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Cognitive tests of inhibitory control show variable results for the differential diagnosis between behavioural variant of Frontotemporal Dementia (bvFTD) and Alzheimer’s disease (AD). We compared the diagnostic accuracies of tests of inhibitory control and of a behavioural questionnaire, to distinguish bvFTD from AD.
Three groups of participants were enrolled: 27 bvFTD patients, 25 AD patients, and 24 healthy controls. Groups were matched for gender, education, and socio-economic level. Participants underwent a comprehensive neuropsychological assessment of inhibitory control, including Hayling Test, Stroop, the Five Digits Test (FDT) and the Delay Discounting Task (DDT). Caregivers completed the Barratt Impulsiveness Scale 11th version (BIS-11).
bvFTD and AD groups showed no difference in the tasks of inhibitory control, while the caregiver questionnaire revealed that bvFTD patients were significantly more impulsive (BIS-11: bvFTD 76.1+9.5, AD 62.9+13, p < .001).
Neuropsychological tests of inhibitory control failed to distinguish bvFTD from AD. On the contrary, impulsivity caregiver-completed questionnaire provided good distinction between bvFTD and AD. These results highlight the current limits of cognitive measures of inhibitory control for the differential diagnosis between bvFTD and AD, whereas questionnaire information appears more reliable and in line with clinical diagnostics.
The addition of growth factors and vitamins enhances goat embryonic development in vitro. However, few attempts have been reported trying to identify supplementation regimens for oocyte maturation or embryo culture with additive properties. The present report was aimed to evaluate if retinoids [0.3 μM retinyl acetate (RAc) and 0.5 μM 9-cis-retinoic acid (RA)] supplementation during goat oocyte maturation and retinoids and/or 50 ng mL–1 IGF-I during embryo culture synergically enhanced embryonic development while diminishing the incidence of apoptosis. All combinations of RAc and RA treatment produced blastocysts with similar efficiencies, while IGF-I enhanced embryos yields irrespectively of retinoid addition. Moreover, retinoids and IGF-I supplementation showed similar caspase activity or DNA fragmentation indexes in blastocysts. In conclusion, supplementation with retinoids and IGF-I during goat embryo culture enhances blastocysts development without synergic reduction of apoptosis.
Composites of 8 mol% yttria-stabilized zirconia (YSZ) and titanium nitride (TiN) were obtained by mechanical mixing of commercial powders. High-density samples of (1-x) YSZ / x TiN, with x = 0, 25, 50, and 75 wt.%, were obtained by spark plasma sintering (SPS) at 1450 °C for 5 min. Surface contamination with carbon from the SPS was eliminated by diamond sawing of parallel surfaces. X-rays diffraction analyses showed that samples are composed by a mixture of the initial phases, without appreciable reaction as inferred from calculated lattice parameters. dc 4-probe electrical measurements in the 100-850°C under showed that samples have a metallic behavior, indicating that the percolation threshold was attained for the sample with the lowest content of the TiN (x=25 wt.%), which corresponds to ∼27 vol.%.
Species of Miconia are considered keystone plant resources for frugivorous birds in Neotropical forests, but for other ecosystems little of their ecological role is known. The fruiting phenology and the composition of frugivores of four Miconia species in savanna and palm swamp from the Brazilian Neotropical savanna were studied in three sites from November 2005 to May 2011. The hypothesis tested was that plants from different habitats share their frugivores and consequently promote links between habitats. Through focal plant observations (30–50 h per species in each site), 668 visits by 47 species of birds were recorded and plants from different habitats shared most of the frugivores (49–97%). The fruiting of Miconia chamissois in the palm swamp during the period of fruit scarcity (dry season) was accompanied by an enhancement in the frugivore bird richness and abundance in this habitat, providing indirect evidence of resource tracking. Bird species which primarily dwell in savanna recorded consuming fruits in palm swamps during the resource-scarce season is taken as evidence of landscape supplementation. Miconia assemblage studied here seems to promote a link between two adjacent habitats in the Neotropical savanna from Central Brazil, a link which is likely to be common in this naturally patchy ecosystem.
There is great difficulty in maintaining aquatic mammals in captivity, since the attempt to replicate the environment they live in poses an enormous challenge. Poor captivity facilities without environmental enrichment can lead to different consequences for animal health, including the appearance of stereotypical movements. The aim of this study was to identify these behaviours in three groups of animals, one group of manatees inhabiting a reintroduction oceanarium in Pernambuco (PE) state, and two other groups confined in corrals constructed in natural areas (estuaries), one located in Paraiba state and the other in Alagoas state, all in north-eastern Brazil. Observations were conducted using the focal animal sampling method. It was found that the animals inhabiting the reintroduction oceanarium with no environmental enrichment showed stereotypical behaviour such as ‘Back-and-forth’ movements, ‘Hitting head against the limiting structure’ and ‘Hitting the muzzle’, while animals constrained within estuaries did not. The ‘circle swimming’ behaviour was present in a higher percentage of the animals captive in the reintroduction oceanarium, although no significant difference between the sites was found. The number and frequency of occurrence of stereotypical behaviours was significantly higher in animals kept in the reintroduction oceanarium in PE than in those of other locations. Based on these results we recommend the use of appropriate environmental enrichment and the reduction of time manatees stay confined in the reintroduction oceanarium.
The age and growth of the snowy grouper, Epinephelus niveatus, from central and south-eastern Brazil were studied by otolith analysis from a sample of 341 specimens, ranging from 325 to 1216 mm in total length (TL) caught with bottom longlines between 1996 and 1998. Otolith length grew proportionally with the increasing TL of the fish. Marginal increment analysis indicated that a single opaque band forms each year during autumn–winter. The maximum estimated age was 54 years, which significantly extends the previously estimated life-span of 21–29 years for this species. The von Bertalanffy growth parameters for both sexes were estimated as L∞ = 1098.4 mm TL, K = 0.062 year −1 and t0 = –2.68. The study revealed differences in mean length-at-age and size at recruitment, as well as in growth parameters between the central and the south-eastern Brazilian coast, which can be attributed mainly to different fishing pressures. The snowy grouper was found at depths of 82–492 m, and showed a positive relationship between age and depth, suggesting differential movements of older fish to deeper waters.
This article presents biological data and an assessment of the conservation of the olive ridley sea turtle (Lepidochelys olivacea) population nesting in the States of Sergipe and Bahia, north-eastern Brazil, between 1991/1992 and 2002/2003. Projeto TAMAR-IBAMA (the Brazilian Sea Turtle Conservation Programme) maintains seven field stations in that region to monitor nesting activity over 339 km of beach. An increasing trend was observed in the estimated number of nests per nesting season: from 252 nests in 1991/1992 to 2606 in 2002/2003, an approximately 10-fold increase in 11 years. The available data and biological knowledge suggest that TAMAR's conservation efforts may have contributed to the significant increase in olive ridley nesting in Sergipe and Bahia; that increase is not only of regional importance, but also of significance at the western Atlantic level.
Here, we describe the development of an inexpensive and versatile
manipulation system for in situ experiments in a field emission
scanning electron microscope based on a parallel-guiding plate-spring
mechanism and low cost materials. The system has been tested for a wide
range of applications, such as collecting, moving, and positioning
particles, fabricating atomic force microscopy tips based on carbon
nanotubes, and characterizing individual nanobjects. The nanomanipulation
results demonstrate that there are many opportunities for the use of
physical manipulation in the bottom-up approach to fabrication of
The reproductive process of two species of Kielmeyera, K. coriacea and K. speciosa, sympatric in savanna areas in central Brazil, has been studied. The trees have similar pollination systems and dispersal mechanisms but distinct phenological behaviours. Fast germination after the beginning of the wet season, early root swelling forming a xylopodium which enables survival during the dry season, and recurrent sprouting from the swollen root system during the first years of development were features of an establishment syndrome common to both species. The seedling survival after establishment was high; after five years 64% of the seedling cohort of K. coriacea was still alive. These seedlings, in natural conditions, remain poorly developed and resprout recurrently from the soil during some years. The recruitment of adult plants seems to occur from this ‘seedling bank’. The reproductive process was higher in K. coriacea during most stages of the reproductive process which may explain the smaller population size and distribution range of K. speciosa. For both species, the reproductive process as a whole was mainly affected by biotic factors in the wet season and not by seasonal drought or periodic fire.
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