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Chemical water quality in Selenge River Basin in Mongolia: spatial-temporal patterns and land use influenceBatbayar, Gunsmaa 09 July 2018 (has links)
No description available.
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QUALIDADE DO LEITE EM DIFERENTES SISTEMAS DE PRODUÇÃO, ANOS E ESTAÇÕES CLIMÁTICAS NO NOROESTE DO RIO GRANDE DO SUL / MILK QUALITY PRODUCED IN DIFFERENT PRODUCTION SYSTEMS, YEARS AND SEASONS AT REGION NORTHWEST RIO GRANDE DO SUL, BRAZILMilani, Marceli Pazini 25 October 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective was to evaluate the milk quality coming from Region Northwest Rio
Grande Sul, under different technology levels, from October 2007 to September 2010, at
different seasons. The variables were fat, protein, lactose, total solids, somatic cell count
(SCC) and total bacterial count (TBC) of milk. Data were analyzed using mixed model with
repeated measure data, having the effect of fixed production system, years and seasons, and
random effect dairy farm designated in each production system. The results were compared
with the standard required by Normative Instruction 51 (NI 51) of 18 September 2002
(Minisério da Agricultura, Pecuária e Abastecimento). There were significant differences
between the systems of production for fat and total bacterial count milk, with higher values in
non specialized system. All variables were influenced by season, featuring in the autumn, fat,
protein, total solids and higher TBC. The lactose content was influenced by the production
system, presenting the most specialized and smaller in the not specialized, and the season,
being higher in winter and lower in autumn. There was a high percentage of samples in
disagreement with the NI 51 to TBC and SCC, especially those belonging to dairy farm
partially and not specialized. / Foi avaliada a qualidade do leite oriundo da Mesorregião Noroeste do Rio Grande do
Sul, sob distintos níveis tecnológicos, no período de outubro de 2007 a setembro de 2010, nas
diferentes estações do ano. As variáveis analisadas foram gordura, proteína, lactose, sólidos
totais, contagem de células somáticas (CCS) e contagem bacteriana total (CBT) do leite. Os
dados foram analisados por meio de modelo misto com medida repetida no tempo, tendo
como efeito fixo os sistemas de produção, anos e estações do ano, e efeito aleatório a unidade
produtora de leite (UPL) designada em cada sistema de produção. Os resultados foram
comparados com o padrão exigido pela Instrução Normativa 51 (IN 51) de 18 de setembro de
2002 (Ministério da Agricultura, Pecuária e Abastecimento). Observou-se diferenças
significativas entre os sistemas de produção para os teores de gordura e contagem bacteriana
total do leite, com valores superiores no sistema não especializado. Todas as variáveis tiveram
influência da estação do ano, apresentando, no outono, teor de gordura, proteína, sólidos totais
maior e CBT menor. O teor de lactose foi influenciado pelo sistema de produção,
apresentando-se maior no especializado e menor no não especializado, assim como pela
estação do ano, sendo maior no inverno e menor no outono. Observou-se uma porcentagem
alta de amostras em desacordo com a IN 51, para CBT e CCS, principalmente as pertencentes
a UPL`s do sistema semi e não especializado.
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Avaliação da variação sazonal e atividade biológica dos óleos voláteis em duas espécies de Annonaceae / Evaluation of the seasonal variation and biological activity of volatile oils from two Annonaceae speciesRosilene Kinue Ito 02 October 2008 (has links)
Nesse estudo, foram avaliados os óleos voláteis de Porcelia macrocarpa (Warm) R. E. Fries e Rollinia sericea (R. E. Fries) R. E. Fries com relação a sua composição ao longo das estações anuais e sua atividade antimicrobiana e anticolinesterase. Entre os componentes majoritários foram identificados apenas sesquiterpenos em ambas as espécies, bicicloelemeno (7%), biciclogermacreno (10%), germacreno-D (15%) e espatulenol (15%) para a P. macrocarpa e, α-muurolol (5%), Z-nerolidol (6%), bicicloelemeno (7%), germacreno-D (10%), biciclogermacreno (10%), β-cariofileno (11 %) e β-elemeno (12%) para R. sericea, não apresentando variação sazonal significativa. Os testes antimicrobianos foram realizados com bactérias Gram--positivas e negativas e com fungos filamentosos e leveduriformes. Os resultados indicaram que os óleos testados apresentam um melhor potencial antifúngico do que antibacteriano quando testado na dose de 3,125 µL/mL e não apresentaram potencial para o desenvolvimento de novos fármacos para o tratamento da doença de Alzheimer. / In this study, the volatile oils from Porcelia macrocarpa(Warm) R.E.Fr. and Rollinia sericea (R.E.Fr.) R.E.Fr. were analyzed for the seasonal variation in their chemical composition and their antimicrobial and anticholinesterase activity. The major components consisted only of sesquiterpenes in both species, bicycloelemene (7%), bicyclogermacrene (10%), germacrene-D (15%) and sphatulenol (15%) to P. macrocarpa and, α-muurolol (5%), Z-nerolidol (6%), bicycloelemene (7%), germacrene-D (10%), bicyclogermacrene (10%), β-caryophyllene (11 %) e β-elemene (12%) to R. sericea and no significant seasonal variation could be detected. The antimicrobial assays were performed with Gram-positive and negative bacteria, filamentous fungi and yeasts. The results indicated that the tested oils presented a better antifungal potential than antibacterial, when done test in the dose of 3,125 µL/mL. These oils could also not be considered as potential targets for the development of new drugs for the Alzheimer\'s treatment.
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Variação sazonal da composição, densidade e biomassa da comunidade fitoplanctônica do Rio São João, Parque Nacional do Iguaçu, Paraná, Brasil / Seasonal variation in composition, density and biomass of phytoplankton community of the São João River, Iguaçu National Park, Paraná State, BrazilBortolini, Jascieli Carla 15 July 2010 (has links)
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Jascieli Carla Bortolini.pdf: 389423 bytes, checksum: 813ef8b227c3ad9ce5caa517cd4f2d42 (MD5)
Previous issue date: 2010-07-15 / Fundação Araucária / This study aimed to analyze the seasonal variation of the phytoplankton community structure in a subtropical river through composition, richness, density and biomass data in function of environmental variables. Samplings of phytoplankton and abiotic variables were carried out between August 2008 and July 2009, at three stations in longitudinal section, at the subsurface of São João River, tributary of the Iguaçu River, Paraná State, Brazil. To estimate the density we used the Utermöhl method and biomass estimation was performed using the biovolume. Abiotic variables were summarized by Principal Component Analysis (PCA) and the data density and biovolume of species by Detrended Correspondence Analysis (DCA). We identified 221 Bacillariophyceae taxa, the more representative group. The most species-rich taxa reached 40 in September 2008 at station 1. The highest values of phytoplanktonic densities were recorded on March 2009, station 1. The Chrysophyceae and Baccillariophyceae classes were dominant in density. The biovolume was generally low, not exceeding one 1 mm3.L-1 with the highest value recorded in March 2009, station 2. The seasonal variation in phytoplankton composition were due to alternation of limnological conditions, especially in relation to temperature, which caused the change in structuring phytoplankton, however, the spatial composition was very similar, due to the proximity of the stations, and also the similarity of the distribution of the community in lotic environments, due to the unidirectional flow. / Este trabalho objetivou analisar a variação sazonal da estrutura da comunidade fitoplanctônica em um rio subtropical através dos dados de composição, riqueza, densidade e biomassa em função das variáveis ambientais. As amostragens do fitoplâncton e variáveis abióticas foram realizadas entre agosto de 2008 e julho de 2009, em três estações em secção longitudinal, à subsuperfície no Rio São João, tributário do Rio Iguaçu, Parque Nacional do Iguaçu, Paraná, Brasil. Para estimar a densidade utilizou-se o método de Utermöhl e para biomassa a estimativa foi realizada através do biovolume. As variáveis abióticas foram sintetizadas através da Análise de Componentes Principais (PCA) e os dados de densidade e biovolume das espécies através da Análise de Correspondência Destendenciada (DCA). Foram identificados 221 táxons, sendo Bacillariophyceae o grupo mais representativo. A maior riqueza de espécies atingiu 40 táxons em setembro de 2008 na estação 1. Os maiores valores de densidade fitoplanctônica foram registrados em março de 2009, estação 1. As classes dominantes em densidade foram Chrysophyceae e Bacillariophyceae. O biovolume foi em geral baixo, não ultrapassando 1 mm3.L-1 sendo o maior valor registrado em março de 2009, estação 2. As variações temporais significativas na composição da comunidade fitoplanctônica ocorreram devido à alternância das condições limnológicas, principalmente em relação à temperatura, o que proporcionou a alteração na estruturação fitoplanctônica, porém, espacialmente a composição foi muito similar, devido à proximidade das estações, e também a similaridade da distribuição da comunidade em ambientes lóticos, em função do fluxo unidirecional.
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Funcionalidade e sazonalidade sobre cerrano e sobre ecótono floresta-cerrado: uma investigação com dados micrometeorológicos de energia e CO2. / Functionality and seasonality on Cerrado and ecotone Forest-Cerrado: an inquiry with micrometeorological data of energy and CO2.Rafael Nóra Tannus 22 December 2004 (has links)
Este trabalho discute a variabilidade dos fluxos de energia à superfície e de CO2 sobre uma área de Cerrado Sensu stricto no interior de São Paulo, e de uma área de ecótono Floresta-Cerrado (sazonalmente alagável) no Estado do Tocantins. Foram utilizadas medidas micrometeorológicas médias de 30 min, do clima (temperatura e umidade do ar, precipitação, velocidade do vento), dos fluxos de radiação (solar, PAR, saldo de radiação) e fluxos turbulentos de calor sensível, latente e CO2, coletadas no Cerrado durante o período de 2001 a 2003, e no ecótono durante Outubro de 2003 a Setembro de 2004. O ecótono e o Cerrado estão sob solos arenosos, homogêneos, com alta capacidade de infiltração e baixa de armazenamento. O Cerrado s.s. mostrou-se um ecossistema com forte sazonalidade da capacidade fotossintética, do Albedo-PAR e dos fluxos atmosféricos de CO2. Há uma fase de sumidouro e outra de fonte de CO2, corroborando os dados da literatura. Na escala da variabilidade interanual, as variações dos estados funcionais do Cerrado, como sumidouro ou fonte de CO2, foram fortemente dependentes das variações da precipitação e da temperatura mínima. No ecótono Floresta-Cerrado, a fase de inundação induz à uma diminuição gradual da respiração do sistema e da produtividade primária. A diminuição na produtividade ocorre com um atraso de ~45 dias, que poderia ser um tempo de assimilação e tolerância do sistema ao estresse induzido por anóxia. A redução da respiração do ecossistema ocorre ao passo que no regime alagado as perdas de CO2 ocorrem por evasão da superfície de água livre, um processo que aparentemente tem uma fonte de emissão menor que os processos de respiração do solo em condições secas. Durante a maior parte da inundação o ecótono continua a manter-se como um sumidouro de CO2 atmosférico durante, ao menos, 3 meses. O parâmetro RUE do ecótono foi cerca de 5 vezes maior do que o do Cerrado. A diferença de eficiência se deve possivelmente ao maior índice de área foliar das formações florestais da transição Floresta-Cerrado. A funcionalidade é controlada por fatores ambientais de maior escala que as locais. No caso do Cerrado s.s. há uma forte dependência do regime de chuvas e da temperatura mínima. No caso do ecótono Floresta-Cerrado, a suscetibilidade parece ser uma função do tempo de inundação. / This work discusses the energy and CO2 flux variability over a Cerrado Sensu stricto, in São Paulo state, Brazil, and over a seasonally inundated Forest-Cerrado ecotone in Tocantins state, Brazil. Micrometeorological measurements (30 minute average) of weather (temperature, relative humidity, precipitation and wind speed), radiation fluxes (solar radiation, PAR and net radiation), and CO2, latent and sensible heat turbulent fluxes were made for the Cerrado from 2001 to 2003. Measurements for the ecotone were made from October 2003 to September 2004. Both environments have sandy, homogeneous soils, with high infiltration capacity and low water storage. Cerrado s.s. showed strong seasonality for photosynthetic capacity, Albedo-PAR and CO2 atmospheric fluxes. As seen in other works, the Cerrado has both a CO2 sink and a CO2 source phase. These are strongly dependent on the precipitation and minimal temperature. Inundation of the Forest-Cerrado ecotone results in a gradual decrease in the systems respiration and primary productivity. A lag of approximately 45 days is seen in the primary productivity reduction. This could represent the systems resistance and tolerance due to anoxia stress. Ecosystem respiration in the inundated period is lower than in the dry period, apparently due to the lower CO2 outflux from the free water surface, in comparison with the CO2 flux from the soil. During most of the inundation period, the ecotone acts as a sink for CO2, for at least 3 months. The RUE for the ecotone was proximately 5 times higher than the Cerrado. This is probably due to the higher leaf area index of the forest area in the ecotone. The functionality of both biomes is controlled by larger scale environmental factors, as opposed to local factors. The Cerrado s.s. has a strong dependence precipitation and minimal temperature. The Forest-Cerrado ecotone shows a high dependence on the length of the inundated period.
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Keuhkoahtaumataudin sairaalahoito Suomessa: hoitoajan pituus ja sen yhteys ennusteeseenKinnunen, T. (Tuija) 03 April 2007 (has links)
Abstract
The purpose of this work was to determine on the basis of the national hospital discharge register and cause-of-death statistics the extent of the hospital treatment required for chronic obstructive pulmonary disease (COPD) in Finland over the period 1972–2001, i.e. the use made of hospital services, factors affecting the length of stay in hospital and the correlation of length of stay with the prognosis. Different intervals within this period were taken for study according to the themes of the individual papers.
The results suggest that the length of stay in hospital varies both geographically and seasonally in Finland, the shortest times being recorded in Northern Finland in summer. The main explanations for this would appear to lie in regional differences in health care resources and treatment practises and in climatic variations.
The mean length of stay in hospital in the total material in 1987–1998 was nine days. The longest periods applied to cases with concurrent pneumonia or a cerebrovascular disorder.
The duration of treatment for the exacerbation stage of COPD decreased by two days between 1993 and 2001, with the longest periods of treatment observed in the case of elderly women. One week of treatment with current modalities may be regarded as optimal, as this was associated with the longest interval before the next exacerbation, just over six months.
About 3% of all emergency admissions ended in death, most commonly on a Friday in winter or spring. Patients admitted at a weekend died within the first 24 hours more frequently than did those admitted on a weekday.
The mean duration of treatment and frequency of hospitalization increased towards the terminal stage. About one fourth of the patients had died within a year of the first admission for COPD and about a half within five years.
Hospital treatment for COPD intensified in Finland during the 1990s as the numbers of hospital beds decreased. Treatment times became shorter and deaths in hospital during exacerbation became less frequent. It will be necessary from now onwards, however, to anticipate the ageing of the population and to develop treatment modalities to replace hospitalization, in order to reduce the costs accruing from this disease. Early diagnosis and outpatient rehabilitation should be developed, and special attention should be paid to appropriate treatment at the terminal stage. / Tiivistelmä
Tutkimuksen tarkoituksena oli selvittää valtakunnallisen hoitoilmoitusrekisterin ja kuolemansyytilaston avulla keuhkoahtaumataudista (KAT) aiheutunutta sairaalahoitoa Suomessa 1972–2001: sairaalapalvelujen käyttöä, hoitojakson pituuteen vaikuttavia tekijöitä sekä hoitoajan yhteyttä ennusteeseen. Lähdeaineistosta valittiin erilaisia ajanjaksoja tutkimusasetelman mukaan.
Tulokset viittaavat siihen, että hoitoajan pituus vaihtelee Suomessa maantieteellisesti ja vuodenaikojen mukaan: lyhyin hoitoaika on Pohjois-Suomessa kesällä. Ilmiötä selittänevät pääosin terveydenhuollon resurssien ja hoitokäytäntöjen alueelliset erot sekä ilmasto-olosuhteiden vaihtelu.
Vuosina 1987–1998 keskimääräinen hoitoaika koko aineistossa oli yhdeksän vuorokautta. Jos potilaalla oli samanaikaisina sairauksina keuhkokuume tai aivoverenkiertohäiriö, nämä johtivat pisimpiin hoitoaikoihin.
KAT:n pahenemisvaiheen hoitoaika lyheni kaksi vuorokautta vuodesta 1993 vuoteen 2001. Iäkkäitten naisten hoitoajat olivat pisimmät. Viikon pituinen hoitoaika nykyisillä hoitomuodoilla oli optimaalinen, sillä tällöin aika seuraavan pahenemisvaiheen hoitojakson alkuun oli pisin: vähän yli puoli vuotta.
Kaikista päivystyshoitojaksoista potilaan kuolemaan päättyi kolmisen prosenttia. Yleisimmin tällainen hoitojakso päättyi potilaan kuolemaan perjantaisin ja todennäköisimmin talvella tai keväällä. Viikonloppuna sairaalaan tulleista potilaista kuoli ensimmäisen vuorokauden aikana enemmän kuin arkipäivinä tulleista.
Keskimääräinen hoitoaika oli pisin ja sairaalahoito runsainta sairauden loppuvaiheessa kuoleman lähestyessä. Ensimmäisen KAT:n aiheuttaman hoitojakson jälkeen noin neljännes potilaista oli kuollut vuoden sisällä ja viiden vuoden kuluessa noin puolet.
Keuhkoahtaumataudin sairaalahoito on tehostunut Suomessa 1990-luvulla sairaansijojen vähentyessä. Hoitoajat ovat lyhentyneet ja pahenemisvaiheiden sairaalakuolleisuus on vähäistä. Väestön ikääntyminen on kuitenkin ennakoitava ja sairaalaa korvaavia hoitomuotoja kehitettävä taudista aiheutuneiden kustannusten hillitsemiseksi. Varhaisdiagnostiikkaa ja avokuntoutusta on kehitettävä ja erityinen huomio kiinnitettävä sairauden loppuvaiheen asianmukaiseen hoitoon.
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Epidémiologie en soins primaires de la thrombose veineuse superficielle des membres inférieurs / Epidemiology of superficial-vein thrombosis of the legs in primary careFrappé, Paul 14 October 2015 (has links)
La sévérité potentielle de la thrombose veineuse superficielle (TVS) des membres inférieurs a récemment été documentée par des études réalisées en soins secondaires et tertiaires. Son épidémiologie reste cependant inconnue en soins primaires. Le premier objectif de ce travail était de mesurer la prévalence de la TVS en soins primaires, ainsi que le taux d'évènements thromboemboliques concomitants au moment du diagnostic. Pour y répondre, un réseau de recherche collaborative entre médecins généralistes et médecins vasculaires de la région stéphanoise a été mis en place. Une étude transversale descriptive a été réalisée au sein de ce réseau pendant un an. La prévalence annuelle de la TVS a été mesurée à 0,64 pour mille habitants. Au moment du diagnostic, 24,6% des TVS étaient associées à une thrombose veineuse profonde symptomatique et 4,7% à une embolie pulmonaire symptomatique. Une seconde étude a recherché une variation saisonnière de la fréquence de la TVS en analysant les données individuelles de trois études aux designs différents ; l'étude STENOX, l'étude POST et l'étude STEPH. Une variation significative n'a été retrouvée que dans l'étude POST, et les peak-to-low ratios étaient inférieurs à 1,2 dans les trois études. Ainsi, si une variation existe, celle-ci parait être de faible envergure, sans conséquence sur la pratique et la recherche / The potential severity of superficial vein thrombosis (SVT) of the lower limbs has recently been shown by studies perfomed in secondary and tertiary care. The epidemiology of SVT remains unknown in primary care. The first objective of this study was to measure the prevalence of SVT in primary care, and the rate of concomitant thromboembolic events at diagnosis. A collaborative research network between general practitioners and vascular physicians from Saint-Etienne has been set up. A cross-sectional study has been conducted within this network during one year. The annual prevalence of SVT was measured to 0.64 per thousand inhabitants. At diagnosis, 24.6% of SVT were associated with symptomatic deep vein thrombosis and 4.7% with symptomatic pulmonary embolism. A second study was looking for a seasonal variation of SVT frequency by analyzing individual data from three studies with different designs; the STENOX study, the POST study and the STEPH study. A significant variation was found only in the POST study, and peak-to-low ratios were below 1.2 in the three studies. Thus, if other more powerful and exhaustive studies could find a seasonal variation, that variation would probably be of low magnitude and without clinical significance
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THE INFLUENCE OF SEASON, FLOW REGIME, AND WATERSHED LAND USE AND LAND COVER ON NUTRIENT DELIVERY TO TWO RAPIDLY URBANIZING WATERSHEDS IN CENTRAL INDIANA, USACasey, Leda René 20 March 2007 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / This study explores relationships between temperate stream geochemistry and watershed land cover in two temperate streams, Fishback Creek and School Branch Creek, located in a rapidly urbanizing area on the northwest side of Indianapolis in Eagle Creek Watershed, Indiana. The temporal and spatial patterns of NO3-N, PO4, DOC, SiO2, Cl-, and Na+ were assessed to understand the influence of land cover on the magnitude and timing of water, chemical, and nutrient delivery to streams. Results of the study indicate that the influences of different land cover types on water delivery to streams and in-stream water quality vary seasonally and with respect to flow regime, that urbanization may result in decreased nitrate input, and that phosphate and dissolved organic carbon concentrations will likely remain constant as the watershed is developed. Results also indicate that riparian buffer downstream of intense agriculture lands dilutes high agricultural NO3-N concentrations, but not enough to return in-stream concentrations to natural levels.
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Effet de la végétation sur la performance des biorétentions en climat froidBeral, Henry 05 1900 (has links)
Les systèmes de biorétention sont de plus en plus utilisés pour gérer le ruissellement des eaux pluviales urbaines. Bien que les plantes soient une composante essentielle des biorétentions, il existe à ce jour peu de preuves de la contribution des espèces choisies, en particulier dans les climats tempérés à grande variation saisonnière. Aussi, les bactéries et les champignons peuvent jouer un rôle majeur dans la performance des biorétentions en améliorant la qualité de l'eau ou en soutenant l'efficacité des plantes. Mais à ce jour, on sait peu de choses sur les microorganismes peuplant les biorétentions et encore moins sur l'influence des choix de conception de ce système et ses conséquences sur la contribution de ces organismes. D’autre part, en climat froid, l'utilisation de sels de déglaçage génère des ruissellements salins qui pourraient affecter les performances des biorétentions, notamment en impactant les processus biologiques en cours dans le système.
Le but de mon étude était de comparer la contribution de la végétation à la performance des biorétentions en fonction de l'espèce plantée, de tester l'impact du ruissellement salin sur l'hydrologie et la filtration des contaminants par le système en fonction des espèces végétales utilisées, et de caractériser l'influence de ces 2 facteurs sur la diversité, la composition et l'abondance relative des bactéries et champignons au sein des biorétentions.
J’ai réalisé une expérience en mésocosmes avec 4 espèces végétales couramment utilisées en biorétention et couvrant un large éventail de types biologiques (Cornus sericea, Juncus effusus, Iris versicolor, Sesleria autumnalis). Pour simuler un ruissellement printanier chargé en sel de déglaçage, l'eau de ruissellement semi-synthétique utilisée pour l'irrigation à était complétée au printemps avec quatre concentrations de NaCl (0, 250, 1000 ou 4000 mg Cl/L). Le séquençage des gènes 16S et ITS ont été utilisé comme indicateur de diversité, de composition et d'abondance relative bactérienne et fongique.
En général, tous les mésocosmes de biorétention ont significativement réduit les volumes d'eau, les débits de pointe et les charges de contaminants. Certaines plantes améliorent significativement les performances en augmentant la perte d'eau par évapotranspiration pendant la période de croissance (jusqu'à 2,5 fois) et en réduisant le débit d'eau (jusqu'à 2,7 fois). Les plantes ont amélioré l’enlèvement des macronutriments, avec un enlèvement massique moyen de 55 % pour l’Azote total, 81 % pour le Phosphore total et 61 % pour le K, contre -6 % (relargage), 61 % et 22 % respectivement pour les non plantés. À l'exception des Sesleria, l’enlèvement des éléments traces par les mésocosmes plantés était généralement plus élevée que chez les non plantés (jusqu'à 8,7 %). Leur niveau de contribution suivait le même ordre que leur taux d'évapotranspiration et leur taille globale (Cornus > Juncus > Iris > Sesleria). Même à la concentration la plus élevée de NaCl testée, aucun effet sur la réduction du volume d'eau et les débits n'a été détecté. En revanche, le ruissellement chargé en sel a temporairement augmenté l’enlèvement de certains métaux tels que Cr, Ni, Pb et Zn. Dans l’ensemble, les plantes ont très bien toléré le passage du ruissellement chargé de sel au printemps. Tous les mésocosmes ont naturellement été colonisés par des bactéries et des champignons adaptés à un environnement humide et contaminé. Parmi les taxons dominants, plusieurs ont des fonctions en lien avec la performance des biorétentions, telles que l'implication dans le cycle de l'azote, la dégradation des hydrocarbures, la tolérance et la remédiation de métaux, ou des symbiotes végétaux.
Ma thèse souligne l'importance du choix des espèces végétales sur la performance des biorétentions. D’une part en raison de leur contribution différentielle à la réduction du volume d'eau, des débits de pointe et l'enlèvement des contaminants, en particulier des macronutriments, et d’autre part à cause de leur influence sur la composition et l’abondance des microorganismes. Même si plusieurs des bactéries et champignons dominants ce système auraient la capacité de contribuer à la performance des biorétentions, d’autres études devront être menées pour vérifier leur activité. Finalement, ma thèse a démontré que la présence de sel de déverglaçage dans le ruissellement ne devrait pas être un frein à la mise en place de cellules de biorétention, puisque qu'aux concentrations habituellement observées à la suite d’épandages, aucun effet négatif sur la performance, la végétation ou les communautés bactérienne et fongique n’a été observé dans la présente thèse. Cependant, la libération des cations structurants du sol et l’exfiltration du sels devrait être faire l’objet d’un suivi à plus long terme.
Bien que ces expériences aient permis d'analyser l'effet des espèces végétales et des sels de déverglaçage sur la réduction du volume d'eau, des débits de pointe, l’enlèvement des contaminants, et les micro-organismes, l'extrapolation de ces résultats à grande échelle doit être effectuée avec prudence. En effet, les mésocosmes sont des systèmes artificiels qui ne reproduisent pas entièrement les conditions réelles des biorétentions à grande échelle, notamment en ce qui concerne les températures hivernales inférieures à zéro, et ne sont étudiés qu’un lapse de temps. Aussi, les biorétentions réelles sont rarement plantées en monoculture, de sorte que les interactions entre les espèces végétales et les microorganismes pourraient influencer la performance du système. Pour une application réussie des conclusions de cette étude à l'échelle pratique, il serait essentiel que des projets pilotes valident ces résultats. / Bioretention systems are increasingly used to manage urban stormwater runoff. Plants are an essential component of bioretention, improving water quality and reducing runoff volume and peak flows. Although plants are an essential component of bioretentions, there is little evidence on how their contribution changes according to the species chosen, especially in temperate climates with large seasonal variations. In addition, bacteria and fungi could play a major role in bioretention performance by improving water quality or supporting plant efficiency. But to date, little is known about the microorganisms living in bioretentions and even less about the influence of the design choices of this system and therefore its consequences on the contribution of these organisms. In cold climates, the use of de-icing salts generates saline runoff which could affect the bioretentions performance, especially by reducing biological processes.
The aim of my study was to compare the contribution of vegetation to the performance of bioretentions according to the species planted, to test the impact of saline runoff on the hydrology and the filtration of contaminants by the system according to the plant species used, and to characterize the influence of these 2 factors on the diversity, composition and relative abundance of bacteria and fungi within bioretentions.
I performed a mesocosm experiment with 4 plant species commonly used in bioretention and covering a wide range of biological types (Cornus sericea, Juncus effusus, Iris versicolor, Sesleria autumnalis). To simulate spring salt-laden runoffs, the semi-synthetic runoff water used for irrigation was supplemented in spring with four concentrations of NaCl (0, 250, 1000 or 4000 mg Cl/L). Sequencing of 16S and ITS genes was used as bacterial and fungal diversity, composition and relative abondance indicator.
In general, all bioretention mesocosms significantly reduced water volumes, peak flows, and contaminant loads. Some plants significantly increased the performances, by increasing water loss through evapotranspiration during the growing period (up to 2.5 times) and reducing water flow (up to 2.7 times). Plants improved macronutrients removal, with an average mass removal of 55% for total nitrogen, 81% for total phosphorus and 61% for K compared to –6% (release), 61% and 22% respectively for the unplanted. Except for Sesleria, mass removal of trace elements in planted mesocosms was generally higher than in unplanted ones (up to 8.7%). Their contribution level followed the same order as their evapotranspiration rate and overall size (Cornus > Juncus > Iris > Sesleria). Even at the highest concentration of NaCl tested, no impact on water volume reduction and flow rates were detected. In contrast, salt-laden runoffs temporarily increased removal of some metals such as Cr, Ni, Pb, and Zn. Overall, the plants tolerated the passage of salt runoff in spring. All bioretention mesocosms were naturally colonized by bacteria and fungi adapted to a humid and contaminated environment. Among the dominant taxa, several described functions related to the bioretention performances, such as involvement in the nitrogen cycle, the degradation of hydrocarbons, the tolerance and remediation of metals, or plant symbionts.
My thesis emphasizes the importance of the plant species choice on the bioretentions performance. firstly because of their differential contribution to the water volume reduction, peak flows, and the contaminants removal, in particular macronutrients, secondly through their influence on the composition and abundance of microorganisms. Even though several of the dominant bacteria and fungi found would have the ability to contribute to the performance of bioretentions, further studies will be needed to verify their activity. Finally, my thesis demonstrated that the presence of de-icing salt in the runoff should not be a hindrance to the bioretention cells implementation, since at concentrations usually observed following salt spreading, no negative effect on the bioretentions performance, on the vegetation or the bacterial and fungal communities were observed in this thesis. However, the release of soil-structuring cations as well as salts exfiltration should be monitored in the longer term.
Although these experiments allowed for the analysis of the effect of plant species and de-icing salts on the reduction of water volume, peak flow rates, contaminant removal, and microorganisms, the extrapolation of these results to a larger scale must be done with caution. Despite the advantage of characterizing the performance of bioretention in mesocosms in terms of replication and factor control, it is important to recognize that this approach also has its limitations. Mesocosms are artificial systems that do not fully replicate the real-world conditions of large-scale bioretention, especially concerning sub-zero winter temperatures and the limited time frame of study. The size of the mesocosms could lead to edge effects, such as preferential flows, while real-world scenarios involve slopes that create heterogeneous conditions within these basins, influencing factors like frequency and quantity of water received. Additionally, real bioretention systems are seldom planted as monocultures, thus interactions between plant species and microorganisms may impact system performance. For successful implementation of the findings of this study on a practical scale, validation through pilot projects would be essential.
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Contribuição à farmacognosia de Artemisia annua L. e Bidens pilosa L. (Asteraceae). Acompanhamento da variação de metabólitos secundários em diferentes fases fenológicas, órgãos e extratos vegetais, aspectos botânicos e avaliação da atividade antileishmania in vitro / Pharmacognosy of Artemisia annua L and Bidens pilosa L. (Asteraceae). Growth stages variation of secondary metabolites in extracts from plant parts collected in different growth stages, botanical aspects and in vitro evaluation of the antileishmanial activitySilva, Fabiana Lima 29 September 2008 (has links)
Na busca por espécies vegetais com atividade antileishmania, selecionaram-se, para o estudo, duas espécies bem conhecidas da família Asteraceae: Artemisia annua L. e Bidens pilosa L. Ambas são reconhecidamente utilizadas na medicina popular, como antiprotozoárias. Apesar de terem sido amplamente estudadas em diversos aspectos, alguns permaneceram inexplorados, até o momento, e foram abordados, neste trabalho. As duas espécies foram analisadas quanto aos aspectos químico e biológico de extratos (hidroetanólico e infuso) e frações orgânicas selecionados, em função da atividade antileishmania in vitro, frente às formas promastigotas de Leishmania amazonensis. Os extratos foram obtidos a partir de órgãos vegetais, em estados de conservação diferentes (in natura, droga) e coletados em fenofases distintas. Extratos e frações orgânicas das espécies estudadas mostraram promissora atividade antileishmania in vitro e baixo nível de citotoxicidade in vitro em células epiteliais humanas (HEP-2). No estudo químico dos extratos e frações bioativos, realizaram-se análises qualitativas e/ou quantitativas de terpenos, flavonóides e de marcadores específicos (artemisinina, quercetina e rutina), avaliando-se a variação da composição dos mesmos, nas diferentes fenofases consideradas. Discutiram-se as possíveis relações existentes entre a composição química e a atividade biológica verificada. Aspectos inéditos do estudo morfoanatômico de partes aéreas de A. annua foram descritos. / Plants are potential sources of new antileishmanial drugs. Two well-known antiprotozoal species were selected, from the Asteraceae family, for this study: Artemisia annua L and Bidens pilosa L. Despite the traditional and scientific accumulated knowledge, some aspects were not investigated before and were the subject of this work. Several extracts (infusions and ethanol 96 °GL) and selected fractions from both species were evaluated according to the different parameters, such as: plant organs and/or parts, growth stages and drying state of starting materials (fresh, drug). Fractions were selected among those more active against promastigotes of Leishmania amazonensis. Ethanol extracts and their fractions showed a high level of in vitro antileishmanial activity and a low cytotoxicity on epithelial human cells (HEP-2). Qualitative and/or quantitative analysis of extracts and fractions were performed for terpenes, flavonoids and selected markers (artemisinin, quercetin and rutin) in order to characterize them and evaluate variations during the different growth stages. Correlations of the chemical composition and the biological activity were discussed. The main anatomical characters of the aerial parts of A. annua were described for the first time and illustrated by photomicrographs.
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