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121.
A well‐used metaphor for oceanic islands is that they act as ‘natural laboratories’ for the study of evolution. But how can islands or archipelagos be considered analogues of laboratories for understanding the evolutionary process itself? It is not necessarily the case that just because two or more related species occur on an island or archipelago, somehow, this can help us understand more about their evolutionary history. But in some cases, it can. In this issue of Molecular Ecology, Garrick et al. ( 2014 ) use population‐level sampling within closely related taxa of Galapagos giant tortoises to reveal a complex demographic history of the species Chelonoidis becki – a species endemic to Isabela Island, and geographically restricted to Wolf Volcano. Using microsatellite genotyping and mitochondrial DNA sequencing, they provide a strong case for C. becki being derived from C. darwini from the neighbouring island of Santiago. But the interest here is that colonization did not happen only once. Garrick et al. ( 2014 ) reveal C. becki to be the product of a double colonization event, and their data reveal these two founding lineages to be now fusing back into one. Their results are compelling and add to a limited literature describing the evolutionary consequences of double colonization events. Here, we look at the broader implications of the findings of Garrick et al. ( 2014 ) and suggest genomic admixture among multiple founding populations may be a characteristic feature within insular taxa. 相似文献
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New metal complexes as potential therapeutics 总被引:5,自引:0,他引:5
The many activities of metal ions in biology have stimulated the development of metal-based therapeutics. Cisplatin, as one of the leading metal-based drugs, is widely used in treatment of cancer, being especially effective against genitourinary tumors such as testicular. Significant side effects and drug resistance, however, have limited its clinical applications. Biological carriers conjugated to cisplatin analogs have improved specificity for tumor tissue, thereby reducing side effects and drug resistance. Platinum complexes with distinctively different DNA binding modes from that of cisplatin also exhibit promising pharmacological properties. Ruthenium and gold complexes with antitumor activity have also evolved. Other metal-based chemotherapeutic compounds have been investigated for potential medicinal applications, including superoxide dismutase mimics and metal-based NO donors/scavengers. These compounds have the potential to modulate the biological properties of superoxide anion and nitric oxide. 相似文献
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Teijaro Christiana N. Adhikari Ajeeth Shen Ben 《Journal of industrial microbiology & biotechnology》2019,46(3-4):433-444
Journal of Industrial Microbiology & Biotechnology - Recent advances and emerging technologies for metabolic pathway engineering and synthetic biology have transformed the field of natural... 相似文献
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Tina Saupe Francesco Montinaro Cinzia Scaggion Nicola Carrara Toomas Kivisild Eugenia D’Atanasio Ruoyun Hui Anu Solnik Ophélie Lebrasseur Greger Larson Luca Alessandri Ilenia Arienzo Flavio De Angelis Mario Federico Rolfo Robin Skeates Letizia Silvestri Jessica Beckett Sahra Talamo Christiana L. Scheib 《Current biology : CB》2021,31(12):2576-2591.e12
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We study tools for checking the validity of a parametric regressionmodel. When the dimension of the regressors is large, many ofthe existing tests face the curse of dimensionality or requiresome ordering of the data. Our tests are based on the residualempirical process marked by proper functions of the regressors.They are able to detect local alternatives converging to thenull at parametric rates. Parametric and nonparametric alternativesare considered. In the latter case, through a proper principalcomponent decomposition, we are able to derive smooth directionaltests which are asymptotically distribution-free under the nullmodel. The new tests take into account precisely the geometryof the model. A simulation study is carried through andan application to a real dataset is illustrated. 相似文献