The struetural effect of the conjugative system(C)with carbonyl-imino bridges has been studied.The results show that:In the conjugated system(C),there is no electronic absorption peak attributable to the whole system,...The struetural effect of the conjugative system(C)with carbonyl-imino bridges has been studied.The results show that:In the conjugated system(C),there is no electronic absorption peak attributable to the whole system,but there are three π-π* bands each nt which displays chacactecistics of its own independently.These indicate that the two bridges-carbonyl-and-imino-can block the tlanSmlSSion of the conjngative polarization of the whole system,so as to form three segments,this is verified by means of chemical synthesis and degradation.展开更多
Rhodamine B-ethylenediamine-beta-cyclodextrins (RhB-beta-CDen) and rhodamine B-beta-cyclodextrins (RhB-beta-CD) form inclusion complexes with many vip molecules, which can be used as nucleic acid probe. In this pape...Rhodamine B-ethylenediamine-beta-cyclodextrins (RhB-beta-CDen) and rhodamine B-beta-cyclodextrins (RhB-beta-CD) form inclusion complexes with many vip molecules, which can be used as nucleic acid probe. In this paper we determined the most stable conformations of RhB-beta-CDen and RhB-beta-CD by molecular mechanics and dynamics simulation. The interaction between RhB-beta-CDen and two vip molecules, 1-borneol and cyclohexanol, have been investigated both theoretically and experimentally. The results show that the interaction between borneol and RhB-beta-CDen is stronger than that between cyclohexanol and RhB-beta-CDen.展开更多
With the support of the Ministry of Science and Technology (MOST), scientists from the Chinese Academy of Atomic Energy and the Chinese Academy of Sciences (CAS) formally kicked off a new project to look into clean nu...With the support of the Ministry of Science and Technology (MOST), scientists from the Chinese Academy of Atomic Energy and the Chinese Academy of Sciences (CAS) formally kicked off a new project to look into clean nuclear energy on September 27th in Beijing. The study, known as the accelerator-driven system of clean展开更多
Second language acquisition can not be understood without addressing the interaction between language and cognition. Cognitive theory can extend to describe learning strategies as complex cognitive skills. Theoretical...Second language acquisition can not be understood without addressing the interaction between language and cognition. Cognitive theory can extend to describe learning strategies as complex cognitive skills. Theoretical developments in Anderson’s production systems cover a broader range of behavior than other theories, including comprehension and production of oral and written texts as well as comprehension, problem solving, and verbal learning.Thus Anderson’s cognitive theory can be served as a rationale for learning strategy studies in second language acquisition.展开更多
This paper discusses the stability structure and the bifurcation of phase path characteristics of synoptic scale system.The analytic results show that the catastrophe of the synoptic scale disturbance may be caused by...This paper discusses the stability structure and the bifurcation of phase path characteristics of synoptic scale system.The analytic results show that the catastrophe of the synoptic scale disturbance may be caused by the nonlinear effects of barotropic and baroclinic instability and advection of ambient large-scale flow.Also, foregoing nonlinear effects on the speed of development and decay of the system are presented in the processes deviating from or approaching to equilibrium state.It has been found that there is a resonance phenomenon between the time-oscillation of heat source and the atmospheric disturbance.展开更多
Seven homologous series p-A=B-C_6H_4(CH=CH)_nX=Y (A=B: NO_2, X=Y: CHO, COMe, CN, NO_2; A=B: CN, X=Y: CHO, CN; A=B: H, X=Y: NO_2) were synthesized, the effect of opposite terminal groups in phenylpolyenic conjugative s...Seven homologous series p-A=B-C_6H_4(CH=CH)_nX=Y (A=B: NO_2, X=Y: CHO, COMe, CN, NO_2; A=B: CN, X=Y: CHO, CN; A=B: H, X=Y: NO_2) were synthesized, the effect of opposite terminal groups in phenylpolyenic conjugative systems has been studied by means of UV, XPS, ^(13) C NMR and quantum chemical calculation. The results show that: 1. There exists the effect of opposite terminal groups exists in phenylpolyenic and other aromatic conjugative systems. 2. When A=B and X=Y are the same, the group (-X=Y) connected at polyenic chain is a terminal group, while the other is an opposite terminal group. When the two groups are different, the one with weaker conjugative power plays the role of the opposite terminal group. 3. The effect of opposite terminal groups increases successively in the order of CN, COMe, CHO, NO_2 and can be quantita- tively described with substitute equivalent △N_s. Theλ_(max) of compound containing an opposite terminal group can be calculated by the homologous equation 10^(-4) =a+b/(1/2)^(2/N＇^(-S)_a), most of the calculated values are in agreement with experiment results.展开更多
Background A voluntary procedure for reporting adverse drug reactions (ADRs) was formally put in place in 1989. However,only a small proportion of ADR reports are actually forwarded to the national monitoring center. ...Background A voluntary procedure for reporting adverse drug reactions (ADRs) was formally put in place in 1989. However,only a small proportion of ADR reports are actually forwarded to the national monitoring center. To identify the reasons for underreporting,the authors investigated the awareness and attitudes of healthcare professionals (doctors,nurses,and administrators) toward the ADR system in China. In addition,the authors sought to formulate approaches to improve the current ADR reporting system.Methods Structured interviews were carried out in 16 hospitals selected from 27 municipal hospitals in Wuhan,Hubei Province,China. A questionnaire survey of a stratified random sample of approximately 15% of healthcare professionals in each selected hospital was conducted during February to March 2003.Results The response rate of this survey was 85%. One thousand six hundred and fifty-three questionnaires were used in the final analysis. Only 2.7% of the healthcare professionals had a correct understanding to the definition of ADR. Eighty-nine point two percent of the healthcare professionals had encountered ADRs. Ninety-four percent of them were aware of the need to report these to the ADR monitoring center. However,only 28.5% of doctors,22.8% of nurses,and 29.7% of administrators actually submitted a report. For the most part,they reported ADRs to the hospital pharmacy (66.0%),to other departments in the hospital (72.5%),and to the pharmaceutical industry (23.0%),rather than to the national monitoring center (2.9%) or regional monitoring center (9.5%). Severe or rare ADRs and ADRs to new products were generally perceived to be significant enough to report. Sixty-two point one percent of the healthcare professionals had encountered ADRs,yet not reported them to anybody. The major reasons for not reporting included no knowledge of the reporting procedure (71.4%),unavailability of the reporting center mailing address (67.9%),unavailability of the ADR report form (60.4%),lack of knowledge of the existence of a national ADR reporting system (52.2%),and belief that the ADR in question was already well known (44.1%). Conclusions Healthcare professionals in Wuhan,China have little basic knowledge of ADR and of the voluntary reporting system. The main reasons for underreporting were lack of basic knowledge about ADRs and the voluntary reporting procedure. Education and training of healthcare professionals is needed to improve the current ADR reporting system.展开更多
文摘The struetural effect of the conjugative system(C)with carbonyl-imino bridges has been studied.The results show that:In the conjugated system(C),there is no electronic absorption peak attributable to the whole system,but there are three π-π* bands each nt which displays chacactecistics of its own independently.These indicate that the two bridges-carbonyl-and-imino-can block the tlanSmlSSion of the conjngative polarization of the whole system,so as to form three segments,this is verified by means of chemical synthesis and degradation.
文摘Rhodamine B-ethylenediamine-beta-cyclodextrins (RhB-beta-CDen) and rhodamine B-beta-cyclodextrins (RhB-beta-CD) form inclusion complexes with many vip molecules, which can be used as nucleic acid probe. In this paper we determined the most stable conformations of RhB-beta-CDen and RhB-beta-CD by molecular mechanics and dynamics simulation. The interaction between RhB-beta-CDen and two vip molecules, 1-borneol and cyclohexanol, have been investigated both theoretically and experimentally. The results show that the interaction between borneol and RhB-beta-CDen is stronger than that between cyclohexanol and RhB-beta-CDen.
文摘With the support of the Ministry of Science and Technology (MOST), scientists from the Chinese Academy of Atomic Energy and the Chinese Academy of Sciences (CAS) formally kicked off a new project to look into clean nuclear energy on September 27th in Beijing. The study, known as the accelerator-driven system of clean
文摘Second language acquisition can not be understood without addressing the interaction between language and cognition. Cognitive theory can extend to describe learning strategies as complex cognitive skills. Theoretical developments in Anderson’s production systems cover a broader range of behavior than other theories, including comprehension and production of oral and written texts as well as comprehension, problem solving, and verbal learning.Thus Anderson’s cognitive theory can be served as a rationale for learning strategy studies in second language acquisition.
文摘This paper discusses the stability structure and the bifurcation of phase path characteristics of synoptic scale system.The analytic results show that the catastrophe of the synoptic scale disturbance may be caused by the nonlinear effects of barotropic and baroclinic instability and advection of ambient large-scale flow.Also, foregoing nonlinear effects on the speed of development and decay of the system are presented in the processes deviating from or approaching to equilibrium state.It has been found that there is a resonance phenomenon between the time-oscillation of heat source and the atmospheric disturbance.
文摘Seven homologous series p-A=B-C_6H_4(CH=CH)_nX=Y (A=B: NO_2, X=Y: CHO, COMe, CN, NO_2; A=B: CN, X=Y: CHO, CN; A=B: H, X=Y: NO_2) were synthesized, the effect of opposite terminal groups in phenylpolyenic conjugative systems has been studied by means of UV, XPS, ^(13) C NMR and quantum chemical calculation. The results show that: 1. There exists the effect of opposite terminal groups exists in phenylpolyenic and other aromatic conjugative systems. 2. When A=B and X=Y are the same, the group (-X=Y) connected at polyenic chain is a terminal group, while the other is an opposite terminal group. When the two groups are different, the one with weaker conjugative power plays the role of the opposite terminal group. 3. The effect of opposite terminal groups increases successively in the order of CN, COMe, CHO, NO_2 and can be quantita- tively described with substitute equivalent △N_s. Theλ_(max) of compound containing an opposite terminal group can be calculated by the homologous equation 10^(-4) =a+b/(1/2)^(2/N＇^(-S)_a), most of the calculated values are in agreement with experiment results.
文摘Background A voluntary procedure for reporting adverse drug reactions (ADRs) was formally put in place in 1989. However,only a small proportion of ADR reports are actually forwarded to the national monitoring center. To identify the reasons for underreporting,the authors investigated the awareness and attitudes of healthcare professionals (doctors,nurses,and administrators) toward the ADR system in China. In addition,the authors sought to formulate approaches to improve the current ADR reporting system.Methods Structured interviews were carried out in 16 hospitals selected from 27 municipal hospitals in Wuhan,Hubei Province,China. A questionnaire survey of a stratified random sample of approximately 15% of healthcare professionals in each selected hospital was conducted during February to March 2003.Results The response rate of this survey was 85%. One thousand six hundred and fifty-three questionnaires were used in the final analysis. Only 2.7% of the healthcare professionals had a correct understanding to the definition of ADR. Eighty-nine point two percent of the healthcare professionals had encountered ADRs. Ninety-four percent of them were aware of the need to report these to the ADR monitoring center. However,only 28.5% of doctors,22.8% of nurses,and 29.7% of administrators actually submitted a report. For the most part,they reported ADRs to the hospital pharmacy (66.0%),to other departments in the hospital (72.5%),and to the pharmaceutical industry (23.0%),rather than to the national monitoring center (2.9%) or regional monitoring center (9.5%). Severe or rare ADRs and ADRs to new products were generally perceived to be significant enough to report. Sixty-two point one percent of the healthcare professionals had encountered ADRs,yet not reported them to anybody. The major reasons for not reporting included no knowledge of the reporting procedure (71.4%),unavailability of the reporting center mailing address (67.9%),unavailability of the ADR report form (60.4%),lack of knowledge of the existence of a national ADR reporting system (52.2%),and belief that the ADR in question was already well known (44.1%). Conclusions Healthcare professionals in Wuhan,China have little basic knowledge of ADR and of the voluntary reporting system. The main reasons for underreporting were lack of basic knowledge about ADRs and the voluntary reporting procedure. Education and training of healthcare professionals is needed to improve the current ADR reporting system.
