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Roberto Pilu Andrea Bucci Laura Casella Chiara Lago Francesco Cerino Badone Elena Cassani Michela Landoni 《Molecular breeding : new strategies in plant improvement》2012,30(2):799-807
We produced and studied for 3?years two synthetic populations of maize differing in their constitution only for the selected alleles present at the red color 1 (r1) locus (R-sc vs. r?Cr). r1 is a regulatory gene conferring anthocyanin pigmentation in different tissues: the R-sc allele confers pigmentation only in the aleurone seed layer, while the r?Cr allele confers pigmentation in several tissues such as root, silk and anther but the seed is colourless. The colourless population (r?Cr/r?Cr) was characterized by improved agronomic features, such as ear weight and plant height, compared with the R-sc/R-sc coloured population. This finding was confirmed by studying single F4 R/r families where the presence of the r?Cr allele conferred positive features, acting as a dominant trait. Quantitative trait locus (QTL) analysis performed using molecular markers on the long arm of chromosome 10 (bin 10.06), where the r1 gene maps, identified a QTL map position for plant height tightly associated to the r1 gene. Thus the r1 gene may represent a major QTL or it could be closely linked to another gene involved in the agronomic performance of the two populations studied. 相似文献
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Gentile Francesco Ficetola 《Biodiversity and Conservation》2013,22(12):2983-2988
Recent analyses of internet search volume hypothesized a decline of public interest toward themes related to environment, biodiversity conservation and fishery. These analyses were based on Google Trends, which is a measure of how frequently a term is searched in Google, in proportion to the total of searches performed. Google Trends is a measure of relative search, and this may make difficult assessing temporal trends. I evaluated whether relative declines in internet search volumes represent genuine decline in interest toward environmental-related themes, by comparing trends of terms representing various themes, including environment, computer science, other disciplines (astrophysics) and leisure. Similar values of relative decline were detected for environmental terms, for computer science terms, and for other scientific disciplines. Conversely, an increase was observed for leisure related terms. This suggests that interest toward the environment is not truly decreasing. The apparent decline of environmental and scientific terms is most likely caused by the increasing use of internet for aims unrelated to science and technology, such as leisure. Internet search tools are a powerful source of information, but users should be aware of the complexity of analysing their data: using unrelated terms as benchmark may help to identify genuine trends. 相似文献
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Franco Chimenti Daniela Secci Adriana Bolasco Paola Chimenti Arianna Granese Simone Carradori Elias Maccioni M. Cristina Cardia Matilde Yáñez Francisco Orallo Stefano Alcaro Francesco Ortuso Roberto Cirilli Rosella Ferretti Simona Distinto Johannes Kirchmair Thierry Langer 《Bioorganic & medicinal chemistry》2010,18(14):5063-5070
The present study reports on synthesis in high yields (70–99%), HPLC enantioseparation, inhibitory activity against human monoamino oxidases, and molecular modeling including 3D-QSAR studies, of a large series of (4-aryl-thiazol-2-yl)hydrazones (1–45). Most of the synthesized compounds proved to be potent and selective inhibitors of hMAO-B isoform in the micromolar or nanomolar range, thus demonstrating that hydrazothiazole could be considered a good pharmacophore to design new hMAO-B inhibitors. Due to the presence in some derivatives of a chiral center, we also performed a semipreparative chromatographic enantioseparation of these compounds obtained by a stereoconservative pattern. The separated enantiomers were submitted to in vitro biological evaluation to point out the stereorecognition of the active site of the enzyme towards these structures. Finally, a 3D-QSAR study was carried out using Comparative Molecular Field Analysis (CoMFA), aiming to deduce rational guidelines for the further structural modification of these lead compounds. 相似文献
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Marsano RM Milano R Minervini C Moschetti R Caggese C Barsanti P Caizzi R 《Genetica》2003,117(2-3):281-289
The molecular organization of the heterochromatic h39 region of the Drosophila melanogaster second chromosome has been investigated by studying two BAC clones identified both by Southern blotting and by FISH experiments as containing tandem arrays of Bari1, a transposable element present only in this region. Such BAC clones appear to contain different portions of the h39 region since they differ in the DNA sequences flanking the Bari1 repeats on both sides. Thus, the 80 Bari1 copies estimated to be present in the h39 region are split into at least two separated subregions. On the basis of the analysis of the flanking sequences a possible mechanism depending on an aberrant activity of the Bari1 transposase is proposed for the genesis of the heterochromatic tandem arrays of the element. 相似文献
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John Gallagher Biswajit Basu Maria Browne Alan Kenna Sarah McCormack Francesco Pilla David Styles 《Journal of Industrial Ecology》2019,23(1):133-140
Renewable energy (RE) technologies are looked upon favorably to provide for future energy demands and reduce greenhouse gas (GHG) emissions. However, the installation of these technologies requires large quantities of finite material resources. We apply life cycle assessment to 100 years of electricity generation from three stand‐alone RE technologies—solar photovoltaics, run‐of‐river hydro, and wind—to evaluate environmental burden profiles against baseline electricity generation from fossil fuels. We then devised scenarios to incorporate circular economy (CE) improvements targeting hotspots in systems’ life cycle, specifically (1) improved recycling rates for raw materials and (ii) the application of eco‐design. Hydro presented the lowest environmental burdens per kilowatt‐hour of electricity generation compared with other RE technologies, owing to its higher efficiency and longer life spans for main components. Distinct results were observed in the environmental performance of each system based on the consideration of improved recycling rates and eco‐design. CE measures produced similar modest savings in already low GHG emissions burdens for each technology, while eco‐design specifically had the potential to provide significant savings in abiotic resource depletion. Further research to explore the full potential of CE measures for RE technologies will curtail the resource intensity of RE technologies required to mitigate climate change. 相似文献
38.
We consider the potential role of oscillations in the prefrontal cortex (PFC) in mediating attention, working memory and memory consolidation. Activity in the theta, beta, and gamma bands is related to communication between PFC and different brain areas. While gamma/beta oscillations mediate bottom-up and top-down interactions between PFC and visual cortices, related to attention, theta rhythms are engaged by hippocampal/PFC interplay. These interactions are dynamic, depending on the nature and relevance of the information currently being processed. The profound modifications of the PFC neuronal network associated with changes in oscillatory coherence are controlled by neuromodulators such as dopamine, which thereby allow or prevent the formation of cell assemblies for information encoding and storage. 相似文献
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Lesley A. Mathews Francesco Crea W.L. Farrar 《Differentiation; research in biological diversity》2009
Through the classic study of genetics, much has been learned about the regulation and progression of human disease. Specifically, cancer has been defined as a disease driven by genetic alterations, including mutations in tumor-suppressor genes and oncogenes, as well as chromosomal abnormalities. However, the study of normal human development has identified that in addition to classical genetics, regulation of gene expression is also modified by ‘epigenetic’ alterations including chromatin remodeling and histone variants, DNA methylation, the regulation of polycomb group proteins, and the epigenetic function of non-coding RNA. These changes are modifications inherited during both meiosis and mitosis, yet they do not result in alterations of the actual DNA sequence. A number of biological questions are directly influenced by epigenetics, such as how does a cell know when to divide, differentiate or remain quiescent, and more importantly, what happens when these pathways become altered? Do these alterations lead to the development and/or progression of cancer? This review will focus on summarizing the limited current literature involving epigenetic alterations in the context of human cancer stems cells (CSCs). The extent to which epigenetic changes define cell fate, identity, and phenotype are still under intense investigation, and many questions remain largely unanswered. Before discussing epigenetic gene silencing in CSCs, the different classifications of stem cells and their properties will be introduced. This will be followed by an introduction to the different epigenetic mechanisms. Finally, there will be a discussion of the current knowledge of epigenetic modifications in stem cells, specifically what is known from rodent systems and established cancer cell lines, and how they are leading us to understand human stem cells. 相似文献
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