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991.
TCP Transcription Factors Predate the Emergence of Land Plants 总被引:4,自引:0,他引:4
992.
A pot-culture experiment was carried out to investigate the effect of arbuscular mycorrhizal (AM) fungus (Glomus macrocarpum Tul. and Tul.) on plant growth and Cd2+uptake by Apium graveolens L. in soil with different levels of Cd2+. Mycorrhizal (M) and non-mycorrhizal (NM) plants were grown in soil with 0, 5, 10, 40 and 80 Cd2+ mg kg−1soil. The infectivity of the fungus was not affected by the presence of Cd2+ in the soil. M plants showed better growth and less Cd2+ toxicity symptoms. Cd2+ root : shoot ratio was higher in M plants than in NM plants. These differences were more evident at highest Cd2+ level (80 mg kg−1 soil). Chlorophyll a and chlorophyll b concentrations were significantly higher in AM-inoculated celery leaves. The dilution effect due to increased biomass, immobilization
of Cd2+ in root and enhanced P-uptake in M plants may be related to attenuation of Cd2+toxicity in celery. 相似文献
993.
Lívia Santos Lima Karina Peres Gramacho José Luis Pires Didier Clement Uilson Vanderlei Lopes Nicolas Carels Abelmon da Silva Gesteira Fernanda Amato Gaiotto Júlio Cézar de Mattos Cascardo Fabienne Micheli 《Tree Genetics & Genomes》2010,6(5):663-676
In this study, we report results of the detection and analysis of SSR markers derived of cacao–Moniliophthora perniciosa expressed sequence tags (ESTs) in relation to cacao resistance to witches’ broom disease (WBD), and we compare the polymorphism
of those ESTs (EST-simple sequence repeat (SSR)) with classical neutral SSR markers. A total of 3,487 ESTs was used in this
investigation. SSRs were identified in 430 sequences: 277 from the resistant genotype TSH 1188 and 153 from the susceptible
one Catongo, totalizing 505 EST-SSRs with three types of motifs: dinucleotides (72.1%), trinucleotides (27.3%), and tetranucleotides
(0.6%). EST-SSRs were classified into 16 main categories; most of the EST-SSRs belonged to “Unknown function” and “No homology”
categories (45.82%). A high frequency of SSRs was found in the 5’UTR and in the ORF (about 27%) and a low frequency was observed
in the 3’UTR (about 8%). Forty-nine EST-SSR primers were designed and evaluated in 21 cacao accessions, 12 revealed polymorphism,
having 47 alleles in total, with an average of 3.92 alleles per locus. On the other hand, the 11 genomic SSR markers revealed
a total of 47 alleles, with an average of 5.22 alleles per locus. The association of EST-SSR with the genomic SSR enhanced
the analysis of genetic distance among the genotypes. Among the 12 polymorphic EST-SSR markers, two were mapped on the F2 Sca 6 × ICS 1 population reference for WBD resistance. 相似文献
994.
Hiroshi Nakayasu Katsuyoshi Mihara Ryo Sato 《Biochemical and biophysical research communications》1978,83(2):697-703
A membrane-bound aldehyde dehydrogenase was solubilized from rat liver microsomes and purified about 150-fold by chromatography on ω-aminohexyl- and 5′-AMP-Sepharose columns with a recovery of about 40%. The purified enzyme was homogeneous upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis and its monomeric molecular weight was estimated to be 51,000. In aqueous solution, it existed as large, polymeric aggregates. Its activity towards straight-chain aliphatic aldehydes increased as their carbon chain length was increased at least up to dodecanal, whereas aldehyde dehydrogenase in the cytosolic fraction of rat liver was most active with hexanal as substrate. 相似文献
995.
Qingbin Song Ye Wu Jinhui Li Zhishi Wang Danfeng Yu Huabo Duan 《The International Journal of Life Cycle Assessment》2018,23(10):1916-1927
Purpose
The rapid growth of vehicle sales and usage has highlighted the need for greenhouse gas (GHG) emission reduction in Macau, a special administrative region (SAR) of China. As the most primary vehicle type, light-duty vehicles (LDV, including light-duty gasoline vehicles (LDGVs) and light-duty diesel vehicles (LDDVs)) play a key role in promoting the GHG reduction and development of green transportation system in Macau.Methods
This study, on the basis of real-world tested and statistical data, firstly performed a streamlined life-cycle assessment (SLCA) on LDVs, to evaluate the potential GHG emissions and reduction through shifting to hybrid electric vehicles (HEVs) and electric vehicles (EVs).Results and discussion
The results show that the mean GHG emissions from the LDGVs, LDDVs, and HEVs per 100 km were 25.16, 20.30, and 15.00 kg CO2 eq, respectively. Under the current electricity mix in Macau, EVs with the emissions of 12.39 kg CO2 eq/100 km can achieve a significant GHG emission reduction of LDVs in Macau. The total GHG emissions from LDVs increased from 124.99 to 247.82 thousand metric tons over the periods 2001–2014, with a 5.42% annual growth rate. A scenario analysis indicated that the development of HEVs and EVs—especially EVs—has the potential to control the GHG emissions from LDVs. Under the electricity mix of natural gas (NG) and solar energy (SE), the GHG emissions from EVs would drop by about 22 and 28%, respectively, by 2030.Conclusions
This study develops a useful approach to evaluate the potential GHG emissions and its reduction strategies in Macau. All the obtained results could be useful for decision makers, providing robust support for drawing up an appropriate plan for improving green transportation systems in Macau.996.
Akihiko Mougi 《Evolutionary ecology》2016,30(3):365-377
Interspecific mutualisms are ubiquitous in nature, despite their ecological and evolutionary instability. Recent studies have developed coevolutionary theory of mutualisms, which coupled population and evolutionary dynamics, to resolve the longstanding puzzle. However, earlier studies assumed a time-scale separation between these dynamics, leaving an unanswered question of how a relaxation in the time-scale separation affects the coevolutionary dynamics of mutualism. Here I relax the strong assumption to theoretically show that ecological and evolutionary dynamics occurring in a similar time scale can stabilize an otherwise unstable mutualism. I show that the coevolutionary dynamics can cause a stable limit cycle or stable equilibrium in the population sizes, even if the population sizes increase unbounded in the absence of evolutionary adaptation. In contrast, coevolution can also cause stable limit cycle even if the population dynamics is stable in the absence of evolutionary adaptation. Furthermore, the model predicts that the population dynamics is likely to converge to equilibrium when the evolutionary speed of two species is similar and fast or highly dissimilar. The results suggest that the ease of the evolutionary ‘arms race’ is of crucial importance to maintain mutualism. 相似文献
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1000.
Nicholas De Genova 《Dialectical Anthropology》2016,40(2):125-141
Anthropology has conventionally taken as some of its most cherished foundational categories the precise opposites of the key concepts that animate this inquiry: rather than “bare life,” anthropology has tended always to emphasize the fullness and complexity of social and political life; instead of labor in the abstract, which we recognize in its commodified form as “labor-power,” anthropology has produced exquisite inventories of concrete laboring activities and the “cultural” content of productive work; against the impermanence and mutability of lives characterized by their mobility, the ethnographic enterprise has been deeply attached to the sedentarist presuppositions of lasting settlement, dwelling, and “community”; and contrary to the task of apprehending space on a global scale, ethnographic study has been overwhelmingly localized and place-bound. Rethinking these elementary premises of the ethnographic endeavor and situating these critical concepts at the center of our epistemological frameworks are crucial theoretical and practical tasks for any meaningful social inquiry today. In this regard, the Marxian theoretical arsenal is simply indispensable. But, in the derisive words of so many disciplinary forebears and overseers, is this properly “anthropological”? The prospective convergence of genuinely critical sociopolitical inquiry with the techniques and insights of anthropology must remain for us the locus of an urgent problem—an open question on an open horizon. 相似文献