825 resultados para Emerging and mature destinations
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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We investigated the reproductive biology of Knodus moenkhausii, an abundantsmall-sized characin fish with broad occurrence in the Parana River basin, Bra-zil. Specimens were collected monthly to determine fecundity, length at firstmaturity, reproductive period and spawning type. Gonads were macroscopically classified according to their form, size and texture in three different stages(immature, maturing or mature). Histological procedures were conducted toconfirm gonadal developmental stages, and it was possible to notice thatmaturing females actually presented atretic oocytes, and all males that weremacroscopically classified as immature, maturing and mature actually presentedabundant spermatozoa in their gonads. Because of these discrepancies, a reclas-sification of gonadal maturations stages was needed after histological analysis,reinforcing its importance to studies on the reproduction of small characins.Reproduction occurred throughout the year though with two peaks. The lengthof the smallest mature individuals was 13 mm SL for males and 24 mm SL for females. Despite presenting relatively small batch fecundity, some life historytraits such as early reproduction, multiple spawning throughout the year, inassociation with known opportunistic feeding habits, explain the high abun-dance of this species in locations where it occurs.
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Coordenação de Aperfei çoamento de Pessoal de Nível Superior (CAPES)
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During the last decade, leaf tatters has been reported in white oak and hackberry across several Midwestern states. Herbicide spray drift studies have shown that chloroacetamides can induce leaf tatters. The objectives of this research were to: 1) identify vulnerable bud developmental stages in hackberry and 2) determine if different commercial chloroacetamides affect severity of leaf tatters. In 2008, a preliminary spray drift experiment was conducted on mature trees from a former hackberry provenance test stand. Acetochlor (Harness), S-metolachlor (Dual II Magnum), and dimethenamid (Outlook) were applied at concentrations approximating 27%, 54%, 81%, or 108% of the recommended field rate. Three developmental stages before bud burst were present on the selected trees. Leaf tatters did not develop on the selected hackberry trees. However, symptoms were observed on neighboring, non-target hackberry trees, which had been in the leaf unfolding and expanding stages at the time of spraying. In 2009, three year old hackberry seedlings were treated with 1%, 10%, and 100% of the recommended field rate of acetochlor (Harness), S-metolachlor (Dual II Magnum), and dimethenamid (Outlook). Folded buds and two unfolding leaf developmental stages were present on seedlings. Another spray study was conducted on 32 mature hackberry trees from the provenance stand. A solution of 5608 mg a.i./L dimethenamid (Outlook) was applied to trees in the unfolding and/or expanding leaf stage. Treated trees represented four provenances. Image analysis was used to calculate seedling and mature tree leaf areas and estimate the seedling percentage of leaf tissue loss. Foliar damage was not significantly different between seedlings treated with water, 1%, or 10% of the field rate. Foliar damage was significantly different between seedlings treated with 1% or 100% of the field rate, and between seedlings treated with 10% or 100% of the field rate. Foliar damage in seedlings was not significantly different between the developmental stages. Additionally, symptoms of leaf tatters were observed on the treated mature hackberry. Future studies should focus on chloroacetamide concentrations above 10% of the recommended field rate.
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This study tested a dynamic field theory (DFT) of spatial working memory and an associated spatial precision hypothesis (SPH). Between 3 and 6 years of age, there is a qualitative shift in how children use reference axes to remember locations: 3-year-olds’ spatial recall responses are biased toward reference axes after short memory delays, whereas 6-year-olds’ responses are biased away from reference axes. According to the DFT and the SPH, quantitative improvements over development in the precision of excitatory and inhibitory working memory processes lead to this qualitative shift. Simulations of the DFT in Experiment 1 predict that improvements in precision should cause the spatial range of targets attracted toward a reference axis to narrow gradually over development, with repulsion emerging and gradually increasing until responses to most targets show biases away from the axis. Results from Experiment 2 with 3- to 5-year-olds support these predictions. Simulations of the DFT in Experiment 3 quantitatively fit the empirical results and offer insights into the neural processes underlying this developmental change.
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The relative growth and population structure of the terebellid Nicolea uspiana were investigated in the intertidal zone of a rocky shore on the south-east coast of Brazil, from May 2006 to May 2007. Eight hundred and forty-seven individuals of N. uspiana were analysed: 391 males, 163 females, and 293 immatures. Although significant differences in some morphometric parameters were found, there was no sexual dimorphism between males and females. There were differences in total length, width of segments, and length of the notopodial region between matures and immatures. The negative allometry of the total length in relation to five other parameters showed that this feature is a good measure for estimating the individual size, which was then used in the analysis of population structure. This population of N. uspiana showed a bimodal size frequency distribution, with immature and mature individuals found during the entire year. This pattern indicates continuous reproduction, with each cohort growing for at least three to four months and being responsible for two consecutive settlement peaks.
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To investigate the effects of repeated crack-cocaine inhalation on spermatogenesis of pubertal and mature Balb/c mice, ten young (Y-ex) and ten adult (A(ex)) Balb/c mice were exposed to the smoke from 5 g of crack with 57.7% of pure cocaine in an inhalation chamber, 5 days/week for 2 months. The young (Y-c) and adult (A(c)) control animals (n = 10) were kept in a specially built and controlled animal house facility. The morphologic analysis of both testes of all animals included the analysis of quantitative and qualitative histologic parameters to assess the effect of crack-cocaine on spermatogenesis and Leydig cells. Apoptosis was determined by immunolabeling with caspase-3 antibodies. Compared to the Y-c animals, Y-ex animals showed a significant reduction in the number of stage VII tubules per testis (p = 0.02), Sertoli cells (p < 0.001) and elongated spermatids (p = 0.001). Comparisons between the Y-ex and A(ex) groups identified a significant reduction in the number of Sertoli cells (p < 0.001) and round spermatids (p < 0.001) in the Y-ex group and a significant increase in apoptotic Leydig cells (p = 0.04) in the A(ex) group. The experimental results indicate that crack-cocaine smoke inhalation induced spermatogenesis disruption in chronically exposed mice, particularly in pubertal mice.
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The aim of this study was to determine and compare the fatty acid (FA) composition of colostrum and mature milk produced by nursing mothers of preterm and at-term newborns, in Florianopolis, SC, Brazil. Low contents of Eicosapentaenoic acid (EPA) (0.02%/colostrum and 0.01%/mature milk for preterm and term milk) and Docosahexaenoic acid (DHA) (colostrum group: 0.10%/preterm and 0.09%/term; mature milk: 0.05%/preterm and 0.03%/term) were determined. The comparison among the groups showed that the elaidic acid content was significantly higher (1.67%) in mature term milk. The content of rumenic acid (conjugated linoleic acid) was significantly higher in at-term colostrum compared with preterm colostrum. When considering the maturity of the milk, there was a significant increase in the percentage of this FA in the preterm group. The results show that, overall, the greatest differences observed were between the colostrums and mature milks for both groups and not between preterm and at-term mothers.
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This paper presents a survey of the insects that feed on fruits of Psittacanthus Martius (Santalales: Loranthaceae), a hemiparasitic mistletoe genus that infects trees in Brazil and other neotropical countries. The aim of the study was to identify candidate insects for biological control of Psittacanthus mistletoes. Unripe and mature fruits were collected in several localities of Cerrado, bordering South Pantanal, Southwestern Brazil, from 29 Apr 1998 to 30 Jul 2000. A total of 24,710 fruits (54 samples) of Psittacanthus acinarius infecting 15 species from 10 plant families were evaluated. Psittacanthus acinarius (Mart.) was the most abundant and frequent species of mistletoe parasitizing trees in the ecotonal Cerrado-Pantanal. From 24,710 fruits of Psittacanthus acinarius were obtained 1,812 insect larvae including 1,806 Neosilba McAlpine (Diptera: Lonchaeidae) species and 6 Thepytus echelta (Hewitson) (Lepidoptera: Lycaenidae). From these emerged 1,550 Neosilba spp. adults and 6 T. echelta. Neosilba pantanense Strikis was described from this research. Larvae of T. echelta occurred in fruits of P. acinarius parasitizing Cecropia pachystachya Trecul (Urticaceae) and Anadenanthera colubrina (Vellozo) Brenan (Fabaceae). Larvae of Neosilba caused no adverse effects on the germination of infected fruits of Psittacanthus, because they do not eat the embryo or viscin tissues. This differs from the larvae of T. echelta that interrupted the germination of seeds by feeding on those tissues. Thepytus echelta may be a promising insect for the biological control of P. acinarius in the ecotonal Cerrado-Pantanal, although its abundance and frequency were low throughout the sampling period.
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Background: Variations in maternal care are associated with neonatal stress, hormonal disturbances and reproductive injuries during adulthood. However, the effects of these variations on sex hormones and steroid receptors during ovary development remain undetermined. This study aimed to investigate whether variations in maternal care are able to influence the hormonal profile, follicular dynamics and expression of AR, ER-alpha and ER-beta in the ovaries of UCh rat offspring. Methods: Twenty-four adult UCh rats, aged 120 days, were randomly divided into two groups (UChA and UChB) and mated. Maternal care was assessed from birth (day 0) to the 10th postnatal day (PND). In adulthood, twenty adult female rats (UChA and UChB offspring; n = 10/group), aged 120 days, were euthanized by decapitation during the morning estrus. Results: UChA females (providing high maternal care) more frequently displayed the behaviors of carrying pups, as well as licking/grooming and arched back nursing cares. Also, mothers providing high care had elevated corticosterone levels. Additionally, offspring receiving low maternal care showed the highest estrous cycle duration, increased corticosterone and 17beta-estradiol levels, overexpression of receptors ER-alpha and ER-beta, increased numbers of primordial, antral and mature follicles and accentuated granulosa cell proliferation. Conclusions: Our study suggests that low maternal care alters corticosterone and 17beta-estradiol levels, disrupting the estrous cycle and folliculogenesis and differentially regulating the expression of ER-alpha and ER-beta in the ovaries of adult rats.
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The objective of this research was to assess morphogenetic and structural characteristics of tillers of guinea grass cv. Tanzania at different ages. The pastures of guinea grass were managed in six pasture conditions related to the combination of three frequencies (90, 95, and 99% light interception) and two post-grazing heights (25 and 50 cm). In these six pastures conditions, three tiller ages were evaluated (young, mature, and old). The design was of completely randomized block with three replications. Young tillers exhibited higher leaf appearance rate and leaf elongation rate and, consequently, higher final leaf length and number of live leaves than mature and old tillers, regardless of the pasture condition. On pastures managed with 90 or 95% light interception associated with a post-grazing height of 25 cm, old tillers presented longer leaf lifespan than young and mature ones. There is a progressive reduction in the vigor of growth of pastures of guinea grass cv. Tanzania with advancing tiller age.
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Nanoscience is an emerging and fast-growing field of science with the aim of manipulating nanometric objects with dimension below 100 nm. Top down approach is currently used to build these type of architectures (e.g microchips). The miniaturization process cannot proceed indefinitely due to physical and technical limitations. Those limits are focusing the interest on the bottom-up approach and construction of nano-objects starting from “nano-bricks” like atoms, molecules or nanocrystals. Unlike atoms, molecules can be “fully programmable” and represent the best choice to build up nanostructures. In the past twenty years many examples of functional nano-devices able to perform simple actions have been reported. Nanocrystals which are often considered simply nanostructured materials, can be active part in the development of those nano-devices, in combination with functional molecules. The object of this dissertation is the photophysical and photochemical investigation of nano-objects bearing molecules and semiconductor nanocrystals (QDs) as components. The first part focuses on the characterization of a bistable rotaxane. This study, in collaboration with the group of Prof. J.F. Stoddart (Northwestern University, Evanston, Illinois, USA) who made the synthesis of the compounds, shows the ability of this artificial machine to operate as bistable molecular-level memory under kinetic control. The second part concerns the study of the surface properties of luminescent semiconductor nanocrystals (QDs) and in particular the effect of acid and base on the spectroscopical properties of those nanoparticles. In this section is also reported the work carried out in the laboratory of Prof H. Mattoussi (Florida State University, Tallahassee, Florida, USA), where I developed a novel method for the surface decoration of QDs with lipoic acid-based ligands involving the photoreduction of the di-thiolane moiety.
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Die Vegetation ist die wichtigste Quelle von organischen flüchtigen Verbindungen (auf Englisch volatile organic compounds,VOCs), die einen bemerkenswerten Einfluss auf der Chemie und Physik der Atmosphäre haben. VOCs beeinflussen die oxidative Kapazität der Atmosphäre und tragen zu der Bildung und zum Wachstum von sekundären organischen Aerosolen bei, welche einerseits eine Streuung und Reflektierung der Energie verursachen und andererseits sich an der Bildung und Entwicklung von Wolken beteiligen. Ziel dieser Arbeit war die Beschreibung und der Vergleich von VOC Emissionen aus Pflanzen aus zwei verschiedenen Ökosystemen: Mediterranes Ökosystem und Tropisches Ökosystem. Für diese Aufgabe wurden gewöhnliche Pflanzen von beiden Ökosystemen untersucht. Siebzehn Pflanzenspezies aus der Mittelmeergebiet, welches bekannt ist für seine Vielfalt an VOC emittierenden Pflanzen, wurden in die Untersuchungen einbezogen. Im Gegensatz zum mediterranen Ökosystem sind nur wenig Information verfügbar über VOC Emissionen aus Blättern tropischer Baumspezies. Vor diesem Hintergrund wurden sechsundzwanzig Baumspezies aus verschiedenen Ökotypen des Amazonasbeckens (Terra firme, Várzea und Igapó) wurden auf VOC Emissionen auf Blattebene mit einem Küvetten-System untersucht. Analysen von flüchtigen organischen Verbindungen wurden online mit PTR-MS und offline mittels Sammlung auf entsprechenden Adsorbern (Kartuschen) und nachfolgender GC-FID Analyse untersucht. Die höchsten Emissionen wurden für Isoprene beobachtete, gefolgt durch Monoterpene, Methanol und Aceton. Die meisten Mittelmeer Spezies emittierten eine hohe Vielfalt an Monoterpenspezies, hingegen zeigten nur fünf tropische Pflanzenspezies eine Monoterpene mit einen sehr konservativen Emissionsprofil (α-Pinen>Limonen>Sabinen >ß-Pinen). Mittelmeerpflanzen zeigten zusätzlich Emissionen von Sesquiterpenen, während bei der Pflanzen des Amazonas Beckens keine Sesquiterpenemissionen gefunden wurden. Dieser letzte Befund könnte aber auch durch eine niedrigere Sensitivität des Messsystems während der Arbeiten im Amazonasgebiet erklärt werden. Zusätzlich zu den Isoprenoidemissionen waren Methanolemissionen als Indikator für Wachtumsvorgänge sehr verbreitet in den meisten Pflanzenspezies aus tropischen und mediterranen Gebieten. Einige Pflanzenspezies beider Ökosystemen zeigten Acetonemissionen. rnrnVOC Emissionen werde durch eine große Vielfalt an biotischen und abiotischen Faktoren wie Lichtintensität, Temperatur, CO2 und Trockenheit beeinflusst. Ein anderer, öfter übersehener Faktor, der aber sehr wichtig ist für das Amazonas Becken, ist die regelmäßige Überflutung. In dieser Untersuchung wir fanden heraus, dass am Anfang einer Wurzelanoxie, die durch die Überflutung verursacht wurde, Ethanol und Acetaldehyd emittiert werden können, vor allem in Pflanzenspezies, die schlechter an eine unzureichende Sauerstoffversorgung bei Flutung adaptiert sind, wie z.B. Vatairea guianensis. Die Spezies Hevea spruceana, welche besser an Überflutung adaptiert ist, könnte möglicherweise der gebildete Ethanol sofort remetabolisieren ohne es zu emittieren. Nach einer langen Periode einer Überflutung konnte allerdings keine Emission mehr beobachtet werden, was auf eine vollständige Adaptation mit zunehmender Dauer schließen lässt. Als Reaktion auf den ausgelösten Stress können Isoprenoidemissionen ebenfalls kurzfristig nach einigen Tage an Überflutung zunehmen, fallen dann aber dann nach einer langen Periode zusammen mit der Photosynthese, Transpiration und stomatäre Leitfähigkeit deutlich ab.rnrnPflanzen Ontogenese ist anscheinend von Bedeutung für die Qualität und Quantität von VOC Emissionen. Aus diesem Grund wurden junge und erwachsene Blätter einiger gut charakterisierten Pflanzen Spezies aus dem Mittelmeerraum auf VOC Emissionen untersucht. Standard Emissionsfaktoren von Isopren waren niedriger in jungen Blättern als in erwachsene Blätter. Hingegen wurden höhere Monoterpen- und Sesquiterpenemissionen in jungen Blätter einiger Pflanzenspezies gefunden. Dieser Befund deutet auf eine potentielle Rolle dieser VOCs als Abwehrkomponenten gegen Pflanzenfresser oder Pathogene bei jungen Blätter hin. In einigen Fällen variierte auch die Zusammensetzung der Monoterpen- und Sesquiterpenspezies bei jungen und erwachsenen Blättern. Methanolemissionen waren, wie erwartet, höher in jungen Blättern als in ausgewachsenen Blättern, was mit der Demethylierung von Pectin bei der Zellwandreifung erklärt werden kann. Diese Befunde zu Änderungen der Emissionskapazität der Vegetation können für zukünftige Modellierungen herangezogen werden. rn
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The research hypothesis of the thesis is that “an open participation in the co-creation of the services and environments, makes life easier for vulnerable groups”; assuming that the participatory and emancipatory approaches are processes of possible actions and changes aimed at facilitating people’s lives. The adoption of these approaches is put forward as the common denominator of social innovative practices that supporting inclusive processes allow a shift from a medical model to a civil and human rights approach to disability. The theoretical basis of this assumption finds support in many principles of Inclusive Education and the main focus of the hypothesis of research is on participation and emancipation as approaches aimed at facing emerging and existing problems related to inclusion. The framework of reference for the research is represented by the perspectives adopted by several international documents concerning policies and interventions to promote and support the leadership and participation of vulnerable groups. In the first part an in-depth analysis of the main academic publications on the central themes of the thesis has been carried out. After investigating the framework of reference, the analysis focuses on the main tools of participatory and emancipatory approaches, which are able to connect with the concepts of active citizenship and social innovation. In the second part two case studies concerning participatory and emancipatory approaches in the areas of concern are presented and analyzed as example of the improvement of inclusion, through the involvement and participation of persons with disability. The research has been developed using a holistic and interdisciplinary approach, aimed at providing a knowledge-base that fosters a shift from a situation of passivity and care towards a new scenario based on the person’s commitment in the elaboration of his/her own project of life.