For flawless translation of mRNA sequence into protein, tRNAs must undergo a series of essential maturation steps to be properly recognized and aminoacylated by aminoacyl-tRNA synthetase, and subsequently utilized by the ribosome. While all tRNAs carry a 30 -terminal CCA sequence that includes the site of aminoacylation, the additional 50 -G-1 position is a unique feature of most histidine tRNA species, serving as an identity element for the corresponding synthetase. In eukaryotes including yeast, both 30 -CCA and 50 -G-1 are added post-transcriptionally by tRNA nucleotidyltransferase and tRNAHis guanylyltransferase, respectively. Hence, it is possible that these two cytosolic enzymes compete for the same tRNA. Here, we investigate substrate preferences associated with CCA and G-1-addition to yeast cytosolic tRNAHis, which might result in a temporal order to these important processing events. We show that tRNA nucleotidyltransferase accepts tRNAHis transcripts independent of the presence of G-1; however, tRNAHis guanylyltransferase clearly prefers a substrate carrying a CCA terminus. Although many tRNA maturation steps can occur in a rather random order, our data demonstrate a likely pathway where CCA-addition precedes G-1 incorporation in S. cerevisiae. Evidently, the 30 -CCA triplet and a discriminator position A73 act as positive elements for G-1 incorporation, ensuring the fidelity of G-1 addition.

Citations allow researchers to define relationships across articles and develop arguments by building on the work of others. This study explores citation of theory symbols in Instructional Design and Technology (IDT) academic articles. The term theory symbol is used to define a concept that, after its original publication, is subsequently incorporated by later writers through citation. Exploring the citation history of the seminal publications makes it possible to trace theory symbol use over time and thus to trace its dissemination in the field. A typology of theory symbol use in IDT academic publication is developed through a citation context analysis (CCA) of a sample of articles published in Educational Technology Research and Development (ETRD) and its predecessor journals (1953–2012) which incorporate theory symbols through citation. This analysis contributes to an understanding of how theory has shaped IDT disciplinary knowledge and augments discourse analysis and bibliometrics by examining the context in which theory is incorporated into academic publication. / Ph. D.

Šiame darbe nagrinėjami netiesiniai daugdarų atpažinimo metodai ir daugiamačių duomenų projekcijos metodai. Siūloma jais spręsti keliais laisvės laipsniais besisukančio objekto orientacijos radimo problemą. Aprašomi MDS, Trianguliacijos, Sammon, RPM, mRPM, CCA, PCA, LLE, LE, HLLE, LTSA, SMACOF ir Isomap metodai. Su kai kuriais iš jų atliekami web-kamera gautų galvos atvaizdų tyrimai. Isomap algoritmo pagrindu sukuriama programinė įranga ir su ja taipogi atliekami galvos orientacijos tyrimai. / This paper deals with Analysis of non-linear manifold learning methods and multidimensional data projection methods. It is proposed use them in solving problem of detection of orientation of object, moving in few degrees of freedom. Methods described: MDS, triangulation, Sammon, RPM, mRPM, CCA, PCA, LLE, LE, HLLE, LTSA, SMACOF and Isomap. Some of them are used to analyze head images acquired by webcam.. Application is created which is then used to analyze head orientation by implementing Isomap method.

Alloying aluminum offers the possibility of creating low-density high-entropy alloys (HEAs). Several studies that focus on the system AlCoCrFeNiTi differ in their phase determination. The effect of aluminum on the phase composition and microstructure of the compositionally complex alloy (CCA) system AlxCoCrFeNiTi was studied with variation in aluminum content (molar ratios x = 0.2, 0.8, and 1.5). The chemical composition and elemental segregation was measured for the different domains in the microstructure. The crystal structure was determined using X-ray diffraction (XRD) analysis. To identify the spatial distribution of the phases found with XRD, phase mapping with associated orientation distribution was performed using electron backscatter diffraction. This made it possible to correlate the chemical and structural conditions of the phases. The phase formation strongly depends on the aluminum content. Two different body-centered cubic (bcc) phases were found. Texture analysis proved the presence of a face-centered cubic (fcc) phase for all aluminum amounts. The hard η-(Ni, Co)3Ti phase in the x = 0.2 alloy was detected via metallographic investigation and confirmed via electron backscatter diffraction. Additionally, a centered cluster (cc) with the A12 structure type was detected in the x = 0.2 and 0.8 alloys. The correlation of structural and chemical properties as well as microstructure formation contribute to a better understanding of the alloying effects concerning the aluminum content in CCAs. Especially in the context of current developments in lightweight high-entropy alloys (HEAs), the presented results provide an approach to the development of new alloy systems.

Savanna woodlands are vitally important in providing ecological services (e.g. erosion protection, micro-climate) and economic services (e.g. timber, food, fodder non-wood products, and wild-life habitats) that sustain local livelihoods and national economies. Increasing demands and the need for sustainable savanna woodland resource management requires that the ecological, economic, social and cultural values of these resources be explored and brought to the attention of decision makers and the general public. The identification and better understanding of the structure and dynamics of woodland community types, patterns of species distribution and quantitative properties of their diversity is important to the conservation and sustainable management of these woodlands. This study seeks to contribute to a better understanding of Nakasongola woodland community types, species diversity patterns and environment correlates, natural regeneration processes (i.e. sprouting and seedling establishment) and identifying livelihood strategies adopted by households, woody species utilised, and the contribution of charcoal production to household livelihoods. Data on vegetation and environmental variables were collected using 75 rectangular 20 x 50 m (0.1 ha) plots. Data on land use and land cover changes, and relevant associated socio-economic parameters were collected through the analysis of multi-temporal satellite imagery and field observations, as well as interviews of local households and key informants. The basic major livelihood activities for the rural households in this savanna dryland are charcoal production, subsistence crop cultivation and livestock grazing. However, it, sometimes, includes various combinations of activities, i.e. charcoal production and subsistence crop cultivation for both food and cash, and livestock keeping for income generation through selling the livestock products such as milk and, sometimes, the whole animal. At least 24 woody species, including fruit trees (Mangifera indica and Artocarpus heterophyllus), are frequently harvested, including 16 species that are considered the most utilized for charcoal production. Charcoal production, being the major source of income to the rural households, contributes on average US$ 259 ± 46 (S.E.) per household annually. There were significant differences in charcoal production (Kruskal-Wallis; H = 31.42, p < 0.0001), producer sale prices per bag of charcoal (H = 35.62, p < 0.0001), and annual incomes from charcoal production (H = 32.44, p < 0.0001) per households across the 8 sub-counties. Most of the youth (≤ 20 years old) derive their livelihoods from charcoal production, a small amount of trade, offering labour services, livestock keeping, fishing, bee keeping and earth brick making. Charcoal production, livestock keeping and hunting are carried out particularly by men, whereas, crop cultivation, and collection of fire wood, medicinal plants and fruits are carried out, mainly, by women. However, men are also engaged in cultivation only during the rainy seasons. There have been significant land cover changes in the area during the period 1984 to 2001, resulting in a 64% decrease in dense woodland cover, and an 80% increase in areas under cultivation/settlements. These changes are attributed to significant spatial expansion in agriculture increased commercialisation of charcoal production, grazing and human population growth. A total of 44,195 (5,893 plants/ha) woody plants representing 99 species in 67 genera and 31 families were recorded. The most species rich families were Mimosaceae (13), Rubiaceae (9), Moraceae (7), Euphorbiaceae (7), Anacardiaceae (6), Combretaceae (5) and Verbenaceae (5). Density of woody species differed significantly (F2, 72 = 6.3, P < 0.003) among land uses, being higher under charcoal production (7,131 ± 755 plants/ha) and cultivation (6,612 ± 665) areas and significantly lower under grazing lands (4,152 ± 525). Community species composition differed significantly (Global RANOSIM = 0.14, p = 0.001) among land use types. All measures of beta-diversity (spatial “turnover” in species composition) showed consistently higher beta-diversity in the grazing land use (βW = 3.1; βT = 3.1), followed by cultivation (βW = 2.8; βT = 3.0) and charcoal production (βW = 2.7; βT = 2.8), suggesting a more heterogeneous spatial distribution of species in the grazing lands. This suggests that variations in the composition and diversity of woody species are to a great extent influenced by land use type and anthropogenic disturbances in this region. Basal area of woody species differed significantly (F2, 72 = 12.0, P < 0.0001) among land uses, being highest under cultivation and charcoal production and significantly lower under grazing. Woody plant density differed (F2,72 = 6.3, P = 0.003) across landuses, being highest under charcoal production and cultivation and significantly lower under grazing. The species that contributed most to both basal area and density across all the land uses were Combretum collinum and Combretum molle. However, different species contributed the next most i.e. Piliostigma thonningii for grazing; Albizia zygia and Harrisonia abyssinica for cultivation and Vepris nobilis for charcoal production areas. For both basal area and abundance of all woody species, the total variance in species-environmental factor relations (for the combined first four canonical axes) was higher than 50%, suggesting a relatively strong influence of the measured environment variables on species composition and distributions. The CCA points to a significant influence of soil Ca2+ and Mg2+ in association with grazing on gradients in the composition and structure of woody species in the savanna woodland of Nakasongola. Resprouting was generally common among the woody species. A total of 2,595 stumps, representing 74 species in 31 families were recorded from all plots. Of these, 98.3% resprouted and were identified to species level. Density of both stumps and total resprout differed significantly (p < 0.05) among the land uses, being higher in charcoal production areas than in grazing and cultivation land uses. For the overall pooled data, resprouts per stump differed significantly among land uses (F2, 456 = 7.75, p = 0.0005), being highest in charcoal production (mean ± S.E.; 14 ± 1) and cultivation (13 ± 1) land uses and lowest under grazing areas (10 ± 1). Generally, the mean number of resprouts per stump increased with increasing stump basal diameter (BD), being highest for BD size class > 41 cm. In relation to stump height, the highest mean resprouts/stump was found on stumps with heights ranging from 0.31- 0.40 m. Based on pooled species data, regression analyses showed weakly significant negative relationships between BD of leading resprouts and number of resprouts/stump (r2 = 0.123, p < 0.0001) and between height of leading resprouts and number of resprouts/stump (r2 = 0.068, p < 0.0001). Density of seedlings of woody species differed significantly among land use types (ANOVA; F2, 72 =5.9, p = 0.004), being highest for cultivation (3,162 ± 440 individuals ha-1), followed by charcoal production (2,416 ± 295 ha-1) and lowest for grazing (1,629 ± 205 ha-1). Composition of seedlings differed significantly among land use types (Global RANOSIM = 0.119, p = 0.001). The distributions and densities of some seedlings were explained by gradients in environmental variables, with edaphic factors (i.e. Ca2+, Mg2+, K+ and organic matter) and charcoal production being the most important. The first two axes of the Canonical Correspondence Analysis (CCA) explained 41.9% of the variance in species – environmental relations and were a reflection of edaphic and charcoal production land use gradients. All of the 16 highly utilized species were well represented in both the juvenile and adult classes, with gradually declining number of individuals with increasing stem size-class. This indicates that most of these species have high regeneration potential. Juvenile:adult tree ratios >1 and negative DSCD slopes indicate good recruitment and probably successful regeneration for these species. The study revealed land cover changes mainly in the dense and medium dense woodlands, reflected by the increase in open woodland, grasslands and cultivation/settlements. These trends threaten the livelihoods of local communities who are entirely dependent on these natural resources. Sustainable management will require the establishment of suitable integrated community-based institutions and management practices, with support from all key stakeholders (i.e. National Forest Authority (NFA)) and local communities. Maintenance of savanna woodland resources and other ecosystem services essential for human well-being will require an effective legal framework to prevent over-exploitation and give incentives for the protection of the fragile savanna woodland vegetation. An appropriate savanna woodland management policy will be required to guide changes in land use that accommodate the requirements of land users, aided by targeted conservation efforts to all woody plants and particularly for the highly utilized species for charcoal production as well as the multipurpose species. In addition, there is urgent need to build local capacity for improved harvesting and utilization of these tree species. This can be achieved through equipping local users with up to date information as well as observing the existing skills.

Force deployment and optimal resource allocation has been an area of considerable research interest in conventional warfare. In the modern scenario, with significant advances in technology related to communication and computation, sophisticated decision-making in these situations has become feasible. This has generated renewed interest in formulating decision-making problems in these areas and seeking optimal solutions to them. This thesis addresses one such problem in which the defending forces need to optimally Partition their resources between several attacking forces of differing strengths. The basic model considered for resource allocation is Lanchester attrition models. Lanchester models are deterministic differential equations that model attrition to forces in convict. In this thesis we address a resource allocation problem where the resource allocation is done using different approaches. First, we developed a (2,1) model using the Lanchester square law model for attrition. For this model we assumed that the attacking force consists of two types of forces and the defending force consists of only one type of force. The objective is to optimally partition the defending force against the two attacking forces so as to maximize the surviving defending force strength and to minimize the attacking force strength. The objective function considered in this thesis is the weighted sum of the surviving defending force strength and the destroyed attacking force strength. We considered a resource allocation problem in which allocation of resources are done using four different approaches. The simplest is the case when allocation is done initially and no further action is taken Iv Abstract v (Time Zero Allocation (TZA)). For the TZA allocation scheme, when any of attacking forces gets destroyed, the corresponding defending force which was engaging that attacking force will stop interacting further. This situation rarely happens in reality. Hence to make this scenario more realistic, we considered another allocation scheme in which allocation is followed by redistribution of resources depending on certain decisive events (Time Zero Allocation with Redistribution (TZAR)). In TZA and TZAR schemes, the allocation of defending force is done only at the initial time. Deviating from this assumption, we considered another allocation scheme in which a constant allocation ratio is used continuously over time till the end of the convict (Continuous Constant Allocation (CCA). To account for the redistribution of resources we extended this allocation scheme to the case in which continuous constant allocation is followed by redistribution of the resources (Continuous Constant Allocation with Redistribution (CCAR)). In each of these formulations we define the conditions for an optimal resource partitioning and allocation. We were able to obtain analytical expression for resource partitioning in almost all of these cases. Next, in order to consider situations in which area fire is required, we developed a (2,1) model using Lanchester linear law model for attrition. Here we considered a resource allocation problem in which the resource allocation is done using ideas similar to the square law case. In the Linear law, the resources will get destroyed completely only at infinite time, hence a situation for redistribution of resources does not arise for this law. We considered Time Zero Allocation and Continuous Constant Allocation schemes for this law. We obtained analytical results for the TZA scheme. For the CCA scheme, closed form solutions are difficult to obtain but numerical solutions were obtained. The above schemes were extended to an (n, 1) model for resource allocation using Lanchester square and linear laws. Here the defending forces have to determine an optimal partitioning of available resources to counter attacks from an adversary from n different fronts. For the square law model, we considered both TZA and CCA schemes for resource allocation. As the number of force types increases, the equations becomes much more complicated and the analytical solutions are difficult to obtain. We were able to obtain analytical solutions for some of the situations that occurs during the conflict. For the linear law, we considered only the TZA scheme since, even for the simpler (2,1) model, the analytical solutions are difficult to obtain for the CCA scheme. The resource allocation strategies developed in this thesis contribute to the growing research in the field of conflicts. The thesis concludes with a discussion on some future Extensions of this work.

Biodiversity can be crucial for an ecosystem to uphold its’ functions. Thus, is population declines a major threat to biodiversity. One type of species-rich habitat linked to several ecosystem services is the Swedish pasture. Albeit during the latter half of the 20th-century observations could be made of many population declines in several species of farmland birds. The population decline is directly linked to intensification of arable lands due to method modernization, conversion of pastures to fields and pesticide use. This study focused on comparing the fauna of birds in pasture lands surrounded by forest-dominated or cropland-dominated areas within a 500 m radius of a semi-natural pasture. 100plots were extracted (50 of each land use) for analysis. Data was provided by voluntarily collected stocktaking from the environmental surveillance program Svensk Fågeltaxering. A CCA was made on the species composition with amounts of forest and amounts of fields as variables. The effect on species richness from land use was calculated using GLM. The result showed no difference between bird species richness or species composition between forest-dominated pastures and cropland dominated pastures. This could indicate that birds are no longer affected by the intensification of modern arable farming or that local habitat elements like hedges and ditches are structures more critical factors for nesting farmland birds than land use within a 500 m radius surrounding pastures.

The use of mineral adition in concrete is a widely studied theme for several researchers that looking for features like: save cement for reducing costs, durability improvement to increase mechanical strenght and use of industrial wastes for reducing environmental pollution. This study intend to analize the microstructure of concretes mixtures with ungrounded residual rice husk ash addition without burn control unground (RHAN), like a partial cement substitute in conventional concrete for reducing costs, since cement is the most expensive component, and the use RHAN avoiding dumping on environment like a ground and water pollutant. Five different concrete mixtures proportions: 2 mixes of RHAN, with 15% and 25% of partial cement substitution, 2 mixes of ground RHA (RHAM), with 15% and 25% of partial cement substitution, for comparison, and a control design, withouth adition. All concrete disigns were developed for 3 water/binder relationships (0,45, 0,55 e 0,65), 15 differents concrete design in total, for ages 28 and 91 days, were done. Tests like: axial compressive strenght, percentual of chemically combined water, mercury intrusion porosimetry,X-ray difraction and image analysis by scanning eletronic microscope (SEM) combined energy dispersive spectroscopy (EDS) were done. Tests results proved that RHA use is feasible for 15% of substitution of cement by RHAN, since concretes had values of compressive strenght few smaller than control concrete values, at 28 days, however higher than it at 91 days. Because of pozolanic reaction and filler efect combination, of RHAN and RHAM particles, concrete with RHA adition had microstructural changes like: size pore refinement, total porosity reduction and calcium silicate hydrate (C-S-H) formation through pozolanic reaction. RHA Inert particles created nucleation sites improving hydrate crystals formation. / O uso de adições minerais em concretos é um tema bastante estudado por vários pesquisadores que buscam características como: redução do consumo de cimento para redução de custos, aumento da durabilidade, aumento da resistência mecânica e aproveitamento de resíduos industriais para redução da poluição ambiental. Este estudo pretende analisar a microestrutura dos concretos dosados com adição de cinza de casca de arroz residual sem controle de queima e sem moagem (CCAN), em substituição parcial de cimento em concretos convencionais com a finalidade de redução de custos, já que o cimento é o componente mais caro do concreto e também aproveitar a CCAN evitando assim que seja descartada no ambiente como um poluente de água e solo. Foram estudados diferentes traços de concreto: 2 traços com CCAN em teores de 15 e 25% de substituição parcial de cimento, 2 traços com CCA moída (CCAM) em teores de 15 e 25% de substituição parcial de cimento, para comparação, e um traço de referência, ou seja sem substituição de cimento. Cada traço foi desenvolvido para 3 relações a/ag (0,45, 0,55 e 0,65), totalizando então 15 diferentes traços, que foram estudados para as idades de 28 e 91 dias. Foram realizados ensaios de resistência à compressão axial, teor de água quimicamente combinada, porosidade por intrusão de mercúrio, difração de raios x e análise de imagens no microscópio eletrônico de varredura (MEV) combinado com a espectrometria de dispersão de raios X (EDS). Os resultados demonstraram que a utilização da CCAN é viável para teores de 15% de substituição de cimento, já que produziu concretos com valores de resistência à compressão pouco inferiores aos valores do concreto de referência, aos 28 dias, porém superiores a este quando a idade analisada é 91 dias. Devido à combinação da reação pozolânica e efeito filler das partículas de CCAN e CCAM, os concretos com adição de CCA apresentaram modificações da microestrutura como: refinamento dos poros, redução da porosidade total, formação de silicatos de cálcio hidratados (C-S-H) a partir da reação pozolânica. Partículas inertes de CCA criaram também espaços para a nucleação aumentando a formação de cristais hidratados.

Les ARNt sont des molécules adaptatrices reliant l'information génétique de l’ARN messagers à la séquence d'acides aminés primaire des protéines. Les ARNt ont une structure typique, appelée "feuille de trèfle". Certains ARNt mitochondriaux montrent une forte dérivation de cette structure. Un cas extrême peut être observé dans les mitochondries du nématode R. culicivorax. Cette étude vise la caractérisation fonctionnelle de ces ARNt «bizarres» et de définir leurs propriétés structurales et leur fonctionnalité avec des protéines partenaires telles que les CCAses et les aminoacyl-ARNt synthetases. Ce travail révèle que les ARNt sans bras forment une structure secondaire en forme d'épingle à cheveux et que leurs structures 3D présentent une grande flexibilité intrinsèque. Les tests initiaux n’ont pas démontré l'activité d'aminoacylation. Cependant, les ARNt sans bras représentent des molécules fonctionnelles pour le CCAse, indiquant des adaptations de l’enzyme aux ARNt sans bras. / TRNAs are adapter molecules linking the genetic information of messenger RNAs with the primary amino acid sequence of proteins. tRNAs have a typical cloverleaf-like secondary structure. Some mitochondrial tRNAs show a high derivation from this canonical tRNA structure. An extreme case of structural truncations can be observed in mitochondria of the nematode R. culicivorax. This study aims the functional characterization of such “bizarre” tRNAs in defining their structural properties and their functionality with interacting partner proteins such as CCA-adding enzymes and aminoacyl-tRNA synthetases. This work reveals that armless tRNAs form a hairpin-shaped secondary structure. 3D structures exhibit a high intrinsic flexibility. Initial tests could not demonstrate aminoacylation activity. However, armless tRNAs represent functional molecules for CCA-incorporation, indicating adaptations of CCA-adding enzymes to armless tRNAs.

The master's thesis deals with problems which is associated with rough detection of distance between wireless modules based on ZigBee technology. In the first logical part it theoretically describes this technology and their characteristics. This section gives basic informations needed to understand the operation of wireless communications and also acquaint him with some of the terms from this sphere. Next thing is description of the medium access together with a detailed description of functions that are crucial for deter-mining the signal strength. The second part is devoted to describe the 1321XDSK-BDM development kit. Another section is devoted to the design of the user's interface for displaying measured data. It consists of a theoretical design, which describes the initial vision of the device accompanied by solution of communication between wireless module and the proposed device. Follows the design of the involvement in Eagle software and explanation of the various components. In the last two chapters of the whole logical structure is described construction of the device and simple user's guide. The following chapter talks about the selection of suited application, necessary changes and own implementation of source code. There is even a description of important features and components of the application. The penultimate chapter contains a distance measurement in terrain using wireless modules and designed device. Here are tested different influences on the final distance measurement accuracy. In conclusion there is a debate over the results achieved. Particular, this section includes an assessment of precision measuring methods and evaluates aplicability of this method in practice.