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We evaluated the pollination syndromes of plant species occurring in revegetated patches of riparian Atlantic Forest in order to evaluate the success of restoration process. Between March 2013 and January 2014, the floral traits of all of the flowering plants found in, among four restoration sites of different ages and one reference site, were recorded and used to characterize pollination syndromes. Richness, abundance, and composition of pollination syndromes were related to season, age and width of the forest fragment, species richness and abundance of sampled plants, and also to the quality of the surrounding matrix. There were differences in the composition of syndromes among sampling units and among seasons. Richness and abundance of pollination syndromes varied among climatic periods, the highest values occurred at the end of the dry season and the start of the rainy season. Older, wider, and areas with more plants had higher values of richness and abundance of syndromes. The quality of the surrounding matrix influences only the richness of syndromes. It was concluded that floral traits are good indicators of ecological restoration of riparian forests and that the surrounding matrix contributes to the greater richness of syndromes. However, when planning for active restoration, attention should be given to the proper choice of plant species on the basis of pollination syndromes that should attract pollinators. 相似文献
123.
Dhimitrius N. P. S. de Oliveira Pedro I. C. Claro Raquel R. de Freitas Maria A. Martins Tiago M. Souza Breno M. da S. e Silva Lourival M. Mendes Lina Bufalino 《化学与生物多样性》2019,16(9)
The açaí fruit depulping produces large amounts of long lignocellulosic fiber bundles that are disposed in the environment. Chemical pretreatments may improve açaí fibers favoring their usage in advanced materials. This work aimed to define optimal alkali reaction parameters to improve the properties of açaí fibers. Two NaOH concentrations (5 % and 10 %) and two reaction temperatures (80 °C and 100 °C) were tested. The raw and treated fibers were analyzed by scanning electron microscopy, Fourier transformed infrared spectroscopy, X‐ray diffraction, and thermal analyses. All the alkali pretreatments separated fibers from the bundles, unblocked pit channels by removing silicon structures, exposed the inner lignin, partially removed non‐cellulosic compounds, and raised the cellulose crystalline index. The highest temperature and NaOH content resulted in better cleaning and isolation of the fibers, while milder conditions better preserved the cellulose crystalline structure and thermal stability. 相似文献
124.
Ramos Patrícia A. B. Ferro Ana M. Oliveira M. Margarida Gonçalves Sónia Freire Carmen S. R. Silvestre Armando J. D. Duarte Maria F. 《Phytochemistry Reviews》2019,18(2):495-526
Phytochemistry Reviews - Cynara cardunculus health benefits have aroused much interest, leading to the discovery of valuable bioactive compounds with a crucial role in plant defence. Guaianolides... 相似文献
125.
Ayslan Castro Brant Vladimir Majerciak Miguel Angelo Martins Moreira Zhi-Ming Zheng 《中国病毒学》2019,34(2):211-221
Human papillomavirus 18(HPV18) E6 and E7 oncogenes are transcribed as a single bicistronic E6 E7 pre-mRNA. The E6 ORF region in the bicistronic E6 E7 pre-mRNA contains an intron. Splicing of this intron disrupts the E6 ORF integrity and produces a spliced E6~*I RNA for efficient E7 translation. Here we report that the E6 intron has two overlapped branch point sequences(BPS) upstream of its 30 splice site, with an identical heptamer AACUA■C, for E6~*I splicing. One heptamer has a branch site adenosine(underlined) at nt 384 and the other at nt 388. E6~*I splicing efficiency correlates to the expression level of E6 and E7 proteins and depends on the selection of which branch site. In general, E6~*I splicing prefers the 30 ss-proximal branch site at nt 388 over the distal branch site at nt 384. Inactivation of the nt 388 branch site was found to activate a cryptic acceptor site at nt 636 for aberrant RNA splicing. Together, these data suggest that HPV18 modulates its production ratio of E6 and E7 proteins by alternative selection of the two mapped branch sites for the E6~*I splicing, which could be beneficial in its productive or oncogenic infection according to the host cell environment. 相似文献
126.
Filipa M. S. Martins Mafalda Galhardo Ana F. Filipe Amílcar Teixeira Paulo Pinheiro Joana Pauprio Paulo C. Alves Pedro Beja 《Molecular ecology resources》2019,19(4):863-876
DNA metabarcoding can contribute to improving cost‐effectiveness and accuracy of biological assessments of aquatic ecosystems, but significant optimization and standardization efforts are still required to mainstream its application into biomonitoring programmes. In assessments based on freshwater macroinvertebrates, a key challenge is that DNA is often extracted from cleaned, sorted and homogenized bulk samples, which is time‐consuming and may be incompatible with sample preservation requirements of regulatory agencies. Here, we optimize and evaluate metabarcoding procedures based on DNA recovered from 96% ethanol used to preserve field samples and thus including potential PCR inhibitors and nontarget organisms. We sampled macroinvertebrates at five sites and subsampled the preservative ethanol at 1 to 14 days thereafter. DNA was extracted using column‐based enzymatic (TISSUE) or mechanic (SOIL) protocols, or with a new magnetic‐based enzymatic protocol (BEAD), and a 313‐bp COI fragment was amplified. Metabarcoding detected at least 200 macroinvertebrate taxa, including most taxa detected through morphology and for which there was a reference barcode. Better results were obtained with BEAD than SOIL or TISSUE, and with subsamples taken 7–14 than 1–7 days after sampling, in terms of DNA concentration and integrity, taxa diversity and matching between metabarcoding and morphology. Most variation in community composition was explained by differences among sites, with small but significant contributions of subsampling day and extraction method, and negligible contributions of extraction and PCR replication. Our methods enhance reliability of preservative ethanol as a potential source of DNA for macroinvertebrate metabarcoding, with a strong potential application in freshwater biomonitoring. 相似文献
127.
128.
Gustavo Benevides Martins Giacomo Giacomelli Oliver Goldbeck Gerd M. Seibold Marc Bramkamp 《Molecular microbiology》2019,111(5):1335-1354
Many bacteria take up carbohydrates by membrane‐integral sugar specific phosphoenolpyruvate‐dependent carbohydrate:phosphotransferase systems (PTS). Although the PTS is centrally involved in regulation of carbon metabolism in different bacteria, little is known about localization and putative oligomerization of the permease subunits (EII). Here, we analyzed localization of the fructose specific PtsF and the glucose specific PtsG transporters, as well as the general components EI and HPr from Corynebacterium glutamicum using widefield and single molecule localization microscopy. PtsF and PtsG form membrane embedded clusters that localize in a punctate pattern. Size, number and fluorescence of the membrane clusters change upon presence or absence of the transported substrate, and a direct influence of EI and HPr was not observed. In presence of the transport substrate, EII clusters significantly increased in size. Photo‐activated localization microscopy data revealed that, in presence of different carbon sources, the number of EII proteins per cluster remains the same, however, the density of these clusters reduces. Our work reveals a simple mechanism for efficient membrane occupancy regulation. Clusters of PTS EII transporters are densely packed in absence of a suitable substrate. In presence of a transported substrate, the EII proteins in individual clusters occupy larger membrane areas. 相似文献
129.
Martins Nicole Magalhães Rui Castro Carolina Couto Ana Díaz-Rosales Patrícia Oliva-Teles Aires Peres Helena 《Amino acids》2019,51(9):1307-1321
Amino Acids - This study aimed to evaluate the effect of taurine (tau) supplementation to low fishmeal (FM) diets on growth performance, oxidative status, and immune response of European seabass... 相似文献
130.
Sez‐Jade Chen Nattawut Sinsuebphon Alena Rudkouskaya Margarida Barroso Xavier Intes Xavier Michalet 《Journal of biophotonics》2019,12(3)
We introduce a simple new approach for time‐resolved multiplexed analysis of complex systems using near‐infrared (NIR) dyes, applicable to in vitro and in vivo studies. We show that fast and precise in vitro quantification of NIR fluorophores' short (subnanosecond) lifetime and stoichiometry can be done using phasor analysis, a computationally efficient and user‐friendly representation of complex fluorescence intensity decays obtained with pulsed laser excitation and time‐gated camera imaging. We apply this approach to the study of binding equilibria by Förster resonant energy transfer using two different model systems: primary/secondary antibody binding in vitro and ligand/receptor binding in cell cultures. We then extend it to dynamic imaging of the pharmacokinetics of transferrin engagement with the transferrin receptor in live mice, elucidating the kinetics of differential transferrin accumulation in specific organs, straightforwardly differentiating specific from nonspecific binding. Our method, implemented in a freely‐available software, has the advantage of time‐resolved NIR imaging, including better tissue penetration and background‐free imaging, but simplifies and considerably speeds up data processing and interpretation, while remaining quantitative. These advances make this method attractive and of broad applicability for in vitro and in vivo molecular imaging and could be extended to applications as diverse as image‐guided surgery or optical tomography. 相似文献