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The biogas potential from municipal waste and agricultural residues in Hazaribagh, Dhaka city, Bangladesh : - a possible strategy to improve the energy systemHasan, A S M Monjurul January 2016 (has links)
Energy is considered as the foremost significant factor towards socio-economic growth. Due to the rapid growth of industrialization in Bangladesh, the need of energy is increasing day by day. Considering the environmental issues, sustainable solutions are needed to address the energy crisis. Energy generation from waste through biogas can be a good solution that can address both the energy demand as well as the waste management issue. The overall aim of this master thesis is to analyze Hazaribagh’s biogas potential from municipal waste and agricultural residues and estimate how much electricity that can be generated from the produced biogas. The feasible sources of Hazaribagh were considered in order to get the information that would be later on analyzed to estimate possible biogas production. The potential sources include wastes from two markets, six slaughterhouses, domestic wastes, three large-scale tanneries and two small scale tanneries, one poultry farm and three crop lands. The calculations made in this thesis to roughly estimate the amount of biogas and electricity from the described sources are done in a simple way, just to illustrate the potential. The result shows that the tannery waste has the highest potential followed by slaughterhouse waste. Furthermore, the calculations show that the tannery waste contributes most for electricity generation also followed by slaughterhouse waste. In order to implement biogas solutions, several actors should be involved like government, future owners, local people etc. Different tools like legislation, financial support etc. are also important for implementing the biogas solutions. In summary, there is a good potentiality of biogas production and electricity generation from municipal wastes and agricultural residues of Hazaribagh. Biogas solutions from waste and agricultural residues can be beneficial from both the energy and the waste management perspective.
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[pt] DESENVOLVIMENTO DE UMA CÉLULA TRIAXIAL CÍCLICA SERVO CONTROLADA E ESTUDO DA SUSCEPTIBILIDADE À LIQUEFAÇÃO DE UM RESÍDUO DA LAVRA DE MINERAÇÃO DE FERRO / [en] DEVELOPMENT OF A SERVO-CONTROLLED CYCLIC TRIAXIAL CELL AND STUDY OF THE LIQUEFACTION SUSCEPTIBILITY OF TAILINGS FROM AN IRON MINING10 January 2002 (has links)
[pt] Apresenta-se, neste trabalho, resultados de um extenso
estudo experimental de laboratório, cujos objetivos eram:
obter informações do comportamento tensão-deformação em
condições não drenadas, e verificar a susceptibilidade à
liquefação de um resíduo oriundo da lavra do itabirito
silicoso da Mina de Fernandinho, que situa-se no
Quadrilátero Ferrífero (Minas Gerais ), região com grande
concentração de minério de ferro. Para realizar o estudo de
susceptibilidade à liquefação do resíduo, foi necessário
projetar e construir um equipamento que é constituído de:
uma célual triaxial, servo-motores, válvulas para regulagem
de pressão, um microcomputador AT486, conversor D/A, um
sistema de aquisição de dados da National Instruments e
alguns acessórios que foram desenvolvidos para facilitar a
execução dos ensaios. Durante a fase de projeto e montagem
deste equipamento foi implementado um programa na linguagem
de programação C para gerenciar os ensaios. Este
equipamento possibilitou a execução dos ensaios triaxiais
cíclicos e monotônicos com trajetórias de tensões servo
controladas. Na primeira fase deste estudo foram realizados
ensaios de caracterização completa, análise mineralógica e
de microscopia eletrônica. Após a caracterização física do
material, passou-se ao estudo do comportamento tensão-
deformação e resistência com a execução de ensaios
triaxiais. Nesta fase foram executados ensaios monotônicos
e cíclicos em corpos de prova adensados isotropicamente e
anisotropicamente. Com as análises dos resultados e
entendimento do comportamento tensão deformação deste
material em condições de laboratório, concluiu-se que este
é susceptível à liquefação devido ao comportamento
colapsível e desenvolvimento elevado de poropressões.
Finalmente, propõe-se uma nova metodologia experimental
para estudar os mecanismos que levam o solo a desenvolver o
fenômeno de liquefação, tendo em vista que as metodologias
apresentadas na literatura corrente não são adequadas para
estudar este fenômeno. / [en] This work presents results of na experimental research
programme executed in the laboratory at PUC-Rio, Brazil.
The aim of this research was investigated the stress-strain
behaviour and the evaluation of the susceptibility of fine
grained tailing material from Fernandinho Mine to
liquefaction. This mine is at Quadrilatero Ferrífero (Minas
Gerais - Brazil), region with one of the largest sources of
iron ore in Brazil.In order to study the susceptibility to
liquefaction of tailing material an servocontrolled
triaxial device was developed. This device were composed
by: triaxial cell, servo-motors,pressure regulators,
microcomputer, one digital analogy convert of, one analogy
digital convert developed in the laboratory at PUC-Rio and
other accessories. During the development of the device,
one software to control all the trajetories was
implemented. Using this device some cyclic and monotonic
triaxial tests were carried out.Complete characterization,
mineralogical and eletronic microscope analysis were
carried out in the preliminary steps of this research.
After this, an extensive programme of triaxial tests were
carried out in order to determine the failure envelope,
stress-strain behaviour and liquifiction resitance of the
tailing material.A colapsive behavior of the tested
material was observed at small strain and stress
conditions. Another important observation was the high
level of poropressure development,suggesting that this
material is susceptible to liquefaction in special
conditions.Finally, based on the test results, a new
methodology is proposed to investigate soils when submitted
to undrained conditions.
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Integration eines Antidoping-Informationsmoduls in VETIDATA und Bewertung der Antidoping-Bestimmungen am Beispiel von AlkaloidenHertzsch, Robert 23 May 2018 (has links)
Einleitung:
Im Pferdesport kann es heutzutage durch die starke Verbesserung der Sensitivität der eingesetzten Nachweismethoden bereits durch die Aufnahme von mit dopingrelevanten Stoffen kontaminiertem Futter zu positiven Anti-Doping-Proben kommen. Dies trifft insbesondere für Alkaloide zu. Wird nach dem tiermedizinisch begründeten Einsatz von Arzneimitteln bei Sportpferden keine ausreichende Frist beachtet, können auch hierdurch Fälle unabsichtlichen Dopings auftreten.
Ziele der Untersuchung:
Erstes Ziel dieser Arbeit war es, die zur Verhinderung unabsichtlichen Dopings nach Arzneimittelanwendung durch den Tierarzt benötigten Informationen in den webbasierten Veterinärmedizinischen Informationsdienst für Arzneimittelanwendung, Toxikologie und Arzneimittelrecht (VETIDATA) zu integrieren. Dafür sollten insbesondere die Regel der Deutschen Reiterlichen Vereinigung e.V. (FN) und des Weltpferdesportverbandes Fédération Équestre Internationale (FEI) berücksichtigt werden. Die International Federation of Horseracing Authorities (IFHA) hat im Jahr 2014 Rückstandshöchstmengen für die Kontrolle bestimmter dopingrelevanter Futtermittel-kontaminanten festgelegt. Die wissenschaftliche Untersuchung und Validierung der International Residue Limits (IRL) der Alkaloide Atropin, Scopolamin, Morphin, Koffein und Theophyllin war das zweite Ziel dieser Untersuchung.
Material und Methoden:
Zunächst wurde in VETIDATA ein Anti-Doping-Informationsmodul integriert. Zur Speicherung der für die Informationsanzeige benötigen Daten wurden Datenbanktabellen entwickelt und mit dem VETIDATA-System verknüpft. Zur Anzeige der Information wurde anschließend ein Prototyp der Darstellungslogik mit der Programmiersprache PHP erstellt. Dieser diente als Grundlage für die Aufnahme des Anti-Doping-Informationsmoduls in die Webseite von VETIDATA. Zur Bewertung der IRLs der untersuchten Alkaloide wurde eine systematische Metaanalyse durchgeführt. Zuerst wurden die Literaturdatenbanken PubMed, Web of Science, CABI und die Publikationsdatenbanken der deutschsprachigen veterinärmedizinischen Fakultäten und Hochschulen nach potentiell relevanten Veröffentlichungen durchsucht. Nach Anwendung von Inklusionskriterien, die z.B. Alter, Tierart, verabreichten Stoff und dessen Dosis, Applikationsweg und Angaben zu pharmakokinetischen Parametern in den Publikationen berücksichtigten, wurden die für diese Arbeit geeigneten Studien identifiziert und anschließend die darin enthaltenen pharmakokinetischen Daten extrahiert. Die Parameter Clearance, Verteilungsvolumen und Halbwertszeit wurden statistisch auf das Vorliegen einer Normalverteilung geprüft und der jeweilige Mittelwert, das 95%-Konfidenzintervall sowie die Standardabweichung wurden berechnet. Dosis-Urinkonzentrationsverhältnisse wurde mittels linearer Regressionsanalysen untersucht. Diese Daten dienten als Grundlage für die Berechnung geeigneter Grenzwerte mithilfe von in der Literatur beschriebenen Methoden.
Ergebnisse:
Das erstellte Anti-Doping-Informationsmodul beinhaltet Angaben zum Status von 863 Wirkstoffen nach den Regeln der FEI und der FN. Diese umfassen alle in Deutschland in für Pferde zugelassenen Arzneimitteln enthaltenen wirksamen Substanzen sowie alle weiteren bei nicht von der Lebensmittelgewinnung ausgeschlossenen Pferden nach geltendem Recht anwendbaren Stoffe. Diese Informationen können vom Nutzer auf VETIDATA an unterschiedlichen Stellen abgerufen werden und sind direkt mit den für Pferde zugelassenen Tierarzneimitteln verknüpft. Für die Durchführung der Metaanalyse der IRLs wurden 1173 potentiell nutzbare Studien in der Literatur identifiziert. Nach Anwendung der Inklusionskriterien konnten Daten aus 42 Studien in die Metaanalyse inkludiert werden. Diese erlaubten eine statistische Untersuchung pharmakokinetischer Parameter für Morphin, Theophyllin und Koffein, nicht aber für Atropin und Scopolamin. Eine lineare Regressionsanalyse der Dosis-Urinkonzentrationsverhältnisse war bei Scopolamin und Koffein möglich. Die Ergebnisse dieser Untersuchungen erlaubten in Verbindung mit nicht statistisch bearbeiteten Daten aus den inkludierten Studien die Anwendung einer Methode zur IRL-Bewertung von Atropin und Scopolamin, von zwei Methoden für Morphin und Theophyllin und von drei Methoden für Koffein. Dabei zeigte sich, dass von den untersuchten Stoffen nur die IRLs von Atropin und Theophyllin in geeigneter Höhe festgelegt wurden, um positive Dopingbefunde durch die Aufnahme von geringgradig kontaminierten Futtern zu verhindern. Die IRLs von Morphin, Theophyllin und Koffein sind geeignet, das Bestehen eines relevanten pharmakologischen Effekts nach systemischer Anwendung dieser Stoffe auszuschließen, was für Atropin und Scopolamin aufgrund der mangelhaften Datenlage nicht sicher beurteilt werden konnte. Ein eventuell vorhandener pharmakologischer Effekt nach lokaler Anwendung kann durch die IRLs von Atropin und Scopolamin nicht sicher ausgeschlossen werden. Die Eignung des IRL von Morphin für diesen Zweck wurde als fraglich beurteilt, während diese Fragestellung für Koffein und Theophyllin nicht relevant war. Das Fehlen eines IRL für den aus Koffein bzw. Theophyllin gebildeten aktiven Metaboliten Paraxanthin wurde als erheblicher Mangel am bestehenden IRL-System erkannt.
Schlussfolgerungen:
Die Integration des Anti-Doping-Informationsmoduls in VETIDATA ermöglicht Tierärzten einen einfachen und schnellen Zugang zu den für die Arzneimittelanwendung bei Sportpferden benötigten Informationen. Das IRL-System der IFHA erfüllt in seiner aktuellen Form nicht alle Anforderungen, die im Sinne eines fairen und dopingfreien Pferdesports zu stellen sind. Geeignete Änderungen an diesem System könnten eine Verbesserung der Einschätzung für Koffein und Theophyllin ermöglichen. Systematische Mängel des IRL-Systems erfordern einen strukturell anderen Ansatz zur Kontrolle der auch lokal wirksamen Stoffe Atropin, Scopolamin und Morphin.
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The impact of gold and coal mine residue on water resources in the Roodepoort and Newcastle areasMorokane, Tebogo Molefe Shadrack 08 May 2012 (has links)
Large quantities of tailings are produced during gold and coal mining activities. These tailings consist of ash dumps, waste rock dumps, in-pit deposits and any other heap, pile or accumulation of residue in the tailings or slimes dams. It has been reported that these tailings can have a significant impact on water quality in the vicinity of gold and coal residues in South Africa. Water quality deterioration in the vicinity of gold and coal mines in the Johannesburg and other areas has been reported. However, little information is available on the potential impact of residues on water quality near Roodepoort and Newcastle where gold and coal, respectively, are mined. The objective of this investigation was therefore to determine the potential impact of gold and coal mine residues on the environment in the vicinity of Roodepoort and Newcastle. Secondary objectives were to identify the metal constituents of gold and coal mine residues, to evaluate and define the current knowledge with regard to the short-term water quality impact of gold and coal residues in terms of concentration of metals leaching from the residues, to assess the potential impact of gold and coal tailings on the water environment within the study areas and to suggest methods to prevent pollution from taking place. Acid Base Accounting (ABA), Toxicity Characteristics Leaching (TCLP), Acid Rain Leaching Procedure (ARLP) and Inductively Plasma Coupled – Mass Spectrometry (IPC-MS) were used as tools to determine the potential impact of gold and coal tailings on the environment. Acid Base Accounting comprises two components that show the potential of the mine residue to produce acid mine drainage, that is, the total sulphur and the net neutralisation potential (NNP). It has been reported that any pyrite mine residue containing more than 0.5% total sulphur may generate acid mine drainage. Mine residues with a net neutralisation potential of less than zero ppt CaCO3 produce acid drainage. The acid base accounting results show that the gold and coal mine residues contain sulphur which has the potential to produce acid mine drainage. Lithium (Li), sodium (Na) magnesium (Mg), aluminium (Al), potassium (K), calcium (Ca), iron (Fe), manganese (Mn) and nickel (Ni) were identified to be present in the gold mine residue. The concentrations of some of the metals that leached from the gold residue according to the TCLP tests were as follows: Al (22 mg/L); Ca (242 mg/L); Fe (29 mg/L); Mn (88 mg/L) and Ni (87 mg/L). The metals that leached from the gold residue according to the ARLP results were as follows: Na (43 mg/L); Al (169 mg/L); Ca (246 mg/L); Fe (771 mg/L); Mn (16 mg/L) and Ni (11 mg/L). Higher concentrations of metals generally leached from the gold residue with the ARLP test than with the TCLP test. The sulphate concentration up-stream of the gold residue was determined at 225 mg/L. This concentration increased to 3 490 mg/L at the decanting point and to 11 577 mg/L downstream of the decanting point. The surface and possibly groundwater are therefore polluted with sulphates. Lithium (Li), sodium (Na), magnesium (Mg), aluminium (Al), potassium (K), calcium (Ca), iron (Fe), manganese (Mn) and nickel (Ni) were identified to be present in the coal mine residue. The concentrations of some of the metals that leached from the coal residue according to the TCLP tests were as follows: Al (3 mg/L); Ca (56 mg/L); Fe (0.21 mg/L); Mn (1 mg/L) and Ni (0.082 mg/L). The metals that leached from the coal residue according to the ARLP test results were as follows: Na (3 mg/L); Al (15 mg/L); Ca (136 mg/L); Fe (0.91 mg/L); Mn (1 mg/L) and Ni (0.07 mg/L). Higher concentrations of metals generally leached from the coal residue with ARLP test than with the TCLP test. The sulphate concentration up-stream of the coal residue was determined at 26 mg/L. This concentration increased to 3 615 mg/L at the decanting point and to 6 509 mg/L downstream of the decanting point. The surface and possibly groundwater are therefore polluted with sulphate. The upstream Na (26 mg/L), Ca (41 mg/L), Fe (0,02 mg/L), Mn (3 mg/L) and Ni (0.065 mg/L) concentrations were low in the case of the gold residues. These concentrations at the decanting point were: Na (289 mg/L); Ca (266 mg/L); Fe (0.2 mg/L); Mn (0.01 mg/L) and Ni (2 mg/L). Fifty metres downstream these concentrations were: Na (140 mg/L); Ca (389 mg/L); Fe (722 mg/L); Mn (395 mg/L) and Ni (15 mg/L). There was a significant increase in the metal concentration from up-stream of the gold residue, to the decanting point and further downstream of the gold residue. The surface and possibly ground water are therefore polluted by the metals leaching from the gold residue. The upstream Na (5 mg/L), Ca (8 mg/L), Fe (0,12 mg/L), Mn (0.015 mg/L) and Ni (0.05 mg/L) concentrations were low in the case of the coal residues. These concentrations at the decanting point were: Na (189 mg/L); Ca (337 mg/L); Fe (68 mg/L); Mn (13 mg/L) and Ni (0.06 mg/L). Fifty metres downstream these concentrations were: Na (65 mg/L); Ca (129 mg/L); Fe (0.48 mg/L); Mn (5 mg/L) and Ni (0.06 mg/L). There was a significant increase in the metal concentration from up-stream of the coal residue, to the decanting point and further downstream of the coal residue. The surface and possibly ground water are therefore polluted by the metals leaching from the coal residue. The gold and coal mine residues are polluting the surface and possibly ground water. Therefore, in order to ameliorate the current status within the Roodepoort and Newcastle catchments, mitigation and management measures such as that the residues should be covered and capped with soil material that would prevent infiltration of the oxygen and rain water into the soil, are recommended. A more comprehensive water quality analysis of the surroundings of the residues is also suggested to be able to better quantify the extent of the problem. Copyright / Dissertation (MSc)--University of Pretoria, 2011. / Chemical Engineering / Unrestricted
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Mass Spectrometry-Based Identification of Ceramic-Bound Archaeological Protein Residues: Method Validation, Residue Taphonomy, and ProspectsBarker, Andrew Lewis 12 1900 (has links)
Despite the variety of successful reports of the preservation, recovery, and identification of archaeological proteins in general, there are few positive reports regarding mass spectrometry-based identification of ceramic-bound proteins. In large part, this shortage is due to the lack of consideration for the unique taphonomic histories of such residues and, in general, methods development. Further, because negative results are rarely published, there is no baseline to which results can be compared. This paper attempts to address these challenges via a multi-pronged approach that uses mass spectrometry and complementary approaches to evaluate ceramic-bound protein preservation in both controlled, actualistic experiments, and in archaeological artifacts. By comparing the results obtained from protein-spiked, experimentally-aged ceramic to those obtained from both faunal and ceramic archaeological materials, an enhanced perspective on protein preservation and subsequent recovery and identification is revealed. This perspective, focusing on taphonomy, reveals why negative results may be the norm for ceramic artifacts when non-targeted methods are employed, and provides insight into how further method development may improve the likelihood of obtaining positive results.
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RESIDUE CLASS-BASED COMMON INTEREST NETWORK: A NOVEL APPROACH IN DESIGNING A LOW DIAMETER, TWO-LEVEL HIERARCHICAL, STRUCTURED P2P NETWORK ARCHITECTURE AND COMMUNICATION PROTOCOLSKaluvakuri, Swathi 01 September 2021 (has links) (PDF)
The main objective of this research is to build an interest based peer – to – peer network which is structured yet non-DHT. Maintaining DHTs is a complex task and needs substantial amount of effort to handle the problem of churn. So, the major challenge facing such architectures is how to reduce this amount of effort while still providing an efficient data query service. The rationale behind choosing non- DHT based interest based network is that users sharing common interests are likely to share similar contents, and therefore searches for a particular type of content is more efficient if peers likely to store that content type are neighbors. We have used a mathematical model based on modular arithmetic, specifically residue class (RC), to design a two-level structured architecture. To the best of my knowledge, there does not exist any such work that has used this mathematical model.
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[pt] DESENVOLVIMENTO DE FLUXOGRAMA PARA BENEFICIAMENTO DE RESÍDUOS DA CONSTRUÇÃO CIVIL / [en] DEVELOPMENT OF FLOW CHART FOR THE IMPROVEMENT OF WASTE CONSTRUCTIONRICARDO FREDERICO ARAUJO LANZELLOTTI 21 December 2005 (has links)
[pt] Qualquer atividade humana é por natureza geradora de
resíduos. As atividades
industriais são um dos grandes geradores de resíduos,
sejam sólidos, líquidos
ou gasosos, os quais devem ser gerenciados corretamente
visando à
minimização de custos e redução do potencial de geração de
impactos
ambientais. De acordo com as Leis 6.938/81, que institui a
Política Nacional do
Meio Ambiente, e a 9.605/98, que trata dos crimes
ambientais, a
responsabilidade pela reparação de qualquer dano
ambiental, independente do
fato gerador, a empresa será chamada para remediar
qualquer passivo gerado
devida à má gestão de resíduos, onde a responsabilidade da
empresa não cessa
quando estes deixam suas instalações, incluindo sua
destinação final. Desta
forma a reciclagem de materiais da construção civil deve
ser subsidiada por um
programa bem mais amplo, onde envolva além do
processamento dos resíduos,
a recuperação de áreas degradadas com limpeza; a
implantação de áreas
destinadas à recepção de materiais oriundos da construção
civil, reduzindo a
necessidade de áreas públicas usadas como aterro. O
desenvolvimento de
técnicas que visem a redução dos impactos ambientais
causados tanto pela
geração de resíduos como pela extração de agregados
naturais, são de
significativa importância uma vez que a legislação vigente
indica este caminho
como o único a ser seguido. Desta forma desenvolveu-se um
fluxograma para o
beneficiamento do resíduo da construção civil visando a
produção de agregado
reciclado miúdo a ser utilizado na confecção de argamassas
e concretos em
substituição, total ou parcial, da areia sem perdas
significantes na resistência a
esforços mecânicos. / [en] Any human activity is by nature generating of residues.
The industrial activies are
one of the great generators of residues, be solid, liquids
or gaseous, which
should be correctly management seeking to minimize costs
and reduction of the
potential generation in environmental impacts. In
agreement with the law
6.938/81, that establish the National Politics of the
environmental, and the
9.605/81, that´s treats of the environmental crimes, the
responsibility for the
repair of any environmental damage, independent of the
generating fact, the
company will be called to remedy any passive one generated
owed to the bad
administration of residues, where the responsibility of
the company doesn´t
cease when these leave your facilities, including your
final destination. This way
the recycling of materials construction should be
subsidized by a much wider
program, where it involves besides the processing of the
residues, the recovery
areas degraded with cleaning; the implantation of areas
destined to the
reception of materials originating from constructions,
reducing the need public
areas used as embankment. The development of techniques
that`s seek the
reduction of the environmental impacts caused so much by
the generation of
residues as for the extraction of natural aggregate, they
are of significant
importance once the effective legislation indicates this
only way to be
proceeded. The development of the improvement waste
construction seeking the
production of small recycled aggregate to be used in
making of mortars and
concretes in substitution, total or partial, of the sand
without significant losses in
the resistance to mechanical efforts.
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Analysis of Biological Networks by Graph Theory-based Methods / 生物情報ネットワークのグラフ理論に基づく解析法Li, Ruiming 23 March 2023 (has links)
京都大学 / 新制・課程博士 / 博士(情報学) / 甲第24730号 / 情博第818号 / 新制||情||138(附属図書館) / 京都大学大学院情報学研究科知能情報学専攻 / (主査)教授 阿久津 達也, 教授 山本 章博, 教授 岡部 寿男 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
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Effects of Crop Residue Quality and Nitrogen Fertilization on Priming of Soil Organic Carbon Mineralization / 土壌有機物無機化におけるプライミング効果に及ぼす作物残渣の質と窒素施肥の影響Ma, Qian 25 January 2021 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(地球環境学) / 甲第22905号 / 地環博第206号 / 新制||地環||40(附属図書館) / 京都大学大学院地球環境学舎地球環境学専攻 / (主査)教授 舟川 晋也, 准教授 渡邉 哲弘, 准教授 舘野 隆之輔 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM
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Quantitative Studies of Amyloidogenic Protein Residue Interaction Networks and Abnormal Ammonia Metabolism in Neurotoxicity and DiseaseGriffin, Jeddidiah 01 August 2018 (has links) (PDF)
Investigating similarities among neurological diseases can provide insight into disease processes. Two prominent commonalities of neurological diseases are the formation of amyloid deposits and altered ammonia and glutamate metabolism. Computational techniques were used to explore these processes in several neurological diseases. Residue interaction networks (RINs) abstract protein structure into a series of nodes (representing residues) and edges (representing connections between residues likely to interact). Analyzing the RINs of monomeric forms of amyloidogenic proteins for common network features revealed similarities not previously known. First, amyloidogenic variants of lysozyme were used to demonstrate the usefulness of RINs to the study of amyloidogenic proteins. Next, I compared RINs of amyloidogenic proteins with randomized control networks and a group of real protein controls and found similarities in network structures unique to amyloidogenic proteins. The use of 3D structure data and network structure data of amyloid-beta (1-42) (Abeta42) in a hydrophobic, membrane-mimicking solvent led to the identification of an interaction between Val24 and Ile31 as potentially involved in preventing Abeta aggregation. Since Abeta causes oxidative damage, since the ammonia metabolism enzyme glutamine synthetase is particularly susceptible to oxidative damage, and since glutamate plays a central role in neuronal function, I expanded my research to include the study of ammonia and glutamate metabolism in neurological diseases. A computational model of the effects of the interactions between the amount of dietary protein and the activities of ammonia metabolism enzymes on blood and brain ammonia levels supports potentially important roles for these enzymes in the protection of neural function. Next, I reviewed the role of amino acid catabolism in Alzheimer’s disease (AD). Common tissue pathology and the ability of memantine, an NMDA receptor antagonist, to relieve symptoms in patients and animal models of AD, major depressive disorder (MDD), and type 2 diabetes (T2D) further support a role for ammonia and glutamate metabolism in disease. Lastly, I found that single nucleotide polymorphisms (SNPs) in select ammonia metabolism genes are associated with these three diseases. The results presented in this dissertation demonstrate that investigating neurological diseases using computational approaches can provide great insight into the common underlying pathologies.
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