758 resultados para Developmental Ecological
Resumo:
We examined the ecological distribution of macroalgal communities in streams using species groups (taxonomic units = algal phyla, and morphological = morphological types) with similar structures and functions instead of the species themselves. The study was conducted from June to July/2007 in two drainage basins located in mid-southern region of Paraná State , Brazil. Evaluations of macroalgal communities took into consideration the following spatial scales: the drainage basin (the Pedras river and Marrecas river basins), shading regime (open and shaded stream segments), mesohabitats (riffles and pools), and microhabitats (sampling units of 0.05m2). A total of 29 taxa (23 subgeneric, one generic, and five vegetative groups) were identified. On these, 12 taxa belong to Chlorophyta, 11 to Cyanobacteria, four to Heterokontophyta, and two to Rhodophyta. The proportions of morphological types were: 24% free filaments, 17.25% mats, tufts, gelatinous colonies, and gelatinous filaments, 7% crusts. In terms of spatial scales, we observed a predominance of Chlorophyta in open stream segments and Cyanobacteria in shaded stream segments, reflecting the loss of competitive advantage of green algae in sites with low energy availability. In the mesohabitats, the morphological types recorded in pools were predominantly poorly adapted to fast currents (free filaments), while those found in riffles (mats, tufts and gelatinous filaments) were highly resistant to fast water flows. As such, the use of species groupings based on algal taxonomy associated with morphological characteristics proved to be useful to understanding the distributions of these organisms in lotic environments.
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The effects of postnatal amitraz exposure on physical and behavioral parameters were studied in Wistar rats, whose lactating dams received the pesticide (10 mg/kg) orally on days 1, 4, 7, 10, 13, 16 and 19 of lactation; control dams received distilled water (1 ml/kg) on the same days. A total of 18 different litters (9 of them control and 9 experimental) born after a 21-day gestation were used. The results showed that the median effective time (ET50) for fur development, eye opening, testis descent and onset of the startle response were increased in rats postnatally exposed to amitraz (2.7, 15.1, 21.6 and 15.3 days, respectively) compared to those of the control pups (1.8, 14.0, 19.9 and 12.9 days, respectively). The ages of incisor eruption, total unfolding of the external ears, vaginal and ear opening and the time taken to perform the grasping hindlimb reflex were not affected by amitraz exposure. Pups from dams treated with amitraz during lactation took more time (in seconds) to perform the surface righting reflex on postnatal days (PND) 3 (25.0 ± 2.0), 4 (12.3 ± 1.2) and 5 (8.7 ± 0.9) in relation to controls (10.6 ± 1.2; 4.5 ± 0.6 and 3.4 ± 0.4, respectively); the climbing response was not changed by amitraz. Postnatal amitraz exposure increased spontaneous motor activity of male and female pups in the open-field on PND 16 (140 ± 11) and 17 (124 ± 12), and 16 (104 ± 9), 17 (137 ± 9) and 18 (106 ± 8), respectively. Data on spontaneous motor activity of the control male and female pups were 59 ± 11 and 69 ± 10 for days 16 and 17 and 49 ± 9, 48 ± 7 and 56 ± 7 for days 16, 17 and 18, respectively. Some qualitative differences were also observed in spontaneous motor behavior; thus, raising the head, shoulder and pelvis matured one or two days later in the amitraz-treated offspring. Postnatal amitraz exposure did not change locomotion and rearing frequencies or immobility time in the open-field on PND 30, 60 and 90. The present findings indicate that postnatal exposure to amitraz caused transient developmental and behavioral changes in the exposed offspring and suggest that further investigation of the potential health risk of amitraz exposure to developing human and animal offsprings may be warranted.
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Norms for a battery of instruments, including Denckla's and Garfield's tests of Motor Persistence, Benton's Right-Left Discrimination, two recall modalities (Immediate and Delayed) of the Bender Test, Wechsler's Digit Span, the Color Span Test and the Human Figure Drawing Test, were developed for the neuropsychological assessment of children in the greater Rio de Janeiro area. Additionally, the behavior of each child was assessed with the Composite Teacher Rating Scale (Brito GNO and Pinto RCA (1991) Journal of Clinical and Experimental Neuropsychology, 13: 417-418). A total of 398 children (199 boys and 199 girls balanced for age) with a mean age of 9.3 years (SD = 2.8), who were attending a public school in Niterói, were the subjects of this study. Gender and age had significant effects on performance which depended on the instrument. Nonachievers performed worse than achievers in most neuropsychological tests. Comparison of our data to the available counterparts in the United States revealed that American children outperformed Brazilian children on the Right-Left Discrimination, Forward Digit Span, Color Span and Human Figure Drawing Tests. Further analysis showed that the neurobehavioral data consist of different factorial dimensions, including Human Body Representation, Motor Persistence of the Legs, Orbito-Orobuccal Motor Persistence, Attention-Memory, Visuospatial Memory, Neuropsychomotor Speed, Hyperactivity-Inattention, and Anxiety-Negative Socialization. We conclude that gender and age should be taken into account when using the normative data for most of the instruments studied in the present report. Furthermore, we stress the need for major changes in the Brazilian public school system in order to foster the development of secondary cognitive abilities in our children
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Norms for the Gardner Steadiness Test and the Purdue Pegboard were developed for the neuropsychological assessment of children in the metropolitan area of Rio de Janeiro. A computer-generated unbiased sample of 346 children with a mean age of 9.4 years (SD = 2.76), who were attending a large normal public school in this urban area, was the subject of this study. Two boys were removed from the study, one for refusing to participate and the other due to severe strabismus. Therefore, the final sample contained 344 children (173 boys and 171 girls). Sex and age of the child and hand preferred for writing, but not ethnic membership or social class, had significant effects on performance in the Gardner Steadiness Test and the Purdue Pegboard. Girls outperformed boys. Older children performed better than younger children. However, the predictive relationship between age of the child and neuropsychological performance included linear and curvilinear components. Comparison of the present results to data gathered in the United States revealed that the performance of this group of Brazilian children is equivalent to that of US children after Bonferroni's correction of the alpha level of significance. It is concluded that sex and age of the child and hand preferred for writing should be taken into account when using the normative data for the two instruments evaluated in the present study. Furthermore, the relevance of neurobehavioral antidotes for the obliteration of some of the probable neuropsychological effects of cultural deprivation in Brazilian public school children is hypothesized.
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This article proposes a comprehensive view of the origin of the mammalian brain. We discuss i) from which region in the brain of a reptilian-like ancestor did the isocortex originate, and ii) the origin of the multilayered structure of the isocortex from a simple-layered structure like that observed in the cortex of present-day reptiles. Regarding question i there have been two alternative hypotheses, one suggesting that most or all the isocortex originated from the dorsal pallium, and the other suggesting that part of the isocortex originated from a ventral pallial component. The latter implies that a massive tangential migration of cells from the ventral pallium to the dorsal pallium takes place in isocortical development, something that has not been shown. Question ii refers to the origin of the six-layered isocortex from a primitive three-layered cortex. It is argued that the superficial isocortical layers can be considered to be an evolutionary acquisition of the mammalian brain, since no equivalent structures can be found in the reptilian brain. Furthermore, a characteristic of the isocortex is that it develops according to an inside-out neurogenetic gradient, in which late-produced cells migrate past layers of early-produced cells. It is proposed that the inside-out neurogenetic gradient was partly achieved by the activation of a signaling pathway associated with the Cdk5 kinase and its activator p35, while an extracellular protein called reelin (secreted in the marginal zone during development) may have prevented migrating cells from penetrating into the developing marginal zone (future layer I).
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Tämän eksploratiivisen tutkimuksen tarkoituksena on tutkia yrittäjän persoonallisuuden roolia ekologisesti suuntautuneen brändin identiteetin ja assosiaatioiden rakentamisessa. Tutkimus on tehty yrittäjän näkökulmasta, jonka kontekstina ovat pienet ja keskisuuret yritykset. Tämä tutkimus pyrkii laajentamaan ja saamaan ymmärrystä keskeisistä käsitteistä, ja samalla edistämään PK-yrityksiin liittyvää kirjallisuutta. Tämän lisäksi tutkimus tarkastelee mitä assosiaatioita ekologisesti suuntautunut brändi korostaa identiteetissään. Tutkimus suoritettiin tapaustutkimuksena. Laadullista primääridataa kerättiin teemahaastattelemalla yrittäjää, havainnoimalla yhtä case-yrityksen messuosastoa, sekä keräämällä yrittäjän persoonallisuusattribuutteja. Jotta tutkimus saavuttaisi myös datan triangulaation, sekundääristä dataa kerättiin vahvistamaan aiempaa tutkimusta. Yhtenä sekundäärilähteenä toimivat kaksi artikkelia, jotka auttoivat vahvistamaan aiemmin esiin nostetut yrittäjän persoonallisuusattribuutit. Persoonallisuusattribuutteja verrattiin case-yrityksen brändin identiteettiin, jotta yrittäjän persoonallisuuden rooli brändin identiteetin rakentamisessa saataisiin selville. Tulokset osoittivat yhteyden brändin identiteetin ja yrittäjän persoonallisuuden välillä ekologisesti suuntautuneessa case-yrityksessä. Tulokset paljastivat myös joitakin yleisiä assosiaatioita joita luodaan ja vahvistetaan brändin identiteetin eri osa-alueiden avulla.
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The objective of the present study was to examine the effect of green tea polyphenols (GTPs) supplementation during in vitro maturation, in vitro fertilization, and in vitro culture on the developmental competence of bovine oocytes. Cumulus-oocyte complexes aspirated from the ovaries were matured in vitro (38.5ºC for 24 h) and fertilized (38.5ºC for 15-18 h) and embryos were cultured (38.5ºC for 192 h) in a defined conditioned medium with or without GTPs supplementation. The GTPs used in the present study contained 99% catechin derivatives, with the major components being 50% (-)-epigallocatechin gallate, 22% (-)-epicatechin gallate, 18% (-)-epigallocatechin, and 10% (-)-epicatechin. Four replicate trials were done for each type of experiment. GTPs supplementation (15 µM) of the maturation medium led to a significant increase in the rate of blastocyst formation (34.0 vs 21.4%, P < 0.05). However, the rate of blastocyst formation was not improved when higher GTPs concentrations (20 or 25 µM) were added to the in vitro maturation medium. During in vitro fertilization, supplementation with higher GTPs concentrations (20 or 25 µM) significantly reduced the rate of blastocyst formation (P < 0.05). Supplementation of the culture medium with 15 µM GTPs improved the rate of blastocyst formation, while higher GTPs concentrations (25 µM) significantly reduced embryo development (P < 0.05). In conclusion, these results demonstrate that supplementation with GTPs at low concentration (15 µM) during in vitro maturation and in vitro culture improved the developmental competence of bovine oocytes.
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Many internationally adopted children have lived their first years of life in an environment with limited opportunities for primary caregiving. The lack of consistent care increases the prevalence of attachment disorders among them. Less is known about the influences of attachment disorders on a child’s later course of life. This study is part of the Finnish Adoption Study. Parents of all Finnish children who had been internationally adopted by legal adoption organisations between 1985 and 2007 were sent questionnaires (N=1450). Parental evaluations of the children’s symptoms of reactive attachment disorder (RAD) at the time of adoption, their later learning or language problems using a screening scale, and children’s self-reported school bullying experiences were evaluated. Each child’s attachment-related behavioural problems were requested in a follow-up survey 1.9 and 3.8 years after adoption and compared with a Finnish reference group. This study indicated that Finnish internationally adopted children have at least three-fold prevalence of learning and language problems compared with their age-mates. A child’s symptoms of attachment disorders were associated with learning or language problems at school age as well as with his/her school bullying experiences. The adopted children had more attachment-related behavioural problems two years after adoption than their age-mates, but the difference was no longer evident four years after adoption. In conclusion, this study showed that the symptoms of attachment disorder indicate a risk for an adopted child’s later developmental outcome. The findings demonstrate the need for comprehensive clinical examinations and planning of treatment strategies for children with symptoms of RAD.
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Beetroot leaves (Beta vulgaris L.) are commonly cut off and discarded before using its bulb due to lack of knowledge of how to use them. Aiming at using these leaves, in the present study, in natura and dehydrated beetroot leaves were chemically characterized in terms of fatty acid composition, proximate composition, minerals, total phenolic compounds (TPC), and antioxidant activity by DPPH in different stages (60, 80, and 100 days) of development. The beetroot leaves showed significant levels of protein and lipids in all developmental stages, and all proximate composition nutrients decreased during these maturation stages; the highest content was observed at 60 days. The Fe content decreased during the developmental stages (from 342.75 to 246.30 mg.kg-1), while the content of K increased (from 13,367.64 to 20,784.90 mg.kg-1). With regard to to fatty acid composition, linolenic acid was present in the greatest quantity, and it increase up to 2.58 mg.g-1 (in natura) and 40.11 mg.g-1 (dehydrated) at 100 days of development. The n-6/n-3 ratios were low in all stages. The TPC and antioxidant activity by DPPH changed during the developmental stages. The TPC was highest in the 100-day dehydrated leaves (15.27±0.12 mg GAE.g-1 FW), and the 50% inhibition of DPPH (IC50 89.52 µg.mL-1) were better in the 60-day in natura leaves. This study shows that all developmental stages produced satisfactory results, and therefore, these leaves can be reused as food. The antioxidant activity and the chemical constituents, mainly the ω-3fatty acid, increased during the stages of development.
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Sweet potato is an important staple, and it is mainly known for its contribution of β-carotene in human diet. The effects of cultivar and habitat on this pigment and other nutritional characteristics of the crop still require investigation. In this study, three locally bred cultivars of sweet potato, two of which are orange-fleshed, were grown in three different agro-ecological areas to determine soluble sugar content, β-carotene, and total antioxidants of roots. In addition antioxidant activity, total carotenoids, and chlorophyll content were determined in edible leaves. Reducing sugars, β-carotene, total antioxidants capacity, total carotenoids, and chlorophyll content were significantly affected by environmental conditions. The location at lower altitude and closer to the coastline showed high evapotranspiration, thus reducing sugar content, antioxidant activity, and phytonutrients in both storage roots and leaves. Absence of water stress in agro-ecological locations further inland and at higher altitudes was associated with an increase in these compounds. Free radical scavenging activity of DPPH was higher in the storage roots (610.49 µmoles TE/100g) than in the leaves (426.06 µmoles TE/100g); nevertheless, opposite results were found for the ferric ion reducing activity (FRAP). The deep orange-fleshed cultivar A45 contained high β-carotene (15 mg/100g), which is enough to meet RDA for vitamin A. There is evidence of agro-ecological effect on sweet potato nutritional value.
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The main goal of our paper is to provide analytical arguments to explain why Brazil has not been able to restore its long-term capacity for economic growth, especially compared with its economy in the 1950-1979 period (7.3 per cent per year on average) or even with a select number of emerging economies in the 1980-2010 period(6.7 per cent per year on average, against 2.3 per cent per year on average in Brazil in the same period). We build our idea of convention to growth based on the Keynesian concept of convention. For our purposes, this concept could be briefly summarized as the way in which the set of public and private economic decisions related to different objectives, such as how much to produce and invest, how much to charge for products and services, how to finance public and private debt, how to finance research and development, and so on, are indefinitely - or at least until there is no change- carried out by the political, economic and social institutions. This analytical reference can be connected to the Neo-Schumpeterian National Innovation System (NIS) concept, which emphasizes not only institutions associated with science and technology per se, but also the complex interaction among them and other institutions. In this paper we identify two conventions to long-term growth in the last three decades in Brazil: the liberal and the neo-developmental. We show that the poor performance in the Brazilian economy in terms of real GDP growth from the 1980s on can be explained by a weak coordination between short-term macroeconomic policies and long-term industrial and technological policies. This weak coordination, in turn, can be associated with the prevalence of the liberal convention from the 1990s on, which has emphasized price stabilization to the detriment of a neo-developmental strategy whose primary goal is to sustain higher rates of growth and full employment in Brazil.
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The record of successful developmental states in East Asia and the partial successes of developmental states in Latin America suggest several common preconditions for effective state intervention including a Weberian bureaucracy, monitoring of implementation, reciprocity (subsidies in exchange for performance), and collaborative relations between government and business. Although Brazil failed to develop the high technology manufacturing industry and exports that have fueled sustained growth in East Asia, its developmental state had a number of important, and often neglected, successes, especially in steel, automobiles, mining, ethanol, and aircraft manufacturing. Where Brazil's developmental state was less successful was in promoting sectors like information technology and nuclear energy, as well as overall social and regional equality. In addition, some isolated initiatives by state governments were also effective in promoting particular local segments of industry and agriculture. Comparisons with East Asia, highlight the central role of state enterprises in Brazil that in effect internalized monitoring and reciprocity and bypassed collaboration between business and government (that was overall rarer in Brazil).
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Our surrounding landscape is in a constantly dynamic state, but recently the rate of changes and their effects on the environment have considerably increased. In terms of the impact on nature, this development has not been entirely positive, but has rather caused a decline in valuable species, habitats, and general biodiversity. Regardless of recognizing the problem and its high importance, plans and actions of how to stop the detrimental development are largely lacking. This partly originates from a lack of genuine will, but is also due to difficulties in detecting many valuable landscape components and their consequent neglect. To support knowledge extraction, various digital environmental data sources may be of substantial help, but only if all the relevant background factors are known and the data is processed in a suitable way. This dissertation concentrates on detecting ecologically valuable landscape components by using geospatial data sources, and applies this knowledge to support spatial planning and management activities. In other words, the focus is on observing regionally valuable species, habitats, and biotopes with GIS and remote sensing data, using suitable methods for their analysis. Primary emphasis is given to the hemiboreal vegetation zone and the drastic decline in its semi-natural grasslands, which were created by a long trajectory of traditional grazing and management activities. However, the applied perspective is largely methodological, and allows for the application of the obtained results in various contexts. Models based on statistical dependencies and correlations of multiple variables, which are able to extract desired properties from a large mass of initial data, are emphasized in the dissertation. In addition, the papers included combine several data sets from different sources and dates together, with the aim of detecting a wider range of environmental characteristics, as well as pointing out their temporal dynamics. The results of the dissertation emphasise the multidimensionality and dynamics of landscapes, which need to be understood in order to be able to recognise their ecologically valuable components. This not only requires knowledge about the emergence of these components and an understanding of the used data, but also the need to focus the observations on minute details that are able to indicate the existence of fragmented and partly overlapping landscape targets. In addition, this pinpoints the fact that most of the existing classifications are too generalised as such to provide all the required details, but they can be utilized at various steps along a longer processing chain. The dissertation also emphases the importance of landscape history as an important factor, which both creates and preserves ecological values, and which sets an essential standpoint for understanding the present landscape characteristics. The obtained results are significant both in terms of preserving semi-natural grasslands, as well as general methodological development, giving support to science-based framework in order to evaluate ecological values and guide spatial planning.
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The oscillation of neuronal circuits reflected in the EEG gamma frequency may be fundamental to the perceptual process referred to as binding (the integration of various thoughts and perceptions into a coherent picture). The aim of our study was to expand our knowledge of the developmental course ofEEG gamma in the auditory modality. 2 We investigated EEG 40 Hz gamma band responses (35.2 to 43.0 Hz) using an auditory novelty oddball paradigm alone and with a visual-number-series distracter task in 208 participants as a function of age (7 years to adult) at 9 sites across the sagital and lateral axes (F3, Fz, F4, C3, Cz, C4, P3, Pz, P4). Gamma responses were operationally defined as change in power or a change in phase synchrony level from baseline within two time windows. The evoked gamma response was defined as a significant change from baseline occurring between 0 to 150 ms after stimulus onset; the induced gamma response was measured from 250 to 750 ms after stimulus onset. A significant evoked gamma band response was found when measuring changes in both power and phase synchrony. The increase in both measures was maximal at frontal regions. Decreases in both measures were found when participants were distracted by a secondary task. For neither measure were developmental effects noted. However, evoked gamma power was significantly enhanced with the presentation of a novel stimulus, especially at the right frontal site (F4); frontal evoked gamma phase synchrony also showed enhancement for novel stimuli but only for our two oldest age groups (16-18 year olds and adults). Induced gamma band responses also varied with task-dependent cognitive stimulus properties. In the induced gamma power response in all age groups, target stimuli generated the highest power values at the parietal region, while the novel stimuli were always below baseline. Target stimuli increased induced synchrony in all regions for all participants, but the novel stimulus selectively affected participants dependent on their age and gender. Adult participants, for example, exhibited a reduction in gamma power, but an increase in synchrony to the novel stimulus within the same region. Induced gamma synchrony was more sensitive to the gender of the participant than was induced gamma power. While induced gamma power produced little effects of age, gamma synchrony did have age effects. These results confirm that the perceptual process which regulates gamma power is distinct from that which governs the synchronization for neuronal firing, and both gamma power and synchrony are important factors to be considered for the "binding" hypothesis. However, there is surprisingly little effect of age on the absolute levels of or distribution of EEG gamma in the age range investigated.