Mass transfer performance of gas–liquid two-phase flow at microscale is the basis of application of microreactor in gas–liquid reaction systems.At present,few researches on the mass transfer property of annular flow...Mass transfer performance of gas–liquid two-phase flow at microscale is the basis of application of microreactor in gas–liquid reaction systems.At present,few researches on the mass transfer property of annular flow have been reported.Therefore,the mass transfer mechanism and relationship of gas–liquid annular flow in a microfluidic cross-junction device are studied in the present study.We find that the main factors,i.e.,flow pattern,liquid film thickness,liquid hydraulic retention time,phase interface fluctuation,and gas flow vorticity,which influence the flow mass transfer property,are directly affected both by gas and liquid flow velocities.But the influences of gas and liquid velocities on different mass transfer influencing factors are different.Thereout,the fitting relationships between gas and liquid flow velocities and mass transfer influencing factors are established.By comparing the results from calculations using fitting equations and simulations,it shows that the fitting equations have relatively high degrees of accuracy.Finally,the Pareto front,namely the Pareto optimal solution set,of gas and liquid velocity conditions for the best flow mass transfer property is obtained using the method of multi-objective particle swarm optimization.It is proved that the mass transfer property of the gas–liquid two-phase flow can be obviously enhanced under the guidance of the obtained Pareto optimal solution set through experimental verification.展开更多
The traditional Chinese medicine of Radix Hedysari plays an important role in invigorating gas for ascending, benefiting blood for promoting production of fluid, and promoting circulation for removing obstruction in c...The traditional Chinese medicine of Radix Hedysari plays an important role in invigorating gas for ascending, benefiting blood for promoting production of fluid, and promoting circulation for removing obstruction in collaterals, which is consistent with the principle of treatment for osteoporosis. This study is designed to investigate the bioactive components on increasing peak bone mass (PBM) by exploring the spectrum-effect relationship between chromatography fingerprints and effect. Multiple indicators are selected to evaluate the pharmacological activity. In fingerprints, 21 common peaks are obtained, five of which are identified. Furthermore, gray relational analysis (GRA) is a quantitative method of gray system theory and is used to describe the correlation degree of common peaks and pharmacological activities with relational value. 21 components are then divided into three different regions, of which ononin and calycosin play an extremely significant role in increasing PBM. In addition, factor analysis and hierarchical cluster analysis (HCA) are used to screen the optimal producing area for Radix Hedysari. This provides a comprehensive and efficient method to improve the quality evaluation of Radix Hedysari, confirming the bioactive components for PBM-enhancement and further develop its medicinal value.展开更多
In postmodernist novel, the explanation of the relationship between fiction and reality is a distinctive feature, known as a playing game. In Continuity of Parks, the "game" is played through the application...In postmodernist novel, the explanation of the relationship between fiction and reality is a distinctive feature, known as a playing game. In Continuity of Parks, the "game" is played through the application of colors, settings, props, etc. with the plots' evolution. It is helpful to appreciate the postmodernist novel by analysing the relationship.展开更多
The scaling relationship between leaf area and total mass of plant has important implications for understanding resource allocations in the plant.The model of West,Brown and Enquist(WBE model)considers that a 3/4 scal...The scaling relationship between leaf area and total mass of plant has important implications for understanding resource allocations in the plant.The model of West,Brown and Enquist(WBE model)considers that a 3/4 scaling exponent of metabolic rate versus total mass to be optimal for each plant and has been confirmed numerous times.Although leaf area is a better proxy of the metabolic rate than leaf mass,few studies have focused on the scaling exponent of leaf area versus total mass and even fewer have discussed the diversification of this scaling exponent across different conditions.Here,I analyzed the scaling exponent of leaf area versus total mass of sample plots across world plants.I found that as the plant grows,it allocates fewer resources to photosynthetic tissues than expected by the WBE model.The results also empirically show that this scaling exponent varies significantly for different plant leaf habit,taxonomic class and geographic region.Therefore,leaf strategy in response to environmental pressure and constraint clearly plays a significant role.展开更多
As we know,new criticism is the post—world school of critical theory insists onthe intrinsic value of work of art and focusses on the individual work alone asan independent unit of meaning.It is opposed to the critic...As we know,new criticism is the post—world school of critical theory insists onthe intrinsic value of work of art and focusses on the individual work alone asan independent unit of meaning.It is opposed to the critical practice of bringing histori-cal of brographical data to bear on the anterpretation of a work.To the new critocs,poet-.ry was a special kind of discourse,a means of communicating feeling and thought thatwould not be expressed in any other kind of language.It differed qualitatively from thelanguage of science,or philosophy,but it converyed valid meanings.Such critics set outto define and formalize the qualities of poetic thought and languagege,using the techniqueof close reading with special emphasis on the implicative values of works and on the vari-ous function of figurative language—imagery,metaphor and symbol—in the work.展开更多
One hundred and ten samples of rainwater were collected for chemical analysis at the summit of Huangshan Mountain, a high-altitude site in East China, from July 2010 to June 2011. The volume-weighted-mean （VWM） pH f...One hundred and ten samples of rainwater were collected for chemical analysis at the summit of Huangshan Mountain, a high-altitude site in East China, from July 2010 to June 2011. The volume-weighted-mean （VWM） pH for the whole sampling period was 5.03. SO2- and Ca2＋ were the most abundant anion and cation, respectively. The ionic concentrations varied monthly with the highest concentrations in winter/spring and the lowest in summer. Evident inter-correlations were found among most ions, indicating the common sources for some species and fully mixing characteristics of the alpine precipitation chemistry. The VWM ratio of [SO]-]/[NO3] was 2.54, suggesting the acidity of rainwater comes from both nitric and sulfuric acids. Compared with contemporary observations at other alpine continental sites in China, the precipitation at Huangshan Mountain was the least polluted, with the lowest ionic concentrations. Trajectories to Huangshan Mountain on rainy days could be classified into six groups. The rainwater with influencing air masses originating in Mongolia was the most polluted with limited effect. The emissions of Jiangxi, Anhui, Zhejiang and Jiangsu provinces had a strong influence on the overall rain chemistry at Huangshan Mountain. The rainwater with influencing air masses from Inner Mongolia was heavily polluted by anthropogenic pollutants.展开更多
As one of the fastest developing regions in China, the middle-lower Yangtze River(MLYR) is vulnerable to floods and droughts. With obtained time series of annual highest water level(HWL), annual lowest water level(LWL...As one of the fastest developing regions in China, the middle-lower Yangtze River(MLYR) is vulnerable to floods and droughts. With obtained time series of annual highest water level(HWL), annual lowest water level(LWL) and the corresponding river discharges from three gauging stations in MLYR that covering the period 1987–2011, the current study evaluated the change characteristics of annual extreme water levels and the correlation with river discharges by using the methods of trend test, Mann-Whitney-Pettitt(MWP) test and double mass analysis. Major result indicated a decreasing/increasing trend for annual HWL/LWL of all stations in MLYR during the study period. A change point in 1999 was identified for annual HWL at the Hankou and Datong stations. The year 2006 was found to be the critical year that the relationship between annual extreme water levels and river discharges changed in the MLYR. With contrast to annual LWL in MLYR, further investigation revealed that the change characteristics of annual HWL were highly consistent with regional precipitation in the Yangtze River Basin, while the linkage with Three Gorges Dam(TGD) operation is not strong. Our observation also pointed out that the effect of serious down cutting of the riverbed and the enlargement of the cross-section area during the initial period of TGD operation caused the downward trend of the relationship between annual LWL and river discharge. Whereas, the relatively raised river water level before the flood season due to TGD regulation since 2006 explained for the changing upward trend of the relationship between annual HWL and river discharge.展开更多
Background and Purpose: Quality of life as an important factor in health is very important. This study is looking for an appropriate and effective treatment for improving quality of life. This research aims to study t...Background and Purpose: Quality of life as an important factor in health is very important. This study is looking for an appropriate and effective treatment for improving quality of life. This research aims to study the psychological effect of acceptance and commitment therapy (ACT) on quality of life of adult women suffering from obesity. Methods and Materials: This research is a kind of half-trail, with pattern of pre-test, post-test and group control. Statistical population includes all over-weight women with body mass index (BMI) range (30 - 40) who participated in family training sessions held in Shahin Shahr city. 40 patients who had the characteristics for sampling were selected and randomly placed in test and control groups (each group 20 people). Participants in each group before and after intervention quality of life questionnaire with 100 question sample World Health Organization Quality of Life (WHOQOL)-100 were evaluated. 12 sessions of acceptance and commitment therapy in group was used. The obtained data were analyzed with the use of Sciences Statistical Package for the Social (SPSS) 18 statistical software and methods of analysis of covariance. Findings: After selection of adult women having a BMI between 30 and 40 based on availability who had attended the meeting of family education, by invitation and voluntary, they were randomized into experimental and control groups. Intervention was done for experimental group. Due to the result of covariance analysis on the post-test stage, examination group showed significant improvement in variants physical health dimensions, level of independence in social and environmental relationships and spirituality (p < 0.01). Conclusion: According to the findings of this research based on the impact of acceptance and commitment intervention on promotion and improving in quality of life, this treatment can be used for improving the variants in women suffering from over-weight and obesity.展开更多
Noncovalent interactions between ligands and targeting proteins are essential for understanding molecular mechanisms of proteins.In this work,we investigated the interaction of Cytochrome c(Cyt c)with maltoligosacchar...Noncovalent interactions between ligands and targeting proteins are essential for understanding molecular mechanisms of proteins.In this work,we investigated the interaction of Cytochrome c(Cyt c)with maltoligosaccharides,namely maltose(Mal Ⅱ),maltotriose(Mal Ⅲ),maltotetraose(Mal Ⅳ),maltopentaose(Mal Ⅴ),maltohexaose(Mal Ⅵ)and maltoheptaose(Mal Ⅶ).Using electrospray ionization mass spetrometry(ESI-MS)assay,the 1:1 and 1:2 complexes formed by Cyt c with maltoligosaccharide ligand were observed.The corresponding association constants were calculated according to the deconvoluted spectra.The order of the relative binding affinities of the selected oligosaccharides with Cyt c were as MalⅢ>MalⅣ>MalⅡ>MalⅤ>MalⅥ>MalⅦ.The results indicated that the stability of noncovalent protein complexes was intimately correlated to the molecular structure of bound ligand.The relevant functional groups that could form H-bonds,electrostatic or hydrophobic forces with protein’s amino residues played an important role for the stability of protein complexes.In addition,the steric structure of ligand was also critical for an appropriate interaction with the binding pocket of proteins.展开更多
Continuous measurement of ambient PM10 was performed by TEOM at a university campus for about one year from 20 November 2007 to 29 October 2008 in Changsha city of Hunan province.Indoor PM10 and PM2.5 concentration we...Continuous measurement of ambient PM10 was performed by TEOM at a university campus for about one year from 20 November 2007 to 29 October 2008 in Changsha city of Hunan province.Indoor PM10 and PM2.5 concentration were measured by DustTrak simultaneously in order to describe the difference in concentration level and daily variations of particle mass concentration between different seasons,and to survey the influence of ambient particle on indoor air quality.During the survey period,the annual average PM10 concentration was found to be 117.63 μg/m3,with a mean value 121.88 μg/m3 in winter and 111.50 μg/m3 in spring.The temporal trend changed quickly from time to time,and the peak values were found in rush hours and in the evening.Ambient PM10 showed a good correlation with indoor PM10 and outdoor PM2.5 but not with indoor PM2.5.These results showed that PM10 was influenced by local source(such as traffic or fuel burning)and regional source.The correlation analysis has shown that ambient PM10 contributes substantial fraction to indoor PM10 but not to indoor PM2.5,which indicates other source may exist in the indoor environment.展开更多
A review of the art state was developed about the inflow relationships and their application for reservoir characterization. The theoretical development of the methodology for determining the damage effect using type-...A review of the art state was developed about the inflow relationships and their application for reservoir characterization. The theoretical development of the methodology for determining the damage effect using type-curves of the inflow relationships was shown. We show the process followed for achieve the geothermal type-curve affected with damage for reservoirs with mean salinities of 30000 ppm and temperatures up to 350℃. This type-curve was applied using measurement production data in a Mexican geothermal field. According with the obtained results is shown that the methodology for determining the damage effect using production measurements is a sure alternative for the damage effect calculation. It was used an alternative methodology in order to validate the damage presence and the obtained results were consistent. Last thing shows that both methodologies can be combined as a confident manner.展开更多
Einstein’s energy-momentum relationship is a formula that typifies the special theory of relativity (STR). According to the STR, when the velocity of a moving body increases, so does the mass of the body. The STR ass...Einstein’s energy-momentum relationship is a formula that typifies the special theory of relativity (STR). According to the STR, when the velocity of a moving body increases, so does the mass of the body. The STR asserts that the mass of a body depends of the velocity at which the body moves. However, when energy is imparted to a body, this relation holds because kinetic energy increases. When the motion of an electron in an atom is discussed at the level of classical quantum theory, the kinetic energy of the electron is increased due to the emission of energy. At this time, the relativistic energy of the electron decreases, and the mass of the electron also decreases. The STR is not applicable to an electron in an atom. This paper derives an energy-momentum relationship applicable to an electron in an atom. The formula which determines the mass of an electron in an atom is also derived by using that relationship.展开更多
背景:多项临床研究观察表明肥胖与骨质疏松症之间存在密切关系,但肥胖与骨质疏松症之间是否存在遗传因果效应尚不清楚。目的:利用大规模全基因组关联研究的汇总数据,通过孟德尔随机化分析探究肥胖和骨质疏松之间的关联。方法:肥胖数据...背景:多项临床研究观察表明肥胖与骨质疏松症之间存在密切关系,但肥胖与骨质疏松症之间是否存在遗传因果效应尚不清楚。目的:利用大规模全基因组关联研究的汇总数据,通过孟德尔随机化分析探究肥胖和骨质疏松之间的关联。方法:肥胖数据来自人体特征遗传调查(GIANT)和英国生物样本库(UKBB)的汇总统计数据。骨质疏松症的数据来自从骨质疏松症遗传因素联盟(GeFOS)获得的2种骨密度表型:全身骨密度和跟骨骨密度。逆方差加权法为主要分析方法,基于Egger回归的孟德尔随机化法(Mendelian randomization method based on Egger regression,MR-Egger)和加权中位数法作为补充方法来计算肥胖遗传变异与骨质疏松症之间的因果关联。采用敏感性分析来验证结果的可靠性,利用Cochran’s Q检验分析结果的异质性,利用MR-Egger截距检验分析结果的水平多效性,留一法评估合并的逆方差加权法估计值是否具有潜在影响的单核苷酸多态性。结果与结论:①肥胖对骨质疏松症的影响:除身体质量指数与前臂骨密度外,身体质量指数、腰臀比、经身体质量指数调整的腰臀比与全身骨密度、跟骨骨密度、前臂骨密度、腰椎骨密度及股骨颈骨密度两两之间呈正向因果关系;进一步Meta分析显示,肥胖会增加骨密度的风险(OR=1.08,95%CI:1.05-1.11,P<0.01);②骨质疏松症对肥胖的影响:除了前臂骨密度、腰椎骨密度作为暴露因素对肥胖有因果关系外,其他数据集均显示全身骨密度、跟骨骨密度、股骨颈骨密度与肥胖之间不呈现因果效应;进一步Meta分析显示,骨密度并不会增加肥胖的风险(OR=0.99,95%CI:0.98-1.01,P<0.01)。③结果证实:肥胖与骨质疏松之间存在因果关系,即肥胖可能是骨质疏松症的危险性因素,但未发现骨质疏松症对于肥胖的因果关联。展开更多
基金the National Natural Science Foundation of China(22178241,21908152 and 21978189)State Key Laboratory of Chemical Engineering,China(SKL-ChE-21A01).
文摘Mass transfer performance of gas–liquid two-phase flow at microscale is the basis of application of microreactor in gas–liquid reaction systems.At present,few researches on the mass transfer property of annular flow have been reported.Therefore,the mass transfer mechanism and relationship of gas–liquid annular flow in a microfluidic cross-junction device are studied in the present study.We find that the main factors,i.e.,flow pattern,liquid film thickness,liquid hydraulic retention time,phase interface fluctuation,and gas flow vorticity,which influence the flow mass transfer property,are directly affected both by gas and liquid flow velocities.But the influences of gas and liquid velocities on different mass transfer influencing factors are different.Thereout,the fitting relationships between gas and liquid flow velocities and mass transfer influencing factors are established.By comparing the results from calculations using fitting equations and simulations,it shows that the fitting equations have relatively high degrees of accuracy.Finally,the Pareto front,namely the Pareto optimal solution set,of gas and liquid velocity conditions for the best flow mass transfer property is obtained using the method of multi-objective particle swarm optimization.It is proved that the mass transfer property of the gas–liquid two-phase flow can be obviously enhanced under the guidance of the obtained Pareto optimal solution set through experimental verification.
基金supported by the National Natural Science Funds of China(Grant No.81703664)Science and Technology Funds of Lanzhou,China(Grant No.201603111)
文摘The traditional Chinese medicine of Radix Hedysari plays an important role in invigorating gas for ascending, benefiting blood for promoting production of fluid, and promoting circulation for removing obstruction in collaterals, which is consistent with the principle of treatment for osteoporosis. This study is designed to investigate the bioactive components on increasing peak bone mass (PBM) by exploring the spectrum-effect relationship between chromatography fingerprints and effect. Multiple indicators are selected to evaluate the pharmacological activity. In fingerprints, 21 common peaks are obtained, five of which are identified. Furthermore, gray relational analysis (GRA) is a quantitative method of gray system theory and is used to describe the correlation degree of common peaks and pharmacological activities with relational value. 21 components are then divided into three different regions, of which ononin and calycosin play an extremely significant role in increasing PBM. In addition, factor analysis and hierarchical cluster analysis (HCA) are used to screen the optimal producing area for Radix Hedysari. This provides a comprehensive and efficient method to improve the quality evaluation of Radix Hedysari, confirming the bioactive components for PBM-enhancement and further develop its medicinal value.
文摘In postmodernist novel, the explanation of the relationship between fiction and reality is a distinctive feature, known as a playing game. In Continuity of Parks, the "game" is played through the application of colors, settings, props, etc. with the plots' evolution. It is helpful to appreciate the postmodernist novel by analysing the relationship.
文摘The scaling relationship between leaf area and total mass of plant has important implications for understanding resource allocations in the plant.The model of West,Brown and Enquist(WBE model)considers that a 3/4 scaling exponent of metabolic rate versus total mass to be optimal for each plant and has been confirmed numerous times.Although leaf area is a better proxy of the metabolic rate than leaf mass,few studies have focused on the scaling exponent of leaf area versus total mass and even fewer have discussed the diversification of this scaling exponent across different conditions.Here,I analyzed the scaling exponent of leaf area versus total mass of sample plots across world plants.I found that as the plant grows,it allocates fewer resources to photosynthetic tissues than expected by the WBE model.The results also empirically show that this scaling exponent varies significantly for different plant leaf habit,taxonomic class and geographic region.Therefore,leaf strategy in response to environmental pressure and constraint clearly plays a significant role.
文摘As we know,new criticism is the post—world school of critical theory insists onthe intrinsic value of work of art and focusses on the individual work alone asan independent unit of meaning.It is opposed to the critical practice of bringing histori-cal of brographical data to bear on the anterpretation of a work.To the new critocs,poet-.ry was a special kind of discourse,a means of communicating feeling and thought thatwould not be expressed in any other kind of language.It differed qualitatively from thelanguage of science,or philosophy,but it converyed valid meanings.Such critics set outto define and formalize the qualities of poetic thought and languagege,using the techniqueof close reading with special emphasis on the implicative values of works and on the vari-ous function of figurative language—imagery,metaphor and symbol—in the work.
基金supported by funds from the Scientific Research Projects of High-level Talents of the Department of Human Resources and Social Security of Anhui Province (Grant No.2009Z019)the State Key Laboratory of Atmospheric Boundary Physics and Atmospheric Chemistry (Grant No.LAPC-KF-201105)
文摘One hundred and ten samples of rainwater were collected for chemical analysis at the summit of Huangshan Mountain, a high-altitude site in East China, from July 2010 to June 2011. The volume-weighted-mean （VWM） pH for the whole sampling period was 5.03. SO2- and Ca2＋ were the most abundant anion and cation, respectively. The ionic concentrations varied monthly with the highest concentrations in winter/spring and the lowest in summer. Evident inter-correlations were found among most ions, indicating the common sources for some species and fully mixing characteristics of the alpine precipitation chemistry. The VWM ratio of [SO]-]/[NO3] was 2.54, suggesting the acidity of rainwater comes from both nitric and sulfuric acids. Compared with contemporary observations at other alpine continental sites in China, the precipitation at Huangshan Mountain was the least polluted, with the lowest ionic concentrations. Trajectories to Huangshan Mountain on rainy days could be classified into six groups. The rainwater with influencing air masses originating in Mongolia was the most polluted with limited effect. The emissions of Jiangxi, Anhui, Zhejiang and Jiangsu provinces had a strong influence on the overall rain chemistry at Huangshan Mountain. The rainwater with influencing air masses from Inner Mongolia was heavily polluted by anthropogenic pollutants.
基金Under the auspices of the Fund of Key Laboratory of Watershed Geographic Sciences,Nanjing Institute of Geography and Limnology,Chinese Academy of Sciences(No.WSGS2015003)Fundamental Research Funds for the Central Universities(No.XDJK2016C093)National Natural Science Foundation of China(No.41571023)
文摘As one of the fastest developing regions in China, the middle-lower Yangtze River(MLYR) is vulnerable to floods and droughts. With obtained time series of annual highest water level(HWL), annual lowest water level(LWL) and the corresponding river discharges from three gauging stations in MLYR that covering the period 1987–2011, the current study evaluated the change characteristics of annual extreme water levels and the correlation with river discharges by using the methods of trend test, Mann-Whitney-Pettitt(MWP) test and double mass analysis. Major result indicated a decreasing/increasing trend for annual HWL/LWL of all stations in MLYR during the study period. A change point in 1999 was identified for annual HWL at the Hankou and Datong stations. The year 2006 was found to be the critical year that the relationship between annual extreme water levels and river discharges changed in the MLYR. With contrast to annual LWL in MLYR, further investigation revealed that the change characteristics of annual HWL were highly consistent with regional precipitation in the Yangtze River Basin, while the linkage with Three Gorges Dam(TGD) operation is not strong. Our observation also pointed out that the effect of serious down cutting of the riverbed and the enlargement of the cross-section area during the initial period of TGD operation caused the downward trend of the relationship between annual LWL and river discharge. Whereas, the relatively raised river water level before the flood season due to TGD regulation since 2006 explained for the changing upward trend of the relationship between annual HWL and river discharge.
文摘Background and Purpose: Quality of life as an important factor in health is very important. This study is looking for an appropriate and effective treatment for improving quality of life. This research aims to study the psychological effect of acceptance and commitment therapy (ACT) on quality of life of adult women suffering from obesity. Methods and Materials: This research is a kind of half-trail, with pattern of pre-test, post-test and group control. Statistical population includes all over-weight women with body mass index (BMI) range (30 - 40) who participated in family training sessions held in Shahin Shahr city. 40 patients who had the characteristics for sampling were selected and randomly placed in test and control groups (each group 20 people). Participants in each group before and after intervention quality of life questionnaire with 100 question sample World Health Organization Quality of Life (WHOQOL)-100 were evaluated. 12 sessions of acceptance and commitment therapy in group was used. The obtained data were analyzed with the use of Sciences Statistical Package for the Social (SPSS) 18 statistical software and methods of analysis of covariance. Findings: After selection of adult women having a BMI between 30 and 40 based on availability who had attended the meeting of family education, by invitation and voluntary, they were randomized into experimental and control groups. Intervention was done for experimental group. Due to the result of covariance analysis on the post-test stage, examination group showed significant improvement in variants physical health dimensions, level of independence in social and environmental relationships and spirituality (p < 0.01). Conclusion: According to the findings of this research based on the impact of acceptance and commitment intervention on promotion and improving in quality of life, this treatment can be used for improving the variants in women suffering from over-weight and obesity.
基金supported by the National Natural Science Foundation of China(Grant No.21675176)the Natural Science Foundation of Hubei Province(Grant No.2014CFA025)the Preferred Research Foundation for the Returned Overseas Scholars from Ministry of Human Resources and Social Security of the People’s Republic of China(Grant No.BZY14036)for financial supports.
文摘Noncovalent interactions between ligands and targeting proteins are essential for understanding molecular mechanisms of proteins.In this work,we investigated the interaction of Cytochrome c(Cyt c)with maltoligosaccharides,namely maltose(Mal Ⅱ),maltotriose(Mal Ⅲ),maltotetraose(Mal Ⅳ),maltopentaose(Mal Ⅴ),maltohexaose(Mal Ⅵ)and maltoheptaose(Mal Ⅶ).Using electrospray ionization mass spetrometry(ESI-MS)assay,the 1:1 and 1:2 complexes formed by Cyt c with maltoligosaccharide ligand were observed.The corresponding association constants were calculated according to the deconvoluted spectra.The order of the relative binding affinities of the selected oligosaccharides with Cyt c were as MalⅢ>MalⅣ>MalⅡ>MalⅤ>MalⅥ>MalⅦ.The results indicated that the stability of noncovalent protein complexes was intimately correlated to the molecular structure of bound ligand.The relevant functional groups that could form H-bonds,electrostatic or hydrophobic forces with protein’s amino residues played an important role for the stability of protein complexes.In addition,the steric structure of ligand was also critical for an appropriate interaction with the binding pocket of proteins.
基金Supported by Natural Science Foundation of China(50408019)Foundation for the Author of National Excellent Doctoral Dissertation of PR China(FANEDD200545)+1 种基金Folk Ying Tung Education Foundation(104006)Human Provincial Natural Science Foundation of China(06JJ1001)
文摘Continuous measurement of ambient PM10 was performed by TEOM at a university campus for about one year from 20 November 2007 to 29 October 2008 in Changsha city of Hunan province.Indoor PM10 and PM2.5 concentration were measured by DustTrak simultaneously in order to describe the difference in concentration level and daily variations of particle mass concentration between different seasons,and to survey the influence of ambient particle on indoor air quality.During the survey period,the annual average PM10 concentration was found to be 117.63 μg/m3,with a mean value 121.88 μg/m3 in winter and 111.50 μg/m3 in spring.The temporal trend changed quickly from time to time,and the peak values were found in rush hours and in the evening.Ambient PM10 showed a good correlation with indoor PM10 and outdoor PM2.5 but not with indoor PM2.5.These results showed that PM10 was influenced by local source(such as traffic or fuel burning)and regional source.The correlation analysis has shown that ambient PM10 contributes substantial fraction to indoor PM10 but not to indoor PM2.5,which indicates other source may exist in the indoor environment.
文摘A review of the art state was developed about the inflow relationships and their application for reservoir characterization. The theoretical development of the methodology for determining the damage effect using type-curves of the inflow relationships was shown. We show the process followed for achieve the geothermal type-curve affected with damage for reservoirs with mean salinities of 30000 ppm and temperatures up to 350℃. This type-curve was applied using measurement production data in a Mexican geothermal field. According with the obtained results is shown that the methodology for determining the damage effect using production measurements is a sure alternative for the damage effect calculation. It was used an alternative methodology in order to validate the damage presence and the obtained results were consistent. Last thing shows that both methodologies can be combined as a confident manner.
文摘Einstein’s energy-momentum relationship is a formula that typifies the special theory of relativity (STR). According to the STR, when the velocity of a moving body increases, so does the mass of the body. The STR asserts that the mass of a body depends of the velocity at which the body moves. However, when energy is imparted to a body, this relation holds because kinetic energy increases. When the motion of an electron in an atom is discussed at the level of classical quantum theory, the kinetic energy of the electron is increased due to the emission of energy. At this time, the relativistic energy of the electron decreases, and the mass of the electron also decreases. The STR is not applicable to an electron in an atom. This paper derives an energy-momentum relationship applicable to an electron in an atom. The formula which determines the mass of an electron in an atom is also derived by using that relationship.
文摘背景:多项临床研究观察表明肥胖与骨质疏松症之间存在密切关系,但肥胖与骨质疏松症之间是否存在遗传因果效应尚不清楚。目的:利用大规模全基因组关联研究的汇总数据,通过孟德尔随机化分析探究肥胖和骨质疏松之间的关联。方法:肥胖数据来自人体特征遗传调查(GIANT)和英国生物样本库(UKBB)的汇总统计数据。骨质疏松症的数据来自从骨质疏松症遗传因素联盟(GeFOS)获得的2种骨密度表型:全身骨密度和跟骨骨密度。逆方差加权法为主要分析方法,基于Egger回归的孟德尔随机化法(Mendelian randomization method based on Egger regression,MR-Egger)和加权中位数法作为补充方法来计算肥胖遗传变异与骨质疏松症之间的因果关联。采用敏感性分析来验证结果的可靠性,利用Cochran’s Q检验分析结果的异质性,利用MR-Egger截距检验分析结果的水平多效性,留一法评估合并的逆方差加权法估计值是否具有潜在影响的单核苷酸多态性。结果与结论:①肥胖对骨质疏松症的影响:除身体质量指数与前臂骨密度外,身体质量指数、腰臀比、经身体质量指数调整的腰臀比与全身骨密度、跟骨骨密度、前臂骨密度、腰椎骨密度及股骨颈骨密度两两之间呈正向因果关系;进一步Meta分析显示,肥胖会增加骨密度的风险(OR=1.08,95%CI:1.05-1.11,P<0.01);②骨质疏松症对肥胖的影响:除了前臂骨密度、腰椎骨密度作为暴露因素对肥胖有因果关系外,其他数据集均显示全身骨密度、跟骨骨密度、股骨颈骨密度与肥胖之间不呈现因果效应;进一步Meta分析显示,骨密度并不会增加肥胖的风险(OR=0.99,95%CI:0.98-1.01,P<0.01)。③结果证实:肥胖与骨质疏松之间存在因果关系,即肥胖可能是骨质疏松症的危险性因素,但未发现骨质疏松症对于肥胖的因果关联。
