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311.
Oscar Fernandes Júnior Filipe Martins Santos Wesley Arruda Gimenes Nantes William Oliveira de Assis Gisele Braziliano de Andrade 《Studies on Neotropical Fauna and Environment》2020,55(2):149-154
ABSTRACT Azaras’s capuchin monkey (Sapajus cay) is a poorly studied species in ecological aspects. We investigated behavioral activities and diet of a group of S. cay in a remnant of the Brazilian Cerrado. We sought to identify the most frequent behavior that the group engaged in, as well as to verify possible differences in behavioral patterns and diet between adult males and females. From January to July 2012 we collected behavioral and foraging data for a group of 21 individuals using scan sampling. Behaviors and food items consumed were analyzed using percentages and two proportions Z-tests to assess differences between males and females. We obtained 878 scans in approximately 202 hours of sampling effort, resulting in 4,159 individual activity records of capuchin monkeys. The group allocated time to traveling (41.3%), resting (25.5%), feeding (14.3%), foraging (13.7%), and social activities (5.1%). Females spent more time foraging and feeding, while males spent more time resting. Fruits (61.4%), invertebrates (15.3%), and seeds (14.3%) were the most common food items consumed. We did not find differences in food consumption between sexes. Behavioral activities may be influenced by habitat quality of the studied area, opportunistic habits, and plasticity in the diet. 相似文献
312.
Gisele Ringeard 《Ocean Development & International Law》2013,44(2):121-136
Abstract It is traditional to consider that scientific research should be free. During the past, it has been affected by material and intellectual constraints; these constraints have evolved but exist still today. Because of the unity of the ocean, researchers, and especially oceanographers, claim a scientific immunity for their work. Because of the resources of the oceans, governments explicitly or implicitly consider freedom of scientific research as an application of the doctrine of economic liberalism, with its advantages and its disadvantages. Be that as it may, scientific research is absolutely necessary. To make compatible the demands of researchers and governments, freedom may become deontology. Researchers receive from authorities the largest rights of circulation applying to individuals, to materials, and to ideas. Researchers have, in counterpart, the duty to protect, to develop and to share the knowledge resulting from their work. 相似文献
313.
Monica Visnieski Alcantara Stenio Perdig?o Fragoso Gisele Fernanda Assine Picchi/ 《Memórias do Instituto Oswaldo Cruz》2014,109(4):511-513
Gene knockout is a widely used approach to evaluate loss-of-function phenotypes
and it can be facilitated by the incorporation of a DNA cassette having a
drug-selectable marker. Confirmation of the correct knockout cassette insertion
is an important step in gene removal validation and has generally been performed
by polymerase chain reaction (PCR) assays following a time-consuming DNA
extraction step. Here, we show a rapid procedure for the identification of
Trypanosoma cruzi transfectants by PCR directly from liquid
culture - without prior DNA extraction. This simple approach enabled us to
generate PCR amplifications from different cultures varying from
106-108 cells/mL. We also show that it is possible to
combine different primer pairs in a multiplex detection reaction and even to
achieve knockout confirmation with an extremely simple interpretation of a
real-time PCR result. Using the “culture PCR” approach, we show for the first
time that we can assess different DNA sequence combinations by PCR directly from
liquid culture, saving time in several tasks for T. cruzi
genotype interrogation. 相似文献
314.
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316.
Yugo Lima‐Melo Fabricio E. L. Carvalho Márcio O. Martins Gisele Passaia Rachel H. V. Sousa Milton C. Lima Neto Márcia Margis‐Pinheiro Joaquim A. G. Silveira 《植物学报(英文版)》2016,58(8):737-748
The physiological role of plant mitochondrial glutathione peroxidases is scarcely known. This study attempted to elucidate the role of a rice mitochondrial isoform(GPX1) in photosynthesis under normal growth and salinity conditions. GPX1 knockdown rice lines(GPX1s) were tested in absence and presence of 100 mM NaCl for 6 d.Growth reduction of GPX1 s line under non-stressful conditions, compared with non-transformed(NT) plants occurred in parallel to increased H_2O_2 and decreased GSH contents. These changes occurred concurrently with photosynthesis impairment, particularly in Calvin cycle's reactions, since photochemical efficiency did not change.Thus, GPX1 silencing and downstream molecular/metabolic changes modulated photosynthesis differentially. In contrast, salinity induced reduction in both phases of photosynthesis, which were more impaired in silenced plants.These changes were associated with root morphology alterations but not shoot growth. Both studied lines displayed increased GPX activity but H_2O_2 content did not change in response to salinity. Transformed plants exhibited lower photorespiration, water use efficiency and root growth, indicating that GPX1 could be important to salt tolerance. Growth reduction of GPX1 s line might be related to photosynthesis impairment, which in turn could have involved a cross talk mechanism between mitochondria and chloroplast originated from redox changes due to GPX1 deficiency. 相似文献
317.
Optically active lumazines (biolumazine, dictyolumazine, monalumazine, and neolumazine) are prepared from the corresponding pterins by enzymatic reaction, using pterin deaminase excreted by Dictyostelium discoideum. The fluorescence properties, circular dichroism spectra, and chromatographic behavior of these lumazines are studied. D - and L -enantiomers of biolumazine, dictyolumazine, and monalumazine are separated using a chiral flavoprotein column. This column also separates the enantiomeric pterins of the threo form: monapterin and dictyopterin. However, the column does not separate the enantiomeric pterins of the erythro form: neopterin and biopterin. By coupling a reverse-phase column to the flavoprotein column, the separation of pterins and lumazines in function of their hydrophobicity, as well as the separation of the diastereomers, is achieved. This coupled achiral/chiral high-performance liquid chromatography method enables determination of the stereoconfiguration of natural lumazines by comparison with optically pure compounds. A lumazine derivative, present in the extracellular medium of Dictyostelium discoideum, is identified as D -dictyolumazine, i.e., 6-(D -threo-1,2-dihydroxypropyl)-lumazine. © 1994 Wiley-Liss, Inc. 相似文献
318.
319.
Valeria Boeris Laura Verónica Cappella Gisele Peres Inés Burgos Nádya Pesce da Silveira Gerardo Fidelio Guillermo Picó 《Biotechnology and Bioprocess Engineering》2013,18(3):538-545
Eudragit® L100 (EuL) and Eudragit® S100 (EuS) are synthetic polyanions differing on their electric charge density. They interact with chymotrypsin (ChTRP), a basic protein forming soluble and non-soluble complexes. The complex formation was studied by dynamic light scattering, isothermal titration calorimetry, native fluorescence emission, circular dichroism and thermodynamical thermal stability of the enzyme. EuS was able to bind 33 ChTRP molecules while EuL, 60. The binding of ChTRP to both Eu was slightly endothermic and the entropic factor was responsible for the soluble complexes formation. The ChTRP-Eu size increases with pH and the binding of ChTRP to Eu modifies the Eu hydrodynamic radium. The interaction of ChTRP with Eu did not modify its secondary or tertiary structure. The thermal stability of ChTRP was increased when it interacted with both Eu. 相似文献
320.
Gentilin-Avanci Camila Pinha Gisele D. Petsch Danielle K. Mormul Roger P. Thomaz Sidinei M. 《Limnology》2021,22(1):129-138
Limnology - Exotic species have invaded freshwater ecosystems, causing biodiversity loss of associated communities. We investigated the influence of the invasive macrophyte Hydrilla verticillata on... 相似文献