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761.
María Isabel Martínez‐Nieto José Gabriel Segarra‐Moragues Encarnación Merlo Fabián Martínez‐Hernández Juan Francisco Mota 《Botanical journal of the Linnean Society. Linnean Society of London》2013,173(4):654-675
Iberian gypsum outcrops are highly fragmented and ecologically challenging environments for plant colonization. As gypsophytes occur exclusively in such habitats, they are ideal models for the study of both the effects of habitat fragmentation and selection on population genetic diversity and structure. In this study, we used amplified fragment length polymorphism (AFLP) and plastid DNA sequences to investigate the phylogeographical history of the Iberian plant Gypsophila struthium (Caryophyllaceae), a widespread endemic restricted to Iberian gypsum outcrops. Gypsophila struthium consists of two subspecies that differ in the architecture of their inflorescence and have mostly allopatric ranges. Gypsophila struthium subsp. struthium occurs in central, eastern and south‐eastern Iberia, whereas G. struthium subsp. hispanica occurs in northern and eastern areas. AFLPs revealed low but significant genetic differentiation between the subspecies, probably as a result of a recent diversification during the Pliocene–Pleistocene. In the geographical contact zone between the taxa, the Bayesian analyses revealed populations with mixed ancestries and genetic clusters predominantly of one or the other subspecies, indicating incomplete reproductive barriers between them. Plastid DNA haplotypes revealed strong geographical structure and testified to processes of isolation by distance and continuous range expansion for some haplotype clades. The Bayesian analyses of the population structure of AFLP data and nested clade phylogeographical analysis (NCPA) of plastid haplotypes revealed that the putative ancestral range corresponded to central and eastern populations of G. struthium subsp. struthium, with those lineages contributing through more recent expansion to increased genetic diversity and structure of the south‐eastern and eastern ranges of this subspecies and to the diversification of G. struthium subsp. hispanica in northern and eastern gypsum outcrops. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173 , 654–675. 相似文献
762.
The new taxonMoehringia intricata subsp.giennensis, from the calcareous mountains of the south-eastern Iberian Peninsula is described. A comparative morphological study with regard to the most closely related taxa, contributes information of leaf anatomy, seed and pollen morphology, ecology and distribution. 相似文献
763.
Maricele Nascimento Barbosa Maria Teresa da Silva Mota 《Primates; journal of primatology》2014,55(2):293-302
Parental care in mammals is influenced by sensory stimuli from infants, such as sight and sound, and by changes in the hormone levels of caretakers. To determine the responsiveness of common marmoset (Callithrix jacchus) adult males with and without previous experience in caretaking to newborn sensory cues, we exposed twelve males to infant vocalization recordings and assessed their hormonal and behavioral responses. Males were placed in the testing cage for 10 min under two conditions: (a) control condition (exposure to adult conspecific vocalization recordings), and (b) experimental condition (exposure to infant vocalization recordings). We recorded the frequency of approach towards the sound source, the time spent near it and locomotion frequency of males in the cage under both conditions. Blood samples were collected after each test for cortisol, measured by the enzyme immunoassay method. Infant vocalization affects the behavioral and hormonal responses of non-reproductive male common marmosets. All males approached and spent more time near the sound source and showed an increase in locomotion during infant vocalization exposure compared to the control condition. Successive exposure to infant vocalization increased the responsiveness in inexperienced males. Cortisol levels were significantly higher following infant vocalization exposure compared to the control condition. These findings support the assumption that sound stimuli from the newborn are critical in initiating and maintaining caretaker responsiveness and that cortisol seems to be important for alertness to sensory stimuli, modulating their motivation to interact with infants. 相似文献
764.
Poliana de Oliveira Figueiredo André Tavares da Silva-Fernandes Bruno Eduardo Fernandes Mota Galileu Barbosa Costa Iara Apolinário Borges Paulo César Peregrino Ferreira J?natas Santos Abrah?o Erika Martins Braga Erna Geessien Kroon Giliane de Souza Trindade 《Memórias do Instituto Oswaldo Cruz》2015,110(6):804-808
Vaccinia virus naturally circulates in Brazil and is the causative agent of a
zoonotic disease known as bovine vaccinia (BV). We retrospectively evaluated two
populations from the Amazon and Southeast Regions. BV outbreaks had not been reported
in these regions before sample collection. Neutralising antibodies were found in 13
individuals (n = 132) with titres ranging from 100 ≥ 6,400 neutralising units/mL.
Univariate analysis identified age and vaccination as statistically significant risk
factors in individuals from the Southeast Region. The absence of detectable
antibodies in vaccinated individuals raises questions about the protection of
smallpox vaccine years after vaccination and reinforces the need for surveillance of
Orthopoxvirus in Brazilian populations without evidence of previous outbreaks. 相似文献
765.
Carla Freitas António A. Vicente Manuel Mota José A. Teixeira 《Biotechnology Techniques》1997,11(7):489-492
Measurement of solids hold-up in gas-liquid-solid systems was achieved by using a cylinder with a valve in each extremity, which allowed direct sampling inside the reactor causing minimal disturbances to the fluid flow. The method was developed and tested in a 60 L concentric draught tube airlift reactor. Validation of the method was done by means of an overall balance to the solid phase in the bioreactor. 相似文献
766.
767.
B R Cordenunsi J R Oliveira do Nascimento R Vieira da Mota F M Lajolo 《Bioscience, biotechnology, and biochemistry》2001,65(10):2174-2180
Some characteristics of phosphoglucose isomerase (PGI, EC 5.3.1.9) from banana were measured during fruit ripening of three banana cultivars. In banana, PGI was present as two dimeric isoenzymes, named PGI1 and PGI2, which had similar native molecular masses but differed in relation to heat stability and isoelectric point. Total PGI activity showed a distinct two-step change during fruit ripening. Before the climacteric period, PGI activity gradually decreased with the starch content, then its activity began to increase with sucrose accumulation. The ratio of PGI1, and PGI2 was constant, indicating that both enzymes would be involved in starch degradation and sucrose synthesis. PGI activity and changes in carbohydrate composition suggests the existence of some control to fit the requirements of the intense carbon flow from starch to sucrose. 相似文献