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101.
Mark Deakin Steve Curwell Patrizia Lombardi 《The International Journal of Life Cycle Assessment》2001,6(6):373-383
This paper has outlined the areas of the Environment and Climate Programme (Economic and Social Aspects of Human Settlement)
the BEQUEST project addresses. It has also examined the framework for analysis the project sets out for a common understanding
of SUD and the assessment methods currently made use of by planners, architects, engineers and surveyors to build environmental
capacity. The paper has done this by:
相似文献
• | fore-grounding the question of urban development and representing the process of urbanisation as a life cycle of inter-related activities; |
• | agreeing the sustainable development issues underlying the urban process; |
• | identifying the environmental, economic and social structure, spatial level and time scales of sustainable urban development. |
102.
Bollworm responses to release of genetically modified Helicoverpa armigera nucleopolyhedroviruses in cotton 总被引:6,自引:0,他引:6
Sun X Chen X Zhang Z Wang H Bianchi FJ Peng H Vlak JM Hu Z 《Journal of invertebrate pathology》2002,81(2):63-69
Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus (HaSNPV) has been developed as a commercial biopesticide to control the cotton bollworm, H. armigera, in China. The major limitation to a broader application of this virus has been the relative long time to incapacitate the target insect. Two HaSNPV recombinants with improved insecticidal properties were released in bollworm-infested cotton. One recombinant (HaCXW1) lacked the ecdysteroid UDP-glucosyltransferase (egt) gene and in another recombinant (HaCXW2), an insect-selective scorpion toxin (AaIT) gene replaced the egt gene. In a cotton field situation H. armigera larvae treated with either HaCXW1 or HaCXW2 were killed faster than larvae in HaSNPV-wt treated plots. Second instar H. armigera larvae, which were collected from HaCXW1 and HaCXW2 treated plots and further reared on artificial diet, showed reduced ST(50) values of 15.3 and 26.3%, respectively, as compared to larvae collected from HaSNPV-wt treated plots. The reduction in consumed leaf area of field collected larvae infected with HaCXW1 and HaCXW2 was approximated 50 and 63%, respectively, as compared to HaSNPV-wt infected larvae at 108 h after treatment. These results suggest that in a cotton field situation the recombinants will be more effective control agents of the cotton bollworm than wild-type HaSNPV. 相似文献
103.
The available quantity of archaeobotanical data derived from the identification of macroremains has expanded considerably
over the last few decades. In order to obtain a supraregional or even regional overview for a particular period of time, or
of the distribution of a single species, a database is needed. At the Archaeobotanical Department of the Institute of the
"Kommission für Arch?ologische Landesforschung in Hessen e.V." (KAL) such a database has been developed in the last few years.
It is suitable for the handling of large quantities of archaeobotanical results, including a whole range of background information
comprising archaeological, ecological and other related data, and offers various possibilities for the evaluation of these
data.
Received January 8, 2001 / Accepted April 9, 2002 相似文献
104.
We develop a protocol for estimating the free energy difference between different conformations of the same polypeptide chain. The conformational free energy evaluation combines the CHARMM force field with a continuum treatment of the solvent. In almost all cases studied, experimentally determined structures are predicted to be more stable than misfolded "decoys." This is due in part to the fact that the Coulomb energy of the native protein is consistently lower than that of the decoys. The solvation free energy generally favors the decoys, although the total electrostatic free energy (sum of Coulomb and solvation terms) favors the native structure. The behavior of the solvation free energy is somewhat counterintuitive and, surprisingly, is not correlated with differences in the burial of polar area between native structures and decoys. Rather. the effect is due to a more favorable charge distribution in the native protein, which, as is discussed, will tend to decrease its interaction with the solvent. Our results thus suggest, in keeping with a number of recent studies, that electrostatic interactions may play an important role in determining the native topology of a folded protein. On this basis, a simplified scoring function is derived that combines a Coulomb term with a hydrophobic contact term. This function performs as well as the more complete free energy evaluation in distinguishing the native structure from misfolded decoys. Its computational efficiency suggests that it can be used in protein structure prediction applications, and that it provides a physically well-defined alternative to statistically derived scoring functions. 相似文献
105.
F. J. Stadelmann B. Boller G. Spangenberg R. Kölliker Z. Y. Wang I. Potrykus J. Nösberger 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(5):634-639
Two sets of plants (Lb and Lc), regenerated from different single-genotype-derived embryogenic suspension cultures of Lolium perenne cv Citadel, were evaluated for agronomic traits in a modified polycross design in the field. Seed from the primary regenerated
plants was harvested to evaluate morphological and phenological traits of corresponding progenies in a replicated field experiment.
When compared to seed-grown plants of the same cultivar, primary regenerants of the Lb set showed a significant delay in ear emergence and a more-erect growth habit, while primary regenerants from the Lc set showed a significantly higher seed yield. However, progenies of regenerated plants did not differ from those of seed-grown
plants. Embryogenic suspension cells of L. perenne have the potential for producing fertile, well-performing, material which can be integrated into breeding programs.
Received: 3 November 1997 / Accepted: 25 November 1997 相似文献
106.
湖南茶叶植物资源的评价 总被引:3,自引:0,他引:3
对城步峒茶、江华苦茶、汝城白毛茶和云台山种等湖南茶叶植物资源的主要化学成分、光合特性和生产性状进行了研究。结果表明,茶多酚与儿茶素含量从高到低依次为汝城白毛茶、江华苦茶、城步峒茶、云台山种;各资源的游离氨基酸、茶氨酸和咖啡碱含量均为正常水平;汝城白毛茶属高茶多酚资源,它所含生物碱的组成方式与毛叶茶龙门模式种不同,虽可可碱和茶叶碱含量比茶种高,但仍以咖啡碱为主。在阴天阴凉条件下的净光合速率为汝城白毛茶>城步峒茶>江华苦茶>云台山种,净光合速率与光量子通量、叶面温度呈极显著正相关,与气孔阻力呈极显著负相关,相关系数分别为09278、09115和-08937。在晴天高温度强光条件下,净光合速率为云台山种>城步峒茶>江华苦茶>汝城白毛花,净光合速率与光量子通量、叶面温度和气孔阻力都呈极显著负相关,相关系数分别为-09165、-09328、-09031。在主要生产性状中,汝城白毛茶能安全通过-6℃的低温,在高茶多酚资源中,抗寒性突出,是选育红茶良种的一个非常有益的关键性状。 相似文献
107.
森林旅游资源评价中的空气负离子研究 总被引:73,自引:2,他引:71
空气负离子被喻为空气维生素或生长素,对人体健康有利。自英国学者威尔逊与法国学者埃尔斯特和格特尔证实空气负离子的存在,人们对空气负离子的研究经历了近百年的发展、应用阶段1)。在我国,解放区战地医院曾采用了空气雾疗法,50年代有关文献中出现了空气负离子的... 相似文献
108.
化工废水生态毒性原因鉴别的实例研究 总被引:2,自引:0,他引:2
以南京市某一化工厂排出的废水为对象,对其生态毒性原因作了鉴别研究.结果表明,废水对Daphniamagna具有急性毒性,C18固相提取可去除废水毒性,存在的主要毒物为非极性有机化合物.废水经C18固相提取,发现废水中的主要可疑毒物为苯并吡喃酮和苯酚,是导致废水毒性的关键污染物,对废水毒性的贡献率分别为44.6%和32.9%. 相似文献
109.
用硅藻群集指数(DAIpo)和河流污染指数(RPId)评价珠江广州河段的水质状况 总被引:5,自引:0,他引:5
用硅藻计于1990年采集珠江广州河段的9个采样点的附着硅藻群落.共得硅藻24个属,170个分类单位,其中,适腐性种8个,广腐性种84个,仍腐性种78个.群落相似性聚类分析表明,位于前、后航道中部的员村(st3),新造(st8),沙浴村(si10)三点的硅藻群落结构是为相似,向上,下游相似性逐渐减小.用硅藻群集指数(DAIpo)和河流污染指数(RPId)对各采样断面的水质进行分析表明:大盛(st12)和莲花山(st5)两点受污染最轻,属β-寡污带,黄沙点(st2)污染最严重,属α-中污带.对照点鸦岗(St1)也受到一定的污染,属α-寡污带,其它点的污染程度在α-寡污带与β-中污带之间.DAIpo值与BODS存在着显著的负相关(r=0.86).珠江广州河段的前、后航道的污染程度相差不大(RPId=56.42,56.26),均属中度污染. 相似文献
110.
J.A. Narciso 《Letters in applied microbiology》2009,48(5):548-553
Aims: It is often difficult to extrapolate information from a Petri dish and apply it to commercial applications as with antimicrobial assays. Often large volumes of commodities are used for a virtually untested protocol and result in an unnecessary expenditure of time and materials. An intermediate method, where experimental compounds could be tested directly on a specific commodity without expending large quantities of either sample or compound, would be practical and economical.
Methods and Results: A method was developed that employs the use of a small experimental chamber in which pieces of natural materials (e.g. fruit) can be tested with antimicrobial compounds. This method uses a type of autoclavable incubation chamber with a filter paper base, hydrating sponge pieces and a sterile glass sample platform. The chamber offers a sterile, controlled environment and can be manipulated to serve a number of studies.
Conclusion: The chamber results are more analogous to what happens on whole fruit than the Petri dish.
Significance and Impact of the Study: This method is presently used to screen for antimicrobial compounds and treatments needed to control serious economic pests compromising Florida's agriculture. 相似文献
Methods and Results: A method was developed that employs the use of a small experimental chamber in which pieces of natural materials (e.g. fruit) can be tested with antimicrobial compounds. This method uses a type of autoclavable incubation chamber with a filter paper base, hydrating sponge pieces and a sterile glass sample platform. The chamber offers a sterile, controlled environment and can be manipulated to serve a number of studies.
Conclusion: The chamber results are more analogous to what happens on whole fruit than the Petri dish.
Significance and Impact of the Study: This method is presently used to screen for antimicrobial compounds and treatments needed to control serious economic pests compromising Florida's agriculture. 相似文献