131 |
Unusual Acylation Properties Of Type II Fatty Acid Biosynthesis Acyl Carrier ProteinsMisra, Ashish 07 1900 (has links)
This thesis entitled ‘ Unusual Acylation Properties of Type II Fatty Acid Biosynthesis Acyl Carrier Proteins’ describes the discovery of self-acylation and malonyl transferase activity in acyl carrier proteins involved in type II fatty acid biosynthesis and assigns a physiological role to these processes inside the cellular milieu. Acyl carrier protein (ACP) is one of the most abundant proteins present inside the cell and almost 4% enzymes require it as a cofactor. Acyl carrier proteins can exist either as discrete proteins or as domains of large functional proteins. They function in a variety of synthases as central molecules to which growing acyl intermediates and nascent product molecules are covalently tethered during the elongation and modification steps required to produce the final product. A prototypical bacterial ACP is composed of 70-80 amino acids and is generally expressed in the apo form. It is post-translationally modified to active holo form by the addition of 4'-phosphopantetheine moiety to an absolutely conserved serine residue in a reaction catalyzed by holo-ACP synthase or 4'-phosphopantetheine transferase.
Chapter 1 surveys literature related to carrier proteins inside the cell and describes the thesis objective. It also presents an overview of the acyl carrier proteins and their involvement in various metabolic pathways inside the cell. The chapter details the structural organization of acyl carrier proteins from various sources revealing the conservation in their structure and also details the molecular basis of interaction of ACP with other enzymes inside the cell.
The discovery of unusual self-acylation property in acyl carrier proteins involved in polyketide biosynthesis and its absence in acyl carrier proteins involved in fatty acid biosynthesis prompted me to investigate the reasons for this selective behavior. Discovery of self-acylation property in acyl carrier proteins Plasmodium falciparum and chloroplast targeted Brassica napus acyl carrier proteins involved in type II fatty acid biosynthesis and the mechanism of this reaction forms the basis of
Chapter 2. In this chapter it has been shown that self-acylation property is intrinsic to a given acyl carrier protein and is not dependent on the pathway in which it is involved. Based on primary sequence analysis and site directed mutagenesis studies presence of an aspartate/glutamate has been identified to be critical for the self-acylation event. Furthermore, it has also been shown that the self-acylation event in type II fatty acid biosynthesis acyl carrier proteins is highly specific in nature employing only dicarboxylic acid –CoAs as substrates unlike the polyketide biosynthesis acyl carrier proteins which utilize both dicarboxylic acid and β-keto acid thiol ester -CoAs as substrates. The detailed kinetics of these reactions has also been worked out. Combining all the results a plausible mechanism for the self-acylation reaction has been proposed.
Chapter 3 describes the discovery of a novel malonyl transferase behavior in acyl carrier proteins involved in type II fatty acid biosynthesis. Malonyl transferase property in ACPs of type II FAS from a bacterium (Escherichia coli), a plant (Brassica napus) and a parasitic protozoon (Plasmodium falciparum) were investigated to present a unifying paradigm for the mechanism of malonyl transferase behavior in ACPs. Identification of malonyl transferase property in Plasmodium falciparum ACP and Escherichia coli ACP (EcACP) and the absence of this property in Brassica napus ACP has been described in this chapter. Detailed investigations demonstrated that presence of an arginine or a lysine in loop II and an arginine or glutamine at the start of helix III as the residues that are critical for the transferase activity. In order to assign a physiologic function to these unusual acylation properties, fabD(Ts) mutant strain of Escherichia coli was utilized for heterologous complementation by the various wild type and mutant ACPs that are able to catalyze either or both of the activities. Growth of the mutant strain at non-permissive temperature, when complemented with ACPs catalyzing both the reactions confirmed that these properties have a physiologic relevance. Extensive mutagenesis experiments in conjunction with complementation studies allowed me to propose a plausible mechanism on how the self-malonylation and malonyl transferase properties operate in tandem.
Chapter 4 describes the thermodynamic characterization of self-acylation process using Isothermal Titration Calorimetry. Isothermal Titration Calorimetric studies on the binding of malonyl, succinyl, butyryl and methylmalonyl –CoA to Plasmodium falciparum and Brassica napus acyl carrier proteins were performed to investigate the role of thermodynamic parameters in the specificity of self-acylation reaction. Calculation of the parameters showed that the thermodynamics does not control the self-acylation reaction.
The evolution of self-acylation property in various acyl carrier proteins and its possible significance in the evolution of various metabolic events is described in Chapter 5. Extensive bioinformatics search was performed and phylogenetic analysis on acyl carrier proteins from 60 different taxa was done using the MEGA4 program. Analysis showed that this property was first found in cyanobacterium. Later, during the course of evolution this property was lost in most acyl carrier proteins, and was retained either in acyl carrier proteins that are targeted to organelles of cyanobaterial orgin viz. apicoplast in apicomplexans and chlorplasts in plants or in acyl carrier proteins involved in secondary metabolic events such as polyketide biosynthesis.
Chapter 6 summarizes the findings of the thesis. Acyl carrier protein from Plasmodium falciparum, Brassica napus and Escherichia coli were characterized for their self-acylation and malonyl transferase properties and a combined mechanism for these two properties is proposed. The work done also provides an in vivo rationale to these in vitro processes. Furthermore, the evolutionary significance of the self-acylation behavior is also discussed in the thesis. The thesis also probes into the thermodynamics of the self-acylation reaction in Plasmodium falciparum and Brassica napus acyl carrier proteins. Thus, the thesis adds a new dimension to the much unexplored ACP biology and paves the way to study in vivo roles of these processes in detail.
Appendix I describes the Isothermal Titration calorimetric characterization of binding of various acyl-PO4 molecules to Escherichia coli PlsX (Acyl-phosphate acyltransferase). PlsX, the first enzyme of phosphatidic acid biosynthesis pathway catalyzes the conversion of acyl-ACP into acyl-PO4, which is further used by other enzymes leading to the formation of phosphatidic acid. ITC results presented in this section show that longer chain length acyl-PO4 molecules show better binding to PlsX, as compared to the smaller ones demonstrating that long chain acyl molecules serve as better substrates for phosphatidic acid synthesis.
|
132 |
Etude biotique et abiotique de l'habitat préférentiel de l'écrevisse à pattes blanches (Austropotamobius pallipes) dans l'ouest de la France. Implications pour sa gestion et sa conservationTrouilhé, M.-C. 16 June 2006 (has links) (PDF)
De novembre 2002 à décembre 2005, l'habitat préférentiel de l'écrevisse indigène à pattes blanches (Austropotamobius pallipes) a été défini dans le « pays de Gâtine » (Deux-Sèvres, France). Pour cette étude, huit cours d'eau, répartis dans quatre bassins hydrographiques différents, ont été sélectionnés. Sur chaque ruisseau, deux points de prélèvement ont été choisis : le premier, le plus en amont, était situé au niveau de la population d'A. pallipes et le second, 2 à 3 km en aval, était dépourvu d'écrevisse à pattes blanches. Vingt-trois paramètres physico-chimiques, concernant les composantes minérale et organique de l'eau, ont été très régulièrement mesurés et quatre prélèvements de la faune de macroinvertébrés benthiques ont été réalisés. Ce suivi a permis d'acquérir une importante base de données pour caractériser les tolérances d'A. pallipes vis-à-vis de certains paramètres ce qui nous a conduit à discuter son statut de bioindicateur de la qualité des eaux. L'utilisation d'analyses multivariées (Analyse en Composantes Principales majoritairement) a montré (i) que la matière organique serait un des facteurs discriminants dans la présence/absence d'A. pallipes et (ii) que, précisément, la présence d'A. pallipes est associée à celle de familles de macroinvertébrés les plus sensibles aux pollutions organiques. L'ACP a aussi permis de réduire considérablement le nombre de paramètres abiotiques et biotiques informatifs. De plus, l'utilisation de ces paramètres sélectionnés pour modéliser par Réseaux de Neurones Artificiels (RNA) la présence/absence d'A. pallipes a fourni des résultats satisfaisants et prometteurs en terme de gestion et de conservation de cette espèce menacée.
|
133 |
L'accord de Cotonou et les contradictions du droit international : l'intégration des règles de l'Organisation mondiale du commerce et des droits humains dans la coopération ACP-CEGallie, Martin January 2006 (has links)
Ce travail poursuit deux objectifs principaux: un objectif juridique et un objectif d'ordre
épistémologique.
Il s'agit tout d'abord de rendre compte d'un point de vue juridique et empirique les
implications du passage des Conventions de Lomé à l'Accord de Cotonou. Nous examinons
les implications de la redéfinition des accords de coopération sur les politiques de
développement des Etats ACP, et plus précisément l'évolution des obligations à la charge des
deux groupes de pays dans les domaines du commerce international et des droits humains.
Dans un premier temps, nous montrons que la non réciprocité des obligations commerciales
entre les deux groupes de pays qui caractérisait les Conventions de Lomé est définitivement
écartée au profit d'obligations réciproques et identiques pour les deux groupes de pays en
conformité des dispositions de l'Organisation mondiale du commerce. Le principe de
l'inégalité compensatrice est abandonné au profit de la libéralisation commerciale. Le
traitement spécial et différencié, pourtant consacré dans l'Accord instituant l'OMC, apparaît
ainsi dépourvu d'une grande partie de son intérêt.
Dans un deuxième temps, ce sont les obligations relatives au respect des droits humains qui
retiennent notre attention. L'élargissement du champ de la coopération à des questions
considérées depuis l'indépendance comme des questions relevant de la compétence interne
des Etats, se traduit par une remise en cause de la souveraineté des Etats ACP. Le principe de
non-ingérence dans les affaires intérieures, héritage de la décolonisation, est ainsi remis en
question. Mais surtout, nous établissons que tous les droits humains ne sont pas concernés par
cet élargissement.
Le deuxième objectif de ce travail est d'ordre épistémologique. Il VIse à démontrer le
caractère heuristique d'une analyse constructiviste du droit pour la compréhension de notre
objet mais aussi l'intérêt de ce type d'approche au regard des débats qui structurent le champ
disciplinaire sur les rapports entre les droits humains et le droit du commerce international. A
travers l'étude de l'Accord de Cotonou, nous tentons de mettre en lumière le fait que les droits
humains et règles de l'OMC n'évoluent ni de manière complémentaire ni séparément et qu'il
ne suffit pas de raisonner en termes de «rattrapage» et de correctifs ponctuels afin
d'harmoniser ces deux champs de règles.
En conclusion nous constatons que cinq ans ont suffi aux institutions européennes pour
réaliser un véritable «exploit» politique. Elles ont réussi à renverser l'ensemble des
obligations économiques qui étaient à la charge des deux groupes de pays, à supprimer les
protocoles produits en faveur des ACP, à faire adopter un programme de libéralisation
commercial qui va au-delà de tout ce qui a été négocié jusqu'ici au niveau multilatéral et ce,
sous couvert de mise en conformité avec les dispositions de l'ÜMC. Enfin, l'DE a fragilisé le
Groupe ACP en le morcelant en six régions, dont certaines n'ont aucune existence
institutionnelle, avec lesquelles elle négocie actuellement un vaste programme de
libéralisation commerciale.
En ce qui a trait au respect des droits humains on constate qu'à la différence des normes de
l'OMC qui font l'objet de négociations permanentes et structurent le cadre institutionnel et le
fond de la coopération, le respect des droits humains ne fait pas ou peu l'objet de négociations
entre les deux groupes de pays. De plus, s'ils occupent désormais une place centrale dans le
discours des institutions communautaires en charge du développement, le seul mécanisme mis
en oeuvre pour sanctionner leurs violations est utilisé d'une manière partiale et sélective. Seule
l'DE peut l'utiliser et elle ne choisit de le faire que quand la sanction infligée à un pays ACP
ne met pas en péril ses propres intérêts. Bref, l'intégration des droits humains dans le cadre de
la coopération contribue davantage aujourd'hui à une remise en cause de l'égalité souveraine
des Etats qu'à la promotion des Pactes de 1966, au respect des normes de l'OIT ou du droit
des réfugiés. / This work pursues two aims. The first one is to seek to understand and to explain the stakes
and the implications of the transformation of the Lomé convention into the Cotonou
agreement, from a constructive approach of law. It is then a question of contributing to the
legal thought concerning the degree of complimentary and coherence between the two fields
of the internationallaw, human rights and international trade law.
The second aim led us to look into the question of the real integration, which proved to be
selective, of the standards coming from these two fields of law into the Cotonou Agreement.
In the cooperation, the breach of human rights, as the OMC standards, is appreciated in a
subjective and unilateral way by the E.U.
Far from contributing to a complementary approach, the cooperation reinforces the dichotomy
between these two fields of internationallaw, by treating them on a hierarchical basis. / "Thèse présentée à la Faculté des études supérieures de l'Université de Montréal en vue de l'obtention du grade de Docteur en Droit (LL.D.) Et à A la faculté de droit Jean Monnet en vue de l'obtention du doctorat en Sciences Juridiques"
|
134 |
A new era for the EU-SADC trade relationship: a critical analysis of the EU-SADC EPA and the Impact on regional integration in SADC and South Africa's role in the negotiations.Keller, Sara Regina. January 2007 (has links)
<p>The EPA&rsquo / s will have an impact on regional integration in Africa, especially in the SADC region. The region has been split between the SADC and ESA EPA configuration therefore impacting on regional integration objectives set out under the SADC Trade Protocol.The EPA&rsquo / s will be concluded separately with six of the sub groupings under the ACP grouping. With the EU-SADC EPA negotiations has come a problem of overlapping of membership of the different regions which has created confusion and conflicts. Members of Southern African Development Cooperation (SADC) did not all enter into the EU-SADC EPA has one. The EU-SADC EPA configuration consists of Angola, Botswana, Lesotho, Mozambique, Namibia, South Africa, Swaziland and Tanzania. The rest of the SADC member states are negotiating with the EU-ESA configuration. With South Africa having been allowed into the negotiations, its role should be examined and what it can contribute to the negotiations. Another conflict that has been created is the fact that South Africa has its own bilateral agreement with the EU thus putting stain on the trade relationship between South African and the rest of the SADC countries.</p>
|
135 |
Segmentation d'images par combinaison adaptative couleur-texture et classification de pixels. : Applications à la caractérisation de l'environnement de réception de signaux GNSSATTIA, Dhouha 03 October 2013 (has links) (PDF)
En segmentation d'images, les informations de couleur et de texture sont très utilisées. Le premier apport de cette thèse se situe au niveau de l'utilisation conjointe de ces deux sources d'informations. Nous proposons alors une méthode de combinaison couleur/texture, adaptative et non paramétrique, qui consiste à combiner un (ou plus) gradient couleur et un (ou plus) gradient texture pour ensuite générer un gradient structurel utilisé comme image de potentiel dans l'algorithme de croissance de régions par LPE. L'originalité de notre méthode réside dans l'étude de la dispersion d'un nuage de point 3D dans l'espace, en utilisant une étude comparative des valeurs propres obtenues par une analyse des composantes principales de la matrice de covariance de ce nuage de points. L'approche de combinaison couleur/texture proposée est d'abord testée sur deux bases d'images, à savoir la base générique d'images couleur de BERKELEY et la base d'images de texture VISTEX. Cette thèse s'inscrivant dans le cadre des projets ViLoc (RFC) et CAPLOC (PREDIT), le deuxième apport de celle-ci se situe au niveau de la caractérisation de l'environnement de réception des signaux GNSS pour améliorer le calcul de la position d'un mobile en milieu urbain. Dans ce cadre, nous proposons d'exclure certains satellites (NLOS dont les signaux sont reçus par réflexion voir totalement bloqués par les obstacles environnants) dans le calcul de la position d'un mobile. Deux approches de caractérisation, basées sur le traitement d'images, sont alors proposées. La première approche consiste à appliquer la méthode de combinaison couleur/texture proposée sur deux bases d'images réelles acquises en mobilité, à l'aide d'une caméra fisheye installée sur le toit du véhicule de laboratoire, suivie d'une classification binaire permettant d'obtenir les deux classes d'intérêt " ciel " (signaux LOS) et " non ciel " (signaux NLOS). Afin de satisfaire la contrainte temps réel exigée par le projet CAPLOC, nous avons proposé une deuxième approche basée sur une simplification de l'image couplée à une classification pixellaire adaptée. Le principe d'exclusion des satellites NLOS permet d'améliorer la précision de la position estimée, mais uniquement lorsque les satellites LOS (dont les signaux sont reçus de manière direct) sont géométriquement bien distribués dans l'espace. Dans le but de prendre en compte cette connaissance relative à la distribution des satellites, et par conséquent, améliorer la précision de localisation, nous avons proposé une nouvelle stratégie pour l'estimation de position, basée sur l'exclusion des satellites NLOS (identifiés par le traitement d'images), conditionnée par l'information DOP, contenue dans les trames GPS.
|
136 |
Regression analysis of caterpillar 793D haul truck engine failure data and through-life diagnostic information using the proportional hazards modelCarstens, Wiehahn Alwyn 03 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Physical Asset Management (PAM) is becoming a greater concern for companies
in industry today. The widely accepted British Standards Institutes’ specification
for optimized management of physical assets and infrastructure is PAS55.
According to PAS55, PAM is the “systematic and co-ordinated activities and practices
through which an organization optimally manages its physical assets, and
their associated performance, risks and expenditures over their life cycle for the
purpose of achieving its organizational strategic plan”.
One key performance area of PAM is Asset Care Plans (ACP). These plans
are maintenance strategies which improve or ensure acceptable asset reliability
and performance during its useful life. Maintenance strategies such as Condition
Based Maintenance (CBM) acts upon Condition Monitoring (CM) data, disregarding
the previous failure histories of an asset. Other maintenance strategies,
such as Usage Based Maintenance (UBM), is based on previous failure histories,
and does not consider CM data.
Regression models make use of both CM data and previous failure histories
to develop a model which represents the underlying failure behaviour of the asset
under study. These models can be of high value in ACP development due to the
fact that Residual Useful Life (RUL) can be estimated and/or the long term life cycle cost can be optimized.
The objective of this thesis was to model historical failure data and CM data
well enough so that RUL or optimized preventive maintenance instant estimations
can be made. These estimates were used in decision models to develop maintenance
schedules, i.e. ACPs.
Several regression models were evaluated to determine the most suitable model
to achieve the objectives of this thesis. The model found to be most suitable for
this research project was the Proportional Hazards Model (PHM). A comprehensive
investigation on the PHM was undertaken focussing on the mathematics and
the practical implementation thereof.
Data obtained from the South African mining industry was modelled with the
Weibull PHM. It was found that the developed model produced estimates which
were accurate representations of reality. These findings provide an exciting basis
for the development of futureWeibull PHMs that could result in huge maintenance
cost savings and reduced failure occurrences. / AFRIKAANSE OPSOMMING: Fisiese Bate Bestuur (FBB) is besig om ’n groter bekommernis vir maatskappye
in die bedryf te word. Die Britse Standaarde Instituut se spesifikasie vir optimale
bestuur van fisiese bates en infrastruktuur is PAS55. Volgens PAS55 is FBB die
“sistematiese en gekoördineerde aktiwiteite en praktyke wat deur ’n organisasie
optimaal sy fisiese bates, hul verwante prestasie, risiko’s en uitgawes vir die doel
van die bereiking van sy organisatoriese strategiese plan beheer oor hul volle lewensiklus
te bestuur”.
Een Sleutel Fokus Area (SFA) van FBB is Bate Versorgings Plan (BVP) ontwikkeling.
Hierdie is onderhouds strategieë wat bate betroubaarheid verbeter of
verseker tydens die volle bruikbare lewe van die bate. Een onderhoud strategie
is Toestands Gebasseeerde Onderhoud (TGO) wat besluite baseer op Toestand
Monitering (TM) informasie maar neem nie die vorige falingsgeskiedenis van die
bate in ag nie. Ander onderhoud strategieë soos Gebruik Gebasseerde Onderhoud
(GGO) is gebaseer op historiese falingsdata maar neem nie TM inligting in ag nie.
Regressiemodelle neem beide TM data en historiese falings geskiedenis data in
ag ten einde die onderliggende falings gedrag van die gegewe bate te verteenwoordig. Hierdie modelle kan baie nuttig wees vir BVP ontwikkeling te danke aan die
feit dat Bruikbare Oorblywende Lewe (BOL) geskat kan word en/of die langtermyn
lewenssilus koste geoptimeer kan word.
Die doelwit van hierdie tesis was om historiese falingsdata en TT data goed
genoeg te modelleer sodat BOL of optimale langtermyn lewensiklus kostes bepaal
kan word om opgeneem te word in BVP ontwikkeling. Hierdie bepalings word dan
gebruik in besluitnemings modelle wat gebruik kan word om onderhoud skedules
op te stel, d.w.s. om ’n BVP te ontwikkel.
Verskeie regressiemodelle was geëvalueer om die regte model te vind waarmee
die doel van hierdie tesis te bereik kan word. Die mees geskikte model vir die navorsingsprojek
was die Proporsionele Gevaarkoers Model (PGM). ’n Omvattende
ondersoek oor die PGM is onderneem wat fokus op die wiskunde en die praktiese
implementering daarvan.
Data is van die Suid-Afrikaanse mynbedryf verkry en is gemodelleer met behulp
van die Weibull PGM. Dit was bevind dat die ontwikkelde model resultate
geproduseer het wat ’n akkurate verteenwoordinging van realiteit is. Hierdie bevindinge
bied ’n opwindende basis vir die ontwikkeling van toekomstige Weibull
Proporsionele Gevaarkoers Modelle wat kan lei tot groot onderhoudskoste besparings
en minder onverwagte falings.
|
137 |
Statistical properties of barycenters in the Wasserstein space and fast algorithms for optimal transport of measures / Propriétés statistiques du barycentre dans l’espace de WassersteinCazelles, Elsa 21 September 2018 (has links)
Cette thèse se concentre sur l'analyse de données présentées sous forme de mesures de probabilité sur R^d. L'objectif est alors de fournir une meilleure compréhension des outils statistiques usuels sur cet espace muni de la distance de Wasserstein. Une première notion naturelle est l'analyse statistique d'ordre un, consistant en l'étude de la moyenne de Fréchet (ou barycentre). En particulier, nous nous concentrons sur le cas de données (ou observations) discrètes échantillonnées à partir de mesures de probabilité absolument continues (a.c.) par rapport à la mesure de Lebesgue. Nous introduisons ainsi un estimateur du barycentre de mesures aléatoires, pénalisé par une fonction convexe, permettant ainsi d'imposer son a.c. Un autre estimateur est régularisé par l'ajout d'entropie lors du calcul de la distance de Wasserstein. Nous nous intéressons notamment au contrôle de la variance de ces estimateurs. Grâce à ces résultats, le principe de Goldenshluger et Lepski nous permet d'obtenir une calibration automatique des paramètres de régularisation. Nous appliquons ensuite ce travail au recalage de densités multivariées, notamment pour des données de cytométrie de flux. Nous proposons également un test d'adéquation de lois capable de comparer deux distributions multivariées, efficacement en terme de temps de calcul. Enfin, nous exécutons une analyse statistique d'ordre deux dans le but d'extraire les tendances géométriques globales d'un jeu de donnée, c'est-à-dire les principaux modes de variations. Pour cela nous proposons un algorithme permettant d'effectuer une analyse en composantes principales géodésiques dans l'espace de Wasserstein. / This thesis focuses on the analysis of data in the form of probability measures on R^d. The aim is to provide a better understanding of the usual statistical tools on this space endowed with the Wasserstein distance. The first order statistical analysis is a natural notion to consider, consisting of the study of the Fréchet mean (or barycentre). In particular, we focus on the case of discrete data (or observations) sampled from absolutely continuous probability measures (a.c.) with respect to the Lebesgue measure. We thus introduce an estimator of the barycenter of random measures, penalized by a convex function, making it possible to enforce its a.c. Another estimator is regularized by adding entropy when computing the Wasserstein distance. We are particularly interested in controlling the variance of these estimators. Thanks to these results, the principle of Goldenshluger and Lepski allows us to obtain an automatic calibration of the regularization parameters. We then apply this work to the registration of multivariate densities, especially for flow cytometry data. We also propose a test statistic that can compare two multivariate distributions, efficiently in terms of computational time. Finally, we perform a second-order statistical analysis to extract the global geometric tendency of a dataset, also called the main modes of variation. For that purpose, we propose algorithms allowing to carry out a geodesic principal components analysis in the space of Wasserstein.
|
138 |
Avaliação de desempenho para estações de tratamento de efluentes industriais. / Performance evaluation for industrial wastewater treatments plants.Lilian Heeren Raschle 12 April 2013 (has links)
O processo produtivo industrial pode gerar uma grande quantidade de
efluentes líquidos. Esses efluentes, quando não tratados, podem poluir o solo e a
água, podendo causar grande impacto ambiental. Nesse sentido é imprescindível
que todas as indústrias que geram efluentes líquidos possuam uma estação de
tratamento. Porém, para que a estação esteja permanentemente funcionando de
acordo com seu objetivo, essa deve ser rotineiramente avaliada. Dessa forma, a
avaliação de desempenho para Estação de Tratamento de Efluentes Industriais
(ETEI) se torna uma ferramenta importante para a manutenção da eficiência da
estação, pois se justifica por procurar pontos vulneráveis da planta de tratamento
fornecendo os subsídios necessários à elaboração do diagnóstico e projetos de
adequação dos sistemas, permitindo que os efluentes tratados fiquem em
conformidade com as exigências estabelecidas pela legislação ambiental. Neste
trabalho, foi elaborada uma proposta metodológica, formada por um roteiro,
composto por níveis de questionamentos, que auxilia o avaliador na análise de
desempenho da ETEI. Complementando esse roteiro foram elaboradas algumas
listas de verificação que contribuem para guiar o avaliador em suas análises. Na
elaboração das listas, manuais desenvolvidos em diversos países foram
considerados. As listas de verificação incluem perguntas para a avaliação dos dados
gerais da indústria, para seu Sistema de Gestão Ambiental (SGA) e para alguns
sistemas e unidades operacionais da estação de tratamento. Para exemplificar um
dos níveis de questionamento do roteiro foi incluído um estudo de caso, no qual o
afluente e o efluente de uma indústria mineradora foram avaliados através da
técnica estatística multivariada Análise de Componentes Principais (ACP), para
demonstração do desempenho da estação de tratamento. O resultado da avaliação
realizada demonstrou um bom desempenho da ETEI em tratar os efluentes líquidos.
Espera-se, portanto, que este trabalho seja útil para a avaliação de desempenho em
plantas de tratamento de efluentes industriais. / The industrial production process can generate large amounts of wastewater.
These effluents, when untreated, can pollute soil and water, causing great
environmental impact. In this sense it is essential that all industries that generate
wastewater own a treatment plant. In order to keep the treatment plant permanently
functioning according to its purpose, it should be routinely evaluated. Therefore the
performance evaluation for Industrial Wastewater Treatment Plants (IWTP) becomes
an important tool for maintaining its efficiency, and justifies itself by seeking
vulnerable points on the treatment plant and providing subsidies needed to produce
diagnosis and projects to adequate the systems, allowing treated effluent to remain in
compliance with the requirements established by the environmental legislation. In this
work, a methodological proposal was designed, formed by a road map composed of
levels of questioning, which assists the evaluator in the performance analysis of
IWTP. In complement to this road map some checklists were developed to help guide
the evaluator in his analyzes. While preparing these lists, manuals developed in
several countries were considered. The checklists include questions to assess the
general data of the industry, its Environmental Management Systems (EMS) and
some systems and operations of the treatment plant. To illustrate one of the road
map questioning levels a case study was included, in which the influent and
effluent of a mining industry are evaluated by multivariate statistical technique
called Principal Component Analysis (PCA), to demonstrate the performance of
the IWTP. The result of the assessment showed a good performance by the
IWTP while treating wastewater. It is expected, therefore, that this study is useful
for evaluating the performance in plants where industrial effluents are treated.
|
139 |
Avaliação de desempenho para estações de tratamento de efluentes industriais. / Performance evaluation for industrial wastewater treatments plants.Lilian Heeren Raschle 12 April 2013 (has links)
O processo produtivo industrial pode gerar uma grande quantidade de
efluentes líquidos. Esses efluentes, quando não tratados, podem poluir o solo e a
água, podendo causar grande impacto ambiental. Nesse sentido é imprescindível
que todas as indústrias que geram efluentes líquidos possuam uma estação de
tratamento. Porém, para que a estação esteja permanentemente funcionando de
acordo com seu objetivo, essa deve ser rotineiramente avaliada. Dessa forma, a
avaliação de desempenho para Estação de Tratamento de Efluentes Industriais
(ETEI) se torna uma ferramenta importante para a manutenção da eficiência da
estação, pois se justifica por procurar pontos vulneráveis da planta de tratamento
fornecendo os subsídios necessários à elaboração do diagnóstico e projetos de
adequação dos sistemas, permitindo que os efluentes tratados fiquem em
conformidade com as exigências estabelecidas pela legislação ambiental. Neste
trabalho, foi elaborada uma proposta metodológica, formada por um roteiro,
composto por níveis de questionamentos, que auxilia o avaliador na análise de
desempenho da ETEI. Complementando esse roteiro foram elaboradas algumas
listas de verificação que contribuem para guiar o avaliador em suas análises. Na
elaboração das listas, manuais desenvolvidos em diversos países foram
considerados. As listas de verificação incluem perguntas para a avaliação dos dados
gerais da indústria, para seu Sistema de Gestão Ambiental (SGA) e para alguns
sistemas e unidades operacionais da estação de tratamento. Para exemplificar um
dos níveis de questionamento do roteiro foi incluído um estudo de caso, no qual o
afluente e o efluente de uma indústria mineradora foram avaliados através da
técnica estatística multivariada Análise de Componentes Principais (ACP), para
demonstração do desempenho da estação de tratamento. O resultado da avaliação
realizada demonstrou um bom desempenho da ETEI em tratar os efluentes líquidos.
Espera-se, portanto, que este trabalho seja útil para a avaliação de desempenho em
plantas de tratamento de efluentes industriais. / The industrial production process can generate large amounts of wastewater.
These effluents, when untreated, can pollute soil and water, causing great
environmental impact. In this sense it is essential that all industries that generate
wastewater own a treatment plant. In order to keep the treatment plant permanently
functioning according to its purpose, it should be routinely evaluated. Therefore the
performance evaluation for Industrial Wastewater Treatment Plants (IWTP) becomes
an important tool for maintaining its efficiency, and justifies itself by seeking
vulnerable points on the treatment plant and providing subsidies needed to produce
diagnosis and projects to adequate the systems, allowing treated effluent to remain in
compliance with the requirements established by the environmental legislation. In this
work, a methodological proposal was designed, formed by a road map composed of
levels of questioning, which assists the evaluator in the performance analysis of
IWTP. In complement to this road map some checklists were developed to help guide
the evaluator in his analyzes. While preparing these lists, manuals developed in
several countries were considered. The checklists include questions to assess the
general data of the industry, its Environmental Management Systems (EMS) and
some systems and operations of the treatment plant. To illustrate one of the road
map questioning levels a case study was included, in which the influent and
effluent of a mining industry are evaluated by multivariate statistical technique
called Principal Component Analysis (PCA), to demonstrate the performance of
the IWTP. The result of the assessment showed a good performance by the
IWTP while treating wastewater. It is expected, therefore, that this study is useful
for evaluating the performance in plants where industrial effluents are treated.
|
140 |
Study of Lippia alba (Mill.) N. E. Brown species and endophytic fungi associated with emphasis on the study of VOCs and biotransformations. / Estudo da espÃcie Lippia alba (Mill.) N. E. Brown e de fungos endofÃticos associados com Ãnfase no estudo de COVs e biotransformaÃÃesAiÃrta Cristina Carrà da Silva 27 July 2015 (has links)
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / This work aimed to isolate and identify endophytic fungi associated to three chemotypes of Lippia alba (Mill.) NE Brown found in Brazilian Northeast and investigate the potential of these fungi in the production of volatile organic compounds (VOCs) and in front biotransformation to organic substrates. In addition, there was a comparative study of the chemical composition of the leaves three chemotypes of L. alba detected both in essential oils obtained by hydrodistillation as the volatile constituents obtained by solid phase microextraction (SPME). The analysis and identification of volatile constituents was performed by gas chromatography coupled to mass spectrometry (GC-MS). The GC-MS data of the samples obtained by hydrodistillation and SPME were subjected to multivariate data analysis, which provided principal component analysis charts (PCA) and hierarchical cluster analysis (HCA), where it was observed that the methodology used obtaining volatile compounds can influence the classification of chemotypes made based on volatile chemically L. alba reported in the literature. The essential oils obtained from the leaves of the three chemotypes of L. alba were tested against nematicide activity, where the essential oil chemotype II had a higher potential nematicide (LD50 = 71.30 ppm). Of the six endophytic fungi isolated from L. alba leaves, only the fungi Colletotrichum sp. (chemotypes I and II) and Scopulariopsis fusca were able to produce VOCs considerably; and wherein the linalool and caryophyllene compounds produced by S. fusca have also been detected in the chemical composition leaves from L. alba chemotype I, where the fungus was isolated. The study of VOCs also pointed a biocatalytic potential for endophytic fungi from L. alba. This potential was investigated using (R)-carvona and (R)-limonene as substrates. Variables such as time and culture medium were investigated in both experiments, and the biotransformation of (R)-carvona by strains of L. alba isolated endophytes resulted in the production of three derivatives, among which one of them has not yet been reported in the literature as a product of biotransformation of carvone. Since the biotransformation of (R) led to the production of limonene nine derivatives among which four have not been reported in the literature as the limonene biotransformation products. / Este trabalho teve como objetivo principal isolar e identificar fungos endofÃticos associados a trÃs quimiotipos de Lippia alba (Mill.) N. E. Brown encontrados no Nordeste brasileiro e investigar o potencial desses fungos na produÃÃo de compostos orgÃnicos volÃteis (COVs) e na biotransformaÃÃo frente a substratos orgÃnicos. AlÃm disso, realizou-se um estudo comparativo entre a composiÃÃo quÃmica das folhas de trÃs quimiotipos de L. alba detectada tanto nos Ãleos essenciais obtidos por hidrodestilaÃÃo quanto nos constituintes volÃteis obtidos por microextraÃÃo em fase sÃlida (MEFS). A anÃlise e identificaÃÃo dos constituintes volÃteis foi realizada por cromatografia gasosa acoplada à espectrometria de massa (CG-EM). Os dados de CG-EM das amostras obtidas por hidrodestilaÃÃo e por MEFS foram submetidos à anÃlise multivariada de dados, que forneceu grÃficos de anÃlise de componente principal (ACP) e anÃlise de agrupamento hierÃrquico (AAH), onde foi possÃvel observar que a metodologia utilizada na obtenÃÃo dos compostos volÃteis pode influenciar a classificaÃÃo dos quimiotipos feita com base na constituiÃÃo quÃmica volÃtil de L. alba relatada na literatura. Os Ãleos essenciais obtidos das folhas dos trÃs quimiotipos de L. alba foram testados frente a atividade nematicida, onde o Ãleo essencial do quimiotipo II apresentou maior potencial nematicida (DL50 = 71,30 ppm). Dos seis fungos endofÃticos isolados das folhas de L. alba, somente os fungos Colletotrichum sp. (quimiotipos I e II) e Scopulariopsis fusca foram capazes de produzir COVs consideravelmente; sendo que os compostos linalol e cariofileno, produzidos por S. fusca tambÃm foram detectados na constituiÃÃo quÃmica das folhas de L. alba quimiotipo I, de onde o fungo foi isolado. O estudo dos COVs produzidos por fungos tambÃm apontou um potencial biocatalÃtico para os endÃfitos de L. alba. Este potencial foi investigado utilizando-se (R)-carvona e (R)-limoneno como substratos. VariÃveis como meio de cultivo e tempo foram investigadas em ambos experimentos, sendo que a biotransformaÃÃo da (R)-carvona por cepas de endÃfitos isolados de L. alba resultou na produÃÃo de trÃs derivados, dentre os quais um deles ainda nÃo foi citado na literatura como produto de biotransformaÃÃo da carvona. Jà a biotransformaÃÃo do (R)-limoneno levou à produÃÃo de 9 derivados, dentre os quais, 4 ainda nÃo foram relatados na literatura, como produtos de biotransformaÃÃo do limoneno.
|
Page generated in 0.0477 seconds