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601.
This Commentary describes a call for submissions for the upcoming Special Issue focused on the science presented at the 20th IUPAB Congress to be held in conjunction with the 45th Annual Meeting of the Brazilian Biophysical Society and the 49th Annual Meeting of the Brazilian Society for Biochemistry and Molecular Biology.

Due to the COVID-19 pandemic, the 20th International IUPAB Congress will take place as a virtual meeting this year from October 4 to 8, 2021. This triennial IUPAB Congress will be held in loose conjunction with the 45th Annual Meeting of the Brazilian Biophysical Society and the 49th Annual Meeting of the Brazilian Society for Biochemistry and Molecular Biology. To act as a complement to this virtual meeting, the Biophysical Reviews journal will base a Special Issue on the scientific topics of the meeting contributors selected from the range of invited speakers and poster presenters. This Special Issue will also work to highlight the host country’s (Brazil) National Biophysical Society. Finally, this Special Issue will also serve to publish the meeting abstracts in supplemental form.Review articles from IUPAB Congress speakers and poster presenters to the IUPAB Congress and associated conferences (the 45th Annual Meeting of the Brazilian Biophysical Society and the 49th Annual Meeting of the Brazilian Society for Biochemistry and Molecular Biology) are solicited. Similar to the SI based on the 19th IUPAB Congress held in Edinburgh summarizing Commentaries from session chairs are also requested (Hall and dos Remedios 2017). The Special Issue for the 20th IUPAB International Congress will be prepared and edited by the current authors (Rosangela Itri, Mauricio Baptista, Richard Garratt, and Antonio Jose Costa-Filho).  相似文献   
602.
Benthic macroinvertebrate assemblages, water chemistry variables and environmental degradation were investigated in an Atlantic Forest region in Brazil. Seven sites of the Guapimirim river basin were studied during three sampling periods based on the rain regime: end of wet season (May 1998), dry season (August 1998), and wet season (January 1999). Four substrates were collected at each site: sand, stony substrates, litter in pool areas and litter in riffle areas. Relationships between macroinvertebrate assemblages, water chemistry variables and environmental degradation were examined using canonical correspondence analysis (CCA). According to CCA, concentrations of dissolved oxygen and chloride, and the environmental degradation, measured by the Riparian Channel Environment index, exhibited the strongest relationship to macroinvertebrate assemblages. Overall, the loss of community diversity measured by the Shannon Index along the degradation gradient was observed. Some taxa were shown to be sensitive to water pollution, especially among Plecoptera, Trichoptera, Coleoptera and some Ephemeroptera, while others such as Simuliidae, Odonata and molluscs were tolerant to moderate levels of pollutants. The Chironomidae were the only group tolerant to a high level of pollutants and degradation.  相似文献   
603.
604.
Recombinant DNA clones have been isolated that contain 80 kb of the beta-globin complex from the deer mouse, Peromyscus maniculatus. Comparisons of this complex with that from the laboratory mouse, Mus domesticus (with an order 5'-Hbby, Hbb-bhO, Hbb-bhl, Hbb-bh2, Hbb-bh3, Hbb-bl, Hbb-b2 3') highlight organizational trends in the beta-globin complex since the two species diverged. Unlike other mammals studied thus far, the deer mouse possesses three adult genes. Partial sequence analysis indicates that each of the three adult genes is intact and hence may be functional. Hybridization of one of the two Mus pseudogenes, Hbb-bh3, to genomic blots from Peromyscus reveals that it has a homologous counterpart in Peromyscus. Homologous genes to the two gamma-like Mus genes, Hbb-bhO and Hbb-bhl, are also found in Peromyscus. The strong hybridization between the Hbb-bhl genes and significant nucleotide similarity between the Hbb-bhO genes suggest that both pairs are important for the ontogeny of these mice although no known product has been identified for the Hbb-bhO genes. The presence of Hbb-bhO and Hbb-bhl in Peromyscus suggests that the duplication that created this related gene set occurred before the two lineages diverged. A single gene for Hbb-y has been isolated from Peromyscus. The adult region in Peromyscus has undergone significant divergence from the same region in Mus, having three rather than two adult genes, the acquisition of at least 15 kb of extra DNA relative to Mus, and possibly the loss of the Hbb-bh2 pseudogene. The nonadult region of the complex, in contrast, contains the same set of genes apparently distributed over the same amount of DNA as in the Mus beta- globin complex. This observation suggests that the embryonic region of the complex is more evolutionarily stable than the adult region.   相似文献   
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