918 resultados para Structure-degradation relationship


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The objective of this work was to evaluate the genetic diversity, its organization and the genetic relationships within oil palm (Elaeis oleifera (Kunth) Cortés, from America, and E. guineensis (Jacq.), from Africa) germplasm using Restriction Fragment Length Polymorphism (RFLP) and Amplified Fragment Length Polymorphism (AFLP). In complement to a previous RFLP study on 241 E. oleifera accessions, 38 E. guineensis accessions were analyzed using the same 37 cDNA probes. These accessions covered a large part of the geographical distribution areas of these species in America and Africa. In addition, AFLP analysis was performed on a sub-set of 40 accessions of E. oleifera and 22 of E. guineensis using three pairs of enzyme/primer combinations. Data were subjected to Factorial Analysis of Correspondence (FAC) and cluster analysis, with parameters of genetic diversity being also studied. Results appeared congruent between RFLP and AFLP. In the E. oleifera, AFLP confirmed the strong structure of genetic diversity revealed by RFLP, according to geographical origin of the studied material, with the identification of the same four distinct genetic groups: Brazil, French Guyana/Surinam, Peru, north of Colombia/Central America. Both markers revealed that genetic divergence between the two species is of the same magnitude as that among provenances of E. oleifera. This finding is in discrepancy with the supposed early tertiary separation of the two species.

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The aim of this work was to investigate the effect of water stress on N2 fixation and nodule structure of two common bean (Phaseolus vulgaris L.) cultivars Carioca and EMGOPA-201. Plants were harvested after five and eight days of water stress. Carioca had lower nodule dry weight on both water stress periods; shoot dry weight was lower at five days water stress and did not differ from control after eight days stress. Both cultivars had lower nitrogenase activity than control after five and eight days water stress. For both cultivars, after eight days stress bacteroid membranes were damaged. Carioca presented more pronounced damage to infected tissue, with host cell vacuolation and loss of the peribacteroid membrane at five days after stress; at eight days after stress, there was degradation of cytoplasm host cells and senescence of bacteroids, with their release into intercellular spaces. Intensity of immunogold-labeling of intercellular cortical glycoprotein with the monoclonal antibodies MAC 236/265 was different for both cultivars.

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This study examines the relationship between floral structure and bud quality with the productivity and fruit shape of Gala, Fuji and Daiane apple cultivars under the mild winter conditions in Southern Brazil. Six different types of floral structures were characterized in field growing plants, according to their nature and bud size: spurs, short and long twigs with weak and vigorous buds. Variables related to the phenology and the productivity for these different structures were evaluated. Gala and Fuji cvs. showed earlier phenological development in the twigs, and cv. Daiane in the spurs. For the three cvs. the highest percentage of buds in each phenological phase was observed in the long twigs. The long twigs also showed the highest sprout and fruit set index, floral number per cluster, and leaf area in the three cvs., while the bud abortion was higher in the spurs than in the twigs. No difference was observed among the structures in cvs. Gala and Fuji regarding to the fruit shape. In the cv. Daiane, however, a tendency to higher length diameter ratio of the fruits produced by the long twigs was observed.

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Hancornia speciosa Gomes is a fruit tree native from Brazil that belongs to Apocinaceae family, and is popularly known as Mangabeira. Its fruits are widely consumed raw or processed as fruit jam, juices and ice creams, which have made it a target of intense exploitation. The extractive activities and intense human activity on the environment of natural occurrence of H. speciosa has caused genetic erosion in the species and little is known about the ecology or genetic structure of natural populations. The objective of this research was the evaluation of the genetic diversity and genetic structure of H. speciosa var. speciosa. The genetic variability was assessed using 11 allozyme loci with a sample of 164 individuals distributed in six natural populations located in the States of Pernambuco and Alagoas, Northeastern Brazil. The results showed a high level of genetic diversity within the species (e= 0.36) seeing that the most of the genetic variability of H. speciosa var. speciosa is within its natural populations with low difference among populations ( or = 0.081). The inbreeding values within ( = -0.555) and among populations ( =-0.428) were low showing lacking of endogamy and a surplus of heterozygotes. The estimated gene flow ( m ) was high, ranging from 2.20 to 13.18, indicating to be enough to prevent the effects of genetic drift and genetic differentiation among populations. The multivariate analyses indicated that there is a relationship between genetic and geographical distances, which was confirmed by a spatial pattern analysis using Mantel test (r = 0.3598; p = 0.0920) with 1000 random permutations. The high genetic diversity index in these populations indicates potential for in situ genetic conservation.

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Helicobacter pylori is an important human pathogen associated with serious gastric diseases. Owing to its medical importance and close relationship with its human host, understanding genomic patterns of global and local adaptation in H. pylori may be of particular significance for both clinical and evolutionary studies. Here we present the first such whole genome analysis of 60 globally distributed strains, from which we inferred worldwide population structure and demographic history and shed light on interesting global and local events of positive selection, with particular emphasis on the evolution of San-associated lineages. Our results indicate a more ancient origin for the association of humans and H. pylori than previously thought. We identify several important perspectives for future clinical research on candidate selected regions that include both previously characterized genes (e.g., transcription elongation factor NusA and tumor necrosis factor alpha-inducing protein Tipα) and hitherto unknown functional genes.

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Työn tavoitteena oli määrittää etähuoltokonseptin yleinen rakenne sekä selvittää asiakkaille tarjottavia modulaarisia palvelutuotteita. Aluksi selvitettiin huoltokonseptin rakennetta kirjallisuuden ja asiantuntijoiden haastattelujen avulla. Asiantuntijoiden haastattelut toteutettiin vapaamuotoisesti kysymyslistaa apuna käyttäen. Tämän lisäksi työssä pohditaan KM, CRM ja PDM rooleja etähuoltokonseptin kannalta sekä tutkaillaan etähuollon tulevaisuuden näkymiä.Diplomityössä käsitellään modulaarisuutta yleisellä tasolla. Moduularisuus on moniulotteinen termi. Usein sillä tarkoitetaan yrityksen sisäistä tuotekehityksen hallintaa. Toisaalta se voidaan nähdä myös asiakkaalle tarjottavina tuotteina ja tässä diplomityössä on keskitytty tähän puoleen. Loppuosa diplomityöstä käsittelee palvelutuotteiden tuotteistamisprosessia.Diplomityön tuloksena hahmoteltiin etähuolto konseptia ja tutkittiin mahdollisia palvelutuotteita, joita voidaan sisällyttää etähuoltokonseptiin. Tämän lisäksi toteutettiin osa tuotteistamisprosessista. Etähuollon kehittäminen on haasteellista. Haasteeksi jää tuotekehitystoiminnan ja palvelupuolen toiminnan tehostaminen, jotta tuotteita voitaisiin jo suunnittelupuolella kehittää etähuollon tarpeisiin. Kehittäminen vaatii molempien puolien aktiivista osallistumista.

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This study main purpose was the validation of both French and German versions of a Perceived Neighborhood Social Cohesion Questionnaire. The sample group comprised 5065 Swiss men from the "Cohort Study on Substance Use Risk Factors." Multigroup Confirmatory factor analysis showed that a three-factor model fits the data well, which substantiates the generalizability of Perceived Neighborhood Social Cohesion Questionnaire factor structure, regardless of the language. The Perceived Neighborhood Social Cohesion Questionnaire demonstrated excellent homogeneity (α = 95) and split-half reliability (r = .96). The Perceived Neighborhood Social Cohesion Questionnaire was sensitive to community size and participants' financial situation, confirming that it also measures real social conditions. Finally, weak but frequent correlations between Perceived Neighborhood Social Cohesion Questionnaire and alcohol, cigarette, and cannabis dependence were measured.

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We investigated the effect of benthic substratum type (sand and rocks) and nutrient supply (N and P) on biofilm structure and heterotrophic metabolism in a field experiment in a forested Mediterranean stream (Fuirosos). Rock and sand colonization and biofilm formation was intensively studied for 44 d at two stream reaches: control and experimental (continuous addition of phosphate, ammonia, and nitrate). Structural (C, N, and polysaccharide content and bacterial and chlorophyll density) and metabolic biofilm parameters (b-glucosidase, peptidase, and phosphatase enzyme activities) were analyzed throughout the colonization process. The epilithic biofilm (grown on rocks) had a higher peptidase activity at the impacted reach, together with a higher algal and bacterial biomass. The positive relationship between the peptidase activity per cell and the N content of the epilithic biofilm suggested that heterotrophic utilization of proteinaceous compounds from within the biofilm was occurring. In contrast, nutrient addition caused the epipsammic biofilm (grown on sand) to exhibit lower b-glucosidase and phosphatase activities, without a significant increase in bacterial and algal biomass. The differential response to nutrient addition was related to different structural characteristics within each biofilm. The epipsammic biofilm had a constant and high C:N ratio (22.7) throughout the colonization. The epilithic biofilm had a higher C:N ratio at the beginning of the colonization (43.2) and evolved toward a more complex structure (high polysaccharide content and low C:N ratio) during later stages. The epipsammic biofilm was a site for the accumulation and degradation of organic matter: polysaccharides and organic phosphorus compounds had higher degradation activities

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The mechanism and applications of the Fenton reaction assisted by iron-reducing phenolic compounds (IRPC) is reviewed. The presence of IRPC leads to the formation of a larger number of free radicals. The relationship between the redox potential and the IRPC structure is discussed. The effect of humic substances in the degradation of xenobiotics is also included, since these substances are able to reduce metallic ions. The natural occurrence of Fe3+/H2O2/IRPC in wood biodegradation processes, as well as their application is also discussed. The review concludes with the advantages of the Fe3+/H2O2/IRPC systems and some considerations for further process optimization and their applications at industrial levels.

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It has long been known that amino acids are the building blocks for proteins and govern their folding into specific three-dimensional structures. However, the details of this process are still unknown and represent one of the main problems in structural bioinformatics, which is a highly active research area with the focus on the prediction of three-dimensional structure and its relationship to protein function. The protein structure prediction procedure encompasses several different steps from searches and analyses of sequences and structures, through sequence alignment to the creation of the structural model. Careful evaluation and analysis ultimately results in a hypothetical structure, which can be used to study biological phenomena in, for example, research at the molecular level, biotechnology and especially in drug discovery and development. In this thesis, the structures of five proteins were modeled with templatebased methods, which use proteins with known structures (templates) to model related or structurally similar proteins. The resulting models were an important asset for the interpretation and explanation of biological phenomena, such as amino acids and interaction networks that are essential for the function and/or ligand specificity of the studied proteins. The five proteins represent different case studies with their own challenges like varying template availability, which resulted in a different structure prediction process. This thesis presents the techniques and considerations, which should be taken into account in the modeling procedure to overcome limitations and produce a hypothetical and reliable three-dimensional structure. As each project shows, the reliability is highly dependent on the extensive incorporation of experimental data or known literature and, although experimental verification of in silico results is always desirable to increase the reliability, the presented projects show that also the experimental studies can greatly benefit from structural models. With the help of in silico studies, the experiments can be targeted and precisely designed, thereby saving both money and time. As the programs used in structural bioinformatics are constantly improved and the range of templates increases through structural genomics efforts, the mutual benefits between in silico and experimental studies become even more prominent. Hence, reliable models for protein three-dimensional structures achieved through careful planning and thoughtful executions are, and will continue to be, valuable and indispensable sources for structural information to be combined with functional data.

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ABSTRACTThe term "energy nationalism" is frequently used by academic literature and media, but usually without adequate conceptual accuracy. Despite this, a set of papers deepens the discussion on the relationship between nation states and the energy industry, especially the oil sector. These papers allow identifying fundamental elements to understand the energy nationalism, either complementary or divergent between each other. Thus, this study aims at presenting an interpretation of the concept that fills the gaps left by the above mentioned literature based on a global analysis of the oil industry structure and its historical evolution since the mid-19thcentury.

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This thesis investigates two cases of Christian churches, which as a part of their mission seek to accommodate people who would otherwise not be interested in church. One of these communities consider themselves a part of the global 'emerging church' movement, and the other does not. I argue that both communities are employing what I call 'de-compartmentalization' strategy in order to adopt a pragmatic relationship with social and political issues. Furthermore I discuss the case of the emerging church community as an example of 'paraliminal community '; a concept I develop from the work of Victor Turner and Arnold van Gennep.

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Abstract . Rights jiirisprudence in Canada dates back as far as Confederation in 1867. Between this date and 1982, the organizing principle of Confederation - federalism - has kept this jurisprudence solely within the supremacy of Parliament, subject to its confines and division of powers. After 1982, however, a new constitutional organizing principle was introduced, when Prime Minister Pierre Trudeau introduced the patriation initiative, touted as the "people's package". Individual rights and freedoms were now guaranteed by the Constitution. Citizens of Canada now had a direct link to the Constitution via the Charter and there were now two significantly different organizing principles within the constitutional order widch created an unstable coexistence. This instability has led to a clash between judicially enforced Charter rights and federalism. The Charter has since had both a nationalizing and centralizing effect on Canadian federalism. This thesis explores the relationship between rights and federalism in Canada fix)m Confederation to present day by comparing the jurisprudence of pre and post Charter Canada. An analysis of Supreme Court's (and its predecessor's, the JCPC) decisions shows the profound effect the Charter has had on Canadian federalism. The result has been an undermining of federalism in Canada, with Parliamentary Supremacy replaced by Constitutional supremacy, and ultimately. Judicial Supremacy. Moreover, rights discourse has largely replaced federalism discourse. Canadians have become very attached to their Charter, and are unwilling to allow any changes to the constitution that may affect their rights as political elites discovered the hard way after the collapse of the Meech and Charlottetown Accords. If federalism is to remain a relevant and viable organizing principle in the Constitution, then governments, especially at the provincial level, must find new and iimovative ways to assert their importance within the federation.

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The effect of age on the structure and composition of isolated and purified cell walls from cultures of Choanephora cucurbitarum was investigated by microchemical analyses, visible and infrared spectrophotometry, x-ray diffractometry and electron microscopy. Qualitative evaluation revealed the presence of lipids, proteins, neutral sugars, strong alkali soluble sugars, chitin, chitosan and uronic acids in the cell walls of both the 1 and 7 day old cultures. As the mycelium aged, there was a slight but statistically significant increase in the protein content, and a pronounced rise in the chitin and neutral sugar constituents of the cell walls. Conversely, the decrease in the chitosan content during this period had the net effect of altering the chitin: chitosan ratio from near unity in the younger cultures, to a 2:1 ratio in the 7 day old cell wall samples. Glutaraldehyde-osmium fixed thin sections of the 1 day old vegetative hyphae of £. curbitarum revealed the presence of a monolayered cell wall, which upon aging became bilayered. Replicas of acid hydrolysed cell walls demonstrated that both the 1 and 7 day old samples possessed an outer layer which was composed of finely granular amorphous material and randomly distributed microfibrils. The deposition of an inner secondary layer composed of parallel oriented microfibrils in the older hypha was correlated with an increase in the chitin content in the cell wall. The significance of these results with respect to the intimate relationship between composition and structure is discussed.

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The purpose of the study was two-fold; first, the association between interpersonal coaching styles and self-determined motivation was examined, followed by the investigation of the motivation-performance relationship. Participants included 221 female Canadian Interuniversity Sport (CIS) rugby players, aged sixteen to thirty-three (M= 20.1: SD = 2.26), who reported the number of years they played CIS rugby (M= 2.3: SD = 1.37) and organized rugby (M= 5.9: SD = 2.31). Multiple and bivariate regressions were employed with autonomy-support, structure, and involvement accounting for 17%, 41 % and 22% of the variance of competence, autonomy and relatedness. The three basic needs accounted for 40% of the variance of motivation, and motivation accounted for 2% of the variance of athletes' perceptions of performance. Findings indicated that autonomy-support emerged as a predictor of all three basic needs, involvement predicted relatedness and competence, autonomy predicted motivation, and motivation predicted athletes' perception of performance.