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71.
Seed of Stlosanthes humilis both have hard integuments and display physiological dormancy, the latter being lost during post-harvest ageing. Ethrel and l-aminocyclopropane-1-carboxylic acid (ACC) partially released scarified young seed from physiological dormancy. Cobalt and silver ions and abscisic acid inhibited germination of scarified non-dormant seed. Abscisic acid also inhibited germination of voung seed promoted by ACC. Thiourea and ethrel plus benzyladenine showed the greatest efficacy in breaking seed dormancy. 相似文献
72.
Clarissa Alves da Rosa Nelson Henrique de Almeida Curi Fernando Puertas Marcelo Passamani 《Biological invasions》2017,19(7):2101-2123
The invasion of alien species is an important cause of biodiversity loss worldwide, and many mammals are considered successful invaders outside their former range, with recognized detrimental effects to native ecosystems. Our aim was to review the current literature on alien mammals that have established feral populations in Brazil and to systematize the existing knowledge. Furthermore, we evaluated the current distributions of all invasion mammals and discuss different management actions, including eradication techniques for island populations. We found 17 species of alien mammals living in the wild in Brazil. Based on the current literature and databases regarding invasive species, Lepus europaeus and Sus scrofa had the largest distributions in the Brazilian territory and seem to continue expanding their geographic distributions. Feral dogs and cats were the main alien predators threatening wildlife conservation, especially in protected areas. Further, we call attention to the invasion of Bubalus bubalis, a large species that currently thrives in isolated populations but seems to be quickly expanding its distribution. In conclusion, alien mammals are widespread in Southern and Southeastern Brazil, but at least four ungulate species (Indian sambar, horse, goat, and axis deer) still have small and isolated populations. Finally, future efforts need to evaluate the impacts of alien mammals in Brazil and techniques for their control. 相似文献
73.
Christiane Noronha Fernandes-Brum Bruno de Oliveira Garcia Rafael Oliveira Moreira Solange Aparecida Ságio Horllys Gomes Barreto André Almeida Lima Natália Chagas Freitas Renato Ribeiro de Lima Carlos Henrique Siqueira de Carvalho Antonio Chalfun-Júnior 《Tree Genetics & Genomes》2017,13(6):131
The reliability of analyses using real-time quantitative polymerase chain reaction (RT-qPCR) depends on the selection of appropriate reference genes to correct for sample-to-sample and run-to-run variations. The aim of the present study was to select the most suitable reference genes for gene expression analyses in tissue samples from coffee, Coffea arabica L. (Arabica) grown under well-watered (WW) and water-deficit (WD) conditions and C. canephora Pierre ex A. Froehner (Robusta) grown under WW conditions. Expression profiles and stabilities were evaluated for 12 reference genes in different tissues from C. arabica and for 8 genes in tissues from C. canephora. The web-based RefFinder tool, which combines the geNorm, NormFinder, Bestkeeper, and Delta-Ct algorithms, was employed to assess the stability of the tested genes. The most stable reference genes identified for all tissues grouped (WW/WD) of C. arabica were clathrin adaptor protein medium subunit (AP47), ubiquitin (UBQ), 60S ribosomal protein L39 (RPL39), and elongation factor 1α (EF1α), while class III alcohol dehydrogenase (ADH2), β-actin (ACT), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), and ubiquitin (UBQ) genes were the most stable for all tissues grouped (WW) of C. canephora tissues. Validation by the expression level analysis of CaACO-like demonstrated that the use of the best and the worst set of reference genes produced different expression results. The results reinforce the general assumption that there is no universal reference gene and that it is essential to select the most appropriate gene for each individual experiment to apply adequate normalization procedures of RT-qPCR data. 相似文献
74.
Can current native tree seedling production and infrastructure meet an increasing forest restoration demand in Brazil? 下载免费PDF全文
Ana P. Moreira da Silva Daniella Schweizer Henrique Rodrigues Marques Ana M. Cordeiro Teixeira Thaiane V. M. Nascente dos Santos Regina H. R. Sambuichi Carolina G. Badari Ulysse Gaudare Pedro H. S. Brancalion 《Restoration Ecology》2017,25(4):509-515
Recent global commitments have placed forest and landscape restoration at the forefront of countries' efforts to recover ecosystem services, conserve biodiversity, and mitigate the effects of climate change. However, it needs to be asked if current native tree seedling supply meets an increase in demand for forest restoration? This study assessed the current configuration, distribution, and production capacity of forest nurseries producing native trees in Brazil. Brazil provides an interesting example of how global agreements aligned with national policies can lead to the proliferation of native seedling nurseries, and the challenges faced to restore species‐rich native forest ecosystems. We found that the nurseries in the Atlantic Forest region can still meet an increase in demand—both in terms of seedling quantity and diversity—because most of their production capacity is not currently used. However, not all Brazilian biomes have sufficient nurseries to meet restoration demands, thus there is a risk of using native species from a few biogeographical regions in a much spatially wider and ecologically diverse area. In addition, lack of seed supply and qualified labor can hamper the growth of the market. Barriers to seed supply may also lead to low levels of genetic variability and floristic representation in the populations and ecosystems to be restored. We conclude that restoration of high‐diversity forest ecosystems requires policies and supportive programs, with emphasis on private nurseries, to guarantee adequate supply of native tree seedlings and provide the necessary incentives to develop the emergent economy of forest restoration. 相似文献
75.
Acosta-Avalos D Dos Santos Azevedo LM Salama Andrade T Lins de Barros H 《European biophysics journal : EBJ》2012,41(5):405-413
Candidatus Magnetoglobus multicellularis (CMm) is a multicellular organism in which each constituent cell is a magnetotactic bacterium.
It has been observed that disaggregation of this organism provokes the death of the individual cells. The observed flagellar
movement of the CMm indicates that the constituent cells move in a coordinated way, indicating a strong correlation between
them and showing that this aggregate could be considered as an individual. As every constituent cell is a magnetotactic bacterium,
every cell contributes with a magnetic moment vector to the resultant magnetic moment of the CMm organism that can be calculated
through the vectorial sum of all the constituent magnetic moments. Scanning electron microscopy images of CMm organisms have
shown that the constituent cells are distributed on a helix convoluted on a spherical surface. To analyze the magnetic properties
of the distribution of magnetic moments on this curve, we calculated the magnetic energy numerically as well as the vectorial
sum of the magnetic moment distribution as a function of the number of cells, the sphere radius and the number of spiral loops.
This distribution proposes a magnetic organization not seen in any other living organism and shows that minimum energy configurations
of magnetic moments are in spherical meridian chains, perpendicular to the helix turns. We observed that CMm has a high theoretical
degree of magnetic optimization, showing that its geometrical structure is important to the magnetic response. Our results
indicate that the helical structure must have magnetic significance. 相似文献
76.
We compared the relative contribution of blackwater inundation forest (igapó) and unflooded (terra firme) forest for regional bird species diversity in the lower Rio Negro region. For analyses of habitat preference we used mist-net samples and an unpublished bird species check-list. The igapó forest had lower bird species diversity than the terra firme forest. However, some 14% of the forest bird species in the region are restricted to igapó forest. Species composition was found to be distinct between the understories of the two forest types. Common forest bird guilds in the Neotropics such as ant-following birds avoid igapó forest. The differential habitat selection among birds in the inundated and unflooded forest is likely to result from vegetation structure and biological interactions such as aggressive behaviour. Since the inundated forest has a typical biota, conservation efforts needs to be directed to protect these habitats. Unfortunately, inundation forests are threatened by several human actions, especially dam construction. The extent of protected areas in the Brazilian Amazon is insufficient for the adequate protection of the inundated habitats, because it includes only 3% of the total area. 相似文献
77.
Felipe Luiz Pereira Lucas Amorim Gonçalves Guilherme Campos Tavares Siomar de Castro Soares Fernanda Alves Dorella Alex Fiorini de Carvalho Márcia Pimenta Leibowitz Carlos Augusto Gomes Leal Vasco Ariston de Carvalho Azevedo Henrique César Pereira Figueiredo 《Genomics》2018,110(6)
Francisella noatunensis subsp. orientalis (FNO) is an important emerging pathogen associated with disease outbreaks in farm-raised Nile tilapia. FNO genetic diversity using PCR-based typing, no intra-species discrimination was achieved among isolates/strains from different countries, thus demonstrating a clonal behaviour pattern. In this study, we aimed to evaluate the population structure of FNO isolates by comparing whole-genome sequencing data. The analysis of recombination showed that Brazilian isolates group formed a clonal population; whereas other lineages are also supported by this analysis for isolates from foreign countries. The whole-genome multilocus sequence typing (wgMLST) analysis showed varying numbers of dissimilar alleles, suggesting that the Brazilian clonal population are in expansion. Each Brazilian isolate could be identified as a single node by high-resolution gene-by-gene approach, presenting slight genetic differences associated to mutational events. The common ancestry node suggests a single entry into the country before 2012, and the rapid dissemination of this infectious agent may be linked to market sales of infected fingerlings. 相似文献
78.
Marcos Vinicius Antunes de Lemos Elisa Peripolli Mariana Piatto Berton Fabiele Loise Braga Feitosa Bianca Ferreira Olivieri Nedenia Bonvino Stafuzza Rafael Lara Tonussi Sabrina Kluska Hermenegildo Lucas Justino Chiaia Lenise Mueller Adrielli Mathias Ferrinho Angelica Simone Cravo Prereira Henrique Nunes de Oliveira Lucia Galvão de Albuquerque Fernando Baldi 《Journal of applied genetics》2018,59(2):203-223
The aim of this study was to analyze the association between the copy number variation regions (CNVRs) and fatty acid profile phenotypes for saturated (SFA), monosaturated (MUFA), polyunsaturated (PUFA), ω6 and ω3 fatty acids, PUFA/SFA and ω6/ω3 ratios, as well as for their sums, in Nellore cattle (Bos primigenius indicus). A total of 963 males were finished in feedlot and slaughtered with approximately 2 years of age. Animals were genotyped with the BovineHD BeadChip (Illumina Inc., San Diego, CA, USA). The copy number variation (CNV) detection was performed using the PennCNV algorithm. Log R ratio (LRR) and allele B frequency (BAF) were used to estimate the CNVs. The association analyses were done using the CNVRuler software and applying a logistic regression model. The phenotype was adjusted using a linear model considering the fixed effects of contemporary group and the animal age at slaughter. The fatty acid profile was analyzed on samples of longissimus thoracis muscle using gas chromatography with a 100-m capillary column. For the association analysis, the adjusted phenotypic values were considered for the traits, while the data was adjusted for the effects of the farm and year of birth, management groups at birth, weaning, and superannuation. A total of 186 CNVRs were significant for SFA (43), MUFA (42), PUFA (66), and omega fatty acid (35) groups, totaling 278 known genes. On the basis of the results, several genes were associated with several fatty acids of different saturations. Olfactory receptor genes were associated with C12:0, C14:0, and C18:0 fatty acids. The SAMD8 and BSCL2 genes, both related to lipid metabolic process, were associated with C12:0. The RAPGEF6 gene was found to be associated with C18:2 cis-9 cis-12 n-6, and its function is related to regulation of GTPase activity. Among the results, we highlighted the olfactory receptor activity (GO:0004984), G-protein-coupled receptor activity (GO:0004930), potassium:proton antiporter activity (GO:0015386), sodium:proton antiporter activity (GO:0015385), and odorant-binding (GO:0005549) molecular functions. A large number of genes associated with fatty acid profile within the CNVRs were identified in this study. These findings must contribute to better elucidate the genetic mechanism underlying the fatty acid profile of intramuscular fat in Nellore cattle. 相似文献
79.
Lívia Campos Amaral Lins Carolina Nunes França Francisco Antonio Helfenstein Fonseca Simone Pinto Melo Barbosa Lívia Nascimento Matos Ana Carolina Aguirre Henrique Tria Bianco Jonatas Bussador do Amaral Maria Cristina Izar 《Cell biochemistry and biophysics》2014,70(1):687-696
Imbalance on endothelial turnover can predict cardiovascular outcomes. We aimed at evaluating the effects of lipid-modifying therapies on circulating endothelial progenitor cells (EPCs), endothelial microparticles (EMPs), and platelet microparticles (PMPs) in high cardiovascular risk subjects with elevated C-reactive protein (CRP). Sixty-three individuals with coronary heart disease (CHD) or CHD risk equivalent on stable statin therapy, with LDL-cholesterol <100 mg/dL and CRP ≥2.0 mg/L were selected. After a 4-week run-in period with atorvastatin 10 mg, those with persistent CRP ≥2.0 mg/L were randomized to another 4-week treatment period with atorvastatin 40 mg, ezetimibe 10 mg or atorvastatin 40 mg/ezetimibe 10 mg. EPC (CD34+/CD133+/KDR+), EMP (CD51+), and PMP (CD42+/CD31+) were quantified by flow cytometry. Atorvastatin 40 mg and atorvastatin 40 mg/ezetimibe 10 mg reduced LDL-cholesterol (P < 0.001, paired T test, vs. baseline). Combined therapy, but not ezetimibe reduced CRP. CD34+/KDR+ EPC were reduced after ezetimibe alone (P = 0.011 vs. baseline, Wilcoxon test) or combined with atorvastatin (P = 0.016 vs. baseline, Wilcoxon test). In addition, ezetimibe increased CD51+ EMP (P = 0.017 vs. baseline, Wilcoxon test). No correlations between these markers and LDL-cholesterol or CRP were observed. These results contribute to understand the link between inflammation and vascular homeostasis and highlight the broader benefit of statins decreasing inflammation and preventing microparticles release, an effect not observed with ezetimibe alone. 相似文献
80.
Mário Henrique Terra‐Araujo Aparecida Donisete de Faria Anderson Alves‐Araujo Marccus Alves 《Nordic Journal of Botany》2013,31(4):437-441
Pradosia restingae Terra‐Araujo, a new species of Sapotaceae (Chrysophylloideae) from the Brazilian Atlantic forest is described and illustrated. It is only known from the southern coast of the State Rio Grande do Norte and is likely restricted to the coastal sand dune ecosystem, locally known as the restinga forest, from which the epithet is derived. The species is naturally common, but due the low number of known subpopulations we assign P. restingae a preliminary conservation status of ‘Endangered’ (EN). 相似文献