme-linked immunosorbent assay. Finally, all ankles were removed, and X-ray radiography was performed with In-vivo Imaging System FX. Samples were counterstained with hematoxylin and eosin for analysis. Results: Among the various dosage formulations of agkistrodon, high-dose powder, which was equivalent to an amount of 6 g/day in adults, showed better effects on the inhibition of joint swelling and reduction of arthritis index score. The relatively low levels of serum IL-1 and anti-type Ⅱ collagen Ig G antibodies, as well as the X-ray radiography and pathology results, further proved the superiority of the high-dose powder over the other formulations. The effect of decoction on inhibiting joint swelling was inversely proportional to the dosage. Other effects, such as reduction of arthritis index score and the levels of serum IL-1 and anti-type Ⅱ collagen Ig G antibodies, were directly proportional to the dosage. While the use of large dose agkistrodon wine led to negative effects. Conclusions: These data highlight the potential function of high-dose agkistrodon powder, which was equivalent to an amount of 6 g/day in adults. The powder can quickly relieve the symptoms of rheumatoid arthritis and prevent aggravation of disease, especially during the early period.
基金the State Forest Department,Rajasthan for providing financial support for conducting this study and to their officials for rendering necessary assistance during fieldwork
文摘This paper presents equations for estimating limiting stand density for Z undulata plantations grown in hot desert areas of Raj asthan State in India. Five different stand level basal area projection models, belonging to the path invariant algebraic difference form of a non-linear growth function, were also tested and compared. These models can be used to predict future basal area as a function of stand variables like dominant height and stem number per hectare and are necessary for reviewing different silvicultural treatment options. Data from 22 sample plots were used for modelling. An all possible growth intervals data structure was used. Both, qualitative and quantitative criteria were used to compare alternative models. The Akaike's information criteria differ- ence statistic was used to analyze the predictive ability of the models. Results show that the model proposed by Hui and Gadow performed best and hence this model is recommended for use in predicting basal area development in 12 undulata plantations in the study area. The data used were not from thinned stands, and hence the models may be less accurate when used for predictions when natural mortality is very significant.
基金This work is supported by science and technology bureau of Shanghai under the fundation of special project of Optical Science and Technology.
文摘Benzoic acid as a source of proton is widely used in the technology of manufacture of proton exchanged ( PE) waveguide .But the diffusing speed of proton is too fast to make the waveguide stable in the pure benzoic acid. The characteristic of waveguide is improved with mixture of benzoic acid and lithium benzoate .
基金Grants were received from the National Natural Science Foundation of China(31470498 and 31330012)the Chinese National Basic Research Program(2015CB954201 and 2014CB954303)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA05050701).
文摘Aims To explore the pattern of the leaf functional traits of shrub species along a latitudinal gradient in eastern China and determine the driv-ing factors of leaf trait variation at a large scale.Methods We investigated the leaf thickness(LT),leaf area(LA),specific leaf area(SLA)and leaf dry mass content(LDMC)of 185 shrub species from 13 sites across eastern China.The trends of these four-leaf traits were ana-lyzed with respect to latitude,and the differences between different life forms(e.g.,evergreen and deciduous)and habitats(e.g.,understory and typical)were compared.We quantified the effects of the plant life forms and environmental factors on the leaf traits via mixed-model analyses.Important Findings The LT and LA decreased,whilst and the LDMC increased,as the latitude increased,and significant differences in these traits were observed between the different plant life forms.The LT and LA were smaller,whereas the SLA and LDMC were larger in decidu-ous shrubs than in evergreen shrubs.Among the different habitats,the LA and SLA were larger,while the LDMC was smaller in under-story shrubs than in typical shrub species.These results indicate that typical shrub species are better adapted to drier environments,as indicated by a reduced LT and increased LDMC.Furthermore,general linear models showed that variations in the four-leaf traits with respect to latitude were mainly caused by a shift in plant life forms.
文摘In this paper, we present an explicit and computable lower bound for the first eigenvalue of birth-death processes with killing. This estimate is qualitatively sharp for birth-death processes without killing. We also establish an approximation procedure for the first eigenvalue of the birth-death process with killing by an increasing principal eigenvalue sequence of some birth-death processes without killing. Some applications of our results are illustrated by many examples.