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81.
In order to evaluate the impact of green technology innovation on ecological-economic efficiency of strategic emerging industries, the evaluation model is developed by the entropy weighted TOPSIS method. Through analyzing the impact factors of green technology innovation, the evaluation indicators system is constructed including positive factors and obstacles factors. The evaluation process is proposed, and six kinds of industry are selected to be the research objects on which the empirical analysis is made, the results show that the highest is the home audio-visual equipment manufacturers S6(E) whose weight is 0.7940 and the lowest is the electronic computer manufacturers S2(E) whose weight is 0.1938, finally, the countermeasures are proposed. The findings can avoid the subjectivity of human factors on the empowerment and solve the limitations of sample size and data distribution, and can help researchers precisely find the deficiency based on evaluation results.  相似文献   
82.
Industrial symbiosis (IS) has been identified as a strategy for promoting industrial sustainability. IS has been defined as the development of close working agreements between industrial and other organizations that, through the innovative reuse, recycling, or sharing of resources, leads to resource efficiency. Key to IS are innovation and social network development. This article critically reviews IS literature and concludes that, to inform proactive strategies for promoting IS, the understanding of the social processes leading to resource innovation needs to be improved. Industrial ecologists generally believe that close geographical proximity and trust are essential to the development of IS. This article argues, however, that there is a need to learn more about the meaning of, need for, and specific role of geographical proximity and trust in IS and, additionally, that other potentially important social factors have remained underexplored. To move IS research forward, this article suggests to engage with research in economic geography on the concept of ‘proximity,’ which draws attention to the ways in which geographical, cognitive, institutional, social, and organizational distances between actors might affect innovation. Arguably, the analytically distinct, but flexible, dimensions of proximity can be useful to explore how and why IS develops. The resulting qualitative knowledge would form a basis for researching whether general patterns for IS development exist and, more important, could inform public and private strategies that indicate which actions could be taken, as well as when and in what way to promote resource synergies and sustainable industrial development.  相似文献   
83.
"基因工程"教学改革初探   总被引:13,自引:1,他引:12  
基因工程课程必须适应当今教育要求,以培养学生创新精神和实践能力为核心,以开发、利用和整合多种教学资源为手段,重点培养学生综合素质和能力.因此,总结基因工程课程建设中在课程总体规划的设置、多媒体辅助教学手段的运用、理论和实验教学相结合、现代教学模式的应用等方面所进行一些探索,以期提高基因工程教学效果和质量.  相似文献   
84.
对食品微生物学实验教学中的基础性实验、综合应用性实验、设计性实验等各层次的教学内容、教学手段、考核方式等进行改革和探索,创建适合培养广东海洋大学食品科学与工程、食品质量与安全专业学生的食品微生物学实验教学体系,对实验教学中遇到的难题提出了解决方法和思路,对提高学生动手能力,培养学生创新能力提供一些举措和思路。  相似文献   
85.
The evolutionary history of vascular plants is reviewed by extrapolation back through time from a wide range of data recently derived from the present flora, using as the central theme evolutionary inferences gained from phylogenies reconstructed as cladograms. Any region of the genome can be used to infer relationships, but only a combination of knowledge of morphology and the developmental genes that underpin morphology can allow evolutionary interpretation of macroevolutionary transitions; this in turn is necessary to identify bona fide evolutionary radiations and any putative causal key innovations. Such studies require clades to be delimited not by the inclusion of particular extant ‘crown’ species but rather by specific apo‐morphies, thereby giving important phylogenetic roles to extinct as well as extant species. Dating phylogenetic divergences via molecular clocks remains seriously inaccurate, and ultimately relies primarily on fossil benchmarks. First principles suggest that evolution of most regions of the genome is fundamentally gradual, whereas evolution of regions especially prone to strong selection pressure, and of the many facets of the phenotype, is punctuational, being characterized through time dominantly by stasis. Sequence data have proved valuable for inferring monophyletic groups, but within the now widely accepted context of monophyly the taxonomic hierarchy should primarily reflect degrees of morphological rather than molecular divergence. Incongruence among contrasting data sets is best explained by understanding the biological constraints operating on each type of phylogenetic information. The conventional ‘uniformitarian’ view of evolution has only limited applicability as one traces the history of land plants through time. Diversity increased in stepwise fashion, reflecting either attainments of complexity and/or fitness thresholds by the lineage (intrinsic) or the availability of unusually permissive environments, often following major perturbations (extrinsic). The Quaternary period demonstrates especially well the resilience, and ease of migration, of the Earth's vegetation. A higher frequency of generation of novel phenotypes in the deep past is possible, but a far higher frequency of their establishment is certain; together, these factors generate an evolutionary pattern of nested radiations that is fractal, as saturation of the resource space rendered the environment decreasingly permissive through time. In the immediate future, evolutionary‐developmental genetics will have increasing value for testing homology, interpreting homoplasy and elucidating evolutionary constraints, and will become easier to pursue as whole‐genome sequences of additional ‘model’ species further invigorate comparative genomics. Complexity of gene regulation, both by other genes and by the cellular and extra‐cellular environment, appears a particularly fruitful area for further research. Nonetheless, environmental filtering of evolutionary novelties (whether instantaneously isolated mutant ‘prospecies’ or classic neoDarwinian ‘selfish genes’ selectively spreading through panmictic populations) can only be effectively understood by longer term monitoring of populations in the wild, to better capture rare evolutionary and ecological events and to better assess the efficacy of traditional microevolutionary processes. We believe that the resulting renaissance in macroevolutionary studies will encourage a broader systematic perspective ‐ one that better encompasses the remarkable diversity of evolutionary processes that together generated the present diversity of life.  相似文献   
86.
Internet interventions, and in particular Internet‐delivered cognitive behaviour therapy (ICBT), have existed for at least 20 years. Here we review the treatment approach and the evidence base, arguing that ICBT can be viewed as a vehicle for innovation. ICBT has been developed and tested for several psychiatric and somatic conditions, and direct comparative studies suggest that therapist‐guided ICBT is more effective than a waiting list for anxiety disorders and depression, and tends to be as effective as face‐to‐face CBT. Studies on the possible harmful effects of ICBT are also reviewed: a significant minority of people do experience negative effects, although rates of deterioration appear similar to those reported for face‐to‐face treatments and lower than for control conditions. We further review studies on change mechanisms and conclude that few, if any, consistent moderators and mediators of change have been identified. A recent trend to focus on knowledge acquisition is considered, and a discussion on the possibilities and hurdles of implementing ICBT is presented. The latter includes findings suggesting that attitudes toward ICBT may not be as positive as when using modern information technology as an adjunct to face‐to‐face therapy (i.e., blended treatment). Finally, we discuss future directions, including the role played by technology and machine learning, blended treatment, adaptation of treatment for minorities and non‐Western settings, other therapeutic approaches than ICBT (including Internet‐delivered psychodynamic and interpersonal psychotherapy as well as acceptance and commitment therapy), emerging regulations, and the importance of reporting failed trials.  相似文献   
87.
Local adaptation is a dynamic process by which different allele combinations are selected in different populations at different times, and whose genetic signature can be inferred by genome‐wide outlier analyses. We combined gene flow estimates with two methods of outlier detection, one of them independent of population coancestry (CIOA) and the other one not (ROA), to identify genetic variants favored when ecology promotes phenotypic convergence. We analyzed genotyping‐by‐sequencing data from five populations of a lizard distributed over an environmentally heterogeneous range that has been changing since the split of eastern and western lineages ca. 3 mya. Overall, western lizards inhabit forest habitat and are unstriped, whereas eastern ones inhabit shrublands and are striped. However, one population (Lerma) has unstriped phenotype despite its eastern ancestry. The analysis of 73,291 SNPs confirmed the east–west division and identified nonoverlapping sets of outliers (12 identified by ROA and 9 by CIOA). ROA revealed ancestral adaptive variation in the uncovered outliers that were subject to divergent selection and differently fixed for eastern and western populations at the extremes of the environmental gradient. Interestingly, such variation was maintained in Lerma, where we found high levels of heterozygosity for ROA outliers, whereas CIOA uncovered innovative variants that were selected only there. Overall, it seems that both the maintenance of ancestral variation and asymmetric migration have counterbalanced adaptive lineage splitting in our model species. This scenario, which is likely promoted by a changing and heterogeneous environment, could hamper ecological speciation of locally adapted populations despite strong genetic structure between lineages.  相似文献   
88.
The essential dialogue between Apollinian and Dionysiac poles required for the advance of music and art was likened to the scientific debate between «justifiers» and «innovators». The use of ratios and simple algorithms was indicted as being retrogressive in terms of modern microcomputer technology and iconometrographic models. Three examples were used to illustrate the approach in the resolution of complex data sets comparing samples: (1) 45,XO with a 46,XY controls, (2) sexual dimorphism in young adults and (3) Black and White Olympic athletes. The iconometrographic approach was proposed as a primary orientation in human biology, particularly in secular trend studies concerned with the recognition and assessment of complex evolutionary trends.  相似文献   
89.
Relatively, few species have been able to colonize extremely cold alpine environments. We investigate the role played by the cushion life form in the evolution of climatic niches in the plant genus Androsace s.l., which spreads across the mountain ranges of the Northern Hemisphere. Using robust methods that account for phylogenetic uncertainty, intraspecific variability of climatic requirements and different life-history evolution scenarios, we show that climatic niches of Androsace s.l. exhibit low phylogenetic signal and that they evolved relatively recently and punctually. Models of niche evolution fitted onto phylogenies show that the cushion life form has been a key innovation providing the opportunity to occupy extremely cold environments, thus contributing to rapid climatic niche diversification in the genus Androsace s.l. We then propose a plausible scenario for the adaptation of plants to alpine habitats.  相似文献   
90.
Genome sequencing has demonstrated that besides frequent small-scale duplications, large-scale duplication events such as whole genome duplications (WGDs) are found on many branches of the evolutionary tree of life. Especially in the plant lineage, there is evidence for recurrent WGDs, and the ancestor of all angiosperms was in fact most likely a polyploid species. The number of WGDs found in sequenced plant genomes allows us to investigate questions about the roles of WGDs that were hitherto impossible to address. An intriguing observation is that many plant WGDs seem associated with periods of increased environmental stress and/or fluctuations, a trend that is evident for both present-day polyploids and palaeopolyploids formed around the Cretaceous–Palaeogene (K–Pg) extinction at 66 Ma. Here, we revisit the WGDs in plants that mark the K–Pg boundary, and discuss some specific examples of biological innovations and/or diversifications that may be linked to these WGDs. We review evidence for the processes that could have contributed to increased polyploid establishment at the K–Pg boundary, and discuss the implications on subsequent plant evolution in the Cenozoic.  相似文献   
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