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Perspectivas dos efeitos do aumento do CO2 atmosférico sobre os organismos construtores do Atol das Rocas- RNPINHEIRO, Barbara Ramos 30 August 2016 (has links)
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Previous issue date: 2016-08-30 / O aumento da pressão parcial de dióxido de carbono (pCO2) na atmosfera, que passou de uma
média de 280ppm antes da revolução industrial para acima de 400ppm nos dias atuais, é um
dos principais responsáveis por uma série de mudanças globais. Entre elas, a elevação da
temperatura superficial da água do mar (TSM), a elevação do nível do mar, e a acidificação
oceânica (AO). Os ambientes recifais têm sido apontados como os mais vulneráveis a estas
mudanças. Efeitos da elevação da pCO2 sob ambientes recifais no Atlântico Sul, são escassos
e na sua maioria reportam apenas efeitos da elevação da TSM e eventos de branqueamento. O
Atol das Rocas é a primeira Reserva Biológica marinha do Brasil e foi escolhido neste estudo
por ser um exemplo de recife biogênico, oceânico e praticamente livre de impactos como
sobrepesca, poluição, e turismo desordenado. Desta forma, o objetivo do presente estudo foi
avaliar os efeitos da elevação da pCO2 atmosférica sob os organismos construtores do atol para
estabelecer um ponto de referência para futuras comparações, devido a sua vulnerabilidade a
estes processos. A pesquisa foi dividida em três etapas, sendo essas a caracterização, a avaliação
do estado e a experimentação dos prováveis efeitos da acidificação nos organismos calcários.
Inicialmente são apresentados dados sobre a cobertura bentônica e a sua interação com os
parâmetros abióticos (temperatura, salinidade, disponibilidade de nutrientes dissolvidos, pH e
alcalinidade total). Foi observada dominância de macro e tufos de algas em locais com maior
disponibilidade de nutrientes dissolvidos, indicando que maiores concentrações de nutrientes
inorgânicos na água do mar contribuem para a distribuição dos organismos no atol. E, além
disso, ambientes com alta frequência de organismos carbonáticos foram associados com uma
diminuição da concentração de alcalinidade. Em seguida, dados foram obtidos sobre
reprodução, crescimento e distribuição de frequência da população da espécie de coral
dominante nas piscinas do atol (Siderastrea stellata). Foi observado um evento de planulação
e o crescimento inicial dos pólipos primários, os quais, após 3 meses mostraram uma média de
diâmetro de 1,49±0,45 mm, variando entre 0,9 e 2,28 mm e 14,70% de taxa de mortalidade. A
média da taxa de extensão anual das colônias adultas foi de 6,8 ± 0,7 mm. ano-1. Colônias com
4,1 a 10 cm de diâmetro também foram frequentes no atol (48,1±14,5%). A população de S.
stellata no atol mostra-se com um alto potencial de manutenção e recuperação, embora tenha
sido observado uma baixa taxa de recrutamento. Na outra etapa do estudo se fez uma
caracterização do sistema carbonato no atol, avaliando a influência do metabolismo dos
organismos sob as variações espaço-temporais observadas. Os resultados indicaram uma grande
disponibilidade de carbonato dissolvido nas piscinas do atol. Os índices de saturação de
aragonita não só suprem as necessidades metabólicas dos organismos, como estão acima dos
observados para outros ambientes recifais. Desta forma, é possível que a intensa atividade
biológica no atol das rocas possa servir como um tampão adicional para o equilíbrio do pH e
mitigar alguns dos efeitos da acidificação oceânica localmente. Por fim, foi realizado um
experimento com espécies que ocorrem no atol, o coral scleractíneo Porites astreoides e o
zoantídeo Palythoa caribaeorum. Foram avaliadas as respostas fisiológicas (crescimento,
respiração, fotossíntese, lipídios totais e clorofila a) desses organismos mediante condições de
estresse térmico e acidificação. P. astreoides sofreu influência do aquecimento e da acidificação
em todas as taxas metabólicas avaliadas, enquanto o P. caribaeorum teve um menor, ou nenhum
impacto no seu metabolismo. / The increase in carbon dioxide partial pressure (pCO2) in the atmosphere, which rose from an
average of 280 ppm before pre-industrial times to over 400 ppm today, it is one of the main
responsible for a series of global changes. Among them, increasing sea surface temperature
(SST), sea level rise and ocean acidification (OA). Coral reefs have been identified as the most
vulnerable ecosystem to these changes. Investigations about the effects of elevated
anthropogenic pCO2 on coral reef environments in the South Atlantic are scarce and mostly
only effects of the increase of SST and bleaching events were reported. Rocas Atoll is the first
Marine Biological Reserve in Brazil and was chosen in this study because it is an example of a
oceanic biogenic reef, and virtually free from impacts such as overfishing, pollution, and
unregulated tourism. Thus, the aim of this study was to evaluate the effects of increased
atmospheric pCO2 on the atoll building organisms to establish a benchmark for future
comparisons, because of their vulnerability to these processes. Initially are presented data on
the benthic cover and its interaction with the abiotic parameters (temperature, salinity,
availability of dissolved nutrients, pH and total alkalinity). It was observed a dominance of
macro and tuff algae in places with higher availability of dissolved nutrients, indicating that
higher concentrations of inorganic nutrients in seawater contribute to the spatial distribution of
organisms on the atoll. And besides, environments with high frequency of carbonate organisms
were associated with a decrease of alkalinity. Then, data were obtained on reproduction, growth
and frequency distribution of the population of the dominant coral species in the atoll pools
(Siderastrea stellata). A planulation event was observed and initial growth of primary polyps
which, after 3 months showed 1.49 ± 0.45 mm average diameter ranging between 0.9 and 2.28
mm and 14.70% mortality rate. The average annual extension rate of adult colonies was 6.8 ±
0.7 mm. year-1. Colonies with 4.1 to 10 cm diameter were also common in the atoll (48.1 ±
14.5%). The population of S. stellata in the atoll shows a high potential for maintenance and
recovery, although it was observed a low recruitment rate. In another stage of the study, a
characterization of the carbonate system of the atoll was made, in order to assess the influence
of the metabolism of organisms under spatio-temporal variations. The results indicated a large
availability of dissolved carbonate in the atoll pools. The aragonite saturation rates not only
supply the metabolic demands of the corals, but are above those observed for other coral reef
environments. Thus, it is possible that the intense biological activity of the Rocas Atoll can
serve as an additional buffer for the pH equilibrium and locally mitigate some of the effects of
ocean acidification. Finally, an experiment was conducted with species that occur in the atoll,
the scleractinian coral Porites astreoides and the zoanthid Palythoa caribaeorum. The
physiological responses of these organisms were evaluated (growth, respiration,
photosynthesis, total lipids and chlorophyll a) under conditions of heat stress and acidification.
P. astreoides was influenced by warmer temperatures and acidification in all measured
metabolic rates while P. caribaeorum showed a minor or no impact on your metabolism.
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Avaliação dos efeitos da vitamina c em ovinos submetidos à dieta calculogênica / Evaluation of the effects of vitamin c in sheep submitted to calculogenic dietMACIEL, Thiago Arcoverde 27 February 2015 (has links)
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Previous issue date: 2015-02-27 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Urolithiasis is a metabolic disease of complex and multifactorial etiology, characterized by uroliths formation in the urinary system. It becomes clinically important when obstruction occurs, with little chance of reversal, and prevention is the best option for maintaining the integrity of the reproductive capacity. For this, one must know the biochemical profile of animals and fix the possible factors that may be related to the formation of uroliths. Morphometric study in turn, enables the comparative observation and description of changes and can therefore be used as a method of diagnostic. Urinary acidification is cited as an efficient alternative for the prevention, so vitamin C was used. In this study, 20 healthy sheep, male (not neutered), Santa Ines breed, aged approximately 90 days, were divided into three groups (G1 n=7 - calculogenic diet without vitamin C, G2 n=7 - calculogenic diet with vitamin C and G3 n=6 - control). To analyze the biochemical profiles groups 1 and 2 were compared and the morphometric analysis the three groups were compared. Animals were examined weekly, allowing direct observation of clinical signs, such as prostration/restlessness, penile exposure, abdomen kicking, urethral process congestion, among others. Analysis of biochemical profiles of urine and serum revealed hyperproteinemia (8.99g/dL) and proteinuria (43.82g/dL) in 57.14% aciduria (G1) and 71.43% (G2) and the presence of erythrocytes, leukocytes, bacteria and sperm to the urinary sediment. There was an important increase of phosphorus and magnesium e there was a substantial decrease of calcium which was present in 50% of uroliths samples analyzed. At the end of the experimental time animals were slaughtered and necropsy of them was followed by morphometry of the organs of the urinary system. Necrosis of urethral process and bladder with extensive bleeding area were observed during the necropsy procedure. The width of the kidneys and ureters were higher in G2, which may have contributed to lower retention of uroliths on this site. / Urolitíase é uma doença metabólica de etiologia complexa e multifatorial, caracterizada pela formação de urólitos no sistema urinário. Torna-se clinicamente importante quando ocorre obstrução, havendo poucas chances de reversão do quadro, sendo a prevenção a melhor opção para manutenção da capacidade reprodutiva. Para isso, deve-se conhecer o perfil bioquímico dos animais e corrigir os possíveis fatores que estão relacionados à formação dos urólitos. O estudo morfométrico por sua vez, possibilita a observação comparativa e descrição de alterações podendo ser empregado como método de auxílio diagnóstico. A acidificação urinária é citada como alternativa eficiente para a prevenção, por isso a vitamina C foi utilizada. Nesse estudo foram utilizados 20 ovinos hígidos, da raça Santa Inês, machos (não castrados), com idade aproximada de 90 dias, distribuídos em três grupos (G1 n=7 – dieta calculogênica sem vitamina C, G2 n=7 – dieta calculogênica com vitamina C e G3 n=6 – controle). Para análise dos perfis bioquímicos foram confrontados os grupos 1 e 2, e para a morfometria foram comparados os três grupos. Os animais foram examinados semanalmente, permitindo a imediata observação dos sinais clínicos, como prostração/inquietação, exposição peniana, escoiceamento do abdômen, congestão de processo uretral. A bioquímica sérica e urinária revelou hiperproteinemia (8,99g/dL) e proteinúria (4,38g/dL), acidúria em 57,14% (G1) e 71,43% (G2) e presença de hemácias, leucócitos, bactérias e espermatozóides ao exame do sedimento urinário. Houve elevação expressiva do fósforo e do magnésio e diminuição substancial do cálcio que esteve presente em 50% das amostras de urólitos analisadas. Ao término do experimento foi realizado o abate e necropsia dos animais seguindo-se a morfometria dos órgãos do sistema urinário. Necrose de processo uretral e bexiga repleta com extensa área de hemorragia foram observados durante necropsia. Os rins e ureteres apresentaram valores morfométricos distintos entre os grupos, sendo maiores no G2, o que pode ter contribuído para uma menor retenção de cálculos neste local.
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Acidification trends in Swedish lakes : an assessment of past water chemistry conditions using lake sedimentsKorsman, Tom January 1993 (has links)
This thesis presents temporal perspectives of lake acidification in Sweden. Sediment records have been used to study timing, trends and causes of acidification, and two different techniques for assessing past lake-water acidity are presented. A new technique for pH prediction, based on near-infrared (NIR) spectroscopy of surface sediments, is developed. This study shows that there is a pH related fraction of lake sediments that can be recorded by NIR analysis. Relationships between NIR spectra of surface sediment samples and measured lake-water pH values, and between NIR spectra of sediment cores and historical pH values inferred by diatom analysis, are modelled by partial least squares regression. The prediction errors of the models are comparable to those obtained by modelling of diatom and lake-water pH data. By further development NIR spectroscopy can become useful for inferring past pH, as well as several other lake-water parameters, from sediment cores. Diatom-based predictive models, using multivariate calibration methods, are developed for inferences of lake-water pH, alkalinity and colour. These models are used to provide a regional assessment of recent lake acidification in the provinces of Västerbotten and Norrbotten, northern Sweden. The study shows that a pH decline has occurred in some southeastern lakes, but that most of the lakes have not faced significant changes in lake-water pH, alkalinity and colour. The inferred water chemistiy changes are discussed in relation to atmospheric deposition and land-use. In a study of eight acid-sensitive Swedish boreal-forest lakes a past-analogue approach is used to test whether contemporary expansion of conifers could cause lake acidification. Water chemistry changes associated with the natural pre-historic colonization and expansion of spruce in Sweden (≈3000 years B.P.), at times of background atmospheric acidity, are inferred to evaluate the acidification ability of spruce per se on surface waters. This study shows that under natural, unpolluted conditions spruce colonization and expansion did not cause lake acidification. In a synthesis of palaeolimnological acidification research in Sweden a general model for pH- development for acid clear-water lakes in southern Sweden is presented. The pH-development from the last deglaciation to present time can be divided into four different periods; (i) a natural long-term acidification period (12000 B.P. - 2300 B.P., or later), with a gradual decrease in pH resulting from declining fluxes of base cations from catchment soils; (ii) a human induced alkalization period (2300 B.P. - 1900 A.D.), with a pH increase due to human activities in the catchments; (iii) the recent acidification period (about 1900 A.D. - present), when pH decreased towards 4.5 due to acid deposition and possibly ceased land-use; and (iv) the liming period (1970s - present), when pH often increases to values above 7 following lime treatment to counteract acidification. The implications of these past pH changes for the concept of contemporary lake acidification and for liming policy are outlined. / digitalisering@umu
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The effect of coarse woody debris on site productivity of some forest sites in southwestern British ColumbiaKayahara, Gordon John 11 1900 (has links)
I explored the importance of decaying wood to survival and growth of trees in south coastal
British Columbia, and the effect of decaying wood on the intensity of podzolization on mesic
sites.
A field pot study was carried out in both high light and low light conditions using woody and
non-woody forest floor materials. After two growing seasons, Pseudotsuga menziesii, Tsuga
heterophylla, and Abies amabilis seedlings growing in clearcuts had greater survival and growth
in the non-woody substrate; however, in the understory, the effect was much less. The
proliferation of western hemlock roots was used as an indicator of the value of decaying wood to
trees. In both greenhouse trials (using seed sown on a series of planting pots with each half filled
with either a woody substrate or a non-woody substrate), and in field sampling of woody and
non-woody substrates in mature stands, the non-woody substrate had a larger density of fine and
very fine roots compared to the woody substrates or mineral soil.
Ten litres of concentrated solutions of non-woody humus substrate and woody substrates
were leached through soil columns. Both the non-woody and woody solutions had similar mean
pH but significantly different chemical properties. The non-woody solution leachate had greater
net average output of dissolved organic C, Fe, and Mn. The mineral soil treated with the nonwoody
solution had significantly greater concentrations of total N and pyrophosphate-extractable
Fe. In the field, forest floor and soil samples were compared between pedons having large
accumulation of decaying wood and pedons with non-woody humus forms. Despite large and
significant differences in chemical properties between the two substrates, there were generally no
significant differences between the chemical properties of the soils directly under these
substrates. In most cases, the results of (3-analyses showed that the means were not
pedologically different. Additionally, 18 pairs of zero tension plate lysimeters were installed
under the two substrates. The lysimeter solutions showed no significant differences.
I concluded that coarse woody debris appears not to have either a positive effect of increased
productivity of trees or a negative effect of increased intensity of podzolization. / Forestry, Faculty of / Graduate
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INFLUÊNCIA DO pH DA ÁGUA NA GÊNESE DE LESÕES DO TRATO DIGESTÓRIO POR INTOXICAÇÃO COM CÁDMIO EM RATOS / INFLUENCE OF THE pH OF WATER IN THE INITIATION OF DIGESTIVE TRACT INJURY IN CADMIUM POISONING IN RATSGonçalves Filho, Mozart Alves 26 June 2015 (has links)
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Previous issue date: 2015-06-26 / Cancer is a universal disease, with high mortality rates in some cases. It is the second leading cause of death in the Western world, and go to the first place around the year 2020. Cancer has genetic and environmental causes, one of them the ingestion of heavy metals such as cadmium. There are few studies evaluating the gastrointestinal toxicity of cadmium. There is no consensus in the literature on the treatment of cadmium toxicity. We need simple methods to avoid its effects. Objective: The objective of this study was to evaluate the lesions caused by cadmium poisoning in the digestive tract and the possible effect of the drinking water pH in the initiation of these lesions. Methods: For this study, 90 male Wistar rats were used, divided into 6 groups: A - 15 rats that received 400 mg / L cadmium chloride (CdCl2) in drinking water at a neutral pH of 7.0; B - 15 rats that received CdCl2 (400 mg / L) in drinking water at an acidic pH of 5.0; C - 15 rats that received CdCl2 (400 mg / L) in drinking water at a basic pH of 8.0; D - 15 rats that received water at an acidic pH of 5.0; E - 15 rats that received water at a basic pH of 8.0; and F - 15 rats that received water at a neutral pH of 7.0. All animals were euthanized after 6 months. Fragments of the esophagus, stomach, small intestine and large intestine of each rat were removed for microscopic analysis. Results: There were microscopic changes neither in the esophagus nor in the small and large intestine. Only cadmium exposed animals showed mild dysplasia of the gastric mucosa (p= 0.012), regardless of the pH (p> 0.05). Conclusion: The cadmium led to the formation of dysplastic lesions in the gastric glandular epithelium, regardless of water pH. / Câncer é uma doença universal, com taxa de mortalidade elevada em alguns casos. É a segunda causa de morte no mundo ocidental, e passará para primeiro lugar por volta do ano de 2020. Tem causas genéticas e ambientais, sendo uma delas a ingestão de metal pesado, como cádmio. Há poucos estudos avaliando a toxicidade gastrointestinal do cádmio. Não há consenso na literatura sobre o tratamento da toxicidade por cádmio. Há necessidade de métodos simples de evitar seus efeitos. Objetivo: O objetivo deste estudo foi avaliar as lesões causadas por intoxicação por cádmio no aparelho digestório e os possíveis efeitos do pH da água na gênese destas lesões. Material e métodos: Para este estudo, foram utilizados 90 ratos Wistar, machos. Os animais foram distribuídos em 6 grupos (n=15): A solução de cloreto de cádmio (400mg/L) na água de beber com pH neutro (pH 7,0); B solução de cloreto de cádmio (400mg/L) na água de beber com pH ácido (pH 5,0); C solução de cloreto de cádmio (400mg/L) na água com pH básico (pH 8,0). D água de beber com pH ácido (pH 5,0); E água de beber com pH básico (pH 8,0); F água com pH neutro (pH 7,0). Animais de todos os grupos foram eutanasiados após 6 meses. Foram retirados fragmentos do esôfago, estômago, intestino delgado e intestino grosso de cada rato para análise microscópica. Resultados: Não foram observadas alterações microscópicas no esôfago nem no intestino delgado e grosso. Somente animais expostos ao cádmio apresentaram displasia leve da mucosa gástrica (p= 0,012), porém sem diferença com relação aos diferentes pH da água (p>0,05). Conclusão: O cádmio levou a formação de lesões displásicas no epitélio glandular gástrico, independente do pH da água.
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INFLUÊNCIA DO pH DA ÁGUA NA GÊNESE DE LESÕES DO TRATO DIGESTÓRIO POR INTOXICAÇÃO COM CÁDMIO EM RATOS / INFLUENCE OF THE pH OF WATER IN THE INITIATION OF DIGESTIVE TRACT INJURY IN CADMIUM POISONING IN RATSGonçalves Filho, Mozart Alves 26 June 2015 (has links)
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Previous issue date: 2015-06-26 / Cancer is a universal disease, with high mortality rates in some cases. It is the second leading cause of death in the Western world, and go to the first place around the year 2020. Cancer has genetic and environmental causes, one of them the ingestion of heavy metals such as cadmium. There are few studies evaluating the gastrointestinal toxicity of cadmium. There is no consensus in the literature on the treatment of cadmium toxicity. We need simple methods to avoid its effects. Objective: The objective of this study was to evaluate the lesions caused by cadmium poisoning in the digestive tract and the possible effect of the drinking water pH in the initiation of these lesions. Methods: For this study, 90 male Wistar rats were used, divided into 6 groups: A - 15 rats that received 400 mg / L cadmium chloride (CdCl2) in drinking water at a neutral pH of 7.0; B - 15 rats that received CdCl2 (400 mg / L) in drinking water at an acidic pH of 5.0; C - 15 rats that received CdCl2 (400 mg / L) in drinking water at a basic pH of 8.0; D - 15 rats that received water at an acidic pH of 5.0; E - 15 rats that received water at a basic pH of 8.0; and F - 15 rats that received water at a neutral pH of 7.0. All animals were euthanized after 6 months. Fragments of the esophagus, stomach, small intestine and large intestine of each rat were removed for microscopic analysis. Results: There were microscopic changes neither in the esophagus nor in the small and large intestine. Only cadmium exposed animals showed mild dysplasia of the gastric mucosa (p= 0.012), regardless of the pH (p> 0.05). Conclusion: The cadmium led to the formation of dysplastic lesions in the gastric glandular epithelium, regardless of water pH. / Câncer é uma doença universal, com taxa de mortalidade elevada em alguns casos. É a segunda causa de morte no mundo ocidental, e passará para primeiro lugar por volta do ano de 2020. Tem causas genéticas e ambientais, sendo uma delas a ingestão de metal pesado, como cádmio. Há poucos estudos avaliando a toxicidade gastrointestinal do cádmio. Não há consenso na literatura sobre o tratamento da toxicidade por cádmio. Há necessidade de métodos simples de evitar seus efeitos. Objetivo: O objetivo deste estudo foi avaliar as lesões causadas por intoxicação por cádmio no aparelho digestório e os possíveis efeitos do pH da água na gênese destas lesões. Material e métodos: Para este estudo, foram utilizados 90 ratos Wistar, machos. Os animais foram distribuídos em 6 grupos (n=15): A solução de cloreto de cádmio (400mg/L) na água de beber com pH neutro (pH 7,0); B solução de cloreto de cádmio (400mg/L) na água de beber com pH ácido (pH 5,0); C solução de cloreto de cádmio (400mg/L) na água com pH básico (pH 8,0). D água de beber com pH ácido (pH 5,0); E água de beber com pH básico (pH 8,0); F água com pH neutro (pH 7,0). Animais de todos os grupos foram eutanasiados após 6 meses. Foram retirados fragmentos do esôfago, estômago, intestino delgado e intestino grosso de cada rato para análise microscópica. Resultados: Não foram observadas alterações microscópicas no esôfago nem no intestino delgado e grosso. Somente animais expostos ao cádmio apresentaram displasia leve da mucosa gástrica (p= 0,012), porém sem diferença com relação aos diferentes pH da água (p>0,05). Conclusão: O cádmio levou a formação de lesões displásicas no epitélio glandular gástrico, independente do pH da água.
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Utilização do palmito basal de pupunha em alternativa ao palmito foliar, visando aumentar o aproveitamento da palmeira Bactris gasipaes / Use of the basal palm of peach palm in alternative to the foliaceous palm, to increase the use of the palm tree Bactris gasipaesPaula Porrelli Moreira da Silva 02 September 2008 (has links)
O palmito pode ser obtido a partir de várias espécies de palmeiras. Devido à alta taxa de exploração das palmeiras do gênero Euterpe e ao seu baixo poder de regeneração, no mercado consumidor há falta de produto de boa qualidade. Palmeiras mais precoces e que produzam bom palmito têm sido pesquisadas, uma delas é a pupunha (Bactris gasipaes), nativa da Amazônia que apresenta características de precocidade, rusticidade e perfilhamento, com palmito de ótima qualidade, diferindo dos demais pelo sabor adocicado e a coloração amarelada. O seu cultivo pode ser feito em grande parte do território brasileiro. A porção comestível do palmito de pupunha é dividida em três partes: a basal ou caulinar (coração), a apical, e a central ou foliar (creme ou tolete). O comércio de palmito privilegia a parte central da palmeira, vendendo o palmito basal como subproduto. O presente estudo tem como objetivo demonstrar a equivalência da qualidade do palmito basal e do foliar de pupunha, priorizando-se o tratamento adicional com ácido acético, que mascara o seu sabor adocicado, comparado com o ácido cítrico, largamente utilizado nas indústrias. As amostras de palmito de pupunha foram cultivadas em área experimental pertencente a ESALQ/USP; para o processamento foram cortadas 120 palmeiras em março de 2007. Foram analisadas características físicas, químicas, bioquímicas e sensoriais do palmito basal e foliar de pupunha em seis períodos de armazenamento (1, 15, 30, 60, 90, 120 dias). O controle das operações durante o processamento foi eficiente, pois o peso e o preenchimento dos vidros não variaram entre as unidades. Durante o período de armazenamento a coloração amarelada dos palmitos basal e foliar de pupunha se manteve constante. Embora as enzimas polifenoloxidase e peroxidase tenham sido detectadas nas análises bioquímicas, seus valores foram baixos, e como a coloração foi a mesma durante o armazenamento, considera-se que as enzimas foram inativadas. A composição centesimal das amostras (umidade, proteína, matéria graxa, fração cinza, fibras e carboidratos) indicou que ambos os produtos possuem as mesmas características, as quais se assemelham muito à da palmeira juçara. A análise sensorial não mostrou diferença significativa entre as amostras, porém as notas mais baixas foram atribuídas às conservas acidificadas com ácido acético. Com relação à freqüência de consumo, observou-se que o palmito de pupunha é pouco utilizado na alimentação humana, sendo a resposta às vezes predominante. Os resultados mostraram que o palmito basal e o foliar de pupunha têm as mesmas características físicas, químicas e sensoriais, indicando que o primeiro também pode ser comercializado como palmito de primeira qualidade; o período de armazenamento não alterou as principais características dos produtos. / The palm can be obtained from several palms trees. Besides of high rate of exploration of Euterpe palms trees and his low regeneration power, there is a lack of product in the consumer market. More precocious palms trees and which produce good palm heart have been investigated, one of them is the peach palm (Bactris gasipaes), native of Amazon region that presents characteristics of precociousness, rusticity and tillering with palm heart with good quality, differing of others for the slightly sweet taste and the yellowed coloration. His cultivation can be done in great part of the Brazilian territory. The edible portion of the palm is divided in three parts: basic one or caulinar (heart), apical and central or foliaceous (cream or thole). The commerce of palm privileges the central part of the palm tree, selling heart as by-product. The aim of this study was to demonstrate the equivalence of the quality of heart and thole of peach palm, acidified with citric acid, widely used in the industries, and with acetic acid that masks the slightly sweet taste. The samples of peach palm were cultivated in experimental area of ESALQ/USP and for the processing 120 palms trees were cut in march of 2007. Heart and thole of the palm were analysed by physical, chemical, biochemical and sensorial characteristics for six periods of storage (1, 15, 30, 60, 90, 120 days). The control of the operations on the processing was efficient, since the weight and the filling out from the glasses did not vary between the unities. During the period of storage the coloration of the tholes and hearts of palm peach was yellowed, characteristic that remained constant. Even though the enzymes polyphenol oxidase and peroxidase have appeared in the biochemical analyses, its values were low, and the coloration was the same during the storage. The centesimal composition of the samples (humidity, protein, oily matter, ash, fibers and carbohydrates) indicated heart and thole of peach palm have the same characteristics, which liken very much to that of the palm tree Euterpe edulis. The sensory analysis did not show significant difference between the samples, however the lowest notes were attributed to the pickles acidified with acetic acid. Regarding the frequency of consumption, it was noticed that the palm heart of peach palm is little used in the feeding of people, being the answer \"sometimes\" the one that had major constancy. Data showed that heart and the thole of peach palm have the same physical, chemical and sensory characteristics, indicating that the first one also can be marketed like palm heart of first quality; the period of storage did not change principal characteristics of the products.
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DISSOLUTION, OCEAN ACIDIFICATION AND BIOTIC EXTINCTIONS PRIOR TO THE CRETACEOUS/PALEOGENE (K/PG) BOUNDARY IN THE TROPICAL PACIFICDameron, Serena 17 July 2015 (has links)
The several million years preceding the Cretaceous/Paleogene (K/Pg) boundary has been the focus of many studies. Changes in ocean circulation and sea level, extinctions, and major volcanic events have all been documented for this interval. Important research questions these changes raise include the climate dynamics during the warm, but not hot, time after the decay of the Late Cretaceous greenhouse interval and the stability of ecosystems prior to the mass extinctions at the end-Cretaceous.
I document several biotic perturbations as well as changes in ocean circulation during the Maastrichtian stage of the latest Cretaceous that question whether the biosphere was being preconditioned for the end-Cretaceous extinction. The first event at Shatsky Rise in the tropical North Pacific was the brief acme of inoceramid clams at ~71 Ma, followed by their abrupt extinction during the “mid-Maastrichtian event” at 70.1 Ma. The second is an intriguing dissolution event that began ~67.8 Ma at Ocean Drilling Program Site 1209 (2387 m). The dissolution event is marked by very poor planktic foraminiferal preservation and sharply reduced calcareous plankton diversity. The shift into the dissolution interval was initially gradual, then rapid. Within the late Maastrichtian dissolution interval, the planktic/benthic (P/B) ratio is low, planktic foraminifera are highly fragmented, larger taxa are mostly absent, small taxa are relatively abundant, and planktic foraminifera and nannofossil species richness are low. The event is followed by an abrupt recovery in carbonate preservation ~300 kyr prior to the K/Pg boundary. Was the dissolution event caused by a change in deep water circulation, migration of the site out of the high productivity tropical belt, or ocean acidification associated with Deccan Traps volcanism? Our data show that changing deep water masses, coupled with reduced productivity and associated decrease in pelagic carbonate flux was responsible for the dissolution interval, while Deccan Traps volcanism may have caused surface ocean acidification ~200-kyr prior to the K/Pg mass extinction event.
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Ryby a bentos Černé Nisy a jejich kontaminace kovy v období zotavování z acidifikace / Fish and benthos of the Černá Nisa stream and their contamination by metals in the period of recovery from acidificationBurdová, Lucie January 2010 (has links)
The aims of the thesis were to compare chemistry of the Černá Nisa stream in the Jizera Mountains (Northern Bohemia, Czech Republic) at the end of the era of strong anthropogenic acidification (in the mid-1990s) and in the period of the recent intensive chemical and biological recovery from acidification, and to study the present biota of the stream. During the year 2008, physical and chemical parameters of the water were studied, the species and age composition of ichthyofauna, and the quality and quantity of macrozoobenthos - the main component of the food for fish. Special attention was paid to the content of toxic metals (Be, Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, Pb, Hg) in the water, main representatives of benthic organisms, and in selected tissues of brook charr. The comparison of the water chemistry with results from the years 1994, 1996, and 1997 showed a decrease in acidification, despite the unstable chemical climate during the seasons, and sulphate and nitrate concentrations still high. Since the mid 1990s, the stream has been inhabited by a stable population of brook charr (Salvelinus fontinalis), a non-native, highly acid-tolerant species, which is now dominating there. At present, also a stable population of a native species, common minnow (Phoxinus phoxinus), occurs in the stream....
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Společenstva půdních hlístic při různých způsobech obnovy vřesovišť / Communities of terrestrial nematodes after different approaches to heathland restorationRadochová, Petra January 2015 (has links)
Since the 20th century, the distribution of European heathlands rapidly decreased due to agricultural intensification, heavy use of artificial fertilizers or acidification. Therefore, various attempts of heathland restoration are under way in these days. Analysis of nematode community composition can be one of the tools suitable for succession evaluation. In 2011, 2013 and 2014, soil samples were collected from heathland restoration experiment (launched in 2011) where different restoration methods were applied in a 3 × 3 factorial experiment; existing heathlands were also sampled to identify the target community both in dry and wet heathland. A total of 60 samples of extracted nematodes were analysed for absolute abundance, trophic groups, and genera dominance. Various indices were calculated to describe the nematode community. We were able to proove faster development of wet heathlands towards the target community. However, because of large data variability, there was no significant difference between treatments. Development of wet and dry heathlands differed also in increased proportion of omniphagous nematodes in 2013 and predators in 2014 in dry heathlands. After three years of heathland restoration, nematode community has not yet reached parameters of the target community. Key words: Nematoda,...
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