2,086 research outputs found
Reproductive biology of winter-spring spawners of Illex argentinus (Cephalopoda: Ommastrephidae) off Southern Brazil
The reproduction and fecundity of winter-spring spawners of the shortfin squid Illex argentinus off southern Brazil (27°S-34°S) were studied in samples from bottom trawl surveys on the outer shelf and upper slope from 1986 to 1992. The mantle length-total weight relationships were for males: TW = 0.00002456 ML2.974 for females: TW = 0.00004265 ML 2.842 and pooled: TW = 0.00005376 ML 2.809. Males were heavier than females at the same ML. Fully mature squids were found from July to October. Mantle length and total weight of fully mature males ranged from 188 to 296 mm (mean 252.2 mm) and 195.5 to 611 g (mean 382.7 g) and for females from 225 to 356 mm (mean 307.4 mm) and 234 to 772 g (mean 558.4 g). Total weight was maximum at full maturity and decreased in the subsequent stages of both sexes. Mean weight and mean major axis length of ripe oocytes in the oviducts were 0.48 mg (sd= 0.10 mg) and 1.27 mm (sd= 0.08 mm), respectively. Total and oviduct mean fecundities, in thousands of oocytes larger than 0.4 mm, in ten fully mature females (294-336 mm ML) were 177.2 (93.0 to 294.3) and 118.4 (51.5 to 233.9), respectively. Spawning season in this region seems to be more protracted than in higher latitudes. Our results suggest that a northward migration could take place prior to spawning and that in winter and spring, southern Brazil may be a major spawning ground of Illex argentinus that contributes to the local and to the Uruguay and northeastern Argentina recruitment
Feeding and foraging ecology of Trindade petrels Pterodroma arminjoniana during the breeding period in the South Atlantic Ocean
Seabirds breeding in tropical environments experience high energetic demands, when foraging in an oligotrophic environment. The globally threatened Trindade petrel Pterodroma arminjoniana has its largest colony in Trindade Island (20°30′S–29°19′W) inside the oligotrophic South Atlantic Subtropical Gyre. Diet sampling methods, geolocator tracking and stable isotope analysis were used to describe its diet, compare foraging trips and distributions, and assess temporal variations in the trophic niche throughout the breeding period. Diet consisted mainly of squid and fish. The high species diversity and wide range of prey sizes consumed suggests the use of multiple foraging techniques. Stable isotope mixing models confirm that Trindade petrels rely mainly on squid throughout the breeding period. Its broad isotopic niche seems to reflect both a diverse diet and foraging range, since birds can reach up to 3335 km from the colony. Isotopic niche showed limited variation even in an 8-year interval, apparently due to oceanographic stability, although changes in the isotopic niche have demonstrated an adjustment to different conditions in different seasons. Petrels change foraging areas and prey during the breeding period: pre-incubating birds use more productive areas west of Trindade Island and obtain low trophic position prey; incubating petrels perform longer trips southward to consume prey of high trophic position; and chick-rearing petrels use areas around the island. These results demonstrate that to deal with high demand breeding in a colony surrounded by oligotrophic waters, Trindade petrels need to explore wide foraging areas and utilize a diverse diet, besides adjusting trophic niche according to breeding stage
Environmentally friendly homocoupling reaction of functionalized potassium aryl trifluoroborates salts in aqueous media
AbstractThe homocoupling reaction between potassium aryl trifluoroborates containing different functionalities promoted by a catalytic amount of Pd(OAc)2 is described. The methodology uses water as a solvent under aerobic conditions to give the corresponding biaryl compounds in good yields
Toll-like receptor 4 (TLR4) expression in human and murine pancreatic beta-cells affects cell viability and insulin homeostasis
<p>Abstract</p> <p>Background</p> <p>Toll-like receptor 4 (TLR4) is widely recognized as an essential element in the triggering of innate immunity, binding pathogen-associated molecules such as Lipopolysaccharide (LPS), and in initiating a cascade of pro-inflammatory events. Evidence for TLR4 expression in non-immune cells, including pancreatic β-cells, has been shown, but, the functional role of TLR4 in the physiology of human pancreatic β-cells is still to be clearly established. We investigated whether TLR4 is present in β-cells purified from freshly isolated human islets and confirmed the results using MIN6 mouse insulinoma cells, by analyzing the effects of TLR4 expression on cell viability and insulin homeostasis.</p> <p>Results</p> <p>CD11b positive macrophages were practically absent from isolated human islets obtained from non-diabetic brain-dead donors, and TLR4 mRNA and cell surface expression were restricted to β-cells. A significant loss of cell viability was observed in these β-cells indicating a possible relationship with TLR4 expression. Monitoring gene expression in β-cells exposed for 48h to the prototypical TLR4 ligand LPS showed a concentration-dependent increase in TLR4 and CD14 transcripts and decreased insulin content and secretion. TLR4-positive MIN6 cells were also LPS-responsive, increasing TLR4 and CD14 mRNA levels and decreasing cell viability and insulin content.</p> <p>Conclusions</p> <p>Taken together, our data indicate a novel function for TLR4 as a molecule capable of altering homeostasis of pancreatic β-cells.</p
PESQUISA NA WEB: ANÁLISE DOS CAMINHOS INVESTIGATIVOS COM MÚLTIPLOS TEXTOS
Com o advento da tecnologia, a sociedade que se configura exige do sujeito letrado conhecimentos mais complexos para enfrentar novas situações, em diversos campos da atuação humana. No âmbito escolar, apesar de contarem com diversos aparatos tecnológicos, o que se tem visto é uma educação com base na transferência de informações, suscitando um trabalho ainda nos moldes tradicionais. Por esse motivo, é viável dizer que o ensino com as tecnologias deve ser ressignificado. Nesse sentido, é crucial que o professor se aproprie de saberes que possibilitem a (re)estruturação em sua prática pedagógica. Sendo assim, pretende-se aqui apresentar um trabalho investigativo, decorrente de pesquisas na Web, envolvendo múltiplos textos, com alunos da EJA, além de análises dos caminhos percorridos pelos aprendizes, ao longo do processo. Intenta-se argumentar sobre a importância da mediação do professor e de um trabalho de ensino sistematizado, em contraposição a um trabalho espontâneo e livre
O que tapa o alagadiço?: os impactos do higienismo na qualidade urbana de Maceió/Alagoas (Brasil) a partir das intervenções no riacho Maceió
Entre o Oceano Atlântico – a Leste – e a Lagoa Mundaú, a Oeste, com um planalto intermediário ao Sul, origina-se Maceió. A origem do nome está atrelada às denominações, da língua tupi Maçayó, que significa “aquele que tapa o alagadiço”, talvez em alusão ao povoado se encontrar entre águas sofrendo influências da maré. Esta toponímia pode ter relação também com a existência do riacho Maçayó, atual riacho Maceió, que à época era um elemento de importância na paisagem urbana, e um dos responsáveis pelas características alagadiças do sítio. Até o século XIX, os resíduos urbanos eram despejados nas áreas encharcadas, comprometendo a qualidade urbana e consequentemente a ocupação desses locais. De modo que ao final do século XIX, orientações higienistas ditaram as transformações na cidade, como drenagens e aterros de toda área úmida, levando a intervenções em canais, lagoas e no próprio riacho Maceió.
Entretanto, hoje após intensas transformações o riacho tornou-se um dos principais meios de escoamento de esgoto, produzindo diversos prejuízos à urbanidade. Este artigo, portanto, utilizando-se de antigos documentos, iconografias e jornais da época, aborda os impactos na qualidade de vida em Maceió decorridos das intervenções higienistas com ênfase no riacho que pode ter dado nome a cidade.Between the Atlantic Ocean – to the East - and Mundaú Lagoon to the West, with an intermediate plateau to the South, originates Maceio. The origin of the name is linked to names of Tupi language Macayo, meaning “one who stops the marsh,” perhaps in reference to the village is suffering influences of tidal waters. This name can be related with the existence of the creek Macayo, current called Maceió, which at the time was an important element in the urban landscape, and one of those responsible for waterlogged nature of the site.
Until the nineteenth century, municipal waste were dumped in waterlogged areas, affecting the urban quality and consequently the occupation of these sites. At the end of the nineteenth century, hygienists guidelines dictated the transformations in the city, such as drainage and embankments of all wetland, leading to interventions in canals, ponds and the creek itself. However, today after intense transformations the creek has become a major means of sewage disposal, producing several damages to urbanity. This article, using documents, iconography and newspapers of the time, reflects the impacts on quality of life in Maceio elapsed Hygienists of interventions focusing on the creek that may have named the town.Eje 2: Forma y estructura urbana, organización del territorio, orientación del crecimiento.Facultad de Arquitectura y Urbanism
Domínio e expansão territorial: planos urbanos e seus impactos no riacho Maceió até 1950
A ocupação e expansão territorial só foi possível à medida que o ser humano dominou a técnica e com isso a possibilidade de transformar a natureza segundo suas necessidades. O desenvolvimento das cidades é um resultado desse domínio da técnica sobre o meio natural, especialmente a partir das ações projetuais realizadas em períodos históricos distintos e que intervêm muitas vezes drasticamente nos elementos naturais incorporados ao ambiente urbano. Dessa forma esse artigo busca investigar os planos urbanos desenvolvidos para a cidade de Maceió durante o séc. XIX até 1950 envolvendo o riacho Maceió, curso d´água que inicialmente estabeleceu limites para a ocupação urbana, e como esses planos e/ou intervenções podem ter impactado o riacho, especialmente na sua apropriação e simbologia, refletindo as relações entre o meio natural e o construído.The occupation and territorial expansion was only possible as a human being and with this technique dominated the possibility of transforming the nature according to your needs. The development of cities is a result of that mastery of technique about the natural environment, especially from the project actions carried out in different historical periods and involved many times dramatically in natural elements incorporated into the urban environment.
In this way, this article seeks to investigate the urban plans developed for the city of Maceió during the 19th century until 1950 involving the Creek Maceió, course of water that initially established limits for urban occupation, and how these plans/ intervention might have impacted the Creek, especially in its appropriation and symbology, reflecting the relationships between the natural environment and the built.Eje 2: Forma y estructura urbana, organización del territorio, orientación del crecimiento.Facultad de Arquitectura y Urbanism
O que tapa o alagadiço?: os impactos do higienismo na qualidade urbana de Maceió/Alagoas (Brasil) a partir das intervenções no riacho Maceió
Entre o Oceano Atlântico – a Leste – e a Lagoa Mundaú, a Oeste, com um planalto intermediário ao Sul, origina-se Maceió. A origem do nome está atrelada às denominações, da língua tupi Maçayó, que significa “aquele que tapa o alagadiço”, talvez em alusão ao povoado se encontrar entre águas sofrendo influências da maré. Esta toponímia pode ter relação também com a existência do riacho Maçayó, atual riacho Maceió, que à época era um elemento de importância na paisagem urbana, e um dos responsáveis pelas características alagadiças do sítio. Até o século XIX, os resíduos urbanos eram despejados nas áreas encharcadas, comprometendo a qualidade urbana e consequentemente a ocupação desses locais. De modo que ao final do século XIX, orientações higienistas ditaram as transformações na cidade, como drenagens e aterros de toda área úmida, levando a intervenções em canais, lagoas e no próprio riacho Maceió.
Entretanto, hoje após intensas transformações o riacho tornou-se um dos principais meios de escoamento de esgoto, produzindo diversos prejuízos à urbanidade. Este artigo, portanto, utilizando-se de antigos documentos, iconografias e jornais da época, aborda os impactos na qualidade de vida em Maceió decorridos das intervenções higienistas com ênfase no riacho que pode ter dado nome a cidade.Between the Atlantic Ocean – to the East - and Mundaú Lagoon to the West, with an intermediate plateau to the South, originates Maceio. The origin of the name is linked to names of Tupi language Macayo, meaning “one who stops the marsh,” perhaps in reference to the village is suffering influences of tidal waters. This name can be related with the existence of the creek Macayo, current called Maceió, which at the time was an important element in the urban landscape, and one of those responsible for waterlogged nature of the site.
Until the nineteenth century, municipal waste were dumped in waterlogged areas, affecting the urban quality and consequently the occupation of these sites. At the end of the nineteenth century, hygienists guidelines dictated the transformations in the city, such as drainage and embankments of all wetland, leading to interventions in canals, ponds and the creek itself. However, today after intense transformations the creek has become a major means of sewage disposal, producing several damages to urbanity. This article, using documents, iconography and newspapers of the time, reflects the impacts on quality of life in Maceio elapsed Hygienists of interventions focusing on the creek that may have named the town.Eje 2: Forma y estructura urbana, organización del territorio, orientación del crecimiento.Facultad de Arquitectura y Urbanism
Domínio e expansão territorial: planos urbanos e seus impactos no riacho Maceió até 1950
A ocupação e expansão territorial só foi possível à medida que o ser humano dominou a técnica e com isso a possibilidade de transformar a natureza segundo suas necessidades. O desenvolvimento das cidades é um resultado desse domínio da técnica sobre o meio natural, especialmente a partir das ações projetuais realizadas em períodos históricos distintos e que intervêm muitas vezes drasticamente nos elementos naturais incorporados ao ambiente urbano. Dessa forma esse artigo busca investigar os planos urbanos desenvolvidos para a cidade de Maceió durante o séc. XIX até 1950 envolvendo o riacho Maceió, curso d´água que inicialmente estabeleceu limites para a ocupação urbana, e como esses planos e/ou intervenções podem ter impactado o riacho, especialmente na sua apropriação e simbologia, refletindo as relações entre o meio natural e o construído.The occupation and territorial expansion was only possible as a human being and with this technique dominated the possibility of transforming the nature according to your needs. The development of cities is a result of that mastery of technique about the natural environment, especially from the project actions carried out in different historical periods and involved many times dramatically in natural elements incorporated into the urban environment.
In this way, this article seeks to investigate the urban plans developed for the city of Maceió during the 19th century until 1950 involving the Creek Maceió, course of water that initially established limits for urban occupation, and how these plans/ intervention might have impacted the Creek, especially in its appropriation and symbology, reflecting the relationships between the natural environment and the built.Eje 2: Forma y estructura urbana, organización del territorio, orientación del crecimiento.Facultad de Arquitectura y Urbanism
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